Single-cell characterization of self-renewing primary trophoblast organoids as modeling of EVT differentiation and interactions with decidual natural killer cells.

BACKGROUND: Extravillous trophoblast cell (EVT) differentiation and its communication with maternal decidua especially the leading immune cell type natural killer (NK) cell are critical events for placentation. However, appropriate in vitro modelling system and regulatory programs of these two events are still lacking. Recent trophoblast organoid (TO) has advanced the molecular and mechanistic research in placentation. Here, we firstly generated the self-renewing TO from human placental villous and differentiated it into EVTs (EVT-TO) for investigating the differentiation events. We then co-cultured EVT-TO with freshly isolated decidual NKs for further study of cell communication. TO modelling of EVT differentiation as well as EVT interaction with dNK might cast new aspect for placentation research. RESULTS: Single-cell RNA sequencing (scRNA-seq) was applied for comprehensive characterization and molecular exploration of TOs modelling of EVT differentiation and interaction with dNKs. Multiple distinct trophoblast states and dNK subpopulations were identified, representing CTB, STB, EVT, dNK1/2/3 and dNKp. Lineage trajectory and Seurat mapping analysis identified the close resemblance of TO and EVT-TO with the human placenta characteristic. Transcription factors regulatory network analysis revealed the cell-type specific essential TFs for controlling EVT differentiation. CellphoneDB analysis predicted the ligand-receptor complexes in dNK-EVT-TO co-cultures, which relate to cytokines, immunomodulation and angiogenesis. EVT was known to affect the immune properties of dNK. Our study found out that on the other way around, dNKs could exert effects on EVT causing expression changes which are functionally important. CONCLUSION: Our study documented a single-cell atlas for TO and its applications on EVT differentiation and communications with dNKs, and thus provide methodology and novel research cues for future study of human placentation.

Single-walled carbon nanotubes synthesized by laser ablation from coal for field-effect transistors.

Single-walled carbon nanotubes (SWCNTs) have been attracting extensive attention due to their excellent properties. We have developed a strategy of using coal to synthesize SWCNTs for high performance field-effect transistors (FETs). The high-quality SWCNTs were synthesized by laser ablation using only coal as the carbon source and Co-Ni as the catalyst. We show that coal is a carbon source superior to graphite with higher yield and better selectivity toward SWCNTs with smaller diameters. Without any pre-purification, the as-prepared SWCNTs were directly sorted based on their conductivity and diameter using either aqueous two-phase extraction or organic phase extraction with PCz (poly[9-(1-octylonoyl)-9H-carbazole-2,7-diyl]). The semiconducting SWCNTs sorted by one-step PCz extraction were used to fabricate thin film FETs. The transformation of coal into FETs (and further integrated circuits) demonstrates an efficient way of utilizing natural resources and a marvelous example in green carbon technology. Considering its short steps and high feasibility, it presents great potential in future practical applications not limited to electronics.

Corrigendum: Role and mechanism of DNA methylation and its inhibitors in hepatic fibrosis.

[This corrects the article DOI: 10.3389/fgene.2023.1124330.].

Role and mechanism of DNA methylation and its inhibitors in hepatic fibrosis.

Liver fibrosis is a repair response to injury caused by various chronic stimuli that continually act on the liver. Among them, the activation of hepatic stellate cells (HSCs) and their transformation into a myofibroblast phenotype is a key event leading to liver fibrosis, however the mechanism has not yet been elucidated. The molecular basis of HSC activation involves changes in the regulation of gene expression without changes in the genome sequence, namely, via epigenetic regulation. DNA methylation is a key focus of epigenetic research, as it affects the expression of fibrosis-related, metabolism-related, and tumor suppressor genes. Increasing studies have shown that DNA methylation is closely related to several physiological and pathological processes including HSC activation and liver fibrosis. This review aimed to discuss the mechanism of DNA methylation in the pathogenesis of liver fibrosis, explore DNA methylation inhibitors as potential therapies for liver fibrosis, and provide new insights on the prevention and clinical treatment of liver fibrosis.

Functionalized Lipid Nanocarriers for Simultaneous Delivery of Docetaxel and Tariquidar to Chemoresistant Cancer Cells.

The simultaneous drug delivery efficiency of a co-loaded single-carrier system of docetaxel (DTX)- and tariquidar (TRQ)-loaded nanostructured lipid carrier (NLC) functionalized with PEG and RIPL peptide (PRN) (D^T-PRN) was compared with that of a physically mixed dual-carrier system of DTX-loaded PRN (D-PRN) and TRQ-loaded PRN (T-PRN) to overcome DTX mono-administration-induced multidrug resistance. NLC samples were prepared using the solvent emulsification evaporation technique and showed homogeneous spherical morphology, with nano-sized dispersion (<220 nm) and zeta potential values of -15 to -7 mV. DTX and/or TRQ was successfully encapsulated in NLC samples (>95% encapsulation efficiency and 73-78 µg/mg drug loading). In vitro cytotoxicity was concentration-dependent; D^T-PRN exhibited the highest MDR reversal efficiency, with the lowest combination index value, and increased the cytotoxicity and apoptosis in MCF7/ADR cells by inducing cell-cycle arrest in the G2/M phase. A competitive cellular uptake assay using fluorescent probes showed that, compared to the dual nanocarrier system, the single nanocarrier system exhibited better intracellular delivery efficiency of multiple probes to target cells. In the MCF7/ADR-xenografted mouse models, simultaneous DTX and TRQ delivery using D^T-PRN significantly suppressed tumor growth as compared to other treatments. A single co-loaded system for PRN-based co-delivery of DTX/TRQ (1:1, w/w) constitutes a promising therapeutic strategy for drug-resistant breast cancer cells.

Novel albumin-binding photodynamic agent EB-Ppa for targeted fluorescent imaging guided tumour photodynamic therapy.

The targeted and novel albumin-binding strategy has been attractive in the field of cancer therapy. Herein, we have developed an organic small molecule-based photosensitizer, Evans Blue-Pyropheophorbide-alpha (EB-Ppa), to treat solid tumors with extremely high photodynamic therapeutic efficiency, which is stable in serum-containing aqueous media and can effectively accumulate in the tumor site due to the enhanced permeability and retention (EPR) effect. Particularly, after the photodynamic therapeutic treatment with EB-Ppa, all breast tumors (4T1 cell line) xenografted in nude mice shrink fast due to the singlet oxygen generated by EB-Ppa with laser irradiation. Furthermore, EB-Ppa shows negligible toxicity in major organs. These results demonstrate that EB-Ppa presents the great potential of photodynamic therapy for efficient tumor treatment.

Controlled Preparation of Single-Walled Carbon Nanotubes as Materials for Electronics.

Single-walled carbon nanotubes (SWCNTs) are of particular interest as channel materials for field-effect transistors due to their unique structure and excellent properties. The controlled preparation of SWCNTs that meet the requirement of semiconducting and chiral purity, high density, and good alignment for high-performance electronics has become a key challenge in this field. In this Outlook, we outline the efforts in the preparation of SWCNTs for electronics from three main aspects, structure-controlled growth, selective sorting, and solution assembly, and discuss the remaining challenges and opportunities. We expect that this Outlook can provide some ideas for addressing the existing challenges and inspire the development of SWCNT-based high-performance electronics.

Polyoxometalate steric hindrance driven chirality-selective separation of subnanometer carbon nanotubes.

Subnanometer single-chirality single-walled carbon nanotubes (SWCNTs) are of particular interest in multiple applications. Inspired by the interdisciplinary combination of redox active polyoxometalates and SWCNTs, here we report a cluster steric hindrance strategy by assembling polyoxometalates on the outer surface of subnanometer SWCNTs via electron transfer and demonstrate the selective separation of monochiral (6,5) SWCNTs with a diameter of 0.75 nm by a commercially available conjugated polymer. The combined use of DFT calculations, TEM, and XPS unveils the mechanism that selective separation is associated with tube diameter-dependent interactions between the tube and clusters. Sonication drives the preferential detachment of polyoxometalate clusters from small-diameter (6,5) SWCNTs, attributable to weak tube-cluster interactions, which enables the polymer wrapping and separation of the released SWCNTs, while strong binding clusters with large-diameter SWCNTs provide steric hindrance and block the polymer wrapping. The polyoxometalate-assisted modulation, which can be rationally customized, provides a universal and robust pathway for the separation of SWCNTs.

Study on Collision Detection Techniques for the Informed Design of Natural Views in Healthcare Environments.

BACKGROUND: Natural views are an important design strategy for the application of ecological resources in built environments. Numerous clinical studies have indicated that views of nature-for example, plants-can effectively promote patient recovery by relieving their postoperative pains and negative emotions during hospitalization. AIMS: This study demonstrates an intelligent method that develops algorithms of using collision detection techniques in Building Information Modeling to evaluate outdoor plant visibility for patients. METHODS: These algorithms are digitized into a Revit plug-in program, which can be viewed as a design-aided tool for architects with the purpose of informing healthcare environment design in the decision-making process. RESULTS: Its acceptability and effectiveness are evaluated based on the consultations in beta tests. CONCLUSIONS: It is believed that this method can improve the work efficiency of evaluating natural views in wards and help architects implement an informed design of built environments for better health performance. All findings in this study can contribute to the development of computational intelligence and social sustainability in the near future.

[Expression of LncRNA-MALAT1 in Peripheral Blood of Patients with Acute Myeloid Leukemia Sepsis and Its Clinical Significance].

OBJECTIVE: To analyze the expression of lncRNA-MALAT1 in peripheral blood of patients with acute myeloid leukemia (AML) sepsis and explore its clinical significance. METHODS: From March 2018 to March 2019, 95 confirmed AML patients including 43 sepsis infected cases and 52 uninfected cases were selected for treatment in the Department of Oncology and Hematology, The First People's Hospital of Longquanyi District. Their peripheral blood samples were taken as study samples, and the blood samples from 50 healthy people were used as control. RT-qPCR was used to detect lncRNA-MALAT1 expression level in samples from healthy group, uninfected group, and sepsis group. The correlation between lncRNA-MALAT1 expression level and clinical characteristics and prognosis of AML patients with sepsis were analyzed. RESULTS: The expression level of lncRNA-MALAT1 in the sepsis group was significantly up-regulated compared with the healthy group and uninfected group (P<0.05), while there was no significant difference between the healthy group and uninfected group (P>0.05). In AML patients with sepsis, the expression of lncRNA-MALAT1 was associated with clinical characteristics such as NCCN risk classification, white blood cell count, hemoglobin and so on. The overall survival rate of high lncRNA-MALAT1 expression group was significantly lower than that of low expression group (χ2=23.157, P=0.002). COX regression analysis showed that lncRNA-MALAT1 could be an independent prognostic factor for AML sepsis patients. CONCLUSION: The up-regulated expression of lncRNA-MALAT1 is closely related to the clinical characteristics and survival rate, and is an independent prognostic factor for AML sepsis patients. LncRNA-MALAT1 is expected to become a new diagnostic marker and therapeutic target for AML sepsis.

Development and validation of a nomogram for predicting survival of breast cancer patients with ipsilateral supraclavicular lymph node metastasis.

BACKGROUND: Breast cancer patients with ipsilateral supraclavicular lymph node metastasis (ISLNM) but without distant metastasis are considered to have a poor prognosis. This study aimed to develop a nomogram to predict the overall survival (OS) of breast cancer patients with ISLNM but without distant metastasis. METHODS: Medical records of breast cancer patients who received surgical treatment at the Affiliated Cancer Hospital of Zhengzhou University, Jiyuan People's Hospital and Huaxian People's Hospital between December 21, 2012 and June 30, 2020 were reviewed retrospectively. Overall, 345 patients with pathologically confirmed ISLNM and without evidence of distant metastasis were identified. They were further randomized 2:1 and divided into training (n = 231) and validation (n = 114) cohorts. A nomogram to predict the probability of OS was constructed based on clinicopathologic variables identified by the univariable and multivariable analyses. The predictive accuracy and discriminative ability were measured by calibration plots, concordance index (C-index), and risk group stratification. RESULTS: Univariable analysis showed that estrogen receptor-positive (ER+), progesterone receptor-positive (PR+), human epidermal growth factor receptor 2-positive (HER2+) with Herceptin treatment, and a low axillary lymph node ratio (ALNR) were prognostic factors for better OS. PR+, HER2+ with Herceptin treatment, and a low ALNR remained independent prognostic factors for better OS on multivariable analysis. These variables were incorporated into a nomogram to predict the 1-, 3-, and 5-year OS of breast cancer patients with ISLNM. The C-indexes of the nomogram were 0.737 (95% confidence interval [CI]: 0.660-0.813) and 0.759 (95% CI: 0.636-0.881) for the training and the validation cohorts, respectively. The calibration plots presented excellent agreement between the nomogram prediction and actual observation for 3 and 5 years, but not 1 year, OS in both the cohorts. The nomogram was also able to stratify patients into different risk groups. CONCLUSIONS: In this study, we established and validated a novel nomogram for predicting survival of patients with ISLNM. This nomogram may, to some extent, allow clinicians to more accurately estimate prognosis and to make personalized therapeutic decisions for individual patients with ISLNM.

Spatial variations in CO2 fluxes in a subtropical coastal reservoir of Southeast China were related to urbanization and land-use types.

Carbon dioxide (CO2) emissions from aquatic ecosystems are important components of the global carbon cycle, yet the CO2 emissions from coastal reservoirs, especially in developing countries where urbanization and rapid land use change occur, are still poorly understood. In this study, the spatiotemporal variations in CO2 concentrations and fluxes were investigated in Wenwusha Reservoir located in the southeast coast of China. Overall, the mean CO2 concentration and flux across the whole reservoir were 41.85 ± 2.03 µmol/L and 2.87 ± 0.29 mmol/m2/h, respectively, and the reservoir was a consistent net CO2 source over the entire year. The land use types and urbanization levels in the reservoir catchment significantly affected the input of exogenous carbon to water. The mean CO2 flux was much higher from waters adjacent to the urban land (5.05 ± 0.87 mmol/m2/hr) than other land use types. Sites with larger input of exogenous substance via sewage discharge and upstream runoff were often the hotspots of CO2 emission in the reservoir. Our results suggested that urbanization process, agricultural activities, and large input of exogenous carbon could result in large spatial heterogeneity of CO2 emissions and alter the CO2 biogeochemical cycling in coastal reservoirs. Further studies should characterize the diurnal variations, microbial mechanisms, and impact of meteorological conditions on reservoir CO2 emissions to expand our understanding of the carbon cycle in aquatic ecosystems.

Host-Guest Molecular Interaction Enabled Separation of Large-Diameter Semiconducting Single-Walled Carbon Nanotubes.

Semiconducting single-walled carbon nanotubes (s-SWCNTs) with a diameter of around 1.0-1.5 nm, which present bandgaps comparable to silicon, are highly desired for electronic applications. Therefore, the preparation of s-SWCNTs of such diameters has been attracting great attention. The inner surface of SWCNTs has a suitable curvature and large contacting area, which is attractive in host-guest chemistry triggered by electron transfer. Here we reported a strategy of host-guest molecular interaction between SWCNTs and inner clusters with designed size, thus selectively separating s-SWCNTs of expected diameters. When polyoxometalate clusters of ∼1 nm in size were filled in the inner cavities of SWCNTs, s-SWCNTs with diameters concentrated at ∼1.3-1.4 nm were selectively extracted with the purity of ∼98% by a commercially available polyfluorene derivative. The field-effect transistors built from the sorted s-SWCNTs showed a typical behavior of semiconductors. The sorting mechanisms associated with size-dependent electron transfer from nanotubes to inner polyoxometalate were revealed by the spectroscopic and in situ electron microscopic evidence as well as the theoretical calculation. The polyoxometalates with designable size and redox property enable the flexible regulation of interaction between the nanotubes and the clusters, thus tuning the diameter of sorted s-SWCNTs. The present sorting strategy is simple and should be generally feasible in other SWCNT sorting techniques, bringing both great easiness in dispersant design and improved selectivity.

Prediction of photosynthetic light-response curves using traits of the leaf economics spectrum for 75 woody species: effects of leaf habit and sun-shade dichotomy.

PREMISE: Photosynthetic light-response (PLR) curves for leaves are important components of models related to carbon fixation in forest ecosystems, linking the Mitscherlich equation and Michaelis-Menten equation to traits of the leaf economics spectrum (LES). However, models do not consider changes in leaf habits (i.e., evergreen and deciduous) and within-canopy shading variation in these PLR curves. METHODS: Here, we measured the PLR curves in sun and shade leaves of 44 evergreen and 31 deciduous species to examine the relationships between variables of the Mitscherlich equation and Michaelis-Menten equation, leaf nitrogen (N) and phosphorus (P) content, and leaf mass per area (LMA). RESULTS: Small changes were caused by different leaf habits and shade variations in relationships linking variables of the two equations to leaf N and P content and LMA. Values of the scaling exponents for PLR curve parameters did not differ regardless of canopy position and leaf habit (P > 0.05). The PLR curves in species with different leaf habits (i.e., evergreen and deciduous) at different canopy positions could be predicted using the general allometric relations between leaf traits and PLR parameters in the two equations. For photosynthetic photon flux densities from 0 to 2000 µmol m-2 s-1 , approximately 71% (Mitscherlich equation) and 70% (Michaelis-Menten equation) of the net assimilation rates could be predicted. CONCLUSIONS: These findings indicate that leaf net assimilation rates can be predicted through the large available data for LES traits. Incorporation of values for these traits available in the LES databases into ecosystem models of forest productivity and carbon fixation warrants further investigation.

Thermal Acclimation of Foliar Carbon Metabolism in Pinus taiwanensis Along an Elevational Gradient.

Climate change could negatively alter plant ecosystems if rising temperatures exceed optimal conditions for obtaining carbon. The acclimation of plants to higher temperatures could mitigate this effect, but the potential of subtropical forests to acclimate still requires elucidation. We used space-for-time substitution to determine the photosynthetic and respiratory-temperature response curves, optimal temperature of photosynthesis (T opt), photosynthetic rate at T opt, temperature sensitivity (Q 10), and the rate of respiration at a standard temperature of 25°C (R 25) for Pinus taiwanensis at five elevations (1200, 1400, 1600, 1800, and 2000 m) in two seasons (summer and winter) in the Wuyi Mountains in China. The response of photosynthesis in P. taiwanensis leaves to temperature at the five elevations followed parabolic curves, and the response of respiration to temperature increased with temperature. T opt was higher in summer than winter at each elevation and decreased significantly with increasing elevation. Q 10 decreased significantly with increasing elevation in summer but not winter. These results showed a strong thermal acclimation of foliar photosynthesis and respiration to current temperatures across elevations and seasons, and that R 25 increased significantly with elevation and were higher in winter than summer at each elevation indicating that the global warming can decrease R 25. These results strongly suggest that this thermal acclimation will likely occur in the coming decades under climate change, so the increase in respiration rates of P. taiwanensis in response to climatic warming may be smaller than predicted and thus may not increase atmospheric CO2 concentrations.

[Analysis of clinical characteristics of a pedigree with familial renal cell carcinoma and germline mutation of VHL gene].

OBJECTIVE: To detect germline mutation in a pedigree affected with familial renal cell carcinoma and explore its molecular pathogenesis. METHODS: Peripheral blood samples from the patients and her family members were collected for the extraction of genomic DNA. Sanger sequencing, real-time quantitative PCR and reverse transcriptase-PCR (RT-PCR) were carried out to detect single base mutation, small insertion and deletion, and large fragment deletion of the VHL gene. RESULTS: Real-time quantitative PCR combined with sequencing of RT-PCR product showed that there was a single-copy deletional germline mutation in exon 2 of the VHL gene in the proband. CONCLUSION: Loss of heterozygosity in exon 2 of the VHL gene probably underlay the etiology of familial renal cell carcinoma in this pedigree. Screening for germline mutations of the VHL gene can effectively predict the prognosis of individual patients.

The Leaf Economics Spectrum Constrains Phenotypic Plasticity Across a Light Gradient.

The leaf economics spectrum (LES) characterizes multivariate correlations that confine the global diversity of leaf functional traits onto a single axis of variation. Although LES is well established for traits of sun leaves, it is unclear how well LES characterizes the diversity of traits for shade leaves. Here, we evaluate LES using the sun and shade leaves of 75 woody species sampled at the extremes of a within-canopy light gradient in a subtropical forest. Shading significantly decreased the mean values of LMA and the rates of photosynthesis and dark respiration, but had no discernable effect on nitrogen and phosphorus content. Sun and shade leaves manifested the same relationships among N mass, P mass, A mass, and R mass (i.e., the slopes of log-log scaling relations of LES traits did not differ between sun and shade leaves). However, the difference between the normalization constants of shade and sun leaves was correlated with functional trait plasticity. Although the generality of this finding should be evaluated further using larger datasets comprising more phylogenetically diverse taxa and biomes, these findings support a unified LES across shade as well as sun leaves.

Convergent nitrogen-phosphorus scaling relationships in different plant organs along an elevational gradient.

A general relationship between the nitrogen (N) and phosphorus (P) content of all plant organs (e.g. leaf, stem, and root) is hypothesized to exist according to whole-plant economics spectrum (PES) theory, but the evidence supporting these expected patterns remains scarce. We measured the N and P content of the leaves, twigs and fine roots of 64 species in three different forest communities along an elevational gradient (evergreen broad-leaved forest, 1319 m a.s.l., coniferous and broad-leaved mixed forest, 1697 m a.s.l., and deciduous forest, 1818 m a.s.l.) in the Wuyishan National Nature Reserve, southeastern China. The scaling relationship between the N and P content and the linear regression relationship between the N:P ratio and N and P content were analysed. The leaf N and P content was significantly higher at the high-elevation site than at the low- or middle-elevation sites (P < 0.001). The N and P content followed a power-law relationship with similar scaling slopes between organs. The N (common slope, 1.13) and P (common slope, 1.03) content isometrically covaried among leaves, twigs and roots. The scaling exponents of the N-P relationship were not significantly different from 1.0 in all organs, with a common slope of 1.08. The scaling constants of N-P decreased significantly (P < 0.05) from the highest value in fine roots (ß = 1.25), followed by leaves (ß = 1.17), to the lowest value in twigs (ß = 0.88). Standardized major axis (SMA) analyses and comparisons of 95 % confidence intervals also showed that the numerical values of the scaling slopes and the scaling constants did not differ regardless of elevation. The N content, but not the P content, accounted for a large proportion of the variation in the N:P ratio in leaves (N:P and N: r 2 = 0.31, F = 33.36, P < 0.001) and fine roots (N:P and N: r 2 = 0.15, F = 10.65, P < 0.05). In contrast, the N:P ratio was significantly related to both the N and P content in the twigs (N:P and N: r 2 = 0.20, F = 17.86, P < 0.001; N:P and P: r 2 = 0.34, F = 35.03, P < 0.001, respectively). Our results indicate that different organs of subtropical woody plants share a similar isometric scaling relationship between their N and P content, providing partial support for the PES hypothesis. Moreover, the effects of the N and P content on the N:P ratio differ between metabolic organs (leaves and fine roots) and structural organs (twigs), elucidating the stoichiometric regulatory mechanism of different organs.

[Heritability of obesity in children aged 30-36 months and an analysis of single nucleotide polymorphisms at four loci in Xi'an, China].

OBJECTIVE: To study the heritability of obesity in children aged 30-36 months in Xi'an, China, as well as the role of four single nucleotide polymorphisms (SNPs) associated with body mass index in the susceptibility to obesity in children. METHODS: Random sampling was performed to select 1 637 children, aged 30-36 months, from four communities of Xi'an from March 2017 to December 2018. Physical assessment was performed for these children, and a questionnaire survey was conducted for parents. Then the Falconer regression method was used to calculate the heritability of childhood obesity. Venous blood samples were collected from 297 children who underwent biochemical examinations, among whom there were 140 children with obesity/overweight (obesity/overweight group) and 157 with normal body weight (normal body weight group). The MassARRAY RS1000 typing technique was used to detect CDKAL1 gene rs2206734, KLF9 gene rs11142387, PCSK1 gene rs261967, and GP2 gene rs12597579. The distribution of alleles and genotypes was compared between the obesity/overweight and normal body weight groups. An unconditional logistic regression model was used to investigate the benefits of dominant and recessive genetic models. RESULTS: For the 1 637 children, the heritability of obesity from the parents was 83%±8%, and the heritability from mother was slightly higher than that from father (86%±11% vs 78%±12%). There were significant differences in the distribution of rs2206734 alleles and genotypes and rs261967 genotypes between the obesity/overweight and normal body weight groups (P<0.0125). The children carrying T allele at rs2206734 had a significantly higher risk of obesity than those carrying CC (OR=0.24, P<0.0125), and the children carrying GG at rs261967 had a significantly higher risk of obesity than those carrying A allele (OR=4.11, P<0.0125). CONCLUSIONS: Genetic factors play an important role in the pathogenesis of obesity in children, and the SNPs of CDKAL1 rs2206734 and PCSK1 rs261967 are associated with the susceptibility to obesity in children aged 30-36 months in Xi'an.

[Effects of the current-year shoot stem configuration on leaf biomass in different canopy heights of woody plants in evergreen broad-leaved forest in Jiangxi Province, China.] / æ±Ÿè¥¿å¸¸ç»¿é˜”å¶æž—æœ¨æœ¬æ¤ç‰©ä¸åŒå† å±‚é«˜åº¦å½“å¹´ç”Ÿå°æžèŒŽæž„åž‹å¯¹å¶ç”Ÿç‰©é‡çš„å½±å“.

To investigate the effects of stem configuration on leaf biomass allocation in different organs of the current-year shoots at different canopy heights, relationships of biomass in different organs (i.e., leaves, stems, and twigs) and stem configuration (i.e., stem diameter, length, width/length, stem volume and stem density) were analyzed using the data of 69 woody species from the Yangjifeng Natural Reserve, Jiangxi Provence. Standardized major axis (SMA) was used to explore the regression between biomass and stem configuration. The results showed that there was no significant difference in leaf biomass, stem biomass, twig biomass, stem diameter, stem length, stem width/length and stem volume of current year shoots from upper and lower canopy heights and life forms (i.e., evergreen and deciduous woody plants). Stem density differed significantly in the current year shoots at different heights for both evergreen and deciduous woody species. There were isometric relationships among leaf, stem and total biomass of shoots in different canopy heights and in different life forms. Leaf biomass scaled allometrically with stem diameter and volume, with the scaling exponents being not different significantly among different canopy heights. With respect to the stem configuration of the twigs, stem length, stem width/length and stem density contributed less than 24% to the leaf biomass variation in the current-year shoots. On the contrary, stem diameter and volume had greater effects on leaf biomass of the current-year shoots than stem length, stem width/length and stem density. Canopy heights did not significantly affect the allometric scaling relationships between the stem configuration and leaf biomass of the current-year shoots.