Experimental evidence of antiproton reflection by a solid surface

We report here experimental evidence of the reflection of a large fraction of a beam of low energy antiprotons by an aluminum wall. This derives from the analysis of a set of annihilations of antiprotons that come to rest in rarefied helium gas after hitting the end wall of the apparatus. A Monte Carlo simulation of the antiproton path in aluminum indicates that the observed reflection occurs primarily via a multiple Rutherford-style scattering on Al nuclei, at least in the energy range 1-10 keV where the phenomenon is most visible in the analyzed data. These results contradict the common belief according to which the interactions between matter and antimatter are dominated by the reciprocally destructive phenomenon of annihilation.Comment: 5 pages with 5 figure

Sex differences in the association of psychological status with measures of physical activity and sedentary behaviour in adults with type 2 diabetes

Aim – To assess the association of psychological variables on leisure time physical activity and sedentary time in men and women with type 2 diabetes mellitus (T2D). Methods – In this cross-sectional study, we evaluated 163 patients with T2D, consecutively recruited at the Diabetes Centre of the Verona General Hospital. Scores on depression and anxiety symptoms, psychosocial factors (including self-efficacy, perceived interference, perceived severity, social support, misguided support behaviour, spouse’s positive behaviour), physical activity and time spent sitting were ascertained using questionnaires responses to the Beck Depression Inventory-II, Beck Anxiety Inventory, Multidimensional Diabetes Questionnaire, International Physical Activity Questionnaire. Results – Physical activity was significantly associated with higher social support in women, and with increased self-efficacy in men. Sedentary time was significantly associated with higher perceived interference, anxiety and depressive symptoms, and with reduced diabetes self-efficacy in women, while it was associated solely with anxiety in men. Depressive symptoms and self-efficacy in women and anxiety symptoms in men were independent predictors of sedentary time when entered in a multivariable regression model also including age, BMI, hemoglobin A1c, diabetes duration, perceived interference and self-efficacy as covariates. Conclusions – Lower self-efficacy and higher symptoms of depression were closely associated with increased sedentary time in women, but not in men, with T2D. It is possible that individualized behavioral interventions designed to reduce depressive symptoms and to improve diabetes self-efficacy would ultimately reduce sedentary behaviours, particularly in women with T2D

COVID-19 and MIS-C treatment in children—results from an international survey

Children have been mostly excluded from COVID-19 clinical trials, and, as a result, most medicines approved for COVID-19 have no pediatric indication. In addition, access to COVID-19 therapeutics remains limited. Collecting physicians’ experiences with off-label use of therapeutics is important to inform global prioritization processes and better target pediatric research and development. A standardized questionnaire was designed to explore the use of therapeutics used to treat COVID-19 and multisystem inflammatory syndrome in children (MIS-C) in pediatric patients globally. Seventy-three physicians from 29 countries participated. For COVID-19, steroids were used by 75.6% of respondents; remdesivir and monoclonal antibodies were prescribed by 48.6% and 27.1% of respondents, respectively. For MIS-C, steroids were prescribed by 79.1% of respondents and intravenous immunoglobulins by 69.6%. The use of these products depended on their pediatric approval and the limited availability of antivirals and most monoclonal antibodies in Africa, South America, Southeast Asia, and Eastern Europe. Off-label prescription resulted widespread due to the paucity of clinical trials in young children at the time of the survey; though, based on our survey results, it was generally safe and led to clinical benefits. Conclusion: This survey provides a snapshot of current practice for treating pediatric COVID-19 worldwide, informing global prioritization efforts to better target pediatric research and development for COVID-19 therapeutics. Off-label use of such medicines is widespread for the paucity of clinical trials under 12 years and 40 kg, though appears to be safe and generally results in clinical benefits, even in young children. However, access to care, including medicine availability, differs widely globally. Clinical development of COVID-19 antivirals and monoclonal antibodies requires acceleration to ensure pediatric indication and allow worldwide availability of therapeutics that will enable more equitable access to COVID-19 treatment. What is Known: • Children have been mostly excluded from COVID-19 clinical trials, and, as a result, most medicines approved for COVID-19 have no pediatric indication. • Access to care differs widely globally, so because of the diversity of national healthcare systems; the unequal availability of medicines for COVID-19 treatment represents an obstacle to the pediatric population's universal right to health care. What is New: • Off-label COVID-19 drug prescription is widespread due to the lack of clinical trials in children younger than 12 years and weighing less than 40 kg, but relatively safe and generally leading to clinical benefit. • The application of the GAP-f framework to COVID-19 medicines is crucial, ensuring widespread access to all safe and effective drugs, enabling the rapid development of age-appropriate formulations, and developing specific access plans (including stability, storage, packaging, and labeling) for distribution in low- and middle-income countries (LMICs). Antivirals and monoclonal antibodies may benefit from the acceleration to reach widespread and equal diffusion

Analysis of lower limb internal kinetics and electromyography in elite race walking.

The aim of this study was to analyse lower limb joint moments, powers and electromyography patterns in elite race walking. Twenty international male and female race walkers performed at their competitive pace in a laboratory setting. The collection of ground reaction forces (1000 Hz) was synchronised with two-dimensional high-speed videography (100 Hz) and electromyography of seven lower limb muscles (1000 Hz). As well as measuring key performance variables such as speed and stride length, normalised joint moments and powers were calculated. The rule in race walking which requires the knee to be extended from initial contact to midstance effectively made the knee redundant during stance with regard to energy generation. Instead, the leg functioned as a rigid lever which affected the role of the hip and ankle joints. The main contributors to energy generation were the hip extensors during late swing and early stance, and the ankle plantarflexors during late stance. The restricted functioning of the knee during stance meant that the importance of the swing leg in contributing to forward momentum was increased. The knee flexors underwent a phase of great energy absorption during the swing phase and this could increase the risk of injury to the hamstring muscles

DNA profiling, telomere analysis and antioxidant properties as tools for monitoring ex situ seed longevity

Background and Aims The germination test currently represents the most used method to assess seed viability in germplasm banks, despite the difficulties caused by the occurrence of seed dormancy. Furthermore, seed longevity can vary considerably across species and populations from different environments and studies related to the eco-physiological processes underlying such variations are still limited in their depth. The aim of the present work was the identification of reliable molecular markers that might help monitoring seed deterioration. Methods Dry seeds were subjected to artificial aging and collected at different time points for molecular/biochemical analyses. DNA damage was measured using the RAPD (Random Amplified Polymorphic DNA) approach while the seed antioxidant profile was obtained using both the DPPH (1,1-diphenyl, 2-picrylhydrazyl) assay and the Folin Ciocalteu reagent method. Electron Paramagnetic Resonance (EPR) provided profiles of free radicals. Quantitative RealTime-Polymerase Chain Reaction (QRT-PCR) was used to assess the expression profiles of the antioxidant genes MT2 (Type 2 Metallothionein) and SOD (Superoxide Dismutase). A modified QRT-PCR protocol was used to determine telomere length. Key Results The RAPD profiles highlighted different capacities of the two Silene species to overcome DNA damage induced by artificial aging. The antioxidant profiles of dry and rehydrated seeds revealed that the high-altitude taxon Silene acaulis was characterised by a lower antioxidant specific activity. Significant up-regulation of the MT2 and SOD genes was observed only in the rehydrated seeds of the low-altitude species. Rehydration resulted in telomere lengthening in both Silene species. Conclusions Different seed viability markers have been selected for plant species showing inherent variation of seed longevity. RAPD analysis, quantification of redox activity of non enzymatic antioxidant compounds and gene expression profiling provide deeper insights to study seed viability during storage. Telomere lengthening is a promising tool to discriminate between short- and long-lived species

FoxO3a as a positive prognostic marker and a therapeutic target in Tamoxifen-resistant breast cancer

Background: Resistance to endocrine treatments is a major clinical challenge in the management of estrogen receptor positive breast cancers. Although multiple mechanisms leading to endocrine resistance have been proposed, the poor outcome of this subgroup of patients demands additional studies. Methods: FoxO3a involvement in the acquisition and reversion of tamoxifen resistance was assessed in vitro in three parental ER+ breast cancer cells, MCF-7, T47D and ZR-75-1, in the deriving Tamoxifen resistant models (TamR) and in Tet-inducible TamR/FoxO3a stable cell lines, by growth curves, PLA, siRNA, RT-PCR, Western blot, Immunofluorescence, Transmission Electron Microscopy, TUNEL, cell cycle, proteomics analyses and animal models. FoxO3a clinical relevance was validated in silico by Kaplan−Meier survival curves. Results: Here, we show that tamoxifen resistant breast cancer cells (TamR) express low FoxO3a levels. The hyperactive growth factors signaling, characterizing these cells, leads to FoxO3a hyper-phosphorylation and subsequent proteasomal degradation. FoxO3a re-expression by using TamR tetracycline inducible cells or by treating TamR with the anticonvulsant lamotrigine (LTG), restored the sensitivity to the antiestrogen and strongly reduced tumor mass in TamR-derived mouse xenografts. Proteomics data unveiled novel potential mediators of FoxO3a anti-proliferative and pro-apoptotic activity, while the Kaplan−Meier analysis showed that FoxO3a is predictive of a positive response to tamoxifen therapy in Luminal A breast cancer patients. Conclusions: Altogether, our data indicate that FoxO3a is a key target to be exploited in endocrine-resistant tumors. In this context, LTG, being able to induce FoxO3a, might represent a valid candidate in combination therapy to prevent resistance to tamoxifen in patients at risk

Microbial ecology of coral-dominated reefs in the Federated States of Micronesia

© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Apprill, A., Holm, H., Santoro, A. E., Becker, C., Neave, M., Hughen, K., Richards Dona, A., Aeby, G., Work, T., Weber, L., & McNally, S. Microbial ecology of coral-dominated reefs in the Federated States of Micronesia. Aquatic Microbial Ecology, 86, (2021): 115–136, https://doi.org/10.3354/ame01961.Microorganisms are central to the functioning of coral reef ecosystems, but their dynamics are unstudied on most reefs. We examined the microbial ecology of shallow reefs within the Federated States of Micronesia. We surveyed 20 reefs surrounding 7 islands and atolls (Yap, Woleai, Olimarao, Kosrae, Kapingamarangi, Nukuoro, and Pohnpei), spanning 875053 km2. On the reefs, we found consistently higher coral coverage (mean ± SD = 36.9 ± 22.2%; max 77%) compared to macroalgae coverage (15.2 ± 15.5%; max 58%), and low abundances of fish. Reef waters had low inorganic nutrient concentrations and were dominated by Synechococcus, Prochlorococcus, and SAR11 bacteria. The richness of bacterial and archaeal communities was significantly related to interactions between island/atoll and depth. High coral coverage on reefs was linked to higher relative abundances of Flavobacteriaceae, Leisingera, Owenweeksia, Vibrio, and the OM27 clade, as well as other heterotrophic bacterial groups, consistent with communities residing in waters near corals and within coral mucus. Microbial community structure at reef depth was significantly correlated with geographic distance, suggesting that island biogeography influences reef microbial communities. Reefs at Kosrae Island, which hosted the highest coral abundance and diversity, were unique compared to other locations; seawater from Kosrae reefs had the lowest organic carbon (59.8-67.9 µM), highest organic nitrogen (4.5-5.3 µM), and harbored consistent microbial communities (>85% similar), which were dominated by heterotrophic cells. This study suggests that the reef-water microbial ecology on Micronesian reefs is influenced by the density and diversity of corals as well as other biogeographical features.Samples were collected under Federated States of Micronesia collection permits FM12-11-03S and FM12-11-05S. This project was supported by funding to A.A.: Woods Hole Oceanographic Institution Access to the Sea, Dalio Family Foundation, Andrew W. Mellon Foundation Endowed Fund for Innovative Research, and National Science Foundation awards OCE- 1233612 and OCE-1736288. A.E.S. was supported by startup funds from the University of Maryland Center for Environmental Sciences. K.H. obtained funding from WHOI Access to the Sea and the Dalio Explore Foundation that supported this cruise

Correlated Λd\Lambda d pairs from the Kstop−A→ΛdA′K^{-}_{stop} A \to \Lambda d A' reaction

Correlated $\Lambda d$ pairs emitted after the absorption of negative kaons at rest $K^{-}_{stop}A\to \Lambda d A'$ in light nuclei $^6Li$ and $^{12}C$ are studied. $\Lambda$-hyperons and deuterons are found to be preferentially emitted in opposite directions. The $\Lambda d$ invariant mass spectrum of $^6Li$ shows a bump whose mass is 3251$\pm$6 MeV/c$^2$. The bump mass (binding energy), width and yield are reported. The appearance of a bump is discussed in the realm of the [$\bar{K}3N$] clustering process in nuclei. The experiment was performed with the FINUDA spectrometer at DA$\Phi$NE (LNF).Comment: 13 pages, 5 figures, accepted for publication in Phys. Lett.

A new look at loop quantum gravity

I describe a possible perspective on the current state of loop quantum gravity, at the light of the developments of the last years. I point out that a theory is now available, having a well-defined background-independent kinematics and a dynamics allowing transition amplitudes to be computed explicitly in different regimes. I underline the fact that the dynamics can be given in terms of a simple vertex function, largely determined by locality, diffeomorphism invariance and local Lorentz invariance. I emphasize the importance of approximations. I list open problems.Comment: 15 pages, 5 figure