Prediction of chlorophyll a concentration using HJ-1 satellite imagery for Xiangxi Bay in Three Gorges Reservoir

Since the impoundment of the Three Gorges Reservoir in 2003, algal blooms have frequently been observed in it. The chlorophyll a concentration is an important parameter for evaluating algal blooms. In this study, the chlorophyll a concentration in Xiangxi Bay, in the Three Gorges Reservoir, was predicted using HJ-1 satellite imagery. Several models were established based on a correlation analysis between in situ measurements of the chlorophyll a concentration and the values obtained from satellite images of the study area from January 2010 to December 2011. Chlorophyll a concentrations in Xiangxi Bay were predicted based on the established models. The results show that the maximum correlation is between the reflectance of the band combination of B4/（B2＋B3） and in situ measurements of chlorophyll a concentration. The root mean square errors of the predicted values using the linear and quadratic models are 18.49 mg/m3 and 18.52 mg/m3, respectively, and the average relative errors are 37.79% and 36.79%, respectively. The results provide a reference for water bloom prediction in typical tributaries of the Three Gorges Reservoir and contribute to large-scale remote sensing monitoring and water quality management.

Factors that Influence Professional Socialization in Nursing Students: A Multigroup Analysis

Background: Nursing professional socialization significantly influences the sustainable development of nursing students’ careers. This study aims to examine the factors that influence professional socialization in nursing students. Methods: This is a quantitative study of a sample of 108 nursing students (80 females and 28 males). The Simulation Learning Effectiveness Scale, Caring Assessment Report Evaluation Q-sort, Self-Reflection and Insight Scale, and Holistic Nursing Competence Scale were used to collect the data on the independent variables. The Team Skills Scale, Nursing Image as a Profession questionnaire, and Nursing Professional Commitment Scale were used to assess the level of students’ nursing professional socialization, which is an outcome construct variable. A multigroup analysis was used to examine the professional socialization research model. Results: The full model findings show that individual learning effectiveness had a significantly positive effect on nursing students’ caring behavior and on self-reflection and insight. In addition, caring behavior and self-reflection and insight had a significantly positive effect on nursing competence. Finally, nursing competence also had a significantly positive effect on nursing professional socialization. Overall, all independent variables were significant predictors of nursing professional socialization, explaining 36.7% of the variance in the integrated model of professional socialization. In addition, a permutation test revealed no differences in the two comparisons’ path coefficient estimates in the model (female vs. male). Conclusion: It is important to further strengthen nursing students’ self-learning effectiveness to promote their self-reflection and caring behavior. Increasing students’ nursing competence is a key factor in improving their professional socialization.

Nitrite inhalants use, sexual behaviors and HIV/syphilis infection among men who have sex with men in Chongqing, China

Background:Emerging evidence indicates nitrite inhalants have become increasingly prevalent among men who have sex with men(MSM).The present study aimed to describe the prevalence and correlates of nitrite inhalants use and its association with risky sexual behaviors and human immunodeficiency virus(HIV)/syphilis infection among MSM in Chongqing,a city in China where MSM were burdened with the highest pooled HIV prevalence in the country.Methods:This cross-sectional study was conducted in Chongqing between March 2019 and February 2020.Information of demographics,drug use,sexual behaviors and HIV testing was collected through an anonymous survey.Blood samples were drawn from each participant for the diagnoses of HIV and syphilis.Logistic regression analysis was performed to evaluate factors correlated with nitrite inhalants use and its relationship with risky sexual behaviors and HIV/syphilis infection.Results:Of the 1151 eligible participants,18.9%(218)reported use of at least one type of recreational drugs in the past 6 months,and nitrite inhalants were the most commonly used substance(17.7,95%confidence interval[CI]:15.6-20.2%).The proportions of participants reported engaging in group sex and practicing condomless internal ejaculation during anal sex in the past six months were 5.8%(95%CI:4.4-7.2%)and 41.7%(95%CI:38.7-44.7%),respectively.The general prevalence of HIV and syphilis infection among the enrolled MSM were 16.8%(95%CI:14.7-19.0%)and 12.6%(95%CI:10.7-14.4%),respectively.Factors positively associated with nitrite inhalants use included:age<25(adjusted odds ratio[aOR]=2.08,95%CI:1.10-3.94),monthly individual income≥CNY 3000(Chinese Yuan)(aOR=1.95,95%CI:1.18-3.22),preferring receptive anal intercourse(aOR=2.27,95%CI:1.34-3.84)and versatile anal intercourse(aOR=2.60,95%CI:1.64-4.13),age at first anal intercourse<18(aOR=1.79,95%CI:1.21-2.67),engaging in group sex in the past six months(aOR=9.34,95%CI:4.95-17.63),having multiple male sex partners in the past 6 months(aOR=2.32,95%CI:1.50-3.58),practicing CIE during anal sex in the past six months(aOR=1.71,95%CI:1.19-2.46),HIV infection(aOR=1.72,95%CI:1.11-2.66)and syphilis infection(aOR=1.98,95%CI:1.23-3.17).Conclusions:This study found that nitrite inhalants were the most commonly used recreational substance among MSM and nitrite inhalants use were associated with higher probability of HIV and syphilis infection.Therefore,increased attention and counselling should be given to nitrite inhalants-using MSM.

Inhibition of trehalase affects the trehalose and chitin metabolism pathways in Diaphorina citri(Hemiptera:Psyllidae)

The Asian citrus psyllid,Diaphorina citri is the principal vector of huanglongbing,which transmits Candidatus Liberibacter asiaticus.Trehalase is a key enzyme involved in trehalose hydrolysis and plays an important role in insect growth and development.The specific functions of this enzyme in D.citri have not been determined.In this study,three trehalase genes(DcTreJ-1,DcTrel-2,and DcTre2)were identified based on the D.citri genome database.Bioinformatic analysis showed that DcTrel-1 and DcTrel-2 are related to soluble trehalase,whereas DcTre2 is associated with membrane-bound trehalase.Spatiotemporal expression analysis indicated that DcTrel-1 and DcTrel-2 had the highest expression levels in the head and wing,respectively,and DcTre2 had high expression levels in the fat body.Furthermore,DcTrel-1 and DcTrel-2 expression levels were induced by 20-hydroxyecdysone and juvenile hormone III,but DcTre2 was unaffected.The expression levels of DcTrel-1,DcTrel-2,and DcTre2 were significantly up-regulated,which resulted in high mortality after treatment with validamycin.Trehalase activities and glucose contents were downregulated,but the trehalose content increased after treatment with validamycin.In addition,the expression levels of chitin metabolism-related genes significantly decreased at 24 and 48 h after treatment with validamycin.Furthermore,silencing of DcTrel-1,DcTrel-2,and DcTre2 reduced the expression levels of chitin metabolism-related genes and led to a malformed phenotype of D.citri.These results indicate that D.citri trehalase plays an essential role in regulating chitin metabolism and provides a new target for control of D.citri.

Related Factors of in vitro Fertilization and Embryo Transfer Patients with Complete Fertilization Failure

Objective To find the possible factors predicting fertilization failure of in vitro fertilization-embryo transfer （1VF-ET）. Methods The IVF-ET patients with complete fertilization failure （experimental group, n =32） were analyzed retrospectively. The patients whose oocytes retrieved at the same day and cultured on the same incubators with ≥ 50% fertilization rates were matched as the control （n=56）. Results The infertility duration, superovulation days, the rates of primary case, progesterone （P） level 〉3.12 nmol/L rate and rate of severe abnormal sperm （abnormal sperm rate 〉95%） in experimental group were significantly higher than those in the control （6.4 ±3.1 years, 12.6 ±2.2 d, 56%, 43%, 43% vs 4.6±2.9years, 11.6 ±% 1.3 d, 33%, 23%, 23%, respectively, P〈0.05）. Conclusion We should pay attention to these patients with primary infertility, longer infertility duration and superovulation days （〉6.4 years and 〉12.6 d） and having increased level of P on hCG injection day （〉3.12 nmol/L）, abnormal sperm rate 〉95% at the same time. They should be included in such patients at high risk of fertilization failure.

Enhanced thermoelectric performance of Cu_(2)SnSe_(3) via synergistic effects of Cd-doping and CuGaTe_(2) alloying

In this work,we show significantly enhanced thermoelectric performance in Cu_(2) SnSe_(3) via a synergistic effect of Cd-doping and CuGaTe_(2) alloying in the temperature range of 300-823 K.Both the electron and phonon transport properties can be simultaneously regulated by Cd doping at Sn site,leading to a higher quality factor.Meanwhile,a maximum figure of merit(zT) value of ~0.68 was obtained for Cu_(2) Sn_(0.93)Cd_(0.07)Se_(3) sample at823 K,which is about four times higher than that of the pristine sample(zT=0.18 at 773 K).Furthermore,Cu_(2) Sn_(0.93)Cd_(0.07)Se_(3) was alloyed with CuGaTe_(2) to reduce the lattice thermal conductivity in the high-temperature region.Consequently,a further enhanced zT value(0.77,823 K) was achieved in the(Cu_(2) Sn_(0.93)Cd_(0.07)Se_(3))_(0.94)(CuGaTe_(2))_(0.06) sample,with a high average zT(zT_(ave)) value of0.30 between 300 and 823 K.These results demonstrate that Cd-doping combined with CuGaTe2 alloying could be an effective method to enhance zT values of Cu_(2) SnSe_(3) based compounds.

Selective Short-term Fertilization Combined with Early Rescue ICSI: An Optimal Strategy for Patients at High Risk for Fertilization Failure

Objective To investigate clinical outcomes in patients who were at more precise criteria risks for fertilization failure and were treated with selective, short-term fertilization （oocytes and sperm co-incubated for 4 h） and early rescue intracytoplasmic sperm injection （ICSI）. Methods A retrospective analysis was performed on 2023 women undergoing assisted reproductive technology （ART）. They were assigned to 4 groups： short-term in vitro fertilization （short-term IVF,, group A, n=217）, regular IVF （oocytes and sperm coincubated overnight, group B, n=1475）, short-term IVF and early rescue ICSI （shortterm ICSI, group C, n=94）, and regular ICSI （group D, n=237）. Results In group A, 69.8% （217/311） achieved normal fertilization rates, and the complete fertilization failure rate （fertilization rate was 0%） was 12.9% （40/311）. But all of the fertilization failure oocytes got rescue ICSI. In group B, the complete fertilization failure rate was 1.1% （19/1 692）. The fertilization rate, 2 PN （pronucleus） rate, and i PN rate were significantly lower in group A than those in group B （70.9% vs 80.8%, 57.8% vs 66.3%, and 3.5% vs 6.2%, respectively）. No significant differences were observed in clinical pregnancy rates and birth defect rates between groups A and B. The fertilization rates in groups C and D did not significantly differ （77.9% vs 76.2%）, which was also true for birth defect rates. The clinical pregnancy rate of group C was higher than that of group D （51.2% vs 42.3%）, but this difference was not significant （P〉0. 05）.Conclusion These results suggested that selective, short-term fertilization can result in effective outcomes for patients who were at high risk for fertilization failure.

Impact of Blood Clot in Oocyte-Corona-Cumulus Complex during in vitro Fertilization and Embryo Transfer

Objective To study the impact of blood clots in the oocyte-corona-cumulus complexes （OCCC） during in vitro fertilization and embryo transfer （IVF-ET）.Methods The OCCCs were harvested from the patients undergoing long protocol ovarian hyperstimulation. The OCCCs with blood clots removed or not, were randomly grouped into A or B. The OCCCs without blood clots were group C （the control）.Results The patient＇s age, infertility duration, the average GN consumption, the average days of superovulation and an average number of harvested oocytes showed no significant difference in the 3 groups. The fertilization rate and 2PN rate in group A were the highest, which were 85.4% and 71.1%, respectively, followed by group C, which were 77.5% and 64.9%, respectively. The lowest fertilization rate and 2PN rate were in group B, 75.8% and 62.2%, respectively. Those in group A were significantly higher than those in groups B and C （P〈0.01）, while there was no significant difference between group B and group C. The implantation rates and pregnancy rates showed no significant difference in the 3 groups after transplantation, even if group A got the highest rate among the 3 groups. Conclusion Removing the blood clots in OCCC can improve the outcome of IVF-ET without increasing the cost and complexity of the operation.