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Based on the processes and characteristics of secondary electron emission and the formula for the yield due to primary electrons hitting on semiconductors and insulators, the universal formula for maximum yield due to primary electrons hitting on semiconductors and insulators was deduced, where is the maximum ratio of the number of secondary electrons produced by primary electrons to the number of primary electrons. On the basis of the formulae for primary range in different energy ranges of , characteristics of secondary electron emission and the deduced universal formula for , the formulae for in different energy ranges of were deduced, where is the primary incident energy at which secondary electron yields from semiconductors and insulators, , are maximized to maximum secondary electron yields from semiconductors and insulators, ; and is the maximum ratio of the number of total secondary electrons produced by primary electrons and backscattered electrons to the number of primary electrons. According to the deduced formulae for , the relationship among , and high-energy back-scattering coefficient , the formulae for parameters of and the experimental data as well as the formulae for in different energy ranges of as a function of , , and were deduced, where and are the original electron affinity and the width of forbidden band, respectively. The scattering of was analyzed, and calculated values were compared with the values measured experimentally. It was concluded that the deduced formulae for were found to be universal for . [ABSTRACT FROM AUTHOR]

Beta toxin (CPB) is a lethal toxin and plays a key role in enterotoxemia of ruminants caused by Clostridium perfringens type C strain. The existing vaccines based on crude CPB need time-consuming detoxification and difficult quality control steps. In this study, we synthesized the rCPB m4 of C. perfringens type C strain and small ubiquitin-like modifier (SUMO)-tag CPB m4 (rSUMO-CPB m4 ) by introducing four amino acid substitutions: R212E, Y266A, L268G, and W275A. Compared with rCPB m4 , rSUMO-CPB m4 was expressed with higher solubility in Escherichia coli BL21 (DE3). Neither rCPB m4 nor rSUMO-CPB m4 was lethal to mice. Although rCPB m4 and rSUMO-CPB m4 were reactogenic with polyclonal antibodies against crude CPB, rabbits vaccinated with rSUMO-CPB m4 developed significant levels of toxin-neutralizing antibody (TNA) titers that conferred protection against crude toxin challenge. These data suggest that genetically detoxified rSUMO-CPB m4 is a promising subunit vaccine candidate for C. perfringens type C beta enterotoxemia.

Objective: To understand the knowledge, attitude, and current status of vaccination of herpes zoster vaccination among urban residents aged 25 years and above in China. Methods: In August to October 2022, a convenience sampling method was used to survey residents aged 25 years and above at 36 community centers in 9 cities across China. Questionnaires were used to collect basic information, knowledge, and attitude toward herpes zoster and its vaccination, as well as vaccination status and reasons for non-vaccination among residents. Results: A total of 2 864 urban residents were included in the study. The total score of residents' cognition of herpes zoster and its vaccine was 3.01±2.08, and the total score of their attitude was 18.25±2.76. Factors such as being male ( β =-0.45, P <0.001), older than 40-59 years ( β =-0.34, P =0.023) or ≥60 years ( β =-0.68, P <0.001), married ( β =-0.69, P =0.002) were negatively associated with knowledge score. The educational level of high school or secondary school ( β =0.44, P =0.036), college ( β =0.65, P =0.006), bachelor's degree and above ( β =1.20, P <0.001), annual net household income ≥120 000 Yuan in 2021 ( β =0.42, P =0.020), having urban employee medical insurance ( β =0.62, P =0.030), having public or commercial medical insurance ( β =0.65, P =0.033), and having a history of chickenpox ( β =0.29, P =0.025) were positively associated with knowledge scores. Being male ( β =-0.38, P =0.008) and not remembering a history of chickenpox ( β =-0.49, P =0.012) were negatively associated with attitude scores. Annual net household income in 2021 was between 40 000-80 000 Yuan ( β =0.44, P =0.032) or between 80 000-120 000 Yuan ( β =0.62, P =0.002) or ≥120 000 Yuan ( β =0.93, P <0.001), and a history of herpes zoster ( β =0.59, P =0.004) were positively associated with attitude scores. Of the 2 864 residents surveyed, only 29 (1.01%) had received the herpes zoster vaccine, with a vaccination rate of 1.70% for those aged 50 years and above, with the main reason for non-vaccination being lack of knowledge about the herpes zoster vaccine, followed by the high price. 42.67% of the population said they would consider getting the herpes zoster vaccine in the future. Conclusion: Low knowledge of herpes zoster and its vaccine, positive attitudes towards the preventive effects of herpes zoster and its vaccine, and extremely low vaccination rates among the urban population in China call for multiple measures to strengthen health education and vaccination recommendations for residents, especially for the elderly, low-education and low-income populations.

To explore the genetic causes of 3 male infertility patients with acephalospermia and the outcome of assisted reproductive technology. Clinical diagnosis, sperm morphology examination, sperm transmission electron microscopy examination were performed on 3 patients, and the whole exome sequencing technology was used for screening, Sanger sequencing verification, mutation pathogenicity analysis, and protein sequence homology comparison. Assisted reproductive technology was implemented to assist pregnancy treatment. The 3 patients were all sporadic infertile men, aged 25, 42 and 26 years, and there was no obvious abnormality in the general physical examination. Male external genitalia developed normally, bilateral testicles were normal in volume, and bilateral epididymis and spermatic vein were palpated without nodules, cysts, and tenderness. Repeated semen analysis showed that a large number of immature sperm could be seen, and they had the ability to move. The SUN5 gene of the 3 male infertile patients was a case of homozygous missense mutation c.7C>T (p.Arg3Trp), a case of compound heterozygous missense mutation c.1067G>A (p.Arg356His) and nonsense mutation c.216G>A (p.Trp72*) and a case of homozygous missense mutation c.1043A>T (p.Asn348Ile), of which c.7C>T (p.Arg3Trp) and c.1067G>A (p.Arg356His) were new variants that had not been reported. SIFT, Mutation Taster and PolyPhen-2 software function prediction results were all harmful, the nonsense mutation c.216G>A (p.Trp72*) led to the premature termination of peptide chain synthesis which might have a greater impact on protein function. The homology regions in the protein sequence homology alignment were all highly conserved.The 3 male patients and their spouses obtained 4 biological offspring through intracytoplasmic sperm injection, all of which were boys, and one of them was a twin.Three male infertile patients might be caused by SUN5 gene mutations. Such patients could obtain their biological offspring through assisted reproductive technology. It was still necessary to pay attention to the genetic risk of ASS, it was recommended that both men and women conduct genetic counseling and screening at the same time. In clinical diagnosis, whole exome sequencing technology could be used to perform auxiliary examinations to determine the treatment plan and assisted reproductive methods as soon as possible to reduce the burden on the family and society. The newly discovered mutation sites of SUN5 gene provided clues and directions for elucidating the pathogenic mechanism, and at the same time expanded the pathogenic mutation spectrum of ASS.

Objective: To analysis the expression of CD7 in NK/T-cell lymphoma as well as study the correlations between CD7 and clinical survival and prognosis. Methods: The clinical and pathological indicators of 112 NKTCL patients who were admitted to or consulted at the First Affiliated Hospital of Zhengzhou University between May 2008 and December 2019 were analyzed retrospectively. The CD7 expression in the tumor tissues was detected using immunohistochemistry staining, and the influence of CD7 expression on the survival and prognosis in the patients was analyzed. Results: The CD7 expression rate was 84.82% in 112 NKTCL patients, and its expression was not influenced by sex, age, and the primary site. An analysis of the complete clinical data of 72 patients showed that the CD7 expression was significantly correlated with the PINK score, tumor metastasis, and peripheral blood EBV-DNA level. However, the Ann Arbor stage, bone marrow involvement, B symptoms, IPI/aaIPI score, Ki-67, EBER, TIA-1, Granzyme B, LDH, and β(2)-MG were not associated with the CD7 expression. The 1-year, 3-year, and 5-year overall survival (OS) rates of the 72 patients were 81.2%, 61.8%, and 58.8%, respectively, and the progression-free survival (PFS) rates were 53.5%, 29.4%, and 24.0%, respectively. The median overall survival (median-OS, mOS) was 81 mon, and the median progression-free survival (median-PFS, mPFS) was 14 mon. The 3-year OS rates in the CD7-positive group and the CD7-negative group were 58.1% and 83.9%, respectively, ( P >0.05) . The 3-year PFS rates were 21.7% and 51.9%, respectively ( P <0.05) . The univariate analysis showed that age, primary tumor site, Ann Arbor stage, IPI/aaIPI score, PINK score, LDH, β(2)-microglobulin, EBV-DNA, Ki-67, and CD7 influenced patient prognosis. The multivariate analysis showed that Ann Arbor stage and CD7 were independent prognostic factors for PFS, while PINK score and Ki-67 were independent prognostic factors for OS. Conclusions: The expression rate of CD7 in NKTCL was high and was closely related to poor patient prognosis. The patients with high levels of EBV-DNA, metastatic disease, or high PINK score were more likely to express CD7.

Objective: To study the epidemiology and antimicrobial resistance of Gram-negative bacterial bloodstream infections in children, and to guide the choice of antimicrobials and the control of nosocomial infection. Method: Clinical data, bacteriology and antimicrobial susceptibility test results were collected retrospectively in hospitalized children who were diagnosed with gram-negative bacterial bloodstream infections in Yuying Children's Hospital of Wenzhou Medical University from January, 2010 to December, 2015. Result: A total of 399 cases (253 male and 146 female) were identified. The age ranged from 16 hours to 16 years (median age 10.1 months). The majority of cases were collected from division of neonatology ( n =261, 65.4%), followed by 31 cases (7.8%) from pediatric intensive care unit and 29 cases (7.3%) from Gastroenterology Department; 275 cases (68.9%) had underlying diseases, mainly including preterm birth( n =172), neonatal respiratory distress syndrome( n =67) and newborn asphyxia( n =53). Eighty cases had received invasive procedures and 20 had surgical operation; 149 cases (37.3%) were community-acquired and 250 cases (62.7%) were hospital acquired. Fifty cases had complications, among those, 40 cases had septic shock, 32 cases had multiple organ dysfunction syndrome and 7 cases had disseminated intravascular coagulation; 288 cases were cured, 48 improved, 17 gave up treatment and discharged, and 46 died; totally 408 strains were isolated from 399 children, including Enterobacteriaceae (346, 84.8%), non-fermentative Gram-negative bacteria (49, 12.0%) and other gram-negative bacteria (13, 3.2%). The resistance rates of Escherichia coli ( n =175) and Klebsiella pneumoniae ( n =106) to carbapenems, β-lactams enzyme and its inhibitors, amikacin and cefoxitin were all lower than 10%. Totally 245 multi-drug resistant strains (60.1%) were isolated, including 225 strains of Enterobacteriaceae and 18 strains of non-fermentative Gram-negative bacteria ( P <0.01) . Nine strains of Carbapenem-resistant Enterobacteriaceae were isolated, which were all sensitive to amikacin and the sensitive rates to fluoroquinolone reached 88.9%. Five strains which were detected sensitive to tigecycline were all sensitive. The proportion of Klebsiella sp in Gram-negative bacteria between 2013-2015 and 2010-2012 were 32.9% and 21.2%, respectively. The resistance rates of Escherichia coli and Klebsiella pneumoniae to β-lactams and its enzyme inhibitors and carbapenems had no significant change. Conclusion: Gram-negative bacterial bloodstream infections occur more frequently in newborns. Most children had combined underlying diseases. Escherichia coli and Klebsiella pneumoniae are the most common pathogens. β-Lactams and its enzyme inhibitors and carbapenems are the empirical choice of antimicrobial therapy for severe Enterobacteriaceae bloodstream bacterial infections.