Effect of structural relaxation on the electronic structure of graphene on hexagonal boron nitride

We performed calculations of electronic, optical and transport properties of graphene on hBN with realistic moir\'e patterns. The latter are produced by structural relaxation using a fully atomistic model. This relaxation turns out to be crucially important for electronic properties. We describe experimentally observed features such as additional Dirac points and the "Hofstadter butterfly" structure of energy levels in a magnetic field. We find that the electronic structure is sensitive to many-body renormalization of the local energy gap.Comment: 5 pages, 6 figures. Supplementary material is available at http://www.theorphys.science.ru.nl/people/yuan/attachments/sm_hbn.pd

Effect of structural relaxation on the electronic structure of graphene on hexagonal boron nitride

We performed calculations of electronic, optical and transport properties of graphene on hBN with realistic moir\'e patterns. The latter are produced by structural relaxation using a fully atomistic model. This relaxation turns out to be crucially important for electronic properties. We describe experimentally observed features such as additional Dirac points and the "Hofstadter butterfly" structure of energy levels in a magnetic field. We find that the electronic structure is sensitive to many-body renormalization of the local energy gap.Comment: 5 pages, 6 figures. Supplementary material is available at http://www.theorphys.science.ru.nl/people/yuan/attachments/sm_hbn.pd

Genome-Wide Divergence in the West-African Malaria Vector Anopheles melas

Anopheles melas is a member of the recently diverged An. gambiae species complex, a model for speciation studies, and is a locally important malaria vector along the West-African coast where it breeds in brackish water. A recent population genetic study of An. melas revealed species-level genetic differentiation between three population clusters. An. melas West extends from The Gambia to the village of Tiko, Cameroon. The other mainland cluster, An. melas South, extends from the southern Cameroonian village of Ipono to Angola. Bioko Island, Equatorial Guinea An. melas populations are genetically isolated from mainland populations. To examine how genetic differentiation between these An. melas forms is distributed across their genomes, we conducted a genome-wide analysis of genetic differentiation and selection using whole genome sequencing data of pooled individuals (Pool-seq) from a representative population of each cluster. The An. melas forms exhibit high levels of genetic differentiation throughout their genomes, including the presence of numerous fixed differences between clusters. Although the level of divergence between the clusters is on a par with that of other species within the An. gambiae complex, patterns of genome-wide divergence and diversity do not provide evidence for the presence of pre- and/or postmating isolating mechanisms in the form of speciation islands. These results are consistent with an allopatric divergence process with little or no introgression

Three-color dSTORM Imaging and Analysis of Recombination Foci in Mouse Spread Meiotic Nuclei

During the first meiotic prophase in mouse, repair of SPO11-induced DNA double-strand breaks (DSBs), facilitating homologous chromosome synapsis, is essential to successfully complete the first meiotic cell division. Recombinases RAD51 and DMC1 play an important role in homology search, but their mechanistic contribution to this process is not fully understood. Super-resolution, single-molecule imaging of RAD51 and DMC1 provides detailed information on recombinase accumulation on DSBs during meiotic prophase. Here, we present a detailed protocol of recombination foci analysis of three-color direct stochastic optical reconstruction microscopy (dSTORM) imaging of SYCP3, RAD51, and DMC1, fluorescently labeled by antibody staining in mouse spermatocytes. This protocol consists of sample preparation, data acquisition, pre-processing, and data analysis. The sample preparation procedure includes an updated version of the nuclear spreading of mouse testicular cells, followed by immunocytochemistry and the preparation steps for dSTORM imaging. Data acquisition consists of three-color dSTORM imaging, which is extensively described. The pre-processing that converts fluorescent signals to localization data also includes channel alignment and image reconstruction, after which regions of interest (ROIs) are identified based on RAD51 and/or DMC1 localization patterns. The data analysis steps then require processing of the fluorescent signal localization within these ROIs into discrete nanofoci, which can be further analyzed. This multistep approach enables the systematic investigation of spatial distributions of proteins associated with individual DSB sites and can be easily adapted for analyses of other foci-forming proteins. All computational scripts and software are freely accessible, making them available to a broad audience.</p

Health-related quality of life of long-term high-grade glioma survivors

The objective of this study was to compare the health-related quality of life (HRQOL) of long-term to short-term high-grade glioma (HGG) survivors, determine the prognostic value of HRQOL for overall survival, and determine the effect of tumor recurrence on HRQOL for long-term survivors. Following baseline assessment (after surgery, before radiotherapy), self-perceived HRQOL (using the Medical Outcomes Study Short Form 36 [SF-36]) and brain tumor-specific symptoms (using the 20-item Brain Cancer Module) were assessed every 4 months until 16 months after histological diagnosis. Kaplan-Meier survival analysis and the Cox proportional hazards model were performed to estimate overall survival of patients with impaired scores on the aggregated SF-36 higher-order summary scores measuring physical functioning on a physical component scale and on a mental component scale (MCS). Sixteen patients with a short-term survival (baseline and 4-month follow-up) and 16 with a long-term survival (follow-up until 16 months after diagnosis) were selected out of 68 initially recruited HGG patients. At baseline, the short-term and long-term survivors did not differ in their HRQOL. Between baseline and the 4-month follow-up, HRQOL of short-term survivors deteriorated, whereas the long-term survivors improved to a level comparable to healthy controls. Patients with impaired mental functioning (MCS) at baseline had a shorter median survival than patients with normal functioning. After accounting for differences in patient and tumor characteristics, however, mental functioning was not independently related to poorer overall survival. Not surprisingly, in the group of long-term survivors, the five patients with recurrence had a more compromised HRQOL at the 16-month follow-up compared to the 11 patients without recurrence. We concluded that baseline HRQOL is not related to duration of survival and that long-term survivors show improvement of HRQOL to a level comparable to that of the healthy

Risk factors for pelvic girdle pain postpartum and pregnancy related low back pain postpartum:a systematic review and meta-analysis

Contains fulltext : 221001.pdf (Publisher’s version ) (Closed access)BACKGROUND: Although pelvic girdle pain postpartum and pregnancy related low back pain postpartum (combined and named PGPP in this study) have a natural favourable course, there is a subgroup of women who have persistent complaints. The objective of this study was to identify personal-, (pre)pregnancy-, obstetric-, and child related risk factors on PGPP by means of a systematic literature review and meta-analysis. METHODS: Literature searches of PubMed, EMBASE, CINAHL and Cochrane up to October 2018 were conducted. Prospective cohort studies in English or Dutch describing three or more risk factors for PGPP were included. We assessed articles for inclusion and risk of bias. Studies with high risk of bias were excluded from data extraction. Data was extracted and checked for accuracy confirming to the CHARMS-checklist. Homogeneous variables were pooled. RESULTS: Twelve full text studies were assessed. Seven studies were excluded due to high risk of bias. Data was extracted from five studies. Multivariate analysis was not possible due to heterogeneity in included risk factors as well as outcome measures on risk factor per study. Pooled univariate significant risk factors on PGPP were: a history of low back pain, pre-pregnancy body mass index >25, pelvic girdle pain in pregnancy, depression in pregnancy, and a heavy workload in pregnancy. No significant obstetric and child related risk factors were reported. CONCLUSIONS: Risk factors on PGPP have been identified. Since multivariate analysis was not possible the outcome should be treated with care, because interaction between risk factors could not be analysed

Comparison of soybean Cultivars enriching Cd and the application foreground of the low-accumulating Cultivar in production

Contaminated soil collected from an agricultural field was used to compare Cd enrichment among 20 soybean cultivars to explore their application foregrounds in safe production. The results showed that Cd concentration in beans of 20 soybean cultivars was from 0.23 mg kg-1 to 2.33 mg kg-1 when Cd concentration in soil was 1.98 mg kg-1. Cd enrichment factors of 19 cultivars were lower than 1. Cd translocation factors of all cultivars were lower than 1. As for background soil with 0.15 mg kg-1 Cd, the concentrations of Cd in beans of two soybean cultivars were higher than 0.10 mg kg-1 (an agricultural trade standard of non-pollution food for soybean of China, NY5310-2005). Thus, the use of a low-accumulation soybean cultivar in Cd-contaminated soil should be done carefully and with reserve. Keywords: Cd, soybean cultivar, enrichment factor, phytoremediation, safe productio

Monitoring Response to Radiotherapy in Human Squamous Cell Cancer Bearing Nude Mice: Comparison of 2′-deoxy-2′-[18F]fluoro-d-glucose (FDG) and 3′-[18F]fluoro-3′-deoxythymidine (FLT)

Objective: The uptake of 3′-[18F]fluoro-3′- deoxythymidine (FLT), a proliferation marker, was measured before and during fractionated radiotherapy to evaluate the potential of FLT-positron emission tomography (PET) imaging as an indicator of tumor response compared to 2′-deoxy-2′-[18F]fluoro-d-glucose (FDG). Materials and Methods: Nude mice bearing established human head and neck xenografts (HNX-OE; nu/nu mice) were locally irradiated (three fractions/week; 22 Gy) using a 150-kVp unit. Multiple FDG- and FLT-PET scans were acquired during treatment. Tumor volume was determined regularly, and tissue was analyzed for biomarkers involved in tracer uptake. Results: Both groups revealed a significant decline in tumor volume (P∈<∈0.01) compared to untreated tumors. For FDG as well as for FLT, a significant decline in retention was observed at day 4. For FLT, most significant decline in retention was observed at day 12; whereas, for FDG, this was already noted at day 4. Maximum decline in tumor-to-nontumor ratios (T/NT) for FDG and FLT was 42∈±∈18% and 49∈±∈16% (mean∈± ∈SD), respectively. FLT uptake was higher then that of FDG. For FLT, statistical significant correlations were found for both tumor volume at baseline and at day 29 with T/NT and ΔT/NT. All tumors demonstrated expression of glucose transporter-1, thymidine kinase-1, and hexokinase II. No differences were found for amount of tumor cells and necrosis at the end of treatment. Conclusion: This new experimental in vivo model supports the promise of using FLT-PET, as with FDG-PET, to monitor response to external radiotherapy. This warrants further clinical studies to compare these two tracers especially in cancers treated with radiotherapy