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How instructional sequences guide learning processes are often regarded as a neutral act. However, does designing instruction carry a politics? This investigation explores how instruction is made as a pedagogical object. The purpose is to explore the epistemological principles and conceptual framework that produce instruction's formalized pedagogical processes, each of which carries uncontested cultural and political aspects. Through textual analysis, the article considers theoretically and historically the problem of how instruction's design entangles people, power, and technology to operate as social technology, making up human kinds when instruction is designed as rule-bound programming—as an algorithm. Such algorithms engineer cultural action to engineer more harmonious human relations, embodying a greater political project that closes a technocultural lag, ameliorating human deficiencies while producing social exclusion and inequality. [ABSTRACT FROM AUTHOR]

In this study, the temperature dependence of the carbon/polyamide 410 composite's heat capacity, thermal expansion, density, and thermal conductivity was investigated. The results demonstrated that the specific heat capacity of the C/PA410 composite increases with temperature, with major transitions observed at the glass transition (Tg) and melting (Tm) temperatures. Due to the presence of fibers, the CTE values in the fiber direction of C/PA410 specimens were one order of magnitude smaller than in the transverse direction. The density measurements reveal that as temperature rises, volume increases, causing density to decrease. The heat diffusivity of the C/PA410 composite was measured using the laser flash technique, which was then used to calculate thermal conductivity. The results show that the average thermal conductivity in the fiber direction increases linearly with temperature, while in the transverse direction it increases linearly with temperature up to 50 °C and then becomes constant between 50 °C and 100 °C. [ABSTRACT FROM AUTHOR]

Understanding the effect of task compared to rest on detecting stroke-related network abnormalities will inform efforts to optimize detection of such abnormalities. The goal of this work was to determine whether connectivity measures obtained during an overt task are more effective than connectivity obtained during a "resting" state for detecting stroke-related changes in network function of the brain. This study examined working memory, discrete pedaling, continuous pedaling and language tasks. Functional magnetic resonance imaging was used to examine regional and inter-regional brain network function in 14 stroke and 16 control participants. Independent component analysis was used to identify 149 regions of interest (ROI). Using the inter-regional connectivity measurements, the weighted sum was calculated across only regions associated with a given task. Both inter-regional connectivity and regional connectivity were greater during each of the tasks as compared to the resting state. The working memory and discrete pedaling tasks allowed for detection of stroke-related decreases in inter-regional connectivity, while the continuous pedaling and language tasks allowed for detection of stroke-related enhancements in regional connectivity. These observations illustrate that task-based functional connectivity allows for detection of stroke-related changes not seen during resting states. In addition, this work provides evidence that tasks emphasizing different cognitive domains reveal different aspects of stroke-related reorganization. We also illustrate that within the motor domain, different tasks can reveal inter-regional or regional stroke-related changes, in this case suggesting that discrete pedaling required more central drive than continuous pedaling. [ABSTRACT FROM AUTHOR]

Clinical guidelines recommend intensive community care service treatment (ICCS) to reduce adolescent psychiatric inpatient care. We have previously reported that the addition of ICCS led to a substantial decrease in hospital use and improved school re-integration. The aim of this study is to undertake a randomised controlled trial (RCT) comparing an inpatient admission followed by an early discharge supported by ICCS with usual inpatient admission (treatment as usual; TAU). In this paper, we report the impact of ICCS on self-harm and other clinical and educational outcomes. 106 patients aged 12–18 admitted for psychiatric inpatient care were randomised (1:1) to either ICCS or TAU. Six months after randomisation, we compared the two treatment arms on the number and severity of self-harm episodes, the functional impairment, severity of psychiatric symptoms, clinical improvement, reading and mathematical ability, weight, height and the use of psychological therapy and medication. At six-month follow-up, there were no differences between the two groups on most measures. Patients receiving ICCS were significantly less likely to report multiple episodes (five or more) of self-harm (OR = 0.18, 95% CI: 0.05–0.64). Patients admitted to private inpatient units spent on average 118.4 (95% CI: 28.2–208.6) fewer days in hospitals if they were in the ICCS group compared to TAU. The addition of ICCS to TAU may lower the risk of multiple self-harm and may reduce the duration of inpatient stay, especially in those patients admitted for private care. Early discharge with ICCS appears to be a viable alternative to standard inpatient treatment. [ABSTRACT FROM AUTHOR]

Despite the higher specific mechanical properties and the lower density of polymeric foams, these materials present cumulative damage behaviour that implies in the second and successive impacts, their mechanical properties decrease drastically. However, cork and cork agglomerates have the ability to absorb multiple impacts so they could be a more suitable material in some products, such as bumpers and helmets. This article is focused on the study of five different cork agglomerates and a natural cork under four different maximum deformations subjected to four consecutive compression loading cycles. Main diagrams, such as the stress–strain, energy density and efficiency, and the variation in diverse parameters, such as the absorbed energy density and maximum efficiency, were investigated and compared with an expanded polystyrene foam. [ABSTRACT FROM AUTHOR]

Cork and cork agglomerates could be suitable replacements for petroleum-based polymeric foams due to their similar internal structure of cells and grains. Additionally, cork products have a renewable origin and are recyclable. Despite these notable properties, few studies have analysed the mechanical properties, especially the specific properties, of these materials under compressive loads. Moreover, although efficiency, ideality, and energy-normalized stress diagrams are commonly used for polymeric foams and 3D-printed lattice structures, these types of diagrams are not yet applied to cork products. It must be highlighted that efficiency diagrams are plotted only against nonspecific properties so, this article proposes additionally the use of nonspecific properties to compare materials not only in terms of properties per unit volume instead but also in terms of properties per unit mass that is more suitable for certain applications in which the weight is crucial. The materials studied herein include three different white cork agglomerates, a brown cork agglomerate, a black cork agglomerate, natural cork, and expanded polystyrene foam, which are subjected to quasi-static compressive loads. [ABSTRACT FROM AUTHOR]

Expanded polystyrene (EPS) is a material that is widely used in energy absorbing applications, especially in helmets, despite its non-renewable origin. Cork and its derivatives, however, are proposed as a substitute for polystyrene foam (EPS) due to their renewable origin and their easy recyclability. In spite of the low-environmental footprint of cork and its derivatives, there is insufficient data on their mechanical behaviour. Consequently, under dynamic and quasi-static loads, four different-density EPS, a natural cork material and five different cork products with different grain sizes and heat treatments were tested. They were compared in terms of their stress–strain and specific stress–strain curve, their volumetric capability to absorb energy, their specific energy, average decelerations and peak deceleration. Finally, EPS foams cannot recover their initial shape upon deformation due to their low resilience capability. This is especially important in applications such as helmets, which are bound to be subjected to multiple impacts. However, cork and its products could have this capability for resilience and would therefore be more suitable for certain applications. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate five hypothesized mechanisms of causation between depression and condomless sex with ≥ 2 partners (CLS2+) among gay, bisexual, and other men who have sex with men (GBMSM), involving alternative roles of self-efficacy for sexual safety and recreational drug use. Data were from the AURAH cross-sectional study of 1340 GBMSM attending genitourinary medicine clinics in England (2013–2014). Structural equation modelling (SEM) was used to investigate which conceptual model was more consistent with the data. Twelve percent of men reported depression (PHQ-9 ≥ 10) and 32% reported CLS2+ in the past 3 months. AURAH data were more consistent with the model in which depression was considered to lead to CLS2+ indirectly via low self-efficacy for sexual safety (indirect Beta = 0.158; p < 0.001) as well as indirectly via higher levels of recreational drug use (indirect Beta = 0.158; p < 0.001). SEM assists in understanding the relationship between depression and CLS among GBMSM. [ABSTRACT FROM AUTHOR]

Helminth parasites have been shown to have systemic effects in the host. Using shotgun metagenomic sequencing, we characterise the gut microbiome and resistome of 113 Zimbabwean preschool-aged children (1–5 years). We test the hypothesis that infection with the human helminth parasite, Schistosoma haematobium, is associated with changes in gut microbial and antimicrobial resistance gene abundance/diversity. Here, we show that bacteria phyla Bacteroidetes, Firmicutes, Proteobacteria, and fungi phyla Ascomycota, Microsporidia, Zoopagomycota dominate the microbiome. The abundance of Proteobacteria, Ascomycota, and Basidiomycota differ between schistosome-infected versus uninfected children. Specifically, infection is associated with increases in Pseudomonas, Stenotrophomonas, Derxia, Thalassospira, Aspergillus, Tricholoma, and Periglandula, with a decrease in Azospirillum. We find 262 AMR genes, from 12 functional drug classes, but no association with individual-specific data. To our knowledge, we describe a novel metagenomic dataset of Zimbabwean preschool-aged children, indicating an association between urogenital schistosome infection and changes in the gut microbiome. Osakunor et al. show that infection of Zimbabwean preschool-aged children with Schistosoma haematobium correlates with abundance changes in Pseudomonas, Stenotrophomonas, Derxia, Thalassospira, Aspergillus, Tricholoma, Periglandula, and Azospirillum. This study provides a microbiome and resistome dataset of African preschool-aged children. [ABSTRACT FROM AUTHOR]

Background/objectives: Obstruction of the nasoenteral tube is one of the complications of enteral nutrition therapy, and its causes and frequency of occurrence are not well understood. To evaluate the causes of enteral nutrition feeding tube obstruction. To study the time elapsed between the beginning of the nutrition therapy and the obstruction of the tube.Subjects/methods: This was a retrospective cohort study of 1170 patients aged 18 years or older who were hospitalized at Sírio-Libanês Hospital between January 2015 and October 2017, and who were undergoing enteral nutrition therapy delivered using an infusion pump through a nasogastric or nasoenteral tube. The study population included 683 (58%) men and 487 (42%) women. The median age was 79 years. Of these, 1084 patients received enteral nutrition and medication through the feeding tube, and 86 received medication alone. Variables investigated as causes of feeding tube obstruction were the administration of medication through the tube, type of diet, and use of symbiotics.Results: Obstruction rates were 4% for up to 40 days of observation and 8% for the total observation time. The time for obstruction of 10% of the tubes in patients receiving rivaroxaban, linagliptin, metformin, and nystatin was 16, 19, 20, and 28 days, respectively.Conclusions: The main cause of nasoenteral tube obstruction (odds ratio) was the combination of metformin (2.0), nystatin (3.1), linagliptin (4.3), rivaroxaban (2.4), and a high-protein diet (1.9). Overall, proper tube care and strict compliance with tubal drug delivery guidelines can result in low tube obstruction rates. [ABSTRACT FROM AUTHOR]

The business model concept has received strong interest among both practitioners and academics. As recent reviews of the literature on business models indicate, the number of articles that deepen the understanding of the role and nature of the business model concept as well as its antecedents and consequences has grown rapidly in the last years (e.g., Zott et al. in Journal of Management, 37(4), 1019-1042, 2011; Wirtz et al. in Long Range Planning, 49(1), 36-54, 2016). Yet, this substantial body of work that covers multiple perspectives and includes studies in a variety of contexts and settings has so far produced a fragmented research landscape that has largely developed in silos. Drawing on configuration theory (Ketchen et al. in Academy of Management Journal, 36(6), 1278-1313, 1993; Meyer et al. in Academy of Management Journal, 36(6), 1175-1195, 1993) and recent literature adopting a configurational approach (Fiss in Academy of Management Journal, 54(2), 393-420, 2011; Leischnig et al. in Journal of Business Research, 69(9), 3576-3583, 2016a), the purpose of this article is to discuss how marketing research and practice may benefit from a business model perspective and configurational thinking. We suggest that a business model can fruitfully be understood as a configuration of components embracing multiple domains and whose interdependent and interconnected structures influence the extent to which a firm can achieve strategic objectives and superior performance. We discuss which elements in business models are particularly linked to the field of marketing and how the role of these elements may differ in alternative configurations of business models. We conclude with an agenda for researchers from marketing and related disciplines that identifies avenues for further research on business models as configurations. [ABSTRACT FROM AUTHOR]

Helminth parasites defy immune exclusion through sophisticated evasion mechanisms, including activation of host immunosuppressive regulatory T (Treg) cells. The mouse parasite Heligmosomoides polygyrus can expand the host Treg population by secreting products that activate TGF-β signalling, but the identity of the active molecule is unknown. Here we identify an H. polygyrus TGF-β mimic (Hp-TGM) that replicates the biological and functional properties of TGF-β, including binding to mammalian TGF-β receptors and inducing mouse and human Foxp3+ Treg cells. Hp-TGM has no homology with mammalian TGF-β or other members of the TGF-β family, but is a member of the complement control protein superfamily. Thus, our data indicate that through convergent evolution, the parasite has acquired a protein with cytokine-like function that is able to exploit an endogenous pathway of immunoregulation in the host. [ABSTRACT FROM AUTHOR]

Partitioned pricing (PP) has received increased attention in both managerial practice and academic literature. The fragmented nature of existing research, terminological and conceptual inconsistencies, and ambiguous findings regarding performance implications of PP underscore the need for an organization of the PP literature. This article provides four major contributions to the literature. First, it develops a new definition of PP based on a critical evaluation of the current body of literature and an analysis of key characteristics of the concept. Second, this article discusses the primary theoretical perspectives used to explain PP, which provides insights into the theoretical foundation of the concept and impetus for future studies on PP. Third, this article presents a review of the state-of-the-art in research on PP and provides managers with guidelines about when and how to apply this pricing tactic. Finally, this article identifies overarching limitations of prior PP research and outlines avenues for further research. [ABSTRACT FROM AUTHOR]

To date, intrinsic obstructions of the duodenum have been explained by the "solid core" theory, described by Tandler in 1902 (Morphol Jahrb 29:187-216, 1902). This study aimed to evaluate the epithelial occlusion of rat duodenum during embryonic development, through optical microscopy and computerized three-dimensional reconstruction. The Wistar rat embryos used in this study had 13, 14, 15, and 16 days of gestation. This corresponds to human embryos with 33, 40, 44, and 52 days of development, which is between the fifth and eighth week. The study included 12 embryos studied by optical microscopy, and four by three-dimensional reconstruction (those with 13, 14, 15, and 16 days). Through optical microscopy, an intense epithelial proliferation was observed in the gestation embryo of 13 days, with no occlusion of the opening of the duodenum. In the embryos with 14, 15, and 16 days of gestation, an increase in diameter of the duodenum was observed along with intestinal development. Through three-dimensional reconstruction, it was observed that the opening of the digestive tube of rat embryos with 13-16 days of gestation is never obstructed by epithelial proliferation, although it may follow a sinuous path. This study concludes that the "solid core" phase described by Tandler does not occur in the embryonic development of rat duodenum. [ABSTRACT FROM AUTHOR]

Image-based computational fluid dynamics (CFD) studies conducted at rest have shown that atherosclerotic plaque in the thoracic aorta (TA) correlates with adverse wall shear stress (WSS), but there is a paucity of such data under elevated flow conditions. We developed a pedaling exercise protocol to obtain phase contrast magnetic resonance imaging (PC-MRI) blood flow measurements in the TA and brachiocephalic arteries during three-tiered supine pedaling at 130, 150, and 170 % of resting heart rate (HR), and relate these measurements to non-invasive tissue oxygen saturation $$(\hbox {StO}_{2})$$ acquired by near-infrared spectroscopy (NIRS) while conducting the same protocol. Local quantification of WSS indices by CFD revealed low time-averaged WSS on the outer curvature of the ascending aorta and the inner curvature of the descending aorta (dAo) that progressively increased with exercise, but that remained low on the anterior surface of brachiocephalic arteries. High oscillatory WSS observed on the inner curvature of the aorta persisted during exercise as well. Results suggest locally continuous exposure to potentially deleterious indices of WSS despite benefits of exercise. Linear relationships between flow distributions and tissue oxygen extraction calculated from $$\hbox {StO}_{2}$$ were found between the left common carotid versus cerebral tissue $$(r^{2}=0.96)$$ and the dAo versus leg tissue $$(r^{2}=0.87)$$ . A resulting six-step procedure is presented to use NIRS data as a surrogate for exercise PC-MRI when setting boundary conditions for future CFD studies of the TA under simulated exercise conditions. Relationships and ensemble-averaged PC-MRI inflow waveforms are provided in an online repository for this purpose. [ABSTRACT FROM AUTHOR]

This paper proposes a methodology to determine wall thickness distributions in thermoformed products derived from in-situ surface strain measurements obtained with stereo digital image correlation (DIC), under the assumption of material incompressibility. Wall thickness equations are derived for the Green-Lagrange, Hencky, Biot, logarithmic Euler-Almansi and Euler-Almansi strain definitions and validated with an analytic example. The equations are then used to calculate the wall thickness from digital image correlations with both a commercial software (VIC-3D, version 2012) and an academic software (MatchID3D). Obviously, the choice of the strain definition in the correlation software should not influence the resulting wall thickness values. The comparison reveals that the wall thickness values prove to be identical, regardless of the strain definition that was used, and manual measurements show the validity of the DIC based results. It was also found that, when using VIC-3D version 2009, an earlier release in the software series of Correlated Solutions, all but the Green-Lagrange strain definition bring forth unrealistic minimum principal strain values, resulting in different values for the wall thickness. [ABSTRACT FROM AUTHOR]

The protozoan parasites Trypanosoma brucei spp. cause important human and livestock diseases in sub-Saharan Africa. In mammalian blood, two developmental forms of the parasite exist: proliferative 'slender' forms and arrested 'stumpy' forms that are responsible for transmission to tsetse flies. The slender to stumpy differentiation is a density-dependent response that resembles quorum sensing in microbial systems and is crucial for the parasite life cycle, ensuring both infection chronicity and disease transmission. This response is triggered by an elusive 'stumpy induction factor' (SIF) whose intracellular signalling pathway is also uncharacterized. Laboratory-adapted (monomorphic) trypanosome strains respond inefficiently to SIF but can generate forms with stumpy characteristics when exposed to cell-permeable cAMP and AMP analogues. Exploiting this, we have used a genome-wide RNA interference library screen to identify the signalling components driving stumpy formation. In separate screens, monomorphic parasites were exposed to 8-(4-chlorophenylthio)-cAMP (pCPT-cAMP) or 8-pCPT-2′-O-methyl-5′-AMP to select cells that were unresponsive to these signals and hence remained proliferative. Genome-wide Ion Torrent based RNAi target sequencing identified cohorts of genes implicated in each step of the signalling pathway, from purine metabolism, through signal transducers (kinases, phosphatases) to gene expression regulators. Genes at each step were independently validated in cells naturally capable of stumpy formation, confirming their role in density sensing in vivo. The putative RNA-binding protein, RBP7, was required for normal quorum sensing and promoted cell-cycle arrest and transmission competence when overexpressed. This study reveals that quorum sensing signalling in trypanosomes shares similarities to fundamental quiescence pathways in eukaryotic cells, its components providing targets for quorum-sensing interference-based therapeutics. [ABSTRACT FROM AUTHOR]

Polymeric matrix composites are susceptible to degradation and material properties changes if subjected to low-temperature environmental conditions. This paper attempts to present a study on effective coefficient of thermal expansion for various hybrid carbon fibers/glass fibers polymeric composite structures previously subjected to low-temperature environmental conditioning. The hybrid composite architectures were made from various layers of glass mat and/or glass woven embedded along with layers of unidirectional carbon fibers into a polymeric matrix. The samples were preconditioned to a low-temperature environment at a constant temperature of −35 °C for 1-week long, 24 h/day. The instantaneous CTE and thermal strain fields were recorded with a DIL 402 PC/1 dilatometer from Netzsch GmbH (Germany) by setting a monotonically linear rise of temperature from 20 to 250 °C, at a rate of 1 °C min. The experimentally retrieved data were compared with the values obtained by running a micromechanical-based approach simulation on a representative volume element. [ABSTRACT FROM AUTHOR]