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The spinal cord is a crucial component of the central nervous system that facilitates sensory processing and motor performance. Despite its importance, the spatiotemporal codes underlying human spinal cord development have remained elusive. In this study, we have introduced an image-based single-cell transcription factor (TF) expression decoding spatial transcriptome method (TF-seqFISH) to investigate the spatial expression and regulation of TFs during human spinal cord development. By combining spatial transcriptomic data from TF-seqFISH and single-cell RNA-sequencing data, we uncovered the spatial distribution of neural progenitor cells characterized by combinatorial TFs along the dorsoventral axis, as well as the molecular and spatial features governing neuronal generation, migration, and differentiation along the mediolateral axis. Notably, we observed a sandwich-like organization of excitatory and inhibitory interneurons transiently appearing in the dorsal horns of the developing human spinal cord. In addition, we integrated data from 10× Visium to identify early and late waves of neurogenesis in the dorsal horn, revealing the formation of laminas in the dorsal horns. Our study also illuminated the spatial differences and molecular cues underlying motor neuron (MN) diversification, and the enrichment of Amyotrophic Lateral Sclerosis (ALS) risk genes in MNs and microglia. Interestingly, we detected disease-associated microglia (DAM)-like microglia groups in the developing human spinal cord, which are predicted to be vulnerable to ALS and engaged in the TYROBP causal network and response to unfolded proteins. These findings provide spatiotemporal transcriptomic resources on the developing human spinal cord and potential strategies for spinal cord injury repair and ALS treatment.

A thermal optical fiber sensor based on laser-heated GaAs film has been proposed and demonstrated in this work. The principle of the sensor is based on the hot-wire effect, that is, the convective heat loss from the laser-heated GaAs film to the fluid. An 810-nm fiber laser is used to heat the GaAs film due to its excellent opto-thermal effect. Due to the intrinsic thermal optical property of GaAs that the transmission spectrum shifts with temperature, the temperature change introduced by the flow can be demodulated by the spectral shifts of the reflection spectrum. The sensing principle and performance have been studied by numerical simulation based on finite-element analysis and have been verified by experiment. The maximum flow velocity sensitivity can reach 0.453 nm/(cm/s) over a broad range from 0.85 to 59 cm/s. The resolution is 0.5 cm/s, based on the wavelength resolution of 1.1 nm. Moreover, the micrometer-scale fiber sensor has good robustness, and the heating medium is also biologically compatible. Given its capability, compactness, and biocompatibility, the proposed flow velocity fiber sensor has a high application potential in invasive blood flow measurement.

The surface of GCr15SiMn bearing steel was strengthened by supersonic fine particle bombardment (SFPB), and the effects of different impact times on the microstructure, mechanical properties and friction and wear properties of the material were studied. The results show that the surface roughness of GCr15SiMn steel samples increases and the grain is refined after SFPB. As the impact time prolongs, the grain size gradually decreases. When the bombardment time is 180 s, the surface grain size of the sample reaches 12.7 nm. The microhardness of the sample gradually increases and tends to stabilize with the increase of the impact time. The residual compressive stress layer is produced on the surface of the sample after SFPB and the residual compressive stress shows a trend of first increasing and then decreasing with rising the impact time. The friction coefficient and wear rate of GCr15SiMn bearing steel decreases after SFPB. The wear mechanism of the sample changes from mixture of adhesive wear and oxidation wear, accompanied by slight abrasive wear (before SFPB) to the abrasive wear, supplemented by adhesive wear (after SFPB). The wear resistance is improved by the of the grain refinement and the formation of a high residual compressive stress layer.

Co-controlling the emissions of air pollutants and CO2from automobiles is crucial for addressing the intertwined challenges of air pollution and climate change in China. Here, we analyze the synergetic characteristics of air pollutant and CO2emissions from China’s on-road transportation and identify the co-drivers influencing these trends. Using detailed emission inventories and employing index decomposition analysis, we found that despite notable progress in pollution control, minimizing on-road CO2emissions remains a formidable task. Over 2010–2020, the estimated sectoral emissions of VOCs, NOx, PM2.5, and CO declined by 49.9%, 25.9%, 75.2%, and 63.5%, respectively, while CO2emissions increased by 46.1%. Light-duty passenger vehicles and heavy-duty trucks have been identified as the primary contributors to carbon-pollution co-emissions, highlighting the need for tailored policies. The driver analysis indicates that socioeconomic changes are primary drivers of emission growth, while policy controls, particularly advances in emission efficiency, can facilitate co-reductions. Regional disparities emphasize the need for policy refinement, including reducing dependency on fuel vehicles in the passenger subsector and prioritizing co-reduction strategies in high-emission provinces in the freight subsector. Overall, our study confirms the effectiveness of China’s on-road control policies and provides valuable insights for future policy makers in China and other similarly positioned developing countries.

Ammonium acetate (NH4Ac) is a widely used solvent additive in native electrospray ionization (ESI) mass spectrometry. NH4Ac can undergo proton transfer to form ammonia and acetic acid (NH4++ Ac–→ NH3+ HAc). The volatility of these products ensures that electrosprayed ions are free of undesired adducts. NH4Ac dissolution in water yields pH 7, providing “physiological” conditions. However, NH4Ac is not a buffer at pH 7 because NH4+and Ac–are not a conjugate acid/base pair (Konermann, L. J. Am. Soc. Mass Spectrom.2017, 28, 1827–1835.). In native ESI, it is desirable that analytes experience physiological conditions not only in bulk solution but also while they reside in ESI droplets. Little is known about the internal milieu of NH4Ac-containing ESI droplets. The current work explored the acid/base chemistry of such droplets, starting from a pH 7 analyte solution. We used a two-pronged approach involving evaporation experiments on bulk solutions under ESI-mimicking conditions, as well as molecular dynamics simulations using a newly developed algorithm that allows for proton transfer. Our results reveal that during droplet formation at the tip of the Taylor cone, electrolytically generated protons get neutralized by Ac–, making NH4+the net charge carriers in the weakly acidic nascent droplets. During the subsequent evaporation, the droplets lose water as well as NH3and HAc that were generated by proton transfer. NH3departs more quickly because of its greater volatility, causing the accumulation of HAc. Together with residual Ac–, these HAc molecules form an acetate buffer that stabilizes the average droplet pH at 5.4 ± 0.1, as governed by the Henderson–Hasselbalch equation. The remarkable success of native ESI investigations in the literature implies that this pH drop by ∼1.6 units relative to the initially neutral analyte solution can be tolerated by most biomolecular analytes on the short time scale of the ESI process.

Iron is important for life, and iron deficiency impairs development, but whether the iron level regulates neural differentiation remains elusive. In this study, with iron-regulatory proteins (IRPs) knockout embryonic stem cells (ESCs) that showed severe iron deficiency, we found that the Pax6- and Sox2-positive neuronal precursor cells and Tuj1 fibers in IRP1−/−IRP2−/−ESCs were significantly decreased after inducing neural differentiation. Consistently, in vivostudy showed that the knockdown of IRP1in IRP2−/−fetal mice remarkably affected the differentiation of neuronal precursors and the migration of neurons. These findings suggest that low intracellular iron status significantly inhibits neurodifferentiation. When supplementing IRP1−/−IRP2−/−ESCs with iron, these ESCs could differentiate normally. Further investigations revealed that the underlying mechanism was associated with an increase in reactive oxygen species (ROS) production caused by the substantially low level of iron and the down-regulation of iron-sulfur cluster protein ISCU, which, in turn, affected the proliferation and differentiation of stem cells. Thus, the appropriate amount of iron is crucial for maintaining normal neural differentiation that is termed ferrodifferentiation.

Microglial activation following peripheral nerve injury is crucial for neuropathic pain (NP) development; however, studies on time-specific and spatial characteristics of microglial transcriptome are scarce. Firstly, we comparatively analysed microglial transcriptome of different brain regions and multiple timepoints after nerve injury by analysing the gene expression profile of GSE180627 and GSE117320. Then, we performed a mechanical pain hypersensitivity test on 12 rat neuropathic pain models using von Frey fibres at various timepoints after nerve injury. To further explore the key gene clusters closely related to the neuropathic pain phenotype, we conducted a weighted gene co-expression network analysis (WGCNA) on the GSE60670 gene expression profile. Lastly, we performed a single-cell sequencing analysis on GSE162807 for identifying microglia subpopulations. We found that the trend of microglia’s transcriptome changes after nerve injury was that mRNA expression changes mainly occur early after injury, which is also consistent with phenotypic changes (NP progression). We also revealed that in addition to spatial specificity, microglia are also temporally specific in NP progression following nerve injury. The WGCNA findings revealed that the functional analysis of the key module genes emphasized the endoplasmic reticulum’s (ER’s) crucial role in NP. In our single-cell sequencing analysis, microglia were clustered into 18 cell subsets, of which we identified specific subsets of two timepoints (D3/D7) post-injury. Our study further revealed the temporal and spatial gene expression specificity of microglia in neuropathic pain. These results contribute to our comprehensive understanding of the pathogenic mechanism of microglia in neuropathic pain.

Henagliflozin proline and metformin hydrochloride sustained‐release tablets (HR20033) are a fixed‐dose combination of the novel, highly selective, and effective sodium‐glucose cotransporter‐2 inhibitor henagliflozin, with a metformin sustained‐release layer for the treatment of type 2 diabetes mellitus in conjunction with dietary control and exercise. The aims of this study were to investigate the effect of a high‐fat diet on the pharmacokinetics of henagliflozin and metformin after a single administration of HR20033 and the effect of repeated oral administration of HR20033 on their pharmacokinetics in healthy volunteers. The food‐effect clinical study involved 18 healthy subjects randomized to receive either HR20033 in the fasted condition followed by HR20033 in the fed condition or the reverse schedule, with the two doses separated by a washout period of at least 7 days. The multiple‐dose clinical study was conducted on 10 healthy subjects. In the food‐effect study, compared with those in the fasted condition, the area under the blood concentration curve (AUC) and peak concentration (Cmax) of henagliflozin decreased by 12.64% and 40.89%, respectively, while the AUC of metformin increased by 31.13% and Cmaxdecreased by 7.09% in the fed state. There was no significant accumulation of HR20033 in the body after multiple oral doses. No serious adverse event was observed in either of the two clinical studies. Food did not have a clinically meaningful effect on the absorption of HR20033.

Lissencephaly is a rare brain malformation for which our understanding remains limited due to the absence of suitable animal models that accurately represent human phenotypes. Here, we establish doublecortin (DCX) knockout ferrets as a model that faithfully replicates key features of the disorder. We reveal the critical roles of DCX in neural progenitor cell proliferation and radial glial fiber extension, processes essential for normal cortical development. Utilizing single-nucleus RNA sequencing (snRNA-seq) and spatial transcriptomics, we provide a detailed atlas of the lissencephalic cortex, illustrating disrupted neuronal lamination and the specific interactions between inhibitory and excitatory neurons. These findings enhance our understanding of the cellular and molecular mechanisms underlying lissencephaly and highlight the potential of DCX knockout ferrets as a valuable tool for neurodevelopmental research, offering insights into both the pathology of lissencephaly and the general principles of brain development.

Poly(ADP-ribose) polymerase inhibitors (PARPis) exhibit remarkable anticancer activity in tumors with homologous recombination (HR) gene mutations. However, the role of other DNA repair proteins in PARPi-induced lethality remains elusive. Here, we reveal that FANCM promotes PARPi resistance independent of the core Fanconi anemia (FA) complex. FANCM-depleted cells retain HR proficiency, acting independently of BRCA1 in response to PARPis. FANCM depletion leads to increased DNA damage in the second S phase after PARPi exposure, driven by elevated single-strand DNA (ssDNA) gap formation behind replication forks in the first S phase. These gaps arise from both 53BP1- and primase and DNA directed polymerase (PRIMPOL)-dependent mechanisms. Notably, FANCM-depleted cells also exhibit reduced resection of collapsed forks, while 53BP1 deletion restores resection and mitigates PARPi sensitivity. Our results suggest that FANCM counteracts 53BP1 to repair PARPi-induced DNA damage. Furthermore, FANCM depletion leads to increased chromatin bridges and micronuclei formation after PARPi treatment, elucidating the mechanism underlying extensive cell death in FANCM-depleted cells.

ABSTRACTCircular RNAs (circRNAs) are regulatory endogenous RNAs in human diseases by sponging microRNAs (miRNAs) to affect the gene expression. However, little research focused on the circRNA/miRNA/mRNA axis in diabetic cataract. This study was performed for the exploration of circRNA phosphoprotein associated with glycosphingolipid-enriched microdomains 1 (circPAG1) in diabetic cataract. Human lens epithelial cells were treated with high glucose. The quantitative real-time polymerase chain reaction was used for the expression detection of circPAG1, microRNA-211-5p (miR-211-5p), and E2F transcription factor 3 (E2F3). Cell viability and proliferation were detected using Cell Counting Kit-8 assay and EdU assay. Cell apoptosis was analyzed by flow cytometry. The protein levels were measured by Western blot. Oxidative stress was assessed by malondialdehyde, reactive oxygen species, and superoxide dismutase via the corresponding detection kits. The target interaction was validated using the dual-luciferase reporter assay and RNA immunoprecipitation assay. The expression of circPAG1 was downregulated in diabetic cataract patients. The upregulation of circPAG1 could attenuate the high glucose-induced inhibition of cell viability and proliferation but promotion of cell apoptosis and oxidative stress. CircPAG1 served as a miR-211-5p sponge, and the protective role of circPAG1 was partly achieved by sponging miR-211-5p. MiR-211-5p targeted E2F3 and circPAG1 upregulated the E2F3 level by absorbing miR-211-5p. Inhibition of miR-211-5p repressed the high glucose-mediated cell dysfunction by increasing the expression of E2F3. This study clarified that circPAG1 protected human lens epithelial cells from the high glucose-induced cell damages by the mediation of miR-211-5p/E2F3 axis.

Radiation belt electron dropouts indicate electron flux decay to the background level during geomagnetic storms, which is commonly attributed to the effects of wave‐induced pitch angle scattering and magnetopause shadowing. To investigate the loss mechanisms of radiation belt electron dropouts triggered by a solar wind dynamic pressure pulse event on 12 September 2014, we comprehensively analyzed the particle and wave measurements from Van Allen Probes. The dropout event was divided into three periods: before the storm, the initial phase of the storm, and the main phase of the storm. The electron pitch angle distributions (PADs) and electron flux dropouts during the initial and main phases of this storm were investigated, and the evolution of the radial profile of electron phase space density (PSD) and the (μ, K) dependence of electron PSD dropouts (where μ, K, and L* are the three adiabatic invariants) were analyzed. The energy‐independent decay of electrons at L> 4.5 was accompanied by butterfly PADs, suggesting that the magnetopause shadowing process may be the major loss mechanism during the initial phase of the storm at L> 4.5. The features of electron dropouts and 90°‐peaked PADs were observed only for >1 MeV electrons at L< 4, indicating that the wave‐induced scattering effect may dominate the electron loss processes at the lower L‐shell during the main phase of the storm. Evaluations of the (μ, K) dependence of electron PSD drops and calculations of the minimum electron resonant energies of H+‐band electromagnetic ion cyclotron (EMIC) waves support the scenario that the observed PSD drop peaks around L* = 3.9 may be caused mainly by the scattering of EMIC waves, whereas the drop peaks around L* = 4.6 may result from a combination of EMIC wave scattering and outward radial diffusion.

The hippocampus is an important part of the limbic system in the human brain that has essential roles in spatial navigation and the consolidation of information from short-term memory to long-term memory1,2. Here we use single-cell RNA sequencing and assay for transposase-accessible chromatin using sequencing (ATAC–seq) analysis to illustrate the cell types, cell linage, molecular features and transcriptional regulation of the developing human hippocampus. Using the transcriptomes of 30,416 cells from the human hippocampus at gestational weeks 16–27, we identify 47 cell subtypes and their developmental trajectories. We also identify the migrating paths and cell lineages of PAX6+and HOPX+hippocampal progenitors, and regional markers of CA1, CA3 and dentate gyrus neurons. Multiomic data have uncovered transcriptional regulatory networks of the dentate gyrus marker PROX1. We also illustrate spatially specific gene expression in the developing human prefrontal cortex and hippocampus. The molecular features of the human hippocampus at gestational weeks 16–20 are similar to those of the mouse at postnatal days 0–5 and reveal gene expression differences between the two species. Transient expression of the primate-specific gene NBPF1leads to a marked increase in PROX1+cells in the mouse hippocampus. These data provides a blueprint for understanding human hippocampal development and a tool for investigating related diseases.

Ertugliflozin, a sodium‐glucose cotransporter 2 inhibitor for the treatment of type 2 diabetes mellitus, prevents renal glucose reabsorption resulting in urinary glucose excretion. This open‐label, parallel cohort, randomized study conducted in healthy Chinese adults residing in China assessed the pharmacokinetics, tolerability, and safety of 5 mg and 15 mg of ertugliflozin following single (fasted condition) and multiple‐dose (fed condition) administration. Sixteen subjects were randomized and completed the study. Ertugliflozin absorption was rapid, with maximum plasma concentrations observed 1 hour after dosing under fasted conditions and 2 to 4 hours after dosing under fed conditions. Following single‐ and multiple‐dose administration, ertugliflozin exhibited dose‐proportional exposures with an apparent mean terminal half‐life of approximately 9.5 to 11.9 hours. Steady state was reached after 4 once‐daily doses. The accumulation ratio based on the area under the plasma concentration–time curve after multiple‐dose administration was approximately 1.3 and 1.2 for ertugliflozin 5 mg and 15 mg, respectively. Ertugliflozin was generally well tolerated following administration of single and multiple oral doses of 5 mg and 15 mg in healthy Chinese subjects. Pharmacokinetic comparison with non‐Asian subjects indicated that there are no clinically meaningful racial differences and no dose modification of ertugliflozin is required based on race or body weight.

LiTa2PO8(LTPO) is a novel inorganic ceramic electrolyte with high ionic conductivity. However, the synthetic materials are not ideal in performance and unstable to lithium metals. The doping of appropriate amount of the large radius element Ce4+can promote the growth of LTPO, enhance the communication between grains, and improve compactness. Meanwhile, Ce4+doping replaces part of Ta5+positions, broadens the lithium ion transport channel, and increases the LTPO room temperature ionic conductivity. The reaction of lithium metal with the multivalent element Ce3+/4+reduces the reduction of Ta5+by lithium metal and improves the stability of LTPO. The relative density of the prepared Li1.04Ta1.96Ce0.04PO8sample reaches 94.13 % and the room temperature ionic conductivity is 7.26 × 10−4 S/cm nearly 4.5 times higher than that without doped (1.65 × 10−4 S/cm). Moreover, Li1.04Ta1.96Ce0.04PO8shows a stable cycling performance in the symmetric Li/Li cells and Li/LiFePO4Solid-state batteries.

The emergence of the three germ layers and the lineage-specific precursor cells orchestrating organogenesis represent fundamental milestones during early embryonic development. We analyzed the transcriptional profiles of over 400,000 cells from 14 human samples collected from post-conceptional weeks (PCW) 3 to 12 to delineate the dynamic molecular and cellular landscape of early gastrulation and nervous system development. We described the diversification of cell types, the spatial patterning of neural tube cells, and the signaling pathways likely involved in transforming epiblast cells into neuroepithelial cells and then into radial glia. We resolved 24 clusters of radial glial cells along the neural tube and outlined differentiation trajectories for the main classes of neurons. Lastly, we identified conserved and distinctive features across species by comparing early embryonic single-cell transcriptomic profiles between humans and mice. This comprehensive atlas sheds light on the molecular mechanisms underlying gastrulation and early human brain development.

Resolution of ultrafine anaphase bridges (UFBs) must be completed before cytokinesis to ensure sister-chromatid disjunction. RIF1 is involved in UFB resolution by a mechanism that is not yet clear. Here, we show that RIF1 functions in mitosis to inhibit the formation of 53BP1 nuclear bodies and micronuclei. Meanwhile, RIF1 localizes on PICH-coated double-stranded UFBs but not on RPA-coated single-stranded UFBs. Depletion of RIF1 leads to an elevated level of RPA-coated UFBs, in a BLM-dependent manner. RIF1 interacts with all three isoforms of protein phosphatase 1 (PP1) at its CI domain in anaphase when CDK1 activity declines. CDK1 negatively regulates RIF1-PP1 interaction via the CIII domain of RIF1. Importantly, depletion of PP1 phenocopies RIF1 depletion, and phosphorylation-resistant mutant of PICH shows reduced interaction with the BTR complex and bypasses the need of RIF1 in preventing the formation of single-stranded UFBs. Overall, our data show that PP1 is the effector of RIF1 in UFB resolution.

Overall survival (OS) is considered the standard clinical endpoint to support effectiveness claims in new drug applications globally, particularly for lethal conditions such as cancer. However, the source and reliability of OS in the setting of clinical trials have seldom been doubted and discussed. This study first raised the common issue that data integrity and reliability are doubtful when we collect OS information or other time-to-event endpoints based solely on simple follow-up records by investigators without supporting material, especially since the 2019 COVID-19 pandemic. Then, two rounds of discussions with 30 Chinese experts were held and 12 potential source scenarios of three methods for obtaining the time of death of participants, including death certificate, death record and follow-up record, were sorted out and analysed. With a comprehensive assessment of the 12 scenarios by legitimacy, data reliability, data acquisition efficiency, difficulty of data acquisition, and coverage of participants, both short-term and long-term recommended sources, overall strategies and detailed measures for improving the integrity and reliability of death date are presented. In the short term, we suggest integrated sources such as public security systems made available to drug inspection centres appropriately as soon as possible to strengthen supervision. Death certificates provided by participants’ family members and detailed standard follow-up records are recommended to investigators as the two channels of mutual compensation, and the acquisition of supporting materials is encouraged as long as it is not prohibited legally. Moreover, we expect that the sharing of electronic medical records and the legal disclosure of death records in established health registries can be realized with the joint efforts of the whole industry in the long-term. The above proposed solutions are mainly based on the context of China and can also provide reference for other countries in the world.

ABSTRACTIsorhapontigenin (ISO) is a new derivative of stilbene isolated from the Chinese herb Gnetum cleistostachyum. Our recent studies have revealed that ISO treatment at doses ranging from 20 to 80 μM triggers apoptosis in multiple human cancer cell lines. In the present study, we evaluated the potential effect of ISO on autophagy induction. We found that ISO treatment at sublethal doses induced autophagy effectively in human bladder cancer cells, which contributed to the inhibition of anchorage-independent growth of cancer cells. In addition, our studies revealed that ISO-mediated autophagy induction occurred in a SESN2 (sestrin 2)-dependent and BECN1 (Beclin 1, autophagy related)-independent manner. Furthermore, we identified that ISO treatment induced SESN2 expression via a MAPK8/JNK1 (mitogen-activated protein kinase 8)/JUN-dependent mechanism, in which ISO triggered MAPK8-dependent JUN activation and facilitated the binding of JUN to a consensus AP-1 binding site in the SESN2promoter region, thereby led to a significant transcriptional induction of SESN2. Importantly, we found that SESN2 expression was dramatically downregulated or even lost in human bladder cancer tissues as compared to their paired adjacent normal tissues. Collectively, our results demonstrate that ISO treatment induces autophagy and inhibits bladder cancer growth through MAPK8-JUN-dependent transcriptional induction of SESN2, which provides a novel mechanistic insight into understanding the inhibitory effect of ISO on bladder cancers and suggests that ISO might act as a promising preventive and/or therapeutic drug against human bladder cancer.

Network virtualization is an enabling technology of running multiple virtual networks on a shared substrate network. It aims to deal with the ossification of current network architecture. As a crucial component of network virtualization, virtual network embedding (VNE) can efficiently and effectively allocates the substrate resource to proposed virtual network requests. According to the optimization strategy, VNE approaches can be classified into three categories: exact, heuristic and meta-heuristic solution. The VNE exact solution is the foundation of its corresponding heuristic and meta-heuristic solutions. This paper presents a survey of existing typical VNE exact solutions, and open problems for the future research of VNE exact solutions are proposed.

The complexity of the interlock firms' network is a miniature of the whole social economy system. This paper explored the regional interlock firms' network in China (including Guangdong, Zhejiang, Jiangsu, Shanghai and Beijing) through vertical and horizontal comparative analysis. The results demonstrated the ties and differences of the network in the historical, regional, structural and multiplicity scale. The conclusion is that both the amount and proportion of interlock firms are increased. By the influence of the degree of marketisation, industry characteristics and geographical position, the interlock directors in Beijing are more national and diversified, and those who are in Guangdong are local and lower diversified. The firms in Beijing and Shanghai tend to interlock cross-industry more. The firms in Zhejiang are significant in multiplicity. Those interlock firms network in Beijing and in Guangdong are relatively dispersive, compared to the firms in Shanghai, Jiangsu and Zhejiang which are more concentrated.

To assess the influence of individual methylenetetrahydrofolate reductase (MTHFR) C677T and methionine synthase A2756G polymorphisms on the change of serum folate concentration in response to different dosages and durations of folic acid (FA) supplementation in hypertensive Chinese adults.

AbstractThe paper analyzes the applicability of Weibull Density Distribution and Kernel Density Estimation in research of scientific productivity and collaboration group size. The datasets from five categories were retrieved and downloaded from ISI, and they are used to verify Kernel Density Estimation curve fits well with the Weibull Density Distribution curve. As a comparatively convenient function, Kernel Density Estimation can be used as a model to study the relationship between scientific productivity and group size. The best group size and reasonable group size are suggested through Kernel Density Estimation model. We assumed that the best group size in scientific cooperation is positive to discipline biology connotation, however, the result didn’t show such correlation obviously.

Compared with Lotka’s law, H. Kretschmer has referred to that the distribution of co-author pairs’ frequencies could be ideally reflected by a social gestalt. Among the former studies, small data sets from one journal and large data from several journals were investigated to verify these assumptions. In the present study, we will examine the data sets from a certain scientific subject “Energy Science and Technology” and its subfield “Solar Energy”, in order to testify that different configurations of social gestalt could reflect the characteristics of the cooperation in social networks, and meanwhile the data size as one of the factor will be proved, which could cause the convex or concave configurations of social gestalt.

In the present study, we try to identify the structure of scientific collaboration networks in scientometrics by using bibliographic data of all papers published by Chinese scientometricians in the international journal Scientometrics retrieved from the Science Citation Index (SCI) of the years 1978–2007. The study is based on bibliographic data retrieved from the Web of Science. The data contains all types of documents published by Chinese scientometricians in Scientometrics during 1978 to 2007.Combined analysis of social network analysis (SNA) and cooccurrence analysis is explored to reveal: (1) The structure of the international collaboration network of Chinese scientometrics; (2) The major collaborative fields of the whole network and of different collaborative sub-networks; (3) The collaborative center of the collaboration network in Chinese scientometrics; (4) The difference of the structure of international collaborative networks between China and India.