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Ag-carbon composite interlayers have been reported to enable Li-free (anodeless) cycling of solid-state batteries. Here, we report structural changes in the Ag-graphite interlayer, showing that on charge, Li intercalates electrochemically into graphite, subsequently reacting chemically with Ag to form Li-Ag alloys. Discharge is not the reverse of charge but rather passes through Li-deficient Li-Ag phases. At higher charging rates, Li intercalation into graphite outpaces the chemical reactions with Ag, delaying the formation of the Li-Ag phases and resulting in more Li metal deposition at the current collector. At and above 2.5 mA·cm−2, Li dendrites are not suppressed. Ag nanoparticles do not suppress dendrites more effectively than does an interlayer of graphite alone. Instead, Ag in the carbon interlayer results in more homogeneous Li and Li-Ag formation on the current collector during charge.

ETSI ISG Non-IP Networking (NIN) was formed to standardize Flexilink, a networking technology which does not have the problems mobile operators had identified with current technology based on Internet Protocol (IP). This paper reviews the main features of Flexilink and the advantages of the services it provides for future network applications beyond 2030. Internet Protocol is connection-less, so every packet has to carry all the information needed to route it to its destination and this information has to be processed by each router the packet passes through. However, in most cases it is used to carry a "flow" of packets for a connection-oriented protocol such as TCP or RTP. Routing in SDN applies to flows rather than individual packets, but each packet header still contains the same routing information and must be processed to identify the flow to which the packet belongs. Flexilink replaces the per-flow information in the packet header with a pointer into the routing table, which eliminates the need for software processing of packet headers and means that packet formats are not dependent on the addressing scheme used. It also provides a separate service for live media such as audio, video, and tactile that easily achieves the lowest possible latency.

The Unified Modeling Language (UML) is considered the de facto standard for object-oriented software model development. This makes it appropriate to be used in academia courses at both the graduate and undergraduate levels of education. Some challenges to using the UML is academia are its large number of model concepts and the imprecise semantic of some of these concepts. These challenges are daunting for students who are being introduced to the UML. One approach that can be taken in teaching UML towards addressing these concerns is to limit the number of UML concepts taught and recognize that students may not be able to develop correct UML system models. This approach leads to research work that develop a limited set of UML model concepts that are fewer in number and have more precise semantics. In this paper, we present a new approach to resolve an aspect of this problem by simplifying the generalization/specialization semantics of the class diagram through the application of mathematical formality to usage of these class diagram concepts. Along with that, we discuss the progress of research in the area of verification of UML class models. This research work derives a core set of concepts suitable for graduate and undergraduate comprehension of UML modeling and defines more precise semantics for those modeling concepts. The applicable mathematical principles applied in this work are from the domains of set theory and predicate logic. This approach is particularly relevant for the pedagogy of software engineering and the development of software systems that require a high level of reliability.

BackgroundLassa fever (LF) is a rodent-borne disease endemic to West Africa. In the absence of licensed therapeutics or vaccines, rodent exclusion from living spaces remains the primary method of preventing LF. Zoonotic surveillance of Lassa virus (LASV), the etiologic agent of LF, can assess the burden of LASV in a region and guide public health measures against LF.MethodsIn this study, we adapted commercially available LASV human diagnostics to assess the prevalence of LASV in peri-domestic rodents in Eastern Sierra Leone. Small mammal trapping was conducted in Kenema district, Sierra Leone between November 2018-July 2019. LASV antigen was detected using a commercially available LASV NP antigen rapid diagnostic test. LASV IgG antibodies against LASV nucleoprotein (NP) and glycoprotein (GP) were tested by adapting a commercially available semi-quantitative enzyme linked immunosorbent assay (ELISA) for detection of mouse-related and rat-related species IgG.FindingsOf the 373 tested specimens, 74 (20%) tested positive for LASV antigen. 40 (11%) specimens tested positive for LASV NP IgG, while an additional 12 (3%) specimens only tested positive for LASV GP IgG. Simultaneous antigen presence and IgG antibody presence was linked inMastomys sp. specimens (p< 0.01), but notRattus sp. specimens (p= 1). Despite the link between antigen presence and IgG antibody presence inMastomys sp., the strength of antigen response did not correlate with the strength of IgG response to either GP IgG or NP IgG.InterpretationThe tools developed in this study can aid in the generation of valuable public health data for rapid field assessment of LASV burden during outbreak investigations and general LASV surveillance.FundingFunding for this work was supported by the National Institute of Allergy and Infectious Diseases National Institute of Health, Department of Health and Human Services under the following grants: International Collaboration in Infectious Disease Research on Lassa fever and Ebola - ICIDR - U19 AI115589, Consortium for Viral Systems Biology - CViSB - 5U19AI135995, West African Emerging Infectious Disease Research Center - WARN-ID - U01AI151812, West African Center for Emerging Infectious Diseases: U01AI151801.

Objectives To identify classes of heart failure (HF) caregivers based upon indicators of coping resources and stress, and then, to examine the relationships between the identified caregiver classes and depression, caregiver burden, and life changes. Methods Cross-sectional data from 530 HF caregivers were analyzed in this secondary analysis using a three-step latent class mixture model to classify caregivers based on level of resources and examine the relationship between the identified classes and depression, caregiver burden, and life changes. Using an online survey, caregivers reported on social support, problem-solving, family function, depression, caregiver burden, and life changes. Results Caregivers were 41.39 (± 10.38) years of age, 49.1% women, 78.3% white, 77.6% urban-dwelling, and 61.7% college/postgraduate educated. Three classes of caregivers (42.3% Adequately Resourced, 25.1% At Risk for Decompensation, 32.6% Inadequately Resourced) were identified. Inadequately Resourced caregivers had the lowest levels of social support, problem-solving, and family function and the highest levels of depression and caregiver burden. Caregivers At Risk for Decompensation had the best family function and reported the most positive perceptions of life changes despite low levels of social support and problem-solving. Conclusion Social support, problem-solving, and family function are modifiable coping resources which may buffer stress and influence stress indicators. Caregivers with few coping resources may experience higher degrees of depression and burden, and less positive perceptions of life changes. More research is needed to examine the influence of these coping resources on caregiver adaptation to facilitate the development of targeted interventions which support caregiver mental health.

Background Lower respiratory tract infections are the leading cause of mortality in young children globally. In many resource-limited settings clinicians rely on guidelines such as IMCI or ETAT + that promote empiric antibiotic utilization for management of acute respiratory illness (ARI). Numerous evaluations of both guidelines have shown an overall positive response however, several challenges have also been reported, including the potential for over prescribing of unnecessary antibiotics. Methods We conducted a prospective study of children

Carbon is an essential element for life but how much can be delivered to young planets is still an open question. The chemical characterization of planet-forming disks is a crucial step in our understanding of the diversity and habitability of exoplanets. Very low-mass stars ($, version submitted to Nature Astronomy

Background Cognitive dysfunction after surgery is a major issue in older adults. Here, we determined the effect of APOE4 on perioperative neurocognitive function in older patients. Methods We enrolled 140 English-speaking patients ≥60 yr old scheduled for noncardiac surgery under general anaesthesia in an observational cohort study, of whom 52 underwent neuroimaging. We measured cognition; Aβ, tau, p-tau levels in CSF; and resting-state intrinsic functional connectivity in six Alzheimer's disease-risk regions before and 6 weeks after surgery. Results There were no significant APOE4-related differences in cognition or CSF biomarkers, except APOE4 carriers had lower CSF Aβ levels than non-carriers (preoperative median CSF Aβ [median absolute deviation], APOE4 305 pg ml−1 [65] vs 378 pg ml−1 [38], respectively; P=0.001). Controlling for age, APOE4 carriers had significantly greater preoperative functional connectivity than non-carriers between several brain regions implicated in Alzheimer's disease, including between the left posterior cingulate cortex and left angular gyrus (β [95% confidence interval, CI], 0.218 [0.137–0.230]; PFWE=0.016). APOE4 carriers, but not non-carriers, experienced significant connectivity decreases from before to 6 weeks after surgery between several brain regions including between the left posterior cingulate cortex and left angular gyrus (β [95% CI], –0.196 [–0.256 to –0.136]; PFWE=0.001). Most preoperative and postoperative functional connectivity differences did not change after controlling for preoperative CSF Aβ levels. Conclusions Postoperative change trajectories for cognition and CSF Aβ, tau or p-tau levels did not differ between community dwelling older APOE4 carriers and non-carriers. APOE4 carriers showed greater preoperative functional connectivity and greater postoperative decreases in functional connectivity in key Alzheimer's disease-risk regions, which occur via Aβ-independent mechanisms.

Natural products that contain distinctive chemical functionality can serve as useful starting points to develop Nature’s compounds into viable therapeutics. Peptide natural products, an under-represented class of medicines, such as ribosomally synthesized and post-translationally modified peptides (RiPPs), often contain noncanonical amino acids and structural motifs that give rise to potent biological activity. However, these motifs can be difficult to obtain synthetically, thereby limiting the transition of RiPPs to the clinic. Aminovinyl cysteine containing peptides, which display potent antimicrobial or anticancer activity, possess an intricate C-terminal ring that is critical for bioactivity. To date, successful methods for the total chemical synthesis of such peptides are yet to be realized, although several advancements have been achieved. In this perspective, we review this burgeoning class of aminovinyl cysteine peptides and critically evaluate the chemical strategies to install the distinct aminovinyl cysteine motif.