Search

In the paper, in view of two monotonicity rules for the ratios of two functions and of two Maclaurin power series expansions, the authors establish several sharp inequalities involving (hyperbolic) tangent, tanc, cosine, and their reciprocals. [ABSTRACT FROM AUTHOR]

Ammonium‐calcium mixed‐cation pentaborate NH4Ca[B5O7(OH)4]·H2O has been synthesized for the first time. Single‐crystal X‐ray diffraction analysis reveals that it crystallizes in the triclinic space group P‐1 with lattice parameters a = 6.7042(3) Å, b = 7.1859(3) Å, c = 10.7447(4) Å, α = 100.304(3), β = 97.774(3), γ = 96.972(3). The structure is characterized by 1D boron–oxygen chains composed of [B5O7(OH)4]3− polyanions that are further interspaced by Ca2+, NH4+ cations, along with lattice water molecules. The phase purity and thermal stability of the as‐synthesized sample were confirmed by XPRD and TG‐DSC analyses. Experimental UV–vis diffuse reflectance spectroscopy coupled with Urbach fitting indicates a direct bandgap of 4.50 eV, contrasting with theoretical calculations that suggest an indirect bandgap of 5.53 eV. Additionally, both theoretical computation and polarized light experimental test indicate that NH4Ca[B5O7(OH)4]·H2O exhibits moderate birefringence. [ABSTRACT FROM AUTHOR]

The Central Asian Orogenic Belt (CAOB) was formed by the aggregation and collage of numerous Paleozoic subduction‐accretion assemblages and Precambrian microcontinental blocks. However, the tectonic nature of the southeastern CAOB remains controversial, which complicates the reconstruction of the Paleo‐Asian Ocean. To address this issue, a deep seismic reflection survey was initiated across the southeastern CAOB and reveals broad gentle sub‐horizontal reflectors in the middle‐lower crust and a relatively transparent zone in the upper crust. Combining with the Precambrian geological outcrops and other geophysical features, we support a microcontinental block, the Xilinhot Block, existed in the Paleo‐Asian domain. Thus, the Paleo‐Asian Ocean was separated into two branches that underwent north‐dipping and double‐dipping oceanic plate subduction, respectively, to form the Hegenshan‐Heihe and Solonker sutures. Multiple relics beneath Hegenshan‐Heihe Suture indicate that multiple sets of unidirectional oceanic subduction‐accretion and magmatism were important mechanisms of continental growth. Plain Language Summary: During the consumption of the Paleo‐Asian Ocean, a great number of Paleozoic subduction‐related accretionary complexes were developed and combined with pre‐existing Precambrian continental fragments to form the Central Asian Orogenic Belt (CAOB). However, research on the tectonic evolution of this area has been limited, and the tectonic nature of the southeastern CAOB remains controversial. A deep seismic reflection survey along the southeastern CAOB shows the crustal architecture in detail. The broad gentle sub‐horizontal reflectors and a relatively transparent zone in the profile reveal a Precambrian continental fragment existed in the North Orogenic Belt of CAOB. The Paleo‐Asian Ocean was further separated into two parts, the fossil subduction zones of which show northward and bidirectional dipping characteristics beneath the Hegenshan‐Heihe and Solonker sutures, respectively. Several relics of the unidirectional subduction beneath the Hegenshan‐Heihe Suture indicate that multiple sets of unidirectional oceanic subduction‐accretion and magmatism were important mechanisms of continental growth. Key Points: A preserved microcontinental block has been revealed in the North Orogenic Belt of Central Asian Orogenic BeltThe Paleo‐Asian Ocean was separated into two branches, which were closed respectively by north‐dipping and double‐dipping subductionMultiple unidirectional subduction‐accretion and oceanic magmatism may contribute to continental growth [ABSTRACT FROM AUTHOR]

Three species of the spider family Philodromidae are reported from the south of China. A new genus, Sinodromus gen. nov., is described from Jiangxi, Fujian, and Hunan Provinces. It can be distinguished from other genera of Philodromidae by the tegular apophysis of the palp and the cymbial process, as well as by its uniquely striped abdomen. The type species, S. fujianensis sp. nov., and a second species, S. perbrevis sp. nov., are described and illustrated; these species occur in bamboo forests in hilly areas. Additionally, the female of Philodromus guiyang Long & Yu, 2022 is described for the first time from Jiangxi and Hunan Provinces. All species are illustrated with SEM micrographs, and their distributions are mapped. [ABSTRACT FROM AUTHOR]

The purpose of the experiment was to screen beneficial strains with antibacterial effects from the natural environment and study their growth characteristics. In the experiment, 12 strains of Bacillus were screened with E. coli as indicator bacteria, and six strains of Bacillus with antibacterial activity were screened and identified. Then, Escherichia coli and Staphylococcus aureus were used as indicator bacteria to screen the antibacterial peptide extracts of Bacillus, and hemolytic comparison, drug sensitivity determination, and growth characteristics of the screened strains were studied. The results showed that Bacillus G02 and J12, which had strong antibacterial activity, were identified as Bacillus siamensis. The extracts of two strains of Bacillus had the ability of secreting surface activity, and the ability of secreting surface activity was equal. The sensitivity of two strains of Bacillus to 16 drugs was above medium sensitivity. The extracts of two strains of Bacillus had the ability of secreting surface activity, and the ability of secreting surface activity was equal. The sensitivity of two strains of Bacillus to 16 drugs was above medium sensitivity. The two strains entered the logarithmic growth phase at 6 h, the pH value was maintained between 5 and 8, and the antimicrobial activity reached its peak at 22 h. Studies have shown that Bacillus has the ability to produce a variety of active peptides, and has a certain inhibitory effect on common pathogenic bacteria, which is a potential substitute for traditional antibiotics. [ABSTRACT FROM AUTHOR]

Our objective was to investigate the status and influence of myopia among primary school students in Fushun, Liaoning Province, China. We aimed to provide a theoretical and epistemological basis for implementing myopia prevention initiatives. We employed cluster sampling and surveyed 5216 primary school students from grades 1–6 across eight primary schools in Fushun City. Our participants included 2606 males and 2610 females whose average age was 9.25 (SD = 1.76) years. The rate of myopia among these primary school students was 29.54%, with statistically significant differences among students of different genders and grades. Logistic regression analysis further identified several possible protective factors, including appropriate reading distance, adequate home lighting, regular breaks between classes, conscientious eye exercises, and daily outdoor physical activity. Conversely, the associated risk factors were being female, being in a higher grade level, spending more than 4 hours on homework, occasionally reading while lying down, and having one or both parents with myopia. Overall, our results indicated a high incidence of myopia, highlighting the need for scientifically controlled interventions to manage and mitigate the occurrence and progression of myopia in this population. [ABSTRACT FROM AUTHOR]