We search for transient variations of the fine structure constant using data from a European network of fiber-linked optical atomic clocks. By searching for coherent variations in the recorded clock ...frequency comparisons across the network, we significantly improve the constraints on transient variations of the fine structure constant. For example, we constrain the variation to |δα/α| < 5 × 10−17 for transients of duration 103 s. This analysis also presents a possibility to search for dark matter, the mysterious substance hypothesised to explain galaxy dynamics and other astrophysical phenomena that is thought to dominate the matter density of the universe. At the current sensitivity level, we find no evidence for dark matter in the form of topological defects (or, more generally, any macroscopic objects), and we thus place constraints on certain potential couplings between the dark matter and standard model particles, substantially improving upon the existing constraints, particularly for large (≳104 km) objects.
ABSTRACT
We present the S-PLUS Transient Extension Program (STEP): a supernova and fast transient survey conducted in the southern hemisphere using data from the Southern Photometric Local Universe ...Survey (S-PLUS) Main Survey and the T80-South telescope. Transient astrophysical phenomena have a range of interest that goes through different fields of astrophysics and cosmology. With the detection of an electromagnetic counterpart to the gravitational wave (GW) event GW170817 from a binary neutron stars merger, new techniques and resources to study fast astrophysical transients in the multimessenger context have increased. In this paper, we present the STEP overview, the SN follow-up data obtained, data reduction, analysis of new transients and deep learning algorithms to optimize transient candidate selection. Additionally, we present prospects and optimized strategy for the search of gravitational wave counterparts in the current LIGO/Virgo/Kagra observational run (O4) in the context of T80-South telescope.
The occurrence of fretting-induced cracks and delamination wear processes in a mixed fretting regime on Alloy 690 steam generator tubes against 304L stainless steel pads was analyzed. Fretting tests ...in 90° cross-cylinder configuration were performed in air at room temperature. Changes in the contact conditions were evaluated using the energy ratio and the sliding ratio criteria. Damage was characterized using light microscopy, scanning electron microscopy, and optical profilometry. Vickers microindentation was applied to characterize the initial plastic deformation process. It was found that during the initial 1 × 103 cycles, plastic deformation constitutes the main damage mechanism. Thereafter, between 1 × 103 and 1 × 104 cycles, cracks nucleation and propagation accompanied by negligible wear were detected. Beyond 1 × 104 cycles, the dominant main damage mechanism consists of delamination wear assisted by cracks coalescence, and a change from a U-shaped to a W-shaped scar profile was observed in correspondence with the appearance of the delamination wear process.
Introduction
After endoscopic resection (ER) of neoplasia in Barrett’s esophagus (BE), it is recommended to ablate the remaining BE to minimize the risk for metachronous disease. However, we report ...long-term outcomes for a nationwide cohort of all patients who did not undergo ablation of the remaining BE after ER for early BE neoplasia, due to clinical reasons or performance status.
Methods
Endoscopic therapy for BE neoplasia in the Netherlands is centralized in 8 expert centers with specifically trained endoscopists and pathologists. Uniformity is ensured by a joint protocol and regular group meetings. We report all patients who underwent ER for a neoplastic lesion between 2008 and 2018, without further ablation therapy. Outcomes include progression during endoscopic FU and all-cause mortality.
Results
Ninety-four patients were included with mean age 74 (± 10) years. ER was performed for low-grade dysplasia (LGD) (10%), high-grade dysplasia (HGD) (25%), or low-risk esophageal adenocarcinoma (EAC) (65%). No additional ablation was performed for several reasons; in 73 patients (78%), the main argument was expected limited life expectancy. Median C2M5 BE persisted after ER, and during median 21 months (IQR 11–51) with 4 endoscopies per patient, no patient progressed to advanced cancer. Seventeen patients (18%) developed HGD/EAC: all were curatively treated endoscopically. In total, 29/73 patients (40%) with expected limited life expectancy died due to unrelated causes during FU, none of EAC.
Conclusion
In selected patients, ER monotherapy with endoscopic surveillance of the residual BE is a valid alternative to eradication therapy with ablation.
Antimicrobial resistance (AMR) represents a major challenge for Public Health and the scientific community, and requires immediate and drastic solutions. Acquired resistance to certain antimicrobials ...is already widespread to such an extent that their efficacy in the treatment of certain life‐threatening infections is already compromised. To date, the emergence and spread of AMR has been attributed to the use, misuse or indiscriminate use of antibiotics as therapeutic drugs in human, animal and plant health, or as growth promoters in veterinary husbandry. In addition, there is growing concern over the possibility of AMR transmission via the food chain. Food processing environments could act as potential hotspots for AMR acquisition and spread. Indeed, biocide use and exposure to food‐related stresses and food processing technologies could presumably act as selection pressures for increased microbial resistance against clinically relevant antibiotics. Global AMR surveillance is critical for providing the necessary information to form global strategies and to monitor the effectiveness of public health interventions as well as to detect new trends and emerging threats. Surveillance of AMR is currently based on the isolation of indicator microorganisms and the phenotypic characterisation of the strains isolated. However, this approach provides very limited information on the mechanisms driving AMR or on the presence and spread of AMR genes. Whole genome sequencing (WGS) of bacterial pathogens is a powerful tool that can be used for epidemiological surveillance, outbreak detection and infection control. In addition, whole metagenome sequencing (WMS) allows for the culture‐independent analysis of complex microbial communities, providing useful information on the occurrence of AMR genes. Both approaches can be used to provide the information necessary for the implementation of quantitative risk assessment of AMR transmission routes along the food chain.
The behavior of amphiphilic molecules such as lipids, peptides and their mixtures at the air/water interface allow us to evaluate and visualize the arrangement formed in a confined and controlled ...surface area. We have studied the surface properties of the zwitterionic DPPC lipid and Aβ(1–40) amyloid peptide in mixed films at different temperatures (from 15 to 40 °C). In this range of temperature the surface properties of pure Aβ(1–40) peptide remained unchanged, whereas DPPC undergoes its characteristic liquid-expanded → liquid-condensed bidimensional phase transition that depends on the temperature and lateral pressure. This particular property of DPPC makes it possible to dynamically study the influence of the lipid phase state on amyloid structure formation at the interface in a continuous, isothermal and abrupt change on the environmental condition. As the mixed film is compressed the fibril-like structure of Aβ(1–40) is triggered specifically in the liquid-expanded region, independently of temperature, and it is selectively excluded from the well-visible liquid condensed domains of DPPC. The Aβ amyloid fibers were visualized by using BAM and AFM and they were Thio T positive. In mixed DPPC/Aβ(1–40) films the condensed domains (in between 11 mN/m to 20 mN/m) become irregular probably due to the fibril-like structures is imposing additional lateral stress sequestering lipid molecules in the surrounding liquid-expanded phase to self-organize into amyloids.
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•Βeta amyloid peptide forms fibril-like structures in phospholipid liquid phase.•Lipid phase acts as an amyloid inductor in biomembranes.•Fibril-like structures can be triggered by the interfacial condition.
BACKGROUND: Screening for active TB using active case-finding (ACF) may reduce TB incidence, prevalence, and mortality; however, yield of ACF interventions varies substantially across populations. We ...systematically reviewed studies reporting on ACF to calculate the number needed
to screen (NNS) for groups at high risk for TB.METHODS: We conducted a literature search for studies reporting ACF for adults published between November 2010 and February 2020. We determined active TB prevalence detected through various screening strategies and calculated crude
NNS for - TB confirmed using culture or Xpert® MTB/RIF, and weighted mean NNS stratified by screening strategy, risk group, and country-level TB incidence.RESULTS: We screened 27,223 abstracts; 90 studies were included (41 in low/moderate and 49 in medium/high TB
incidence settings). High-risk groups included inpatients, outpatients, people living with diabetes (PLWD), migrants, prison inmates, persons experiencing homelessness (PEH), healthcare workers, and miners. Screening strategies included symptom-based screening, chest X-ray and Xpert testing.
NNS varied widely across and within incidence settings based on risk groups and screening methods. Screening tools with higher sensitivity (e.g., Xpert, CXR) were associated with lower NNS estimates.CONCLUSIONS: NNS for ACF strategies varies substantially between adult risk groups.
Specific interventions should be tailored based on local epidemiology and costs.
To investigate the impact of hip osteoarthritis (OA) and/or hip symptoms on excess mortality.
We analyzed data from 3,919 individuals in a community-based prospective cohort of African Americans and ...Caucasians age ≥45 years. Women ≥50 years of age and all men underwent supine anteroposterior pelvic radiography at baseline, with the participant's feet in 15 degrees of internal rotation. Hip radiographic (rOA) was defined as a Kellgren–Lawrence grade of ≥2 in at least one hip. Participants completed questionnaires at baseline to determine presence of hip symptoms and covariate status. Participants with symptomatic hip rOA (SxOA) are a subset of individuals with hip rOA and symptoms in the same hip. Multiple imputation was used to impute missing values of covariates. Mortality was determined through 2015 and follow-up time was calculated from baseline assessment until death or censoring which took place when a participant was lost to follow-up or reached the end of study period. Cox proportional hazards regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI). We carried out additional analyses stratified by sex, race, age and obesity.
Mean follow-up time was 14.2 years during which 1762 deaths occurred. There were 29.9% participants in our population with hip rOA at baseline. Compared to those with neither hip rOA nor hip symptoms, we observed an increased risk of all-cause mortality in participants with hip symptoms alone (HR = 1.28, 95% CI = 1.13–1.46), but no association for hip rOA either with or without symptoms. In stratified analyses we observed increased associations for hip symptoms alone and hip sxOA in those <65 years (43% and 39% increase, respectively) and in Caucasians (34% and 21% increase, respectively).
Individuals who had hip symptoms without hip rOA had an increased risk of mortality. These effects were particularly strong for those who were <65 years of age and Caucasians. Effective interventions to identify those with hip pain in order to lessen it could reduce premature mortality.
Background
Providing patients with access to health information that can be obtained outside of an office visit is an important part of education, yet little is known about the effectiveness of ...outreach modalities to connect older adults to online educational tools. The objective was to identify the effectiveness and cost of outreach modalities providing online information about advance care planning (ACP) for older adults.
Methods
Six different outreach modalities were utilized to connect patients to online educational tools (ACP video decision aids). Participants were 13,582 patients aged 65 and older of 185 primary care providers with appointments over a 30-month period within a large health system in the greater New York City area. Main outcome measures were number of online video views and costs per outreach for each modality.
Key Results
There were 1150 video views for 21,407 remote outreach events. Text messages, sent to the largest volume of patients (8869), had the highest outcome rate (9.6%) and were the most economical ($0.09). Characterization of phone calls demonstrated 21.7% engagement in the topic of ACP but resulted in minimal video views (<1%) and incurred the highest cost per outreach ($2.88). In-office handouts had negligible results (<1%).
Conclusions
Text was the most cost-effective modality to connect older adults to an online educational tool in this pragmatic trial, though overall efficacy of all modalities was low.
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