TIMELESS promotes reprogramming of glucose metabolism in oral squamous cell carcinoma.

BACKGROUND: Oral squamous cell carcinoma (OSCC), the predominant malignancy of the oral cavity, is characterized by high incidence and low survival rates. Emerging evidence suggests a link between circadian rhythm disruptions and cancer development. The circadian gene TIMELESS, known for its specific expression in various tumors, has not been extensively studied in the context of OSCC. This study aims to explore the influence of TIMELESS on OSCC, focusing on cell growth and metabolic alterations. METHODS: We analyzed TIMELESS expression in OSCC using western blot, immunohistochemistry, qRT-PCR, and data from The Cancer Genome Atlas (TCGA) and the Cancer Cell Line Encyclopedia (CCLE). The role of TIMELESS in OSCC was examined through clone formation, MTS, cell cycle, and EdU assays, alongside subcutaneous tumor growth experiments in nude mice. We also assessed the metabolic impact of TIMELESS by measuring glucose uptake, lactate production, oxygen consumption, and medium pH, and investigated its effect on key metabolic proteins including silent information regulator 1 (SIRT1), hexokinase 2 (HK2), pyruvate kinase isozyme type M2 (PKM2), recombinant lactate dehydrogenase A (LDHA) and glucose transporter-1 (GLUT1). RESULTS: Elevated TIMELESS expression in OSCC tissues and cell lines was observed, correlating with reduced patient survival. TIMELESS overexpression enhanced OSCC cell proliferation, increased glycolytic activity (glucose uptake and lactate production), and suppressed oxidative phosphorylation (evidenced by reduced oxygen consumption and altered pH levels). Conversely, TIMELESS knockdown inhibited these cellular and metabolic processes, an effect mirrored by manipulating SIRT1 levels. Additionally, SIRT1 was positively associated with TIMELESS expression. The expression of SIRT1, HK2, PKM2, LDHA and GLUT1 increased with the overexpression of TIMELESS levels and decreased with the knockdown of TIMELESS. CONCLUSION: TIMELESS exacerbates OSCC progression by modulating cellular proliferation and metabolic pathways, specifically by enhancing glycolysis and reducing oxidative phosphorylation, largely mediated through the SIRT1 pathway. This highlights TIMELESS as a potential target for OSCC therapeutic strategies.

HER2/ ERBB2 Immunohistochemical Expression and Copy Number Status in Ovarian Mucinous Tumors.

Primary mucinous ovarian carcinoma (MOC) is a rare ovarian epithelial cancer, which is often refractory to chemotherapy. HER2-targeting therapy is being increasingly considered in gynecologic malignancies. Although there have been limited studies examining the HER2 status of such tumors, the criteria for HER2 expression scoring have not been standardized for MOC as it has for other sites. This study aimed to survey immunohistochemical HER2 expression patterns in MOC and its precursor, mucinous borderline tumor in correlation with fluorescence in situ hybridization (FISH). Immunohistochemistry (IHC) for HER2 was performed on 12 cases of MOC and 15 mucinous borderline tumors, including 7 with intraepithelial carcinoma. HER2 expression was quantified using the gastric/gastroesophageal carcinoma protocol. Cases were considered 3+ if the tumor cells displayed strong complete or basolateral/lateral membranous staining in ≥10% of tumor cells. Cases (2+) had weak to moderate staining in ≥10% of tumor cells. Cases (1+) had faint staining in ≥10% of tumor cells. Cases considered 0 had no staining or faint staining in <10% of tumor cells. HER2 expression was also quantified with the endometrial serous carcinoma protocol, which uses a 30% tumor cell positivity cutoff. FISH for HER2 was performed on all 3+ and 2+ and a subset of 1+ cases. Of the MOC cases, 25% were 3+ and 1 mucinous borderline tumor with intraepithelial carcinoma had 3+ staining. All 3+ IHC MOC cases had >30% basolateral membranous staining. HER2 amplification was confirmed by FISH on all 3+ IHC cases and in one 2+ IHC case of MOC. Up to 25% of mucinous ovarian tumors showed HER2 IHC overexpression with an excellent correlation between IHC and FISH using the HER2 scoring protocol for either gastric/gastroesophageal carcinoma or uterine serous carcinoma.

Influence of cyclin D1 splicing variants expression on breast cancer chemoresistance via CDK4/CyclinD1-pRB-E2F1 pathway.

Cyclin D1 (CCND1), a mediator of cell cycle control, has a G870A polymorphism which results in the formation of two splicing variants: full-length CCND1 (CCND1a) and C-terminally truncated CCND1 species (CCND1b). However, the role of CCND1a and CCND1b variants in cancer chemoresistance remains unknown. Therefore, this study aimed to explore the molecular mechanism of alternative splicing of CCND1 in breast cancer (BC) chemoresistance. To address the contribution of G870A polymorphism to the production of CCND1 variants in BC chemoresistance, we sequenced the G870A polymorphism and analysed the expressions of CCND1a and CCND1b in MCF-7 and MCF-7/ADM cells. In comparison with MCF-7 cells, MCF-7/ADM cells with the A allele could enhance alternative splicing with the increase of SC-35, upregulate the ratio of CCND1b/a at both mRNA and protein levels, and activate the CDK4/CyclinD1-pRB-E2F1 pathway. Furthermore, CCND1b expression and the downstream signalling pathway were analysed through Western blotting and cell cycle in MCF-7/ADM cells with knockdown of CCND1b. Knockdown of CCND1b downregulated the ratio of CCND1b/a, demoted cell proliferation, decelerated cell cycle progression, inhibited the CDK4/CyclinD1-pRB-E2F1 pathway and thereby decreased the chemoresistance of MCF-7/ADM cells. Finally, CCND1 G870A polymorphism, the alternative splicing of CCDN1 was detected through Sequenom Mass ARRAY platform, Sanger sequencing, semi-quantitative RT-PCR, Western blotting and immunohistochemistry in clinical BC specimens. The increase of the ratio of CCND1b/a caused by G870A polymorphism was involved in BC chemoresistance. Thus, these findings revealed that CCND1b/a ratio caused by the polymorphism is involved in BC chemoresistance via CDK4/CyclinD1-pRB-E2F1 pathway.

Diallyl Trisulfide Suppresses the Renal Cancer Stem-like Cell Properties via Nanog.

Cancer stem-like cells (CSCs), which play an important role in tumor initiation and progression, have been identified in many cancers. Diallyl trisulfide (DATS) is an organosulfur compound extracted from garlic with anticancer activities. Nanog is a transcription factor responsible for maintaining the stemness of CSCs, but its role in the DATS-induced attenuation of renal CSC properties is unknown. In this study, renal CSCs were enriched from human renal cancer cell lines 786-O and ACHN cultured in a serum-free medium (SFM). The properties of CSCs were analyzed by evaluating the ability of the cells in sphere formation and measuring the expression of stem cell markers. We found that downregulation of Nanog inhibited renal CSC properties. DATS suppressed renal CSC activities by reducing tumorsphere formation, decreasing stem cell markers including Nanog, CD44, ALDH1A1, and Oct4, inhibiting cell proliferation and promoting apoptosis. We further revealed that overexpression of Nanog reversed the suppressive effects of DATS on renal CSCs. Taken together, our results demonstrated that DATS inhibited renal CSCs by suppressing Nanog. These novel findings suggested that, through Nanog targeting, DATS can potentially be used as an anti-tumor agent for renal cancer.

Segmental Abnormalities of White Matter Microstructure in Primary Hypothyroidism Identified by Automated Fiber Quantification.

INTRODUCTION: Hypothyroidism leads to impaired white matter (WM) integrity, associated with cognitive/neuropsychiatric dysfunction. However, the specific segmental abnormalities of the fibers remain unexplored. Therefore, this study aimed to investigate whether the damage of the WM is limited to a specific segment or the entire bundle via diffusion metrics using automated fiber quantification. METHODS: A cross-sectional study was conducted on 31 hypothyroid patients and 28 healthy controls. Thyroid-related hormone levels, cognitive/neuropsychiatric function, and diffusion tensor image data were collected and analyzed. Correlation and random forest analyses were also performed. RESULTS: The mean fractional anisotropy (FA) values were reduced at the fiber tract level. The mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) values were increased in several fiber tracts, i.e., cingulum cingulate (CC), anterior forceps of corpus callosum (CCF_A). Significant correlations were found between cognitive function and diffusion indicators such as the FA value of the left corticospinal tract and arcuate fasciculus (AF), the MD value of left CC, the RD value of left AF, the AD value of left CC, and CCF_A. The widespread microstructure disruption was spread on multiple specific segments of different tracts at the point-wise level. The random forest revealed that the accuracy of recognizing hypothyroid patients was 82.5%, with the anterior component of CCF_A having the most significant contribution. CONCLUSION: WM microstructural integrity impairments were found in multi-segments of the multiple fiber bundles in hypothyroidism, which might be a potential mechanism of the underlying neurocognitive decline and cerebral impairment. The CCF_A might serve as a neuro biomarker for early warning of cerebral impairment in hypothyroidism.

Impaired autophagy flux by lncRNA NEAT1 is critical for inflammation factors production in human periodontal ligament stem cells with nicotine treatment.

BACKGROUND AND OBJECTIVES: Periodontitis is the top reason for tooth loss, and smoking significantly increases severe periodontitis risk. Defective autophagy has been reported to play a vital role in periodontitis. This study aimed to elucidate the relationship between autophagy and inflammation factors production in nicotine-treated periodontal ligament stem cells (PDLSCs) and the underlying mechanism. METHODS: In this study, transmission electron microscopy, immunofluorescence, and the mCherry-GFP-LC3 plasmid were used to study autophagy flux. The gene levels of inflammation factors and long noncoding RNA nuclear paraspeckle assembly transcript 1 (lncRNA NEAT1) were detected by quantitative real-time PCR (qRT-PCR). Western blot was performed to assess the protein levels of autophagic markers and α7 nicotinic acetylcholine receptor (α7nAChR). RESULTS: We found that nicotine impaired autophagosome-lysosome fusion and lysosome functions to block autophagy flux, contributing to inflammatory factors production in nicotine-treated PDLSCs. Moreover, nicotine upregulated NEAT1 by activating α7nAChR. NEAT1 decreased autophagy flux by downregulating syntaxin 17 (STX17). CONCLUSION: Our data indicate that NEAT1-decreased autophagy flux is pivotal for inflammation factors production in nicotine-treated PDLSCs.

How social connectedness contributes to life satisfaction among Chinese nurses: Testing potential moderated mediation pathways.

AIMS: The purpose of this study was to identify the mediating and moderating mechanisms by which social connectedness predicts life satisfaction among Chinese nurses. BACKGROUND: Previous researchers have primarily focused on sociodemographic and occupational domain risk factors for nurses' life satisfaction with relatively little insight into facilitative and protective factors and underlying psychological mechanisms. METHODS: We investigated 459 Chinese nurses' social connectedness, work-family enrichment, self-concept clarity, and life satisfaction via a cross-sectional design. We explored the underlying predictive mechanisms among these variables by creating a moderated mediation model. We followed STROBE checklist. RESULTS: Work-family enrichment played a mediating role in understanding the positive effects of social connectedness on nurses' life satisfaction. In addition, the moderating effect of self-concept clarity was manifested itself in the association between work-family enrichment and life satisfaction. DISCUSSION AND CONCLUSION: Interpersonal asset (social connectedness) and the positive aspect of the work-family interface (work-family enrichment) were significant contributors to nurses' life satisfaction. In particular, high self-concept clarity can enhance the beneficial effect of work-family enrichment on life satisfaction. IMPLICATIONS FOR NURSING POLICY AND PRACTICE: Strengthening social connectedness, promoting synergy in work-family roles, and maintaining a clarity of self-concept are important intervention pathways to enhance the health and well-being of nurses.

Construct validity and psychometric properties of the Chinese version of the City Birth Trauma Scale.

BACKGROUND: Currently, most postpartum posttraumatic stress disorder (PTSD) screening scales used in China are general PTSD scales which are not compiled specifically for pregnant women and thus cannot reflect the unique needs of this population. This study aimed to translate the City Birth Trauma Scale (City BiTS) into Chinese and validate its psychometric characteristics in Chinese postpartum women. METHODS: After translation, back-translation, and expert discussion, 596 mothers at 1 to 12 months postpartum filled out the questionnaires through the Internet. The reliability and validity of the translated questionnaire were tested. RESULTS: The Cronbach's α coefficient of the Chinese version of City BiTS (City BiTS-C) was 0.889, the test-retest reliability was 0.86, and the content validity was 0.93. Exploratory factor analysis extracted two factors accounted for 63.148% of the variance. The City BiTS-C had appropriate construct validity in the Chinese culture (root mean square error of approximation [RMSEA] = 0.048, <0.05; χ2 /df = 2.666, <3). The values of the incremental fit index (IFI) and the Tucker-Lewis coefficient (TLI) were 0.990 and 0.976, which identified that the model was a good fit for the data. The values of the comparative fit index (CFI) and the normed fit index (NFI) were 0.890 and 0.873, respectively. CONCLUSIONS: The City BiTS-C is a reliable and valid measure to screening and diagnosis the postpartum PTSD among new mothers who gave birth in the past year in mainland China. IMPLICATIONS: The City BiTS-C is a short, reliable, and valid instrument that measures the symptoms of postpartum PTSD, and it is recommend for clinical screening.

Experimental study of sediment wash-off process over urban road and its dependence on particle size distribution.

Sediment originating from the urban road runoff is a main contributor to water pollution in urban areas. The size of the road sediment varies significantly, but its influence on sediment wash-off process has not been well investigated. In this study, sediments with different particle size distributions have been used in rainfall-runoff experiments over idealized urban road surface. The results show that, under the same experimental conditions, the capacity factor CF increases with the decrease of the median particle diameter D50, which is the dominant influencing factor on CF. The wash-off coefficient k is affected by both D50 and the grading of sediment. During the wash-off process, D50 of the sediment collected at the outlet increases with time. Such a grain coarsening phenomenon is particularly apparent when the road is originally covered with very fine sediments. Furthermore, the presence of coarse grains slows down the transport of fine sediment whose size is smaller than 14 µm. This shielding effect significantly affects the sediment wash-off process in the early stage of a rainfall event, while later on the interaction between particles of different sizes becomes unimportant. This study advances the understanding of sediment wash-off mechanism on urban road surface.

Resveratrol Inhibition of Renal Cancer Stem Cell Characteristics and Modulation of the Sonic Hedgehog Pathway.

AIMS: Renal cell cancers typically exhibit high metastasis and recurrence, and this is thought to be due to renal cancer stem cells (CSCs). Meanwhile, aberrant activation of Sonic hedgehog (Shh) signaling is linked with CSCs. Resveratrol has direct or indirect impacts on the pathological activities of CSCs. However, the effects of resveratrol on renal CSCs remain to be elucidated. METHODS: We cultured renal CSCs in serum-free medium. Western blotting was used to analyze the expression levels of related proteins. The mRNA changes were detected by qRT-PCR after resveratrol treatment. The CD133+ cells were quantified by flow cytometry analysis. Immunofluorescence staining images showed the changes in CD44 and Smoothened expression in the cell spheres. RESULTS: Renal CSCs were enriched by tumorsphere formation assays of ACHN and 786-O cells. Resveratrol treatments markedly decreased the size and number of cell spheres and downregulated the expression of the Shh pathway-related proteins and CSCs markers. Moreover, we observed that resveratrol inhibited cell proliferation and induced cell apoptosis, while purmorphamine upregulated the Shh pathway and weakened the effects of resveratrol on renal CSCs. CONCLUSIONS: These results suggested that resveratrol is a potential novel therapeutic agent that targets inactivation of renal CSCs by affecting the function of the Shh pathway.

Biocontrol Potential of Trichoderma afroharzianum TM24 Against Grey Mould on Tomato Plants.

Grey mould caused by Botrytis cinerea leads to severe economic loss on commercial tomato production. Application of beneficial microorganism offers an eco-friendly alternative for mitigation of tomato fungal disease damage, considering negative influences of fungicides. In the present study, an antagonistic Trichoderma afroharzianum isolate TM24 was evaluated for its biocontrol potential on tomato grey mould. The isolate TM24 showed obviously antagonistic effect on B. cinerea mycelium growth and production of glucanase and chitinase. Leaf spraying with spore suspension of isolate TM24 showed a biocontrol efficiency of over 54% against tomato grey mould in greenhouse pot experiment. The activities of plant defense-related enzymes including polyphenol oxidase, phenylalanine ammonialyase, superoxide dismutase, and peroxidase were all increased to varying degrees in tomato leaves after isolate TM24 treatment. Transcriptome analysis showed that, a total of 1941, 1753 and 38 differentially expressed genes (DEGs) were obtained at 24, 48 and 72 hpi, respectively, in tomato leaves pretreated with T. afroharzianum TM24, and then challenged with B. cinerea inoculation. The DEGs were mainly enriched in MAPK signaling pathway and plant hormones signal transduction pathway. Multiple genes that regulated crucial nodes of defense-related pathways, like flavonoid, phenylpropanoid, jasmonic acid and ethylene metabolisms were also identified, which may have positive correlations with the biocontrol potential of isolate TM24 in tomato plants. These promising results provided valuable information on using T. afroharzianum TM24 as a beneficial biocontrol agent in tomato grey mould management.

Analysis of predictors of adherent perinephric fat and its impact on perioperative outcomes in laparoscopic partial nephrectomy: a retrospective case-control study.

BACKGROUND: Adherent perinephric fat (APF), characterized by inflammatory fat surrounding the kidney, can limit the isolation of renal tumors and increase the operative difficulty in laparoscopic partial nephrectomy (LPN). The aim of this study was to investigate the predictors of APF and its impact on perioperative outcomes during LPN. METHODS: A total of 215 consecutive patients undergoing LPN for renal cell carcinoma (RCC) from January 2017 to June 2019 at our institute were included. We divided these patients into two groups according to the presence of APF. Radiographic data were retrospectively collected from preoperative cross-sectional imaging. The perioperative clinical parameters were compared between the two groups. Univariate and multivariate analyses were performed to evaluate the predictive factors of APF. RESULTS: APF was identified in 41 patients (19.1%) at the time of LPN. Univariate analysis demonstrated that APF was significantly correlated with the male gender (P = 0.001), higher body mass index (P = 0.002), lower preoperative estimated glomerular filtration rate (P = 0.004), greater posterior perinephric fat thickness (P < 0.001), greater perinephric stranding (P < 0.001), and higher Mayo Adhesive Probability (MAP) score (P < 0.001). The MAP score (P < 0.001) was the only variable that remained an independent predictor for APF in multivariate analysis. We found that patients with APF had longer operative times (P < 0.001), warm ischemia times (P = 0.001), and greater estimated blood loss (P = 0.003) than those without APF. However, there were no significant differences in surgical approach, transfusion rate, length of postoperative stay, complication rate, or surgical margin between the two groups. CONCLUSIONS: Several specific clinical and radiographic factors including the MAP score can predict APF. The presence of APF is associated with an increased operative time, warm ischemia time, and greater estimated blood loss but has no impact on other perioperative outcomes in LPN.

Amyand's hernia: a 10-year experience with 6 cases.

PURPOSE: Amyand's hernia is a rare hernia defined as an inguinal hernia that contains the appendix within the hernia sac. Current treatment of Amyand's hernia remains controversial. Our study retrospectively reviewed 6 cases of Amyand's hernia, aiming to provide a reference for the surgical treatment of Amyand's hernia. METHODS: Six patients diagnosed with Amyand's hernia from September 2010 to May 2020 were retrospectively enrolled in our study. We summarized clinical data of six patients including the chief complaint, physical examinations, laboratory examinations, imaging examinations, surgical methods, and postoperative treatments and outcomes. RESULTS: The diagnosis of six cases with Amyand's hernia was made during surgery. Two patients had normal appendixes whereas the remaining four patients had appendicitis. Two patients with normal appendix received tension-free mesh repair through the inguinal incision. Among those with inflamed or perforated appendixes, two received mesh repair and the other two did not. The discharge time after surgery of six patients was 9.8 ± 6.1 days. One patient suffered from a wound infection. No additional postoperative complications were detected. CONCLUSIONS: Computed tomography and ultrasonography are helpful but limited in the definite diagnosis of Amyand's hernia. The presence of a normal appendix does not require to be resected, but appendicectomy is necessary if the appendix is inflamed. The treatment of Amyand's hernia should be tailored based on the patient's condition and the type of Amyand's hernia.

Nanog mediates tobacco smoke-induced enhancement of renal cancer stem cell properties.

Nanog plays an important role in the regulation of cancer stem cells (CSCs) which participate in tumorgenesis and progression. In renal cancer, tobacco smoke (TS) is considered a major risk factor. However, the molecular mechanism by which TS induces the development of renal CSC properties remains largely unknown. In this study, we showed that the level of Nanog was elevated in renal cell carcinoma (RCC) patients with a smoking history, and that Nanog overexpression promoted the traits of CSCs in renal cancer. We further demonstrated that a 8-week exposure of TS enhanced the formation of renal tumorspheres, increased the population of CD133-positive cells, and stimulated the expression of Nanog and CSC markers. In addition, TS was found to play a role in accelerating the cell growth transition from G1 to S phase in renal CSCs. Finally, we demonstrated that the TS-induced effects in renal CSCs could be reversed through the downregulation of Nanog. Our results suggested that Nanog plays a role in mediating TS-induced renal CSC properties. This study may provide new insights into the molecular mechanism of TS-related renal tumorigenesis, which can contribute to the future development of therapeutics for renal cancer.

Generation of hepatobiliary organoids from human induced pluripotent stem cells.

BACKGROUND & AIMS: Human induced pluripotent stem cell (hiPSC)-derived liver modeling systems have the potential to overcome the shortage of donors for clinical application and become a model for drug development. Although several strategies are available to generate hepatic micro-tissues, few have succeeded in generating a liver organoid with hepatobiliary structure from hiPSCs. METHODS: At differentiation stages I and II (day 1-15), 25% of mTeSR™ culture medium was added to hepatic differentiation medium to induce endodermal and mesodermal commitment and thereafter hepatic and biliary co-differentiation. At stage III (day 15-45), 10% cholesterol+ MIX was added to the maturation medium to promote the formation and maturation of the hepatobiliary organoids. Phenotypes and functions of organoids were determined by specific markers and multiple functional assays both in vitro and in vivo. RESULTS: In this system, hiPSCs were induced to form 3D hepatobiliary organoids and to some extent recapitulated key aspects of early hepatogenesis in a parallel fashion. The organoids displayed a series of functional attributes. Specifically, the induced hepatocyte-like cells could take up indocyanine green, accumulate lipid and glycogen, and displayed appropriate secretion ability (albumin and urea) and drug metabolic ability (CYP3A4 activity and inducibility); the biliary structures in the system showed gamma glutamyltransferase activity and the ability to efflux rhodamine and store bile acids. Furthermore, after transplantation into the immune-deficient mice, the organoids survived for more than 8 weeks. CONCLUSION: This is the first time that functional hepatobiliary organoids have been generated from hiPSCs. The organoid model will be useful for in vitro studies of the molecular mechanisms of liver development and has important potential in the therapy of liver diseases. LAY SUMMARY: Herein, we established a system to generate human induced pluripotent stem cell-derived functional hepatobiliary organoids in vitro, without any exogenous cells or genetic manipulation. To some extent this model was able to recapitulate several key aspects of hepatobiliary organogenesis in a parallel fashion, holding great promise for drug development and liver transplantation.

Transcriptome analysis of larval immune defence in the lamprey Lethenteron japonicum.

The lamprey is a primitive jawless vertebrate that occupies a critical phylogenetic position, and its larval stage represents the major portion of its life cycle [1]. Lamprey larvae have been proven to be an important model organism for studying numerous biological problems, such as the immune system, due to their unique biological features [2]. In addition, early-stage larvae have never been obtained from the wild [3]; therefore, it is necessary to establish artificial breeding of lampreys in the laboratory. However, during early development, the larvae exhibit susceptibility to saprolegniasis, and the immune responses of lamprey larvae to this infection remain poorly understood. Here, we established a model of fungal infection in lamprey larvae and then used RNA sequencing to investigate the transcript profiles of lamprey larvae and their immune responses to Saprolegnia ferax. Among the profiled molecules, genes involved in pathogen recognition, inflammation, phagocytosis, lysosomal degradation, soluble humoral effectors, and lymphocyte development were significantly upregulated. The results were validated by analysis of several genes by quantitative real-time PCR and whole-mount in situ hybridization. Finally, we performed a Western blot for VLRs in infected and uninfected lampreys. This work not only provides an animal model for studying fungal infection but also suggests a molecular basis for developing defensive strategies to manage Saprolegnia ferax infection.

Disentangling the mechanisms behind winter snow impact on vegetation activity in northern ecosystems.

Although seasonal snow is recognized as an important component in the global climate system, the ability of snow to affect plant production remains an important unknown for assessing climate change impacts on vegetation dynamics at high-latitude ecosystems. Here, we compile data on satellite observation of vegetation greenness and spring onset date, satellite-based soil moisture, passive microwave snow water equivalent (SWE) and climate data to show that winter SWE can significantly influence vegetation greenness during the early growing season (the period between spring onset date and peak photosynthesis timing) over nearly one-fifth of the land surface in the region north of 30 degrees, but the magnitude and sign of correlation exhibits large spatial heterogeneity. We then apply an assembled path model to disentangle the two main processes (via changing early growing-season soil moisture, and via changing the growth period) in controlling the impact of winter SWE on vegetation greenness, and suggest that the "moisture" and "growth period" effect, to a larger extent, result in positive and negative snow-productivity associations, respectively. The magnitude and sign of snow-productivity association is then dependent upon the relative dominance of these two processes, with the "moisture" effect and positive association predominating in Central, western North America and Greater Himalaya, and the "growth period" effect and negative association in Central Europe. We also indicate that current state-of-the-art models in general reproduce satellite-based snow-productivity relationship in the region north of 30 degrees, and do a relatively better job of capturing the "moisture" effect than the "growth period" effect. Our results therefore work towards an improved understanding of winter snow impact on vegetation greenness in northern ecosystems, and provide a mechanistic basis for more realistic terrestrial carbon cycle models that consider the impacts of winter snow processes.

Metschnikowia persici sp. nov., A Novel Protease-Producing Yeast Species from China.

Three yeast strains, named as FHL-A, FHL-B, and FHL-C, were isolated from peach fruit surfaces collected from different regions in the North of China highly produced protease and were presented as single separate group in the genus Metschnikowia by sequence comparisons of 26S rRNA gene D1/D2 domain and internal transcribed spacer (ITS) region. BLASTn alignments on NCBI showed that the similarity of 26S rRNA gene sequences of the three strains to all sequences of other yeasts accessed into the GenBank/EMBL/DDBJ and other database was very low (≦93%). The phylogenetic tree based on the D1/D2 region of 26S rRNA gene sequences revealed that three strains are most closely related to Metschnikowia koreensis KCTC 7828T (AF257272.1) (sequence similarity: 93.0%) and Metschnikowia reukaufii CBS9709T (AJ716113.1) (sequence similarity: 93.0%). However, the strains are distinguished from M. koreensis by its non-assimilation of galactose, ribitol, and D-xylose, and by its growth at 37 °C or in vitamin-free medium, and are notably different from M. reukaufii by its non-assimilation of galactose, D-xylose, D-arabinose, and D-ribose, and by its growth at 35 °C or in vitamin-free medium. The strain FHL-B formed asci in V8 juice sporulation medium for 3 weeks. Therefore, the name Metschnikowia persici is proposed for the novel species, with FHL-B (= CBS12815T = CFCC 3578T) as the type strain.

Theoretical Analysis of the Dynamic Properties of a 2-2 Cement-Based Piezoelectric Dual-Layer Stacked Sensor under Impact Load.

Cement-based piezoelectric materials are widely used due to the fact that compared with common smart materials, they overcome the defects of structure-incompatibility and frequency inconsistency with a concrete structure. However, the present understanding of the mechanical behavior of cement-based piezoelectric smart materials under impact load is still limited. The dynamic characteristics under impact load are of importance, for example, for studying the anti-collision properties of engineering structures and aircraft takeoff-landing safety. Therefore, in this paper, an analytical model was proposed to investigate the dynamic properties of a 2-2 cement-based piezoelectric dual-layer stacked sensor under impact load based on the piezoelectric effect. Theoretical solutions are obtained by utilizing the variable separation and Duhamel integral method. To simulate the impact load and verify the theory, three types of loads, including atransient step load, isosceles triangle load and haversine wave load, are considered and the comparisons between the theoretical results, Li's results and numerical results are presented by using the control variate method and good agreement is found. Furthermore, the influences of several parameters were discussed and other conclusions about this sensor are also given. This should prove very helpful for the design and optimization of the 2-2 cement-based piezoelectric dual-layer stacked sensor in engineering.

Impact Mechanical Response of a 2-2 Cement-Based Piezoelectric Sensor Considering the Electrode Layer Effect.

Cement-based piezoelectric composite, has been widely used as a kind of smart material in structural health monitoring and active vibration control. However, transient dynamic loads such as impact loads may cause serious damage to the composite. Considering the electrode layer effect, this paper aimed to investigate the theoretical response of a 2-2 cement-based piezoelectric composite sensor subjected to an impact load. The vibration behaviors are analyzed by using the mode summation method and the virtual work principle. To simulate the impact load, transient haversine wave loads are assumed in the numerical simulation. Close agreements between theoretical and numerical solutions are found for peak transient haversine wave loads larger than 500 kPa, therefore proving the validity of the theory. Moreover, the influence of the electrode material and geometrical parameters on the dynamic characteristics of this sensor are considered. The present work should be beneficial to the design of this kind of sensor by taking into account the electrode layer effect.