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The ability to predict the thermodynamic properties of amine species in CO2-loaded aqueous solutions, including their deprotonation (pKa) and carbamate to bicarbonate reversion (pKc) equilibrium constants and their corresponding standard reaction enthalpies, is of critical importance for the design of improved carbon capture solvents. In this study, we used isocoulombic forms of both reactions to determine these quantities for a large set of aqueous alkanolamine solvent systems. Our hybrid approach involves using classical molecular dynamics simulations with the general amber force field (GAFF) and semi-empirical AM1-BCC charges (GAFF/AM1-BCC) in the solution phase, combined with high-level composite quantum chemical ideal-gas calculations. We first determined a new force field (FF) for the hydronium ion (H3O+) by matching to the single experimental pKa data point for the well-known monoethanolamine system at 298.15 K. We then used this FF to predict the pKa values for 76 other amines at 298.15 K and for all 77 amines at elevated temperatures. Additionally, we indirectly relate the H3O+ hydration free energy to that of H+ and provide expressions for intrinsic hydration free energy and enthalpy of the proton. Using the derived H3O+ FF, we predicted the pKa values of a diverse set of alkanolamines with an overall average absolute deviation of less than 0.72 pKa units. Furthermore, the derived H3O+ FF is able to predict the protonation enthalpy of these amines when used with the GAFF. We also predicted the carbamate reversion constants of the primary and secondary amine species in the data set and their corresponding standard heats of reaction, which we compared with the scarcely available experimental data, which are often subject to significant uncertainty. Finally, we also described the influence of electronic and steric effects of different molecular fragments/groups on the stabilities of the carbamates.

Patients, clinicians, researchers, and policy makers have long called for greater integration of services for people with co-occurring mental and substance use disorders. Decades later, these services remain fragmented in psychiatry across much of the United States. Mounting deaths from drug-related overdoses call for renewed focus on bringing substance use into the center of psychiatric services. This Open Forum explores factors within the field of psychiatry, including insufficient training related to substance use, prevalent stigma surrounding substance use, and limited availability of co-occurring disorder specialists, that reinforce this divide and offers solutions for better addressing substance use disorders in psychiatric care.

Debates about the ethics of health care and medical research in contemporary pluralistic democracies often arise partly from competing religious and secular values. Such disagreements raise challenges of balancing claims of religious liberty with claims to equal treatment in health care. This paper proposes several mid-level principles to help in framing sound policies for resolving such disputes. We develop and illustrate these principles, exploring their application to conscientious objection by religious providers and religious institutions, accommodation of religious priorities in biomedical research, and treatment of patients’ religious views in doctor–patient encounters. Given that no sound set of guiding principles yields precise solutions for every policy dispute, we explore how morally sound democracies might deliberatively resolve such policy issues, following our proposed principles. Taken together and carefully interpreted, these principles may help in guiding difficult decision making in the indefinitely large realm where government, medical providers, and patients encounter problems concerning religion and medicine.

We calculated ideal-gas thermochemical properties (molar enthalpy, entropy, Gibbs energy, and heat capacity, Cp) for 30 primary and 12 secondary alkanolamines and their neutral, protonated, and car...

We present a general atomistic simulation framework for efficient reactive equilibrium calculations in dilute solutions, and its application to CO2 reactive absorption in aqueous alkanolamine solut...

The Le Châtelier Principle is one of the most important concepts in chemistry, and it has been the topic of many publications over the years. However, its meaning and application are often fraught with misunderstanding and confusion. As a suggested replacement, we present herein a precise general statement that we call the Basic Le Châtelier Principle (BLCP), which is in keeping with a common thread in Le Châtelier’s original statements. The BLCP is formulated as a consequence of well-known properties of a simple but general optimization problem, which elevates its range of application beyond chemistry to any phenomenon governed by such an optimization principle. We show applications of the BLCP to simple example problems in economics and in physics, in addition to the usual chemistry problems,. Following a brief outline of Le Châtelier’s original statements, we formulate the BLCP, which incorporates the notion of “de signe contraire” (of opposite sign), common to all his statements. It arises by abstracting the chemical reaction equilibrium problem (CREP) in the single-reaction case to the general problem of minimizing a differentiable function $$f(x;\{p_j\})$$ , where x is the single independent variable and $$\{p_j\}$$ is a set of parameters. The BLCP arises from an exact expression for the dependence of the sign of the incremental change in the optimal solution $$x^*$$ on the sign of the incremental change in a parameter, which is derived using techniques taught in an early undergraduate calculus course. When translated back to the CREP, this yields unambiguous expressions for the sign of the incremental change in the equilibrium reaction extent, $$\xi ^*$$ , arising from an incremental change in each of T, P, the initial species amounts, $$\{n_i^0\}$$ , and the standard reaction free energy change, $$\varDelta G^{\Box }$$ . Special emphasis is placed on the requirement that f must satisfy a positive definite second derivative condition, for which we present a proof in the case of multiple reactions in an ideal solution model system. We also briefly consider the extension of the single-variable BLCP derived herein to the case of multiple independent variables and to finite parameter perturbations.

Despite the fact that psychedelics were proscribed from medical research half a century ago, recent, early-phase trials on psychedelics have suggested that they bring novel benefits to patients in the treatment of several mental and substance use disorders. When beneficial, the psychedelic experience is characterized by features unlike those of other psychiatric and medical treatments. These include senses of losing self-importance, ineffable knowledge, feelings of unity and connection with others and encountering ‘deep’ reality or God. In addition to symptom relief, psychedelic experiences often lead to significant changes in a patient’s personality and worldview. Focusing on the case of psilocybin, we argue that the peculiar features of psychedelics pose certain novel risks, which warrant an enhanced informed consent process–one that is more comprehensive than what may be typical for other psychiatric medications. We highlight key issues that should be focused on during the consent process and suggest discussion prompts for enhanced consent in psychedelic psychiatry. Finally, we respond to potential objections before concluding with a discussion of ethical considerations that will arise as psychedelics proceed from highly controlled research environments into mainstream clinical psychiatry.

Purpose: The purpose of this study was to determine whether there is a difference in the change in cross-sectional area (CSA) of the median nerve in patients undergoing carpal tunnel release (CTR) based on surgical technique and whether this change is associated with changes in patient-reported outcomes evaluated using the Carpal Tunnel Syndrome Assessment Questionnaire. Methods: Individuals with carpal tunnel syndrome were evaluated with ultrasound and the CTSAQ before and 6 weeks after surgery. Patients were eligible for inclusion if they underwent either a mini-open CTR (MOCTR) or endoscopic CTR (ECTR). A single surgeon performed all surgeries. Changes in median nerve CSA, Carpal Tunnel Syndrome Assessment Questionnaire scores, and their associated surgical technique (MOCTR vs ECTR) were analyzed. Results: A total of 77 patients were enrolled, 13 of whom were lost to follow-up, which left 64 for analysis. Of those, 42 patients underwent ECTR and 22 MOCTR. Mean age was 55 years; there were 52 women and 12 men. Mean changes in CSA for endoscopic and mini-open techniques from before to 6 weeks after surgery were –1.9 mm2 (95% confidence interval [CI], –1.1 to –2.7) and +0.6 mm2 (95% CI, –1.6 to 0.4), respectively. Mean Symptom Severity Scores improved after endoscopic and mini-open release by 1.7 (95% CI, 1.4–2.1) and 1.5 (95% CI, 1.2–1.9), respectively. Mean Functional Status Scores improved after endoscopic and mini-open release by 1.2 (95% CI, 0.9–1.9) and 0.7 (95% CI, 0.03–1.3), respectively. Conclusions: Patients undergoing ECTR demonstrated decreased median nerve CSA, whereas those undergoing MOCTR demonstrated increased median nerve CSA at 6 weeks. All patients undergoing surgical intervention demonstrated improvement in both Symptom Severity Scores and Functional Status Scores after surgery. Whereas both techniques successfully improve patient outcome scores, an increase in CSA after MOCTR may be seen in the initial postoperative period, potentially contributing to a slower short-term improvement in outcome in functional scores compared with ECTR. Type of study/level of evidence: Therapeutic IV. Key words: Carpal tunnel release, Cross-sectional area, Endoscopic, Mini-open, Ultrasound

This article traces the history of factionalism in policy making and advocacy for persons with serious mental illness from deinstitutionalization to the present. The authors draw on deliberative democratic theory to illustrate how factionalist advocacy causes advocates and policy makers to fail in their duties to represent and develop policy in support of people with serious mental illness. The authors discuss how this factionalism has bred distrust and undermined efforts to address the needs of people with serious mental illness. They propose the formation of a Public Mental Health Policy Commission, guided by principles of deliberative democracy, to overcome factionalism and to improve policy making to meet the needs of people with serious mental illness. The commission must include a diverse array of stakeholders, especially individuals with lived experience of serious mental illness.

The spectrophotometric determination of the percent composition of an aspirin tablet is a common first-year, general chemistry undergraduate laboratory procedure. The experiment requires that a known amount of pure acetylsalicylic acid be quantitatively converted into the soluble disodium salicylic acid that is further reacted with excess iron(III) chloride solution to form a deep blue tetraaqua-octahedral complex. This complex, through serial dilutions, is used to construct a Beer’s law plot that may be used to determine the concentration of aspirin. In a novel twist, this paper describes how the same Beer’s law plot can be used to determine the concentration of iron in the iron(III) complex, which is then used to determine the concentration of the original iron(III) chloride solution used to make the aspirin–iron(III) complex. The method has been adapted by high school students in determining iron concentrations in stream waters.

Knowledge of aqueous protonation constants (pKa) of chemical species is of significant importance in CO2 reactive absorption system design. Their theoretical prediction has mainly relied on implici...

Classic psychedelics and related substances have shown promising initial research results. However, they raise a number of relatively novel ethical and policy challenges in light of their psychoactive properties, their emergence from the unregulated "underground" settings in which they have been used, their rapid commercialization, and the means and speed with which they are moving from Schedule 1 status to legalized use. All of these issues are affected by the current limits to the evidence base on use of psychedelics. Here we survey these novel challenges, illustrating the issues raised regarding each, and offering suggestions for how to address them.

Multiple documents from the White House, Congress, and from within the Department of Defense describe the imperative to work with allies and partners toward long-term advancement of the U.S. and pa...

In children with brachial plexus birth palsy (BPBP) undergoing tendon transfers to augment shoulder external rotation, it is unclear whether transfer of the latissimus dorsi with its combined latissimus dorsi and teres major (cLT) versus isolated teres major (iTM) tendon transfer yield different outcomes.Records of patients with BPBP who underwent shoulder tendon transfers to augment external rotation were retrospectively reviewed. Transfer type (cLT or iTM) was considered indiscriminate by virtue of surgeon preference. Modified Mallet Scale (mMS) and Active Movement Scale scores were recorded. Patients with12 months' follow-up, C7 or lower palsy, humeral osteotomy, shoulder procedure(s) within 8 months, microsurgery within 1 year, or recurrent glenohumeral subluxation confirmed by postoperative imaging were excluded. Matched cohorts were identified within each tendon transfer group to yield similar preoperative shoulder function and glenohumeral alignment status. Outcomes for all tendon transfers as well as differences between cLT and iTM cohorts were analyzed.Among 121 cLT and 34 iTM transfers, 49 cLT and 14 iTM met the inclusion criteria. Subsequent matching of cohorts yielded 28 patients (14 cLT and 14 iTM). Average age at time of transfer was 3.0±1.4 years. Follow-up averaged 4.1±3.1 years. There were no statistically significant preoperative differences between cohorts, thus matching criteria were validated. Regardless of tendon(s) transferred, mMS external rotation improved (2.2 to 3.5, P0.001), whereas mMS internal rotation decreased (3.8 to 3.2, P0.001). When comparing matched cohorts, cLT transfer produced a greater mMS external rotation improvement than iTM (2.1 vs. 1.5, respectively; P=0.025). Loss of midline function (defined as mMS external rotation3) occurred in 5 (35.7%) cLT and 2 (14.3%) iTM patients.Both cLT or iTM transfer are effective at augmenting shoulder external rotation in children with C5-C6 BPBP. Furthermore, cLT transfers may yield a larger improvement in external rotation in certain patients. However, both techniques slightly decrease shoulder internal rotation. Given that more total cLT patients lost midline function among matched cohorts, iTM transfer may still be considered when limited midline function is a concern.Level III.

Constructing regularly catalytic arrays is essential for electrochemical catalysis, especially for hydrogen evolution reaction (HER). In this work, two-dimensional zeolitic imidazolate framework (ZIF) arrays were chosen as templates to construct few-layer MoS2-decorated hollow CoP. By coupling MoS2 nanosheets arrays and two-dimensional ZIF-67 derived CoP, the advantages of the active sites of MoS2 nanosheets edges and CoP are combined for efficient HER, which can drive a current density of 100 mA/cm2 in both acid (91 mV) and alkaline (135 mV) solutions for 10 h. Furthermore, the prepared catalyst can reach a current density of 10 mA/cm2 with overpotentials of only 53 and 77 mV in 0.5 M H2SO4 and 1 M KOH, respectively. Most importantly, we believe replacing ZIF-67 powders with 2D ZIF-67 arrays can boost the electrochemical activities for HER and this method can provide us a guideline for the future application of two-dimensional ZIF-67 arrays to construct efficient electrocatalysts.

Exploring more active, low-cost and stable electrocatalysts to substitute precious noble metals has always been a research focus on the application of water splitting. In this study, firstly, we prepared CoFe-layered double hydroxide (CoFe-LDH) via one-step electrodeposition. The CoFe-LDH nanosheets grew on the nickel foam and formed a 3D hierarchical structure, making the CoFe-LDH exhibit excellent activity for oxygen evolution reaction (OER). The overpotential was 250 mV and the Tafel slope is 35 mV dec−1 at 10 mA cm−2 in alkaline condition. With such a 3D porous structure as a framework, we fabricated CoFe phosphides using a solid-phase reaction. After phosphorization, the nanosheets retained the original 3D porous structure and electrochemical performance for hydrogen evolution reaction had been greatly enhanced. The overpotential in alkaline condition was 58 mV and the Tafel slope is 46 mV dec−1 at 10 mA cm−2. The CoFe-LDH and CoFe-P with Ni foams were used as asymmetric electrodes for overall water splitting. At the potential of 1.51 V, this electrolysis apparatus can reach a current density of 10 mA cm−2 in 1 M KOH, which is superior to all of the reported non-precious metal based ones.

We develop a computationally efficient molecular-based simulation algorithm for chemical reaction equilibria in liquids containing neutral and ionic species, which is based on the combination of classical force field and ab initio calculations and permits calculations involving very small species concentrations. We show its application to the reactive absorption of CO2 in aqueous monoethanolamine (MEA) solvent as a benchmark case, the first time that a quantitatively accurate predictive approach requiring no experimental data has been successfully applied to calculate all solution species concentrations for this system, including the partial pressure of CO2 above the solution. The Reaction Ensemble Monte Carlo (REMC) algorithm, the only other generally applicable approach, requires special system-dependent Monte Carlo enhancements for its implementation, and to detect species with very small concentrations requires long simulation times and/or large system sizes. In contrast, the proposed algorithm can be straightforwardly implemented for systems of any molecular complexity using a standard Molecular Dynamics (MD) simulation package capable of calculating free energy changes and can calculate small species concentrations with normal simulation times and system sizes. In addition, the inherent parallelization capability of MD (which is problematic for MC-based approaches) enables the algorithm's computationally efficient implementation. The H2O-MEA-CO2 benchmark system has been the subject of many previous studies based on macroscopic thermodynamic modeling, which primarily involves fitting their parameters (of which reaction p K values are the most important) to experimental data measurements. To make contact with such approaches, we show the translation of the molecular-based quantities to the direct prediction of these parameters and calculate reaction equilibrium in the framework of a Henry Law-based chemical potential model. We consider both the ideal solution form and its extension using the Davies equation for the species activity coefficients. We study a range of temperatures and CO2 solution loadings in a 30 wt % MEA solution and incorporate an uncertainty analysis in our methodology. We find that the uncertainties of the simulated solution species compositions are comparable to those of the available experimental data. We report predictions of minor species compositions of very small magnitude, for which experimental measurements are typically extremely challenging.

Transition-metal alloys have attracted a great deal of attention as an alternative to Pt-based catalysts for hydrogen evolution reaction (HER) in alkaline. Herein, a facile and convenient strategy to fabricate Co3Mo binary alloy nanoparticles nesting onto molybdenum oxide nanosheet arrays on nickel foam is developed. By modulating the annealing time and temperature, the Co3Mo alloy catalyst displays a superior HER performance. Owing to substantial active sites of nanoparticles on nanosheets as well as the intrinsic HER activity of Co3Mo alloy and no use of binders, the obtained catalyst requires an extremely low overpotential of only 68 mV at 10 mA cm-2 in alkaline, with a corresponding Tafel slope of 61 mV dec-1. At the same time, the catalyst demonstrates excellent stability during the long-term measurements. The density functional theory calculation provides a deeper insight into the HER mechanism, unveiling that the active sites on the Co3Mo-based catalyst are Mo atoms. This strategy of combining catalytic active species with hierarchical nanoscale materials can be extended to other applications and provides a candidate of nonnoble metal catalysts for practical electrochemical water splitting.

Due to their synergistic and tunable effects, bimetallic alloy systems have recently attracted considerable attention as superior catalysts. Herein, Pd-Co bimetallic alloy nanoparticles were uniformly deposited onto CuO nanosheet supports. This nanostructured catalyst was first shown to be an effective catalyst to convert N2 to NH3 in 0.1 M KOH with a yield of 10.04 μg h-1 mg-1cat. and a faradaic efficiency of 2.16%. The catalyst also performed well in the Suzuki-Miyaura coupling reaction at room temperature without an inert atmosphere and any toxic solvents. Thus, the catalyst is consistent with the principles of green chemistry. Due to the synergistic effects, this bimetallic Pd-Co catalyst shows higher catalytic activity than its monometallic counterparts. Moreover, the Pd/Co ratio was tuned to achieve the best catalytic performance. Finally, the Pd-Co/CuO catalyst presented good stability and recyclability. The superior catalytic activity of the bimetallic alloy catalyst make it an alternative material for catalytic applications in the future.

Introduction Carrying standard safety gear (beacon, probe, and shovel), planning a route of descent, and recreating with companions can help to mitigate the risk of injury or death resulting from avalanches in the backcountry. The goal of this study was to identify factors associated with performance of these safety practices. Methods A convenience sample of backcountry skiers and snowboarders was surveyed in 2016 at the backcountry gates of Jackson Hole Mountain Resort. Each participant was surveyed on characteristics including skill level, sex, age, prior avalanche education, and residency in the Jackson Hole area. Safety practices were also measured against avalanche hazard forecasts. Correlations were assessed using Fisher's exact testing. Results A total of 334 participants were surveyed. Factors associated with carrying avalanche safety gear included higher expertise, being a resident of the Jackson Hole area, and prior avalanche education. Factors associated with having a planned route of descent included higher expertise and being a resident of the Jackson Hole area. Factors associated with recreating with companions included younger age and lower expertise. Sex had no association with any of the surveyed safety practices. Participants were less likely to carry avalanche safety gear on low avalanche hazard days. Conclusions Certain individual characteristics of backcountry skiers and snowboarders are associated with increased frequency of adherence to recommended safety practices. These findings suggest that particular categories of backcountry recreationists may benefit from further avalanche safety education. The results of this study could help direct future educational efforts among backcountry recreationists.

Psychiatric research often poses special ethical concerns. This chapter first provides historical context, including scandals that stoked public concern about psychiatric research and led to the promulgation of canonical documents and bioethics scholarship, and then explores issues related to the decision-making capacity and safety of participants—including the use of placebos and washout periods, the design of suicide prevention studies, and research in emergency psychiatry. The chapter then describes how shifting models of psychiatric nosology have precipitated conflicts in the determination of research priorities. Finally, the chapter attends to emerging issues related to research in psychedelic psychiatry and the use of artificial intelligence and social media by investigators.