A significant amount of aluminum dross is available as a waste in foundry industries in Bangladesh. In this study, alumina was ex- tracted from aluminum dross collected from two foundry industries situated in Dhamrai ...A significant amount of aluminum dross is available as a waste in foundry industries in Bangladesh. In this study, alumina was ex- tracted from aluminum dross collected from two foundry industries situated in Dhamrai and Manikgang, near the capital city, Dhaka. Alu- minum dross samples were found to approximately contain 75wt% A1203 and 12wt% SIO2. An acid dissolution process was used to recover the alumina value from the dross. The effects of various parameters, e.g., temperature, acid concentration, and leaching time, on the extrac- tion of alumina were studied to optimize the dissolution process. First, AI(OH)3 was produced in the form of a gel. Calcination of the AI(OH)3 gel at 1000℃, 1200℃, and 1400℃ for 2 h produced O-AlcOa, (t~+O)-A1203, and u-alumina powder, respectively. Thermal charac- terization of the AI(OH)3 gel was performed by thermogravimetric/differential thermal analysis (TG/DTA) and differential scanning calo- rimetry (DSC). The phases and crystallite size of the alumina were determined by X-ray diffraction analysis. The dimensions of the alumina were found to be on the nano level. The chemical compositions of the aluminum dross and alumina were determined by X-ray fluorescence (XRF) spectroscopy. The microstructure and morphology of the alumina were studied with scanning electron microscopy. The purity of the alumina extracted in this study was found to be 99.0%. Thus, it is expected that the obtained alumina powders can be potentially utilized as biomaterials.展开更多
Nowadays, use of alternative and complementary therapies with mainstream medicine has gained the momentum. Aromatherapy is one of the complementary therapies which use essential oils as the major therapeutic agents to...Nowadays, use of alternative and complementary therapies with mainstream medicine has gained the momentum. Aromatherapy is one of the complementary therapies which use essential oils as the major therapeutic agents to treat several diseases. The essential or volatile oils are extracted from the flowers, barks, stem, leaves, roots, fruits and other parts of the plant by various methods. It came into existence after the scientists deciphered the antiseptic and skin permeability properties of essential oils. Inhalation, local application and baths are the major methods used in aromatherapy that utilize these oils to penetrate the human skin surface with marked aura. Once the oils are in the system, they remodulate themselves and work in a friendly manner at the site of malfunction or at the affected area. This type of therapy utilizes various permutation and combinations to get relief from numerous ailments like depression, indigestion, headache, insomnia, muscular pain, respiratory problems, skin ailments, swollen joints, urine associated complications etc. The essential oils are found to be more beneficial when other aspects of life and diet are given due consideration. This review explores the information available in the literature regarding therapeutic, medical, cosmetic, psychological, olfactory, massage aromatherapy, safety issues and different plants used in aromatherapy. All the available information was compiled from electronic databases such as Academic Journals, Ethnobotany, Google Scholar, PubM ed, Science Direct, Web of Science, and library search.展开更多
Over the span of years, improvements over various synthesis methods of graphene are constantly pursued to provide safer and more effective alternatives. Though the extraction of graphene through Hummers method is one ...Over the span of years, improvements over various synthesis methods of graphene are constantly pursued to provide safer and more effective alternatives. Though the extraction of graphene through Hummers method is one of the oldest techniques yet it is one of the most suitable methods for the formation of bulk graphene. Graphene can be obtained in the form of reduced Graphite oxide, sometimes also referred as Graphene oxide. The effectiveness of this oxidation process can be evaluated by the magnitude of carbon/oxygen ratio of the obtained graphene. Here, graphene oxide (GO) was prepared by oxidizing the purified natural flake graphite (NFG) by a modified Hummers method. The attempts have been made to synthesize GO having few layers by using a modified Hummers method where the amount of NaNO3 has been decreased, and the amount of KMnO4 is increased. The reaction has been performed in a 9:1 (by volume) mixture of H2SO4/H3PO4. This modification is successful in increasing the reaction yield and reducing the toxic gas evolution while using a varied proportion of KMnO4 and H2SO4 as those required by Hummers method. A new component of K2S2O8 has been introduced to the reaction system to maintain the pH value. Reduced graphene oxide (rGO) was thereafter extracted by thermal modification of GO. Here, GO has been used as a precursor for graphene synthesis by thermal reduction processes. The results of FTIR and Raman spectroscopy analysis show that the NFG when oxidized by strong oxidants like KMnO4 and NaNO3, introduced oxygen atoms into the graphite layers and formed bonds like C=O, C-H, COOH and C-O-C with the carbon atoms in the graphite layers. The structure and morphology of both GO and rGO were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy, Raman spectroscopy, Brunauer-Emmett-Teller (BET) surface area analysis and differential scanning calorimetry (展开更多
Nigella sativa(N.sativa)(Family Ranunculaceae)is a widely used medicinal plant throughout the world.It is very popular in various traditional systems of medicine like Unani and Tibb,Ayurveda and Siddha.Seeds and oil h...Nigella sativa(N.sativa)(Family Ranunculaceae)is a widely used medicinal plant throughout the world.It is very popular in various traditional systems of medicine like Unani and Tibb,Ayurveda and Siddha.Seeds and oil have a long history of folklore usage in various systems of medicines and food.The seeds of N.saliva have been widely used in the treatment of different diseases and ailments.In Islamic literature,it is considered as one of the greatest forms of healing medicine.It has been recommended for using on regular basis in Tibb-e-Nabwi(Prophetic Medicine).It has been widely used as antihypertensive,liver tonics,diuretics,digestive,anti-diarrheal,appetite stimulant,analgesics,anti-bacterial and in skin disorders.Extensive studies on N.sativa have been carried out by various researchers and a wide spectrum of its pharmacological actions have been explored which may include antidiabetic,anticancer,immunomodulator,analgesic,antimicrobial,anti-inflammatory,spasmolytic,bronchodilator,hepato-protective,renal protective,gaslro-prolective,antioxidant properties,etc.Due to its miraculous power of healing,N.sativa has got the place among the top ranked evidence based herbal medicines.This is also revealed that most of the therapeutic,properties of this plant are due to the presence of thymoquinone which is major bioactive component of the essential oil.The present review is an effort to provide a detailed survey of the literature on scientific researches of pharmacognostical characteristics,chemical composition and pharmacological activities of the seeds of this plant.展开更多
Although insulin resistance(IR)is strongly associated with nonalcoholic fatty liver disease(NAFLD),the association of IR and NAFLD is not universal and correlation between IR and severity of NAFLD is still controversi...Although insulin resistance(IR)is strongly associated with nonalcoholic fatty liver disease(NAFLD),the association of IR and NAFLD is not universal and correlation between IR and severity of NAFLD is still controversial.In this review,we summarize recent evidence that partially dissociates insulin resistance from NAFLD.It has also been reported that single-nucleotide polymorphisms in the diacylglycerol acyltransferase gene,rather than IR,account for the variability in liver fat content.Polymorphisms of the patatin-like phospholipase 3 gene have also been reported to be associated with NAFLD without metabolic syndrome,which suggests that genetic conditions that promote the development of fatty changes in the liver may occur independently of IR.Moreover,environmental factors such as nutrition and physical activity as well as small intestinal bacterial overgrowth have been linked to the pathogenesis of NAFLD,although some of the data are conflicting.Therefore,findings from both genetically engineered animal models and humans with genetic conditions,as well as recent studies that have explored the role of environmental factors,have confirmed the view that NAFLD is a polygenic disease process caused by both genetic and environmental factors.Therefore,IR is not the sole predictor of the pathogenesis of NAFLD.展开更多
Acute on chronic liver failure(ACLF) was first described in 1995 as a clinical syndrome distinct to classic acute decompensation.Characterized by complications of decompensation,ACLF occurs on a background of chroni...Acute on chronic liver failure(ACLF) was first described in 1995 as a clinical syndrome distinct to classic acute decompensation.Characterized by complications of decompensation,ACLF occurs on a background of chronic liver dysfunction and is associated with high rates of organ failure and significant short-term mortality estimated between45%and 90%.Despite the clinical relevance of the condition,it still remains largely undefined with continued disagreement regarding its precise etiological factors,clinical course,prognostic criteria and management pathways.It is concerning that,despite our relative lack of understanding of the condition,the burden of ACLF among cirrhotic patients remains significant with an estimated prevalence of 30.9%.This paper highlights our current understanding of ACLF,including its etiology,diagnostic and prognostic criteria and pathophysiology.It is evident that further refinement of the ACLF classification system is required in order to detect high-risk patients and improve short-term mortality rates.The field of metabolomics certainly warrants investigation to enhance diagnostic and prognostic parameters,while the use of granulocyte-colony stimulating factor is a promising future therapeutic intervention for patients with ACLF.展开更多
The capability of carbon nanotubes (CNTs) to adsorb lead (Pb) in aqueous solution was investigated. Batch mode adsorption experiment was conducted to determine the effects of pH, agitation speed, CNTs dosage and c...The capability of carbon nanotubes (CNTs) to adsorb lead (Pb) in aqueous solution was investigated. Batch mode adsorption experiment was conducted to determine the effects of pH, agitation speed, CNTs dosage and contact time. The removal of Pb(II) reached maximum value 85% or 83% at pH 5 or 40 mg/L of CNTs, respectively. Higher correlation coefficients from Langmuir isotherm model indicates the strong adsorptions of Pb(II) on the surface of CNTs (adsorption capacity Xm = 102.04 mg/g). The results indicates that the highest percentage removal of Pb (96.03%) can be achieved at pH 5, 40 mg/L of CNTs, contact time 80 min, and agitation speed 50 r/min.展开更多
AIM: To define optimum management of the pyogenic liver abscess and assess new trends in treatment. METHODS: One hundred and sixty nine patients with pyogenic liver abscess managed at Sher-i-Kashmir In- stitute of Med...AIM: To define optimum management of the pyogenic liver abscess and assess new trends in treatment. METHODS: One hundred and sixty nine patients with pyogenic liver abscess managed at Sher-i-Kashmir In- stitute of Medical Sciences, Srinagar, Kashmir (India) from July 2001 to August 2006 were studied to evaluate and define the optimum treatment. RESULTS: Mortality in the surgically treated group of patients was 9.4% (12/119), while those treated non-surgically had a fatality rate of 16.66% (7/42). Multiple liver abscesses treated surgically had a surprisingly low mortality of 30%. The biliary tract (64.97%) was the most common cause of liver abscess. Multiple abscesses, mixed organisms and abscess complications are all associated with a significantly increased mortality. However, the lethality of the primary disease process was the most important factor in determining survival.CONCLUSION: Transperitoneal surgical drainage and antibiotics are the mainstay of treatment. Percutaneous drainage is recommended for high risk patients only.展开更多
The adsorption capacity of activated carbon produced from oil palm empty fruit bunches through removal of 2,4-dichlorophenol from aqueous solution was carried out in the laboratory. The activated carbon was produced b...The adsorption capacity of activated carbon produced from oil palm empty fruit bunches through removal of 2,4-dichlorophenol from aqueous solution was carried out in the laboratory. The activated carbon was produced by thermal activation of activation time with 30 min at 800℃. The adsorption process conditions were determined with the statistical optimization followed by central composite design. A developed polynomial model for operating conditions of adsorption process indicated that the optimum conditions for maximum adsorption of phenolic compound were: agitation rate of 100 r/min, contact time of 8 h, initial adsorbate concentration of 250 mg/L and pH 4. Adsorption isotherms were conducted to evaluate biosorption process. Langmuir isotherm was more favorable (R^2=0.93) for removal of 2,4-dichlorophenol by the activated carbon rather than Freundlich isotherm (R^2=0.88).展开更多
In this article, a novel (G'/G)-expansion method is proposed to search for the traveling wave solutions of nonlinear evolution equations. We construct abundant traveling wave solutions involving parameters to the B...In this article, a novel (G'/G)-expansion method is proposed to search for the traveling wave solutions of nonlinear evolution equations. We construct abundant traveling wave solutions involving parameters to the Boussinesq equation by means of the suggested method. The performance of the method is reliable and useful, and gives more general exact solutions than the existing methods. The new (G'/G)-expansion method provides not only more general forms of solutions but also cuspon, peakon, soliton, and periodic waves.展开更多
Postoperative sleep disturbance is a common occurrence with significant adverse effects on patients including delayed recovery,impairment of cognitive function,pain sensitivity and cardiovascular events.The developmen...Postoperative sleep disturbance is a common occurrence with significant adverse effects on patients including delayed recovery,impairment of cognitive function,pain sensitivity and cardiovascular events.The development of postoperative sleep disturbance is multifactorial and involves the surgical inflammatory response,the severity of surgical trauma,pain,anxiety,the use of anesthetics and environmental factors such as nocturnal noise and light levels.Many of these factors can be managed perioperatively to minimize the deleterious impact on sleep.Pharmacological and non-pharmacological treatment strategies for postoperative sleep disturbance include dexmedetomidine,zolpidem,melatonin,enhanced recovery after surgery(ERAS) protocol and controlling of environmental noise and light levels.It is likely that a combination of pharmacological and non-pharmacological therapies will have the greatest impact;however,further research is required before their use can be routinely recommended.展开更多
A comprehensive landslide inventory and susceptibility maps are prerequisite for developing and implementing landslide mitigation strategies. Landslide susceptibility maps for the landslides prone regions in northern ...A comprehensive landslide inventory and susceptibility maps are prerequisite for developing and implementing landslide mitigation strategies. Landslide susceptibility maps for the landslides prone regions in northern Pakistan are rarely available. The Hunza-Nagar valley in northern Pakistan is known for its frequent and devastating landslides. In this paper, we have developed a landslide inventory map for Hunza-Nagar valley by using the visual interpretation of the SPOT-5 satellite imagery and mapped a total of 172 landslides. The landslide inventory was subsequently divided into modelling and validation data sets. For the development of landslide susceptibility map seven discrete landslide causative factors were correlated with the landslide inventory map using weight of evidence and frequency ratio statistical models. Four different models of conditional independence were used for the selection of landslide causative factors. The produced landslides susceptibility maps were validated by the success rate and area under curves criteria. The prediction power of the models was also validated with the prediction rate curve. The validation results shows that the success rate curves of the weight of evidence and the frequency models are 82% and 79%, respectively. The prediction accuracy results obtained from this study are 84% for weight of evidence model and 80% for the frequency ratio model. Finally, the landslide susceptibility index maps were classified into five different varying susceptibility zones. The validation and prediction result indicates that the weight of evidence and frequency ratio model are reliable to produce an accurate landslide susceptibility map, which may be helpful for landslides management strategies.展开更多
AIM: To explore the prevalence and risk factors for nonalcoholic steatohepatitis (NASH) in nonalcoholic fatty liver disease (NAFLD) patients. METHODS: We have included 493 patients with sonographic evidence of a fatt... AIM: To explore the prevalence and risk factors for nonalcoholic steatohepatitis (NASH) in nonalcoholic fatty liver disease (NAFLD) patients. METHODS: We have included 493 patients with sonographic evidence of a fatty change, and 177 of these individuals were evaluated and confirmed after liver biopsy. The exclusion criteria consisted of significant alcohol abuse (【 20 g daily), evidence of hepatitis B and C, evidence of drug-induced fatty liver disease and other specific liver diseases such as hemochromatosis, Wilson’s disease or autoimmune liver disease. The patients were assessed for metabolic syndrome, and biochemical, anthropometric and histopathological evaluations were carried out. The degree of disease activity in the NAFLD patients was evaluated using the NAFLD Activity Score. The data were analyzed by SPSS, version 16.0. RESULTS: Females predominated among the study participants (250, 57.0%), and the mean age was 40.8 ± 10.2 years. The numbers of overweight, obeseⅠ and obese Ⅱ patients were 58 (13.2%), 237 (53.9%) and 93 (21.2%), respectively. However, there were 422 (96.2%) centrally obese patients. NASH was absent in 10 (5.6%) cases, borderline in 92 (52.6%) cases and present in 75 (42.4%) cases. The presence of diabetes could significantly (P = 0.001) differentiate NASH from simple steatosis. The following parameters did not influence the development of NASH: age, sex, basal metabolic index, waist circumference, serum high-density lipoprotein, triglyceride, insulin resistance index, hypertension and metabolic syndrome. The serum gammaglutamyl transpeptidase (GGT) level was significantly higher (P = 0.05, 51.7 ± 32.8 and 40.4 ± 22.6 U/L) in the NASH patients, with a sensitivity of 45% and a specificity of only 68%. The serum alanine aminotransferase and aspartate aminotransferase levels were not able to predict NASH. CONCLUSION: Females were the predominant sufferers of NAFLD in Bangladesh. The prevalence of NASH was high. Diabetes was found to be the main culprit in developing NASH. GGT 展开更多
Intractable delays occur in air traffic due to the imbalance between ever-increasing air traffic demand and limited airspace capacity.As air traffic is associated with complex air transport systems,delays can be magni...Intractable delays occur in air traffic due to the imbalance between ever-increasing air traffic demand and limited airspace capacity.As air traffic is associated with complex air transport systems,delays can be magnified and propagated throughout these systems,resulting in the emergent behavior known as delay propagation.An understanding of delay propagation dynamics is pertinent to modern air traffic management.In this work,we present a complex network perspective of delay propagation dynamics.Specifically,we model air traffic scenarios using spatial–temporal networks with airports as the nodes.To establish the dynamic edges between the nodes,we develop a delay propagation method and apply it to a given set of air traffic schedules.Based on the constructed spatial-temporal networks,we suggest three metrics-magnitude,severity,and speed-to gauge delay propagation dynamics.To validate the effectiveness of the proposed method,we carry out case studies on domestic flights in the Southeastern Asia region(SAR)and the United States.Experiments demonstrate that the propagation magnitude in terms of the number of flights affected by delay propagation and the amount of propagated delays for the US traffic are respectively five and ten times those of the SAR.Experiments further reveal that the propagation speed for US traffic is eight times faster than that of the SAR.The delay propagation dynamics reveal that about six hub airports in the SAR have significant propagated delays,while the situation in the United States is considerably worse,with a corresponding number of around 16.This work provides a potent tool for tracing the evolution of air traffic delays.展开更多
Clinacanthus nutans Lindau is known as snake grass belonging to the Acanlhaceae family.This plant has diverse and potential medicinal uses in traditional herbal medicine for treating skin rashes,insects and snake bite...Clinacanthus nutans Lindau is known as snake grass belonging to the Acanlhaceae family.This plant has diverse and potential medicinal uses in traditional herbal medicine for treating skin rashes,insects and snake bites,lesions caused by herpes simplex virus,diabetes,and gout in Malaysia.Indonesia.Thailand and China.Phylochemieal investigations documented the varied contents of bioaclive compounds from litis plant namely flavonoids,glycosides,glycoglyeerolipids.cerebrosides and monoacylmonogalatosylglycerol.The pharmacological experiment proved that various types of extracts and pure compounds from this species exhibited a broad range of biological properties such as anti-inflammatory,antiviral,antioxidant,and anti-diabetic activities.The lindings of toxicity study showed that extracts from this plant did not show any toxicity thus it can be used as strong therapeutic agents for specific diseased conditions.However,further experiments on chemical components and their mode of action showing biological activities are required to elucidate the complete phytochemical profile and assess to confirm their suitability tor future drugs.This review summarizes the medicinal uses,phytochemistry and pharmacology of this plant in order to explore its therapeutic potential and gaps necessitating for prospected research work.展开更多
Objective:To investigate mosquitocidal effects of ethanolic extract of(lowers of Tagetes erecta(T.erecta) and its chloroform and petroleum ether soluble fractions against the larvae of Culex quinquefasciatus(Cx.quinqu...Objective:To investigate mosquitocidal effects of ethanolic extract of(lowers of Tagetes erecta(T.erecta) and its chloroform and petroleum ether soluble fractions against the larvae of Culex quinquefasciatus(Cx.quinquefasciatus).Methods:The fresh flowers of T.erecta were extracted in cold with ethanol(5.0 L) and after concentration,the ethanol extract was fractionated with chloroform and petroleum ether to afford a brownish syrupy suspension of ethanol extract(50.0 g),petroleum ether soluble fraction(18.6 g) and chloroform soluble fraction(23.8 g).The larvicidal effect of ethanol extract and their solvent fractions were determined by the standard procedure of WHO against different instars of Cx.quinquefasciatus.Results:Among the tested samples the chloroform soluble fractions showed the highest toxicity and consequently,the lowest LC_(50) values(14.14 μ g/mL,17.06 μ g/mL.36.88 μ g/mL and 75.48 μ g/mL) for all the instars larvae of Cx.quinquefasciatus.The larvae showed comparative tolerance in the course of increasing age and time.Conclusions:It can be concluded that the flowers of T.erecta are very effective natural larvicide and could be useful against Cx.quinquefasciatus.展开更多
文摘A significant amount of aluminum dross is available as a waste in foundry industries in Bangladesh. In this study, alumina was ex- tracted from aluminum dross collected from two foundry industries situated in Dhamrai and Manikgang, near the capital city, Dhaka. Alu- minum dross samples were found to approximately contain 75wt% A1203 and 12wt% SIO2. An acid dissolution process was used to recover the alumina value from the dross. The effects of various parameters, e.g., temperature, acid concentration, and leaching time, on the extrac- tion of alumina were studied to optimize the dissolution process. First, AI(OH)3 was produced in the form of a gel. Calcination of the AI(OH)3 gel at 1000℃, 1200℃, and 1400℃ for 2 h produced O-AlcOa, (t~+O)-A1203, and u-alumina powder, respectively. Thermal charac- terization of the AI(OH)3 gel was performed by thermogravimetric/differential thermal analysis (TG/DTA) and differential scanning calo- rimetry (DSC). The phases and crystallite size of the alumina were determined by X-ray diffraction analysis. The dimensions of the alumina were found to be on the nano level. The chemical compositions of the aluminum dross and alumina were determined by X-ray fluorescence (XRF) spectroscopy. The microstructure and morphology of the alumina were studied with scanning electron microscopy. The purity of the alumina extracted in this study was found to be 99.0%. Thus, it is expected that the obtained alumina powders can be potentially utilized as biomaterials.
基金Funded by the Deanship of Scientific Research,King Abdulaziz University,Jeddah under grant number(G-1436-156-590)
文摘Nowadays, use of alternative and complementary therapies with mainstream medicine has gained the momentum. Aromatherapy is one of the complementary therapies which use essential oils as the major therapeutic agents to treat several diseases. The essential or volatile oils are extracted from the flowers, barks, stem, leaves, roots, fruits and other parts of the plant by various methods. It came into existence after the scientists deciphered the antiseptic and skin permeability properties of essential oils. Inhalation, local application and baths are the major methods used in aromatherapy that utilize these oils to penetrate the human skin surface with marked aura. Once the oils are in the system, they remodulate themselves and work in a friendly manner at the site of malfunction or at the affected area. This type of therapy utilizes various permutation and combinations to get relief from numerous ailments like depression, indigestion, headache, insomnia, muscular pain, respiratory problems, skin ailments, swollen joints, urine associated complications etc. The essential oils are found to be more beneficial when other aspects of life and diet are given due consideration. This review explores the information available in the literature regarding therapeutic, medical, cosmetic, psychological, olfactory, massage aromatherapy, safety issues and different plants used in aromatherapy. All the available information was compiled from electronic databases such as Academic Journals, Ethnobotany, Google Scholar, PubM ed, Science Direct, Web of Science, and library search.
文摘Over the span of years, improvements over various synthesis methods of graphene are constantly pursued to provide safer and more effective alternatives. Though the extraction of graphene through Hummers method is one of the oldest techniques yet it is one of the most suitable methods for the formation of bulk graphene. Graphene can be obtained in the form of reduced Graphite oxide, sometimes also referred as Graphene oxide. The effectiveness of this oxidation process can be evaluated by the magnitude of carbon/oxygen ratio of the obtained graphene. Here, graphene oxide (GO) was prepared by oxidizing the purified natural flake graphite (NFG) by a modified Hummers method. The attempts have been made to synthesize GO having few layers by using a modified Hummers method where the amount of NaNO3 has been decreased, and the amount of KMnO4 is increased. The reaction has been performed in a 9:1 (by volume) mixture of H2SO4/H3PO4. This modification is successful in increasing the reaction yield and reducing the toxic gas evolution while using a varied proportion of KMnO4 and H2SO4 as those required by Hummers method. A new component of K2S2O8 has been introduced to the reaction system to maintain the pH value. Reduced graphene oxide (rGO) was thereafter extracted by thermal modification of GO. Here, GO has been used as a precursor for graphene synthesis by thermal reduction processes. The results of FTIR and Raman spectroscopy analysis show that the NFG when oxidized by strong oxidants like KMnO4 and NaNO3, introduced oxygen atoms into the graphite layers and formed bonds like C=O, C-H, COOH and C-O-C with the carbon atoms in the graphite layers. The structure and morphology of both GO and rGO were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy, Raman spectroscopy, Brunauer-Emmett-Teller (BET) surface area analysis and differential scanning calorimetry (
基金Supported by Deanship of Scientific Research,King Abdulaziz University,Jeddah,Saudi Arabia(Grant No.431-044)
文摘Nigella sativa(N.sativa)(Family Ranunculaceae)is a widely used medicinal plant throughout the world.It is very popular in various traditional systems of medicine like Unani and Tibb,Ayurveda and Siddha.Seeds and oil have a long history of folklore usage in various systems of medicines and food.The seeds of N.saliva have been widely used in the treatment of different diseases and ailments.In Islamic literature,it is considered as one of the greatest forms of healing medicine.It has been recommended for using on regular basis in Tibb-e-Nabwi(Prophetic Medicine).It has been widely used as antihypertensive,liver tonics,diuretics,digestive,anti-diarrheal,appetite stimulant,analgesics,anti-bacterial and in skin disorders.Extensive studies on N.sativa have been carried out by various researchers and a wide spectrum of its pharmacological actions have been explored which may include antidiabetic,anticancer,immunomodulator,analgesic,antimicrobial,anti-inflammatory,spasmolytic,bronchodilator,hepato-protective,renal protective,gaslro-prolective,antioxidant properties,etc.Due to its miraculous power of healing,N.sativa has got the place among the top ranked evidence based herbal medicines.This is also revealed that most of the therapeutic,properties of this plant are due to the presence of thymoquinone which is major bioactive component of the essential oil.The present review is an effort to provide a detailed survey of the literature on scientific researches of pharmacognostical characteristics,chemical composition and pharmacological activities of the seeds of this plant.
文摘Although insulin resistance(IR)is strongly associated with nonalcoholic fatty liver disease(NAFLD),the association of IR and NAFLD is not universal and correlation between IR and severity of NAFLD is still controversial.In this review,we summarize recent evidence that partially dissociates insulin resistance from NAFLD.It has also been reported that single-nucleotide polymorphisms in the diacylglycerol acyltransferase gene,rather than IR,account for the variability in liver fat content.Polymorphisms of the patatin-like phospholipase 3 gene have also been reported to be associated with NAFLD without metabolic syndrome,which suggests that genetic conditions that promote the development of fatty changes in the liver may occur independently of IR.Moreover,environmental factors such as nutrition and physical activity as well as small intestinal bacterial overgrowth have been linked to the pathogenesis of NAFLD,although some of the data are conflicting.Therefore,findings from both genetically engineered animal models and humans with genetic conditions,as well as recent studies that have explored the role of environmental factors,have confirmed the view that NAFLD is a polygenic disease process caused by both genetic and environmental factors.Therefore,IR is not the sole predictor of the pathogenesis of NAFLD.
文摘Acute on chronic liver failure(ACLF) was first described in 1995 as a clinical syndrome distinct to classic acute decompensation.Characterized by complications of decompensation,ACLF occurs on a background of chronic liver dysfunction and is associated with high rates of organ failure and significant short-term mortality estimated between45%and 90%.Despite the clinical relevance of the condition,it still remains largely undefined with continued disagreement regarding its precise etiological factors,clinical course,prognostic criteria and management pathways.It is concerning that,despite our relative lack of understanding of the condition,the burden of ACLF among cirrhotic patients remains significant with an estimated prevalence of 30.9%.This paper highlights our current understanding of ACLF,including its etiology,diagnostic and prognostic criteria and pathophysiology.It is evident that further refinement of the ACLF classification system is required in order to detect high-risk patients and improve short-term mortality rates.The field of metabolomics certainly warrants investigation to enhance diagnostic and prognostic parameters,while the use of granulocyte-colony stimulating factor is a promising future therapeutic intervention for patients with ACLF.
基金the Kulliyyah of Engineering(KOE) and Department of Biotechnology Engineering,IIUM for supporting and providing the laboratory facilities
文摘The capability of carbon nanotubes (CNTs) to adsorb lead (Pb) in aqueous solution was investigated. Batch mode adsorption experiment was conducted to determine the effects of pH, agitation speed, CNTs dosage and contact time. The removal of Pb(II) reached maximum value 85% or 83% at pH 5 or 40 mg/L of CNTs, respectively. Higher correlation coefficients from Langmuir isotherm model indicates the strong adsorptions of Pb(II) on the surface of CNTs (adsorption capacity Xm = 102.04 mg/g). The results indicates that the highest percentage removal of Pb (96.03%) can be achieved at pH 5, 40 mg/L of CNTs, contact time 80 min, and agitation speed 50 r/min.
基金Supported by The Department of Surgery and Medical Records Section Sheri Kashmir Institute of Medical Sciences, Srinagar, Kashmir, India
文摘AIM: To define optimum management of the pyogenic liver abscess and assess new trends in treatment. METHODS: One hundred and sixty nine patients with pyogenic liver abscess managed at Sher-i-Kashmir In- stitute of Medical Sciences, Srinagar, Kashmir (India) from July 2001 to August 2006 were studied to evaluate and define the optimum treatment. RESULTS: Mortality in the surgically treated group of patients was 9.4% (12/119), while those treated non-surgically had a fatality rate of 16.66% (7/42). Multiple liver abscesses treated surgically had a surprisingly low mortality of 30%. The biliary tract (64.97%) was the most common cause of liver abscess. Multiple abscesses, mixed organisms and abscess complications are all associated with a significantly increased mortality. However, the lethality of the primary disease process was the most important factor in determining survival.CONCLUSION: Transperitoneal surgical drainage and antibiotics are the mainstay of treatment. Percutaneous drainage is recommended for high risk patients only.
文摘The adsorption capacity of activated carbon produced from oil palm empty fruit bunches through removal of 2,4-dichlorophenol from aqueous solution was carried out in the laboratory. The activated carbon was produced by thermal activation of activation time with 30 min at 800℃. The adsorption process conditions were determined with the statistical optimization followed by central composite design. A developed polynomial model for operating conditions of adsorption process indicated that the optimum conditions for maximum adsorption of phenolic compound were: agitation rate of 100 r/min, contact time of 8 h, initial adsorbate concentration of 250 mg/L and pH 4. Adsorption isotherms were conducted to evaluate biosorption process. Langmuir isotherm was more favorable (R^2=0.93) for removal of 2,4-dichlorophenol by the activated carbon rather than Freundlich isotherm (R^2=0.88).
文摘In this article, a novel (G'/G)-expansion method is proposed to search for the traveling wave solutions of nonlinear evolution equations. We construct abundant traveling wave solutions involving parameters to the Boussinesq equation by means of the suggested method. The performance of the method is reliable and useful, and gives more general exact solutions than the existing methods. The new (G'/G)-expansion method provides not only more general forms of solutions but also cuspon, peakon, soliton, and periodic waves.
文摘Postoperative sleep disturbance is a common occurrence with significant adverse effects on patients including delayed recovery,impairment of cognitive function,pain sensitivity and cardiovascular events.The development of postoperative sleep disturbance is multifactorial and involves the surgical inflammatory response,the severity of surgical trauma,pain,anxiety,the use of anesthetics and environmental factors such as nocturnal noise and light levels.Many of these factors can be managed perioperatively to minimize the deleterious impact on sleep.Pharmacological and non-pharmacological treatment strategies for postoperative sleep disturbance include dexmedetomidine,zolpidem,melatonin,enhanced recovery after surgery(ERAS) protocol and controlling of environmental noise and light levels.It is likely that a combination of pharmacological and non-pharmacological therapies will have the greatest impact;however,further research is required before their use can be routinely recommended.
基金the Pakistan Science Foundation(PSF)for providing financial support for the study
文摘A comprehensive landslide inventory and susceptibility maps are prerequisite for developing and implementing landslide mitigation strategies. Landslide susceptibility maps for the landslides prone regions in northern Pakistan are rarely available. The Hunza-Nagar valley in northern Pakistan is known for its frequent and devastating landslides. In this paper, we have developed a landslide inventory map for Hunza-Nagar valley by using the visual interpretation of the SPOT-5 satellite imagery and mapped a total of 172 landslides. The landslide inventory was subsequently divided into modelling and validation data sets. For the development of landslide susceptibility map seven discrete landslide causative factors were correlated with the landslide inventory map using weight of evidence and frequency ratio statistical models. Four different models of conditional independence were used for the selection of landslide causative factors. The produced landslides susceptibility maps were validated by the success rate and area under curves criteria. The prediction power of the models was also validated with the prediction rate curve. The validation results shows that the success rate curves of the weight of evidence and the frequency models are 82% and 79%, respectively. The prediction accuracy results obtained from this study are 84% for weight of evidence model and 80% for the frequency ratio model. Finally, the landslide susceptibility index maps were classified into five different varying susceptibility zones. The validation and prediction result indicates that the weight of evidence and frequency ratio model are reliable to produce an accurate landslide susceptibility map, which may be helpful for landslides management strategies.
文摘 AIM: To explore the prevalence and risk factors for nonalcoholic steatohepatitis (NASH) in nonalcoholic fatty liver disease (NAFLD) patients. METHODS: We have included 493 patients with sonographic evidence of a fatty change, and 177 of these individuals were evaluated and confirmed after liver biopsy. The exclusion criteria consisted of significant alcohol abuse (【 20 g daily), evidence of hepatitis B and C, evidence of drug-induced fatty liver disease and other specific liver diseases such as hemochromatosis, Wilson’s disease or autoimmune liver disease. The patients were assessed for metabolic syndrome, and biochemical, anthropometric and histopathological evaluations were carried out. The degree of disease activity in the NAFLD patients was evaluated using the NAFLD Activity Score. The data were analyzed by SPSS, version 16.0. RESULTS: Females predominated among the study participants (250, 57.0%), and the mean age was 40.8 ± 10.2 years. The numbers of overweight, obeseⅠ and obese Ⅱ patients were 58 (13.2%), 237 (53.9%) and 93 (21.2%), respectively. However, there were 422 (96.2%) centrally obese patients. NASH was absent in 10 (5.6%) cases, borderline in 92 (52.6%) cases and present in 75 (42.4%) cases. The presence of diabetes could significantly (P = 0.001) differentiate NASH from simple steatosis. The following parameters did not influence the development of NASH: age, sex, basal metabolic index, waist circumference, serum high-density lipoprotein, triglyceride, insulin resistance index, hypertension and metabolic syndrome. The serum gammaglutamyl transpeptidase (GGT) level was significantly higher (P = 0.05, 51.7 ± 32.8 and 40.4 ± 22.6 U/L) in the NASH patients, with a sensitivity of 45% and a specificity of only 68%. The serum alanine aminotransferase and aspartate aminotransferase levels were not able to predict NASH. CONCLUSION: Females were the predominant sufferers of NAFLD in Bangladesh. The prevalence of NASH was high. Diabetes was found to be the main culprit in developing NASH. GGT
基金This work was supported by SUG Research Grant M4082126.050 by the School of Mechanical and Aerospace Engineering(MAE),Nanyang Technological University(NTU),SingaporeNTU-CAAS Research Grant M4062429.052 by the ATM Research Institute,School of MAE,NTU,Singapore.
文摘Intractable delays occur in air traffic due to the imbalance between ever-increasing air traffic demand and limited airspace capacity.As air traffic is associated with complex air transport systems,delays can be magnified and propagated throughout these systems,resulting in the emergent behavior known as delay propagation.An understanding of delay propagation dynamics is pertinent to modern air traffic management.In this work,we present a complex network perspective of delay propagation dynamics.Specifically,we model air traffic scenarios using spatial–temporal networks with airports as the nodes.To establish the dynamic edges between the nodes,we develop a delay propagation method and apply it to a given set of air traffic schedules.Based on the constructed spatial-temporal networks,we suggest three metrics-magnitude,severity,and speed-to gauge delay propagation dynamics.To validate the effectiveness of the proposed method,we carry out case studies on domestic flights in the Southeastern Asia region(SAR)and the United States.Experiments demonstrate that the propagation magnitude in terms of the number of flights affected by delay propagation and the amount of propagated delays for the US traffic are respectively five and ten times those of the SAR.Experiments further reveal that the propagation speed for US traffic is eight times faster than that of the SAR.The delay propagation dynamics reveal that about six hub airports in the SAR have significant propagated delays,while the situation in the United States is considerably worse,with a corresponding number of around 16.This work provides a potent tool for tracing the evolution of air traffic delays.
文摘Clinacanthus nutans Lindau is known as snake grass belonging to the Acanlhaceae family.This plant has diverse and potential medicinal uses in traditional herbal medicine for treating skin rashes,insects and snake bites,lesions caused by herpes simplex virus,diabetes,and gout in Malaysia.Indonesia.Thailand and China.Phylochemieal investigations documented the varied contents of bioaclive compounds from litis plant namely flavonoids,glycosides,glycoglyeerolipids.cerebrosides and monoacylmonogalatosylglycerol.The pharmacological experiment proved that various types of extracts and pure compounds from this species exhibited a broad range of biological properties such as anti-inflammatory,antiviral,antioxidant,and anti-diabetic activities.The lindings of toxicity study showed that extracts from this plant did not show any toxicity thus it can be used as strong therapeutic agents for specific diseased conditions.However,further experiments on chemical components and their mode of action showing biological activities are required to elucidate the complete phytochemical profile and assess to confirm their suitability tor future drugs.This review summarizes the medicinal uses,phytochemistry and pharmacology of this plant in order to explore its therapeutic potential and gaps necessitating for prospected research work.
基金Supported by a grant from Ministry of Science and Technology,Bangladesh(No.BPROM/SHA-9/B-ANI-PRO/2009/324)
文摘Objective:To investigate mosquitocidal effects of ethanolic extract of(lowers of Tagetes erecta(T.erecta) and its chloroform and petroleum ether soluble fractions against the larvae of Culex quinquefasciatus(Cx.quinquefasciatus).Methods:The fresh flowers of T.erecta were extracted in cold with ethanol(5.0 L) and after concentration,the ethanol extract was fractionated with chloroform and petroleum ether to afford a brownish syrupy suspension of ethanol extract(50.0 g),petroleum ether soluble fraction(18.6 g) and chloroform soluble fraction(23.8 g).The larvicidal effect of ethanol extract and their solvent fractions were determined by the standard procedure of WHO against different instars of Cx.quinquefasciatus.Results:Among the tested samples the chloroform soluble fractions showed the highest toxicity and consequently,the lowest LC_(50) values(14.14 μ g/mL,17.06 μ g/mL.36.88 μ g/mL and 75.48 μ g/mL) for all the instars larvae of Cx.quinquefasciatus.The larvae showed comparative tolerance in the course of increasing age and time.Conclusions:It can be concluded that the flowers of T.erecta are very effective natural larvicide and could be useful against Cx.quinquefasciatus.