A method for determining the optimum supporting opportunity of roadway based on energy dissipation.

The time and space of the support structure applying is related to the overall stability of the roadway after excavation directly. Designed twenty-four groups of roadway support schemes with time and space dimensions, and studied the stability characteristics of roadway in different schemes by using Fast Lagrangian Analysis of Continua in Three Dimensions. The main conclusions are as follows: the influence of energy dissipation (time) and support position (space) on the stability of the roadway is not a linear relationship, and supporting at the appropriate opportunity can be beneficial. Established the "displacement-dissipation energy" curve, founding that there is an obvious "jump" phenomenon in the dissipation energy of surrounding rock during the process of gradually increasing displacement. A novel method for determining the optimum supporting opportunity of roadway based on energy dissipation was proposed, based on the above finding. This study can provide an original idea for the determination of roadway supporting opportunity.

Environmental oestrogens disrupt testicular descent and damage male reproductive health: Mechanistic insight.

Environmental oestrogens (EEs) as environmental pollutants have been paid much attention due to their impact on congenital malformation of male genitourinary system. Exposure to EEs for prolonged time could hinder testicular descent and cause testicular dysgenesis syndrome. Therefore, it is urgent to understand the mechanisms by which EEs exposure disrupt testicular descent. In this review, we summarize recent advances in our understanding of the process of testicular descent, which is regulated by intricate cellular and molecular networks. Increasing numbers of the components of these networks such as CSL and INSL3 are being identified, highlighting that testicular descent is a highly orchestrated process that is essential to human reproduction and survival. The exposure to EEs would lead to the imbalanced regulation of the networks and cause testicular dysgenesis syndrome such as cryptorchidism, hypospadias, hypogonadism, poor semen quality and testicular cancer. Fortunately, the identification of the components of these networks provides us the opportunity to prevent and treat EEs induced male reproductive dysfunction. The pathways that play an important role in the regulation of testicular descent are promising targets for the treatment of testicular dysgenesis syndrome.

Intestinal obstruction caused by mesodiverticular band in children: a cohort study.

OBJECTIVE: To explore clinical characteristics, pathogenesis, diagnosis and treatment of intestinal obstruction due to mesodiverticular band (MDB) in children in a single center in China. METHODS: The clinical data of 20 children with acute intestinal obstruction due to MDB between 1998 and 2020 were retrospectively analyzed. RESULTS: The male-to-female ratio was 14:6 in 20 cases. Except one case of 7-month pregnant stillbirth, the cases were aged from 7 days to 14 years, at the median age of 4.31 years. The common symptoms were vomiting, abdominal pain and/or abdominal distension. About 40% (8/20) of patients had both MDB and Meckel's Diverticulum (MD), while 60% (12/20) of patients had MDB only. Only one case died because of total colonic aganglionosis, while other children recovered after surgery treatment. MDB led to the strangulation of necrotic bowel in six cases, intestinal perforation in one case, and intestinal rupture in one case. Pathologic examination showed thick-walled arteries and or thick venous vascular structures in the cord. All cases had no complications during 1-year follow-up. CONCLUSION: MDB results from the remnant of vitelline vessel, and often causes acute intestinal obstruction without special clinical symptoms. Unexplained abdominal pain and distension without surgery history should be paid attention, especially for strangulated intestinal obstruction. Timely surgical exploration is beneficial to avoid intestinal necrosis or even sudden death, and the pathological examination is important for the diagnosis.

Teacher emotion and pedagogical decision-making in ESP teaching in a Chinese University.

Teacher emotion has become an important issue in English language teaching as it is a crucial construct in understanding teachers' responses to institutional policies. The study explored teachers' emotion labor and its impact on teachers' pedagogical decision-making in English for Specific Purposes (ESP) teaching in a university of Traditional Chinese Medicine (TCM) in China. Drawing on a poststructural perspective, the study examined data from two rounds of semi-structured interviews, policy documents and teaching artifacts. The analysis of data revealed that the major emotion labor facing the participants revolved around students' disengagement in class. Teachers experienced mixed feelings of anticipation, disappointment, anger, and empathy toward students and distanced themselves from institutional feeling rules enforcing objective assessment of students' performance and punishing students for lack of engagement in class. The study found that teacher emotion labor served as the site for their pedagogical modifications. ESP teachers' beliefs in the importance of attending to students' needs become a powerful discourse in supporting teachers to strategically subvert institutional feeling rules and critically reflect on the dysfunctions of curriculum, orienting teachers' agentic actions in modifying pedagogical practices. We thus underscore this empowering discourse as the bridge to connect teachers' policy negotiation and their actual classroom practices. We also highlight teachers' pedagogical decision-making as a process of the interactions of teacher emotion, teachers' reflexive practices, and power relations. The study ended by suggesting more longitudinal research where teachers' beliefs as previously appropriated discourses could be examined comprehensively as they were both the construct of emotion labor and the potential subverting power in supporting teachers' pedagogical decision-making in policy negotiation.

Recent Progress in Metal-Organic Framework Based Fluorescent Sensors for Hazardous Materials Detection.

Population growth and industrial development have exacerbated environmental pollution of both land and aquatic environments with toxic and harmful materials. Luminescence-based chemical sensors crafted for specific hazardous substances operate on host-guest interactions, leading to the detection of target molecules down to the nanomolar range. Particularly, the luminescence-based sensors constructed on the basis of metal-organic frameworks (MOFs) are of increasing interest, as they can not only compensate for the shortcomings of traditional detection techniques, but also can provide more sensitive detection for analytes. Recent years have seen MOFs-based fluorescent sensors show outstanding advantages in the field of hazardous substance identification and detection. Here, we critically discuss the application of MOFs for the detection of a broad scope of hazardous substances, including hazardous gases, heavy metal ions, radioactive ions, antibiotics, pesticides, nitro-explosives, and some harmful solvents as well as luminous and sensing mechanisms of MOF-based fluorescent sensors. The outlook and several crucial issues of this area are also discussed, with the expectation that it may help arouse widespread attention on exploring fluorescent MOFs (LMOFs) in potential sensing applications.

A novel mutation of the RPGR gene in a Chinese X-linked retinitis pigmentosa family and possible involvement of X-chromosome inactivation.

OBJECTIVES: The objective of this study is to investigate the molecular mechanisms and genotype-phenotype correlations of a Chinese family with X-linked retinitis pigmentosa (XLRP). METHODS: A four-generation family with a total of 41 individuals including 7 affected males was recruited. All subjects in this pedigree underwent a complete ophthalmic examination. Targeted capture and next-generation sequencing were performed on the proband using a multigene panel containing 57 known causative genes of retinitis pigmentosa (RP), including RP1, RP2, RPGR, RHO, PRPH2, CRB1 among others. All variants were verified in the remaining family members by polymerase chain reaction amplification and Sanger sequencing. Blood DNA was used for X-chromosome inactivation analysis in female carriers. RESULTS: All the affected individuals were diagnosed with RP. The affected males showed symptoms from the first decade, while the female carriers had onset in the second decade or later. A frameshift mutation c.345_348delTGAA in the RPGR gene was identified in all affected males and female carriers. By XCI analysis, we found that there was little correlation between their phenotype and the methylation status of their X chromosomes. CONCLUSIONS: A novel mutation c.345_348delTGAA of the RPGR gene was identified, expanding the spectrum of RPGR mutations causing XLRP. In this pedigree, the phenotype extended to female carriers, in whom RP was milder and its onset delayed compared to hemizygous males. Although lack of strong correlation between X-inactivation and the severity of the disease, the milder, variable effects in female carriers still could reflect X-inactivation patterns in the retina of each individual.

scAAV2-Mediated C3 Transferase Gene Therapy in a Rat Model with Retinal Ischemia/Reperfusion Injuries.

Glaucoma is characterized by retinal ganglion cell (RGC) death and axonal loss. Therefore, neuroprotection is important in treating glaucoma. In this study, we explored whether exoenzyme C3 transferase (C3)-based gene therapy could protect retinas in an ischemia/reperfusion (I/R) injury rat model. Self-complementary adeno-associated virus 2 (scAAV2) vectors encoding either C3 protein (scAAV2-C3) or enhanced green fluorescence protein (scAAV2-EGFP) were intravitreally delivered into both eyes of rats, and I/R models (acute ocular hypertension) were made in one eye of each rat at day 7 after the injection. The rats were divided into six groups: scAAV2-C3, scAAV2-C3 with I/R, scAAV2-EGFP, scAAV2-EGFP with I/R, blank control, and blank control with I/R. TUNEL (terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate nick end labeling), immunohistochemistry of cleaved caspase-3, NeuN and Brn-3a, and H&E staining were used to detect apoptotic cells and other changes in the retina. The results showed that scAAV2-C3 significantly reduced the number of apoptotic RGCs and decreased cell loss in the ganglion cell layer after I/R injury, and the I/R-injured retinas treated with scAAV2-C3 were the thickest in all I/R groups. These results suggest that scAAV2-mediated C3 gene therapy is able to protect the rat retina from I/R injury and has potential in the treatment of glaucoma in the future.

Gas chromatography-mass spectrometry based serum metabolic analysis for premature infants and the relationship with necrotizing enterocolitis: a cross-sectional study.

BACKGROUND: Preterm birth and feeding are the most important pathogenic factors of neonatal necrotizing enterocolitis (NEC). Metabonomic has been widely used in the diagnosis and treatment of other diseases, but there is no research on the related diseases of premature infants. Compared with full-term infants, the metabolism of preterm infants has its own specificity, so it can easily lead to NEC and other digestive tract inflammatory diseases. Metabonomic may be applied to the diagnosis of preterm related diseases, such as NEC. METHODS: The model was established with premature infant serum samples from 19 premature infants in our hospital, which was compared with the full-term infant control group. Serum was analyzed by gas chromatography-mass spectrometry (GC-MS), coupled with the analysis of serum metabolic characteristics. The variable important in projection, P value and Pearson correlation coefficient of samples were analyzed by using SIMCA, SPSS and other multivariate statistical analysis software. RESULTS: Compared to the term infants, premature infants had significantly higher levels of luteolin, and lower levels of xylose, O-succinyl-L-homoserine and lauric acid in the serum. There were some correlations among several different metabolites and clinically related indices (albumin, total bilirubin) for premature birth related diseases. CONCLUSIONS: There are metabolic alterations in the serum of premature infants, which make contribution to the diagnosis of NEC.

The role of stressful life events and the Big Five personality traits in adolescent trajectories of problematic Internet use.

Cross-sectional studies have shown that both stressors and personality vulnerability are risk factors for adolescent problematic Internet use (PIU). However, little is known about how both categories of factors in combination may contribute to the longitudinal development of PIU among adolescents. The aims of this study were to document the developmental pattern of PIU among adolescents and to examine how stressful life events and the Big Five personality traits jointly affect the development of PIU. We tested three competing models: the additive, diathesis-stress, and social push models. A total of 1,365 adolescents participated in a 3-year longitudinal study. Hierarchical linear modeling indicated that PIU among adolescents increased over the 3-year period. After controlling for demographics and the Big Five personality traits, stressful life events (a time-varying predictor) were positively correlated with the initial level of, and the rate of change in, PIU. After controlling for demographics and stressful life events, four of the time-invariant Big Five personality dimensions had a significant effect on the initial level of PIU. Low Agreeableness, low Conscientiousness, high Openness, and high Neuroticism were positively associated with high initial PIU. In addition, Extraversion was negatively associated with and Conscientiousness was positively associated with the rate of change in PIU. The interaction effect between the personality and stressors was not significant. Therefore, the data provided support for the additive model, indicating that stressful life events and personality dimensions each make a unique contribution to PIU and that both should be considered in the prevention of adolescent PIU. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

[Serum metabolomics of preterm and full-term infants based on gas chromatography-mass spectrometry].

OBJECTIVE: To study the features of serum metabolites in preterm infants based on gas chromatography-mass spectrometry (GC-MS), and to find differentially expressed metabolites in the serum of preterm infants. METHODS: Serum samples were collected from 19 preterm infants and 20 full-term infants before feeding. GC-MS was used to measure metabolic profiles, and the metabolic features of 397 serum metabolites in preterm infants were analyzed. RESULTS: There was a significant difference in serum metabolic features between the preterm and full-term infants before feeding. There were significant differences between the full-term and preterm infants in the levels of metabolites such as O-phosphonothreonine, digicitrin, tannic acid, and fructose-1,6-diphosphate (P<0.01), suggesting that the above differentially expressed metabolites were highly differentiated between the preterm and full-term infants. Most differentially expressed metabolites were involved in the metabolic pathways such as ABC transporters, ß-alanine and pyrimidines and were correlated with some clinical parameters (albumin and total bilirubin) (P<0.05). CONCLUSIONS: There is a significant difference in serum metabolites between preterm and full-term infants before feeding. Metabolomics plays an important role in improving metabolic disorders and exploring metabolism-related diseases in preterm infants.

Tauroursodeoxycholic acid enhances the development of porcine embryos derived from in vitro-matured oocytes and evaporatively dried spermatozoa.

Evaporative drying (ED) is an alternative technique for long-term preservation of mammalian sperm, which does not require liquid nitrogen or freeze-drying equipment, but offers advantages for storage and shipping at ambient temperature and low cost. However, the development of zygotes generated from these sperms was poor. Here, we demonstrated that the supplementation of tauroursodeoxycholic acid (TUDCA), an endogenous bile acid, during embryo culture improved the developmental competency of embryos derived from in vitro matured pig oocytes injected intracytoplasmically with boar ED spermatozoa by reducing the production of reactive oxygen species, the DNA degradation and fragmentation, and the expression of apoptosis-related gene Bax and Bak, and by increasing the transcription of anti-apoptosis gene Bcl-XL and Bcl-2. Furthermore, TUDCA treatment promoted the blastocyst quality manifested by the total cell numbers and the ratio of inner cell mass. Taken together, our data suggest that evaporative drying would be a potentially useful method for the routine preservation of boar sperm in combination with further optimization of subsequently embryo culture conditions.

Dietary copper supplementation improves pelt characteristics of female silver fox (Vulpes fulva) during the winter fur-growing season.

Copper has an essential role in normal fur pigmentation and fur quality. This study evaluated the effects of cupric citrate (CuCit) supplementation on growth, nutrients metabolism and pelt characteristics of the female silver fox (Vulpes fulva). Fifty age-matched female silver foxes with similar body weights were randomly divided into five dietary groups for 58 days during the winter fur-growing season. The basal diet contained 4.92 mg/kg copper. Groups I-V were supplemented with 6, 30, 60, 90 or 150 mg Cu from CuCit per 1 kg dry matter basal diet. Serum alkaline phosphatase activity was significantly higher (P<0.05) in those fed 90 mg/kg Cu than those fed 150 mg/kg Cu. Pelt total thickness was significantly higher (P<0.05) in those fed 30 mg/kg Cu than foxes fed 6 mg/kg Cu supplemented diet, but were similar to the other groups. Length of guard hair was significantly lower (P<0.05) in those fed 90 mg/kg Cu than fed 6 mg/kg Cu and 30 mg/kg Cu, but were similar to the other groups. Length of underhair was significantly higher (P<0.05) in those fed 6 mg/kg Cu than those fed 90 mg/kg Cu, but was similar to the other groups. Considering decreasing environmental contamination and improving pelt performance, supplementing 30 mg/kg Cu from CuCit (actual copper 35 mg/kg dry matter) is appropriate for female silver fox.

[Expression and functional analysis of CRT-E2-EGFP fusion protein in B16 cells].

AIM: To detect the expression of the Calreticulin and HPV E2 Fusion Protein in B16, and study the effects on proliferation and apoptosis of B16 cell lines in vivo. METHODS: To construct eukaryotic fluoresce expression vector pEGFP-CRT-E2, pEGFP-CRT and pEGFP-E2. Then the recombinant plasmids were transfected into B16 cells by Lipofectamine 2000. The expression of proteins was detected by Western blot. The location of different GFP fusion proteins in B16 was tested by inverted fluoresce microscope. Flow cytometry was applied to detect the effects of fusion proteins on the growing of B16 and then the apoptosis effects of B16 induced by different proteins were observed. RESULTS: The correctly constructed recombinant plasmid pEGFP-CRT-E2 and the expression of CRT-E2 gene could be detected in B16 cells. Apoptosis of B16 cells could be detected after the transient transfection. Meanwhile, the apoptosis rate of B16 cells transfected by pEGFP-CRT-E2 was much higher than that of control cells. And cell cycle G1/G0 arrest was also found (P<0.01). CONCLUSION: The eukaryotic expression plasmid pEGFP-CRT-E2 is successfully constructed and it could correctly express the fusion protein in B16 cells. And the B16 cells transfected by plasmid pEGFP-CRT-E2 could induce apoptosis.

Determination of phenolic preservatives in gelatin and vacant capsules for medicine use by ion-suppression reversed-phase high performance liquid chromatography.

A reliable method for the simultaneous determination of phenolic preservatives parahydroxybenzoic acid, methyl, ethyl, propyl, butyl and pentyl parahydroxybenzoates in gelatin and vacant capsules for medical use has been developed by ion-suppression reversed-phase high performance liquid chromatography. Separation was carried out on a Kromasil C(18) column by isocratic elution using methanol-perchloric acid (pH 2.0; 10 mM) (60:40, v/v) at a flow-rate of 1.0 ml min(-1), and detection by UV absorbance at a wavelength of 254 nm. This method has been successfully applied to the routine analyses of these preservatives in the real samples.