Ultraperipheral collisions (UPCs) of heavy ions and protons are the energy frontier for electromagnetic interactions. Both photonuclear and two-photon collisions are studied at collision energies ...that are far higher than those available elsewhere. In this review, we discuss physics topics that can be addressed with UPCs, including nuclear shadowing, nuclear structure, and searches for physics beyond the Standard Model.
Immune responses need to be controlled for optimal protective immunity and tolerance. Coinhibitory pathways in the B7-CD28 family provide critical inhibitory signals that regulate immune homeostasis ...and defense and protect tissue integrity. These coinhibitory signals limit the strength and duration of immune responses, thereby curbing immune-mediated tissue damage, regulating resolution of inflammation, and maintaining tolerance to prevent autoimmunity. Tumors and microbes that cause chronic infections can exploit these coinhibitory pathways to establish an immunosuppressive microenvironment, hindering their eradication. Advances in understanding T cell coinhibitory pathways have stimulated a new era of immunotherapy with effective drugs to treat cancer, autoimmune and infectious diseases, and transplant rejection. In this review we discuss the current knowledge of the mechanisms underlying the coinhibitory functions of pathways in the B7-CD28 family, the diverse functional consequences of these inhibitory signals on immune responses, and the overlapping and unique functions of these key immunoregulatory pathways.
Coinhibitory pathways in the B7-CD28 family provide critical inhibitory signals that regulate immune homeostasis and defense. Sharpe and colleagues discuss the current understanding of mechanisms underlying the coinhibitory functions of pathways in the B7-CD28 family, their functional consequences, and their overlapping and unique functions.
In this paper we present an automatic algorithm to detect basic shapes in unorganized point clouds. The algorithm decomposes the point cloud into a concise, hybrid structure of inherent shapes and a ...set of remaining points. Each detected shape serves as a proxy for a set of corresponding points. Our method is based on random sampling and detects planes, spheres, cylinders, cones and tori. For models with surfaces composed of these basic shapes only, for example, CAD models, we automatically obtain a representation solely consisting of shape proxies. We demonstrate that the algorithm is robust even in the presence of many outliers and a high degree of noise. The proposed method scales well with respect to the size of the input point cloud and the number and size of the shapes within the data. Even point sets with several millions of samples are robustly decomposed within less than a minute. Moreover, the algorithm is conceptually simple and easy to implement. Application areas include measurement of physical parameters, scan registration, surface compression, hybrid rendering, shape classification, meshing, simplification, approximation and reverse engineering.
The private sector’s role in climate finance is increasingly subject to political and scientific debate. Yet there is poor empirical evidence of private engagement in adaptation and its potential ...contribution to the industrialised countries’ mobilisation of USD 100 billion of annual climate finance from 2020 onwards to support developing countries to address climate change. This paper analysed 101 case studies of private sector adaptation under the Private Sector Initiative (PSI) of the UNFCCC Nairobi work programme, and examined these against ten ‘adaptation finance criteria’ that were distilled from UN climate negotiation outcomes. Results show that private adaptation interventions complement public adaptation activities. Yet the ten adaptation finance criteria are not met, which demonstrates that the diplomatic UNFCCC conceptualisation of financing adaptation is dissonant from the private sector reality. For example, while the case studies’ investments are ‘new and additional’ to Official Development Assistance (ODA), their ‘predictability’ remains unclear. And despite some commitment for ‘up-scaling’, plans and associated costs for doing so remain undisclosed. Developed countries’ role in ‘mobilising’ private financial resources under the PSI seems limited. It is unrealistic to expect that the UNFCCC alters existing criteria to suit private initiatives, or that the private sector aligns its initiatives to meet existing criteria. This paper advocates monitoring and reporting only of those private investments that principally finance adaptation. This practical way forward would allow private finance to meet criteria such as predictability, transparency, and mobilisation, but would drastically reduce the amount of private investment that could contribute to reaching the USD 100 billion climate finance target.
Following the recent isolation of monolayer CrI3 (ref. 1), many more two-dimensional van der Waals magnetic materials have been isolated2–12. Their incorporation in van der Waals heterostructures ...offers a new platform for spintronics5–9, proximity magnetism13 and quantum spin liquids14. A primary question in this field is how exfoliating crystals to the few-layer limit influences their magnetism. Studies of CrI3 have shown a different magnetic ground state for ultrathin exfoliated films1,5,6 compared with the bulk, but the origin is not yet understood. Here, we use electron tunnelling through few-layer crystals of the layered antiferromagnetic insulator CrCl3 to probe its magnetic order and find a tenfold enhancement of the interlayer exchange compared with bulk crystals. Moreover, temperature- and polarization-dependent Raman spectroscopy reveals that the crystallographic phase transition of bulk crystals does not occur in exfoliated films. This results in a different low-temperature stacking order and, we hypothesize, increased interlayer exchange. Our study provides insight into the connection between stacking order and interlayer interactions in two-dimensional magnets, which may be relevant for correlating stacking faults and mechanical deformations with the magnetic ground states of other more exotic layered magnets such as RuCl3 (ref. 14).
Advances in mass spectrometry have made it a preferred tool for structural characterization of glycerophospholipids. Collisional activation methods commonly implemented on commercial instruments do ...not provide fragmentation patterns that allow elucidation of certain structural features, including acyl chain positions on the glycerol backbone and double bond positions within acyl chains. In the present work, 193 nm ultraviolet photodissociation (UVPD) implemented on an Orbitrap mass spectrometer is used to localize double bond positions within phosphatidylcholine (PC) acyl chains. Cleavage of the carbon–carbon bonds adjacent to the double bond provides a diagnostic mass difference of 24 Da and enables differentiation of double-bond positional isomers. The UVPD method was extended to the characterization of PCs in a bovine liver extract via a shotgun strategy. Positive mode higher energy collisional dissociation (HCD) and UVPD, and negative mode HCD were undertaken in a complementary manner to identify species as PCs and to localize double bonds, respectively.
Endoscopic prediction of polyp histology is rapidly improving to the point where it may not be necessary to submit all polyps for formal histologic assessment. This study aimed to quantify the ...expected costs and outcomes of removing diminutive polyps without subsequent pathologic assessment.
Cross-sectional analysis of a colonoscopy database for polyp histology; decision models that quantify effects on guideline-recommended surveillance and subsequent costs and consequences. The database was composed of consecutive colonoscopies from 1999 to 2004 at a single-institution tertiary care center. Patients were those found to have at least one diminutive polyp removed during colonoscopy, irrespective of indication. The main outcome measurements include up-front cost savings resulting from forgoing pathologic assessment; frequency and cost of incorrect surveillance intervals based on errors in histologic assessment; number needed to harm (NNH) for perforation and/or interval cancer.
Incorrect surveillance intervals were recommended in 1.9% of cases when tissue was submitted for pathologic assessment and 11.8% of cases when it was not. Based on the annual volume of colonoscopy in the US, the annual up-front cost savings of forgoing the pathologic assessment would exceed a billion dollars. An upper estimate on the downstream costs and consequences of forgoing pathology suggests that less than 10% of the up-front savings would be offset and the NNH exceeds 11000.
Endoscopic diagnosis of polyp histology during colonoscopy and forgoing pathologic examination would result in substantial up-front cost savings. Downstream consequences of the resulting incorrect surveillance intervals appear to be negligible.
Purpose
We report a case in which the use of semaglutide for weight loss was associated with delayed gastric emptying and intraoperative pulmonary aspiration of gastric contents.
Clinical features
A ...42-yr-old patient with Barrett’s esophagus underwent repeat upper gastrointestinal endoscopy and ablation of dysplastic mucosa. Two months earlier, the patient had started weekly injections of semaglutide for weight loss. Despite having fasted for 18 hr, and differing from the findings of prior procedures, endoscopy revealed substantial gastric content, which was suctioned before endotracheal intubation. Food remains were removed from the trachea and bronchi using bronchoscopy. The patient was extubated four hours later and remained asymptomatic.
Conclusion
Patients using semaglutide and other glucagon-like peptide 1 agonists for weight management may require specific precautions during induction of anesthesia to prevent pulmonary aspiration of gastric contents.
Higher plants exhibit remarkable phenotypic plasticity allowing them to adapt to an extensive range of environmental conditions. Sorghum is a cereal crop that exhibits exceptional tolerance to ...adverse conditions, in particular, water-limiting environments. This study utilized next generation sequencing (NGS) technology to examine the transcriptome of sorghum plants challenged with osmotic stress and exogenous abscisic acid (ABA) in order to elucidate genes and gene networks that contribute to sorghum's tolerance to water-limiting environments with a long-term aim of developing strategies to improve plant productivity under drought.
RNA-Seq results revealed transcriptional activity of 28,335 unique genes from sorghum root and shoot tissues subjected to polyethylene glycol (PEG)-induced osmotic stress or exogenous ABA. Differential gene expression analyses in response to osmotic stress and ABA revealed a strong interplay among various metabolic pathways including abscisic acid and 13-lipoxygenase, salicylic acid, jasmonic acid, and plant defense pathways. Transcription factor analysis indicated that groups of genes may be co-regulated by similar regulatory sequences to which the expressed transcription factors bind. We successfully exploited the data presented here in conjunction with published transcriptome analyses for rice, maize, and Arabidopsis to discover more than 50 differentially expressed, drought-responsive gene orthologs for which no function had been previously ascribed.
The present study provides an initial assemblage of sorghum genes and gene networks regulated by osmotic stress and hormonal treatment. We are providing an RNA-Seq data set and an initial collection of transcription factors, which offer a preliminary look into the cascade of global gene expression patterns that arise in a drought tolerant crop subjected to abiotic stress. These resources will allow scientists to query gene expression and functional annotation in response to drought.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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