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The k -ary n -cube, denoted Q n k , has the vertex set V n k = { 0 , 1 , ... , k − 1 } n , and two vertices (x 1 , x 2 , x 3 , ... , x n) and (y 1 , y 2 , y 3 , ... , y n) in V n k are adjacent if and only if there is an integer j with 1 ≤ j ≤ n such that x j ≡ y j ± 1 (mod k) and x i = y i for all i ∈ { 1 , 2 , ... , n } ∖ { j }. Let λ (F) be the vertex Turán density of a graph G for a family of forbidden configurations F. Let F 1 = { (0 , 0 , 0) , (1 , 0 , 0) , (0 , 1 , 0) , (0 , 0 , 1) } , F 2 = { (0 , 0 , 0) , (1 , 1 , 0) , (1 , 0 , 1) , (0 , 1 , 1) } , F 3 = { (0 , 0 , 0) , (1 , 1 , 1) } , F d , t , k = { F ⊆ V d k : | F | = t } , and μ (d , k) = max { t : λ (F d , t , k) = 0 }. Johnson and Talbot (2010) determined λ (F i) for i ∈ { 1 , 2 , 3 } and the bounds of μ (d , 2) in Q n 2 (where Q n 2 is the n -dimensional hypercube Q n). In this paper, we derive the exact value λ (F i) for i ∈ { 1 , 2 , 3 } in Q n 3 and determine the bounds of μ (d , k) in Q n k for any k ≥ 3. Furthermore, we consider the forbidden configurations D i = { x ∈ V 3 k : | x | = 0 or | x | = i }. The bounds of λ (D i) in Q n k are derived for any i ∈ { 1 , 2 , 3 } and k ≥ 2 , and λ (G d) = 2 / 3 in Q n 3 is derived, where G d = { x ∈ V d 3 : | x | = 0 , (| x | = 1 , qsupp (x) = i [ 1 ] ) and (| x | = 2 , qsupp (x) = { i [ 1 ] , j [ 1 ] } , i ⁄ ≡ j (mod 2)) } (see Definition 1 for qsupp (x)). [ABSTRACT FROM AUTHOR]

In this paper, we study an inverse source problem for the Helmholtz equation from measurements. The purpose of this paper is to reconstruct the salient features of the hidden sources within a body. We propose three stable reconstruction algorithms to detect the number, the location, the size, and the shape of the hidden sources along with compact support from a single measurement of near-field Cauchy data on the external boundary. This problem is nonlinear and ill-posed; thus, we should consider regularization techniques in reconstruction algorithms. We give several numerical experiments to demonstrate the viability of our proposed reconstruction algorithms. [ABSTRACT FROM AUTHOR]

Developing a highly active, acid-resistant and low-cost catalyst which can perform well in aqueous solution has long been sought for practical and sustainable lignocellulosic biomass transformation. In this work, a series of Ce–P–Co heterogeneous catalysts were prepared by a convenient solvothermal method for catalytic hydrogenation of levulinic acid (LA) to gamma-valerolactone (GVL) in water. By comprehensive characterizations and catalytic measurements, the structure of the prepared Ce–P–Co samples was disclosed as (CePO4)m/Co2P composites with a modulated molar ratio (m) of 0.04–0.34. With the introduction of CePO4, the unique hydrogen activation on CePO4 markedly accelerated the reaction, with the GVL yield after 90 min on (CePO4)m/Co2P (45–97%) being much higher than on pure Co2P (26%), together with an attractive TOF of 0.27–0.61 s−1 on (CePO4)m/Co2P (comparable to precious metal catalysts). Further analysis of the kinetic and acidic features indicated a Langmuir–Hinshelwood mechanism, initiated by activation of H2 and LA on CePO4 and Co2P, respectively, followed by a surface reaction of the two activated species as the rate-determining step, as a plausible pathway for producing GVL from LA on (CePO4)m/Co2P. The consistent catalytic performance during recycling tests and the unchanged morphological, bulk and surface structure features of the used catalyst relative to the fresh catalyst confirmed that the (CePO4)m/Co2P structure was robust enough to endure the acidic aqueous environment for efficiently and sustainably converting LA to GVL. The advantages of high catalytic efficiency, stable, acid-resistant structure and low cost marked (CePO4)m/Co2P as a competitive and practical heterogeneous catalyst for sustainable, scaled-up lignocellulosic biomass transformation. [ABSTRACT FROM AUTHOR]

At present, the colorectal cancer (CRC) is a malignant tumor of the colon and rectum that is often found at the junction of the two, and it will invade many visceral organs and organizations, causing very serious damage to the body of the patient. Patrinia villosa Juss. (P.V), is a well-known traditional chinese medicine (TCM), and is recorded in the Compendium of Materia Medica as a necessary article for the treatment of intestinal carbuncle. It has been incorporated into traditional cancer treatment prescriptions in modern medicine. While the mechanism of action of P.V in the treatment of CRC remains unclear. Aim of the study: To investigate P.V in treating CRC and clarify the underlying mechanism. This study was based on Azoxymethane (AOM) combined with the Dextran Sulfate Sodium Salt (DSS)-induced CRC mouse model to clarify the pharmacological effects of P.V. The mechanism of action was found by metabolites and metabolomics. The rationality of metabolomics results was verified through the clinical target database of network pharmacology, and find the upstream and downstream target information of relevant action pathways. Apart from that, the targets of associated pathways were confirmed, and the mechanism of action was made clear, using quantitative PCR (q-PCR) and Western blot. The number and the diameter of tumors were decreased when mice were treated with P.V. P.V group section results showed newly generated cells which improved the degree of colon cell injury. Pathological indicators presented a trend of recovery to normal cells. Compared to the model group, P.V groups had significantly lower levels of the CRC biomarkers CEA, CA19-9, and CA72-4. Through the evaluation of metabolites and metabolomics, it was found that a total of 50 endogenous metabolites had significant changes. Most of these are modulated and recovered after P.V treatment. It alters glycerol phospholipid metabolites, which are closely related to PI3K target, suggesting that P.V can treat CRC though the PI3K target and PI3K/Akt signaling pathway. q-PCR and Western blot results also verified that the expression of VEGF, PI3K, Akt, P38, JNK, ERK1/2, TP53, IL-6, TNF- α and Caspase-3 were significantly decreased, whereas that of Caspase-9 was increased after treatment. P.V is dependent on PI3K target and PI3K/Akt signaling pathway for CRC treatment. [Display omitted] • Patrinia villosa has a certain therapeutic effect on the CRC. • Patrinia villosa could up-regulate in 41 kinds, including sn-glycero-3-Phosphocholine, 1-Acyl-sn-glycero-3-phosphocholine, Diacylglycerol, etc. And down-regulate in 9 kinds, including Phytosphingosine, etc. These changes are mainly related to glycerophospholipid metabolism, sphingolipid metabolism, cysteine and methionine metabolism, glycine, serine and threonine metabolism. • Patrinia villosa treat CRC though the PI3K target and PI3K/Akt signaling pathway. • Patrinia villosa reduced the protein expression of PI3K, Akt, VEGFA, P38, JNK, ERK1/2, TP53, IL-6, TNF- α , Caspase-3, and VEGFA and increased the protein expression of Caspase-9. [ABSTRACT FROM AUTHOR]

[Display omitted] • Significant differences in cultivable yeast diversity between different honeycombs. • R. toruloides was isolated from honeybee-related products for the first time. • Lipid concentration and biomass reached 24.41 g/L and 36.78 g/L from 120 g/L glucose. • Biodiesel yield achieved as high as 93.15% from R. toruloides C23. • Transcriptome revealed hub genes involved in high biomass and high lipid production. Oleaginous yeasts-derived microbial lipids provide a promising alternative feedstock for the biodiesel industry. However, hyperosmotic stress caused by high sugar concentration during fermentation significantly prevents high cell density and productivity. Isolation of new robust osmophilic oleaginous species from specific environment possibly resolves this issue to some extent. In this study, the cultivable yeast composition of honeycombs was investigated. Totally, 11 species of honeycomb-associated cultivable yeast were identified and characterized. Among them, an osmophilic yeast strain, designated as Rhodotorula toruloides C23 was featured with excellent lipogenic and carotenogenic capacity and remarkable cell growth using glucose, xylose or glycerol as feedstock, with simultaneous production of 24.41 g/L of lipids and 15.50 mg/L of carotenoids from 120 g/L glucose in 6.7-L fermentation. Comparative transcriptomic analysis showed that C23 had evolved a dedicated molecular regulation mechanism to maintain their high simultaneous accumulation of intracellular lipids and carotenoids and cell growth under high sugar concentration. [ABSTRACT FROM AUTHOR]

The interrelationship among genetic variations between the developing process of carcinoma and the order of occurrence has not been completely understood. Interpreting the mechanisms of copy number variation (CNV) is absolutely necessary for understanding the etiology of genetic disorders. Oncogenetic tree is a special phylogenetic tree inferential pictorial representation of oncogenesis. In our present study, we constructed oncogenetic tree to imitate the occurrence of genetic and cytogenetic alterations in human breast cancer. The oncogenetic tree model was built on CNV of ErbB2, AKT2, KRAS, PIK3CA, PTEN, and CCND1 genes in 963 cases of tumors with sequencing and CNA data of human breast cancer from TCGA. Results from the oncogenetic tree model indicate that ErbB2 copy number variation is the frequent early event of human breast cancer. The oncogenetic tree model based on the phylogenetic tree is a type of mathematical model that may eventually provide a better way to understand the process of oncogenesis. [ABSTRACT FROM AUTHOR]

Selenium (Se) plays a critical role in diverse biological processes and is widely used across manufacturing industries. However, the contamination of Se oxyanions also poses a major public health concern. Microbial transformation is a promising approach to detoxify Se oxyanions and produce elemental selenium nanoparticles (SeNPs) with versatile industrial potential. Yeast-like fungi are an important group of environmental microorganisms, but their mechanisms for Se oxyanions reduction remain unknown. In this study, we found that Aureobasidium melanogenum I15 can reduce 1.0 mM selenite by over 90% within 48 h and efficiently form intracellular or extracellular spherical SeNPs. Metabolomic and proteomic analyses disclosed that A. melanogenum I15 evolves a complicated selenite reduction mechanism involving multiple metabolic pathways, including the glutathione/glutathione reductase pathway, the thioredoxin/thioredoxin reductase pathway, the siderophore-mediated pathway, and multiple oxidoreductase-mediated pathways. This study provides the first report on the mechanism of selenite reduction and SeNPs biogenesis in yeast-like fungi and paves an alternative avenue for the bioremediation of selenite contamination and the production of functional organic selenium compounds. [Display omitted] • melanogenum I15 can reduce over 90% of 1 mM selenite within 48 h. • Selenite reduction occurs both intracellularly and extracellularly in I15. • Selenite reduction occurs through multiple oxidoreductase-mediated pathways in I15. • Selenite stress alters the cell morphology and the cell membrane structure of I15. • Glutathione and siderophores were actively involved in the selenite reduction of I15. [ABSTRACT FROM AUTHOR]

Abstract: Sludge samples were collected from different treatment steps of Gaobeidian wastewater treatment plant (WWTP) of Beijing City, PR China, to investigate the distributions of total and chemical fractions of Fe, Mn, Ni, Cu, Zn, Cr, Pb, and Mo in different sludges. The highest total concentrations were found for Fe, Mn, Pb, and Mo in digested sludge (DS), Ni and Cr in thickened sludge (TS), Zn in dewatering sludge (DWS), and Cu in active sludge (AS). The lowest concentrations were observed in AS, except for Cu in TS. Significant differences of total metal concentration were observed between AS and TS (or DS), suggesting that sludge thickening and digesting treatments significantly influenced the total metal concentrations. Fe, Cu, Ni, Cr, Mo, and Pb distributed principally in the residual fraction in all sludges, while Zn and Mn presented in a highly available fraction. For same metal in different sludges, the portion of easily mobile fraction decreased significantly along the wastewater treatment process, and metals in AS presented in the highest available fraction. Organic matter contents, TN, and TP of sludges exhibited a significant positive correlation with the concentrations of exchangeable and reducible fraction of Pb, Mo, Cr, Cu, and Fe, while sludge pH demonstrated significant negative correlations with the concentrations of these metals. [Copyright &y& Elsevier]

Since the Anthropocene, biodiversity loss owing to human activity and climate change has worsened. Quercus gilva is an evergreen oak species native to China, Japan, and South Korea and is threatened by a long history of human impact. The purpose of this study was to (1) reassess the threatened category of Q. gilva based on a detailed survey, and (2) identify the genetic structure and diversity of Q. gilva based on genomic data. First, we conducted a detailed survey of the populations in China. Second, we collated all the literature and information. Finally, genome-wide genetic variation was analyzed based on 65 individuals from 22 populations. We found that Q. gilva has suffered rapid population decline, and at present, most populations are very small. The evolutionary path of Q. gilva was from the southwest to east of China and then to Japan and South Korea. Quercus gilva showed no distinct genetic structure and had a relatively low genetic diversity. Among the 22 populations, most populations in southwestern China, South Korea, and Japan had high genetic diversity. The populations in Jingning (Zhejiang province; ZJN), Wuyuan (Jinaxi province; JWY), and Zherong (Fujian province; FZR) suffered a strong bottleneck. In conclusion, Q. gilva is an endangered species native to East Asia. Because of the very low genetic diversity of Q. gilva and most populations are small, we need to (1) strengthen the protection of this species, (2) conduct conservation actions with in-situ reinforcement populations, and (3) select populations with high genetic diversity as provenances for afforestation efforts. Finally, we suggest that in the future, genetic diversity should be considered as the sixth criterion for IUCN to evaluate the threatened category. [ABSTRACT FROM AUTHOR]

Abstract: A series of novel 1,2,3-triazole–dithiocarbamate–urea hybrids were designed, synthesized and their antiproliferative activities against four selected human cancer cell lines were evaluated. The results showed that a number of the hybrids exhibited potent activity in selected human cancer cell lines. Among them, compounds 27 and 34 showed broad spectrum anticancer activity with IC50 values ranging from 1.62 to 20.84 μM and 0.76 to 13.55 μM, respectively. Interestingly, compounds 27 and 34, being very potent against MGC-803 cells, exhibited no significant cytotoxicity against normal human embryonic kidney cells at up to 55 μM and 70 μM, respectively. Evidences of cell cycle arrest and apoptosis induction were obtained for the most effective compounds 27 and 34 by means of flow cytometry and microscopic techniques. [Copyright &y& Elsevier]

To assess the value of parameters of myocardial work for dynamic monitoring of myocardial injury after neonatal asphyxia. Fifty-three neonates with asphyxia admitted within 24 h after delivery were divided into a mild asphyxia group (n = 40) and severe asphyxia group (n = 13). Echocardiography was performed within 24 h post-birth, within 72 h post-birth (48 h after first echo), and during recovery. The left ventricular ejection fraction on M-mode echocardiography and by Simpson’s biplane method (LVEF and Bi-EF, respectively), stroke volume (SV), cardiac output (CO), cardiac index (CI), global longitudinal strain (GLS), global work index (GWI), global constructive work (GCW), and other parameters were measured. Echocardiographic indicators were compared between groups and over time. GWI was significantly increased at 72 h in the mild asphyxia group (P < 0.05) but showed no significant change over time in the severe asphyxia group (P > 0.05). While GCW increased significantly over time in both groups (P < 0.05), it increased earlier in the mild asphyxia group. Time and grouping factors had independent effects on GWI and GCW (P > 0.05). The characteristics of differences in GWI and GCW between the two groups were different from those for LVEF, Bi-EF, SV, CO, CI, and GLS and their change characteristics with improvement from treatment. GWI and GCW changed significantly during recovery from neonatal asphyxia, and their change characteristics differed between mild and severe asphyxia cases. Myocardial work parameters can be used as valuable supplements to traditional indicators of left ventricular function to dynamically monitor the recovery from myocardial injury after neonatal asphyxia. [ABSTRACT FROM AUTHOR]

Background: The number of coronavirus disease 2019 (COVID-19) cases has rapidly increased all over the world. Specific information about immunity in non-survivors with COVID-19 is scarce. This study aimed to analyse the clinical characteristics and abnormal immunity of the confirmed COVID-19 non-survivors. Methods: In this single-centered, retrospective, observational study, we enrolled 125 patients with COVID-19 who were died between January 13 and March 4, 2020 in Renmin Hospital of Wuhan University. A total of 414 randomly recruited patients with confirmed COVID-19 who were discharged from the same hospital during the same period served as control. The demographic, clinical characteristics and laboratory findings at admission, and treatment used in these patients were collected. The immunity-related risk factors associated with in-hospital death were tested by logistic regression models and Receiver Operating Characteristic (ROC) curve. Results: Non-survivors (70 years, IQR: 61.5–80) were significantly older than survivors (54 years, IQR: 37–65) (P < 0.001). 56.8% of non-survivors was male. Nearly half of the patients (44.9%) had chronic medical illness. In non-survivors, hypertension (49.6%) was the most common comorbidity, followed by diabetes (20.0%) and coronary heart disease (16.0%). The common signs and symptoms at admission of non-survivors were fever (88%), followed by cough (64.8%), dyspnea (62.4%), fatigue (62.4%) and chest tightness (58.4%). Compared with survivors, non-survivors had higher white blood cell (WBC) count (7.85 vs 5.07 × 109/L), more elevated neutrophil count (6.41 vs 3.08 × 109/L), smaller lymphocyte count (0.69 vs 1.20 × 109/L) and lower platelet count (172 vs 211 × 109/L), raised concentrations of procalcitonin (0.21 vs 0.06 ng/mL) and CRP (70.5 vs 7.2 mg/L) (P < 0.001). This was accompanied with significantly decreased levels of CD3+ T cells (277 vs 814 cells/μl), CD4+ T cells (172 vs 473 cells/μl), CD8+ T cells (84 vs 262.5 cells/μl, P < 0.001), CD19+ T cells (88 vs 141 cells/μl) and CD16+ 56+ T cells (79 vs 128.5 cells/μl) (P < 0.001). The concentrations of immunoglobulins (Ig) G (13.30 vs 11.95 g/L), IgA (2.54 vs 2.21 g/L), and IgE (71.30 vs 42.25 IU/ml) were increased, whereas the levels of complement proteins (C)3 (0.89 vs 0.99 g/L) and C4 (0.22 vs 0.24 g/L) were decreased in non-survivors when compared with survivors (all P < 0.05). The non-survivors presented lower levels of oximetry saturation (90 vs 97%) at rest and lactate (2.40 vs 1.90 mmol/L) (P < 0.001). Old age, comorbidity of malignant tumor, neutrophilia, lymphocytopenia, low CD4+ T cells, decreased C3, and low oximetry saturation were the risk factors of death in patients with confirmed COVID-19. The frequency of CD4+ T cells positively correlated with the numbers of lymphocytes (r = 0.787) and the level of oximetry saturation (r = 0.295), Whereas CD4+ T cells were negatively correlated with age (r =-0.323) and the numbers of neutrophils (r = − 0.244) (all P < 0.001). Conclusions: Abnormal cellular immunity and humoral immunity were key features of non-survivors with COVID-19. Neutrophilia, lymphocytopenia, low CD4+ T cells, and decreased C3 were immunity-related risk factors predicting mortality of patients with COVID-19. [ABSTRACT FROM AUTHOR]

The nanocomposites of Co nanoparticles with composition-adjustable Co X N composited on surface in carbon coverage (Co@Co x N@C) were feasibly prepared upon a dual-ligand MOF manipulating strategy, the highly dispersed Co x N on Co matrix was quite efficient for activating C O and lowering the reaction activation energy (Ea), leading to the superior TOF and yield for selective hydrogenation of citral to nerol and geraniol. • Efficient and stable Co@Co x N@C nanocomposite catalysts for citral hydrogenation were feasibly acquired from a dual-ligand-MOF manipulating strategy. • The composition of exposed Co x N could be conveniently adjusted from the strategy. Interstitial compounds with tunable surface properties are highly desirable for advanced applications. Here, we present a dual-ligand-metal-organic framework (MOF) strategy to synthesize Co N C catalysts for the selective hydrogenation of citral. The dual-ligand MOF was synthesized by coordinating Co with both a N-donor ligand and a benzenedicarboxylic acid ligand, and calcining in a N 2 atmosphere at 973, 1073, or 1173 K. The Co N C catalysts derived from this strategy were Co nanoparticles (10.0–20.0 nm in diameter) with composite Co/Co x N surfaces covered in a layer of carbon (Co@Co x N@C). The highest Co x N surface composition, 0.54, was achieved when the precursor was calcined at 1073 K; this catalyst exhibited 100% citral conversion with 98% selectivity for the desired products (up to 60% selectivity for the most valuable C O hydrogenation product) and a superior turnover frequency (TOF) of 0.56 s−1. In-situ IR spectra and kinetic investigations were used to confirm that the exposed Co x N on the Co@CoxN@C nanostructures contributed to activating the C O bond and facilitating the transformation of citral to the desired C O hydrogenation products. The results of this study suggest that this dual-ligand-MOF strategy could be used to construct efficient interstitial compounds for advanced applications. [ABSTRACT FROM AUTHOR]

Pyroptosis is triggered by inflammasomes after its activation by various inflammatory stimulations, including lipopolysaccharide (LPS) and improper pH. This may result in programmed death of the affected cell. It is well known that NLRP1 and NLRP3 inflammasomes mediate the production of various cytokines in inflammatory disorders; however, it is still unknown whether NLRP1 and NLRP3 inflammasomes can influence the LPS‑induced pyroptosis in the progression of knee osteoarthritis (KOA). In the present study, the correlation between the NLRP inflammasomes and fibroblast‑like synoviocytes (FLSs) pyroptosis was investigated in vivo and in vitro. Human synovial samples were collected from KOA patients and the expression of NLRP1 and NLRP3 inflammasomes was analyzed. Human FLS were isolated in vitro and stimulated with LPS. To determine whether NLRP1 and NLRP3 inflammasomes are involved in FLS pyroptosis, NLRP1 and NLRP3 small interfering RNAs (siRNAs) were used. The results showed that the expression of NLRPs and inflammasome‑related proteins were upregulated and FLS stimulated with LPS+ATP resulted in cell pyroptosis. However, LPS+ATP‑induced pyroptosis was attenuated by NLRP1 and NLRP3 siRNAs. The results of the present study indicate that LPS‑induced FLS pyroptosis may be mediated by either NLRP1 or NLRP3 inflammsomes. Overall, based on the data obtained from patients and in vitro cells, the present finsings showed that NLRP1 and NLRP3 inflammasomes are highly involved in the FLS inflammation and pyroptosis. Furthermore, inhibition of NLRP1 and NLRP3 led to a remarkable reduction of pyroptosis‑related cytokines. Thus, NLRP1 and NLRP3 inflammasomes may be important in the pathogenesis of OA and may represent a novel therapeutic target. [ABSTRACT FROM AUTHOR]

Cloning remains as an important technique to enhance the reconstitution and distribution of animal population with high-genetic merit. One of the major detrimental factors of this technique is the abnormal epigenetic modifications. MGCD0103 is known as a histone deacetylase inhibitor. In this study, we investigated the effect of MGCD0103 on the in vitro blastocyst formation rate in porcine somatic cell nuclear transferred (SCNT) embryos and expression in acetylation of the histone H3 lysine 9 and histone H4 lysine 12. We compared the in vitro embryonic development of SCNT embryos treated with different concentrations of MGCD0103 for 24 hours. Our results reported that treating with 0.2-μM MGCD0103 for 24 hours effectively improved the development of SCNT embryos, in comparison to the control group (blastocyst formation rate, 25.5 vs. 10.7%, P < 0.05). Then we tested the in vitro development of SCNT embryos treated with 0.2-μM MGCD0103 for various intervals after activation. Treatment for 6 hours significantly improved the development of pig SCNT embryos, compared with the control group (blastocyst formation rate, 21.2 vs. 10.5%, P < 0.05). Furthermore, MGCD0103 supplementation significantly (P < 0.05) increases the average fluorescence intensity of AcH3K9 and AcH4K12 in embryos at the pseudo-pronuclear stage. To examine the in vivo development, MGCD0103-treated SCNT embryos were transferred into two surrogate sows, one of whom became pregnant and three fetuses developed. These results suggest that MGCD0103 can enhance the nuclear reprogramming and improve in vitro developmental potential of porcine SCNT embryos. [ABSTRACT FROM AUTHOR]

The influence of topography and Pleistocenic climatic fluctuations on the population genetic structure of amphibians in the Tsinling-Dabieshan Mountains of China is poorly investigated.Hyla tsinlingensisis a tree frog endemic to the Tsinling-Dabieshan Mountains, with a restricted and patchy distribution that is currently shrinking. We speculated on the evolutionary history of amphibians in this region by studying the population genetic structure ofH. tsinlingensis.Using a total of 212 samples, 32 haplotypes and four haplogroups were found in the present study. Population genetic structure showed significant differentiation (FST) between most populations ofH. tsinlingensisin the Tsinling-Dabieshan Mountains. An analysis of molecular variance (AMOVA) suggested that most of the observed genetic variation occurs between the two regions (the Tsinling and Dabieshan Mountains). Mantel tests indicated that the genetic divergence was induced through isolation by distance. Using Monmonier's maximum difference algorithm to predict the genetic barrier, two putative barriers in gene flow that separate lineages ofH. tsinlingensiswere identified. Mismatch distribution and neutrality tests found a sudden population expansion in all haplogroups except the Tsinling population and total population. This population expansion was identified between 0.5 Myr to 0.1 Myr (Quaternary) by Bayesian skyline plot (BSP). Divergence dating indicated the divergence time between the Tsinling population and Dabieshan population to be 3.26 MYA (Pliocene). In conclusion, the topography of the Tsinling and Dabieshan Mountains exerts a significant impact on the population genetic structure ofH. tsinlingensis,and climatic oscillations during glacial periods in the Quaternary affected the distribution ofH. tsinlingensis. [ABSTRACT FROM AUTHOR]

Sediment cores were sampled from three typical shallow urban lakes in China. The Standards, Measurements and Testing (SMT) programme, proposed by the European Commission, was employed to characterize the vertical distributions of phosphorus fractions in sediment profiles. The results showed that TP contents ranged from 1,198.9 to 1,897.3, 1,289.1 to 1,652.1, and 611.7 to 760.3 mg kg-1 in sediment profiles of Daming Lake, Mochou Lake, and Xuanwu Lake, respectively. Within the 50-cm sediment profiles, phosphorus distributed mainly in IP, and the OP contents only accounted for 9.7%¨16.3% of TP. For IP in sediments, the AP was the predominant fraction for Daming Lake and Mochou Lake, accounting for 92.8%, and 71.4%, respectively. While for Xuanwu Lake the proportion of NAIP to IP was higher than that of AP (41.7%±6.0%), indicating that the Xuanwu Lake was polluted more heavily than the other two lakes. The phosphorus concentration in pore-water (TDP) correlated significantly to the P fractions in sediments, especially to the OP and NAIP contents, which could be predicted by: TDP (mg L-1) = 0.005 OP (mg kg-1) - 0.001 NAIP (mg kg-1) + 0.138 (R2 = 0.836, P<0.01). The physicochemical properties of sediments presented significant correlation to the contents of P fractions, highlighting the importance of the physicochemical properties of sediments for the phosphorus fraction distributions in lake sediments. [ABSTRACT FROM AUTHOR]