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Objective: Solid-pseudopapillary tumor of the pancreas (SPTP) is a rare neoplasm that has been investigated only in individual case series from individual institutions. Here, the goal was to perform a population-based analysis of these rare tumors. Methods: A query of the Surveillance, Epidemiology, and End Results (SEER) database was made for patients with malignant SPTP and pancreatic ductal adenocarcinoma (PDAC) from 2001-2010. The primary outcome measure was five-year overall survival. Cox regression analyses were performed using age, race, gender, tumor location, stage of tumor, and histologic type. Results: 107 patients with SPTP and 53,353 with PDAC were identified for study. Patients with SPTP were younger (p

Plant-feeding insects of the Lygus genus have emerged as a major pest effecting cotton crops in the USA. Here the authors optimize the insecticidal activity of a Bacillus thuringiensis crystal protein and produce transgenic plants that are resistant to feeding damage by Lygusspecies.

In the United States, all previously reported cases of Rickettsia parkeri rickettsiosis have been linked to transmission by the Gulf Coast tick (Amblyomma maculatum). Here we describe 1 confirmed and 1 probable case of R. parkeri rickettsiosis acquired in a mountainous region of southern Arizona, well beyond the recognized geographic range of A. maculatum ticks. The likely vector for these 2 infections was identified as the Amblyomma triste tick, a Neotropical species only recently recognized in the United States. Identification of R. parkeri rickettsiosis in southern Arizona demonstrates a need for local ecologic and epidemiologic assessments to better understand geographic distribution and define public health risk. Education and outreach aimed at persons recreating or working in this region of southern Arizona would improve awareness and promote prevention of tickborne rickettsioses.

Heterozygous mutations in the glucocerebrosidase gene (GBA) represent the strongest common genetic risk factor for Parkinson's disease (PD), the second most common neurodegenerative disorder. However, the molecular mechanisms underlying this association are still poorly understood. Here, we have analyzed ten independent induced pluripotent stem cell (iPSC) lines from three controls and three unrelated PD patients heterozygous for the GBA-N370S mutation, and identified relevant disease mechanisms. After differentiation into dopaminergic neurons, we observed misprocessing of mutant glucocerebrosidase protein in the ER, associated with activation of ER stress and abnormal cellular lipid profiles. Furthermore, we observed autophagic perturbations and an enlargement of the lysosomal compartment specifically in dopamine neurons. Finally, we found increased extracellular α-synuclein in patient-derived neuronal culture medium, which was not associated with exosomes. Overall, ER stress, autophagic/lysosomal perturbations, and elevated extracellular α-synuclein likely represent critical early cellular phenotypes of PD, which might offer multiple therapeutic targets.

A mathematical model is used to estimate material properties from a short duration transient impact force measured by dropping spheres onto rectangular coupons fixed to a dynamic load cell. The contact stress between the dynamic load cell surface and the projectile are modeled using Hertzian contact mechanics. Due to the short impact time relative to the load cell dynamics, an additional Kelvin–Voigt element is included in the model to account for the finite response time of the piezoelectric crystal. Calculations with and without the Kelvin–Voigt element are compared to experimental data collected from combinations of polymeric spheres and polymeric and metallic surfaces. The results illustrate that the inclusion of the Kelvin–Voigt element qualitatively captures the post impact resonance and non-linear behavior of the load cell signal and quantitatively improves the estimation of the Young's elastic modulus and Poisson's ratio. Mathematically, the additional KV element couples one additional differential equation to the Hertzian spring-dashpot equation. The model can be numerically integrated in seconds using standard numerical techniques allowing for its use as a rapid technique for the estimation of material properties. Keywords: Young's modulus, Poisson's ratio, Dynamic load cell

Editor's Note: this Article has been retracted; the Retraction Note is available at https://doi.org/10.1038/s41598-020-80467-y .

Although a growing body of literature demonstrates negative effects of internalized weight bias (IWB), the relationships between IWB and relevant social, psychological, and behavioral variables have not yet been evaluated systematically. The purpose of the present study was to create and assess a model of hypothesized risks and outcomes of IWB. In an online survey, 650 adult males and females completed self-report measures of IWB, self-esteem, weight-related stigma experiences, body-related shame, body satisfaction, societal influence on body image, appearance comparisons, binge eating, distress, and weight-related quality of life. The originally hypothesized model did not provide an adequate fit to the data. Iterative modifications were undertaken, and the resulting model, in which social factors were associated with IWB and body image-related constructs which were in turn associated with psychological and behavioral outcomes, provided excellent fit to the data (CFI > .99, SRMR = .02, and RMSEA = .03). Most model paths were similar for underweight or normal weight participants versus participants with overweight or obesity. This study represents an initial effort at constructing a comprehensive model of IWB that can be further refined in future research and used to help guide the development of related interventions.

We present the case of a female adult with complex cyanotic congenital heart disease who had long-standing thoracic aortic obstruction due to scarring from earlier surgical procedures. She was symptomatic but felt to be too high risk for surgical intervention. With careful planning, she was able to undergo successful stenting of her aorta with subsequent clinical improvement. This case highlights some of the complexities of caring for adults with congenital heart disease and the importance of a thorough understanding of their anatomy and physiology and prior interventions before undertaking interventions.

Background Tibial plateau fractures (TPFs) are frequently associated with motor vehicle accidents, auto-pedestrian crashes and falls. However, hospitals near ski resorts commonly treat TPF resulting from skiing. The soft tissue envelope and original mechanism of injury are important determinants in the decision to proceed with immediate or delayed fixation of the fracture. Our objective was to assess whether immediate (≤24 hours) versus delayed (>24 hours) open reduction internal fixation (ORIF) affected in-hospital outcomes among snow sport participants.Methods This was a retrospective study of patients with isolated TPF who were injured while skiing or snowboarding and treated at a Level III Trauma Center that serves four major ski resorts between 2010 and 2013. Clinical characteristics and in-hospital outcomes were obtained from an existing trauma database. Imaging was reviewed to classify the fracture as high (Schatzker IV–VI) or low (Schatzker I–III) energy. Differences in clinical characteristics and outcomes between immediate and delayed ORIF patients were analyzed with χ2 and Wilcoxon two-sample tests. These analyses were also performed in the high-energy and low-energy fracture populations.Results ORIF was performed on 119 snow sport patients, 93 (78%) immediately. Patients had a median age of 49 years (range 19–70) and were predominantly male (66%). Forty percent sustained a high-energy TPF. No differences were observed between the demographic characteristics, injury severity, Schatzker scores or time from injury to hospital arrival for patients treated immediately versus delayed treatment. Compared with delayed fixation, patients treated immediately had less compartment syndrome (3% vs 27%), needed fewer fasciotomies (6% vs 31%) and had a shorter length of stay (3 vs 6.5 days), p

Various indicators suggest that many students in developing countries are not learning in school. Using Madagascar as a case study, we aimed to: (1) evaluate the effectiveness of education among those enrolled in science and math programs of primary, secondary, and university institutions; and (2) understand barriers to student progression through the education system. To address these aims, we conducted 63 semi-structured interviews in June and August 2012 with science and math teachers in five population centers, across all three levels of the public and private school system. We found that crowded classes, limited resources (pedagogical and infrastructural), an average student age range of seven years per classroom (suggestive of grade repetition and/or late school starting age), and discontinuities in the language of instruction explain why teachers estimated that almost 25% of their students would not finish school. Although most secondary and university teachers taught the sciences only in French, they estimated that just one-third of students could fully understand the language. There were also urban-rural and public-private disparities. Teachers in urban areas were significantly more likely to teach using French than their rural counterparts, while public schools housed significantly larger classes than private institutions. While resource equalisation will help to resolve many of these disparities, improved early training in professional languages and increased local autonomy in designing appropriate curriculums will be necessary to tackle other shortfalls.

Despite their aim to foster belongingness, a small percentage of incoming college students (1%-2%) report feeling excluded (not belonging) during their outdoor orientation program. Feelings of exclusion are often highly consequential to a person transitioning to college. This study explores the experiences of students reporting low levels of belongingness (n= 11) to better understand their experience and to help inform interventions. Thematic analysis using a General Qualitative Approach (GQA) revealed several factors contributing to students' lack of belonging. Findings led to the development of the Belongingness Assessment Model (BAM). This novel approach assesses a lack of belongingness along two scales, isolated vs. generalized lack of belonging and whether the lack of belongingness is bridgeable or unbridgeable. Leader approaches to belongingness are nuanced and may require different interventions based upon the type of exclusion a participant is experiencing.

Tissue inflammation results in the production of numerous reactive oxygen, nitrogen and chlorine species, in addition to the products of lipid and sugar oxidation. Some of these products are capable of chemically modifying amino acids. This in turn results in changes to the structure and function of proteins. Increasing evidence demonstrates that such oxidative post-translational modifications result in the generation of neo-epitopes capable of eliciting both innate and adaptive immune responses. In this paper, we focus on how free radicals and related chemical species generated in inflammatory environments modulate the antigenicity of self-proteins, resulting in immune responses which involve the generation of autoantibodies against key autoantigens in autoimmune diseases. As examples, we will focus on Ro-60 and C1q in systemic lupus erythematosus, along with type-II collagen in rheumatoid arthritis. This review also covers some of the emerging literature which demonstrates that neo-epitopes generated by oxidation are conserved, as exemplified by the evolutionarily conserved pathogen-associated molecular patterns (PAMPs). We discuss how these observations relate to the pathogenesis of both human autoimmune diseases and inflammatory disease, such as atherosclerosis. The potential for these neo-epitopes and the immune responses against them to act as biomarkers or therapeutic targets is also discussed.

Most source attribution studies for Campylobacter use subtyping data based on single isolates from foods and environmental sources in an attempt to draw epidemiological inferences. It has been suggested that subtyping only one Campylobacter isolate per chicken carcass incurs a risk of failing to recognise the presence of clinically relevant, but numerically infrequent, subtypes. To investigate this, between 21 and 25 Campylobacter jejuni isolates from each of ten retail chicken carcasses were subtyped by pulsed-field gel electrophoresis (PFGE) using the two restriction enzymes SmaI and KpnI. Among the 227 isolates, thirteen subtypes were identified, the most frequently occurring subtype being isolated from three carcasses. Six carcasses carried a single subtype, three carcasses carried two subtypes each and one carcass carried three subtypes. Some subtypes carried by an individual carcass were shown to be potentially clonally related. Comparison of C. jejuni subtypes from chickens with isolate subtypes from human clinical cases (n = 1248) revealed seven of the thirteen chicken subtypes were indistinguishable from human cases. None of the numerically minor chicken subtypes were identified in the human data. Therefore, typing only one Campylobacter isolate from individual chicken carcasses may be adequate to inform Campylobacter source attribution.

Understanding how humans adapt gait mechanics for a wide variety of locomotor tasks is important for inspiring the design of robotic, prosthetic and wearable assistive devices. We aimed to elicit the mechanical adjustments made to leg joint functions that are required to generate accelerative walking and running, using metrics with direct relevance to device design. Twelve healthy male participants completed constant speed (CS) walking and running and emulated acceleration (ACC) trials on an instrumented treadmill. External force and motion capture data were combined in an inverse dynamics analysis. Ankle, knee and hip joint mechanics were described and compared using angles, moments, powers and normalized functional indexes that described each joint as relatively more: spring, motor, damper or strut-like. To accelerate using a walking gait, the ankle joint was switched from predominantly spring-like to motor-like, while the hip joint was maintained as a motor, with an increase in hip motor-like function. Accelerating while running involved no change in the primary function of any leg joint, but involved high levels of spring and motor-like function at the hip and ankle joints. Mechanical adjustments for ACC walking were achieved primarily via altered limb positioning, but ACC running needed greater joint moments.

Although prior research has suggested that some students may be averse to taking out loans to finance their college education, there is little empirical evidence showing the extent to which loan aversion exists or how it affects different populations of students. This study provides the first large-scale quantitative evidence of levels of loan aversion in the United States. Using survey data collected on more than 6,000 individuals, we examine the frequency of loan aversion in three distinct populations. Depending on the measure, between 20 and 40% of high school seniors exhibit loan aversion with lower rates among community college students and adults not in college. Women are less likely to express loan-averse attitudes than men, and Hispanic respondents are more likely to be loan averse than White respondents.

Historically, admissions committees for biomedical Ph.D. programs have heavily weighed GRE scores when considering applications for admission. The predictive validity of GRE scores on graduate student success is unclear, and there have been no recent investigations specifically on the relationship between general GRE scores and graduate student success in biomedical research. Data from Vanderbilt University Medical School's biomedical umbrella program were used to test to what extent GRE scores can predict outcomes in graduate school training when controlling for other admissions information. Overall, the GRE did not prove useful in predicating who will graduate with a Ph.D., pass the qualifying exam, have a shorter time to defense, deliver more conference presentations, publish more first author papers, or obtain an individual grant or fellowship. GRE scores were found to be moderate predictors of first semester grades, and weak to moderate predictors of graduate GPA and some elements of a faculty evaluation. These findings suggest admissions committees of biomedical doctoral programs should consider minimizing their reliance on GRE scores to predict the important measures of progress in the program and student productivity.

Background. Muscles not only shorten during contraction to perform mechanical work, but they also bulge radially because of the isovolumetric constraint on muscle fibres. Muscle bulging may have important implications for muscle performance, however quantifying three-dimensional (3D) muscle shape changes in human muscle is problematic because of difficulties with sustaining contractions for the duration of an in vivo scan. Although two-dimensional ultrasound imaging is useful for measuring local muscle deformations, assumptions must be made about global muscle shape changes, which could lead to errors in fully understanding the mechanical behaviour of muscle and its surrounding connective tissues, such as aponeurosis. Therefore, the aims of this investigation were (a) to determine the intra-session reliability of a novel 3D ultrasound (3DUS) imaging method for measuring in vivo human muscle and aponeurosis deformations and (b) to examine how contraction intensity influences in vivo human muscle and aponeurosis strains during isometric contractions. Methods. Participants (n = 12) were seated in a reclined position with their left knee extended and ankle at 90° and performed isometric dorsiflexion contractions up to 50% of maximal voluntary contraction. 3DUS scans of the tibialis anterior (TA) muscle belly were performed during the contractions and at rest to assess muscle volume, muscle length, muscle cross-sectional area, muscle thickness and width, fascicle length and pennation angle, and central aponeurosis width and length. The 3DUS scan involved synchronous B-mode ultrasound imaging and 3D motion capture of the position and orientation of the ultrasound transducer, while successive cross-sectional slices were captured by sweeping the transducer along the muscle. Results. 3DUS was shown to be highly reliable across measures of muscle volume, muscle length, fascicle length and central aponeurosis length (ICC ≥ 0.98, CV < 1%). The TA remained isovolumetric across contraction conditions and progressively shortened along its line of action as contraction intensity increased. This caused the muscle to bulge centrally, predominantly in thickness, while muscle fascicles shortened and pennation angle increased as a function of contraction intensity. This resulted in central aponeurosis strains in both the transverse and longitudinal directions increasing with contraction intensity. Discussion. 3DUS is a reliable and viable method for quantifying multidirectional muscle and aponeurosis strains during isometric contractions within the same session. Contracting muscle fibres do work in directions along and orthogonal to the muscle’s line of action and central aponeurosis length and width appear to be a function of muscle fascicle shortening and transverse expansion of the muscle fibres, which is dependent on contraction intensity. How factors other than muscle force change the elastic mechanical behaviour of the aponeurosis requires further investigation.

Sphingolipids are structurally diverse and their metabolic pathways highly complex, which makes it difficult to follow all of the subspecies in a biological system, even using “lipidomic” approaches. This report describes a method to use transcriptomic data to visualize and predict potential differences in sphingolipid composition, and it illustrates its use with published data for cancer cell lines and tumors. In addition, several novel sphingolipids that were predicted to differ between MDA-MB-231 and MCF7 cells based on published microarray data for these breast cancer cell lines were confirmed by mass spectrometry. For the data that we were able to find for these comparisons, there was a significant match between the gene expression data and sphingolipid composition (P < 0.001 by Fisher's exact test). Upon considering the large number of gene expression datasets produced in recent years, this simple integration of two types of “omic” technologies (“transcriptomics” to direct “sphingolipidomics”) might facilitate the discovery of useful relationships between sphingolipid metabolism and disease, such as the identification of new biomarkers.

Human-modified habitats are expanding rapidly; many tropical countries have highly fragmented and degraded forests. Preserving biodiversity in these areas involves protecting species-like frugivorous bats-that are important to forest regeneration. Fruit bats provide critical ecosystem services including seed dispersal, but studies of how their diets are affected by habitat change have often been rather localized. This study used stable isotope analyses (δ15N and δ13C measurement) to examine how two fruit bat species in Madagascar, Pteropus rufus (n = 138) and Eidolon dupreanum (n = 52) are impacted by habitat change across a large spatial scale. Limited data for Rousettus madagascariensis are also presented. Our results indicated that the three species had broadly overlapping diets. Differences in diet were nonetheless detectable between P. rufus and E. dupreanum, and these diets shifted when they co-occurred, suggesting resource partitioning across habitats and vertical strata within the canopy to avoid competition. Changes in diet were correlated with a decrease in forest cover, though at a larger spatial scale in P. rufus than in E. dupreanum. These results suggest fruit bat species exhibit differing responses to habitat change, highlight the threats fruit bats face from habitat change, and clarify the spatial scales at which conservation efforts could be implemented.

Wild meat trade constitutes a threat to many animal species. Understanding the commodity chain of wild animals (hunting, transportation, trade, consumption) can help target conservation initiatives. Wild meat commodity chain research has focused on the formal trade and less on informal enterprises, although informal enterprises contribute to a large portion of the wild meat trade in sub-Saharan Africa. We aimed to provide a more comprehensive understanding of the formal and informal components of these commodity chains by focusing on the mammalian wild meat trade in Madagascar. Our objectives were to: (1) identify hunting strategies used to capture different wild mammals; (2) analyze patterns of movement of wild meat from the capture location to the final consumer; (3) examine wild meat prices, volumes, and venues of sale; and (4) estimate the volume of wild meat consumption. Data were collected in May-August 2013 using semi-structured interviews with consumers (n = 1343 households, 21 towns), meat-sellers (n = 520 restaurants, open-air markets stalls, and supermarkets, 9 towns), and drivers of inter-city transit vehicles (n = 61, 5 towns). We found that: (1) a wide range of hunting methods were used, though prevalence of use differed by animal group; (2) wild meat was transported distances of up to 166 km to consumers, though some animal groups were hunted locally (

Plant-herbivore interactions influence the establishment context of plant species, as herbivores alter the community context in which individual species establish, and the spatial relationship between individuals and their source population as plants invade. This relationship can be described using an establishment kernel, which takes into account movement through seed dispersal, and subsequent establishment of adults. Mammalian herbivores are hypothesized to influence plant population growth and establishment through a combination of consumption of seeds and seedlings, and movement of seeds. While the movement abilities of plants are well known, we have very few empirical mechanistic tests of how biotic factors like mammalian herbivores influence this spread potential. As herbivores of all sizes are abundant on the landscape, we asked the question, how do mammalian herbivores influence the population growth, spatial establishment, and the community establishment context of an early-recruiting native prairie legume, Chamaecrista fasciculata? We planted C. fasciculata in source populations within a four-acre tallgrass prairie restoration in plots with and without herbivores, and monitored its establishment with respect to distance from the source populations. We found that herbivores decreased population growth, and decreased the mean and range establishment distance. Additionally, C. fasciculata established more often without herbivores, and when surrounded by weedy, annual species. Our results provide insight into how the interactions between plants and herbivores can alter the spatial dynamics of developing plant communities, which is vital for colonization and range spread with fragmentation and climate change. Mammalian herbivores have the potential to both slow rates of establishment, but also determine the types of plant communities that surround invading species. Therefore, it is essential to consider the herbivore community when attempting to restore functioning plant communities.

Humans have altered the biotic and abiotic environmental conditions of most organisms. In some cases, such as intensive agriculture, an organism's entire ecosystem is converted to novel conditions. Thus, it is striking that some species continue to thrive under such conditions. The prairie deer mouse (Peromyscus maniculatus bairdii) is an example of such an organism, and so we sought to understand what role evolutionary adaptation played in the success of this species, with particular interest in adaptations to novel foods. In order to understand the evolutionary history of this species' masticatory structures, we examined the maxilla, zygomatic plate, and mandible of historic specimens collected prior to 1910 to specimens collected in 2012 and 2013. We found that mandibles, zygomatic plates, and maxilla have all changed significantly since 1910, and that morphological development has shifted significantly. We present compelling evidence that these differences are due to natural selection as a response to a novel and ubiquitous food source, waste grain (corn, Zea mays and soybean, Glycine max).

Brain wave activity is known to correlate with decrements in behavioral performance as individuals enter states of fatigue, boredom, or low alertness. Many BCI technologies are adversely affected by these changes in user state, limiting their application and constraining their use to relatively short temporal epochs where behavioral performance is likely to be stable. Incorporating a passive BCI that detects when the user is performing poorly at a primary task, and adapts accordingly may prove to increase overall user performance. Here, we explore the potential for extending an established method to generate continuous estimates of behavioral performance from ongoing neural activity; evaluating the extended method by applying it to the original task domain, simulated driving; and generalizing the method by applying it to a BCI-relevant perceptual discrimination task. Specifically, we used EEG log power spectra and sequential forward floating selection (SFFS) to estimate endogenous changes in behavior in both a simulated driving task and a perceptual discrimination task. For the driving task the average correlation coefficient between the actual and estimated lane deviation was 0.37 ± 0.22 (mean ± std). For the perceptual discrimination task we generated estimates of accuracy, reaction time, and button press duration for each participant. The correlation coefficients between the actual and estimated behavior were similar for these three metrics (accuracy = 0.25 ± 0.37, reaction time = 0.33 ± 0.23, button press duration = 0.36 ± 0.30). These findings illustrate the potential for modeling time-on-task decrements in performance from concurrent measures of neural activity.

Several studies have examined sirolimus-based immune suppression for the prevention of graft-versus-host disease after allogeneic hematopoietic cell transplantation, but little is known regarding its effects on quality of life. The current study reports on changes in quality of life to Day 360 in a randomized phase II trial of sirolimus and tacrolimus versus methotrexate and tacrolimus. Quality of life was assessed prior to transplant and on Days 30, 90, 180, 270, and 360 with the Functional Assessment of Cancer Therapy – Bone Marrow Transplant Trial Outcome Index. Random effects models examined the effects of study arm on change in Trial Outcome Index scores from Day 30 to 360, controlling for base-line Trial Outcome Index. The sirolimus/tacrolimus arm (n=37) showed less improvement in Trial Outcome Index scores over time compared to the methotrexate/tacrolimus arm (n=34) (P=0.02). Patients receiving sirolimus and tacrolimus were more likely to endorse nausea and a lack of energy over time (PS≤0.01). These data suggest that sirolimus-based immune suppression is associated with less improvement in quality of life in the first year post-transplant compared to methotrexate/tacrolimus. Quality of life differences may be due to increased fatigue and nausea in patients treated with sirolimus. These findings should be considered in the clinical management of patients treated with sirolimus. (Clinicaltrials.gov identifier:00803010).

Versions of cognitive behavioral therapy (Coping Cat, CC; Behavioral Interventions for Anxiety in Children with Autism, BIACA) have shown efficacy in treating anxiety among youth with autism spectrum disorder. Measures of efficacy have been primarily nomothetic symptom severity assessments. The current study examined idiographic coping outcomes in the Treatment of Anxiety in Autism Spectrum Disorder study (N = 167). Longitudinal changes in coping with situations individualized to youth fears (Coping Questionnaire) were examined across CC, BIACA and treatment as usual (TAU) in a series of multilevel models. CC and BIACA produced significantly greater improvements than TAU in caregiver-reported coping. Youth report did not reflect significant differences. Results show the efficacy of CC and BIACA in improving idiographic caregiver-, but not youth-, reported youth coping., Author(s): Lesley A. Norris [sup.1] [sup.6] , Jonathan C. Rabner [sup.1] , Eric A. Storch [sup.2] , Jeffrey J. Wood [sup.3] , Connor Kerns [sup.4] , Adam B. Lewin [sup.5] [...]