Miracle-dz/UniFAR-FTUs huggingface dataset:
Buckling failures in insect exoskeletons

Thin walled tubes are often used for load-bearing structures, in nature and in engineering, because they offer good resistance to bending and torsion at relatively low weight. However, when loaded in bending they are prone to failure by buckling. It is difficult to predict the loading conditions which cause buckling, especially for tubes whose cross sections are not simple shapes. Insights into buckling prevention might be gained by studying this phenomenon in the exoskeletons of insects and other arthropods. We investigated the leg segments (tibiae) of five different insects: the locust (Schistocerca gergaria), American cockroach (Periplaneta americana), death’s head cockroach (Blaberus discoidalis), stick insect (Parapachymorpha zomproi) and bumblebee (Bombus terrestris audax). These were tested to failure in cantilever bending and modelled using finite element analysis (FEA). The tibiae of the locust and the cockroaches were found to be approximately circular in shape. Their buckling loads were well predicted by linear elastic FEA, and also by one of the analytical solutions available in the literature for elastic buckling. The legs of the stick insect are also circular in cross section but have several prominent longitudinal ridges. We hypothesised that these ridges might protect the legs against buckling but we found that this was not the case: the loads necessary for elastic buckling were not reached in practice because yield occurred in the material, causing plastic buckling. The legs of bees have a non-circular cross section due to a pollen-carrying feature (the corbicula). We found that this did not significantly affect their resistance to buckling. Our results imply that buckling is the dominant failure mode in the tibia of insects; it likely to be a significant consideration for other arthropods and any organisms with stiff exoskeletons. The interactions displayed here between material properties and cross sectional geometry may provide insights for the biomimetic design of engineering structures using thin walled tubes.
Neurocognitive Systems Related to Real-World Prospective Memory

Background Prospective memory (PM) denotes the ability to remember to perform actions in the future. It has been argued that standard laboratory paradigms fail to capture core aspects of PM. Methodology/Principal Findings We combined functional MRI, virtual reality, eye-tracking and verbal reports to explore the dynamic allocation of neurocognitive processes during a naturalistic PM task where individuals performed errands in a realistic model of their residential town. Based on eye movement data and verbal reports, we modeled PM as an iterative loop of five sustained and transient phases: intention maintenance before target detection (TD), TD, intention maintenance after TD, action, and switching, the latter representing the activation of a new intention in mind. The fMRI analyses revealed continuous engagement of a top-down fronto-parietal network throughout the entire task, likely subserving goal maintenance in mind. In addition, a shift was observed from a perceptual (occipital) system while searching for places to go, to a mnemonic (temporo-parietal, fronto-hippocampal) system for remembering what actions to perform after TD. Updating of the top-down fronto-parietal network occurred at both TD and switching, the latter likely also being characterized by frontopolar activity. Conclusion/Significance Taken together, these findings show how brain systems complementary interact during real-world PM, and support a more complete model of PM that can be applied to naturalistic PM tasks and that we named PROspective MEmory DYnamic (PROMEDY) model because of its dynamics on both multi-phase iteration and the interactions of distinct neurocognitive networks.
Can variability account for apparent age spreads in OB association colour-magnitude diagrams?

We have investigated the role of photometric variability in causing the apparent age spreads observed in the colour–magnitude diagrams of OB associations. We have found that the combination of binarity, photometric uncertainty and variability on time-scales of a few years is not sufficient to explain the observed spread in either of the OB associations we have studied. Such effects can account for about half the observed spread in the σ Orionis subgroup and about 1/20 of the observed spread in Cep OB3b. This rules out variability caused by stellar rotation and rotation of structures within inner accretion discs as the source of the majority of the apparent age spreads. We also find that the variability tends to move objects parallel to isochrones in V/V − i � colour–magnitude diagrams (CMDs), and thus has little influence on apparent age spreads. We conclude that the remaining unexplained spread either reflects a true spread in the ages of the pre-main-sequence (PMS) objects or arises as a result of longer term variability associated with changes in accretion flow.
Divergent H7 Immunogens Offer Protection from H7N9 Virus Challenge

ABSTRACT The emergence of avian H7N9 viruses in humans in China has renewed concerns about influenza pandemics emerging from Asia. Vaccines are still the best countermeasure against emerging influenza virus infections, but the process from the identification of vaccine seed strains to the distribution of the final product can take several months. In the case of the 2009 H1N1 pandemic, a vaccine was not available before the first pandemic wave hit and therefore came too late to reduce influenza morbidity. H7 vaccines based on divergent isolates of the Eurasian and North American lineages have been tested in clinical trials, and seed strains and reagents are already available and can potentially be used initially to curtail influenza-induced disease until a more appropriately matched H7N9 vaccine is ready. In a challenge experiment in the mouse model, we assessed the efficacy of both inactivated virus and recombinant hemagglutinin vaccines made from seed strains that are divergent from H7N9 from each of the two major H7 lineages. Furthermore, we analyzed the cross-reactive responses of sera from human subjects vaccinated with heterologous North American and Eurasian lineage H7 vaccines to H7N9. Vaccinations with inactivated virus and recombinant hemagglutinin protein preparations from both lineages raised hemagglutination-inhibiting antibodies against H7N9 viruses and protected mice from stringent viral challenges. Similar cross-reactivity was observed in sera of human subjects from a clinical trial with a divergent H7 vaccine. Existing H7 vaccine candidates based on divergent strains could be used as a first line of defense against an H7N9 pandemic. In addition, this also suggests that H7N9 vaccines that are currently under development might be stockpiled and used for divergent avian H7 strains that emerge in the future. IMPORTANCE Sporadic human infections with H7N9 viruses started being reported in China in the early spring of 2013. Despite a significant drop in the number of infections during the summer months of 2013, an increased number of cases has already been reported for the 2013-2014 winter season. The high case fatality rate, the ability to bind to receptors in the human upper respiratory tract in combination with several family clusters, and the emergence of neuraminidase inhibitor-resistant variants that show no loss of pathogenicity and the ability to transmit in animal models have raised concerns about a potential pandemic and have spurred efforts to produce vaccine candidates. Here we show that antigen preparations from divergent H7 strains are able to induce protective immunity against H7N9 infection.
Attentional bias in eating disorders

Objective: To examine the relationship between eating disorders and attentional biases. Method: The first study comprised 23 female patients with clinical eating disorders, women with high levels ofanxiety (n = 19), and three female normal control groups comprising low (n = 31), moderate (n = 21), or high levels of shape concern (n = 23). The second study comprised 82 women with clinical eating disorders and 44 healthy controls. All participants completed measures of eating disorder psychopathology and completed a modified pictorial dot-probe task. Results: In the first study, biases were found for negative eating and neutral weight pictures, and for positive eating pictures in women with eating disorders; these biases were greater than those found in anxious and normal controls. The second study replicated these findings and biases were also found for negative and neutral shape stimuli. Conclusion: It is concluded that future research should establish whether such biases warrant specific therapeutic interventions. © 2007 by Wiley Periodicals, Inc. Int J Eat Disord 2007
High-dose chemotherapy and autologous bone marrow transplantation compared with MACOP-B in aggressive B-cell lymphoma.

BACKGROUND We compared a regimen of six chemotherapeutic agents administered sequentially at high doses, followed by myeloablative treatment and bone marrow transplantation, with a regimen of methotrexate, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin (MACOP-B) as initial or salvage treatment for adults with diffuse large-cell lymphoma. METHODS Ninety-eight eligible patients with diffuse large-cell lymphoma of the B-cell type were randomly assigned to receive either MACOP-B (50 patients) or high-dose sequential therapy (48 patients). The study design allowed for patients in whom the assigned treatment failed to cross over to the other treatment group. RESULTS After a median follow-up of 55 months, the patients given high-dose sequential therapy, as compared with those treated with MACOP-B, had significantly higher rates of complete response (96 percent vs. 70 percent, P=0.001), freedom from disease progression (84 percent vs. 49 percent, P<0.001), freedom from relapse (88 percent vs. 70 percent, P=0.055), and event-free survival (76 percent vs. 49 percent, P=0.004). The difference in overall survival at seven years, which also favored the group assigned to high-dose sequential therapy, was marginally significant (81 percent vs. 55 percent, P=0.09). CONCLUSIONS High-dose sequential therapy is superior to standard-dose MACOP-B for patients with diffuse large-cell lymphoma of the B-cell type.
Full Band Monte-Carlo Device Simulation of 0.1 - 0.5 um Strained-Si P MOSFETs

The transport properties of p-channel MOS transistors with surface channels in strained Si have been studied using a full band Monte Carlo device simulator. It is found that the increase in Ion compared to relaXed Si decreases with reduced chan­ nel length. For strained Si grown on a SiO.7GeO. 3 buffer ·the performance enhance­ ment is 66% in the case of a 0.5p,m de­ vice, whireas it is only 23% in the case of a 0.1p,m transistor.
Backside Process Free Broadband Amplifier MMICs at D-Band and H-Band in 20 nm mHEMT Technology

High gain amplifier MMICs (monolithic microwave integrated circuits) addressing broadband radar and communication applications at the waveguide bands WR-6 (110 - 170 GHz) and WR-3 (220 - 325 GHz) are presented. All circuits are manufactured in the next generation metamorphic high electron mobility transistor (mHEMT) technology featuring 20 nm gate length and a strained 100% InAs channel. The transistors are encapsulated by 0.3 μm and 1.4 μm thick layers of benzocyclobutene (BCB). The 1.4 μm thick BCB layer is used to form shielded thin-film microstrip (TFMS) lines confined at the front-side of the wafer for implementing matching networks. Substrate thinning and backside processing is not required for the function of the amplifiers. The amplifier for WR-6 operates over the whole waveguide band with an average gain of 28 dB. A gain of more than 24 dB was measured for the MMIC from 215 - 290 GHz. All presented MMICs exceed 30% of gain defined bandwidth.
Prefrontal Contributions to Executive Control: fMRI Evidence for Functional Distinctions within Lateral Prefrontal Cortex

The prefrontal cortex (PFC) plays a fundamental role in internally guided behavior. Although it is generally accepted that PFC subserves working memory and executive control operations, it remains unclear whether the subregions within lateral PFC support distinct executive control processes. An event-related fMRI study was implemented to test the hypothesis that ventrolateral and dorsolateral PFC are functionally distinct, as well as to assess whether functional specialization exists within ventrolateral PFC. Participants performed two executive control tasks that differed in the types of control processes required. During rote rehearsal, participants covertly rehearsed three words in the order presented, thus requiring phonological access and maintenance. During elaborative rehearsal, participants made semantic comparisons between three words held in working memory, reordering them from least to most desirable. Thus, in addition to maintenance, elaborative rehearsal required goal-relevant coding of items in working memory ("monitoring") and selection from among the items to implement their reordering. Results revealed that left posterior ventrolateral PFC was active during performance of both tasks, whereas right dorsolateral PFC was differentially engaged during elaborative rehearsal. The temporal characteristics of the hemodynamic responses further suggested that dorsolateral activation lagged ventrolateral activation. Finally, differential activation patterns were observed within left ventrolateral PFC, distinguishing between posterior and anterior regions. These data suggest that anatomically separable subregions within lateral PFC may be functionally distinct and are consistent with models that posit a hierarchical relationship between dorsolateral and ventrolateral regions such that the former monitors and selects goal-relevant representations being maintained by the latter.
Different immunologic profiles characterize HIV infection in highly active antiretroviral therapy-treated and antiretroviral-naïve patients with undetectable viraemia

BackgroundSuppression of human immunodeficiency virus (HIV) replication can be obtained in chronically infected individuals by highly active antiretroviral therapy (HAART) and can also be observed in antiretroviral-naïve patients. The immunological correlates of these two situations were examined. Design and methodsCross-sectional study involving 32 HIV-infected patients with undetectable HIV plasma viraemia (< 500 copies/ml) and either antiretroviral-naïve (n = 14) or undergoing HAART therapy with two nucleoside reverse transcriptase inhibitors (NRTI) plus one (n = 13) or two (n = 5) protease inhibitors (PI). CD4 counts, disease duration, and CDC clinical stage were comparable between the two groups of individuals. Immune parameters (antigen- and mitogen-stimulated proliferation and cytokine production; cytokine mRNA; β chemokine production; HIV coreceptors mRNA) were analysed in all patients. ResultsResults showed immune profiles to be profoundly different in antiretroviral-naïve in comparison with HAART-treated patients. Thus: (1) T-cell proliferation to HIV-specific and HIV-unrelated antigens is potent in antiretroviral-naïve but suppressed in HAART-treated individuals; (2) interleukin-(IL)2, IL-12 and interferon gamma (IFNγ) production is robust in naïve patients; and (3) a high CCR5/low CXCR4 pattern of HIV coreceptors-specific mRNA is observed in naïve but not in HAART-treated patients. In contrast with these observations, no clear differences were detected when β chemokine production by either peripheral blood mononuclear cells or purified CD8+ T-cells was analysed. Results from HAART-treated patients undergoing therapy with one PI and two NRTI or two PI and two NRTI were in very close agreement. ConclusionsThese data suggest that control over HIV replication can be independently achieved by pharmacological or immunologic means. HAART is associated with weaker HIV-specific and -non-specific immune responses.
Elevated Plasma Angiopoietin-2 Levels and Primary Graft Dysfunction after Lung Transplantation

Introduction Primary graft dysfunction (PGD) is a significant contributor to early morbidity and mortality after lung transplantation. Increased vascular permeability in the allograft has been identified as a possible mechanism leading to PGD. Angiopoietin-2 serves as a partial antagonist to the Tie-2 receptor and induces increased endothelial permeability. We hypothesized that elevated Ang2 levels would be associated with development of PGD. Methods We performed a case-control study, nested within the multi-center Lung Transplant Outcomes Group cohort. Plasma angiopoietin-2 levels were measured pre-transplant and 6 and 24 hours post-reperfusion. The primary outcome was development of grade 3 PGD in the first 72 hours. The association of angiopoietin-2 plasma levels and PGD was evaluated using generalized estimating equations (GEE). Results There were 40 PGD subjects and 79 non-PGD subjects included for analysis. Twenty-four PGD subjects (40%) and 47 non-PGD subjects (59%) received a transplant for the diagnosis of idiopathic pulmonary fibrosis (IPF). Among all subjects, GEE modeling identified a significant change in angiopoietin-2 level over time in cases compared to controls (p = 0.03). The association between change in angiopoietin-2 level over the perioperative time period was most significant in patients with a pre-operative diagnosis of IPF (p = 0.02); there was no statistically significant correlation between angiopoietin-2 plasma levels and the development of PGD in the subset of patients transplanted for chronic obstructive pulmonary disease (COPD) (p = 0.9). Conclusions Angiopoietin-2 levels were significantly associated with the development of PGD after lung transplantation. Further studies examining the regulation of endothelial cell permeability in the pathogenesis of PGD are indicated.
Sleep disruptions in parents of children and adolescents with chronic illnesses: prevalence, causes, and consequences.

OBJECTIVE Provide a comprehensive review of the existing literature on the prevalence, causes, and consequences of sleep disruptions in parents of youth with chronic illnesses. METHODS A comprehensive literature search of PsychInfo, MEDLINE, and CINAHL for articles related to sleep in parents of youth with chronic illnesses yielded 59 potential articles, with 19 meeting inclusion criteria. RESULTS Parents of children with eczema were the most commonly studied group. The prevalence of sleep disruptions was 15-86%. Potential causes of parent sleep disruptions included nighttime caregiving, monitoring of the child's illness, and stress related to the child's illness. Consequences included poor sleep quality, depression, and anxiety. CONCLUSIONS Parents of youth with chronic illnesses experience sleep disruptions, providing a potential mechanism to explain elevated rates of negative daytime functioning found in previous studies. To provide interventions and support for these parents, additional research is needed to address the limitations of the existing literature.
A new modeling of human joint lubrication subject to shock loading

This article involves the study of a knee, hip or shoulder joint subject to shock loading or sudden inception of simple shear. Human joints are lubricated by synovial fluid. To properly model joint performance, one must take into account the behavior of this fluid in response to sudden changes. Recent developments in the rheological characterization of polymer fluids suggest an extrapolation of their behavior to biological fluids. Based on a microstructural description of the fluid, it is possible to establish laws of rheological behavior to reproduce shock or sudden inception of shear phenomenon, taking into account large deformation and viscoelastic effects. Consideration of rheological behavior is likely necessary to characterize the response of synovial fluid to shock or sudden variation of applied force. The response of synovial fluid to a sudden overload is analyzed. Modeling of the resulting flow requires the use of nonlinear tensor relationships. The results obtained for various shock amplitude and duration are related to internal parameters of the model, parameters which can be connected to the health and the age of the individual.
Cosmological solutions in multidimensional model with multiple exponential potential

A family of cosmological solutions with (n+1) Ricci-flat spaces in the theory with several scalar fields and multiple exponential potential is obtained when coupling vectors in exponents obey certain relations. Two subclasses of solutions with power-law and exponential behaviour of scale factors are singled out. It is proved that power-law solutions may take place only when coupling vectors are linearly independent and exponential dependence occurs for linearly dependent set of coupling vectors. A subfamily of solutions with accelerated expansion is singled out. A generalized isotropization behaviours of certain classes of general solutions are found. In quantum case exact solutions to Wheeler-DeWitt equation are obtained and special ``ground state" wave functions are considered.
Sampling algorithms for l2 regression and applications

We present and analyze a sampling algorithm for the basic linear-algebraic problem of <i>l</i><inf>2</inf> regression. The <i>l</i><inf>2</inf> regression (or least-squares fit) problem takes as input a matrix <i>A</i> ∈ R<sup><i>n×d</i></sup> (where we assume <i>n</i> ≫ <i>d</i>) and a target vector <i>b</i> ∈ R<sup><i>n</i></sup>, and it returns as output <i>Z</i> = min<inf><i>x</i>∈R<sup><i>d</i></sup></inf> |<i>b - Ax</i>|<inf>2</inf>. Also of interest is <i>x</i><inf><i>opt</i></inf> = <i>A</i>+<i>b</i>, where <i>A</i><sup>+</sup> is the Moore-Penrose generalized inverse, which is the minimum-length vector achieving the minimum. Our algorithm randomly samples <i>r</i> rows from the matrix <i>A</i> and vector <i>b</i> to construct an induced <i>l</i><inf>2</inf> regression problem with many fewer rows, but with the same number of columns. A crucial feature of the algorithm is the nonuniform sampling probabilities. These probabilities depend in a sophisticated manner on the lengths, i.e., the Euclidean norms, of the rows of the left singular vectors of <i>A</i> and the manner in which <i>b</i> lies in the complement of the column space of <i>A</i>. Under appropriate assumptions, we show relative error approximations for both <i>Z</i> and <i>x</i><inf><i>opt</i></inf>. Applications of this sampling methodology are briefly discussed.