In this study,umami taste intensity(UTI)and umami taste components in chicken breast(CB)and chickenspices blends were characterized using sensory and instrumental analysis.Our main objective was to assess the aroma-um...In this study,umami taste intensity(UTI)and umami taste components in chicken breast(CB)and chickenspices blends were characterized using sensory and instrumental analysis.Our main objective was to assess the aroma-umami taste interactions in different food matrices and reconcile the aroma-taste perception to assist future product development.The impact of key aroma,including vegetable-note"2-pentylfuran",meaty"methional",green"hexanal",and spicy-note-estragole and caryophyllene"on UTI was evaluated in monosodium glutamate and chicken extract.We found that spices significantly decreased UTI and umami taste components in CB.Interestingly,the perceptually similar odorants and tastants exhibited the potential to enhance UTI in food matrices.Methional was able to increase the UTI,whereas spicy and green-note components could reduce the UTI significantly.This information would be valuable to food engineers and formulators in aroma selection to control the UTI perceived by consumers,thus,improving the quality and acceptability of the chicken products.展开更多
Sanhuang chicken is a popular native breed in China and well-known for delicious flavour.Spices could enhance the chicken meat flavour and work well in preservation.Chinese 5-spice blend(CS)and garam masala(GM)are rou...Sanhuang chicken is a popular native breed in China and well-known for delicious flavour.Spices could enhance the chicken meat flavour and work well in preservation.Chinese 5-spice blend(CS)and garam masala(GM)are routinely using spices in China and Pakistan,respectively.The flavour profiles of Sanhuang chicken breast(CB)and its blends with CS and GM were obtained by electronic nose(E-nose),solid-phase microextraction gas chromatography-mass spectrometry(SPME GC-MS)and GC-ion mobility spectrometry(GC-IMS).Principal component analysis(PCA)efficiently discriminated the aroma profiles of three chicken formulations.The GC-chromatographs revealed the significant aroma alterations of chicken breast meat after marination with spices.Aldehydes were the major contributors of chicken aroma,while most of the aromatic hydrocarbons were generated by spices.Almost all chicken key-compounds produced by oxidation reaction were either reduced or eliminated by marination,showing the antioxidation capacity of spices leading to meat preservation.GC-IMS is not only a rapid and comprehensive detection method,but also proved to be more sensitive than GC-MS.The substantial role of both traditional spices in enhancing flavour quality of chicken meat,and their exposure as functional ingredients in Chinese and Pakistan cuisines could lead to the cross-cultural meat trade opportunities.展开更多
Tilapia is a freshwater fish group with a sustainable prospect but suffers off-notes appearing during cooking processes.To promote pleasant odorants by thermal cooking processes,tilapia fillets were cooked in differen...Tilapia is a freshwater fish group with a sustainable prospect but suffers off-notes appearing during cooking processes.To promote pleasant odorants by thermal cooking processes,tilapia fillets were cooked in different ways(roasting,microwave-heating,boiling and steaming).Their aroma profiles were analysed with special focus on off-notes and umami-enhancing odorants by principal component analysis,and correlated with the heating time,colour,moisture and water activity by partial least squares regression analysis.Results showed that the“green”and“earthy”off-notes were highly correlated with the boiling process(excess of water,short heating time),while most of the umami-enhancing odorants had a high association with the roasting process(low water content,long heating time,better Maillard reaction).This study indicated that roasting is the most adapted cooking process promoting Maillard-derived aromas,umami-enhancing aromas and meanwhile,reducing off-notes.This research helps in understanding the off-note generation in tilapia and promoting desirable umami-enhancing odorants.展开更多
The publisher regrets that the page range of this paper was incorrect due to production error,and we added al-a5 after page 107 to the pdf version to correct this mistake.
Control of texture structures is an effective method to reduce surface reflectivity and enhance the efficiency of solar cells.In this paper,pyramid structures are prepared on mono-crystalline silicon wafers by cyclode...Control of texture structures is an effective method to reduce surface reflectivity and enhance the efficiency of solar cells.In this paper,pyramid structures are prepared on mono-crystalline silicon wafers by cyclodextrin as surfactant to slow down the etching rate in alcohol-free alkali solution.Compared with volatile alcohol surfactant(e.g.isopropanol,IPA),the cyclodextrin not only possesses a relative high boiling point(1534.4℃),but displays non-toxic and biodegradable properties.Furthermore,the surface morphology,average reflectivity,surface recombination of mono-crystalline silicon wafers were studied in detail.The results show that cyclodextrin can decrease the size and depth of pyramid structures,and thus a lower average reflectivity of 7.5%was obtained.In addition,ray tracing simulation was performed to calculate the photo-generated carrier concentration of PN junction with different sizes of pyramids,and the conclusion is that the carrier concentration of small pyramids is much higher than that of large pyramids.Finally,the average efficiency of large-area mono-crystalline silicon PERC solar cells fabricated by cyclodextrin surfactant was 22.69%,which was 0.43%absolutely higher than that of conventional IPA surfactant.展开更多
Understanding how human leukocyte antigen(HLA)polymorphism affects both the susceptibility and severity of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection will help to identify individuals at high...Understanding how human leukocyte antigen(HLA)polymorphism affects both the susceptibility and severity of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection will help to identify individuals at higher risk to better manage and prioritize vaccination at the clinical level and explain the differences in epidemic trends in different regions at the epidemiological level.This study compared the frequencies of HLA class I alleles(HLA-A,B)in 214 coronavirus disease 2019(COVID-19)patients with different disease severity and 35 healthy controls and analyzed the correlations between specific HLA alleles and disease severity and T cell memory.The results showed no significant difference in HLA allele frequencies between COVID-19 patients and healthy controls(P>0.05).The allele HLA-B*13:02 was significantly correlated with the disease severity of COVID-19 patients(P=0.006).After adjustment for age and disease severity,the T cell responses of COVID-19 convalescents with the allele HLA-B*40:01 may be lower at six months(P=0.044)and 12 months(P=0.069).Moreover,these results may be due to their rare peptide anchors by analyzing the binding peptide motifs of these HLA alleles.The study may be valuable for investigating the potential association of specific HLA alleles with SARS-CoV-2 infection.展开更多
In this paper,we prove the optimal error estimates in L2 norm of the semidiscrete local discontinuous Galerkin(LDG)method for the thin film epitaxy problem without slope selection.To relax the severe time step restric...In this paper,we prove the optimal error estimates in L2 norm of the semidiscrete local discontinuous Galerkin(LDG)method for the thin film epitaxy problem without slope selection.To relax the severe time step restriction of explicit time marching methods,we employ a class of exponential time differencing(ETD)schemes for time integration,which is based on a linear convex splitting principle.Numerical experiments of the accuracy and long time simulations are given to show the efficiency and capability of the proposed numerical schemes.展开更多
It is well known that calcium arsenates may not be a good choice for arsenic removal and immobilization in hydrometallurgical practices.However,they are still produced at some plants in the world due to various reason...It is well known that calcium arsenates may not be a good choice for arsenic removal and immobilization in hydrometallurgical practices.However,they are still produced at some plants in the world due to various reasons.Furthermore,calcium arsenates can also naturally precipitate under some specific environments.However,the transformation process of poorly crystalline calcium arsenates(PCCA)and the stability of these samples under atmospheric CO2 are not yet well understood.This work investigated the transformation process of PCCA produced by using different neutralization reagents(CaO vs.NaOH)with various Ca/As molar ratios at pH 7-12 in the presence of atmospheric CO2.After aging at room temperature for a period of time,for samples neutralized with NaOH and precipitated at pH 10 and 12,release of arsenic back into the liquid phase occurred.In contrast,for the samples precipitated at pH 8,the aqueous concentration of arsenic was observed to decrease.XRD,Raman,and SEM results suggested that the formation of various types of crystalline calcium carbonates and/or calcium arsenates controls the arsenic behavior.Moreover,the application of lime may enhance the stability of the generated PCCA.However,no matter what neutralization reagent is used,the stability of the generated PCCA is still of concern.展开更多
目的分析右美托咪定联合不同浓度罗哌卡因局部神经阻滞在老年腹股沟疝无张力修补术中的应用。方法2020年3月至2022年3月内蒙古包钢医院收治的老年腹股沟疝患者80例,采用随机数字表法分为A组与B组,各40例。2组均接受无张力疝修补术治疗,...目的分析右美托咪定联合不同浓度罗哌卡因局部神经阻滞在老年腹股沟疝无张力修补术中的应用。方法2020年3月至2022年3月内蒙古包钢医院收治的老年腹股沟疝患者80例,采用随机数字表法分为A组与B组,各40例。2组均接受无张力疝修补术治疗,A组接受0.1%罗哌卡因局部神经阻滞联合右美托咪定静脉泵入麻醉,B组采用0.2%罗哌卡因局部神经阻滞联合右美托咪定静脉泵入麻醉,术后均观察7 d。分析2组不同时间点生命体征,术后2 h、24 h疼痛、镇静、运动及认知评分,术前、术后7 d 2组血清Tau蛋白、β-淀粉样蛋白多肽42(Aβ42)蛋白以及Tau/Aβ42水平,术后24 h不良反应发生情况。结果切皮时(T2)B组心率低于入室(T0)、阻滞后15 min(T1)及手术结束时(T3),且低于A组(P<0.05),其余时刻心率、平均动脉压、脉搏血氧饱和度比较,差异无统计学意义(P>0.05)。与术后2 h比较,术后24 h 2组视觉模拟评分(VAS)、Bromage评分均降低,且A组VAS评分在2组中更低(P<0.05);术后24 h 2组简易智力状态检查量表(MMSE)评分均升高,且A组在2组中更高(P<0.05)。与术前比较,术后7 d 2组血清Tau蛋白、Tau/Aβ42水平均升高,但A组较B组更低;术后7 d 2组血清Aβ42蛋白降低,但A组较B组更高(P<0.05)。术后24 h,A组不良反应发生率较B组更低(7.50%vs27.50%,P<0.05)。结论0.1%罗哌卡因局部神经阻滞联合右美托咪定静脉泵入麻醉可稳定老年腹股沟疝无张力修补术患者生命体征,缓解疼痛,改善患者认知功能,安全性更高,分析与其调节Tau蛋白、Aβ42蛋白水平有关,值得临床进一步研究。展开更多
基金supported by the National Natural Science Foundation of China (31622042)。
文摘In this study,umami taste intensity(UTI)and umami taste components in chicken breast(CB)and chickenspices blends were characterized using sensory and instrumental analysis.Our main objective was to assess the aroma-umami taste interactions in different food matrices and reconcile the aroma-taste perception to assist future product development.The impact of key aroma,including vegetable-note"2-pentylfuran",meaty"methional",green"hexanal",and spicy-note-estragole and caryophyllene"on UTI was evaluated in monosodium glutamate and chicken extract.We found that spices significantly decreased UTI and umami taste components in CB.Interestingly,the perceptually similar odorants and tastants exhibited the potential to enhance UTI in food matrices.Methional was able to increase the UTI,whereas spicy and green-note components could reduce the UTI significantly.This information would be valuable to food engineers and formulators in aroma selection to control the UTI perceived by consumers,thus,improving the quality and acceptability of the chicken products.
基金funded by National Natural Science Foundation of China (Grant No. 32001824, 31972198, 31901816, 31901813, 32001827)
文摘Sanhuang chicken is a popular native breed in China and well-known for delicious flavour.Spices could enhance the chicken meat flavour and work well in preservation.Chinese 5-spice blend(CS)and garam masala(GM)are routinely using spices in China and Pakistan,respectively.The flavour profiles of Sanhuang chicken breast(CB)and its blends with CS and GM were obtained by electronic nose(E-nose),solid-phase microextraction gas chromatography-mass spectrometry(SPME GC-MS)and GC-ion mobility spectrometry(GC-IMS).Principal component analysis(PCA)efficiently discriminated the aroma profiles of three chicken formulations.The GC-chromatographs revealed the significant aroma alterations of chicken breast meat after marination with spices.Aldehydes were the major contributors of chicken aroma,while most of the aromatic hydrocarbons were generated by spices.Almost all chicken key-compounds produced by oxidation reaction were either reduced or eliminated by marination,showing the antioxidation capacity of spices leading to meat preservation.GC-IMS is not only a rapid and comprehensive detection method,but also proved to be more sensitive than GC-MS.The substantial role of both traditional spices in enhancing flavour quality of chicken meat,and their exposure as functional ingredients in Chinese and Pakistan cuisines could lead to the cross-cultural meat trade opportunities.
基金supported in part by the China Scholarship Council Fund
文摘Tilapia is a freshwater fish group with a sustainable prospect but suffers off-notes appearing during cooking processes.To promote pleasant odorants by thermal cooking processes,tilapia fillets were cooked in different ways(roasting,microwave-heating,boiling and steaming).Their aroma profiles were analysed with special focus on off-notes and umami-enhancing odorants by principal component analysis,and correlated with the heating time,colour,moisture and water activity by partial least squares regression analysis.Results showed that the“green”and“earthy”off-notes were highly correlated with the boiling process(excess of water,short heating time),while most of the umami-enhancing odorants had a high association with the roasting process(low water content,long heating time,better Maillard reaction).This study indicated that roasting is the most adapted cooking process promoting Maillard-derived aromas,umami-enhancing aromas and meanwhile,reducing off-notes.This research helps in understanding the off-note generation in tilapia and promoting desirable umami-enhancing odorants.
文摘The publisher regrets that the page range of this paper was incorrect due to production error,and we added al-a5 after page 107 to the pdf version to correct this mistake.
基金supported by the National Key Research and Development Program of China(2018YFB1500500,2018YFB1500200,2020YFB1506503)the National Natural Science Foundation of China(12035020,52072399,62074165,12175305,62104253 and 12105357)the Natural Science Foundation of Beijing Municipality(4192064,1212015)。
文摘Control of texture structures is an effective method to reduce surface reflectivity and enhance the efficiency of solar cells.In this paper,pyramid structures are prepared on mono-crystalline silicon wafers by cyclodextrin as surfactant to slow down the etching rate in alcohol-free alkali solution.Compared with volatile alcohol surfactant(e.g.isopropanol,IPA),the cyclodextrin not only possesses a relative high boiling point(1534.4℃),but displays non-toxic and biodegradable properties.Furthermore,the surface morphology,average reflectivity,surface recombination of mono-crystalline silicon wafers were studied in detail.The results show that cyclodextrin can decrease the size and depth of pyramid structures,and thus a lower average reflectivity of 7.5%was obtained.In addition,ray tracing simulation was performed to calculate the photo-generated carrier concentration of PN junction with different sizes of pyramids,and the conclusion is that the carrier concentration of small pyramids is much higher than that of large pyramids.Finally,the average efficiency of large-area mono-crystalline silicon PERC solar cells fabricated by cyclodextrin surfactant was 22.69%,which was 0.43%absolutely higher than that of conventional IPA surfactant.
基金The National Key Research and Development Program of China (2022YFC2604100)the National Natural Science Foundation of China (92269203)supported the study.
文摘Understanding how human leukocyte antigen(HLA)polymorphism affects both the susceptibility and severity of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection will help to identify individuals at higher risk to better manage and prioritize vaccination at the clinical level and explain the differences in epidemic trends in different regions at the epidemiological level.This study compared the frequencies of HLA class I alleles(HLA-A,B)in 214 coronavirus disease 2019(COVID-19)patients with different disease severity and 35 healthy controls and analyzed the correlations between specific HLA alleles and disease severity and T cell memory.The results showed no significant difference in HLA allele frequencies between COVID-19 patients and healthy controls(P>0.05).The allele HLA-B*13:02 was significantly correlated with the disease severity of COVID-19 patients(P=0.006).After adjustment for age and disease severity,the T cell responses of COVID-19 convalescents with the allele HLA-B*40:01 may be lower at six months(P=0.044)and 12 months(P=0.069).Moreover,these results may be due to their rare peptide anchors by analyzing the binding peptide motifs of these HLA alleles.The study may be valuable for investigating the potential association of specific HLA alleles with SARS-CoV-2 infection.
基金This work is supported by NSFC grants No.11601490.
文摘In this paper,we prove the optimal error estimates in L2 norm of the semidiscrete local discontinuous Galerkin(LDG)method for the thin film epitaxy problem without slope selection.To relax the severe time step restriction of explicit time marching methods,we employ a class of exponential time differencing(ETD)schemes for time integration,which is based on a linear convex splitting principle.Numerical experiments of the accuracy and long time simulations are given to show the efficiency and capability of the proposed numerical schemes.
基金supported by the National Natural Science Foundation of China (Nos. 41530643, 41673130 and 41877393)the National Key R&D Program of China (No. 2017YFD0800301)the Chinese Academy of Sciences (No. QYZDJ-SSW-DQC038)
文摘It is well known that calcium arsenates may not be a good choice for arsenic removal and immobilization in hydrometallurgical practices.However,they are still produced at some plants in the world due to various reasons.Furthermore,calcium arsenates can also naturally precipitate under some specific environments.However,the transformation process of poorly crystalline calcium arsenates(PCCA)and the stability of these samples under atmospheric CO2 are not yet well understood.This work investigated the transformation process of PCCA produced by using different neutralization reagents(CaO vs.NaOH)with various Ca/As molar ratios at pH 7-12 in the presence of atmospheric CO2.After aging at room temperature for a period of time,for samples neutralized with NaOH and precipitated at pH 10 and 12,release of arsenic back into the liquid phase occurred.In contrast,for the samples precipitated at pH 8,the aqueous concentration of arsenic was observed to decrease.XRD,Raman,and SEM results suggested that the formation of various types of crystalline calcium carbonates and/or calcium arsenates controls the arsenic behavior.Moreover,the application of lime may enhance the stability of the generated PCCA.However,no matter what neutralization reagent is used,the stability of the generated PCCA is still of concern.
文摘目的分析右美托咪定联合不同浓度罗哌卡因局部神经阻滞在老年腹股沟疝无张力修补术中的应用。方法2020年3月至2022年3月内蒙古包钢医院收治的老年腹股沟疝患者80例,采用随机数字表法分为A组与B组,各40例。2组均接受无张力疝修补术治疗,A组接受0.1%罗哌卡因局部神经阻滞联合右美托咪定静脉泵入麻醉,B组采用0.2%罗哌卡因局部神经阻滞联合右美托咪定静脉泵入麻醉,术后均观察7 d。分析2组不同时间点生命体征,术后2 h、24 h疼痛、镇静、运动及认知评分,术前、术后7 d 2组血清Tau蛋白、β-淀粉样蛋白多肽42(Aβ42)蛋白以及Tau/Aβ42水平,术后24 h不良反应发生情况。结果切皮时(T2)B组心率低于入室(T0)、阻滞后15 min(T1)及手术结束时(T3),且低于A组(P<0.05),其余时刻心率、平均动脉压、脉搏血氧饱和度比较,差异无统计学意义(P>0.05)。与术后2 h比较,术后24 h 2组视觉模拟评分(VAS)、Bromage评分均降低,且A组VAS评分在2组中更低(P<0.05);术后24 h 2组简易智力状态检查量表(MMSE)评分均升高,且A组在2组中更高(P<0.05)。与术前比较,术后7 d 2组血清Tau蛋白、Tau/Aβ42水平均升高,但A组较B组更低;术后7 d 2组血清Aβ42蛋白降低,但A组较B组更高(P<0.05)。术后24 h,A组不良反应发生率较B组更低(7.50%vs27.50%,P<0.05)。结论0.1%罗哌卡因局部神经阻滞联合右美托咪定静脉泵入麻醉可稳定老年腹股沟疝无张力修补术患者生命体征,缓解疼痛,改善患者认知功能,安全性更高,分析与其调节Tau蛋白、Aβ42蛋白水平有关,值得临床进一步研究。
基金supported by the National Natural Science Foundation of China(82161148008 and 81971501)the National Key Research and Development Program of China(2021YFC2301400,2020YFA0708103,and 2021YFC0863300)the Excellent Young Scientist Program of the National Natural Science Foundation of China(81822040)。
