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Lead is a kind of heavy metal, which is widely used in industry. Because of the wide application of lead, lead has caused great environmental pollution, and has been widely concerned in the world. On ... the other hand, the half-life of lead in the body is relatively long, so it can exist in human and animal bodies for a long time, which will have some bad effects on the reproductive system of human and animal, and the consequences are very serious. In this case, the effect of lead acetate on the growth and development of mouse blastocyst was studied. In this study, the mice were divided into high-dose group, low-dose group and control group. The high-dose group and low-dose group were exposed to different doses of lead acetate in vitro. In the course of the study, we studied the body weight of the female mice and the probability of ovarian and uterine malformation, and studied the development of the general signs and reflex function of the offspring mice. This study found that the probability of ovarian and uterine malformation in high-dose group was 40.70%, that in low-dose group was 12.63%, and that in control group was 10.99%. It can be seen that high dose of lead acetate can increase the abnormal rate of ovary and uterus of female rats. In addition, the results of this study showed that the development of general signs and reflex function of offspring rats exposed to high-dose lead acetate in vitro was slower than that of the other two groups. Keywords: Lead Acetate, in Vitro Exposure, Blastocyst Growth and Development, Physical Signs Development more

棉花体细胞再生植株、转基因植株、茎尖培养植株等无菌苗直接定植成活率低，在一定程度上制约了生物技术和细胞工程在棉花遗传改良等方面的应用，嫁接能够改善这一状况。本研究的目的是建立对大规模保存棉花遗传分离群体、稀有种质资源和远缘杂交不育材料具有特殊意义的高效嫁接技术。尝试用“顶插”、“劈接”和“合接”等不同方式对棉苗进行嫁接，探索新的高效棉花嫁接方法。得到高效棉花嫁接合接法。采用此法时应提前培育健壮棉苗做砧木，砧木的苗龄≥接穗的苗龄；砧木和接穗苗龄相差1～2片真叶时嫁接效果较好，接穗至少保持1片叶子。砧木和接穗为不同品种与砧木和接穗为同一品种相比，后者的嫁接成活率较高，但嫁接不受基因型的限制，各种类型的棉花材料均可嫁接。 “接合法”是实用有效的棉苗嫁接法。利用此技术大规模嫁接棉花转基因植株、遗传分离群体、常规棉株等，嫁接成活率在90%～100%。 Direct transplants of cotton somatic regenerated plants, transgenic plants and other types of sterile plantlets are rather difficult and normally have lower survival ratios. To some extent, low survival ratios limit the application of biotechnology and cyto-engineering in cotton genetic improvement. Cotton grafts can solve this problem preferably and conserve rare germplasm materials, genetic segregated populations and incompatible interspecies hybridization. In the study, a new highCefficient graft technique in cotton was explored and designated as the cotton join graft technique (CJG). Performance favored rootstocks and had more 1-2 leave

Novel kind of core-shell corona complex micelles were prepared, which enhanced both the hydrolytic stability and the photostability of water-soluble zinc tetrakis(4-sulfonatophenyl) porphyrin ... (ZnTPPS) in acidic aqueous solutions. The core-shell gold nanoparticles (AuNPS) were synthesized by reducing HAuCl 4 and di-thioester terminated block copolymer, poly(Nisopropylacrylamide)-block-poly(4-vinylpyridine) (PNIPAM-b-P4VP). The complex micelles with gold core, P4VP/ZnTPPS shell and PNIPAM corona were formed by simple mixing of gold nanoparticles and ZnTPPS. The photochemical properties of the complex micelles were studied by UV-Visiblespectroscopy and fluorescence spectroscopy. The results showed trapping of ZnTPPS in the positively charged micellar shell that effectively prevented demetallation of the ZnTPPS that would occur in acidic aqueous solutions. Furthermore, with appropriate concentration of gold nanoparticles, ZnTPPS in the complex micelle had excellent photostability by suppression of generation of reactive oxygen species (ROS). The enhanced stability of ZnTPPS in acidic aqueous media could be extensively used for photocatalysis and in solar cells. more

Background Dual antiplatelet therapy is considered beneficial in acute ischemic stroke (AIS) patients with intracranial artery stenosis (ICAS), with more bleeding events. Ginkgolide is shown to ... reduce platelet activation after infarction, which might be of benefit in AIS. We aimed to explore the effect of Ginkgolide in AIS patients with ICAS. Methods This was a randomized, double‐blinded, placebo‐controlled trial conducted at 61 centers in China. Within 72 h after onset, consecutive patients diagnosed as AIS with ICAS were randomized to either Ginkgolide or placebo treatment. The primary outcome was the composite of mortality and recurrent stroke (ischemic or hemorrhagic) during first 4 weeks in an intention‐to‐treat analysis. Secondary functional outcome was assessed by modified Rankin Scale and improvement of stroke severity was assessed by National Institution of Health Stroke Scale at day 28. Safety outcome was measured by the rate of severe adverse event (SAE). Results There were 936 patients randomized to either Ginkgolide or placebo treatment. Their average age was 64.2 ± 10.4 years old and 36.0% of the patients were female. The composite index event occurred in six patients in placebo group, and none occurred in Ginkgolide group (risk ratio 1.01; 95% CI 1.00–1.02). There were more patients who achieved favorable outcome in Ginkgolide group, compared with that of the placebo group (OR 2.16, 95%CI 1.37–3.41). SAE occurred in five (1.1%) patients in the Ginkgolide group and three (0.6%) in the placebo group (OR0.60, 95CI% 0.14–2.53). Intracranial hemorrhage occurred in 1/473 (0.2%) in the placebo group. Conclusions Ginkgolide, working as PAF antagonist, may reduce recurrent stroke in AIS with ICAS patients within 72 hours after onset. It might be an optional treatment in moderate‐to‐severe AIS patients with ICAS. (http://www.chictr.org.cn Number as ChiCTR‐IPR‐17012310). Although dual antiplatelet therapy is considered benefit in acute ischemic stroke (AIS) patients with intracranial artery stenosis (ICAS), there are more bleeding events. Ginkgolide, works as PAF antagonist, may reduce recurrent and mortality in AIS with large artery stenosis within 72 hours atfer onset during 90 days follow‐up. It might play a role of neuroprotection in AIS patients with ICAS more

In this work, we present a ligand modification strategy that allows for the regulation of the valence and dispersion state of Cu clusters in the final obtained Cu@C/SiO2 catalyst. Specifically, the ... phthalic acid (PA) ligand promotes the uniform anchoring of zero-valence Cu nanoclusters on Cu@C/SiO2, resulting in excellent catalytic activity in the selective reduction of toxic 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) with a rate constant (k) of 19.06×10-3 s-1. This value was approximately 2.4- and 31.2-fold higher than that of the CuO/SiO2 and bare CuO catalysts, respectively. Additionally, no significant decline in activity was detected during six successful cycles. Through systematic analysis of structural and electronic properties of the catalyst, we confirmed that the coordination effect of the PA ligand and the carbothermic effect of its carbon derivatives effectively prevent particle aggregation and modulate the valence state of copper species in Cu@C/SiO2, resulting in superior catalytic performance. The ligand modification strategy enables the simultaneous regulation in dispersion state and valence of Cu nanoclusters in Cu@C/SiO2, which accelerate electron transfer between substrates and active Cu centers during reaction, thus achieving a tremendously enhanced catalytic activity and excellent durability in 4-nitrophenol reduction process. Display omitted •Cu@C/SiO2 nanocomposite was synthesized via a ligand modification strategy.•The uniform dispersion and zero-valence nature of Cu nanoparticle was obtained.•Cu@C/SiO2 exhibited outstanding catalytic activity for the reduction of toxic 4-NP.•The carbon matrix endows Cu@C/SiO2 with high reusability. more

Learning evaluation system can improve the quality of teaching by scrutinizing and monitoring students' learning status. It not only enable students to better understand their academic performance, ... but also help teachers make more informed teaching decisions. This article constructed a learning intelligent evaluation system through intelligent evaluation and data mining, and compared it with traditional learning evaluation systems. Moreover, the subsequent survey questionnaire on students' attitudes towards the two systems in this article also showed that students are more inclined towards intelligent evaluation systems. Therefore, this study found and believed that intelligent evaluation and data mining can build learning evaluation systems that are more beneficial for students' learning. more

Resting cells of Arthrobacter simplex with 1‐en‐dehydrogenation ability were prepared and treated by ethanol at subinhibitory concentrations (4%–15%, v/v), then added into the ethanol‐free system ... containing low concentration of cortisone acetate (1 g L−1) to produce prednisone acetate by C1,2 dehydrogenation reaction. Results showed that, within the range of ethanol concentration, the initial conversion rate was varied significantly with the concentration of ethanol and the maximum was obtained at 8% (v/v) ethanol, which was increased by 32.6% compared with the control. A series of cell features closely relevant to biotransformation efficiency were further analyzed. It indicated that ethanol acting on cell wall and membrane could be used as a mediator to enhance cell permeability, which facilitated the penetration of substrate across cell barrier within a short time, resulting in the elevated initial conversation rate. The observation of fatty acids composition suggested that the increased unsaturated fatty acids, especially cis‐isomers, in the presence of ethanol led to the disorganization of the native arrangement of lipids and thus increased cell permeability. Our findings demonstrated that another facilitation of ethanol was to promote substrate transport into cells by permeabilization, which would provide the guidance in the practical application of organic solvents in steroid biotransformation. more

In agricultural irrigation, soil moisture is a key parameter that affects crop growth and development. Therefore, obtaining soil moisture information to develop artificial intervention and regulation ... measures is an important guarantee for stable production and a prerequisite for achieving intelligent irrigation. Adopting the most advanced technology for precision irrigation is an inevitable trend in the development of modern agriculture. However, when accurately predicting the soil moisture in the monitored area, there is a dilemma: a small number of fixed detection points for soil moisture cannot effectively reflect the soil moisture information in the crop area, and the large number of sensor detection points makes investment costs high. This article proposes a Fuzzy-PID adaptive soil moisture monitoring system that combines fuzzy control and PID control. By collecting real-time soil moisture, based on the principle of fuzzy control, on the one hand, the soil moisture is adaptively adjusted according to the growth characteristics of plants to keep crops "not hungry but full", and on the other hand, timely and appropriate irrigation is carried out to avoid waste of water resources while meeting the irrigation needs of greenhouses. The experimental results show that the system has accurate and reliable measurement data, good real-time performance, strong anti-interference ability, and can accurately and high-precision measure soil moisture. more