Background: Off-pump coronary artery bypass grafting (OPCAB) is considered a safer alternative to on-pump surgery, especially in patients with left ventricular dysfunction (LVD). Objectives: This study assessed short-...Background: Off-pump coronary artery bypass grafting (OPCAB) is considered a safer alternative to on-pump surgery, especially in patients with left ventricular dysfunction (LVD). Objectives: This study assessed short-term outcomes and functional improvements in LVD patients post-OPCAB. Methods: The study included 200 coronary artery disease patients who underwent isolated off-pump coronary artery bypass grafting (OPCAB) at the National Heart Foundation Hospital and Research Institute between January 2019 and June 2020. Patients were categorized into Group 1, with a left ventricular ejection fraction (LVEF) of 30% - 39%, and Group 2, with an LVEF of 40% or higher. Echocardiographic assessments of left ventricular dimensions and ejection fraction were performed preoperatively, at discharge, and one month postoperatively. Results: In Group 1, preoperative left ventricular internal dimensions during diastole (LVIDd) and systole (LVIDs) were 53.48 ± 4.40 mm and 44.23 ± 3.93 mm, respectively, with a left ventricular ejection fraction (LVEF) of 35.28% ± 2.26%. At discharge, these values improved to 51.58 ± 4.04 mm (LVIDd), 41.23 ± 5.30 mm (LVIDs), and 39.25% ± 3.75% (LVEF). One month postoperatively, further improvements were observed: 46.29 ± 3.76 mm (LVIDd), 37.45 ± 3.68 mm (LVIDs), and 43.22% ± 4.67% (LVEF). Group 2 showed similar positive outcomes, with preoperative values of 47.09 ± 5.06 mm (LVIDd), 35.11 ± 5.25 mm (LVIDs), and 50.13% ± 7.25% (LVEF), improving to 42.37 ± 4.18 mm (LVIDd), 31.05 ± 4.19 mm (LVIDs), and 55.33% ± 7.05% (LVEF) at one month postoperatively. Both groups demonstrated significant improvements in left ventricular function and NYHA class, with most patients moving from class III/IV to I/II. Complications were minimal, and no mortality was observed. Conclusion: OPCAB is safe and effective for patients with LVEF 30% - 39% and LVEF ≥ 40%, providing significant short-term functional improvements without increased risk.展开更多
From emerging pollutants to emerged threat,researchers are continuously looking for promising technologies for wastewater treatment.Adsorption has been identified as the most convenient approach for treating wastewate...From emerging pollutants to emerged threat,researchers are continuously looking for promising technologies for wastewater treatment.Adsorption has been identified as the most convenient approach for treating wastewater at low-cost and with high-efficiency.Recently,graphene and its derivatives have gained heightened attention as novel adsorbents because of their unique molecular structure and outstanding physicochemical properties.Heavy metals,dyes,polycyclic aromatic hydrocarbons(PAHs)and other pollutants,which are widely concerned recently,all show different adsorption behaviors.Numerous functional groups,resonating and delocalizedπ-electron system of graphene derivatives lead to the formation of various adsorptive interactions i.e.,π-πinteractions,electrostatic interactions,Hbonding,etc.with these venomous pollutants,and quarantine them in solution.The pristine form of graphene subsidiaries tends to exhibit low sorption efficiency due to high propensity of agglomeration,lack of selectivity,hydrophobicity and difficulty in phase separation a fter treatment.Therefore,designing of efficient graphene composites through the surface modification with numerous functional groups,polymers or nanoparticles is an ongoing challenge.Complex graphene composites are increasingly reported,but the fate of pollutants and adsorption mechanisms are still far to be fully clarified.This review summarizes the recent progresses in the application of graphene-based adsorbents for eliminating a wide range of organic and inorganic pollutants from wastewater.A critical explanation is provided on the synthesis of graphene adsorbents,systematic adsorption and desorption mechanisms along with their pollutant removal performances under different experimental conditions.A brief perspective on upcoming research needs and challenges involved in the designing of high-quality graphene-based adsorbents are highlighted.展开更多
Water electrolysis is considered as the most capable and old technology for <span style="font-family:Verdana;">hydrogen fuel preparation. Electrolysis needs external electrical energy through </span...Water electrolysis is considered as the most capable and old technology for <span style="font-family:Verdana;">hydrogen fuel preparation. Electrolysis needs external electrical energy through </span><span style="font-family:Verdana;">electrodes to split water into hydrogen and oxygen. An efficient electrolysis requires suitable electrodes to minimize potential drop. In this study Aluminium and Copper Coated Aluminium were used as different combination of Anodes and Cathodes to find out more efficient electrodes combination. NaCl solution in rain water was taken as electrolyte. Rain water was taken to avoid ionic impedance of tap water and expenses of distilled water. In this study, the most efficient electrode combination was Copper Coated Aluminium (anode)</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Aluminium (cathode) and gave the highest efficiency of hydrogen production to about 11% at normal temperature for very low concentration of NaCl (0.051</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">M) which increased with temperature, up to 29% upon rising of temp to 60<span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">°</span></span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">C. It was showed that higher concentration of electrolyte would surge the efficiency significantly. If the supplied heat could be provided from any waste heat sources then this study would be more efficient. However, current research evaluated the technical feasibility of this electrode combination for producing hydrogen with electrolysis of rain water utilizing electricity and modified electrodes.</span></span><展开更多
Development of generic drug product by pharmaceutical industry is a scientific and technical approach which is totally different from developing a reference or innovator product. Most of the developing countries focus...Development of generic drug product by pharmaceutical industry is a scientific and technical approach which is totally different from developing a reference or innovator product. Most of the developing countries focus on developing the generic drug products because huge amount of investment is required for innovation and to develop reference product. The generic medicine has to be bioequivalent to the innovator drug and ensure the same biological effect with proper safety and efficacy. Nowadays, the pharmaceutical industries focus on the development of generic product as this does not require that much time and cost compared to the innovator company. But development of generic product is also difficult as it contains the same therapeutic efficacy as innovator. The development approach is based on the target market, i.e. US market, EU market. If a manufacturer targets the US market, then all excipients should be USP grade, analysis should be conducted by USP method or in-house method and stability studies as well. Prior and during the development of generic drug product API selection, dosage form selection, reference product selection and characterization, formulation development, analytical method development, tech transfer or submission batch are prime concern. Then again, bioequivalence study, drug registration procedure and commercialization of the generic product considering regulatory guidance of respective regulatory agencies and the approaches taken by the regulatory agencies for the development of registration of generic medicines are also crucial as well for the development of generic drug product. The aim of this study was to review the entire stage of a generic drug development by a generic pharmaceutical company.展开更多
<span style="font-family:Verdana;">The current study evaluated the antioxidant, </span><i><span style="font-family:Verdana;">α</span></i><span style="fo...<span style="font-family:Verdana;">The current study evaluated the antioxidant, </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-amylase inhibitory and anti-</span><i><span style="font-family:Verdana;">Staphylococcus</span></i> <i><span style="font-family:Verdana;">aureus</span></i><span style="font-family:Verdana;"> activities of the fruiting bodies of </span><i><span style="font-family:Verdana;">Ganoderma</span></i> <i><span style="font-family:Verdana;">lucidum</span></i><span style="font-family:Verdana;">. Methanolic extract of </span><i><span style="font-family:Verdana;">G.</span></i> <i><span style="font-family:Verdana;">lucidum</span></i><span style="font-family:Verdana;"> (MEGL) was investigated for its </span><i><span style="font-family:Verdana;">in</span></i> <i><span style="font-family:Verdana;">vitro</span></i><span style="font-family:Verdana;"> antioxidant activity using 1,1-diphenyl 2-picrylhydrazyl (DPPH) assay and EC</span><sub><span style="font-family:Verdana;">50</span></sub><span style="font-family:Verdana;"> value was determined. </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-Amylase inhibitory and anti-</span><i><span style="font-family:Verdana;">S.</span></i> <i><span style="font-family:Verdana;">aureus</span></i><span style="font-family:Verdana;"> activities were carried out by conventional methods. The mushroom extract showed maximum free radical scavenging activity at a dose of 500 μg/mL with EC</span><sub><span style="font-family:Verdana;">50</span></sub><span style="font-family:Verdana;"> value of 22.1399 μg/mL. EC</span><sub><span style="font-family:Verdana;">50</span></sub><span style="font-family:Verdana;"> value for the inhibition of </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-amylase activity was found 22.6011 μg/mL. </span><i><span style="font-family:Verdana;">G.</span></i> <i><span style="font-family:Verdana;">lucidum</span></i><span styl展开更多
Polycrystalline xBa<sub>0.95</sub>Sr<sub>0.05</sub>TiO<sub>3</sub>-(1 - x)BiFe<sub>0.90</sub>Gd<sub>0.10</sub>O<sub>3</sub> ceramics were prepare...Polycrystalline xBa<sub>0.95</sub>Sr<sub>0.05</sub>TiO<sub>3</sub>-(1 - x)BiFe<sub>0.90</sub>Gd<sub>0.10</sub>O<sub>3</sub> ceramics were prepared by standard solid state reaction technique using the solid solution of BaCO<sub>3</sub>, SrCO<sub>3</sub>, TiO<sub>2</sub>, Bi<sub>2</sub>O<sub>3</sub>, Fe<sub>2</sub>O<sub>3</sub> and Gd<sub>2</sub>O<sub>3</sub>. The compound is a BiFeO<sub>3</sub> based multiferroic material which contains both magnetic and electric properties. The synthesized ceramics noticed better properties than xBaTiO<sub>3</sub>-(1 - x)BiFeO<sub>3</sub> because of adding rare earth element Gd which have higher magnetic moment than Fe. The prepared samples were sintered at 900<span style="font-size:12px;white-space:nowrap;"><span style="font-size:12px;white-space:nowrap;">˚</span></span>C, 950<span style="font-size:12px;white-space:nowrap;"><span style="font-size:12px;white-space:nowrap;">˚</span></span>C and 1000<span style="font-size:12px;white-space:nowrap;"><span style="font-size:12px;white-space:nowrap;">˚</span></span>C for 1 h. The effect of sintering temperature on density of the compound, complex initial permeability, dielectric properties and complex impedance analysis was reported in this article. Density of the ceramics was found to be enhanced with the rise in sintering temperature which implied porosity of the compound decreased when sintering temperature was increased. Enhanced complex initial permeability was noticed for the samples up to 950<span style="font-size:12px;white-space:nowrap;"><span style="font-size:12px;white-space:nowrap;">˚</span></span>C and this might be attributed to reducing the motion of domain wall when the ceramics were sintered above 950<span style="font-size:12px;white-space:nowrap;"><span style="font-size:12px;white-space:nowrap;">˚</span></span>C. Value of dielectric constant increased whereas dielectric loss decreased and these modifications might be expected because of changing density and grain size due to the variation of si展开更多
Mangrove soils are well known for their high capacity of storing organic carbon (SOC) in various pools;however, a relatively small change in SOC pools could cause significant impacts on greenhouse gas concentrations. ...Mangrove soils are well known for their high capacity of storing organic carbon (SOC) in various pools;however, a relatively small change in SOC pools could cause significant impacts on greenhouse gas concentrations. Thus, for an in-depth understanding of SOC distribution and stock to predict the role of Sundarbans mangrove in mitigating global warming and greenhouse effects, different extraction methods were employed to fractionate the SOC of Sundarbans soils into cold-water (CWSC) and hot-water (HWSC) soluble, moderately labile (MLF), microbial biomass carbon (MBC), and resistant fractions (RF) using a newly developed modified-method. A significant variation in total SOC (p < 0.001), SOC stock (p < 0.001) and soil bulk density (p < 0.05) at the Sundarbans mangrove forest were observed. In most soils, bulk density increased from the surface to 100 cm depth. The total SOC concentrations were higher in most surface soils and ranged from 1.21% ± 0.02% to 8.19% ± 0.09%. However, C in lower layers may be more resistant than that of upper soils because of differences in compositions, sources and environmental conditions. SOC was predominately associated with the resistant fraction (81% - 97%), followed by MLF (2% - 10%), HWSC (1% - 4%), MBC (~0% - 4%), and CWSC (~0% - 3%). The significant positive correlations between different C fractions suggested that C pools are interdependent and need proper management plans to increase these pools in Sundarbans soils. The SOC stock of the studied areas ranged between 16.75 ± 3.83 to 135.12 ± 28.61 kg·C·m<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>2</sup> in 1 m soil profile and has an average of 31.80 kg·C·m<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>2</sup>. The substratum soils had more carbon than the upper layers in the Sundarbans wetland due to burial and preservation of carbon by frequent tidal inundation. A higher SOC stock in the soil profile and its primary associ展开更多
Zinc Sulfide (ZnS) thin film has attracted increasing attention due to their potential applications in the new generation of nano-electronics and opto-electronics devices. The physical and chemical properties of ZnS h...Zinc Sulfide (ZnS) thin film has attracted increasing attention due to their potential applications in the new generation of nano-electronics and opto-electronics devices. The physical and chemical properties of ZnS have outstanding quality for different applications. Moreover, ZnS doped with various elements are creating a new era for both academic research and industrial applications. So, the optical properties of modified ZnS thin film will help us to find a suitable doping element for convenient deposition which may enhance the conductance and transmitting properties of the film. This review work has been carried out to explore the four-modification elements that constitute Cu, Ni, Co & Fe as descending order of atomic number corresponding to Zn, along with some potential applications considering the recent research work with other doping elements too such as Al, C, Pt etc. For example, FE, FET, Catalytic, Solar cell, Electroluminescence, Fuel cell, different sensors (Chemical sensors, Bio-sensors, Humidity sensors, light sensors, UV light sensors) and nanogenerators use ZnS thin film.展开更多
The literature gap in microfinance paradox of double bottom line(financial performance vs.outreach)has always been an interesting area of research.This paper proposes a theoretical model most suitable for Islamic Micr...The literature gap in microfinance paradox of double bottom line(financial performance vs.outreach)has always been an interesting area of research.This paper proposes a theoretical model most suitable for Islamic Microfinance Institutions(MFIs)which enables Islamic MFIs’to operate together with the existing financial models compliant with Islamic Shariah Law.This model is based on a distributed verification/decision-making process that might be realized(but not necessary)through block-chain.Among the available distributed verification techniques,blockchain technology is an attractive emerging computing paradigm due to its decentralized,immutable,shared,and secure data structure characteristics.This model proposes three significant propositions.First,sharing information through blockchain will allow a transparent network in MFI operations,which will raise confidence for donors resulting in a causal effect of a relatively lower profit rate to be charged by the MFIs.Second,the consensus mechanism will enable risk-sharing,a character of Islamic finance;thus,the MFIs will operate without any collateral for low-risk firms.Third,the double bottom line of MFIs’long-lasting paradox would be solved.As for practical implication of this proposed model,the causal impact of lower cost investment by the lenders would increase social welfare because of no collateral and no initial wealth requirement.The proposed model proposes a credit rationing approach where profit can be negative.No collateral will be used when calculating the creditworthiness of a borrower.展开更多
The impact of Cr3+ ion on the magnetic properties of Mn0.50Zn0.50CrxFe2-xO4 (with x = 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5) has been studied. Ferrite samples were synthesized by combustion method and sintered at various te...The impact of Cr3+ ion on the magnetic properties of Mn0.50Zn0.50CrxFe2-xO4 (with x = 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5) has been studied. Ferrite samples were synthesized by combustion method and sintered at various temperatures (1250°C, 1300°C and 1350°C). The structural properties were investigated by means of X-ray diffraction patterns and indicated that the samples possess single phase cubic spinel structure. The lattice parameter decreases with the increase in Cr3+ content, as the ionic radius of Cr3+ ion is smaller than that of Fe3+. The average grain size (D), bulk density (ρB) and initial permeability (μi’ )decreases with increase in Cr3+ content whereas porosity follows its opposite trend. The ρB was found to increase with increase in Cr3+ content as the sintering temperature (Ts) is increased from 1250°C to 1350°C. The Ts affects the densification, grain growth and (μi’ ) of the samples. The (μi’ ) strongly depends on average grain size, density and intragranular porosity. The B-H loops of the compositions were measured at room temperature. The saturation magnetization (Ms), coercivity (Hc) and hysteresis losses were studied as a function of Cr3+ content. The Ms was found to decrease with the increase of Cr3+ content, which is attributed to the dilution of A-B interaction.展开更多
Since anemia is one of the most skyrocketed public health problems worldwide, an investigation has thus been conducted to assess the prevalence and associated factors of anemia among the pregnant women receiving anten...Since anemia is one of the most skyrocketed public health problems worldwide, an investigation has thus been conducted to assess the prevalence and associated factors of anemia among the pregnant women receiving antenatal care (ANC) at Fatima Hospital in Jashore, Bangladesh. Facility-based cross-sectional study was carried out among 384 pregnant women at Fatima hospital, Bangladesh from February to April, 2019. Data were obtained using a structured questionnaire and participant’s current medical record card. Binary logistic regression analysis was used to identify factors associated with anemia and a P-value < 0.05 was considered as statistically significance. The overall prevalence of anemia among pregnant women was 58.9% (226/384). Out of 226 anemic pregnant mothers, 36.3% (82/226) were mildly anemic, 62.4% (141/226) were moderately anemic and 1.3% (3/384) was severely anemic. Binary logistic regression analysis revealed that the following variables were significantly associated with anemia: Monthly family income (11,000 - 20,000 Taka) [AOR (95% CI) = 0.45 (0.21 - 0.98)], Family size (joint) [AOR (95% CI) = 1.59 (1.03 - 2.45)], Gestational age (third trimester) [AOR (95% CI) = 2.18 (1.40 - 3.40)], birth spacing < 2 years [AOR (95% CI) = 2.87 (1.51 - 5.44)], Excessive blood loss during previous surgery (Yes) [AOR (95% CI) = 2.08 (1.14 - 4.17)], Food group eaten 24 hours (1 - 4 groups) [AOR (95% CI) = 3.43 (1.84 - 6.39)], Breakfast regularly (No) [AOR (95% CI) = 3.64 (1.36 - 9.75)]. The results obtained showed that the prevalence of anemia among pregnant women is severe at Fatima Hospital in Jashore, Bangladesh.展开更多
Characterization of carbonaceous species from the particulate matters (PM) after combustion of seven commonly used biomass species, albizia tree (Albizia julibrissin), dry leaves (mahogany tree), jackfruit tree (Artoc...Characterization of carbonaceous species from the particulate matters (PM) after combustion of seven commonly used biomass species, albizia tree (Albizia julibrissin), dry leaves (mahogany tree), jackfruit tree (Artocarpus heterophyllus), rain tree (Samanea saman), mahogany tree (Swietenia mahogany), cow dung and mango tree (Mangifer aindica) was done. PM samples were collected on quartz fiber filters emitted from biomass burning in a typical rural cooking stove. PM loaded filters were characterized with scanning electron microscope (SEM) for surface morphology, fourier transform infrared (FTIR) to determine the functional group of organic compounds. Black carbon (BC) and brown carbon (BrC) concentrations were determined with Aethalometer. A TOC analyzer was used to determine the total organic carbon (TOC) present in the biomass samples. The surface morphology was almost similar for all biomass burning PM samples. The average concentrations of BC and BrC were 5.85 ± 4.40 and 13.0 ± 8.80 μg·mDž, respectively. The emission factors of BC and BrC were 1.08 ± 0.89 and 2.35 ± 1.67 mg·gǃ, respectively. Concentration of BC was the highest in dry leaves and the lowest in mango tree. The emission factors of the determined biomass followed the sequence-dry leaves of mahogany > albizia tree > jackfruit tree > rain tree > cow dung > mahogany tree > mango tree. PM from mango tree had lower emissions compared to the other biomass species used in this study.展开更多
Y-type hexagonal ferrites with the nominal chemical composition Ba2Ni2-xZnxFe12O22 (0.0 ≤ x ≤ 0.6 with a step of 0.1) have been synthesized by the conventional solid state reaction method and sintered in the tempera...Y-type hexagonal ferrites with the nominal chemical composition Ba2Ni2-xZnxFe12O22 (0.0 ≤ x ≤ 0.6 with a step of 0.1) have been synthesized by the conventional solid state reaction method and sintered in the temperature range 1150℃-1250℃ to study their structural and magnetic properties. The aim of the present work is to increase the magnetic properties of Y-type hexaferrites by Zn substitution. X-ray diffraction analysis confirms the formation of the hexagonal phase. The effect of chemical composition on the lattice parameter, density and porosity is studied. The lattice parameter increases with Zn substitution. The density increases with Zn substitution up to a certain level and after that density decreases. The ac magnetic properties of the hexaferrites sintered at temperature 1200℃ are characterized within the frequency range 100 kHz -120 MHz. The real part (μi') of the complex initial permeability for different compositions indicates that μi' decreases with increase in frequency. The permeability increases with the increase in Zn content, reaches a maximum value and then decreases with further increase in Zn content. Magnetization has been measured using the Superconducting Quantum Interference Device (SQUID) magnetometer. The saturation magnetization is observed to be maximum at x = 0.1 and then decreases with Zn content for x > 0.1. From the M-H curve it is clear that at room temperature the polycrystalline Ba2Ni2-xZnxFe12O22 compositions are in ferrimagnetic state.展开更多
Objective C/eome rutidosperma （Capparidaceae）, commonly known as ＂Fringed Spider Flower＂, is a medicinal plant found in Southeast Asia. C. rutidosperma is used in folk medicine for diuretic, laxative, analgesic, a...Objective C/eome rutidosperma （Capparidaceae）, commonly known as ＂Fringed Spider Flower＂, is a medicinal plant found in Southeast Asia. C. rutidosperma is used in folk medicine for diuretic, laxative, analgesic, anti-inflammatory, antipyretic, antimicrobial, anti-oxidant, hypoglycemic, and anthelmintic activities. We have evaluated the anti-nociceptive properties of methanol extract from C. rutidosperma （MECR） in vivo. Methods Thermal method （hot plate test and tail flick test） was induced to judge the anti-inflammatory effect and couple of chemical method also used （formalin induced licking test; writhing test carried by acetic acid） to evaluate analgesic effect. Both of these tests were made over animal models, like mice and rats. Two different doses （1 O0 and 200 mg/kg） were used for each case of test, while morphine sulphate （5mg/kg, ip） was used as reference drug. Results MECR demonstrated the significantly anti-nociceptive activity in the analgesic and anti-inflammatory tests by reducing nociception in mice models （P 〈 0.001）. in the hot-plate and tail-flick tests, MECR significantly elongated the time to response to the thermal stimuli （100 and 200 mg/kg with P 〈 0.05, 0.001）. The remarkable increase in the latency was observed at 90 and 120 min. In acetic acid-induced writhing test and formalin induced licking test for anti-inflammatory activity, MECR at 100 and 200 mg/kg doses exhibited significant （P〈 0.001） reduction of writhing and licking response. Conclusion The anti-inflammatory and analgesic effects of C. rutidosperma propose that this effect may be a result of both peripheral and central mechanisms. Further study is required to ensure the proper mechanism of action as well as the active ingredient.展开更多
Mn0.50-xZn0.50CuxFe2O4 (where x = 0.0 - 0.3) ferrites have been synthesized by auto combustion method. X-ray diffraction patterns reveal that all compositions are of single phase cubic spinel structure. The lattice pa...Mn0.50-xZn0.50CuxFe2O4 (where x = 0.0 - 0.3) ferrites have been synthesized by auto combustion method. X-ray diffraction patterns reveal that all compositions are of single phase cubic spinel structure. The lattice parameter decreases with the increase in Cu2+ content obeying the Vegard’s law. The bulk density, average grain size, initial permeability, Néel temperature and saturation magnetic induction of Mn0.50-xZn0.50CuxFe2O4 increased with increasing Cu2+content. It is observed that both density and initial permeability increase with increasing sintering temperature. The maximum initial permeability is found to be 1061 which is almost four times greater than that of the parent composition. The resonance frequency of all the samples shifts towards the lower frequency as the permeability increases with Cu2+ content. It is observed from B-H loops of Mn0.50-xZn0.50CuxFe2O4 that coercivity decreases and retentivity increases with Cu2+ content. Possible explanations for the observed magnetic properties with various Cu2+ contents are discussed.展开更多
This study investigated distribution of HLA alleles (HLADRB1*01, *03, *04, *07, HLA-DQB1*0201, *0301/4) in 34 healthy controls and 57 rheumatoid arthritis (RA) patients in a Bangladeshi population and correlated the g...This study investigated distribution of HLA alleles (HLADRB1*01, *03, *04, *07, HLA-DQB1*0201, *0301/4) in 34 healthy controls and 57 rheumatoid arthritis (RA) patients in a Bangladeshi population and correlated the genotypic frequencies with clinical parameters. Frequency distribution of HLA-DRB1*04 (34%) and HLA-DRB1*01 (32%) were the highest followed by HLA-DQB1*0301/4 (29%) and HLA-DQB1*0201 (26%) in RA patients while HLA-DRB1*03 (12%) had lowest frequency. Plasma level of anti-CCP and rheumatoid factor antibodies confirmed diagnosis of RA patients that varied significantly between patients and healthy controls. Likewise, plasma levels of C-reactive protein, triglycerides, cholesterol, HDL-cholesterol and activities of AST and ALT exhibited significant variation between the two groups. In contrast, the levels of glucose, total protein, uric acid, LDL-cholesterol and plasma activity of ALP in RA patients had no significant deviations from healthy controls. Relationship between HLA genotype frequency and clinical parameters revealed that the mean levels of anti-CCP and rheumatoid factor antibodies were highest in the patients harboring HLA-DRB1*04 allele. These findings underpin the correlation between HLA genotype with clinical markers of RA which are indicative of disease severity. The positive correlation of these markers with certain HLA genes may be used to identify susceptible individuals who are likely to have RA in Bangladeshi population.展开更多
Structural and various electrical properties of polycrystalline Ca0.5＋xNd0,5-x（Ti0.5Fe0.5）O3, prepared by standard solid state reaction technique, were studied. Formation of single phase orthorhombic structure of t...Structural and various electrical properties of polycrystalline Ca0.5＋xNd0,5-x（Ti0.5Fe0.5）O3, prepared by standard solid state reaction technique, were studied. Formation of single phase orthorhombic structure of the compositions was confirmed by X-ray diffraction study. The composition dependence of lattice parameters, density and microstructural study show that they vary significantly with Ca content. The dielectric measurements were carried out at room temperature as function of frequency and composition. The experimental results reveal that the dielectric constant （ε′） increases with increasing Ca content. Similar behavior is observed for the dielectric loss （tanδ） and ac conductivity （σac）. In complex impedance analysis it is observed that the real part （Z′） vs imaginary part （Z″） graph exhibits a tendency of formation of a single semicircular arc for each composition of samples. Different parameters were determined by fitting the experimental data in Cole-Cole empirical formula. A dominance of grain boundary resistance （Rgb） is observed. The Rgb decreases with increasing Ca content. The high ε′ observed in present samples are suitable for fabrication of devices.展开更多
The electrical properties of Ni_(0.27)Cu_(0.10)Zn_(0.63)Fe_(2)O_(4)(NCZF)prepared from auto combustion synthesis of ferrite powders have been studied by impedance and modulus spectroscopy.We studied frequency and temp...The electrical properties of Ni_(0.27)Cu_(0.10)Zn_(0.63)Fe_(2)O_(4)(NCZF)prepared from auto combustion synthesis of ferrite powders have been studied by impedance and modulus spectroscopy.We studied frequency and temperature dependencies of impedance and electric modulus of NCZF in a wide frequency range(20 Hz-5 MHz)at different measuring temperatures T_(SM)(30-225℃).The complex impedance spectra clearly showed both grain and grain boundary effects on the electrical properties.The observed impedance spectra indicated that the magnitude of grain boundary resistance R_(gb) becomes more prominent compared to grain resistance R_(b) at room temperature,and with the increase in T_(SM),R_(gb) decreases faster than the intrinsic R_(b).The frequency response of the imaginary part of impedance showed relaxation behavior at every T_(SM),and the relaxation frequency variation with T_(SM) appeared to be of Arrhenius nature and the activation energy has been estimated to be 0.37 eV.A complex modulus spectrum was used to understand the mechanism of the electrical transport process,which indicated that a non-Debye type of conductivity relaxation characterizes this material.展开更多
xBa_（0.95）Sr_（0.05）TiO_3–（1-x）BiFe_（0.9）Gd_（0.1）O_3[x BST–（1-x）BFGO]（x = 0.00, 0.10, 0.20 and 0.25） multiferroic ceramics were prepared by the standard solid-state reaction technique. Structural charac...xBa_（0.95）Sr_（0.05）TiO_3–（1-x）BiFe_（0.9）Gd_（0.1）O_3[x BST–（1-x）BFGO]（x = 0.00, 0.10, 0.20 and 0.25） multiferroic ceramics were prepared by the standard solid-state reaction technique. Structural characterization was performed by X-ray diffraction. All the samples showed rhombohedral distorted perovskite structure. Surface morphology of the ceramics was studied by the field emission scanning electron microscope（FESEM）. From the FESEM observation, the grain size was observed to be decreased with increasing BST content. Enhanced magnetic properties were observed in BFGO with the increase in BST content because of large lattice distortion. The complex initial permeability increased with the increasing of BST content. The study of dielectric properties showed that the dielectric constant increased, whereas dielectric loss decreased with increasing of BST content due to the reduction of oxygen vacancies. An analysis of the electric impedance and modulus with frequency was performed at different temperatures. Non-Debye-type relaxation processes occur in the compound which was confirmed from the nature of the Cole–Cole plot. The DC conductivity was found to increase with the rise in temperature which indicates the semiconducting behavior of the compound with characteristics of the negative temperature coefficient of resistance. The activation energy, responsible for the relaxation determined from the modulus spectra（0.246 eV）, was found to be almost same as the value obtained from the impedance study（0.240 eV）, indicating that charge carriers overcome the same energy barrier during relaxation. The frequency response of imaginary parts of electric impedance and modulus suggested that the relaxation in xB ST–（1-x）BFGO ceramics follows the same mechanism at various temperatures.展开更多
Various polycrystalline Ba1-x Lax (Ti0.5 Fe0.5 )O3 are prepared by using the standard solid state reaction technique.Pellet shaped samples prepared from each composition are sintered at 1200℃ for 5 h.X-ray diffractio...Various polycrystalline Ba1-x Lax (Ti0.5 Fe0.5 )O3 are prepared by using the standard solid state reaction technique.Pellet shaped samples prepared from each composition are sintered at 1200℃ for 5 h.X-ray diffraction patterns of these compositions confirm the formation of a single phase perovskite structure.The lattice parameters are decreased but the average grain size increases with the increase of La content.The dielectric constant,dielectric loss and ac conductivity are studied as a function of frequency for various compositions,and their behaviors are explained on the basis of the Maxwell-Wagner model A three-times enhancement of the dielectric constant is observed with the increase of La content.展开更多
文摘Background: Off-pump coronary artery bypass grafting (OPCAB) is considered a safer alternative to on-pump surgery, especially in patients with left ventricular dysfunction (LVD). Objectives: This study assessed short-term outcomes and functional improvements in LVD patients post-OPCAB. Methods: The study included 200 coronary artery disease patients who underwent isolated off-pump coronary artery bypass grafting (OPCAB) at the National Heart Foundation Hospital and Research Institute between January 2019 and June 2020. Patients were categorized into Group 1, with a left ventricular ejection fraction (LVEF) of 30% - 39%, and Group 2, with an LVEF of 40% or higher. Echocardiographic assessments of left ventricular dimensions and ejection fraction were performed preoperatively, at discharge, and one month postoperatively. Results: In Group 1, preoperative left ventricular internal dimensions during diastole (LVIDd) and systole (LVIDs) were 53.48 ± 4.40 mm and 44.23 ± 3.93 mm, respectively, with a left ventricular ejection fraction (LVEF) of 35.28% ± 2.26%. At discharge, these values improved to 51.58 ± 4.04 mm (LVIDd), 41.23 ± 5.30 mm (LVIDs), and 39.25% ± 3.75% (LVEF). One month postoperatively, further improvements were observed: 46.29 ± 3.76 mm (LVIDd), 37.45 ± 3.68 mm (LVIDs), and 43.22% ± 4.67% (LVEF). Group 2 showed similar positive outcomes, with preoperative values of 47.09 ± 5.06 mm (LVIDd), 35.11 ± 5.25 mm (LVIDs), and 50.13% ± 7.25% (LVEF), improving to 42.37 ± 4.18 mm (LVIDd), 31.05 ± 4.19 mm (LVIDs), and 55.33% ± 7.05% (LVEF) at one month postoperatively. Both groups demonstrated significant improvements in left ventricular function and NYHA class, with most patients moving from class III/IV to I/II. Complications were minimal, and no mortality was observed. Conclusion: OPCAB is safe and effective for patients with LVEF 30% - 39% and LVEF ≥ 40%, providing significant short-term functional improvements without increased risk.
基金the National Natural Science Foundation of China(No.51778230)National Key Research and Development Program(No.2017YFB06026)+1 种基金Shanghai Rising-Star Program(No.17QA1401000)the Fundamental Research Funds for the Central Universities for their financial support(No.222201718003)。
文摘From emerging pollutants to emerged threat,researchers are continuously looking for promising technologies for wastewater treatment.Adsorption has been identified as the most convenient approach for treating wastewater at low-cost and with high-efficiency.Recently,graphene and its derivatives have gained heightened attention as novel adsorbents because of their unique molecular structure and outstanding physicochemical properties.Heavy metals,dyes,polycyclic aromatic hydrocarbons(PAHs)and other pollutants,which are widely concerned recently,all show different adsorption behaviors.Numerous functional groups,resonating and delocalizedπ-electron system of graphene derivatives lead to the formation of various adsorptive interactions i.e.,π-πinteractions,electrostatic interactions,Hbonding,etc.with these venomous pollutants,and quarantine them in solution.The pristine form of graphene subsidiaries tends to exhibit low sorption efficiency due to high propensity of agglomeration,lack of selectivity,hydrophobicity and difficulty in phase separation a fter treatment.Therefore,designing of efficient graphene composites through the surface modification with numerous functional groups,polymers or nanoparticles is an ongoing challenge.Complex graphene composites are increasingly reported,but the fate of pollutants and adsorption mechanisms are still far to be fully clarified.This review summarizes the recent progresses in the application of graphene-based adsorbents for eliminating a wide range of organic and inorganic pollutants from wastewater.A critical explanation is provided on the synthesis of graphene adsorbents,systematic adsorption and desorption mechanisms along with their pollutant removal performances under different experimental conditions.A brief perspective on upcoming research needs and challenges involved in the designing of high-quality graphene-based adsorbents are highlighted.
文摘Water electrolysis is considered as the most capable and old technology for <span style="font-family:Verdana;">hydrogen fuel preparation. Electrolysis needs external electrical energy through </span><span style="font-family:Verdana;">electrodes to split water into hydrogen and oxygen. An efficient electrolysis requires suitable electrodes to minimize potential drop. In this study Aluminium and Copper Coated Aluminium were used as different combination of Anodes and Cathodes to find out more efficient electrodes combination. NaCl solution in rain water was taken as electrolyte. Rain water was taken to avoid ionic impedance of tap water and expenses of distilled water. In this study, the most efficient electrode combination was Copper Coated Aluminium (anode)</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Aluminium (cathode) and gave the highest efficiency of hydrogen production to about 11% at normal temperature for very low concentration of NaCl (0.051</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">M) which increased with temperature, up to 29% upon rising of temp to 60<span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">°</span></span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">C. It was showed that higher concentration of electrolyte would surge the efficiency significantly. If the supplied heat could be provided from any waste heat sources then this study would be more efficient. However, current research evaluated the technical feasibility of this electrode combination for producing hydrogen with electrolysis of rain water utilizing electricity and modified electrodes.</span></span><
文摘Development of generic drug product by pharmaceutical industry is a scientific and technical approach which is totally different from developing a reference or innovator product. Most of the developing countries focus on developing the generic drug products because huge amount of investment is required for innovation and to develop reference product. The generic medicine has to be bioequivalent to the innovator drug and ensure the same biological effect with proper safety and efficacy. Nowadays, the pharmaceutical industries focus on the development of generic product as this does not require that much time and cost compared to the innovator company. But development of generic product is also difficult as it contains the same therapeutic efficacy as innovator. The development approach is based on the target market, i.e. US market, EU market. If a manufacturer targets the US market, then all excipients should be USP grade, analysis should be conducted by USP method or in-house method and stability studies as well. Prior and during the development of generic drug product API selection, dosage form selection, reference product selection and characterization, formulation development, analytical method development, tech transfer or submission batch are prime concern. Then again, bioequivalence study, drug registration procedure and commercialization of the generic product considering regulatory guidance of respective regulatory agencies and the approaches taken by the regulatory agencies for the development of registration of generic medicines are also crucial as well for the development of generic drug product. The aim of this study was to review the entire stage of a generic drug development by a generic pharmaceutical company.
文摘<span style="font-family:Verdana;">The current study evaluated the antioxidant, </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-amylase inhibitory and anti-</span><i><span style="font-family:Verdana;">Staphylococcus</span></i> <i><span style="font-family:Verdana;">aureus</span></i><span style="font-family:Verdana;"> activities of the fruiting bodies of </span><i><span style="font-family:Verdana;">Ganoderma</span></i> <i><span style="font-family:Verdana;">lucidum</span></i><span style="font-family:Verdana;">. Methanolic extract of </span><i><span style="font-family:Verdana;">G.</span></i> <i><span style="font-family:Verdana;">lucidum</span></i><span style="font-family:Verdana;"> (MEGL) was investigated for its </span><i><span style="font-family:Verdana;">in</span></i> <i><span style="font-family:Verdana;">vitro</span></i><span style="font-family:Verdana;"> antioxidant activity using 1,1-diphenyl 2-picrylhydrazyl (DPPH) assay and EC</span><sub><span style="font-family:Verdana;">50</span></sub><span style="font-family:Verdana;"> value was determined. </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-Amylase inhibitory and anti-</span><i><span style="font-family:Verdana;">S.</span></i> <i><span style="font-family:Verdana;">aureus</span></i><span style="font-family:Verdana;"> activities were carried out by conventional methods. The mushroom extract showed maximum free radical scavenging activity at a dose of 500 μg/mL with EC</span><sub><span style="font-family:Verdana;">50</span></sub><span style="font-family:Verdana;"> value of 22.1399 μg/mL. EC</span><sub><span style="font-family:Verdana;">50</span></sub><span style="font-family:Verdana;"> value for the inhibition of </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-amylase activity was found 22.6011 μg/mL. </span><i><span style="font-family:Verdana;">G.</span></i> <i><span style="font-family:Verdana;">lucidum</span></i><span styl
文摘Polycrystalline xBa<sub>0.95</sub>Sr<sub>0.05</sub>TiO<sub>3</sub>-(1 - x)BiFe<sub>0.90</sub>Gd<sub>0.10</sub>O<sub>3</sub> ceramics were prepared by standard solid state reaction technique using the solid solution of BaCO<sub>3</sub>, SrCO<sub>3</sub>, TiO<sub>2</sub>, Bi<sub>2</sub>O<sub>3</sub>, Fe<sub>2</sub>O<sub>3</sub> and Gd<sub>2</sub>O<sub>3</sub>. The compound is a BiFeO<sub>3</sub> based multiferroic material which contains both magnetic and electric properties. The synthesized ceramics noticed better properties than xBaTiO<sub>3</sub>-(1 - x)BiFeO<sub>3</sub> because of adding rare earth element Gd which have higher magnetic moment than Fe. The prepared samples were sintered at 900<span style="font-size:12px;white-space:nowrap;"><span style="font-size:12px;white-space:nowrap;">˚</span></span>C, 950<span style="font-size:12px;white-space:nowrap;"><span style="font-size:12px;white-space:nowrap;">˚</span></span>C and 1000<span style="font-size:12px;white-space:nowrap;"><span style="font-size:12px;white-space:nowrap;">˚</span></span>C for 1 h. The effect of sintering temperature on density of the compound, complex initial permeability, dielectric properties and complex impedance analysis was reported in this article. Density of the ceramics was found to be enhanced with the rise in sintering temperature which implied porosity of the compound decreased when sintering temperature was increased. Enhanced complex initial permeability was noticed for the samples up to 950<span style="font-size:12px;white-space:nowrap;"><span style="font-size:12px;white-space:nowrap;">˚</span></span>C and this might be attributed to reducing the motion of domain wall when the ceramics were sintered above 950<span style="font-size:12px;white-space:nowrap;"><span style="font-size:12px;white-space:nowrap;">˚</span></span>C. Value of dielectric constant increased whereas dielectric loss decreased and these modifications might be expected because of changing density and grain size due to the variation of si
文摘Mangrove soils are well known for their high capacity of storing organic carbon (SOC) in various pools;however, a relatively small change in SOC pools could cause significant impacts on greenhouse gas concentrations. Thus, for an in-depth understanding of SOC distribution and stock to predict the role of Sundarbans mangrove in mitigating global warming and greenhouse effects, different extraction methods were employed to fractionate the SOC of Sundarbans soils into cold-water (CWSC) and hot-water (HWSC) soluble, moderately labile (MLF), microbial biomass carbon (MBC), and resistant fractions (RF) using a newly developed modified-method. A significant variation in total SOC (p < 0.001), SOC stock (p < 0.001) and soil bulk density (p < 0.05) at the Sundarbans mangrove forest were observed. In most soils, bulk density increased from the surface to 100 cm depth. The total SOC concentrations were higher in most surface soils and ranged from 1.21% ± 0.02% to 8.19% ± 0.09%. However, C in lower layers may be more resistant than that of upper soils because of differences in compositions, sources and environmental conditions. SOC was predominately associated with the resistant fraction (81% - 97%), followed by MLF (2% - 10%), HWSC (1% - 4%), MBC (~0% - 4%), and CWSC (~0% - 3%). The significant positive correlations between different C fractions suggested that C pools are interdependent and need proper management plans to increase these pools in Sundarbans soils. The SOC stock of the studied areas ranged between 16.75 ± 3.83 to 135.12 ± 28.61 kg·C·m<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>2</sup> in 1 m soil profile and has an average of 31.80 kg·C·m<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>2</sup>. The substratum soils had more carbon than the upper layers in the Sundarbans wetland due to burial and preservation of carbon by frequent tidal inundation. A higher SOC stock in the soil profile and its primary associ
文摘Zinc Sulfide (ZnS) thin film has attracted increasing attention due to their potential applications in the new generation of nano-electronics and opto-electronics devices. The physical and chemical properties of ZnS have outstanding quality for different applications. Moreover, ZnS doped with various elements are creating a new era for both academic research and industrial applications. So, the optical properties of modified ZnS thin film will help us to find a suitable doping element for convenient deposition which may enhance the conductance and transmitting properties of the film. This review work has been carried out to explore the four-modification elements that constitute Cu, Ni, Co & Fe as descending order of atomic number corresponding to Zn, along with some potential applications considering the recent research work with other doping elements too such as Al, C, Pt etc. For example, FE, FET, Catalytic, Solar cell, Electroluminescence, Fuel cell, different sensors (Chemical sensors, Bio-sensors, Humidity sensors, light sensors, UV light sensors) and nanogenerators use ZnS thin film.
文摘The literature gap in microfinance paradox of double bottom line(financial performance vs.outreach)has always been an interesting area of research.This paper proposes a theoretical model most suitable for Islamic Microfinance Institutions(MFIs)which enables Islamic MFIs’to operate together with the existing financial models compliant with Islamic Shariah Law.This model is based on a distributed verification/decision-making process that might be realized(but not necessary)through block-chain.Among the available distributed verification techniques,blockchain technology is an attractive emerging computing paradigm due to its decentralized,immutable,shared,and secure data structure characteristics.This model proposes three significant propositions.First,sharing information through blockchain will allow a transparent network in MFI operations,which will raise confidence for donors resulting in a causal effect of a relatively lower profit rate to be charged by the MFIs.Second,the consensus mechanism will enable risk-sharing,a character of Islamic finance;thus,the MFIs will operate without any collateral for low-risk firms.Third,the double bottom line of MFIs’long-lasting paradox would be solved.As for practical implication of this proposed model,the causal impact of lower cost investment by the lenders would increase social welfare because of no collateral and no initial wealth requirement.The proposed model proposes a credit rationing approach where profit can be negative.No collateral will be used when calculating the creditworthiness of a borrower.
文摘The impact of Cr3+ ion on the magnetic properties of Mn0.50Zn0.50CrxFe2-xO4 (with x = 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5) has been studied. Ferrite samples were synthesized by combustion method and sintered at various temperatures (1250°C, 1300°C and 1350°C). The structural properties were investigated by means of X-ray diffraction patterns and indicated that the samples possess single phase cubic spinel structure. The lattice parameter decreases with the increase in Cr3+ content, as the ionic radius of Cr3+ ion is smaller than that of Fe3+. The average grain size (D), bulk density (ρB) and initial permeability (μi’ )decreases with increase in Cr3+ content whereas porosity follows its opposite trend. The ρB was found to increase with increase in Cr3+ content as the sintering temperature (Ts) is increased from 1250°C to 1350°C. The Ts affects the densification, grain growth and (μi’ ) of the samples. The (μi’ ) strongly depends on average grain size, density and intragranular porosity. The B-H loops of the compositions were measured at room temperature. The saturation magnetization (Ms), coercivity (Hc) and hysteresis losses were studied as a function of Cr3+ content. The Ms was found to decrease with the increase of Cr3+ content, which is attributed to the dilution of A-B interaction.
文摘Since anemia is one of the most skyrocketed public health problems worldwide, an investigation has thus been conducted to assess the prevalence and associated factors of anemia among the pregnant women receiving antenatal care (ANC) at Fatima Hospital in Jashore, Bangladesh. Facility-based cross-sectional study was carried out among 384 pregnant women at Fatima hospital, Bangladesh from February to April, 2019. Data were obtained using a structured questionnaire and participant’s current medical record card. Binary logistic regression analysis was used to identify factors associated with anemia and a P-value < 0.05 was considered as statistically significance. The overall prevalence of anemia among pregnant women was 58.9% (226/384). Out of 226 anemic pregnant mothers, 36.3% (82/226) were mildly anemic, 62.4% (141/226) were moderately anemic and 1.3% (3/384) was severely anemic. Binary logistic regression analysis revealed that the following variables were significantly associated with anemia: Monthly family income (11,000 - 20,000 Taka) [AOR (95% CI) = 0.45 (0.21 - 0.98)], Family size (joint) [AOR (95% CI) = 1.59 (1.03 - 2.45)], Gestational age (third trimester) [AOR (95% CI) = 2.18 (1.40 - 3.40)], birth spacing < 2 years [AOR (95% CI) = 2.87 (1.51 - 5.44)], Excessive blood loss during previous surgery (Yes) [AOR (95% CI) = 2.08 (1.14 - 4.17)], Food group eaten 24 hours (1 - 4 groups) [AOR (95% CI) = 3.43 (1.84 - 6.39)], Breakfast regularly (No) [AOR (95% CI) = 3.64 (1.36 - 9.75)]. The results obtained showed that the prevalence of anemia among pregnant women is severe at Fatima Hospital in Jashore, Bangladesh.
文摘Characterization of carbonaceous species from the particulate matters (PM) after combustion of seven commonly used biomass species, albizia tree (Albizia julibrissin), dry leaves (mahogany tree), jackfruit tree (Artocarpus heterophyllus), rain tree (Samanea saman), mahogany tree (Swietenia mahogany), cow dung and mango tree (Mangifer aindica) was done. PM samples were collected on quartz fiber filters emitted from biomass burning in a typical rural cooking stove. PM loaded filters were characterized with scanning electron microscope (SEM) for surface morphology, fourier transform infrared (FTIR) to determine the functional group of organic compounds. Black carbon (BC) and brown carbon (BrC) concentrations were determined with Aethalometer. A TOC analyzer was used to determine the total organic carbon (TOC) present in the biomass samples. The surface morphology was almost similar for all biomass burning PM samples. The average concentrations of BC and BrC were 5.85 ± 4.40 and 13.0 ± 8.80 μg·mDž, respectively. The emission factors of BC and BrC were 1.08 ± 0.89 and 2.35 ± 1.67 mg·gǃ, respectively. Concentration of BC was the highest in dry leaves and the lowest in mango tree. The emission factors of the determined biomass followed the sequence-dry leaves of mahogany > albizia tree > jackfruit tree > rain tree > cow dung > mahogany tree > mango tree. PM from mango tree had lower emissions compared to the other biomass species used in this study.
文摘Y-type hexagonal ferrites with the nominal chemical composition Ba2Ni2-xZnxFe12O22 (0.0 ≤ x ≤ 0.6 with a step of 0.1) have been synthesized by the conventional solid state reaction method and sintered in the temperature range 1150℃-1250℃ to study their structural and magnetic properties. The aim of the present work is to increase the magnetic properties of Y-type hexaferrites by Zn substitution. X-ray diffraction analysis confirms the formation of the hexagonal phase. The effect of chemical composition on the lattice parameter, density and porosity is studied. The lattice parameter increases with Zn substitution. The density increases with Zn substitution up to a certain level and after that density decreases. The ac magnetic properties of the hexaferrites sintered at temperature 1200℃ are characterized within the frequency range 100 kHz -120 MHz. The real part (μi') of the complex initial permeability for different compositions indicates that μi' decreases with increase in frequency. The permeability increases with the increase in Zn content, reaches a maximum value and then decreases with further increase in Zn content. Magnetization has been measured using the Superconducting Quantum Interference Device (SQUID) magnetometer. The saturation magnetization is observed to be maximum at x = 0.1 and then decreases with Zn content for x > 0.1. From the M-H curve it is clear that at room temperature the polycrystalline Ba2Ni2-xZnxFe12O22 compositions are in ferrimagnetic state.
文摘Objective C/eome rutidosperma （Capparidaceae）, commonly known as ＂Fringed Spider Flower＂, is a medicinal plant found in Southeast Asia. C. rutidosperma is used in folk medicine for diuretic, laxative, analgesic, anti-inflammatory, antipyretic, antimicrobial, anti-oxidant, hypoglycemic, and anthelmintic activities. We have evaluated the anti-nociceptive properties of methanol extract from C. rutidosperma （MECR） in vivo. Methods Thermal method （hot plate test and tail flick test） was induced to judge the anti-inflammatory effect and couple of chemical method also used （formalin induced licking test; writhing test carried by acetic acid） to evaluate analgesic effect. Both of these tests were made over animal models, like mice and rats. Two different doses （1 O0 and 200 mg/kg） were used for each case of test, while morphine sulphate （5mg/kg, ip） was used as reference drug. Results MECR demonstrated the significantly anti-nociceptive activity in the analgesic and anti-inflammatory tests by reducing nociception in mice models （P 〈 0.001）. in the hot-plate and tail-flick tests, MECR significantly elongated the time to response to the thermal stimuli （100 and 200 mg/kg with P 〈 0.05, 0.001）. The remarkable increase in the latency was observed at 90 and 120 min. In acetic acid-induced writhing test and formalin induced licking test for anti-inflammatory activity, MECR at 100 and 200 mg/kg doses exhibited significant （P〈 0.001） reduction of writhing and licking response. Conclusion The anti-inflammatory and analgesic effects of C. rutidosperma propose that this effect may be a result of both peripheral and central mechanisms. Further study is required to ensure the proper mechanism of action as well as the active ingredient.
文摘Mn0.50-xZn0.50CuxFe2O4 (where x = 0.0 - 0.3) ferrites have been synthesized by auto combustion method. X-ray diffraction patterns reveal that all compositions are of single phase cubic spinel structure. The lattice parameter decreases with the increase in Cu2+ content obeying the Vegard’s law. The bulk density, average grain size, initial permeability, Néel temperature and saturation magnetic induction of Mn0.50-xZn0.50CuxFe2O4 increased with increasing Cu2+content. It is observed that both density and initial permeability increase with increasing sintering temperature. The maximum initial permeability is found to be 1061 which is almost four times greater than that of the parent composition. The resonance frequency of all the samples shifts towards the lower frequency as the permeability increases with Cu2+ content. It is observed from B-H loops of Mn0.50-xZn0.50CuxFe2O4 that coercivity decreases and retentivity increases with Cu2+ content. Possible explanations for the observed magnetic properties with various Cu2+ contents are discussed.
文摘This study investigated distribution of HLA alleles (HLADRB1*01, *03, *04, *07, HLA-DQB1*0201, *0301/4) in 34 healthy controls and 57 rheumatoid arthritis (RA) patients in a Bangladeshi population and correlated the genotypic frequencies with clinical parameters. Frequency distribution of HLA-DRB1*04 (34%) and HLA-DRB1*01 (32%) were the highest followed by HLA-DQB1*0301/4 (29%) and HLA-DQB1*0201 (26%) in RA patients while HLA-DRB1*03 (12%) had lowest frequency. Plasma level of anti-CCP and rheumatoid factor antibodies confirmed diagnosis of RA patients that varied significantly between patients and healthy controls. Likewise, plasma levels of C-reactive protein, triglycerides, cholesterol, HDL-cholesterol and activities of AST and ALT exhibited significant variation between the two groups. In contrast, the levels of glucose, total protein, uric acid, LDL-cholesterol and plasma activity of ALP in RA patients had no significant deviations from healthy controls. Relationship between HLA genotype frequency and clinical parameters revealed that the mean levels of anti-CCP and rheumatoid factor antibodies were highest in the patients harboring HLA-DRB1*04 allele. These findings underpin the correlation between HLA genotype with clinical markers of RA which are indicative of disease severity. The positive correlation of these markers with certain HLA genes may be used to identify susceptible individuals who are likely to have RA in Bangladeshi population.
基金acknowledge CASR of Bangladesh University of Engineering and Technology(BUET) for financial support for this research
文摘Structural and various electrical properties of polycrystalline Ca0.5＋xNd0,5-x（Ti0.5Fe0.5）O3, prepared by standard solid state reaction technique, were studied. Formation of single phase orthorhombic structure of the compositions was confirmed by X-ray diffraction study. The composition dependence of lattice parameters, density and microstructural study show that they vary significantly with Ca content. The dielectric measurements were carried out at room temperature as function of frequency and composition. The experimental results reveal that the dielectric constant （ε′） increases with increasing Ca content. Similar behavior is observed for the dielectric loss （tanδ） and ac conductivity （σac）. In complex impedance analysis it is observed that the real part （Z′） vs imaginary part （Z″） graph exhibits a tendency of formation of a single semicircular arc for each composition of samples. Different parameters were determined by fitting the experimental data in Cole-Cole empirical formula. A dominance of grain boundary resistance （Rgb） is observed. The Rgb decreases with increasing Ca content. The high ε′ observed in present samples are suitable for fabrication of devices.
文摘The electrical properties of Ni_(0.27)Cu_(0.10)Zn_(0.63)Fe_(2)O_(4)(NCZF)prepared from auto combustion synthesis of ferrite powders have been studied by impedance and modulus spectroscopy.We studied frequency and temperature dependencies of impedance and electric modulus of NCZF in a wide frequency range(20 Hz-5 MHz)at different measuring temperatures T_(SM)(30-225℃).The complex impedance spectra clearly showed both grain and grain boundary effects on the electrical properties.The observed impedance spectra indicated that the magnitude of grain boundary resistance R_(gb) becomes more prominent compared to grain resistance R_(b) at room temperature,and with the increase in T_(SM),R_(gb) decreases faster than the intrinsic R_(b).The frequency response of the imaginary part of impedance showed relaxation behavior at every T_(SM),and the relaxation frequency variation with T_(SM) appeared to be of Arrhenius nature and the activation energy has been estimated to be 0.37 eV.A complex modulus spectrum was used to understand the mechanism of the electrical transport process,which indicated that a non-Debye type of conductivity relaxation characterizes this material.
基金financial support for this research. One of the authors M.J. Miah thanks the Ministry of National Science, Information & Communication Technology (NST), Government of the People’s Republic of Bangladesh for providing fellowship
文摘xBa_（0.95）Sr_（0.05）TiO_3–（1-x）BiFe_（0.9）Gd_（0.1）O_3[x BST–（1-x）BFGO]（x = 0.00, 0.10, 0.20 and 0.25） multiferroic ceramics were prepared by the standard solid-state reaction technique. Structural characterization was performed by X-ray diffraction. All the samples showed rhombohedral distorted perovskite structure. Surface morphology of the ceramics was studied by the field emission scanning electron microscope（FESEM）. From the FESEM observation, the grain size was observed to be decreased with increasing BST content. Enhanced magnetic properties were observed in BFGO with the increase in BST content because of large lattice distortion. The complex initial permeability increased with the increasing of BST content. The study of dielectric properties showed that the dielectric constant increased, whereas dielectric loss decreased with increasing of BST content due to the reduction of oxygen vacancies. An analysis of the electric impedance and modulus with frequency was performed at different temperatures. Non-Debye-type relaxation processes occur in the compound which was confirmed from the nature of the Cole–Cole plot. The DC conductivity was found to increase with the rise in temperature which indicates the semiconducting behavior of the compound with characteristics of the negative temperature coefficient of resistance. The activation energy, responsible for the relaxation determined from the modulus spectra（0.246 eV）, was found to be almost same as the value obtained from the impedance study（0.240 eV）, indicating that charge carriers overcome the same energy barrier during relaxation. The frequency response of imaginary parts of electric impedance and modulus suggested that the relaxation in xB ST–（1-x）BFGO ceramics follows the same mechanism at various temperatures.
基金Supported by the CASR of Bangladesh University of Engineering and Technology(BUET).for this research。
文摘Various polycrystalline Ba1-x Lax (Ti0.5 Fe0.5 )O3 are prepared by using the standard solid state reaction technique.Pellet shaped samples prepared from each composition are sintered at 1200℃ for 5 h.X-ray diffraction patterns of these compositions confirm the formation of a single phase perovskite structure.The lattice parameters are decreased but the average grain size increases with the increase of La content.The dielectric constant,dielectric loss and ac conductivity are studied as a function of frequency for various compositions,and their behaviors are explained on the basis of the Maxwell-Wagner model A three-times enhancement of the dielectric constant is observed with the increase of La content.
