Recent advances in the modelling of crack growth under fatigue loading conditions

Fatigue crack growth associated with cyclic (secondary) plastic flow near a crack front is modelled using an incremental formulation. A new description of threshold behaviour under small load cycles is included. Quasi-static crack extension under high load excursions is described using an incremental formulation of the R-(crack growth resistance)- curve concept. The integration of the equations is discussed. For constant amplitude load cycles the results will be compared with existing crack growth laws. It will be shown that the model also properly describes interaction effects of fatigue crack growth and quasi-static crack extension. To evaluate the more general applicability the model is included in the NASGRO computer code for damage tolerance analysis. For this purpose the NASGRO program was provided with the CORPUS and the STRIP-YIELD models for computation of the crack opening load levels. The implementation is discussed and recent results of the verification are presented

Final report for secure camera capture system (April 2016)

This report provides an overview of the Secure Camera Capture system produced by Team 6 in Spring 2016�s Senior Design 2 class. The project encompassed a three-part hardware and software system, used to capture, securely store, and retrieve photographs taken by an internet-equipped camera on a sixty-second timer. In the report, the project is outlined in both technical and nontechnical terms, the AES encryption method used, the Raspberry Pi microcontroller hardware, and the software used to tie them together. Specifications (both hardware and software) and how they were addressed are detailed, and a guide is provided to reconstruct the project using provided code. Finally, it provides the team�s perspective on the final product and possible improvements that could be made on the design

How Do Humans Control Physiological Strain during Strenuous Endurance Exercise?

Background: Methodology/principal Findings: Conclusions/significance: Distance running performance is a viable model of human locomotion.To evaluate the physiologic strain during competitions ranging from 5-100 km, we evaluated heart rate (HR) records of competitive runners (n = 211). We found evidence that: 1) physiologic strain (% of maximum HR (%HRmax)) increased in proportional manner relative to distance completed, and was regulated by variations in running pace; 2) the %HRmax achieved decreased with relative distance; 3) slower runners had similar %HRmax response within a racing distance compared to faster runners, and despite differences in pace, the profile of %HRmax during a race was very similar in runners of differing ability; and 4) in cases where there was a discontinuity in the running performance, there was evidence that physiologic effort was maintained for some time even after the pace had decreased.The overall results suggest that athletes are actively regulating their relative physiologic strain during competition, although there is evidence of poor regulation in the case of competitive failures.2.308 SJR (2008) Q1, 60/1774 Medicine (miscellaneous), 19/144 Biochemistry, genetics and molecular biology (miscellaneous), 15/175 Agricultural and biological sciences (miscellaneous)UE

Impaired Thymic Selection and Abnormal Antigen-Specific T Cell Responses in Foxn1Δ/Δ Mutant Mice

Foxn1(Δ/Δ) mutant mice have a specific defect in thymic development, characterized by a block in TEC differentiation at an intermediate progenitor stage, and blocks in thymocyte development at both the DN1 and DP cell stages, resulting in the production of abnormally functioning T cells that develop from an atypical progenitor population. In the current study, we tested the effects of these defects on thymic selection.We used Foxn1(Δ/Δ); DO11 Tg and Foxn1(Δ/Δ); OT1 Tg mice as positive selection and Foxn1(Δ/Δ); MHCII I-E mice as negative selection models. We also used an in vivo system of antigen-specific reactivity to test the function of peripheral T cells. Our data show that the capacity for positive and negative selection of both CD4 and CD8 SP thymocytes was reduced in Foxn1(Δ/Δ) mutants compared to Foxn1(+/Δ) control mice. These defects were associated with reduction of both MHC Class I and Class II expression, although the resulting peripheral T cells have a broad TCR Vβ repertoire. In this deficient thymic environment, immature CD4 and CD8 SP thymocytes emigrate from the thymus into the periphery. These T cells had an incompletely activated profile under stimulation of the TCR signal in vitro, and were either hypersensitive or hyporesponsive to antigen-specific stimulation in vivo. These cell-autonomous defects were compounded by the hypocellular peripheral environment caused by low thymic output.These data show that a primary defect in the thymic microenvironment can cause both direct defects in selection which can in turn cause indirect effects on the periphery, exacerbating functional defects in T cells

Cumulative live birth rates in low-prognosis women

No external funds were obtained for the present study. The OPTIMIST study was funded by The Netherlands Organization for Health Research and Development (ZonMW number 171102020).Peer reviewedPublisher PD

Population-Specific Responses to Interspecific Competition in the Gut Microbiota of Two Atlantic Salmon (Salmo salar) Populations

The gut microbial community in vertebrates plays a role in nutrient digestion and absorption, development of intestine and immune systems, resistance to infection, regulation of bone mass and even host behavior and can thus impact host fitness. Atlantic salmon (Salmo salar) reintroduction efforts into Lake Ontario, Canada, have been unsuccessful, likely due to competition with non-native salmonids. In this study, we explored interspecific competition effects on the gut microbiota of two Atlantic salmon populations (LaHave and Sebago) resulting from four non-native salmonids. After 10 months of rearing in semi-natural stream tanks under six interspecific competition treatments, we characterized the gut microbiota of 178 Atlantic salmon by parallel sequencing the 16S rRNA gene. We found 3978 bacterial OTUs across all samples. Microbiota alpha diversity and abundance of 27 OTUs significantly differed between the two populations. Interspecific competition reduced relative abundance of potential beneficial bacteria (six genera of lactic acid bacteria) as well as 13 OTUs, but only in the LaHave population, indicating population-specific competition effects. The pattern of gut microbiota response to interspecific competition may reflect local adaptation of the host-microbiota interactions and can be used to select candidate populations for improved species reintroduction success

RelB-Dependent Stromal Cells Promote T-Cell Leukemogenesis

BACKGROUND: The Rel/NF-kappaB transcription factors are often activated in solid or hematological malignancies. In most cases, NF-kappaB activation is found in malignant cells and results from activation of the canonical NF-kappaB pathway, leading to RelA and/or c-Rel activation. Recently, NF-kappaB activity in inflammatory cells infiltrating solid tumors has been shown to contribute to solid tumor initiation and progression. Noncanonical NF-kappaB activation, which leads to RelB activation, has also been reported in breast carcinoma, prostate cancer, and lymphoid leukemia. METHODOLOGY/PRINCIPAL FINDINGS: Here we report a novel role for RelB in stromal cells that promote T-cell leukemogenesis. RelB deficiency delayed leukemia onset in the TEL-JAK2 transgenic mouse model of human T acute lymphoblastic leukemia. Bone marrow chimeric mouse experiments showed that RelB is not required in the hematopoietic compartment. In contrast, RelB plays a role in radio-resistant stromal cells to accelerate leukemia onset and increase disease severity. CONCLUSIONS/SIGNIFICANCE: The present results are the first to uncover a role for RelB in the crosstalk between non-hematopoietic stromal cells and leukemic cells. Thus, besides its previously reported role intrinsic to specific cancer cells, the noncanonical NF-kappaB pathway may also play a pro-oncogenic role in cancer microenvironmental cells