An investigation was performed on the suitability of carbon materials, metallic lead and its alloys as substrates for zinc negative electrode in acid PbO2-Zn single flow batteries. The zinc deposition process was carr...An investigation was performed on the suitability of carbon materials, metallic lead and its alloys as substrates for zinc negative electrode in acid PbO2-Zn single flow batteries. The zinc deposition process was carried out in the mediumofl mol.L 1H2SO4 at room temperature. No maximum current appears on the potentiostatic current transients for the zinc deposition on lead and its alloys. With increasing overpotential, the progressive nucleation turns to be a 3D-instantaneous nucleation process for the resin-graphite composite. Hydrogen evolution on the graphite composite is effectively suppressed with the doping of a polymer resin. The hydrogen evolution reaction on the lead is relatively weak, while on the lead alloys, it becomes serious to a certain degree. Although the ex- change current density of zinc deposition and dissolution process on the graphite composite is relatively low, the zinc corrosion is weakened to a great extent. With the increase of deposition time, zinc deposits are more compact. The cyclings of zinc galvanostatic charge-discharge on the graphite composite provide more than 90% of coulombic and 80% of energy efficiencies, and exhibit superior cycling stability during the first 10 cycles.展开更多
This study investigated the use of a product based on yacon (PBY) in microbiological, physical-chemical and intestinal characteristics of Wistar rats artificially constipated with Loperamide®. Thirty-two rats ...This study investigated the use of a product based on yacon (PBY) in microbiological, physical-chemical and intestinal characteristics of Wistar rats artificially constipated with Loperamide®. Thirty-two rats were divided into four groups: Control (C), Constipated Control (CC), PBY (not constipated) and Constipated PBY (PBYC). The dosage of 0.14 g of FOS+ inulin/kg was tested. Microbiota, pH and faeces characteristics of faeces and caecal contents were evaluated. Caecal weight, morphometry of caecal villi and the concentration of short-chain fatty acids were determined. Higher caecal weight was identified in the PBYC animals as well as higher width, height and depth of cripts. The PBY group showed the highest (p < 0.05) concentration of butyrate (93.2 ± 65.5 mmol/L). The supplementation with PBY positively altered the intestine epithelial tissue in constipated animals, keeping the integrity of the caecum crypts.展开更多
Objective: to explore the analysis and thinking of the results of two methods for unpaid blood donors in a certain area. Methods: 2000 blood samples from unpaid blood donors in a certain area were selected as the rese...Objective: to explore the analysis and thinking of the results of two methods for unpaid blood donors in a certain area. Methods: 2000 blood samples from unpaid blood donors in a certain area were selected as the research object. The detection method was two times of different manufacturers ELISA reagents (Xinchuang/Wantai/Kehua). Six people were tested (ID-NAT) for those who were negative for both times. If positive, they were split again, subject to the (Roche or Kehua reagents) test (six people). Results: the positive rate of HIV 1/HCV/HBV NAT initial screening was 0.5%. Six samples were positive by ELISA at the same time, and five samples were positive by identification, with the positive rate of identification being 83.33%. The positive blood samples for twice, once positive and once negative were classified as three retest positive samples, and the negative samples for twice were classified as one retest negative sample. The negative initial screening positive S/CO value was 13.75 ± 2.40, and the negative S/CO value was 8.06 ± 6.05;The minimum value of positive S/CO in the initial screening of positive retest is 8.07, the minimum value of negative S/CO is 10.12, the minimum value of positive S/CO in the initial screening of negative retest is 9.13, and the minimum value of negative S/CO is 1.02. Conclusion: the results of ELISA and single ID-NAT test for unpaid blood donors are significant. The two methods can improve the accuracy of blood sample test for unpaid blood donors, and can effectively ensure the safety of clinical blood transfusion treatment.展开更多
The capability to image, as well as control and manipulate single molecules such as nucleic acids(DNA or RNA) can greatly enrich our knowledge of the roles of individual biomolecules in cellular processes and their be...The capability to image, as well as control and manipulate single molecules such as nucleic acids(DNA or RNA) can greatly enrich our knowledge of the roles of individual biomolecules in cellular processes and their behavior in native environments. Here we summarize the recent advances of single nucleic acid imaging based on optical observation and force manipulation. We start by discussing the superiority of single molecule image, the central roles nucleic acids play in biosystems, and the significance of single molecule image towards nucleic acids. We then list a series of representative examples in brief to illustrate how nucleic acid of various morphologies has been imaged from different aspects, and what can be learned from such characterizations. Finally,concluding remarks on parts of which should be improved and outlook are outlined.展开更多
Single-nucleotide polymorphisms(SNPs)are recognized as one kind of major genetic variants in population scale.However,polymorphisms at the proteome level in population scale remain elusive.In the present study,we nam...Single-nucleotide polymorphisms(SNPs)are recognized as one kind of major genetic variants in population scale.However,polymorphisms at the proteome level in population scale remain elusive.In the present study,we named amino acid variances derived from SNPs within coding regions as single amino acid polymorphisms(SAPs)at the proteome level,and developed a pipeline of nontargeted and targeted proteomics to identify and quantify SAP peptides in human plasma.The absolute concentrations of three selected SAP-peptide pairs among 290 Asian individuals were measured by selected reaction monitoring(SRM)approach,and their associations with both obesity and diabetes were further analyzed.This work revealed that heterozygotes and homozygotes with various SAPs in a population could have different associations with particular traits.In addition,the SRM approach allows us for the first time to separately measure the absolute concentration of each SAP peptide in the heterozygotes,which also shows different associations with particular traits.展开更多
Single amino acid polymorphisms(SAPs),also known as non-synonymous single nucleotide polymorphisms(nsSNPs),are responsible for most of human genetic diseases.Discriminate the deleterious SAPs from neutral ones can hel...Single amino acid polymorphisms(SAPs),also known as non-synonymous single nucleotide polymorphisms(nsSNPs),are responsible for most of human genetic diseases.Discriminate the deleterious SAPs from neutral ones can help identify the disease genes and understand the mechanism of diseases.In this work,a method of deleterious SAP prediction at system level was established.Unlike most existing methods,our method not only considers the sequence and structure information,but also the network information.The integration of network information can improve the performance of deleterious SAP prediction.To make our method available to the public,we developed SySAP(a System-level predictor of deleterious Single Amino acid Polymorphisms),an easy-to-use and high accurate web server.SySAP is freely available at http://www.biosino.org/SySAP/and http://lifecenter.sgst.cn/SySAP/.展开更多
The objective of this study was to produce structured lipids(SLs)enriched in docosahexaenoic acid(DHA)by enzymatic interesterification of a medium-chain triacylglycerol(MCT)oil and docosahexaenoic acid single cell oil...The objective of this study was to produce structured lipids(SLs)enriched in docosahexaenoic acid(DHA)by enzymatic interesterification of a medium-chain triacylglycerol(MCT)oil and docosahexaenoic acid single cell oil(DHASCO),using immobilized lipases from Thermomyces lanuginosus(TL)and Candida rugosa(CR).The enzymes were screened for their effectiveness,and optimal conditions were employed to evaluate their ability to incorporate DHA or medium-chain fatty acids(MCFAs)into the triacylglycerol backbone.Fatty acid composition,regiospecific distribution,and oxidative stability were assessed in both the original and structured lipids.Structured lipids were prepared under ultrasonic-assisted enzymatic interesterification,and their oxidative stability was evaluated using conjugated dienes(CD)and 2-thiobarbituric acid reactive substances(TBARS)assays.The results indicated that after 1 h of incubation,DHA content in the resultant product was reduced to 31.22%and 32.66%with TL and CR lipases,respectively.For MCFAs,long chain saturated fatty acids(LC-SFAs)and long chain polyunsaturated fatty acids(LC-PUFAs),the amounts were 35.29%,15.91%and 15.06%(TL:Thermomyces lanuginosus),and 25.92%,20.04%and 17.83%(CR:Candida rugosa),respectively.In DHASCO,DHA was predominantly esterified to the sn-2 position,while MCFAs occupied mainly the sn-1 and sn-3 positions.In MCT,MCFAs were esterified to all positions,but as the chain length increased from C8 to C16,saturated FAs decreased in the sn-1 and sn-2 positions but not in the sn-3 position.In novel structured lipids so produced,DHA was mainly attached to the sn-2 position,with C8:0 to C16:0 esterified to sn-1,3 positions.Enzymatically modified oil generally had higher CD and TBARS values compared to their unmodified counterparts.These findings demonstrate potential for rational design of structured lipids,offering a venue to tailor their composition and enhanced potential nutritional value.展开更多
In this study,acid fracturing treatments were simulated for a tight limestone reservoir within a shale formation using FRACPRO software.The purpose was to investigate the optimum acid fracturing design that leads to a...In this study,acid fracturing treatments were simulated for a tight limestone reservoir within a shale formation using FRACPRO software.The purpose was to investigate the optimum acid fracturing design that leads to a higher fracture etched length and width,and higher fracture conductivity.Moreover,the impact of the rock-acid contact time and whether to consider a post-flush or fluids flowback,on the acid fracturing outcomes were also investigated.A simple geological model was constructed which consists of different lithological layers.Different acid fracturing design scenarios were considered starting from a single stage of acid injection to multi-stage treatment.In multi-stage acid treatment,alternate acid-slickwater injection was considered.Plain HCl acids with different concentrations and other acids that are already included in FRACPRO database were used.The results showed that the acid loss during post-flush is among the main problems of the acid fracturing in tight carbonate shale reservoir.For the single stage of acid injection,it is recommended to flow back the acid after well shut-in instead of considering a post-flush stage.The multi-stage alternate acid slickwater injection reduces or even eliminated the acid loss.However,it is recommended to inject a slickwater before well shut-in to reduce the rock-acid contact time,thus reducing the formation damage.The results also showed that the created fracture etched width decreases and the fracture etched length increases as the fracturing stages increase.In this study,because of the low carbonate layer permeability and compressive strength,a two-stage alternate 28%HCl and slickwater injection with a post-flush stage is recommended.展开更多
基金Supported by the National Basic Research Program(973 Program)of China(2010CB227201)the State Key Program of National Natural Science of China(21236003)+2 种基金the National Natural Science Foundation of China(21476022)the Fundamental Research Funds for the Central Universities(JD1515 and YS1406)Beijing Higher Education Young Elite Teacher Project(YETP0509)
文摘An investigation was performed on the suitability of carbon materials, metallic lead and its alloys as substrates for zinc negative electrode in acid PbO2-Zn single flow batteries. The zinc deposition process was carried out in the mediumofl mol.L 1H2SO4 at room temperature. No maximum current appears on the potentiostatic current transients for the zinc deposition on lead and its alloys. With increasing overpotential, the progressive nucleation turns to be a 3D-instantaneous nucleation process for the resin-graphite composite. Hydrogen evolution on the graphite composite is effectively suppressed with the doping of a polymer resin. The hydrogen evolution reaction on the lead is relatively weak, while on the lead alloys, it becomes serious to a certain degree. Although the ex- change current density of zinc deposition and dissolution process on the graphite composite is relatively low, the zinc corrosion is weakened to a great extent. With the increase of deposition time, zinc deposits are more compact. The cyclings of zinc galvanostatic charge-discharge on the graphite composite provide more than 90% of coulombic and 80% of energy efficiencies, and exhibit superior cycling stability during the first 10 cycles.
基金supported by the National Council of Scientific and Technological Development—CNPqthe Foundation for Research Support of the State of Minas Gerais—FAPEMIG.
文摘This study investigated the use of a product based on yacon (PBY) in microbiological, physical-chemical and intestinal characteristics of Wistar rats artificially constipated with Loperamide®. Thirty-two rats were divided into four groups: Control (C), Constipated Control (CC), PBY (not constipated) and Constipated PBY (PBYC). The dosage of 0.14 g of FOS+ inulin/kg was tested. Microbiota, pH and faeces characteristics of faeces and caecal contents were evaluated. Caecal weight, morphometry of caecal villi and the concentration of short-chain fatty acids were determined. Higher caecal weight was identified in the PBYC animals as well as higher width, height and depth of cripts. The PBY group showed the highest (p < 0.05) concentration of butyrate (93.2 ± 65.5 mmol/L). The supplementation with PBY positively altered the intestine epithelial tissue in constipated animals, keeping the integrity of the caecum crypts.
文摘Objective: to explore the analysis and thinking of the results of two methods for unpaid blood donors in a certain area. Methods: 2000 blood samples from unpaid blood donors in a certain area were selected as the research object. The detection method was two times of different manufacturers ELISA reagents (Xinchuang/Wantai/Kehua). Six people were tested (ID-NAT) for those who were negative for both times. If positive, they were split again, subject to the (Roche or Kehua reagents) test (six people). Results: the positive rate of HIV 1/HCV/HBV NAT initial screening was 0.5%. Six samples were positive by ELISA at the same time, and five samples were positive by identification, with the positive rate of identification being 83.33%. The positive blood samples for twice, once positive and once negative were classified as three retest positive samples, and the negative samples for twice were classified as one retest negative sample. The negative initial screening positive S/CO value was 13.75 ± 2.40, and the negative S/CO value was 8.06 ± 6.05;The minimum value of positive S/CO in the initial screening of positive retest is 8.07, the minimum value of negative S/CO is 10.12, the minimum value of positive S/CO in the initial screening of negative retest is 9.13, and the minimum value of negative S/CO is 1.02. Conclusion: the results of ELISA and single ID-NAT test for unpaid blood donors are significant. The two methods can improve the accuracy of blood sample test for unpaid blood donors, and can effectively ensure the safety of clinical blood transfusion treatment.
基金supported by the National Natural Science Foundation of China (21525523, 21574048, 21375042, 21405054)the National Basic Research Program of China (2015CB932600, 2013CB933000)+1 种基金the Special Fund for Strategic New Industry Development of Shenzhen, China (JCYJ20150616144425376)1000 Young Talent (to Fan Xia)
文摘The capability to image, as well as control and manipulate single molecules such as nucleic acids(DNA or RNA) can greatly enrich our knowledge of the roles of individual biomolecules in cellular processes and their behavior in native environments. Here we summarize the recent advances of single nucleic acid imaging based on optical observation and force manipulation. We start by discussing the superiority of single molecule image, the central roles nucleic acids play in biosystems, and the significance of single molecule image towards nucleic acids. We then list a series of representative examples in brief to illustrate how nucleic acid of various morphologies has been imaged from different aspects, and what can be learned from such characterizations. Finally,concluding remarks on parts of which should be improved and outlook are outlined.
基金supported by the grants from the Ministry of Science and Technology(2011CB910200,2011CB910601)a grant from the National Natural Science Foundation of China(30821065)the grants from the Knowledge Innovation Program of the Chinese Academy of Sciences(KSCX1-YW-02,KJCX2-YW-M15).
文摘Single-nucleotide polymorphisms(SNPs)are recognized as one kind of major genetic variants in population scale.However,polymorphisms at the proteome level in population scale remain elusive.In the present study,we named amino acid variances derived from SNPs within coding regions as single amino acid polymorphisms(SAPs)at the proteome level,and developed a pipeline of nontargeted and targeted proteomics to identify and quantify SAP peptides in human plasma.The absolute concentrations of three selected SAP-peptide pairs among 290 Asian individuals were measured by selected reaction monitoring(SRM)approach,and their associations with both obesity and diabetes were further analyzed.This work revealed that heterozygotes and homozygotes with various SAPs in a population could have different associations with particular traits.In addition,the SRM approach allows us for the first time to separately measure the absolute concentration of each SAP peptide in the heterozygotes,which also shows different associations with particular traits.
基金by the National Basic Research Program of China(973 Program)(Grant Nos.2011CB910204,2010CB529206,and 2010CB912702)Research Program of the Chinese Academy of Sciences(KSCX2-EW-R-04,KSCX2-YW-R-190,2011KIP204)+3 种基金National Natural Science Foundation of China(Grant Nos.30900272 and 31070752)National Key Technology R&D Program in the 11th Five Year Plan of China(No.2008BAI64B01)National High-Tech R&D Program of China(863 Program)(Grant No.2009AA02Z304)National Scientific-Basic Special Fund(No.2009FY120100).
文摘Single amino acid polymorphisms(SAPs),also known as non-synonymous single nucleotide polymorphisms(nsSNPs),are responsible for most of human genetic diseases.Discriminate the deleterious SAPs from neutral ones can help identify the disease genes and understand the mechanism of diseases.In this work,a method of deleterious SAP prediction at system level was established.Unlike most existing methods,our method not only considers the sequence and structure information,but also the network information.The integration of network information can improve the performance of deleterious SAP prediction.To make our method available to the public,we developed SySAP(a System-level predictor of deleterious Single Amino acid Polymorphisms),an easy-to-use and high accurate web server.SySAP is freely available at http://www.biosino.org/SySAP/and http://lifecenter.sgst.cn/SySAP/.
基金the Natural Sciences and Engineering Research Council(NSERC)of Canada for a Discovery Grant(RGPN to FS and the Vietnam International Education Development(VIED)for a scholarship NVL.
文摘The objective of this study was to produce structured lipids(SLs)enriched in docosahexaenoic acid(DHA)by enzymatic interesterification of a medium-chain triacylglycerol(MCT)oil and docosahexaenoic acid single cell oil(DHASCO),using immobilized lipases from Thermomyces lanuginosus(TL)and Candida rugosa(CR).The enzymes were screened for their effectiveness,and optimal conditions were employed to evaluate their ability to incorporate DHA or medium-chain fatty acids(MCFAs)into the triacylglycerol backbone.Fatty acid composition,regiospecific distribution,and oxidative stability were assessed in both the original and structured lipids.Structured lipids were prepared under ultrasonic-assisted enzymatic interesterification,and their oxidative stability was evaluated using conjugated dienes(CD)and 2-thiobarbituric acid reactive substances(TBARS)assays.The results indicated that after 1 h of incubation,DHA content in the resultant product was reduced to 31.22%and 32.66%with TL and CR lipases,respectively.For MCFAs,long chain saturated fatty acids(LC-SFAs)and long chain polyunsaturated fatty acids(LC-PUFAs),the amounts were 35.29%,15.91%and 15.06%(TL:Thermomyces lanuginosus),and 25.92%,20.04%and 17.83%(CR:Candida rugosa),respectively.In DHASCO,DHA was predominantly esterified to the sn-2 position,while MCFAs occupied mainly the sn-1 and sn-3 positions.In MCT,MCFAs were esterified to all positions,but as the chain length increased from C8 to C16,saturated FAs decreased in the sn-1 and sn-2 positions but not in the sn-3 position.In novel structured lipids so produced,DHA was mainly attached to the sn-2 position,with C8:0 to C16:0 esterified to sn-1,3 positions.Enzymatically modified oil generally had higher CD and TBARS values compared to their unmodified counterparts.These findings demonstrate potential for rational design of structured lipids,offering a venue to tailor their composition and enhanced potential nutritional value.
文摘In this study,acid fracturing treatments were simulated for a tight limestone reservoir within a shale formation using FRACPRO software.The purpose was to investigate the optimum acid fracturing design that leads to a higher fracture etched length and width,and higher fracture conductivity.Moreover,the impact of the rock-acid contact time and whether to consider a post-flush or fluids flowback,on the acid fracturing outcomes were also investigated.A simple geological model was constructed which consists of different lithological layers.Different acid fracturing design scenarios were considered starting from a single stage of acid injection to multi-stage treatment.In multi-stage acid treatment,alternate acid-slickwater injection was considered.Plain HCl acids with different concentrations and other acids that are already included in FRACPRO database were used.The results showed that the acid loss during post-flush is among the main problems of the acid fracturing in tight carbonate shale reservoir.For the single stage of acid injection,it is recommended to flow back the acid after well shut-in instead of considering a post-flush stage.The multi-stage alternate acid slickwater injection reduces or even eliminated the acid loss.However,it is recommended to inject a slickwater before well shut-in to reduce the rock-acid contact time,thus reducing the formation damage.The results also showed that the created fracture etched width decreases and the fracture etched length increases as the fracturing stages increase.In this study,because of the low carbonate layer permeability and compressive strength,a two-stage alternate 28%HCl and slickwater injection with a post-flush stage is recommended.
