Formation of Red Elemental Selenium from Seleniferous Oxyanions: Deoxygenation by a Homogeneous Iron Catalyst.

Seleniferous oxyanions are groundwater contaminants from both anthropogenic and natural sources, while pure amorphous selenium nanoparticles have a variety of industrial applications. Biology can achieve the multicomponent 6 e-/8 H+ reduction of selenate to amorphous selenium using multiple metalloenzymes, like selenate and selenite reductase. Inspired by biology, we developed a new homogeneous system that can generate pure elemental selenium with no caustic waste. The stoichiometric reductions of selenate, selenite, and selenium dioxide with an iron(II) complex produced an iron(III)-oxo and red elemental selenium, the latter of which has been characterized by a variety of spectroscopic techniques. The catalytic reduction of SeO42- and SeO32- directly to amorphous Se and isolated as Se=PPh3 is reported with a turnover number of 12 and 7, respectively.

Sickle cell disease: Contributing factors and radiological assessments.

Sickle Cell Disease (SCD) is genetically described as an autosomal blood disorder resulting from the presence of a mutated form of hemoglobin. Morbidity, frequency of crisis, degree of anemia, and organ systems involved vary considerably per patient. Dental health professionals and other specialists commonly request comprehensive medical consultations prior to performing complex periodontal, endodontic, and surgical procedures. In order to have successful dental outcomes and minimize posttreatment dental complications, relevant disease indicators are noted. This review is to raise awareness of the impact of oral diseases in patients with sickle cell disease and to emphasize the importance of full medical disclosure, radiographic interpretation, and a well-documented medical history, and a well-written consultation which can guide treatment planning and greatly improve the course of dental treatment.

Nutrition Considerations in Patients with Functional Diarrhea.

PURPOSE: Functional diarrhea (FD) is a functional gastrointestinal disorder that affects a great percentage of the population and has damaging nutritional and psychological effects. In this review, evidence has been assessed and analyzed to provide nutrition considerations and recommendations for patients with functional diarrhea. RECENT FINDINGS: The traditional irritable bowel syndrome (IBS) diet, the low FODMAP diet, and general recommendations for diarrhea have been established as interventions for FD. Additionally, nutrition outcomes such as vitamin and mineral deficiencies, hydration levels, and mental health status should be at the forefront of assessment. The importance of medical management of FD and IBS-D is established, with many existing evidence-based recommendations and approved medications available. Nutrition management of FD from a registered dietitian/dietitian nutritionist, from symptom control to dietary advice, is imperative. There are no "one-size-fits-all" approaches to nutrition management of FD, but there is promising literature that can shape personalized nutrition interventions from a registered dietitian.

People's reports of unexpected events for everyday scenarios: Over 1000 textual responses, human-labelled for valence/sentiment, controllability and topic category.

With this article, we present a repository containing datasets, analysis code, and some outputs related to a paper in press at Cognition. The data were collected as part of a pre-test, pilot test, and main study all designed in SurveyGizmo and participants recruited via Prolific.co (combined N=303). Datasets consist of raw and annotated data, where participant responses are free-text entries about what unexpected events might occur after a series of events, presented them with based on everyday scenarios. The code consists of all computational additions to the data, and analysis carried out for the results presented in the article. This data is released for the purpose of transparency and to allow for reproducability of the work. This human-labelled data should also be of use to machine learning researchers researching text analytics, natural language processing and sources of common-sense knowledge.

Evaluating the efficacy of alfaxalone in corn snakes (Pantherophis guttatus).

OBJECTIVE: Alfaxalone is a popular veterinary anesthetic; however, research on this anesthetic in snakes has been limited to ball pythons, garter snakes and several Australian species. The objective was to evaluate the anesthetic effects of alfaxalone in corn snakes (Pantherophis guttatus), a popular pet snake. STUDY DESIGN: Prospective, randomized crossover study. ANIMALS: A total of eight corn snakes. METHODS: In phase I, snakes were subcutaneously administered three doses of alfaxalone (5, 10 and 15 mg kg-1) in the cranial third of the body to determine the most effective dose. In phase II, a dose of 15 mg kg-1 was administered in the cranial and caudal thirds of the snakes to determine if injection site affected anesthesia duration. Heart rate (HR), respiratory rate (fR), righting reflex, escape response, tail pinch, needle prick and tongue flick were monitored at baseline and 5 minute intervals until the snakes fully recovered. RESULTS: Duration of anesthesia differed significantly, with higher doses lasting longer than lower doses: 5 mg kg-1 [23.8 ± 4.4 (15-30) minutes]; 10 mg kg-1 [40.6 ± 9.4 (25-55) minutes]; and 15 mg kg-1 [56.9 ± 8.4 (50-70) minutes], mean ± standard deviation (range). The tail pinch reflex was not completely lost in phase 1. There was a significant change in fR over time, but this was not related to dose. HR was not different by time or dose. Duration of anesthesia was not different after administration of alfaxalone (15 mg kg-1) in the cranial third versus the caudal third of the body; however, there was a significant decrease in HR and fR at this dose, regardless of injection site. CONCLUSIONS AND CLINICAL RELEVANCE: Based on these results, alfaxalone (15 mg kg-1) provides adequate anesthesia for brief procedures or intubation; however, additional analgesia is required for painful procedures.

Radical Rebound Hydroxylation Versus H-Atom Transfer in Non-Heme Iron(III)-Hydroxo Complexes: Reactivity and Structural Differentiation.

The characterization of high-valent iron centers in enzymes has been aided by synthetic model systems that mimic their reactivity or structural and spectral features. For example, the cleavage of dioxygen often produces an iron(IV)-oxo that has been characterized in a number of enzymatic and synthetic systems. In non-heme 2-oxogluterate dependent (iron-2OG) enzymes, the ferryl species abstracts an H-atom from bound substrate to produce the proposed iron(III)-hydroxo and caged substrate radical. Most iron-2OG enzymes perform a radical rebound hydroxylation at the site of the H-atom abstraction (HAA); however, recent reports have shown that certain substrates can be desaturated through the loss of a second H atom at a site adjacent to a heteroatom (N or O) for most native desaturase substrates. One proposed mechanism for the removal of the second H-atom  involves a polar-cleavage mechanism (electron transfer-proton transfer) by the iron(III)-hydroxo, as opposed to a second HAA. Herein we report the synthesis and characterization of a series of iron complexes with hydrogen bonding interactions between bound aquo or hydroxo ligands and the secondary coordination sphere in ferrous and ferric complexes. Interconversion among the iron species is accomplished by stepwise proton or electron addition or subtraction, as well as H-atom transfer (HAT). The calculated bond dissociation free energies (BDFEs) of two ferric hydroxo complexes, differentiated by their noncovalent interactions and reactivity, suggest that neither complex is capable of activating even weak C-H bonds, lending further support to the proposed mechanism for desaturation in iron-2OG desaturase enzymes. Additionally, the ferric hydroxo species are differentiated by their reactivity toward performing a radical rebound hydroxylation of triphenylmethylradical. Our findings should encourage further study of the desaturase systems that may contain unique H-bonding motifs proximal to the active site that help bias substrate desaturation over hydroxylation.

Rapid Seafood Species Identification Using Chip-Based Capillary Electrophoresis and Protein Pattern Matching.

Authenticity is crucial to the seafood industry, as substitution and mislabeling have important economic, environmental, and food safety consequences. To address this problem, protein profiling and software algorithm techniques were developed to classify fish muscle samples by species. The method uses water-based protein extraction, chip-based microfluidic electrophoresis (Agilent 2100 Bioanalyzer) for the analysis of high abundance fish muscle proteins, and a novel data analysis method for species-specific protein pattern recognition. The method's performance in distinguishing commercially important fish from commonly reported substitutions was evaluated using sensitivity, specificity, and accuracy determinations with all three performance measures at >98% for common substitutions. This study demonstrates that uncooked seafood products of commercially important species of catfish, snapper, and grouper can be rapidly distinguished from commonly substituted species with a high level of confidence. A tiered testing approach to seafood species verification by sequentially applying a rapid screening method and DNA testing is proposed to more effectively ensure accurate product labeling.

A bioinspired iron catalyst for nitrate and perchlorate reduction.

Nitrate and perchlorate have considerable use in technology, synthetic materials, and agriculture; as a result, they have become pervasive water pollutants. Industrial strategies to chemically reduce these oxyanions often require the use of harsh conditions, but microorganisms can efficiently reduce them enzymatically. We developed an iron catalyst inspired by the active sites of nitrate reductase and (per)chlorate reductase enzymes. The catalyst features a secondary coordination sphere that aids in oxyanion deoxygenation. Upon reduction of the oxyanions, an iron(III)-oxo is formed, which in the presence of protons and electrons regenerates the catalyst and releases water.