New sensitivity of LHC measurements to composite dark matter models

We present sensitivity of LHC differential cross-section measurements to so-called "stealth dark matter" scenarios occurring in an SU(N) dark gauge group, where constituents are charged under the Standard Model and N=2 or 4. The low-energy theory contains mesons which can be produced at the LHC, and a scalar baryon dark matter (DM) candidate which cannot. We evaluate the impact of LHC measurements on the dark meson masses. Using existing lattice results, we then connect the LHC explorations to DM phenomenology, in particular considering direct-detection experiments. We show that current LHC measurements constrain DM masses in the region of 10 TeV. We discuss potential pathways to explore these models further at the LHC

Real-time data coupling for hybrid testing in a geotechnical centrifuge

Geotechnical centrifuge models necessarily involve simplifications compared to the full-scale scenario under investigation. In particular, structural systems (e.g. buildings or foundations) generally can’t be replicated such that complex full-scale characteristics are obtained. Hybrid testing offers the ability to combine capabilities from physical and numerical modelling to overcome some of the experimental limitations. In this paper, the development of a coupled centrifuge-numerical model (CCNM) pseudo-dynamic hybrid test for the study of tunnel-building interaction is presented. The methodology takes advantage of the relative merits of centrifuge tests (modelling soil behaviour and soil-pile interactions) and numerical simulations (modelling building deformations and load redistribution), with pile load and displacement data being passed in real-time between the two model domains. To appropriately model the full-scale scenario, a challenging force-controlled system was developed (the first of its kind for hybrid testing in a geotechnical centrifuge). The CCNM application can accommodate simple structural frame analyses as well as more rigorous simulations conducted using the finite element analysis software ABAQUS, thereby extending the scope of application to non-linear structural behaviour. A novel data exchange method between ABAQUS and LabVIEW is presented which provides a significant enhancement compared to similar hybrid test developments. Data are provided from preliminary tests which highlight the capabilities of the system to accurately model the global tunnel-building interaction problem

Functional human T-cell immunity and osteoprotegerin ligand control alveolar bone destruction in periodontal infection

Periodontitis, a prime cause of tooth loss in humans, is implicated in the increased risk of systemic diseases such as heart failure, stroke, and bacterial pneumonia. The mechanisms by which periodontitis and antibacterial immunity lead to alveolar bone and tooth loss are poorly understood. To study the human immune response to specific periodontal infections, rye transplanted human peripheral blood lymphocytes (HuPBLs) from periodontitis patients into NOD/SCID mice. Oral challenge of HuPBL-NOD/SCID mice with Actinobacillus actinomycetemcomitans, a well-known Gram-negative anaerobic microorganism that causes human periodontitis, activates human CD4(+) T cells in the periodontium and triggers local alveolar bone destruction. Human CD4(+) T cells, but not CD8(+) T cells or B cells, are identified as essential mediators of alveolar bone destruction. Stimulation of CD4(+) T cells by A. actinomycetemcomitans induces production of osteoprotegerin ligand (OPG-L), a key modulator of osteoclastogenesis and osteoclast activation. In vivo inhibition of OPG-L function with the decoy receptor OPG diminishes alveolar bone destruction and reduces the number of peridontal osteoclasts after microbial challenge. These data imply that the molecular explanation for alveolar bone destruction observed in perio dental infections is mediated by microorganism-triggered induction of OPG-L expression on CD4(+) T cells and the consequent activation of osteoclasts. Inhibition of OPG-L may thus have therapeutic value to prevent alveolar bone and/or tooth loss in human periodontitis.open11263sciescopu

Discrepancy in clinical outcomes of patients with gunshot wounds in car hijacking: a South African experience

INTRODUCTION: Discrepancy in outcomes between urban and rural trauma patients is well known. We reviewed our institutional experience with the management of gunshot wounds (GSWs) in the specific setting of car hijacking and focused on clinical outcome between rural and urban patients. METHODS: A retrospective review was conducted at a major trauma centre in South Africa over an 8-year period for all patients who presented with any form of GSWs in car hijacking settings. Specific clinical outcomes were compared between rural and urban patients. RESULTS: A total of 101 patients were included (74% male, mean age 34 years). Fifty-five per cent were injured in rural areas and the remaining 45% (45/101) were in the urban district. Mean time from injury to arrival at our trauma centre was 11 hours for rural and 4 hours for urban patients (p < 0.001). Seventy-six per cent (76/101) sustained GSWs to multiple body regions. Sixty-three of the 101 (62%) patients required one or more operative interventions. In individual logistic regressions adjusted for sex and number of regions injured, rural patients were 9 (95% CI: 1.9-44.4) and 7 (95% CI: 2.124.5) times more likely than urban patients to have morbidities or required admissions to intensive care respectively. The risk of death in rural patients was 36 (95% CI: 4.5-284.6) times higher than that of urban patients. CONCLUSIONS: Patients who sustained GSWs in carjacking incidents that occurred in rural areas are associated with significantly greater morbidity and mortality compared with their urban counterparts. Delay to definitive care is likely to be the significant contributory factor, and improvement in prehospital emergency medical service is likely to be beneficial in improving patient outcome

A review of blunt pelvic injuries at a major trauma centre in South Africa.

BACKGROUND: The collective five-year experience with the acute management of pelvic trauma at a busy South African trauma service is reviewed to compare the usefulness and applicability of current grading systems of pelvic trauma and to review the compliance with current guidelines regarding pelvic binder application during the acute phase of resuscitation. METHODS: A retrospective review was conducted over a 5-year period from December 2012 to December 2017 on all polytrauma patients who presented with a pelvic fracture. Mechanism of injury and presenting physiology and clinical course including pelvic binder application were documented. Pelvic fractures were graded according to the Young- Burgess and Tile systems. RESULTS: There was a cohort of 129 patients for analysis. Eighty-one were male and 48 female with a mean age was 33.6 ± 13.1 years. Motor vehicle-related collisions (MVCs) were the main mechanism of injury (50.33%) and pedestrian vehicle collisions (PVCs) were the second most common (37.98%). The most common associated injuries were abdominal injuries (41%), chest injury (37%), femur fractures (21%), tibia fractures (15%) and humerus fracture (14.7%). Thirty patients in this cohort (23%) underwent a laparotomy. They were mainly in the Tile B (70%) and lateral compression (63%) groups. Nine patients underwent pelvic pre-peritoneal packing. Thirty-five (27%) patients were admitted to ICU. Fifteen (12%) patients died. The Young-Burgess classification had a greater accuracy in predicting death than the Tile classification. Forty per cent of deaths occurred in ICU, 33% died secondary to a traumatic brain injury (TBI). Twenty per cent died in casualty and 6.6% in the operating room from ongoing haemorrhage. A pelvic binder was not applied in 66% of patients. In the 34% of patients who had a pelvic binder applied, it was applied post CT scan in 24.8%, in the pre-hospital setting in 7.2%, and on arrival in 2.4% of patients. In 73% of deaths, a binder was not applied, and of those deaths, 54% showed signs of haemodynamic instability. CONCLUSION: It would appear that our application of pelvic binders in patients with acute pelvic trauma is ad hoc. Appropriate selection of patients, who may benefit from a binder and it's timely application, has the potential to improve outcome in these patients

Privacy-Preserving Patient Similarity Learning in a Federated Environment: Development and Analysis

Background: There is an urgent need for the development of global analytic frameworks that can perform analyses in a privacy-preserving federated environment across multiple institutions without privacy leakage. A few studies on the topic of federated medical analysis have been conducted recently with the focus on several algorithms. However, none of them have solved similar patient matching, which is useful for applications such as cohort construction for cross-institution observational studies, disease surveillance, and clinical trials recruitment. Objective: The aim of this study was to present a privacy-preserving platform in a federated setting for patient similarity learning across institutions. Without sharing patient-level information, our model can find similar patients from one hospital to another. Methods: We proposed a federated patient hashing framework and developed a novel algorithm to learn context-specific hash codes to represent patients across institutions. The similarities between patients can be efficiently computed using the resulting hash codes of corresponding patients. To avoid security attack from reverse engineering on the model, we applied homomorphic encryption to patient similarity search in a federated setting. Results: We used sequential medical events extracted from the Multiparameter Intelligent Monitoring in Intensive Care-III database to evaluate the proposed algorithm in predicting the incidence of five diseases independently. Our algorithm achieved averaged area under the curves of 0.9154 and 0.8012 with balanced and imbalanced data, respectively, in ??-nearest neighbor with ??=3. We also confirmed privacy preservation in similarity search by using homomorphic encryption. Conclusions: The proposed algorithm can help search similar patients across institutions effectively to support federated data analysis in a privacy-preserving manner

Digestion of Raw and Roasted Almonds in Simulated Gastric Environment

Knowledge of digestion kinetics of solid foods in human stomach, as affected by food processing methods, is critical in establishing processing conditions at the manufacturing stage to achieve desirable release of nutrients in the gastrointestinal tract. The objective of this study was to investigate how roasting affected disintegration and solid release properties of almond in simulated gastric environment. In vitro trials were performed for raw and roasted almonds by using static soaking method and a model stomach system. The changes in sample weight, dry mass, and moisture during the trials were determined. Both compression and penetration tests were used to investigate the texture of almonds with a focus on the influence of absorption of gastric juice. Light microscopy and transmission electronic microscopy were used to study the change in microstructure of the raw and roasted almonds after simulated digestion. The results suggested that the slow disintegration rate and the high amount of swelling of the almonds in the stomach may contribute to their high satiety property. Roasting significantly improved the disintegration rates of almonds and increased loss of solids during simulated digestion, which is well correlated with the decrease in the rigidity of almond samples after absorbing gastric juice. Microstructure of digested almonds showed breakage and breach of cell walls due to acid hydrolysis. Intercellular and intracellular channels formed in almonds during roasting are important for penetration of gastric juice that may facilitate an effective digestion

Activating signal cointegrator 2 required for liver lipid metabolism mediated by liver X receptors in mice

Activating signal cointegrator 2 (ASC-2), a cancer-amplified transcriptional coactivator of nuclear receptors and many other transcription factors, contains two LXXLL-type nuclear receptor interaction domains. Interestingly, the second LXXLL motif is highly specific to the liver X receptors (LXRs). In cotransfection, DN2, an ASC-2 fragment encompassing this motif, exerts a potent dominant-negative effect on transactivation by LXRs, which is rescued by ectopic coexpression of the full-length ASC-2 but not by other LXXLL-type coactivators, such as SRC-1 and TRAP220. In contrast, DN2/m, in which the LXXLL motif is mutated to LXXAA to abolish the interactions with LXRs, is without any effect. Accordingly, expression of DN2, but not DN2/m, in transgenic mice results in phenotypes that are highly homologous to those previously observed with LXRalpha(-/-) mice, including a rapid accumulation of large amounts of cholesterol and down-regulation of the known lipid-metabolizing target genes of LXRalpha in the liver upon being fed a high-cholesterol diet. These results identify ASC-2 as a physiologically important transcriptional coactivator of LXRs and demonstrate its pivotal role in the liver lipid metabolism.open1136sciescopu

Principled Selection of Baseline Covariates to Account for Censoring in Randomized Trials with a Survival Endpoint

The analysis of randomized trials with time-to-event endpoints is nearly always plagued by the problem of censoring. As the censoring mechanism is usually unknown, analyses typically employ the assumption of non-informative censoring. While this assumption usually becomes more plausible as more baseline covariates are being adjusted for, such adjustment also raises concerns. Pre-specification of which covariates will be adjusted for (and how) is difficult, thus prompting the use of data-driven variable selection procedures, which may impede valid inferences to be drawn. The adjustment for covariates moreover adds concerns about model misspecification, and the fact that each change in adjustment set, also changes the censoring assumption and the treatment effect estimand. In this paper, we discuss these concerns and propose a simple variable selection strategy that aims to produce a valid test of the null in large samples. The proposal can be implemented using off-the-shelf software for (penalized) Cox regression, and is empirically found to work well in simulation studies and real data analyses

Rotational Mobility Analysis of the 3-RFR Class of Spherical Parallel Robots

none4noSpherical parallel manipulators (SPMs) are used to orient a tool in the space with three degrees of freedom exploiting the strengths of a multi-limb architecture. On the other hand, the performance of parallel kinematics machines (PKMs) is often affected by the occurrence of different kinds of singular configurations. The paper aims at characterizing a class of SPMs for which all singularities come to coincide and a single expression is able to describe all the singular configurations of the machines. The study is focused on a class of SPMs with 3-RFR topology (Revolute-Planar-Revolute pairs for each of the three limbs) addressing the mobility and singularity analysis by means of polynomial decomposition and screw theory. The neatness of the equations that are worked out, expressed in a robust formulation based on rotation invariants, allows a straightforward planning of singularity free tasks and simplifies the synthesis of dexterous machines.openCorinaldi, David; Carbonari, Luca; Palpacelli, Matteo-Claudio; Callegari, MassimoCorinaldi, David; Carbonari, Luca; Palpacelli, Matteo-Claudio; Callegari, Massim