The present study aims to establish a relationship between serum AMH levels and age in a large group of women living in Bulgaria, as well as to establish reference age-specific AMH levels in women that would serve as ...The present study aims to establish a relationship between serum AMH levels and age in a large group of women living in Bulgaria, as well as to establish reference age-specific AMH levels in women that would serve as an initial estimate of ovarian age. A total of 28,016 women on the territory of the Republic of Bulgaria were tested for serum AMH levels with a median age of 37.0 years (interquartile range 32.0 to 41.0). For women aged 20 - 29 years, the Bulgarian population has relatively high median levels of AMH, similar to women of Asian origin. For women aged 30 - 34 years, our results are comparable to those of women living in Western Europe. For women aged 35 - 39 years, our results are comparable to those of women living in the territory of India and Kenya. For women aged 40 - 44 years, our results were lower than those for women from the Western European and Chinese populations, close to the Indian and higher than Korean and Kenya populations, respectively. Our results for women of Bulgarian origin are also comparable to US Latina women at age 30, 35 and 40 ages. On the base on constructed a statistical model to predicting the decline in AMH levels at different ages, we found non-linear structure of AMH decline for the low AMH 3.5) the dependence of the decline of AMH on age was confirmed as linear. In conclusion, we evaluated the serum level of AMH in Bulgarian women and established age-specific AMH percentile reference values based on a large representative sample. We have developed a prognostic statistical model that can facilitate the application of AMH in clinical practice and the prediction of reproductive capacity and population health.展开更多
Background: Studies have shown a strong correlation between the growth of E2 in serum and estrone-3-glucuronide (E1-3G) in urine during ovarian stimulation. Thus, we developed theoretical models for using urinary E1-3...Background: Studies have shown a strong correlation between the growth of E2 in serum and estrone-3-glucuronide (E1-3G) in urine during ovarian stimulation. Thus, we developed theoretical models for using urinary E1-3G in ovarian stimulation and focused on their experimental verification and analysis. Methods: A prospective, observational pilot study was conducted involving 54 patients who underwent 54 cycles of ovarian stimulation. The goal was to establish the growth rate of urinary E1-3G during the course of stimulation and to determine the daily upper and lower limits of growth rates at which stimulation is appropriate and safe. Controlled ovarian stimulation was performed using two different stimulation protocols—an antagonist protocol in 25 cases and a progestin-primed ovarian stimulation protocol (PPOS) in 29 cases, with fixed doses of gonadotropins. From the second day of stimulation, patients self-measured their daily urine E1-3G levels at home using a portable analyzer. In parallel, a standard ultrasound follow-up protocol accompanied by a determination of E2, LH, and P levels was applied to optimally control stimulation. Results: The average daily growth rates in both groups were about 50%. The daily increase in E1-3G for the antagonist protocol ranged from 14% to 79%, while they were 28% to 79% for the PPOS protocol. Conclusion: This is the first study to analyze the dynamics of E1-3G in two different protocols and to estimate the limits of its increase during the entire course of the stimulation. The results confirm our theoretical model for the viability of using urinary E1-3G for monitoring ovarian stimulation.展开更多
Seafloor elongated depressions are indicators of gas seepage or slope instability. Here we report a sequence of slopeparallel elongated depressions that link to headwalls of sediment slides on upper slope. The depress...Seafloor elongated depressions are indicators of gas seepage or slope instability. Here we report a sequence of slopeparallel elongated depressions that link to headwalls of sediment slides on upper slope. The depressions of about 250 m in width and several kilometers in length are areas of focused gas discharge indicated by bubble-release into the water column and methane enriched pore waters. Sparker seismic profiles running perpendicular and parallel to the coast, show gas migration pathways and trapped gas underneath these depressions with bright spots and seismic blanking. The data indicate that upward gas migration is the initial reason for fracturing sedimentary layers. In the top sediment where two young stages of landslides can be detected, the slopeparallel sediment weakening lengthens and deepens the surficial fractures, creating the elongated depressions in the seafloor supported by sediment erosion due to slope-parallel water currents.展开更多
Objective To determine the sperm acrosome integrity of samples from infertile men with varicocele. Methods Forty-nine infertile men with varicocele were divided into three groups according to the grade of varicocele. ...Objective To determine the sperm acrosome integrity of samples from infertile men with varicocele. Methods Forty-nine infertile men with varicocele were divided into three groups according to the grade of varicocele. Group A （grade Ⅰ）, B （grade Ⅱ）, and C （grade Ⅲ） consisted of 15, 18, and 16 cases, respectively. Besides, 15 semen samples from normospermic donors were used as the control. The acrosome integrity of sperm was examined with fluorescein-labeled Pisum sativum agglutinin. Acrosomal ultrastructure was observed with transmission electron microscopy. Results In three varicocele groups, most samples had high sperm abnormal morphology rates. There were significant differences in acrosome integrity rates between each varicocele group and the control （P〈0.01）. Group C had the lowest acrosome integrity rate among the three groups. Ultrastructural observation showed that acrosome malformations revealed acrosomal membranes defects, swelling, hypoplasia, and dissolution of the matrix. Conclusions Infertile men with varicocele had low level of acrosome integrity. Severe varicocele for infertile men might be associated with severe acrosomal defects. Evaluating sperm acrosome should aid the understanding of the sperm structural state and benefit the treatment for infertile men.展开更多
We investigate sharp conditions for boundary and interior gradient estimates of continuous viscosity solutions to fully nonlinear, uniformly elliptic equations under Dirichlet boundary conditions. When these condition...We investigate sharp conditions for boundary and interior gradient estimates of continuous viscosity solutions to fully nonlinear, uniformly elliptic equations under Dirichlet boundary conditions. When these conditions are violated, there can be blow up of the gradient in the interior or on the boundary of the domain. In particular we de- rive sharp results on local and global Lipschitz continuity of continuous viscosity solutions under more general growth conditions than before. Lipschitz regularity near the boundary allows us to predict when the Dirichlet condition is satisfied in a classical and not just in a viscosity sense, where detachment can occur. Another consequence is this： if interior gra- dient blow up occurs, Perron-type solutions can in general become discontinuous, so that the Dirichlet problem can become unsolvable in the class of continuous viscosity solutions.展开更多
Objective To evaluate semen quality in infertile men with a history of unilateral cryptorchidism Methods Semen samples were obtained from 47 infertile men with a history of unilateral cryptorchidism. Semen analysis an...Objective To evaluate semen quality in infertile men with a history of unilateral cryptorchidism Methods Semen samples were obtained from 47 infertile men with a history of unilateral cryptorchidism. Semen analysis and membrane integrity including both eosin Y stain and hyo-osmotic swelling tests were performed using standard procedures. All men were divided into three groups according to their age at surgery of orchidopexy as follows： group A, 2-7 years （n=23）, group B, 8-13 years （n=14） and group C, 14-17years （n=10）. Results There was wide range for sperm count and motility for all the subjects studied. Majority of men had high percentage of abnormal sperm morphology. Among the three groups of men, group A and B had significantly higher sperm count, motility and membrane integrity than that of group C. Group C also had the highest frequency of oligoasthenoteraozoospermia （50%） than group A （17%） and group B （35%）. Conclusion Semen quality of men with a history of unilateral cryptorchidism appears to be related to their age of performing orchidopexy. Surgery at early age of childhood may improve spermatogenesis which results in better semen quality in adulthood.展开更多
Here we report electrospinning of Poly(dimethylsiloxane-b-vinyl pyrrolidone) (PDMS-b-PVP) based fibrous scaffold materials. The morphology, thermal properties, surface composition, hydrophilicity and fibers formation ...Here we report electrospinning of Poly(dimethylsiloxane-b-vinyl pyrrolidone) (PDMS-b-PVP) based fibrous scaffold materials. The morphology, thermal properties, surface composition, hydrophilicity and fibers formation with different PDMS and PVP chain lengths were determined by using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-ray photoelectron microscopy (XPS) and X-ray diffraction (RXD) water vapor uptake and water contact angle (WCA). The electrospinning parameters were controlled as well as fiber deposition area. The influence of polymer solution concentration on the morphology of electrospun fibers was also investigated. We checked out the applicability of the electrospun fibers for tissue engineering by the investigation of their capability to support fibroblast cell adhesion, cell growth and proliferation.展开更多
Analysis results of the average annual sea levels in the Caspian Sea obtained from ground and satellite observations, corresponding to solar activity characteristics, magnetic field data, and length of day are present...Analysis results of the average annual sea levels in the Caspian Sea obtained from ground and satellite observations, corresponding to solar activity characteristics, magnetic field data, and length of day are presented. Spectra of the indicated processes were investigated and their approximation models were also built. Previously assumed statistical relationships between space-geophysical processes and Caspian Sea level(CSL) changes were confirmed. A close connection was revealed between the low-frequency models of the solar and geomagnetic activity parameters and the CSL changes. Predictions extending into the next decades showed a high probability of an increase in the CSL and a decrease of the compared space-geophysical parameters.展开更多
The paper is a part of wider investigation related to the application of basic sciences to the sustainable development of society.It deals with the presentation of knowledge to the real estate(fast growing business)ab...The paper is a part of wider investigation related to the application of basic sciences to the sustainable development of society.It deals with the presentation of knowledge to the real estate(fast growing business)about the local natural and man-made hazards in the near vicinity of any structure(inhabitant,recreation area,land,etc.)and their influence to the social safety and human comfort of life.The structure,necessary information and knowledge base for visible or hidden hazards about a guide for the real estate business is included.An example of application the knowledge about seismic hazard and related phenomena simplified to be more available to the non-specialists(such as real estate agents and companies)targeted to Sofia(the largest urban center and capital of Bulgaria)can attract and improve the learning abilities of the real estate for the society’s sake.展开更多
Objective To investigate whether sperm immotility was caused by degeneration in the epididymis Methods Five patients with totally immotile sperm were selected in this study. Testicular biopsy was used to obtain tes...Objective To investigate whether sperm immotility was caused by degeneration in the epididymis Methods Five patients with totally immotile sperm were selected in this study. Testicular biopsy was used to obtain testicular sperm to evaluate sperm motility. The combined hypoosmotic swelling eosin Y exclusion test was carried out to determine the sperm head and tail membrane integrity for the ejaculated and the testicular sperm. The ultrastructure of ejaculated sperm was examined by transmission electron microscope. Results No motile sperm were found in the ejaculated semen samples from 5 patients, whereas 2% to 11% motile testicular sperm extracted from the testicular biopsy tissues were observed. The percentage of testicular sperm with intact head and tail membranes was higher than that of the ejaculated sperm (P<0.01). Ultrastructure of the ejaculated sperm showed marked degenerative features. Seminal plasma from patients did not influence the motility of normal donor sperm. Conclusion Sperm could undergo degenerative changes during transit through and /or storage in the epididymis, which led to lose sperm motility in these patients. Using motile testicular sperm would benefit the treatment for such cases.展开更多
文摘The present study aims to establish a relationship between serum AMH levels and age in a large group of women living in Bulgaria, as well as to establish reference age-specific AMH levels in women that would serve as an initial estimate of ovarian age. A total of 28,016 women on the territory of the Republic of Bulgaria were tested for serum AMH levels with a median age of 37.0 years (interquartile range 32.0 to 41.0). For women aged 20 - 29 years, the Bulgarian population has relatively high median levels of AMH, similar to women of Asian origin. For women aged 30 - 34 years, our results are comparable to those of women living in Western Europe. For women aged 35 - 39 years, our results are comparable to those of women living in the territory of India and Kenya. For women aged 40 - 44 years, our results were lower than those for women from the Western European and Chinese populations, close to the Indian and higher than Korean and Kenya populations, respectively. Our results for women of Bulgarian origin are also comparable to US Latina women at age 30, 35 and 40 ages. On the base on constructed a statistical model to predicting the decline in AMH levels at different ages, we found non-linear structure of AMH decline for the low AMH 3.5) the dependence of the decline of AMH on age was confirmed as linear. In conclusion, we evaluated the serum level of AMH in Bulgarian women and established age-specific AMH percentile reference values based on a large representative sample. We have developed a prognostic statistical model that can facilitate the application of AMH in clinical practice and the prediction of reproductive capacity and population health.
文摘Background: Studies have shown a strong correlation between the growth of E2 in serum and estrone-3-glucuronide (E1-3G) in urine during ovarian stimulation. Thus, we developed theoretical models for using urinary E1-3G in ovarian stimulation and focused on their experimental verification and analysis. Methods: A prospective, observational pilot study was conducted involving 54 patients who underwent 54 cycles of ovarian stimulation. The goal was to establish the growth rate of urinary E1-3G during the course of stimulation and to determine the daily upper and lower limits of growth rates at which stimulation is appropriate and safe. Controlled ovarian stimulation was performed using two different stimulation protocols—an antagonist protocol in 25 cases and a progestin-primed ovarian stimulation protocol (PPOS) in 29 cases, with fixed doses of gonadotropins. From the second day of stimulation, patients self-measured their daily urine E1-3G levels at home using a portable analyzer. In parallel, a standard ultrasound follow-up protocol accompanied by a determination of E2, LH, and P levels was applied to optimally control stimulation. Results: The average daily growth rates in both groups were about 50%. The daily increase in E1-3G for the antagonist protocol ranged from 14% to 79%, while they were 28% to 79% for the PPOS protocol. Conclusion: This is the first study to analyze the dynamics of E1-3G in two different protocols and to estimate the limits of its increase during the entire course of the stimulation. The results confirm our theoretical model for the viability of using urinary E1-3G for monitoring ovarian stimulation.
基金funded by the European project EUROFLEETS (Seventh Framework Programme, No. 228344)
文摘Seafloor elongated depressions are indicators of gas seepage or slope instability. Here we report a sequence of slopeparallel elongated depressions that link to headwalls of sediment slides on upper slope. The depressions of about 250 m in width and several kilometers in length are areas of focused gas discharge indicated by bubble-release into the water column and methane enriched pore waters. Sparker seismic profiles running perpendicular and parallel to the coast, show gas migration pathways and trapped gas underneath these depressions with bright spots and seismic blanking. The data indicate that upward gas migration is the initial reason for fracturing sedimentary layers. In the top sediment where two young stages of landslides can be detected, the slopeparallel sediment weakening lengthens and deepens the surficial fractures, creating the elongated depressions in the seafloor supported by sediment erosion due to slope-parallel water currents.
文摘Objective To determine the sperm acrosome integrity of samples from infertile men with varicocele. Methods Forty-nine infertile men with varicocele were divided into three groups according to the grade of varicocele. Group A （grade Ⅰ）, B （grade Ⅱ）, and C （grade Ⅲ） consisted of 15, 18, and 16 cases, respectively. Besides, 15 semen samples from normospermic donors were used as the control. The acrosome integrity of sperm was examined with fluorescein-labeled Pisum sativum agglutinin. Acrosomal ultrastructure was observed with transmission electron microscopy. Results In three varicocele groups, most samples had high sperm abnormal morphology rates. There were significant differences in acrosome integrity rates between each varicocele group and the control （P〈0.01）. Group C had the lowest acrosome integrity rate among the three groups. Ultrastructural observation showed that acrosome malformations revealed acrosomal membranes defects, swelling, hypoplasia, and dissolution of the matrix. Conclusions Infertile men with varicocele had low level of acrosome integrity. Severe varicocele for infertile men might be associated with severe acrosomal defects. Evaluating sperm acrosome should aid the understanding of the sperm structural state and benefit the treatment for infertile men.
基金financed by the Alexander von Humboldt Foundationcontinued in March 2009 at the Mathematisches Forschungsinstitut Oberwolfach in the "Research in Pairs"program
文摘We investigate sharp conditions for boundary and interior gradient estimates of continuous viscosity solutions to fully nonlinear, uniformly elliptic equations under Dirichlet boundary conditions. When these conditions are violated, there can be blow up of the gradient in the interior or on the boundary of the domain. In particular we de- rive sharp results on local and global Lipschitz continuity of continuous viscosity solutions under more general growth conditions than before. Lipschitz regularity near the boundary allows us to predict when the Dirichlet condition is satisfied in a classical and not just in a viscosity sense, where detachment can occur. Another consequence is this： if interior gra- dient blow up occurs, Perron-type solutions can in general become discontinuous, so that the Dirichlet problem can become unsolvable in the class of continuous viscosity solutions.
文摘Objective To evaluate semen quality in infertile men with a history of unilateral cryptorchidism Methods Semen samples were obtained from 47 infertile men with a history of unilateral cryptorchidism. Semen analysis and membrane integrity including both eosin Y stain and hyo-osmotic swelling tests were performed using standard procedures. All men were divided into three groups according to their age at surgery of orchidopexy as follows： group A, 2-7 years （n=23）, group B, 8-13 years （n=14） and group C, 14-17years （n=10）. Results There was wide range for sperm count and motility for all the subjects studied. Majority of men had high percentage of abnormal sperm morphology. Among the three groups of men, group A and B had significantly higher sperm count, motility and membrane integrity than that of group C. Group C also had the highest frequency of oligoasthenoteraozoospermia （50%） than group A （17%） and group B （35%）. Conclusion Semen quality of men with a history of unilateral cryptorchidism appears to be related to their age of performing orchidopexy. Surgery at early age of childhood may improve spermatogenesis which results in better semen quality in adulthood.
文摘Here we report electrospinning of Poly(dimethylsiloxane-b-vinyl pyrrolidone) (PDMS-b-PVP) based fibrous scaffold materials. The morphology, thermal properties, surface composition, hydrophilicity and fibers formation with different PDMS and PVP chain lengths were determined by using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-ray photoelectron microscopy (XPS) and X-ray diffraction (RXD) water vapor uptake and water contact angle (WCA). The electrospinning parameters were controlled as well as fiber deposition area. The influence of polymer solution concentration on the morphology of electrospun fibers was also investigated. We checked out the applicability of the electrospun fibers for tissue engineering by the investigation of their capability to support fibroblast cell adhesion, cell growth and proliferation.
文摘Analysis results of the average annual sea levels in the Caspian Sea obtained from ground and satellite observations, corresponding to solar activity characteristics, magnetic field data, and length of day are presented. Spectra of the indicated processes were investigated and their approximation models were also built. Previously assumed statistical relationships between space-geophysical processes and Caspian Sea level(CSL) changes were confirmed. A close connection was revealed between the low-frequency models of the solar and geomagnetic activity parameters and the CSL changes. Predictions extending into the next decades showed a high probability of an increase in the CSL and a decrease of the compared space-geophysical parameters.
文摘The paper is a part of wider investigation related to the application of basic sciences to the sustainable development of society.It deals with the presentation of knowledge to the real estate(fast growing business)about the local natural and man-made hazards in the near vicinity of any structure(inhabitant,recreation area,land,etc.)and their influence to the social safety and human comfort of life.The structure,necessary information and knowledge base for visible or hidden hazards about a guide for the real estate business is included.An example of application the knowledge about seismic hazard and related phenomena simplified to be more available to the non-specialists(such as real estate agents and companies)targeted to Sofia(the largest urban center and capital of Bulgaria)can attract and improve the learning abilities of the real estate for the society’s sake.
基金the Natural Science Foundation of Guangdong Province( No. 980 70 1 ) P.R.China
文摘Objective To investigate whether sperm immotility was caused by degeneration in the epididymis Methods Five patients with totally immotile sperm were selected in this study. Testicular biopsy was used to obtain testicular sperm to evaluate sperm motility. The combined hypoosmotic swelling eosin Y exclusion test was carried out to determine the sperm head and tail membrane integrity for the ejaculated and the testicular sperm. The ultrastructure of ejaculated sperm was examined by transmission electron microscope. Results No motile sperm were found in the ejaculated semen samples from 5 patients, whereas 2% to 11% motile testicular sperm extracted from the testicular biopsy tissues were observed. The percentage of testicular sperm with intact head and tail membranes was higher than that of the ejaculated sperm (P<0.01). Ultrastructure of the ejaculated sperm showed marked degenerative features. Seminal plasma from patients did not influence the motility of normal donor sperm. Conclusion Sperm could undergo degenerative changes during transit through and /or storage in the epididymis, which led to lose sperm motility in these patients. Using motile testicular sperm would benefit the treatment for such cases.
