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151.
Outstanding Low Temperature Thermoelectric Power Factor from Completely Organic Thin Films Enabled by Multidimensional Conjugated Nanomaterials 下载免费PDF全文
Chungyeon Cho Kevin L. Wallace Ping Tzeng Jui‐Hung Hsu Choongho Yu Jaime C. Grunlan 《Liver Transplantation》2016,6(7)
In an effort to create a paintable/printable thermoelectric material, comprised exclusively of organic components, polyaniline (PANi), graphene, and double‐walled nanotube (DWNT) are alternately deposited from aqueous solutions using the layer‐by‐layer assembly technique. Graphene and DWNT are stabilized with an intrinsically conductive polymer, poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). An 80 quadlayer thin film (≈1 μm thick), comprised of a PANi/graphene‐PEDOT:PSS/PANi/DWNT‐PEDOT:PSS repeating sequence, exhibits unprecedented electrical conductivity (σ ≈ 1.9 × 105 S m?1) and Seebeck coefficient (S ≈ 120 μV K?1) for a completely organic material. These two values yield a thermoelectric power factor (PF = S 2 σ ?1) of 2710 μW m?1 K?2, which is the highest value ever reported for a completely organic material and among the highest for any material measured at room temperature. These outstanding properties are attributed to the highly ordered structure in the multilayer assembly. This water‐based thermoelectric nanocomposite is competitive with the best inorganic semiconductors (e.g., bismuth telluride) at room temperature and can be applied as a coating to any flexible surface (e.g., fibers in clothing). For the first time, there is a real opportunity to harness waste heat from unconventional sources, such as body heat, to power devices in an environmentally‐friendly way. 相似文献
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154.
Mohammad Ali Amanda K. Debes Francisco J. Luquero Deok Ryun Kim Je Yeon Park Laura Digilio Byomkesh Manna Suman Kanungo Shanta Dutta Dipika Sur Sujit K. Bhattacharya David A. Sack 《PLoS medicine》2016,13(9)
IntroductionVaccinating a buffer of individuals around a case (ring vaccination) has the potential to target those who are at highest risk of infection, reducing the number of doses needed to control a disease. We explored the potential vaccine effectiveness (VE) of oral cholera vaccines (OCVs) for such a strategy.ConclusionsThese findings suggest that high-level protection can be achieved if individuals living close to cholera cases are living in a high coverage ring. Since this was an observational study including participants who had received two doses of vaccine (or placebo) in the clinical trial, further studies are needed to determine whether a ring vaccination strategy, in which vaccine is given quickly to those living close to a case, is feasible and effective.
Trial registration
ClinicalTrials.gov NCT00289224相似文献155.
Genetic evidence for prevalence of alloparental care in a socially monogamous biparental cichlid fish,Perissodus microlepis,from Lake Tanganyika supports the “selfish shepherd effect” hypothesis 下载免费PDF全文
Alloparental care – care for unrelated young – is rare in animals, and its ecological or evolutionary advantages or, alternative maladaptive nature, remain unclear. We investigate alloparental care in the socially monogamous cichlid fish Perissodus microlepis from Lake Tanganyika that exhibits bi‐parental care. In a genetic parentage analysis, we discovered a surprisingly high percentage of alloparental care represented by brood mixing, extra‐pair paternity and extra‐pair maternity in all broods that we investigated. The percentage of nondescendant juveniles of other parents, i.e., brood mixing, ranged from 5% to 57% (mean = 28%). The distribution of genetic parentage also suggests that this socially monogamous species has, in fact, polygamous mating system. The prevalence of genetically mixed broods can be best explained by two, not mutually exclusive hypotheses on farming‐out and fostering behaviors. In the majority of broods, the sizes of the parents’ own (descendant) offspring were significantly larger than those of the adopted (nondescendant) juveniles, supporting the ‘selfish shepherd effect’ hypothesis, i.e., that foster parents preferentially accept unrelated “smaller or not larger” young since this would tend to lower the predation risks for their own larger offspring. There was also a tendency for larger parents particularly mothers, more so than smaller parents, to care predominantly for their own offspring. Larger parents might be better at defending against cuckoldry and having foreign young dumped into their broods through farming‐out behavior. This result might argue for maladaptive effects of allopatric care for the foster parents that only larger and possibly more experienced pairs can guard against. It needs to be determined why, apparently, the ability to recognize one's own young has not evolved in this species. 相似文献
156.
Seoung Min Bong Kka-bi Son Seung-Won Yang Jae-Won Park Jea-Won Cho Kyung-Tae Kim Hackyoung Kim Seung Jun Kim Young Jun Kim Byung Il Lee 《PloS one》2016,11(3)
Myotubularin-related protein 1 (MTMR1) is a phosphatase that belongs to the tyrosine/dual-specificity phosphatase superfamily. MTMR1 has been shown to use phosphatidylinositol 3-monophosphate (PI(3)P) and/or phosphatidylinositol 3,5-bisphosphate (PI(3,5)P2) as substrates. Here, we determined the crystal structure of human MTMR1. The refined model consists of the Pleckstrin homology (PH)-GRAM and phosphatase (PTP) domains. The overall structure was highly similar to the previously reported MTMR2 structure. Interestingly, two phosphate molecules were coordinated by strictly conserved residues located in the C(X)5R motif of the active site. Additionally, our biochemical studies confirmed the substrate specificity of MTMR1 for PI(3)P and PI(3,5)P2 over other phosphatidylinositol phosphates. Our structural and enzymatic analyses provide insight into the catalytic mechanism and biochemical properties of MTMR1. 相似文献
157.
Yunji Hwang Kyu Eun Lee Elisabete Weiderpass Young Joo Park Young Jun Chai Hyungju Kwon Do Joon Park BeLong Cho Ho-Chun Choi Daehee Kang Sue K. Park 《PloS one》2016,11(3)
Background
This study evaluated the effects of acute high-dose and chronic lifetime exposure to alcohol and exposure patterns on the development of differentiated thyroid cancer (DTC).Methods
The Thyroid Cancer Longitudinal Study (T-CALOS) included 2,258 DTC patients (449 men and 1,809 women) and 22,580 healthy participants (4,490 men and 18,090 women) who were individually matched by age, gender, and enrollment year. In-person interviews were conducted with a structured questionnaire to obtain epidemiologic data. Clinicopathologic features of the patients were obtained by chart reviews. Odds ratios (ORs) and 95% confidence intervals (95%CI) were estimated using conditional regression models.Results
While light or moderate drinking behavior was related to a reduced risk of DTC, acute heavy alcohol consumption (151 g or more per event or on a single occasion) was associated with increased risks in men (OR = 2.22, 95%CI = 1.27–3.87) and women (OR = 3.61, 95%CI = 1.52–8.58) compared with never-drinkers. The consumption of alcohol for 31 or more years was a significant risk factor for DTC for both men (31–40 years: OR = 1.58, 95%CI = 1.10–2.28; 41+ years: OR = 3.46, 95%CI = 2.06–5.80) and women (31–40 years: OR = 2.18, 95%CI = 1.62–2.92; 41+ years: OR = 2.71, 95%CI = 1.36–5.05) compared with never-drinkers. The consumption of a large amount of alcohol on a single occasion was also a significant risk factor, even after restricting DTC outcomes to tumor size, lymph node metastasis, extrathyroidal extension and TNM stage.Conclusion
The findings of this study suggest that the threshold effects of acute high-dose alcohol consumption and long-term alcohol consumption are linked to an increased risk of DTC. 相似文献158.
Induction of MiR-21 by Stereotactic Body Radiotherapy Contributes to the Pulmonary Fibrotic Response
Ok-Seon Kwon Keun-Tae Kim Eunioo Lee Myoungjae Kim Seo-Hyun Choi Henghong Li Albert J. Fornace Jr. Jae-Ho Cho Yun-Sil Lee Ji-Seon Lee Yoon-Jin Lee Hyuk-Jin Cha 《PloS one》2016,11(5)
Radiation-induced lung fibrosis, the most serious effect of lung cancer radiotherapy on normal tissue, remains a major technical obstacle to the broader application of radiotherapy to patients with lung cancer. This study describes the use of an image-guided irradiation system in mice mimicking stereotactic body radiotherapy (SBRT) to examine the molecular features of chronic fibrotic response after radiation injury. MicroRNA (miR) array analysis of injured pulmonary tissue identified a set of miRs whose expression was significantly increased in damaged lung tissue. In particular, miR-21 expression was increased at the radiation injury site, concurrent with collagen deposition. Although the inhibition of miR-21 by its specific inhibitor anti-miR-21 only marginally affected endothelial-mesenchymal transition (EndMT) in lung endothelial cells, this inhibition significantly reduced collagen synthesis in lung fibroblasts. Furthermore, ectopic expression of miR-21 was sufficient to promote a fibrotic response in lung fibroblasts, enhancing Smad2 phosphorylation concurrent with Smad7 downregulation. These findings indicate that the induction of miR-21 expression is responsible for fibrotic responses observed in mesenchymal cells at the injury site through the potentiation of TGF-β signaling. Local targeting of miR-21 at the injured area could have potential therapeutic utility in mitigating radiation-induced lung fibrosis. 相似文献
159.
Donghyun Jee Seungbum Kang Changzheng Yuan Eunyoung Cho Jorge G. Arroyo The Epidemiologic Survey Committee of the Korean Ophthalmologic Society 《PloS one》2016,11(2)