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Rethinking how external pressure can suppress dendrites in lithium metal batteries
We offer an explanation for how dendrite growth can be inhibited when Li metal pouch cells are subjected to external loads, even for cells using soft, thin separators. We develop a contact mechanics model for tracking Li surface and sub-surface stresses where electrodes have realistically (micron-scale) rough surfaces. Existing models examine a single, micron-scale Li metal protrusion under a fixed local current density that presses more or less conformally against a separator or stiff electrolyte. At the larger, sub-mm scales studied here, contact between the Li metal and the separator is heterogeneous and far from conformal for surfaces with realistic roughness: the load is carried at just the tallest asperities, where stresses reach tens of MPa, while most of the Li surface feels no force at all. Yet, dendrite growth is suppressed over the entire Li surface. To explain this dendrite suppression, our electrochemical/mechanics model suggests that Li avoids plating at the tips of growing Li dendrites if there is sufficient local stress; that local contact stresses there may be high enough to close separator pores so that incremental Li+ ions plate elsewhere; and that creep ensures that Li protrusions are gradually flattened. These mechanisms cannot be captured by single-dendrite-scale analyses
Association of Exposure to Phthalates with Endometriosis and Uterine Leiomyomata: Findings from NHANES, 1999-2004
BACKGROUND. Phthalates are ubiquitous chemicals used in consumer products. Some phthalates are reproductive toxicants in experimental animals, but human data are limited. OBJECTIVE. We conducted a cross-sectional study of urinary phthalate metabolite concentrations in relation to self-reported history of endometriosis and uterine leiomyomata among 1,227 women 20-54 years of age from three cycles of the National Health and Nutrition Examination Survey (NHANES), 1999-2004. METHODS. We examined four phthalate metabolites: mono(2-ethylhexyl) phthalate (MEHP), monobutyl phthalate (MBP), monoethyl phthalate (MEP), and monobenzyl phthalate (MBzP). From the last two NHANES cycles, we also examined mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono(2-ethyl-5-oxohexyl) phthalate (MEOHP). We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for potential confounders. RESULTS. Eighty-seven (7%) and 151 (12%) women reported diagnoses of endometriosis and leiomyomata, respectively. The ORs comparing the highest versus lowest three quartiles of urinary MBP were 1.36 (95% CI, 0.77-2.41) for endometriosis, 1.56 (95% CI, 0.93-2.61) for leiomyomata, and 1.71 (95% CI, 1.07-2.75) for both conditions combined. The corresponding ORs for MEHP were 0.44 (95% CI, 0.19-1.02) for endometriosis, 0.63 (95% CI, 0.35-1.12) for leiomyomata, and 0.59 (95% CI, 0.37-0.95) for both conditions combined. Findings for MEHHP and MEOHP agreed with findings for MEHP with respect to endometriosis only. We observed null associations for MEP and MBzP. Associations were similar when we excluded women diagnosed > 7 years before their NHANES evaluation. CONCLUSION. The positive associations for MBP and inverse associations for MEHP in relation to endometriosis and leiomyomata warrant investigation in prospective studies
Vitamin D supplementation and breast cancer prevention : a systematic review and meta-analysis of randomized clinical trials
In recent years, the scientific evidence linking vitamin D status or supplementation to breast cancer has grown notably. To investigate the role of vitamin D supplementation on breast cancer incidence, we conducted a systematic review and meta-analysis of randomized controlled trials comparing vitamin D with placebo or no treatment. We used OVID to search MEDLINE (R), EMBASE and CENTRAL until April 2012. We screened the reference lists of included studies and used the βRelated Articleβ feature in PubMed to identify additional articles. No language restrictions were applied. Two reviewers independently extracted data on methodological quality, participants, intervention, comparison and outcomes. Risk Ratios and 95% Confident Intervals for breast cancer were pooled using a random-effects model. Heterogeneity was assessed using the I2 test. In sensitivity analysis, we assessed the impact of vitamin D dosage and mode of administration on treatment effects. Only two randomized controlled trials fulfilled the pre-set inclusion criteria. The pooled analysis included 5372 postmenopausal women. Overall, Risk Ratios and 95% Confident Intervals were 1.11 and 0.74β1.68. We found no evidence of heterogeneity. Neither vitamin D dosage nor mode of administration significantly affected breast cancer risk. However, treatment efficacy was somewhat greater when vitamin D was administered at the highest dosage and in combination with calcium (Risk Ratio 0.58, 95% Confident Interval 0.23β1.47 and Risk Ratio 0.93, 95% Confident Interval 0.54β1.60, respectively). In conclusions, vitamin D use seems not to be associated with a reduced risk of breast cancer development in postmenopausal women. However, the available evidence is still limited and inadequate to draw firm conclusions. Study protocol code: FARM8L2B5L
T-regulatory cell modulation: the future of cancer immunotherapy?
T-regulatory cells suppress anti-tumour immunity in cancer patients and in murine tumour models. Furthermore, their activity is likely to have an effect on the effectiveness of immunotherapeutic treatments for cancer. Here we describe the current status of developing clinical strategies for modulating Treg activity in cancer patients
Toll-Like Receptor (TLR) and Nucleosome-binding Oligomerization Domain (NOD) gene polymorphisms and endometrial cancer risk
Background: Endometrial cancer is the most common gynaecological malignancy in women of developed countries. Many risk factors implicated in endometrial cancer trigger inflammatory events; therefore, alterations in immune response may predispose an individual to disease. Toll-like receptors (TLRs) and nucleosome-binding oligomerization domain (NOD) genes are integral to the recognition of pathogens and are highly polymorphic. For these reasons, the aim of the study was to assess the frequency of polymorphic variants in TLR and NOD genes in an Australian endometrial cancer population. Methods: Ten polymorphisms were genotyped in 191 endometrial cancer cases and 291 controls using real-time PCR: NOD1 (rs2075822, rs2907749, rs2907748), NOD2 (rs5743260, rs2066844, rs2066845), TLR2 (rs5743708), TLR4 (rs4986790) and TLR9 (rs5743836, rs187084). Results: Haplotype analysis revealed that the combination of the variant alleles of the two TLR9 polymorphisms, rs5743836 and rs187084, were protective for endometrial cancer risk: OR 0.11, 95% CI (0.03-0.44), p = 0.002. This result remained highly significant after adjustment for endometrial cancer risk factors and Bonferroni correction for multiple testing. There were no other associations observed for the other polymorphisms in TLR2, TLR4, NOD1 and NOD2. Conclusions: The variant 'C' allele of rs5743836 causes greater TLR9 transcriptional activity compared to the 'T' allele, therefore, higher TLR9 activity may be related to efficient removal of microbial pathogens within the endometrium. Clearly, the association of these TLR9 polymorphisms and endometrial cancer risk must be further examined in an independent population. The results point toward the importance of examining immune response in endometrial tumourgenesis to understand new pathways that may be implicated in disease
The influence of the Cyclin D1 870 G>A polymorphism as an endometrial cancer risk factor
<p>Abstract</p> <p>Background</p> <p>Cyclin D1 is integral for the G1 to S phase of the cell cycle as it regulates cellular proliferation. A polymorphism in cyclin D1, 870 G>A, causes overexpression and supports uncontrollable cellular growth. This polymorphism has been associated with an increased risk of developing many cancers, including endometrial cancer.</p> <p>Methods</p> <p>The 870 G>A polymorphisms (rs605965) in the cyclin D1 gene was genotyped in an Australian endometrial cancer case-control population including 191 cases and 291 controls using real-time PCR analysis. Genotype analysis was performed using chi-squared (Ο<sup>2</sup>) statistics and odds ratios were calculated using unconditional logistic regression, adjusting for potential endometrial cancer risk factors.</p> <p>Results</p> <p>Women homozygous for the variant cyclin D1 870 AA genotype showed a trend for an increased risk of developing endometrial cancer compared to those with the wild-type GG genotype, however this result was not statistically significant (OR 1.692 95% CI (0.939β3.049), p = 0.080). Moreover, the 870 G>A polymorphism was significantly associated with family history of colorectal cancer. Endometrial cancer patients with the homozygous variant AA genotype had a higher frequency of family members with colorectal cancer in comparison to endometrial cancer patients with the GG and combination of GG and GA genotypes (GG versus AA; OR 2.951, 95% CI (1.026β8.491), p = 0.045, and GG+GA versus AA; OR 2.265, 95% CI (1.048β4.894), p = 0.038, respectively).</p> <p>Conclusion</p> <p>These results suggest that the cyclin D1 870 G>A polymorphism is possibly involved in the development of endometrial cancer. A more complex relationship was observed between this polymorphism and familial colorectal cancer.</p
The Role of Individual Variables, Organizational Variables and Moral Intensity Dimensions in Libyan Management Accountantsβ Ethical Decision Making
This study investigates the association of a broad set of variables with the ethical decision making of management accountants in Libya. Adopting a cross-sectional methodology, a questionnaire including four different ethical scenarios was used to gather data from 229 participants. For each scenario, ethical decision making was examined in terms of the recognition, judgment and intention stages of Restβs model. A significant relationship was found between ethical recognition and ethical judgment and also between ethical judgment and ethical intention, but ethical recognition did not significantly predict ethical intentionβthus providing support for Restβs model. Organizational variables, age and educational level yielded few significant results. The lack of significance for codes of ethics might reflect their relative lack of development in Libya, in which case Libyan companies should pay attention to their content and how they are supported, especially in the light of the under-development of the accounting profession in Libya. Few significant results were also found for gender, but where they were found, males showed more ethical characteristics than females. This unusual result reinforces the dangers of gender stereotyping in business. Personal moral philosophy and moral intensity dimensions were generally found to be significant predictors of the three stages of ethical decision making studied. One implication of this is to give more attention to ethics in accounting education, making the connections between accounting practice and (in Libya) Islam. Overall, this study not only adds to the available empirical evidence on factors affecting ethical decision making, notably examining three stages of Restβs model, but also offers rare insights into the ethical views of practising management accountants and provides a benchmark for future studies of ethical decision making in Muslim majority countries and other parts of the developing world
Reactive power and voltage control in grid-connected wind farms: an online optimization based fast model predictive control approach
What are the benefits of cognitive enhancers for Alzheimer's Disease: use of Population Impact Measures
A Pilot Study of IL-2RΞ± Blockade during Lymphopenia Depletes Regulatory T-cells and Correlates with Enhanced Immunity in Patients with Glioblastoma
Preclinical studies in mice have demonstrated that the prophylactic depletion of immunosuppressive regulatory T-cells (T(Regs)) through targeting the high affinity interleukin-2 (IL-2) receptor (IL-2RΞ±/CD25) can enhance anti-tumor immunotherapy. However, therapeutic approaches are complicated by the inadvertent inhibition of IL-2RΞ± expressing anti-tumor effector T-cells.To determine if changes in the cytokine milieu during lymphopenia may engender differential signaling requirements that would enable unarmed anti-IL-2RΞ± monoclonal antibody (MAbs) to selectively deplete T(Regs) while permitting vaccine-stimulated immune responses.A randomized placebo-controlled pilot study was undertaken to examine the ability of the anti-IL-2RΞ± MAb daclizumab, given at the time of epidermal growth factor receptor variant III (EGFRvIII) targeted peptide vaccination, to safely and selectively deplete T(Regs) in patients with glioblastoma (GBM) treated with lymphodepleting temozolomide (TMZ).Daclizumab treatment (n = 3) was well-tolerated with no symptoms of autoimmune toxicity and resulted in a significant reduction in the frequency of circulating CD4+Foxp3+ TRegs in comparison to saline controls (n = 3)( p = 0.0464). A significant (p<0.0001) inverse correlation between the frequency of TRegs and the level of EGFRvIII specific humoral responses suggests the depletion of TRegs may be linked to increased vaccine-stimulated humoral immunity. These data suggest this approach deserves further study.ClinicalTrials.gov NCT00626015
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