445 research outputs found

    Experimental Study of Thin Film Sensor Networks for Wind Turbine Blade Damage Detection

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    Damage detection of wind turbine blades is difficult due to their complex geometry and large size, for which large deployment of sensing systems is typically not economical. A solution is to develop and deploy dedicated sensor networks fabricated from inexpensive materials and electronics. The authors have recently developed a novel skin-type strain gauge for measuring strain over very large surfaces. The skin, a type of large-area electronics, is constituted from a network of soft elastomeric capacitors. The sensing system is analogous to a biological skin, where local strain can be monitored over a global area. In this paper, we propose the utilization of a dense network of soft elastomeric capacitors to detect, localize, and quantify damage on wind turbine blades. We also leverage mature off the shelf technologies, in particular resistive strain gauges, to augment such dense sensor network with high accuracy data at key locations, therefore constituting a hybrid dense sensor network. The proposed hybrid dense sensor network is installed inside a wind turbine blade 1:25 scale model, and tested in a wind tunnel to simulate an operational environment. Results demonstrate the ability of the hybrid dense sensor network to detect, localize, and quantify damage

    Reward dysfunction in major depression: Multimodal neuroimaging evidence for refining the melancholic phenotype

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    Reward dysfunction is thought to play a core role in the pathophysiology of major depressive disorder (MDD). Event-related potential (ERP) and functional magnetic resonance imaging (fMRI) studies have identified reward processing deficits in MDD, but these methods have yet to be applied together in a single MDD sample. We utilized multimodal neuroimaging evidence to examine reward dysfunction in MDD. Further, we explored how neurobiological reward dysfunction would map onto subtypes of MDD. The feedback negativity (FN), an ERP index of reward evaluation, was recorded in 34 unmedicated depressed individuals and 42 never-depressed controls during a laboratory gambling task. Ventral striatal (VS) activation to reward was recorded in a separate fMRI session, using an identical task, among a subgroup of 24 depressed individuals and a comparison group of 18 non-depressed controls. FN amplitude was blunted in MDD. This effect was driven by a MDD subgroup characterized by impaired mood reactivity to positive events, a core feature of melancholic MDD. A similar pattern was observed for VS activation, which was also blunted among the MDD subgroup with impaired mood reactivity. Neither FN amplitude nor VS activation were related to the full, DSM-defined melancholic or atypical MDD subtypes. Across the MDD sample, FN amplitude and VS activation were correlated, indicating convergence across methods. These results indicate that not all MDD is characterized by reward dysfunction, and that there is meaningful heterogeneity in reward processing within MDD. The current study offers neurobiological evidence that impaired mood reactivity is a key phenotypic distinction for subtyping MDD, and further suggests that the existing melancholic phenotype may require further refinement

    Treatment of breast cancer: Imo State Nigeria versus Indiana, USA women -- comparative analytic study

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    BACKGROUND: Women with breast cancer undergo multimodal treatment for best outcome. This study seeks to identify the treatment challenges for such women in Imo State, Nigeria vis-à-vis similar women in Indiana USA. We compared the treatment modalities of both groups; noting predictors of compliance for subsequent action. SETTING: Federal Medical Centre, Owerri; Imo State, Imo State University, Orlu, Nigeria and Indiana University Hospital, Indiana, USA. DESIGN: A retrospective study. METHODOLOGY: From 2000-2013, 100 randomly pulled charts of patients treated for pathologically confirmed breast cancer in Imo, Nigeria Federal Medical Centre Owerri, Imo State University Hospital; and Indiana University Hospital U.S. respectively were reviewed. The demographics, clinical and pathological data of the patients with confirmed breast cancer were obtained. The data were formatted and analyzed with SPSS version 16.0. The clinical features, management options, outcomes and specific features were compared for both groups using Wilcoxon Rank Sum tests (age, parity) and chi-square tests for all other variables. A 5% significance level was used for all tests. RESULTS: One hundred patients were included for each group. The mean/minimum ages; Imo, Nigeria 41.7/21 (SD/SE 15.3/1.5) vs. Indiana, U.S.56.4/29 (SD 12.4/SE 1.2) p<0.0001. Histology for Indiana USA women was predominantly ductal carcinoma in situ (DCIS) P<0.0001 while that of Imo, Nigeria was invasive ductal carcinoma inflammatory cancer P<0.0326. Women in both locations received chemotherapy and surgery. Imo women received less radiotherapy. Toxicity from chemotherapy remained constant features for both groups, P<0.0001. In Indiana USA, the 5year survival exceeded 85%; In Imo Nigeria it was 10%. This study showed that Women on both locations who were likely to be compliant were those receiving mastectomy; Imo, Nigeria 44(56%) <0.013 vs. Indiana, U.S. 74(80%) p<0.0186; women with cosmesis given; Imo, Nigeria 41(42%) vs. Indiana, U.S. 91 (94%) p<0.0001. Sample sizes were inadequate to perform multivariable models. CONCLUSION: The multimodal treatment regimen implied that there was need for an algorithm protocol for breast cancer women. Thus the need to improve the quality of treatment particularly in Nigeria by improved treatment documentation to overcome key barriers involving information exchange

    Grassy–herbaceous land moderates regional climate effects on honey bee colonies in the Northcentral US

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    The lack of seasonally sustained floral resources (i.e. pollen and nectar) is considered a primary global threat to pollinator health. However, the ability to predict the abundance of flowering resources for pollinators based upon climate, weather, and land cover is difficult due to insufficient monitoring over adequate spatial and temporal scales. Here we use spatiotemporally distributed honey bee hive scales that continuously measure hive weights as a standardized method to assess nectar intake. We analyze late summer colony weight gain as the response variable in a random forest regression model to determine the importance of climate, weather, and land cover on honey bee colony productivity. Our random forest model predicted resource acquisition by honey bee colonies with 71% accuracy, highlighting the detrimental effects of warm, wet regions in the Northcentral United States on nectar intake, as well as the detrimental effect of years with high growing degree day accumulation. Our model also predicted that grassy–herbaceous natural land had a positive effect on the summer nectar flow and that large areas of natural grassy–herbaceous land around apiaries can moderate the detrimental effects of warm, wet climates. These patterns characterize multi-scale ecological processes that constrain the quantity and quality of pollinator nutritional resources. That is, broad climate conditions constrain regional floral communities, while land use and weather act to further modify the quantity and quality of pollinator nutritional resources. Observing such broad-scale trends demonstrates the potential for utilizing hive scales to monitor the effects of climate change on landscape-level floral resources for pollinators. The interaction of climate and land use also present an opportunity to manage for climate-resilient landscapes that support pollinators through abundant floral resources under climate change

    Imiquimod Does not Affect Shedding of Viable Chlamydiae in a Murine Model of Chlamydia trachomatis Genital Tract Infection

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    Objective: We postulated that either oral or vaginal administration of the immune response modifier imiquimod would decrease vaginal shedding of Chlamydia trachomatis, mouse pneumonitis strain (MoPn), in a murine model. Methods: Female BALB/c mice were infected intravaginally withC. trachomatis (MoPn) and were administered imiquimod either orally (30 mg/kg) or vaginally (10 μl of 5%imiquimod cream) prior to infection and every second day after infection for a total of four doses. The course of infection was monitored by collecting cervical–vaginal swabs and isolation in HeLa 229 cell culture. To determine whether the drug affected T helper type 1 or T helper type 2 immune response polarization, immunoglobulinG(IgG) subclass antibody responses were assessed at day 56 after infection. Results: There was no significant difference in the course of infection when imiquimod-treated mice were compared with sham-treated controls, regardless of whether the drug was administered orally or vaginally. IgG subclass antibody responses, and by extension, T helper type 1 to T helper type 2 immune response polarization, were also unaffected. Conclusions: Imiquimod has no efficacy in controllingC. trachomatis (MoPn) infection in the murine model

    Plasma 24S-hydroxycholesterol levels in elderly subjects with late onset Alzheimer's disease or vascular dementia: a case-control study

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    <p>Abstract</p> <p>Background</p> <p>In central nervous system cholesterol cannot be degraded but is secreted into circulation predominantly in the form of its polar metabolite 24(<it>S</it>)-hydroxycholesterol (24S-OH-Chol). Some studies suggested an association between 24S-OH-Chol metabolism and different neurological diseases including dementia. A possible decrease in 24S-OH-Chol plasma levels has been reported late onset Alzheimer's disease (LOAD) and vascular dementia (VD), but results of previous studies are partially contradictory.</p> <p>Methods</p> <p>By high-speed liquid chromatography/tandem mass spectrometry we evaluated the plasma levels of 24S-OH-Chol in a sample of 160 older individuals: 60 patients with LOAD, 35 patients with VD, 25 subjects affected by cognitive impairment no-dementia (CIND), and 40 (144 for genetics study) cognitively normal Controls. We also investigated the possible association between PPARgamma Pro12Ala polymorphism and dementia or 24S-OH-Chol levels.</p> <p>Results</p> <p>Compared with Controls, plasma 24S-OH-Chol levels were higher in LOAD and lower in VD; a slight not-significant increase in CIND was observed (ANOVA p: 0.001). A positive correlation between 24S-OH-Chol/TC ratio and plasma C reactive protein (CRP) levels was found in the whole sample, independent of possible confounders (multiple regression p: 0.04; r<sup>2</sup>: 0.10). This correlation was strong in LOAD (r: 0.39), still present in CIND (r: 0.20), but was absent in VD patients (r: 0.08). The PPARgamma Pro12Ala polymorphism was not associated with the diagnosis of LOAD, VD, or CIND; no correlation emerged between the Ala allele and 24S-OH-Chol plasma levels.</p> <p>Conclusions</p> <p>Our results suggest that plasma 24S-OH-Chol levels might be increased in the first stages of LOAD, and this phenomenon might be related with systemic inflammation. The finding of lower 24S-OH-Chol concentrations in VD might be related with a more advanced stage of VD compared with LOAD in our sample, and/or to different pathogenetic mechanisms and evolution of these two forms of dementia.</p

    Using Structure to Explore the Sequence Alignment Space of Remote Homologs

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    Protein structure modeling by homology requires an accurate sequence alignment between the query protein and its structural template. However, sequence alignment methods based on dynamic programming (DP) are typically unable to generate accurate alignments for remote sequence homologs, thus limiting the applicability of modeling methods. A central problem is that the alignment that is “optimal” in terms of the DP score does not necessarily correspond to the alignment that produces the most accurate structural model. That is, the correct alignment based on structural superposition will generally have a lower score than the optimal alignment obtained from sequence. Variations of the DP algorithm have been developed that generate alternative alignments that are “suboptimal” in terms of the DP score, but these still encounter difficulties in detecting the correct structural alignment. We present here a new alternative sequence alignment method that relies heavily on the structure of the template. By initially aligning the query sequence to individual fragments in secondary structure elements and combining high-scoring fragments that pass basic tests for “modelability”, we can generate accurate alignments within a small ensemble. Our results suggest that the set of sequences that can currently be modeled by homology can be greatly extended

    SDHA gain-of-function engages inflammatory mitochondrial retrograde signaling via KEAP1-Nrf2.

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    Whether screening the metabolic activity of immune cells facilitates discovery of molecular pathology remains unknown. Here we prospectively screened the extracellular acidification rate as a measure of glycolysis and the oxygen consumption rate as a measure of mitochondrial respiration in B cells from patients with primary antibody deficiency. The highest oxygen consumption rate values were detected in three study participants with persistent polyclonal B cell lymphocytosis (PPBL). Exome sequencing identified germline mutations in SDHA, which encodes succinate dehydrogenase subunit A, in all three patients with PPBL. SDHA gain-of-function led to an accumulation of fumarate in PPBL B cells, which engaged the KEAP1-Nrf2 system to drive the transcription of genes encoding inflammatory cytokines. In a single patient trial, blocking the activity of the cytokine interleukin-6 in vivo prevented systemic inflammation and ameliorated clinical disease. Overall, our study has identified pathological mitochondrial retrograde signaling as a disease modifier in primary antibody deficiency
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