Normal families and shared values of meromorphic functions

AbstractLet k(⩾2) be a positive integer, let F be a family of meromorphic functions in a domain D, all of whose zeros have multiplicity at least k+1, and let a(z)(≠0), h(z)(≢0) be two holomorphic functions on D. If, for each f∈F, f=a(z)⇔f(k)=h(z), then F is normal in D

Ethnobotany of dye plants in Dong communities of China

BACKGROUND: Dyes derived from plants have an extensive history of use for coloring food and clothing in Dong communities and other indigenous areas in the uplands of China. In addition to use as coloring agents, Dong communities have historically utilized dye plants for their value for enhancing the nutritive, medicinal and preservative properties of foods. However, the persistence of plant-derived dyes and associated cultural practices and traditional knowledge is threatened with rapid socio-economic change in China. Research is needed to document the ethnobotany of dye plants in indigenous communities towards their conservation and potential commercialization as a sustainable means of supporting local development initiatives. METHODS: Semi-structured surveys on plants used for coloring agents and associated traditional knowledge were conducted in fifteen Dong villages of Tongdao County in Hunan Province of South Central China during 2011–2012. Transect walks were carried out with key informants identified from semi-structured surveys to collect samples and voucher specimens for each documented plant species for taxonomic identification. RESULTS: Dong households at the study sites utilize the flowers, bark, stems, tubers and roots of 13 plant species from 9 families as dyes to color their customary clothing and food. Out of the documented plants, a total of 7 are used for coloring food, 3 for coloring clothing and 3 for both food and clothing. Documented plants consist of 3 species that yield black pigments, 3 for brownish red/russet pigments, 3 for red pigments, 2 for dark blue pigments and 2 for yellow pigments. In addition to dyes, the plants have multiple uses including medicinal, ornamental, sacrificial, edible, and for timber. CONCLUSIONS: The use of dyes derived from plants persists at the study sites for their important role in expressing Dong cultural identity through customary clothing and food. Further research is needed to evaluate the safety of dye plants, their efficacy in enhancing food items and their commercial potential. Conservation policies and management plans are called for to preserve these ethnobotanical resources in a sustainable manner that supports local livelihoods while maintaining cultural practices

Study on dynamic strength and liquefaction mechanism of silt soil in Castor earthquake prone areas under different consolidation ratios

Under the Castor earthquake, there is a risk of liquefaction instability of saturated tailings, and the evolution of dynamic pore pressure can indirectly reflect its instability process. Before applying dynamic loads, the static stress state of soil is one of the main factors affecting the development of soil dynamic strength and dynamic pore pressure, and there are significant differences in soil dynamic strength under different consolidation ratios. This paper conducted dynamic triaxial tests on saturated tailings silt with different consolidation ratios, and analyzed the dynamic strength variation and liquefaction mechanism of the samples using the discrete element method (PFC3D). The results showed that 1) as the Kc′ gradually increased, and there was a critical consolidation ratio Kc′ during the development of the dynamic strength of the sample. The specific value of Kc′ was related to the properties and stress state of saturated sand. The Kc′ in this research was about 1.9. When Kc < 1.9, dynamic strength was increased with the increase in Kc; when Kc > 1.9, dynamic strength was decreased with the Kc. 2) Under the impact of cyclic load, when samples were normally consolidated (Kc =1), the pore water pressure would tend to be equal to the confining pressure to cause soil liquefaction. In the case of eccentric consolidation (Kc > 1), the pore water pressure would be less than the confining pressure, thus, the soil liquefaction would not be induced, and the pore pressure value would decrease with the increase of consolidation ratio. This paper provides engineering guidance value for the study of dynamic strength and liquefaction mechanism of tailings sand and silt in Castor earthquake prone areas under different consolidation ratios

Rif1 Maintains Telomere Length Homeostasis of ESCs by Mediating Heterochromatin Silencing

SummaryTelomere length homeostasis is essential for genomic stability and unlimited self-renewal of embryonic stem cells (ESCs). We show that telomere-associated protein Rif1 is required to maintain telomere length homeostasis by negatively regulating Zscan4 expression, a critical factor for telomere elongation by recombination. Depletion of Rif1 results in terminal hyperrecombination, telomere length heterogeneity, and chromosomal fusions. Reduction of Zscan4 by shRNA significantly rescues telomere recombination defects of Rif1-depleted ESCs and associated embryonic lethality. Further, Rif1 negatively modulates Zscan4 expression by maintaining H3K9me3 levels at subtelomeric regions. Mechanistically, Rif1 interacts and stabilizes H3K9 methylation complex. Thus, Rif1 regulates telomere length homeostasis of ESCs by mediating heterochromatic silencing

Molecular characterization of florfenicol and oxazolidinone resistance in Enterococcus isolates from animals in China

Florfenicol is widely used for the treatment of bacterial infections in domestic animals. The aim of this study was to analyze the molecular mechanisms of florfenicol and oxazolidinone resistance in Enterococcus isolates from anal feces of domestic animals. The minimum inhibitory concentration (MIC) levels were determined by the agar dilution method. Polymerase chain reaction (PCR) was performed to analyze the distribution of the resistance genes. Whole-genome sequencing and comparative plasmid analysis was conducted to analyze the resistance gene environment. A total of 351 non-duplicated enteric strains were obtained. Among these isolates, 22 Enterococcus isolates, including 19 Enterococcus. faecium and 3 Enterococcus. faecalis, were further studied. 31 florfenicol resistance genes (13 fexA, 3 fexB, 12 optrA, and 3 poxtA genes) were identified in 15 of the 19 E. faecium isolates, and no florfenicol or oxazolidinone resistance genes were identified in 3 E. faecalis isolates. Whole-genome sequencing of E. faecium P47, which had all four florfenicol and oxazolidinone resistance genes and high MIC levels for both florfenicol (256 mg/L) and linezolid (8 mg/L), revealed that it contained a chromosome and 3 plasmids (pP47-27, pP47-61, and pP47-180). The four florfenicol and oxazolidinone resistance genes were all related to the insertion sequences IS1216 and located on two smaller plasmids. The genes fexB and poxtA encoded in pP47-27, while fexA and optrA encoded in the conjugative plasmid pP47-61. Comparative analysis of homologous plasmids revealed that the sequences with high identities were plasmid sequences from various Enterococcus species except for the Tn6349 sequence from a Staphylococcus aureus chromosome (MH746818.1). The current study revealed that florfenicol and oxazolidinone resistance genes (fexA, fexB, poxtA, and optrA) were widely distributed in Enterococcus isolates from animal in China. The mobile genetic elements, including the insertion sequences and conjugative plasmid, played an important role in the horizontal transfer of florfenicol and oxazolidinone resistance

Ultrasound-driven BaTiO3 nanorobots patching immunologic barrier to cure chronic rheumatoid arthritis

The disruption and reconstruction of the TREM2+ tissue resident macrophage (TRM) barrier on the surface of synovial lining play a key role in the activation and "remission" of rheumatoid arthritis (RA), which engender the prediction of this immunologic barrier as a potential driver for the achievement of "cure" in RA. However, strategies to promote the reconstruction of this barrier have not been reported, and the effect of patching this barrier remains unidentified. On the other hand, appropriate piezoelectric stimulation can reprogram macrophages, which has never been exerted on this barrier TRM yet. Herein, we design piezoelectric tetragonal BaTiO3 (BTO) ultrasound-driven nanorobots (USNRs) by the solvothermal synthesis method, which demonstrates satisfactory electro-mechanical conversion effects, paving the way to generate controllable electrical stimulation under ultrasound to reprogram the barrier TRM by minimally invasive injection into joint cavity. It is demonstrated that the immunologic barrier could be patched by this USNR effectively, thereby eliminating the hyperplasia of vessels and nerves (HVN) and synovitis. Additionally, TREM2 deficiency serum-transfected arthritis (STA) mice models are applied and proved the indispensable role of TREM2 in RA curing mediated by USNR. In all, our work is an interesting and important exploration to expand the classical tetragonal BTO nanoparticles in the treatment of autoimmune diseases, providing a new idea and direction for the biomedical application of piezoelectric ceramics

Survey of Tyrosine Kinase Signaling Reveals ROS Kinase Fusions in Human Cholangiocarcinoma

Cholangiocarcinoma, also known as bile duct cancer, is the second most common primary hepatic carcinoma with a median survival of less than 2 years. The molecular mechanisms underlying the development of this disease are not clear. To survey activated tyrosine kinases signaling in cholangiocarcinoma, we employed immunoaffinity profiling coupled to mass spectrometry and identified DDR1, EPHA2, EGFR, and ROS tyrosine kinases, along with over 1,000 tyrosine phosphorylation sites from about 750 different proteins in primary cholangiocarcinoma patients. Furthermore, we confirmed the presence of ROS kinase fusions in 8.7% (2 out of 23) of cholangiocarcinoma patients. Expression of the ROS fusions in 3T3 cells confers transforming ability both in vitro and in vivo, and is responsive to its kinase inhibitor. Our data demonstrate that ROS kinase is a promising candidate for a therapeutic target and for a diagnostic molecular marker in cholangiocarcinoma. The identification of ROS tyrosine kinase fusions in cholangiocarcinoma, along with the presence of other ROS kinase fusions in lung cancer and glioblastoma, suggests that a more broadly based screen for activated ROS kinase in cancer is warranted

Effects of Reproductive Status, Social Rank, Sex and Group Size on Vigilance Patterns in Przewalski's Gazelle

Quantifying vigilance and exploring the underlying mechanisms has been the subject of numerous studies. Less attention has focused on the complex interplay between contributing factors such as reproductive status, social rank, sex and group size. Reproductive status and social rank are of particular interest due to their association with mating behavior. Mating activities in rutting season may interfere with typical patterns of vigilance and possibly interact with social rank. In addition, balancing the tradeoff between vigilance and life maintenance may represent a challenge for gregarious ungulate species rutting under harsh winter conditions. We studied vigilance patterns in the endangered Przewalski's gazelle (Procapra przewalskii) during both the rutting and non-rutting seasons to examine these issues.Field observations were carried out with focal sampling during rutting and non-rutting season in 2008-2009. Results indicated a complex interplay between reproductive status, social rank, sex and group size in determining vigilance in this species. Vigilance decreased with group size in female but not in male gazelles. Males scanned more frequently and thus spent more time vigilant than females. Compared to non-rutting season, gazelles increased time spent scanning at the expense of bedding in rutting season. During the rutting season, territorial males spent a large proportion of time on rutting activities and were less vigilant than non-territorial males. Although territorial males may share collective risk detection with harem females, we suggest that they are probably more vulnerable to predation because they seemed reluctant to leave rut stands under threats.Vigilance behavior in Przewalski's gazelle was significantly affected by reproductive status, social rank, sex, group size and their complex interactions. These findings shed light on the mechanisms underlying vigilance patterns and the tradeoff between vigilance and other crucial activities