Low-salinity water injection has been utilized as a promising method for oil recovery in recent years. Low-salinity water flooding changes the ion composition or brine salinity for improving oil recovery. Recently, th...Low-salinity water injection has been utilized as a promising method for oil recovery in recent years. Low-salinity water flooding changes the ion composition or brine salinity for improving oil recovery. Recently, the application of nanoparticles with low-salinity water flooding has shown remarkable results in enhanced oil recovery(EOR). Many studies have been performed on the effect of nanofluids on EOR mechanisms. Their results showed that nanofluids can improve oil recovery when used in low-salinity water flooding. In this work, the effects of injection of low-salinity water and low-salinity nanofluid(prepared by adding SiO_2 nanoparticles to low-salinity water) on oil recovery were investigated. At first, the effects of ions were investigated with equal concentrations in low-salinity water flooding. The experimental results showed that the monovalent ions had better performance than the divalent ions because of them having more negative zeta potential and less ionic strength. Also, low-salinity water flooding recovered 6.1% original oil in place(OOIP) more than the high-salinity flooding. Contact angle measurements demonstrated that low-salinity water could reduce the contact angle between oil and water. Then in the second stage, experiments were continued by adding SiO_2 nanoparticles to the K+ solution which had the highest oil recovery at the first stage. The experimental results illustrated that the addition of Si02 nanoparticles up to 0.05 wt% increased oil recovery by about 4% OOIP more than the low-salinity water flooding.展开更多
High-entropy alloys(HEAs)are suitable for engineering applications requiring excellent mechanical,corrosion,thermal,and magnetic properties.In the last decade,electrodeposition has emerged as a promising synthesis tec...High-entropy alloys(HEAs)are suitable for engineering applications requiring excellent mechanical,corrosion,thermal,and magnetic properties.In the last decade,electrodeposition has emerged as a promising synthesis technique for HEAs.Research has focused on the influence of procedure parameters on the deposition of different HEA layers and the effect of their microstructure on their corrosion and magnetic properties.This review of current literature provides comprehensive information on HEAs and the use of direct and pulse electrodeposition as a synthesis technique for these materials.This review also addresses the research gaps on HEA production via electrodeposition,such as using other ceramic particles instead of graphene oxide in composite structures based on HEAs.展开更多
A full-scale, two-story, two-by-one bay, steel braced-frame was subjected to a number of unidirectional ground motions using three shake tables at the UNR-NEES site. The test-bed frame was designed to study the seismi...A full-scale, two-story, two-by-one bay, steel braced-frame was subjected to a number of unidirectional ground motions using three shake tables at the UNR-NEES site. The test-bed frame was designed to study the seismic performance of nonstructural systems including steel-framed gypsum partition walls, suspended ceilings and fire sprinkler systems. The frame can be configured to perform as an elastic or inelastic system to generate large floor accelerations or large inter story drift, respectively. In this study, the dynamic performance of the linear and nonlinear test-beds was comprehensively studied. The seismic performance of nonstructural systems installed in the linear and nonlinear test-beds were assessed during extreme excitations. In addition, the dynamic interactions of the test-bed and installed nonstructural systems are investigated.展开更多
Heparin is a negatively charged polysaccharide with various chain lengths and a hydrophilic backbone.Due to its fascinating chemical and physical properties,nontoxicity,biocompatibility,and biodegradability,heparin ha...Heparin is a negatively charged polysaccharide with various chain lengths and a hydrophilic backbone.Due to its fascinating chemical and physical properties,nontoxicity,biocompatibility,and biodegradability,heparin has been extensively used in different fields of medicine,such as cardiovascular and hematology.This review highlights recent and future advancements in designing materials based on heparin for various biomedical applications.The physicochemical and mechanical properties,biocompatibility,toxicity,and biodegradability of heparin are discussed.In addition,the applications of heparin-based materials in various biomedical fields,such as drug/gene delivery,tissue engineering,cancer therapy,and biosensors,are reviewed.Finally,challenges,opportunities,and future perspectives in preparing heparin-based materials are summarized.展开更多
Recently,renewable energy resources and their impacts have sparked a heated debate to resolve the Australian energy crisis.There are many projects launched throughout the country to improve network security and reliab...Recently,renewable energy resources and their impacts have sparked a heated debate to resolve the Australian energy crisis.There are many projects launched throughout the country to improve network security and reliability.This paper aims to review the current status of different renewable energy resources along with their impacts on society and the environment.Besides,it provides for the first time the statistics of the documents published in the field of renewable energy in Australia.The statistics include information such as the rate of papers published,possible journals for finding relative paper,types of documents published,top authors,and the most prevalent keywords in the field of renewable energy in Australia.It will focus on solar,wind,biomass,geothermal and hydropower technologies and will investigate the social and environmental impacts of these technologies.展开更多
Gas-water-rock interactions during natural gas storage in a low permeability aquifer and main factors affecting the storage capacity were investigated in laboratory with core experiments. The results showed that gas i...Gas-water-rock interactions during natural gas storage in a low permeability aquifer and main factors affecting the storage capacity were investigated in laboratory with core experiments. The results showed that gas injection flow rate had a major impact on stored gas volume and stored gas volume is higher at high flow rate. Gas storage volume ranged between 6%-20% of the pore space at experimental condition. Enhancing injection pressure can enhance gas storage volume. Statistics showed that injection flow rate had a greater influence on the gas storage volume than pressure. The retention time also had an impact on the gas storage process. Most of the natural gas was trapped in the reservoir and could not be produced after long time of retention. Atomic absorption spectroscopy indicated that ions concentrations of the brine and water evaporation increased when gas was injected into brine saturated core, and precipitation might occur, reducing porosity and permeability of core. Gas chromatography analysis showed that the concentration of carbon dioxide in the natural gas decreased and the concentration of methane increased after storage in the core.展开更多
Regeneration of craniofacial bone defects is a key issue in the bone regeneration field.Hence,novel treatment strategies,such as tissue engineering using porous scaffolds,have been developed.An ideal tissue-engineered...Regeneration of craniofacial bone defects is a key issue in the bone regeneration field.Hence,novel treatment strategies,such as tissue engineering using porous scaffolds,have been developed.An ideal tissue-engineered scaffold for bone tissue regeneration should possess pores to facilitate nutrients transmission and support repar-ative tissue ingrowth,bioactivity for osteoconduction and osseointegration,and biocompatibility to improve cell attachment,proliferation,and extracellular matrix formation.In the present study,we manufactured chitosan-based hydrogels substituted with alginate with optimized properties by extrusion-based three-dimensional(3D)printing.3D printing of the scaffolds enables the designing and developing of complex architectures for cranio-facial reconstruction using computer-aided design(CAD).Different ratios(2.5,5,and 10%)of hydroxyapatite were added to the hydrogel,printed,and subsequently lyophilized to augment the physical and biological char-acteristics of the scaffolds.Hydroxyapatite incorporation into the chitosan-based scaffolds increased the porosity and pore size of the printed scaffolds.In addition,the presence of hydroxyapatite amplified apatite formation and decreased the size of formed apatite crystals.All the scaffold samples showed biocompatible properties and did not have toxicity toward rat bone marrow mesenchymal stem cells.Furthermore,the scaffolds containing 5%w/w hydroxyapatite exhibited significant growth in cell viability compared to the control.Overall,it is concluded that chitosan-based scaffolds adorned with hydroxyapatite are considerable for regenerating craniofacial bone defects.展开更多
The objective of this review is the determination of tyramine in 13 nonalcoholic beers (Maoshaieer) of Tehran market and survey of it’s probably interaction with monoamine oxidase inhibitor drugs (MAOIs) has been inv...The objective of this review is the determination of tyramine in 13 nonalcoholic beers (Maoshaieer) of Tehran market and survey of it’s probably interaction with monoamine oxidase inhibitor drugs (MAOIs) has been investigated. Tyramine was at the highest levels in Baltika (111.34 ± 8.19 μg/ml) and at the lowest level in Bitmalt (8.01 ± 2.09 μg/ml). Comparing different flavors of malt drinks, the highest tyramine content was shown for classic or normal flavor (average 72.99 ± 30.87 μg/ml), while the lowest value belonged to cantaloupe flavored drinks (average 10.55 ± 1.29 μg/ml). In our study, it is seen that there is a significant difference between import and Iranian non-alcoholic beers, the import ones has more tyramine than Iranians. A number of 10 kinds of 13 samples interact whit MAOIs in one serving (250 ml) usage 18.50 mg. The highest tyramine content of Iranian ones is 17.74 mg/250ml and for import ones is 27.83 mg/250ml.展开更多
Biodegradable and absorptive wound dresses with antibacterial activity are in demand to accelerate wound heal-ing along with eliminating bacterial infection.Plant-derived naphthoquinones compounds such as lawsone have...Biodegradable and absorptive wound dresses with antibacterial activity are in demand to accelerate wound heal-ing along with eliminating bacterial infection.Plant-derived naphthoquinones compounds such as lawsone have shown sustained antibacterial functions to avoid development of bacterial resistance by reducing pH or attaching to bacterial proteins.Here the nanofibrous mats based on chitosan/polyethylene oxide(PEO)fibers containing various concentrations of lawsone(0,1,3,7,10%wt.)were fabricated by electrospinning for potential applications as wound dressing materials.The results exhibited that the chitosan/PEO/Lawsone nanofibers possess antibacterial activity toward Gram-negative and-positive bacteria.Surprisingly,the addition of lawsone in the proper amount into chitosan/PEO nanofibers not only introduced an antithetical property but also reduced the platform’s cytotoxicity,promoting cell viability of normal human fibroblast cells.Accordingly,the achieved data suggest the potential application of biocompatible nanofibrous mats as an antibacterial wound dressing material.展开更多
In the present study,modified Ibarra,Medina and Krawinkler moment-rotation parameters are used for modeling the uncertainties in concrete moment frame structures.Correlations of model parameters in a component and bet...In the present study,modified Ibarra,Medina and Krawinkler moment-rotation parameters are used for modeling the uncertainties in concrete moment frame structures.Correlations of model parameters in a component and between two structural components were considered to analyze these uncertainties.In the first step,the structural collapse responses were obtained by producing 281 samples for the uncertainties using the Latin hypercube sampling(LHS)method,considering the probability distribution of the uncertainties and performing incremental dynamic analyses.In the second step,281 new samples were produced for the uncertainties by the central composite design(CCD)method without considering the probability distribution of the uncertainties and calculating the structural collapse responses.Then,using the response surface method(RSM)and artificial neural network(ANN)for the two simulation modes,structural collapse responses were predicted.The results indicated that the collapse responses at levels of 0 to 100%obtained from the two simulations have a high correlation coefficient of 98%.This suggests that random variables can be simulated without considering the probability distribution of uncertainties,by performing uncertainty analysis to determine structural collapse responses.展开更多
The utilization of biomarkers for in vivo and in vitro research is growing rapidly. This is mainly due to the enormous potential of biomarkers in evaluating molecular and cellular abnormalities in cell models and in t...The utilization of biomarkers for in vivo and in vitro research is growing rapidly. This is mainly due to the enormous potential of biomarkers in evaluating molecular and cellular abnormalities in cell models and in tissue, and evaluating drug responses and the effectiveness of therapeutic intervention strategies. An important way to analyze the development of the human body is to assess molecular markers in embryonic specialized cells, which include the ectoderm, mesoderm, and endoderm. Neuronal development is controlled through the gene networks in the neural crest and neural tube, both components of the ectoderm. The neural crest differentiates into several different tissues including, but not limited to, the peripheral nervous system, enteric nervous system, melanocyte, and the dental pulp. The neural tube eventually converts to the central nervous system. This review provides an overview of the differentiation of the ectoderm to a fully functioning nervous system, focusing on molecular biomarkers that emerge at each stage of the cellular specialization from multipotent stem cells to completely differentiated cells. Particularly, the otic placode is the origin of most of the inner ear cell types such as neurons, sensory hair cells, and supporting cells. During the development, different auditory cell types can be distinguished by the expression of the neurogenin differentiation factor1 (Neuro D1), Brn3a, and transcription factor GATA3. However, the mature auditory neurons express other markers including bIII tubulin, the vesicular glutamate transporter (VGLUT1), the tyrosine receptor kinase B and C (Trk B, C), BDNF, neurotrophin 3 (NT3), Calretinin, etc.展开更多
Asphalt mow strips are typically used as vegetation barriers around guardrail posts in the design of roadside safety structures. Asphalt mow strips have historically been modeled as a rigid layer in simulations;this a...Asphalt mow strips are typically used as vegetation barriers around guardrail posts in the design of roadside safety structures. Asphalt mow strips have historically been modeled as a rigid layer in simulations;this assumption results in significant ground level restraint on the guardrail post. However, experiments have shown that asphalt rupture should be considered in the analysis of the response of guardrail posts embedded in mow strips. The present study investigates the effect of asphalt material properties and mow strip geometry on guardrail post performance using finite element simulations. Numerical simulations are performed and correlated with results from static experiments and material testing. The test simulations and experimental results are used to evaluate the response of guardrail posts with various mow strip designs to predict the level of restraint from the asphalt layer. The model is then used to investigate the effects of asphalt material properties and mow strip geometry on the overall performance of the system. The results demonstrate that including asphalt rupture in numerical simulations is essential in accurately predicting the behavior of guardrail posts installed in asphalt mow strips. In addition, mow strip geometry along with asphalt material properties significantly affect the guardrail post response.展开更多
AIM: To quantify the exposure levels and to assess pulmonary reactions associated with exposure to cotton dust and its biological contaminants.METHODS: All employees(51 male workers) of a ginning industry as well as 5...AIM: To quantify the exposure levels and to assess pulmonary reactions associated with exposure to cotton dust and its biological contaminants.METHODS: All employees(51 male workers) of a ginning industry as well as 51 referent unexposed subjects from clerical staff of an educational center were investigated. Atmospheric concentrations of cotton dust and bioaerosols were measured. Furthermore, bacterial and fungal genera and species were identified by an expert microbiologist and an experienced mycologist. A standard respiratory symptom questionnaire was filled out for the subjects and they underwent multiple spirometry tests, at the beginning and at the end of work season as well as prior to(pre-exposure base line values) and at end of the first shift of workweek(post exposure). RESULTS: Gram negative bacteria including Enterobacter agglomerans and Pseudomonas spp. were found to be the dominant bacterial species and genera, respectively. Similarly, dominant fungi were identified tobe Mucor sp. Rhizopus sp. and Aspergillus niger. Mean atmospheric concentrations of cotton dust in ginning and outdoor areas were found to be 35.2 and 6.8 mg/m3, respectively. The prevalence rates of cough, phlegm, wheezing, dyspenea and grade 1/2 byssinosis among the exposed subjects were significantly higher than their corresponding values for the unexposed employees(P < 0.05). Additionally, significant differences were noted in the mean baseline value(preshift) of vital capacity, forced expiratory volume in the first second(FEV1)and FEV1/forced vital capacity ratio of the exposed subjects when compared with those of their referent counterparts. Similarly, significant cross shift decrements were noted in most parameters of pulmonary function of the exposed subjects.CONCLUSION: Seasonal exposure to cotton dust induces both acute, partially reversible, and chronic irreversible decrements in the lungs' functional capacities as well as increased prevalence of respiratory symptoms.展开更多
Background: CHF (Congestive Heart Failure) is one of the most important causes of mortality and morbidity in the world. Diuretics such as spironolactone can decrease pulmonary congestion and reduce the amount of fibro...Background: CHF (Congestive Heart Failure) is one of the most important causes of mortality and morbidity in the world. Diuretics such as spironolactone can decrease pulmonary congestion and reduce the amount of fibrosis in CHF patients. The goal was to assess whether spironolactone can decrease air way resistance and can we follow up the effect of diuretic therapy in patients of heart failure quantitatively by means of impulse oscillometry. Methods: It was clinical trial which performed in Ahvaz teaching hospital. 24 patients with congestive heart failure (CHF) which was classified as functional class II-IV and had EF Result: The age of patient was 61 ± 10 and the age of control was 57 ± 7 years old. The data of oscillometry before and after spironolactone were X5 (−0.14 ± 0.05 vs −0.14 ± 0.05, P: 0.93), R5 (0.39 ± 0.21 vs 0.39 ± 0.15, P: 0.35), X20 (−0.04 ± 0.06 vs −0.06 ± 0.06, P: 0.37), R20 (0.04 ± 0.03 vs 0.06 ± 0.06, P: 0.37), Zrs (0.39 ± 0.21 vs 0.39 ± 0.15, P: 0.35). Conclusion: There was a trend toward reduction of peripheral airway resistances in CHF patients than controls with use of 1 month of spironolactone. Although there was not significant change in the number of X5, R5, X20, R20 occurred the trend toward reduction of number triggers the point that oscillometry can be used for quantitative follow up of CHF patients.展开更多
The elimination of the silica matrix of composites by HF occurred by a two-step reaction deposition of a Cs2.5H0.5PW12O40(CsHPW) salt nanocrystal.We used 2D hexagonal SBA-15 silica as a template for the nanofabricatio...The elimination of the silica matrix of composites by HF occurred by a two-step reaction deposition of a Cs2.5H0.5PW12O40(CsHPW) salt nanocrystal.We used 2D hexagonal SBA-15 silica as a template for the nanofabrication of CsHPW nanoparticles.Nanocast CsHPW materials are stable against leaching and colloidization in polar solvents.The catalytic performance of the nanocast CsHPW materi-als exceeded that of bulk Cs2.5H0.5PW12O40,which is the most active among the acidic HPW salts.A series of novel 1,3,5-triaryl-pyrazoline derivatives were synthesized by the reaction between chalcone and phenylhydrazine in high yield in the presence of CsHPW salt nanocrystals.展开更多
Since its first release in 2008,Norine remains the unique resource completely devoted to nonribosomal peptides(NRPs).They are very attractive microbial secondary metabolites,displaying a remarkable diversity of struct...Since its first release in 2008,Norine remains the unique resource completely devoted to nonribosomal peptides(NRPs).They are very attractive microbial secondary metabolites,displaying a remarkable diversity of structure and functions.Norine(http://bioinfo.lifl.fr/NRP)includes a database now containing more than 1160 annotated peptides and user-friendly interfaces enabling the querying of the database,through the annotations or the structure of the peptides.Dedicated tools are associated for structural comparison of the compounds and prediction of their biological activities.In this paper,we start by describing the knowledgebase and the dedicated tools.We then present some user cases to show how useful Norine is for the discovery of novel nonribosomal peptides.展开更多
BACKGROUND AND OBJECTIVE Coccydynia can lead to significant functional disability and worsening of quality of life if not properly managed. In this study, we aim to assess the outcomes of extracorporeal shock wave the...BACKGROUND AND OBJECTIVE Coccydynia can lead to significant functional disability and worsening of quality of life if not properly managed. In this study, we aim to assess the outcomes of extracorporeal shock wave therapy in patients with coccydynia. METHODS A prospective case series study was carried out from January to December 2015. Twenty-three patients, mean age of 38.3±12.1 (range 18-64), were included. The majority were females (13;56.5%), had pain for at least 6 weeks (17;73.9%) and had trauma to the sacrococcygeal region (17;73.9%). They had three sessions (one session per week for three consecutive weeks) of focused shock wave therapy directed to the maximal point of coccygeal tenderness. Numerical pain scale and Oswestry disability index were used to assess outcome. RESULTS Six (26.1%) patients did not complete the follow-up because of no, or minimal, improvement of their pain. After 6 months of follow-up, the median numerical pain scale significantly decreased from 7.0±4.0 to 2.0±2.0 among the 17 patients with coccydynia (P<0.001). The median Oswestry disability index improved from 24.0±9.0 before therapy to 8.0±9.0 at final follow-up (P<0.001). Before treatment, 12 (70.6%) patients had moderate-to-severe disability. In contrast, no patients had severe disability and only one (5.9%) patient had moderate disability at final follow-up (P<0.001). CONCLUSION Extracorporeal shock wave therapy had favorable outcomes in treating coccydynia. The majority of patients had partial relief of their pain and disability following this therapy.展开更多
文摘Low-salinity water injection has been utilized as a promising method for oil recovery in recent years. Low-salinity water flooding changes the ion composition or brine salinity for improving oil recovery. Recently, the application of nanoparticles with low-salinity water flooding has shown remarkable results in enhanced oil recovery(EOR). Many studies have been performed on the effect of nanofluids on EOR mechanisms. Their results showed that nanofluids can improve oil recovery when used in low-salinity water flooding. In this work, the effects of injection of low-salinity water and low-salinity nanofluid(prepared by adding SiO_2 nanoparticles to low-salinity water) on oil recovery were investigated. At first, the effects of ions were investigated with equal concentrations in low-salinity water flooding. The experimental results showed that the monovalent ions had better performance than the divalent ions because of them having more negative zeta potential and less ionic strength. Also, low-salinity water flooding recovered 6.1% original oil in place(OOIP) more than the high-salinity flooding. Contact angle measurements demonstrated that low-salinity water could reduce the contact angle between oil and water. Then in the second stage, experiments were continued by adding SiO_2 nanoparticles to the K+ solution which had the highest oil recovery at the first stage. The experimental results illustrated that the addition of Si02 nanoparticles up to 0.05 wt% increased oil recovery by about 4% OOIP more than the low-salinity water flooding.
文摘High-entropy alloys(HEAs)are suitable for engineering applications requiring excellent mechanical,corrosion,thermal,and magnetic properties.In the last decade,electrodeposition has emerged as a promising synthesis technique for HEAs.Research has focused on the influence of procedure parameters on the deposition of different HEA layers and the effect of their microstructure on their corrosion and magnetic properties.This review of current literature provides comprehensive information on HEAs and the use of direct and pulse electrodeposition as a synthesis technique for these materials.This review also addresses the research gaps on HEA production via electrodeposition,such as using other ceramic particles instead of graphene oxide in composite structures based on HEAs.
基金National Science Foundation under Grant No.0721399
文摘A full-scale, two-story, two-by-one bay, steel braced-frame was subjected to a number of unidirectional ground motions using three shake tables at the UNR-NEES site. The test-bed frame was designed to study the seismic performance of nonstructural systems including steel-framed gypsum partition walls, suspended ceilings and fire sprinkler systems. The frame can be configured to perform as an elastic or inelastic system to generate large floor accelerations or large inter story drift, respectively. In this study, the dynamic performance of the linear and nonlinear test-beds was comprehensively studied. The seismic performance of nonstructural systems installed in the linear and nonlinear test-beds were assessed during extreme excitations. In addition, the dynamic interactions of the test-bed and installed nonstructural systems are investigated.
基金funding from the National Institutes of Health(4UG3TR003148-02,and 5R01AR073135-06)the Terasaki Institute for Biomedical Innovation.
文摘Heparin is a negatively charged polysaccharide with various chain lengths and a hydrophilic backbone.Due to its fascinating chemical and physical properties,nontoxicity,biocompatibility,and biodegradability,heparin has been extensively used in different fields of medicine,such as cardiovascular and hematology.This review highlights recent and future advancements in designing materials based on heparin for various biomedical applications.The physicochemical and mechanical properties,biocompatibility,toxicity,and biodegradability of heparin are discussed.In addition,the applications of heparin-based materials in various biomedical fields,such as drug/gene delivery,tissue engineering,cancer therapy,and biosensors,are reviewed.Finally,challenges,opportunities,and future perspectives in preparing heparin-based materials are summarized.
文摘Recently,renewable energy resources and their impacts have sparked a heated debate to resolve the Australian energy crisis.There are many projects launched throughout the country to improve network security and reliability.This paper aims to review the current status of different renewable energy resources along with their impacts on society and the environment.Besides,it provides for the first time the statistics of the documents published in the field of renewable energy in Australia.The statistics include information such as the rate of papers published,possible journals for finding relative paper,types of documents published,top authors,and the most prevalent keywords in the field of renewable energy in Australia.It will focus on solar,wind,biomass,geothermal and hydropower technologies and will investigate the social and environmental impacts of these technologies.
文摘Gas-water-rock interactions during natural gas storage in a low permeability aquifer and main factors affecting the storage capacity were investigated in laboratory with core experiments. The results showed that gas injection flow rate had a major impact on stored gas volume and stored gas volume is higher at high flow rate. Gas storage volume ranged between 6%-20% of the pore space at experimental condition. Enhancing injection pressure can enhance gas storage volume. Statistics showed that injection flow rate had a greater influence on the gas storage volume than pressure. The retention time also had an impact on the gas storage process. Most of the natural gas was trapped in the reservoir and could not be produced after long time of retention. Atomic absorption spectroscopy indicated that ions concentrations of the brine and water evaporation increased when gas was injected into brine saturated core, and precipitation might occur, reducing porosity and permeability of core. Gas chromatography analysis showed that the concentration of carbon dioxide in the natural gas decreased and the concentration of methane increased after storage in the core.
文摘Regeneration of craniofacial bone defects is a key issue in the bone regeneration field.Hence,novel treatment strategies,such as tissue engineering using porous scaffolds,have been developed.An ideal tissue-engineered scaffold for bone tissue regeneration should possess pores to facilitate nutrients transmission and support repar-ative tissue ingrowth,bioactivity for osteoconduction and osseointegration,and biocompatibility to improve cell attachment,proliferation,and extracellular matrix formation.In the present study,we manufactured chitosan-based hydrogels substituted with alginate with optimized properties by extrusion-based three-dimensional(3D)printing.3D printing of the scaffolds enables the designing and developing of complex architectures for cranio-facial reconstruction using computer-aided design(CAD).Different ratios(2.5,5,and 10%)of hydroxyapatite were added to the hydrogel,printed,and subsequently lyophilized to augment the physical and biological char-acteristics of the scaffolds.Hydroxyapatite incorporation into the chitosan-based scaffolds increased the porosity and pore size of the printed scaffolds.In addition,the presence of hydroxyapatite amplified apatite formation and decreased the size of formed apatite crystals.All the scaffold samples showed biocompatible properties and did not have toxicity toward rat bone marrow mesenchymal stem cells.Furthermore,the scaffolds containing 5%w/w hydroxyapatite exhibited significant growth in cell viability compared to the control.Overall,it is concluded that chitosan-based scaffolds adorned with hydroxyapatite are considerable for regenerating craniofacial bone defects.
文摘The objective of this review is the determination of tyramine in 13 nonalcoholic beers (Maoshaieer) of Tehran market and survey of it’s probably interaction with monoamine oxidase inhibitor drugs (MAOIs) has been investigated. Tyramine was at the highest levels in Baltika (111.34 ± 8.19 μg/ml) and at the lowest level in Bitmalt (8.01 ± 2.09 μg/ml). Comparing different flavors of malt drinks, the highest tyramine content was shown for classic or normal flavor (average 72.99 ± 30.87 μg/ml), while the lowest value belonged to cantaloupe flavored drinks (average 10.55 ± 1.29 μg/ml). In our study, it is seen that there is a significant difference between import and Iranian non-alcoholic beers, the import ones has more tyramine than Iranians. A number of 10 kinds of 13 samples interact whit MAOIs in one serving (250 ml) usage 18.50 mg. The highest tyramine content of Iranian ones is 17.74 mg/250ml and for import ones is 27.83 mg/250ml.
基金supported by the Research and Technology Deputy of the Hamadan University of Medical Sciences(Grant number 9902231097).
文摘Biodegradable and absorptive wound dresses with antibacterial activity are in demand to accelerate wound heal-ing along with eliminating bacterial infection.Plant-derived naphthoquinones compounds such as lawsone have shown sustained antibacterial functions to avoid development of bacterial resistance by reducing pH or attaching to bacterial proteins.Here the nanofibrous mats based on chitosan/polyethylene oxide(PEO)fibers containing various concentrations of lawsone(0,1,3,7,10%wt.)were fabricated by electrospinning for potential applications as wound dressing materials.The results exhibited that the chitosan/PEO/Lawsone nanofibers possess antibacterial activity toward Gram-negative and-positive bacteria.Surprisingly,the addition of lawsone in the proper amount into chitosan/PEO nanofibers not only introduced an antithetical property but also reduced the platform’s cytotoxicity,promoting cell viability of normal human fibroblast cells.Accordingly,the achieved data suggest the potential application of biocompatible nanofibrous mats as an antibacterial wound dressing material.
文摘In the present study,modified Ibarra,Medina and Krawinkler moment-rotation parameters are used for modeling the uncertainties in concrete moment frame structures.Correlations of model parameters in a component and between two structural components were considered to analyze these uncertainties.In the first step,the structural collapse responses were obtained by producing 281 samples for the uncertainties using the Latin hypercube sampling(LHS)method,considering the probability distribution of the uncertainties and performing incremental dynamic analyses.In the second step,281 new samples were produced for the uncertainties by the central composite design(CCD)method without considering the probability distribution of the uncertainties and calculating the structural collapse responses.Then,using the response surface method(RSM)and artificial neural network(ANN)for the two simulation modes,structural collapse responses were predicted.The results indicated that the collapse responses at levels of 0 to 100%obtained from the two simulations have a high correlation coefficient of 98%.This suggests that random variables can be simulated without considering the probability distribution of uncertainties,by performing uncertainty analysis to determine structural collapse responses.
文摘The utilization of biomarkers for in vivo and in vitro research is growing rapidly. This is mainly due to the enormous potential of biomarkers in evaluating molecular and cellular abnormalities in cell models and in tissue, and evaluating drug responses and the effectiveness of therapeutic intervention strategies. An important way to analyze the development of the human body is to assess molecular markers in embryonic specialized cells, which include the ectoderm, mesoderm, and endoderm. Neuronal development is controlled through the gene networks in the neural crest and neural tube, both components of the ectoderm. The neural crest differentiates into several different tissues including, but not limited to, the peripheral nervous system, enteric nervous system, melanocyte, and the dental pulp. The neural tube eventually converts to the central nervous system. This review provides an overview of the differentiation of the ectoderm to a fully functioning nervous system, focusing on molecular biomarkers that emerge at each stage of the cellular specialization from multipotent stem cells to completely differentiated cells. Particularly, the otic placode is the origin of most of the inner ear cell types such as neurons, sensory hair cells, and supporting cells. During the development, different auditory cell types can be distinguished by the expression of the neurogenin differentiation factor1 (Neuro D1), Brn3a, and transcription factor GATA3. However, the mature auditory neurons express other markers including bIII tubulin, the vesicular glutamate transporter (VGLUT1), the tyrosine receptor kinase B and C (Trk B, C), BDNF, neurotrophin 3 (NT3), Calretinin, etc.
文摘Asphalt mow strips are typically used as vegetation barriers around guardrail posts in the design of roadside safety structures. Asphalt mow strips have historically been modeled as a rigid layer in simulations;this assumption results in significant ground level restraint on the guardrail post. However, experiments have shown that asphalt rupture should be considered in the analysis of the response of guardrail posts embedded in mow strips. The present study investigates the effect of asphalt material properties and mow strip geometry on guardrail post performance using finite element simulations. Numerical simulations are performed and correlated with results from static experiments and material testing. The test simulations and experimental results are used to evaluate the response of guardrail posts with various mow strip designs to predict the level of restraint from the asphalt layer. The model is then used to investigate the effects of asphalt material properties and mow strip geometry on the overall performance of the system. The results demonstrate that including asphalt rupture in numerical simulations is essential in accurately predicting the behavior of guardrail posts installed in asphalt mow strips. In addition, mow strip geometry along with asphalt material properties significantly affect the guardrail post response.
基金Supported by Shiraz University of Medical Sciences,Vice chancellor for research and technology,No.91-6347
文摘AIM: To quantify the exposure levels and to assess pulmonary reactions associated with exposure to cotton dust and its biological contaminants.METHODS: All employees(51 male workers) of a ginning industry as well as 51 referent unexposed subjects from clerical staff of an educational center were investigated. Atmospheric concentrations of cotton dust and bioaerosols were measured. Furthermore, bacterial and fungal genera and species were identified by an expert microbiologist and an experienced mycologist. A standard respiratory symptom questionnaire was filled out for the subjects and they underwent multiple spirometry tests, at the beginning and at the end of work season as well as prior to(pre-exposure base line values) and at end of the first shift of workweek(post exposure). RESULTS: Gram negative bacteria including Enterobacter agglomerans and Pseudomonas spp. were found to be the dominant bacterial species and genera, respectively. Similarly, dominant fungi were identified tobe Mucor sp. Rhizopus sp. and Aspergillus niger. Mean atmospheric concentrations of cotton dust in ginning and outdoor areas were found to be 35.2 and 6.8 mg/m3, respectively. The prevalence rates of cough, phlegm, wheezing, dyspenea and grade 1/2 byssinosis among the exposed subjects were significantly higher than their corresponding values for the unexposed employees(P < 0.05). Additionally, significant differences were noted in the mean baseline value(preshift) of vital capacity, forced expiratory volume in the first second(FEV1)and FEV1/forced vital capacity ratio of the exposed subjects when compared with those of their referent counterparts. Similarly, significant cross shift decrements were noted in most parameters of pulmonary function of the exposed subjects.CONCLUSION: Seasonal exposure to cotton dust induces both acute, partially reversible, and chronic irreversible decrements in the lungs' functional capacities as well as increased prevalence of respiratory symptoms.
文摘Background: CHF (Congestive Heart Failure) is one of the most important causes of mortality and morbidity in the world. Diuretics such as spironolactone can decrease pulmonary congestion and reduce the amount of fibrosis in CHF patients. The goal was to assess whether spironolactone can decrease air way resistance and can we follow up the effect of diuretic therapy in patients of heart failure quantitatively by means of impulse oscillometry. Methods: It was clinical trial which performed in Ahvaz teaching hospital. 24 patients with congestive heart failure (CHF) which was classified as functional class II-IV and had EF Result: The age of patient was 61 ± 10 and the age of control was 57 ± 7 years old. The data of oscillometry before and after spironolactone were X5 (−0.14 ± 0.05 vs −0.14 ± 0.05, P: 0.93), R5 (0.39 ± 0.21 vs 0.39 ± 0.15, P: 0.35), X20 (−0.04 ± 0.06 vs −0.06 ± 0.06, P: 0.37), R20 (0.04 ± 0.03 vs 0.06 ± 0.06, P: 0.37), Zrs (0.39 ± 0.21 vs 0.39 ± 0.15, P: 0.35). Conclusion: There was a trend toward reduction of peripheral airway resistances in CHF patients than controls with use of 1 month of spironolactone. Although there was not significant change in the number of X5, R5, X20, R20 occurred the trend toward reduction of number triggers the point that oscillometry can be used for quantitative follow up of CHF patients.
基金supported by Islamic Azad University, Shahreza Branch
文摘The elimination of the silica matrix of composites by HF occurred by a two-step reaction deposition of a Cs2.5H0.5PW12O40(CsHPW) salt nanocrystal.We used 2D hexagonal SBA-15 silica as a template for the nanofabrication of CsHPW nanoparticles.Nanocast CsHPW materials are stable against leaching and colloidization in polar solvents.The catalytic performance of the nanocast CsHPW materi-als exceeded that of bulk Cs2.5H0.5PW12O40,which is the most active among the acidic HPW salts.A series of novel 1,3,5-triaryl-pyrazoline derivatives were synthesized by the reaction between chalcone and phenylhydrazine in high yield in the presence of CsHPW salt nanocrystals.
文摘Since its first release in 2008,Norine remains the unique resource completely devoted to nonribosomal peptides(NRPs).They are very attractive microbial secondary metabolites,displaying a remarkable diversity of structure and functions.Norine(http://bioinfo.lifl.fr/NRP)includes a database now containing more than 1160 annotated peptides and user-friendly interfaces enabling the querying of the database,through the annotations or the structure of the peptides.Dedicated tools are associated for structural comparison of the compounds and prediction of their biological activities.In this paper,we start by describing the knowledgebase and the dedicated tools.We then present some user cases to show how useful Norine is for the discovery of novel nonribosomal peptides.
文摘BACKGROUND AND OBJECTIVE Coccydynia can lead to significant functional disability and worsening of quality of life if not properly managed. In this study, we aim to assess the outcomes of extracorporeal shock wave therapy in patients with coccydynia. METHODS A prospective case series study was carried out from January to December 2015. Twenty-three patients, mean age of 38.3±12.1 (range 18-64), were included. The majority were females (13;56.5%), had pain for at least 6 weeks (17;73.9%) and had trauma to the sacrococcygeal region (17;73.9%). They had three sessions (one session per week for three consecutive weeks) of focused shock wave therapy directed to the maximal point of coccygeal tenderness. Numerical pain scale and Oswestry disability index were used to assess outcome. RESULTS Six (26.1%) patients did not complete the follow-up because of no, or minimal, improvement of their pain. After 6 months of follow-up, the median numerical pain scale significantly decreased from 7.0±4.0 to 2.0±2.0 among the 17 patients with coccydynia (P<0.001). The median Oswestry disability index improved from 24.0±9.0 before therapy to 8.0±9.0 at final follow-up (P<0.001). Before treatment, 12 (70.6%) patients had moderate-to-severe disability. In contrast, no patients had severe disability and only one (5.9%) patient had moderate disability at final follow-up (P<0.001). CONCLUSION Extracorporeal shock wave therapy had favorable outcomes in treating coccydynia. The majority of patients had partial relief of their pain and disability following this therapy.
