Wenzhou has improved its environmental quality because of comprehensive environmental remediation;nevertheless,the semen quality of infertile males remains unclear.This study determined whether better environmental qu...Wenzhou has improved its environmental quality because of comprehensive environmental remediation;nevertheless,the semen quality of infertile males remains unclear.This study determined whether better environmental quality improved semen quality in this region.We recorded semen quality data from 22962 infertile males from January 2014 to November 2019 at the Center for Reproductive Health of The First Affiliated Hospital of Wenzhou Medical University(Wenzhou,China).Patients were predominantly 30–35 years old(33.1%)and workers(82.0%),with high school education or lower(77.6%);more than a half of the patients(52.6%)were Wenzhou household registration;and most patients(77.5%)had abnormal semen quality.Patients who were older than 40 years and workers,and those with Wenzhou household registration,had significantly worse semen quality(all P<0.05).From 2014 to 2019,progressive sperm motility,total sperm motility,and semen volume showed increasing linear trends in all patients(P=0.021,0.030,and 0.005,respectively),yet normal sperm morphology showed a linearly decreasing trend(P=0.046).Sensitivity analyses for subgroups yielded similar results.In conclusion,the improvement of environmental quality and better function of the accessory glands are associated with progressive sperm motility,total sperm motility,and semen volume.Normal sperm morphology is influenced by occupational exposures and personal lifestyle and does not improve with environmental quality.展开更多
This study analyzed the trend in semen quality of infertile male patients in Wenzhou,China,based on the data obtained from 38905 patients during 2008-2016 in The First Affiliated Hospital of Wenzhou Medical University...This study analyzed the trend in semen quality of infertile male patients in Wenzhou,China,based on the data obtained from 38905 patients during 2008-2016 in The First Affiliated Hospital of Wenzhou Medical University(Wenzhou,China).The results showed that only 24.9%of the patients had normal semen quality.For the semen quality of infertile male patients,that of the workers and 40-year-olds was significantly worse than the other occupational and age groups.For all the infertile patients,low semen volume,asthenozoospermia,and teratozoospermia accounted for 8.4%,50.5%,and 54.1%,respectively.During 2008-2016,the annual mean percentage of fast forward motile spermatozoa,percentage of total forward motile spermatozoa,and percentage of spermatozoa with normal morphology decreased linearly with slopes of-2.11,-2.59,and-0.70,respectively.The proportion of patients with asthenozoospermia and multi-abnormal spermatozoa increased during 2008-2016 with slopes of 4.70 and 4.87,respectively,while for low semen volume,it decreased with a slope of-0.47 in the same time period.The proportion of patients with teratozoospermia increased from 2008 to 2011 and from 2011 to 2016 with slopes of 17.10 and 2.09,respectively.In general,the deteriorating trend of semen quality of infertile male patients in Wenzhou was obvious.Future efforts should be made to reveal the adverse influences on semen quality,such as occupational exposure,environmental quality,and living habits.Furthermore,more pervasive reproduction health education is necessary.展开更多
In this study, the poly(L-lactide)/poly(D-lactide) (PLLA/PDLA) blends with different optical purities of PLLA and various molecular weights of PDLA are prepared by solution mixing, and the stereocomplex formatio...In this study, the poly(L-lactide)/poly(D-lactide) (PLLA/PDLA) blends with different optical purities of PLLA and various molecular weights of PDLA are prepared by solution mixing, and the stereocomplex formation and phase separation behaviors of these blends are investigated. Results reveal that optical purity and molecular weight do not vary the crystal structure of PLA stereocomplex (sc) and homochiral crystallites (hc). As the optical purity increasing in the blends, the melting temperature of sc (Tsc) and the content of sc (AHsc) increased, while the melting temperature of hc (Thin) hardly changes, although the content ofhc (AHhm) decreased gradually. The Tsc and AHsc are also enhanced as the molecular weight of PDLA reduces, and the AHhm reduces rapidly even though the Thin does not vary apparently. With lower optical purities of PLLA and higher molecular weights of PDLA, three types of crystals form in the blends, i.e., PLA sc, PLLA hc and PDLA hc. As molecular weight decreases and optical purity enhances, the crystal phase decreases to two (sc and PDLA hc), and one (sc) finally. This investigation indicates that the phase separation behavior between PLLA and PDLA in the PLLA/PDLA blends not only depends on molecular weights, but also relies on the optical purities of polymers.展开更多
Poly(ether urethane)s (PEU), including PEUI 15 and PEUH15, were prepared through chain-extension reaction of poly(ethylene glycol) (PEG-1500) using diisocyanate as a chain extender, including isophorone diisoc...Poly(ether urethane)s (PEU), including PEUI 15 and PEUH15, were prepared through chain-extension reaction of poly(ethylene glycol) (PEG-1500) using diisocyanate as a chain extender, including isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI). These PEUs were used to toughen polylactide (PLA) by physical and reactive blending. Thermal, morphological, mechanical and aging properties of the blends were investigated in detail. These PEUs were partially compatible with PLA. The elongation at break of the reactive blends in the presence of triphenyl phosphate (TPP) for PLA with PEUH15 or PEUI15 was much higher than that of the physical blends. The aging test was carried out at -20 ~C for 50 h in order to accelerate the crystallization of PEUs. The PEUs in the PLA/PEU blends produced crystallization and formed new phase separation with PLA, resulting in the declined toughness of blends. Fortunately, under the aging condition, although PEUH15 in blends could also form crystallization, the reactive blend of PLA/PEUH15/TPP(80/20/2) bad higher toughness than the other blends. The elongation at break of PLA/PEUH 15/TPP(80/20/2) dropped to 287% for the aging blend from 350% for the original blend. The tensile strength and modulus of PLA/PEUH15/TPP blend did not change obviously because of the crystallization of PEUH 15.展开更多
基金This study was supported by the Project of Wenzhou Science and Technology Bureau(No.Y2020048)the Education Project of Zhejiang Province(No.Y202146906)+1 种基金the Science and Technology Planning Project of Wenzhou(S2020002)the Research Project of Wenzhou Medical University(KJHX2014).
文摘Wenzhou has improved its environmental quality because of comprehensive environmental remediation;nevertheless,the semen quality of infertile males remains unclear.This study determined whether better environmental quality improved semen quality in this region.We recorded semen quality data from 22962 infertile males from January 2014 to November 2019 at the Center for Reproductive Health of The First Affiliated Hospital of Wenzhou Medical University(Wenzhou,China).Patients were predominantly 30–35 years old(33.1%)and workers(82.0%),with high school education or lower(77.6%);more than a half of the patients(52.6%)were Wenzhou household registration;and most patients(77.5%)had abnormal semen quality.Patients who were older than 40 years and workers,and those with Wenzhou household registration,had significantly worse semen quality(all P<0.05).From 2014 to 2019,progressive sperm motility,total sperm motility,and semen volume showed increasing linear trends in all patients(P=0.021,0.030,and 0.005,respectively),yet normal sperm morphology showed a linearly decreasing trend(P=0.046).Sensitivity analyses for subgroups yielded similar results.In conclusion,the improvement of environmental quality and better function of the accessory glands are associated with progressive sperm motility,total sperm motility,and semen volume.Normal sperm morphology is influenced by occupational exposures and personal lifestyle and does not improve with environmental quality.
基金the Major Project of National Key Research and Development Program(2018YFC1004300).
文摘This study analyzed the trend in semen quality of infertile male patients in Wenzhou,China,based on the data obtained from 38905 patients during 2008-2016 in The First Affiliated Hospital of Wenzhou Medical University(Wenzhou,China).The results showed that only 24.9%of the patients had normal semen quality.For the semen quality of infertile male patients,that of the workers and 40-year-olds was significantly worse than the other occupational and age groups.For all the infertile patients,low semen volume,asthenozoospermia,and teratozoospermia accounted for 8.4%,50.5%,and 54.1%,respectively.During 2008-2016,the annual mean percentage of fast forward motile spermatozoa,percentage of total forward motile spermatozoa,and percentage of spermatozoa with normal morphology decreased linearly with slopes of-2.11,-2.59,and-0.70,respectively.The proportion of patients with asthenozoospermia and multi-abnormal spermatozoa increased during 2008-2016 with slopes of 4.70 and 4.87,respectively,while for low semen volume,it decreased with a slope of-0.47 in the same time period.The proportion of patients with teratozoospermia increased from 2008 to 2011 and from 2011 to 2016 with slopes of 17.10 and 2.09,respectively.In general,the deteriorating trend of semen quality of infertile male patients in Wenzhou was obvious.Future efforts should be made to reveal the adverse influences on semen quality,such as occupational exposure,environmental quality,and living habits.Furthermore,more pervasive reproduction health education is necessary.
基金financially supported by the National Natural Science Foundation of China(Nos.5127319851373169+4 种基金510330035130317651321062 and 51403089)863 Program(No.2011AA02A202)from the Ministry of Science and Technology of ChinaInnovative Research Group(No.51321062)
文摘In this study, the poly(L-lactide)/poly(D-lactide) (PLLA/PDLA) blends with different optical purities of PLLA and various molecular weights of PDLA are prepared by solution mixing, and the stereocomplex formation and phase separation behaviors of these blends are investigated. Results reveal that optical purity and molecular weight do not vary the crystal structure of PLA stereocomplex (sc) and homochiral crystallites (hc). As the optical purity increasing in the blends, the melting temperature of sc (Tsc) and the content of sc (AHsc) increased, while the melting temperature of hc (Thin) hardly changes, although the content ofhc (AHhm) decreased gradually. The Tsc and AHsc are also enhanced as the molecular weight of PDLA reduces, and the AHhm reduces rapidly even though the Thin does not vary apparently. With lower optical purities of PLLA and higher molecular weights of PDLA, three types of crystals form in the blends, i.e., PLA sc, PLLA hc and PDLA hc. As molecular weight decreases and optical purity enhances, the crystal phase decreases to two (sc and PDLA hc), and one (sc) finally. This investigation indicates that the phase separation behavior between PLLA and PDLA in the PLLA/PDLA blends not only depends on molecular weights, but also relies on the optical purities of polymers.
基金financially supported by the National Natural Science Foundation of China(Nos.51573178,51390480,51203155,51403199 and 51303176)the National High Technology Research and Development Program("863" Program) of China(No.2015AA034004)
文摘Poly(ether urethane)s (PEU), including PEUI 15 and PEUH15, were prepared through chain-extension reaction of poly(ethylene glycol) (PEG-1500) using diisocyanate as a chain extender, including isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI). These PEUs were used to toughen polylactide (PLA) by physical and reactive blending. Thermal, morphological, mechanical and aging properties of the blends were investigated in detail. These PEUs were partially compatible with PLA. The elongation at break of the reactive blends in the presence of triphenyl phosphate (TPP) for PLA with PEUH15 or PEUI15 was much higher than that of the physical blends. The aging test was carried out at -20 ~C for 50 h in order to accelerate the crystallization of PEUs. The PEUs in the PLA/PEU blends produced crystallization and formed new phase separation with PLA, resulting in the declined toughness of blends. Fortunately, under the aging condition, although PEUH15 in blends could also form crystallization, the reactive blend of PLA/PEUH15/TPP(80/20/2) bad higher toughness than the other blends. The elongation at break of PLA/PEUH 15/TPP(80/20/2) dropped to 287% for the aging blend from 350% for the original blend. The tensile strength and modulus of PLA/PEUH15/TPP blend did not change obviously because of the crystallization of PEUH 15.