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A total of 99 volatile organic compound(VOC) species were detected the Langfang development zones based on continuous monitoring using a ZF-PKU-1007 between August 25 and September 30, 2018. The concentrations, reactivity, and sources of VOCs were studied under different O 3 concentrations using compositional analysis. The results showed that the average VOCs concentration during the research period was(75.17±38.67)×10 -9 , and was(112.33±30.96)×10 -9 , (66.25±34.84)×10 -9 on pollution days and cleaning days, respectively(VOCs concentrations were 69.6% higher on pollution days). The contribution of VOCs species to the ozone formation potential(OFP) were ranked in the order aldehydes > aromatics > alkenes > alkanes. In the case of L ·OH , the main contributions were from aromatics(30.0%) and alkenes(25.8%) on pollution days, while the contribution from aromatic alkenes(29.8%) was a slightly higher than aromatics(28.0%) on cleaning days. By applying the positive matrix factorization(PMF) model, five major VOCs sources were extracted, namely vehicle emissions(34.4%), solvent usage and evaporation(31.7%), the petrochemical industry(15.7%), combustion(11.1%), and plant emissions(7.9%). The contributions of solvent usage and evaporation and plant emission sources on pollution days were 13.1% and 1.2% higher than on cleaning days, respectively, which was likely due to relatively higher temperatures on these days. Therefore, vehicle emissions and solvent usage and evaporation should be priorities in VOCs control strategies for the Langfang development zones between August to September.

Objective: To retrospectively analyze the incidence of chromosomal polymorphisms in prenatal cytogenetic diagnostic cases and the effect of the clinical manifestation of these fetuses., Materials and Methods: 490 fetuses with chromosomal polymorphisms among 9996 pregnant women who underwent prenatal cytogenetic diagnosis were included in this study and were set as group 1. Other 500 pregnant women, whose fetuses were with normal karyotypes, were randomly selected from the remaining pregnant women and set as group 2. Clinical information and outcomes and maternal serum screening results of group 1 were compared with group 2., Results: The frequency of fetal chromosomal polymorphism was 4.90% (490/9996). The most common variants observed were 1/9/16 qh± (2.27%, 227/9996), followed by inv(9) (0.90%, 90/9996). 94.62% (264/279) of fetal chromosomal variants were inherited from parents. No statistical difference was found in clinical information and outcomes and maternal serum screening results between group 1 and group 2., Conclusion: The fetus with chromosomal polymorphism has no impact on serum markers of second trimester screening and does not play an important role for the clinical outcome of the current pregnancy either, whether it is inherited from the parents or a de novo mutation., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest relevant to this article., (Copyright © 2020. Published by Elsevier B.V.)

The aims of this study were to demonstrate the clinical and cytogenetic results of amniocentesis (AS) cases in Northeast China, to compare the incidence of different kinds of chromosomal abnormalities, and to study the association between the detection rate of chromosomal abnormalities and different indications for prenatal diagnosis. Cytogenetic analysis was performed on long-term tissue cultures of 2500 second-trimester amniotic fluid samples. The most common indication for genetic AS was abnormal maternal serum-screening test (69.56%), followed by advanced maternal age (15.04%). Chromosomal abnormality was detected in 206 (8.24%) of the 2500 samples. The detection rate of abnormal karyotypes was 62.5% in the group in which one member of the couple was a carrier of a chromosome abnormality; in the group having a positive result from noninvasive prenatal testing, the frequency was 50%. To determine the origin of fetal chromosome abnormal karyotype, 45 fetuses were analyzed. Of these, 20 were found to be de novo abnormalities and 25 were familial. The frequency and proportion of abnormal karyotypes varied substantially across different maternal AS indications. Knowing the origin and type of chromosomal abnormality would help determine termination or continuation of the pregnancy.

The aim of this study was to evaluate the correlation between chromosomal polymorphisms and male infertility. The patients were diagnosed with azoospermia or oligospermiaby a semen analysis. Chromosomal analysis was performed on peripheral blood lymphocytes obtained from the patients, with standard G-banding and C-banding. Y chromosome microdeletions were detected by multiplex polymerase chain reaction (PCR) amplification. The parents of 35 polymorphic probands were also subjected to chromosomal analysis, and their detailed reproductive histories were surveyed. The frequency of autosomal polymorphisms did not differ significantly among the infertile patients and fertile control individuals. The frequency of the Yqh-variant increased with the decrease in sperm count; this appeared at a significantly higher frequency in the azoospermia group (57.2 vs 24.3 vs 0%). The results of PCR amplification indicated that 32.14% of the patients with Yqh ± had microdeletions in the Y chromosome. The parents of the probands with the same chromosomal polymorphisms as the probands (among the 35 recalled families) did not show any adverse reproductive history. We observed no significant correlations between autosomal polymorphisms and male infertility. However, we observed a significant increase in the frequency of Yqh- in the azoospermic patients. This may be attributed to Y chromosome microdeletions, although the association between Y chromosome microdeletions and Y chromosome variants remains to be elucidated.

The prevalence of Y chromosome microdeletions among azoospermic, severe oligozoospermic, moderate oligozoospermic, and mild oligozoospermic patients with varicocele-related and idiopathic infertility shows conflicting data in Asian countries. We aimed to detect this frequency in Northeast China, and investigated spermatogenic defects whether associated with varicocele or Y chromosome microdeletions. All samples underwent a thorough physical examination, semen analysis, and PCR analyses for Y chromosome microdeletions. We randomly selected 150 infertile non-obstructive azoospermic patients with left varicocele (Group 1), 150 idiopathic non-obstructive azoospermic infertility patients (Group 2), 150 infertile severe oligozoospermic patients with left varicocele (Group 3), 150 idiopathic severe oligozoospermic infertility patients (Group 4), 150 infertile moderate oligozoospermic patients with left varicocele (Group 5), 150 idiopathic moderate oligozoospermic infertility patients (Group 6), 150 infertile mild oligozoospermic patients with left varicocele (Group 7), 150 idiopathic mild oligozoospermic infertility patients (Group 8), and 60 healthy unrelated men with proven fertility were recruited as control subjects (Group 9). We observed that our samples from Northeastern China had a higher frequency of microdeletions among the non-obstructive azoospermic individuals with varicocele, as compared with other Asian countries. Furthermore, the spermatogenic defect is due to the underlying Y chromosome microdeletion, and not the varicocele itself. Although varicocele is not the cause of male infertility, it may be associated with male infertility in the Northeastern Chinese population.

Y chromosome microdeletions can cause male infertility and are classified as natural transmission and de novo mutations. To examine the source of these deletions in Chinese men and to provide a theoretical and laboratory basis for genetic counseling, patients from Northeast China with primary male infertility (N = 22) and their fathers were investigated. Karyotype analysis was performed on peripheral blood lymphocytes using standard G-banding. Multiplex polymerase chain reaction amplification using 18 specific sequence-tagged sites was selected to detect Y chromosome microdeletions. De novo mutations were observed in 17 father-son pairs, leading to a mutation rate of 77.27% (17/22), while the vertical transmission of Yq AZFc microdeletions was detected in 5 cases of the families investigated (29.41%, 5/17). There were no statistically significant differences between vertically transmitted and de novo mutations in men with AZFc deletions regarding age, testicular volume, and reproductive hormone levels. Most Y chromosome microdeletions in men from Northeast China are the result of de novo mutations via natural conception, and men with Yq AZFc deletions showed no clear differences between vertical transmission and de novo mutations.

Azoospermia factor (AZF) microdeletions are the most frequent genetic cause of male infertility after Klinefelter's syndrome. Although some assisted reproductive techniques such as intracytoplasmic sperm injection (ICSI) have been successfully introduced to clinical treatment for infertile males, the AZF microdeletions might be transmitted from infertile fathers to their male offspring during these procedures. Thus, it is important to carefully evaluate AZF microdeletions in infertile males before assisted reproductive techniques are performed. In this article, we aimed to investigate the frequencies of AZF microdeletions in 137 infertile males with azoospermia and severe oligozoospermia from Jilin province of China and analyse the relationship between the levels of reproductive hormones and AZF microdeletions. Result analysis showed that AZF microdeletions were present in 8 (8.70%) azoospermic males and 3 (6.67%) severely oligozoospermic males. The most frequent microdeletions were detected in the AZFc region, followed by AZFb + c, AZFb and AZFa. And there was no significant correlation between the AZF microdeletion and the levels of reproductive hormones. These findings reinforce the necessity of AZF microdeletion testing among infertile males prior to employment of assisted reproduction techniques in Jilin province of China., (© 2013 Blackwell Verlag GmbH.)

The subsequent reproductive outcomes in couples with a history of recurrent pregnancy loss (RPL) associated with chromosome abnormalities or polymorphisms are generally not reported in China. Many RPL carrier couples have decided not to have children. The present study recorded the subsequent delivery, miscarriage, and unpregnancy outcomes of 113 RPL carrier couples and 226 non-carrier couples, and compared differences in reproductive outcomes between couples with different types of chromosome abnormalities or polymorphisms and chromosome normal couples. Our results showed that couples with RPL associated with parental chromosome abnormalities or polymorphisms did not have significantly lower live birth rates than non-carrier couples in China. These results suggest the current guidance given to Chinese RPL couples.

Abstract This study constructed a technique effectiveness evaluation formula for table tennis players based on the relationship between the scoring rate and usage rate of techniques and established evaluation criteria through the examination of 224 matches of the world's top 35 players. It also built a competition performance formula with the score difference theory for the exploration of the correlation between player technique effectiveness and competition performance. The results showed the three indices - the technique effectiveness of the first and third strokes (TE₁,₃), the second and fourth strokes (TE₂,₄) and the after fourth strokes (TE>₄) - could help better evaluate the technique effectiveness of elite players. The comparative analysis of Chinese elite table tennis players and players from other countries and regions revealed that Chinese players as a whole were 'excellent' in all the examined techniques except in the male's 'first and third strokes'; while players from other countries and regions were overall 'general'. The case analysis of two of the world's top players further indicated that correlation analysis of technique effectiveness and competition performance could help identify the technique indices highly correlated with player competition performance.

The prevalence of microdeletions of azoospermia factor (AZF) among azoospermic Klinefelter's syndrome (KFS) patients shows conflicting data. We aimed to detect this frequency in a Northeast Chinese population, and to investigate the possible association between AZF microdeletions and KFS by comparison with previous conflicting reports. Eighty men affected with KFS and a random healthy control group comprising 60 fertile men and women were recruited. AZF microdeletions were detected by multiplex polymerase chain reaction using 9 specific sequence-tagged sites. Karyotype analyses were performed on peripheral blood lymphocytes using standard G-banding. Finally, azoospermia was confirmed in 77 men affected with KFS and no AZF microdeletions were found. Karyotype analysis revealed 1 patient with karyotype 47,XXY,inv (9) (p11, q13), and 2 with mosaic karyotypes (46,XX/47,XXY and 46,XY/47,XXY). All other patients had karyotype 47,XXY. Review of the literature showed that these results were similar to those of other regions of Northeast Asia, but differed from those obtained from Caucasian populations. Our results supported the proposal that AZF microdeletions and KFS result from separate genetic defects. The prevalence of AZF in azoospermic KFS patients varies among populations, and it might result from genetic drift or selective pressure. These results suggest that routine screening for classical AZF microdeletions among infertile azoospermic men with a 47,XXY karyotype might not be necessary in Northeast Chinese individuals. However, it remains imperative for patients considering assisted reproductive treatments, particularly for those with mosaic karyotypes.

Objective: To determine the frequencies and the characteristics of Y chromosome microdeletion in infertile men from northeastern China to perform appropriate therapeutic choices., Materials and Methods: The study included 1738 infertile men. Sperm concentration was measured according to standard methods and karyotype analysis was performed on peripheral blood lymphocytes with standard G-banding. Multiplex polymerase chain reaction amplification using 9 specific sequence-tagged sites were selected to detect Y chromosome microdeletions., Results: The data showed that the frequency of Y chromosome microdeletion was 8.57%. The most common microdeletion, among the azoospermia factor (AZF) regions, was detected in the AZFc region, followed by AZFb+c, AZFb, AZFa+b+c, AZFa, and AZFa+c. One-hundred seven patients with Y chromosome microdeletion developed azoospermia, 39 developed severe oligozoospermia (sperm concentration ≤5 × 10(6)/mL), and 3 developed moderate oligozoospermia (sperm concentration >5 × 10(6)/mL and ≤10 × 10(6)/mL). Karyotype analysis was available for 130 patients with Y chromosome microdeletion and abnormal karyotypes were found in 19 patients (14.6%). The most frequent abnormal karyotype was 46,X,Yqh-(n = 7)., Conclusion: In northeastern China, Y chromosome microdeletion diagnosis should be performed before the use of intracytoplasmic sperm injection in infertile men with sperm count ≤10 × 10(6)/mL, especially in men with azoospermia., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Purpose: To explore the prevalence and clinical features, especially the reproductive function, of 45,X mosaicism patients in northeast China., Methods: GTG-banding was performed on a series of 2,250 patients from our genetic counseling clinic. Each of these patients underwent a physical examination and was interviewed about their medical history and reproductive problems. Literature on 45,X mosaicism was accessed using PubMed and reviewed., Results: The prevalence of 45,X mosaicism in northeast China is 0.36 % (8/2250), and the mosaic karyotype of our study accounted for 61.54 % (8/13) of Turner syndrome cases. This is comparable with studies from Asia, Europe, South America and other regions. The affected patients showed genital abnormalities, abnormal pregnancy or infertility., Conclusion: 45,X mosaicism is commonly seen in the genetic counseling clinic. Extensive cytogenetic assessment may improve the detection rate in patients with congenital dysplasia, or history of abnormal pregnancy or infertility. Karyotyping plays a key role in prognosis and assisted reproduction or early surgical treatment.

Non-classical human leukocyte antigen (HLA)-DM plays an important and unique role in the processing and presentation of exogenous antigens. Polymorphisms of certain genes and frequency of alleles in populations may indicate susceptibility to certain diseases. In this study, the analysis of HLA-DMA and HLA-DMB gene polymorphisms and haplotypes in the Chinese Han population was conducted to obtain population genetic data. HLA-DM typing has been performed previously by other groups by polymerase chain reaction (PCR)-restriction fragment length polymorphism and PCR-sequence-specific oligonucleotide probe techniques. In this study, we established a TaqMan PCR typing method as an alternative to these techniques to survey the frequency of DMA and DMB alleles in the population. Genotyping was conducted in 1000 unrelated individuals of Han nationality in South and North China using TaqMan PCR typing. Four different DMA alleles and six different DMB alleles were detected. All loci met the Hardy-Weinberg equilibrium principle that both allele and genotype frequencies in a population remain constant. We found that the DMA*01:01 (69.35%) and DMB*01:01 (52.5%) alleles were more frequent in Chinese Hans. Analysis of the haplotypes for two loci of DMA and DMB showed that a highly significant positive linkage disequilibrium (LD) presented for DMA*01:01-DMB*01:02, DMA*01:01-DMB*01:03, DMA*01:01-DMB*01:04, DMA*01:02-DMB*01:01, DMA*01:02-DMB*01:05, DMA*01:03-DMB*01:07, and DMA*01:04-DMB*01:01 haplotypes. Analysis of haplotypes for four loci associated with antigen processing (DMA-DMB-TAP1-TAP2) showed a highly significant LD in DMA*01:01-DMB*01:04-TAP1*02:01:01-TAP2*01:02, DMA*01: 02-DMB*01:05-TAP1*01:01-TAP2*01:01, and DMA*01:01-DMB*01:03-TAP1* 04:01-TAP2*01:01 haplotypes. The comparison between the Chinese Han population and non-Chinese populations showed that no significant differences were found at the HLA-DMA locus in the Chinese Han population compared with people of German nationality, whereas significant differences presented when compared with Turkish, American Caucasian, Japanese, French, and Italian nationalities. However, at the HLA-DMB locus, highly significant differences presented in the Chinese Han population compared with Germans and Italians. This study lays the foundations for further disease association analyses., (© 2012 John Wiley & Sons A/S.)

Purposes: To detect the frequency and types of chromosomal anomalies with non-obstructive azoospermia and severe oligozoospermia in Northeast China, and to compare the frequencies with other regions of China and the world. To investigate the general characteristics of this population., Methods: Eighty-one men with non-obstructive azoospermia and 54 men with severe oligozoospermia were recruited. Karyotype analyses were performed on peripheral blood lymphocytes using standard G-banding. Measurements of follicle-stimulating hormone, testosterone, prolactin, and inhibin B were obtained., Results: The frequency of chromosomal anomalies for patients with non-obstructive azoospermia (17.28%) was comparable with studies from Europe, Africa, Asia, and other regions of China. However, the frequency for patients with severe oligozoospermia (9.26%) was slightly higher than reported from other Asian countries. The infertile men were more likely than the fertile to smoke and consume alcohol, and to have significantly lower levels of inhibin B., Conclusions: For infertile men in Northeast China, chromosome analysis is a necessary part of routine genetic testing, and the contributing effects of high smoking and alcohol consumption rates of this population should be discussed during genetic counseling.

Objective: To determine characteristics of classical and partial deletions of the Y chromosome azoospermia factor (AZF) region transmitted from father to son by natural fertilization., Methods: Patients from northeastern China with primary male infertility (n = 10) and their fathers were investigated. Healthy fertile men and women were recruited as positive and negative controls, respectively. The Y chromosome microdeletions were detected by polymerase chain reaction. Serum concentrations of reproductive hormones were determined by electrochemiluminescence immunoassay and enzyme-linked immunosorbent assay., Results: Expansions of microdeletions were observed in seven father–son pairs; de novo microdeletions were found in the remaining three father–son pairs. The Y chromosome microdeletions were larger in sons than in their fathers. Patients with infertility had significantly higher levels of follicle stimulating hormone and lower levels of inhibin B than fertile men., Conclusions: The Y chromosome microdeletions were transmitted from father to son via natural transmission. These microdeletions may expand during transmission or arise de novo, possibly resulting in reduced fertility.

Carrying Capacity of the Environment (CCE) provides a useful measure of the sustainable development of a region. Approaches that use integrated assessment instead of measurement can lead to misinterpretation of sustainable development because of confusion between Environmental Stress (ES) indexes and CCE indexes, and the selection of over-simple linear plus models. The present paper proposes a comprehensive measurement system for CCE which comprises models of natural resources capacity, environmental assimilative capacity, ecosystem services capacity, and society supporting capacity. The corresponding measurable indexes are designed to assess CCE using a carrying capacity surplus ratio model and a vector of surplus ratio of carrying capacity model. The former aims at direct comparison of ES and CCE based on the values of basic indexes, and the latter uses a Euclidean vector to assess CCE states. The measurement and assessment approaches are applicable to Strategic Environmental Assessment (SEA) and environmental planning and management. A case study is presented for Ningbo, China, whereby all the basic indexes of ECC are measured and the CCE states assessed for 2005 and 2010., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The objective of this study was to test the validity, in the Chinese population, of the Lifting The Burden diagnostic questionnaire for the purpose of a population-based survey of the burden of headache in China. From all regions of China, a population-based sample of 417 respondents had completed the structured questionnaire in a door-to-door survey conducted by neurologists from local hospitals calling unannounced. They were contacted for re-interview by telephone by headache specialists who were unaware of the questionnaire diagnoses. A screening question ascertained whether headache had occurred in the last year. If they had, the specialists applied their expertise and ICHD-II diagnostic criteria to make independent diagnoses which, as the gold standard, were later compared with the questionnaire diagnoses. There were 18 refusals; 399 interviews were conducted in 202 women and 197 men aged 18-65 years (mean age 44.4±12.6 years). In comparison to the specialists' diagnoses, the sensitivity, specificity, positive predictive value, negative predictive value and Cohen's kappa (95% CI) of the questionnaire for the diagnosis of migraine were 0.83, 0.99, 0.83, 0.99 and 0.82 (0.71-0.93), respectively; for the diagnosis of tension-type headache (TTH), they were 0.51, 0.99, 0.86, 0.92 and 0.59 (0.46-0.72), respectively. In conclusion, the questionnaire was accurate and reliable in diagnosing migraine (agreement level excellent), less so, but adequate, for TTH (sensitivity relatively low, false negative rate relatively high and agreement level fair to good). The non-specific features of TTH do not lend themselves well to diagnosis by questionnaire., (© The Author(s) 2011. This article is published with open access at Springerlink.com)

This study investigated the effects of Ureaplasma urealyticum infection and raised seminal leucocyte levels on sperm morphology in 967 infertile males and 201 fertile healthy volunteers. U. urealyticum infection led to a significant decrease in the percentage of morphologically normal sperm in infertile males. There was a clear correlation between U. urealyticum infection, raised seminal leucocytes and abnormal sperm morphology. The percentage of morphologically normal sperm was significantly lower in U. urealyticum-positive than U. urealyticum-negative infertile males or fertile controls. The percentage of morphologically normal sperm was lowest in U. urealyticum-positive males with raised seminal leucocytes. Previous studies have found raised seminal leucocyte levels to be associated with reactive oxygen species. The authors suggest that oxidative stress contributes to the effects of U. urealyticum on sperm morphology. In conclusion, U. urealyticum infection can negatively affect sperm morphology and this study provided two possible mechanistic explanations.

Purposes: To investigate the frequencies of AZF microdeletions and chromosomal abnormalities in infertile men from Northeastern China. Moreover, to compare the prevalence of these abnormalities with other countries and regions in the world., Methods: 305 infertile men were enrolled. A complete semen analysis and reproductive hormones were measured according to standard methods. Multiplex polymerase chain reaction (PCR) amplification using nine specific sequence-tagged sites (STS) were used to detect AZF microdeletions. Karyotype analyses were performed on peripheral blood lymphocytes with standard G-banding., Results: Of the 305 infertile men, 28 (9.2%) had AZF microdeletions and 26 (8.5%) had chromosomal abnormalities. The most frequent microdeletions were in the AZFc+d, followed by AZFc, AZFb+c+d and AZFa. A total of 19 patients (82.6%) had Klinefelter's syndrome (47, XXY) in the azoospermic group., Conclusions: The freqencies of AZF microdeletions and chromosomal abnormalities in infertile men from Northeastern China were comparable with infertile men from other countries and regions. However, there was a slightly higher prevalence rate of AZF microdeletions in oligozoospermic patients than reported in previous studies.

Aim: To develop a method for assessing sperm function by measuring released acrosin activity during the acrosome reaction (AR)., Methods: Human semen samples were obtained from 24 healthy donors with proven fertility after 3-7 days of sexual abstinence. After collection, samples were liquefied for 30 min at room temperature. Standard semen parameters were evaluated according to World Health Organization (WHO) criteria. Calcium ionophore A23187 and progesterone (P4) were used to stimulate the sperm to undergo AR. After treatment, sperm were incubated with the supravital dye Hoechst33258, fixed in a glutaraldehyde-phosphate-buffered saline solution, and the acrosomal status was determined by fluorescence microscopy with fluorescein isothiocyanate-labeled Pisum sativum agglutinin (FITC-PSA). The percentage of sperm undergoing AR (AR%) was compared to sperm acrosin activities as assessed by spectrocolorimetry. The correlation between AR% and acrosin activity was determined by statistical analysis., Results: The AR% and released acrosin activity were both markedly increased with A23187 and P4 stimulation. Sperm motility and viability were significantly higher after stimulation with P4 versus stimulation with A23187 (P < 0.001). There was a significant positive correlation between released acrosin activity and AR% determined by FITC-PSA staining (r=0.916, P < 0.001)., Conclusion: Spectrocolorimetric measurement of released acrosin activity might serve as a reasonable alternative method to evaluate AR.

A survey of the prevalence of smoking in middle school students aged 13-21 years in Harbin city, China, was undertaken in the Spring of 1988. A random sample of 4712 students was selected using proportional stratified clustering. A self-administered confidential questionnaire relating to smoking habits and certain family and school factors was administered. The results showed that 1.29% of the students (2.21% boys and 0.38% girls) smoked regularly, 5.62% (10.52% boys and 0.76% girls) were light smokers and 13.77% (24.29% boys and 2.92% girls) smoked only occasionally. Smoking habits were related to the type of school and to age, there being a higher proportion of smoking in senior grade students. Students were significantly more likely to smoke if they were male and if their siblings smoked. Prevalence of regular smoking was not related to parental occupation or family income. It is suggested that anti-smoking education in the school curriculum should be directed towards students in middle school.