Direct Admission to Hospital for Children in the United States.

One in four unscheduled hospital admissions for children and adolescents in the United States occurs via direct admission, defined as hospital admission without first receiving care in the hospital's emergency department. The purpose of this policy statement is to present recommendations to optimize the quality and safety of this hospital admission approach for children. Recommendations included in this policy statement provide guidance related to: (i) direct admission written guidelines, (ii) clear systems of communication between members of the health care team and with families of children requiring admission, (iii) triage systems to identify patient acuity and disease severity, (iv) identification of hospital resources needed to support direct admission systems of care, (v) consideration of patient populations that may be at increased risk of adverse outcomes during the hospital admission process, (vi) addressing the relevance of local factors and resources, and (vii) ongoing evaluation of direct admission processes and outcomes. The recommendations included in this policy statement are intended to support the implementation of safe direct admission processes and to foster awareness of outcomes associated with this common portal of hospital admission.

An Open Repository of Real-Time COVID-19 Indicators

The COVID-19 pandemic presented enormous data challenges in the United States. Policy makers, epidemiological modelers, and health researchers all require up-to-date data on the pandemic and relevant public behavior, ideally at fine spatial and temporal resolution. The COVIDcast API is our attempt to fill this need: operational since April 2020, it provides open access to both traditional public health surveillance signals (cases, deaths, and hospitalizations) and many auxiliary indicators of COVID-19 activity, such as signals extracted from de-identified medical claims data, massive online surveys, cell phone mobility data, and internet search trends. These are available at a fine geographic resolution (mostly at the county level) and are updated daily. The COVIDcast API also tracks all revisions to historical data, allowing modelers to account for the frequent revisions and backfill that are common for many public health data sources. All of the data is available in a common format through the API and accompanying R and Python software packages. This paper describes the data sources and signals, and provides examples demonstrating that the auxiliary signals in the COVIDcast API present information relevant to tracking COVID activity, augmenting traditional public health reporting and empowering research and decision-making.

Enantioselective sulfonylation reactions mediated by a tetrapeptide catalyst.

While Nature excels at performing selective modifications of complex polyfunctional molecules through the use of tailoring enzymes, synthetic chemistry has lagged behind in this regard. In prior work, we have applied a biomimetic approach to this problem, developing small peptides to achieve various group transfer reactions on polyol substrates with high enantio- or regioselectivity. The utility of sulfonates as synthetic building blocks and the scarcity of direct, selective methods for their preparation prompted our investigation into this area. In this article we report the development of a pi-methyl histidine-based tetrameric peptide that effects the desymmetrization of meso-1,3-diols through enantioselective (mono)sulfonylation. The catalyst exhibits structural similarities to another catalyst found to be effective in orthogonal group transfers, but results in modification of the enantiotopic alcohol. The practical and mechanistic implications of this discovery may extend beyond synthetic considerations and provide analogies to the diverse roles of histidine in enzyme active sites.

Catalytic intermolecular amination of C-H bonds: method development and mechanistic insights.

Reaction methodology for intermolecular C-H amination of benzylic and 3 degrees C-H bonds is described. This process uses the starting alkane as the limiting reagent, gives optically pure tetrasubstituted amines through stereospecific insertion into enantiomeric 3 degrees centers, displays high chemoselectivity for benzylic oxidation, and enables the facile preparation of isotopically enriched 15N-labeled compounds. Access to substituted amines, amino alcohols, and diamines is thereby made possible in a single transformation. Important information relevant to understanding the initial steps in the catalytic cycle, reaction chemoselectivity, the nature of the active oxidant, and pathways for catalyst inactivation has been gained through mechanistic analysis; these studies are also presented.

Expanding the scope of C-H amination through catalyst design.

Analysis of the mechanism for Rh-mediated C-H amination has led to the development of a remarkably effective dinuclear Rh catalyst derived from 1,3-benzenedipropionic acid. This unique complex, Rh2(esp)2, is capable of promoting both intra- and intermolecular C-H oxidation reactions, and in all cases is superior to Rh2(O2CtBu)4. For the first time, C-H insertion is described with urea and sulfamide substrates to give 1,2- and 1,3-diamine derivatives, respectively. In addition, intermolecular amination of benzylic and secondary C-H bonds is shown to proceed efficiently even under conditions in which the starting alkane is employed as the limiting reagent.

Novel iminium ion equivalents prepared through C-H oxidation for the stereocontrolled synthesis of functionalized propargylic amine derivatives.

Access to stereochemically complex, polyfunctionalized amine derivatives is made possible using novel oxathiazinane N,O-acetal starting materials. These heterocycles are prepared through intramolecular sulfamate ester C-H insertion with a Rh(2+)-carboxylate catalyst and PhI(OAc)(2) as the terminal oxidant. Such compounds function as unique iminium ion equivalents to which nucleophilic alkynylzinc reagents add smoothly in the presence of BF(3).OEt(2). The coupled products are isolated in high yield (63-92%) and with good levels of diastereoinduction (6 --> 20:1). The alkyne-substituted oxathiazinanes serve as versatile building blocks and may be further manipulated through nucleophilic ring-opening reactions of the sulfamate core. The efficient construction of 1,7,8-trihydroxyindolizidine in six steps and in 34% overall yield highlights the power of these combined methods for synthesis.