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The number of children who are removed into formal foster care in the USA remains stubbornly high. To address this concern, child welfare agencies are seeking safe ways of diverting low-risk cases from formal foster care to informal alternative care. However, little is known about the outcomes and wellbeing of children who spend some time in informal placements, particularly in the homes of unrelated caregivers. The current study reports results from a pre-registered, experimental evaluation of Safe Families for Children, a voluntary hosting program for children whose parents are being investigated for child maltreatment. Drawing on a Bayesian paradigm, it analyzes the effects of the hosting program in both formative and summative randomized controlled trials conducted in downstate Illinois. Findings indicate that the intervention deflects alleged and indicated victims of maltreatment from the formal foster care system to the voluntary alternative care of host families. The program demonstrates positive or null effects across a variety of child welfare outcomes, including subsequent episodes of indicated maltreatment and return to or maintenance in the parental home. Findings from this work contribute to the ongoing debate about the benefits and risks of informal non-kin care as a preventive alternative to the removal of children into formal foster care.

Polycrystalline Ni, Pd, Cu, Ag, and Au foils exposed to nonthermal plasma (NTP)-activated N2are found to exhibit a vibrational feature near 2200 cm–1in polarization-modulation infrared reflection-absorption spectroscopy (PM-IRAS) observations that are not present in the same materials exposed to N2under nonplasma conditions. The feature is similar to that reported elsewhere and is typically assigned to chemisorbed N2. We employ a combination of temperature-dependent experiments, sequential dosing, X-ray photoelectron spectroscopy, isotopic labeling, and density functional theory calculations to characterize the feature. Results are most consistent with a triatomic species, likely NCO, with the C and O likely originating from ppm-level impurities in the ultrahigh-purity (UHP) Ar and/or N2gas cylinders. The work highlights the potential for nonthermal plasmas to access adsorbates inaccessible thermally as well as the potential contributions of ppm-level impurities to corrupt the interpretation of plasma catalytic chemistry.

Child neglect is the most common type of child maltreatment and neglect is present in 80% of the child fatalities attributed to maltreatment. The disruption of child maltreatment must then prioritize neglect prevention. To date, maltreatment prevention efforts have been most effective for physical and sexual abuse. However, traditional prevention strategies and the supporting research have proven to be less effective at preventing neglect. We posit that a new approach of focusing on macro-level factors, such as economies, labor markets, and governmental affairs, should be investigated. These macro-level factors play a key, yet underexplored role in family circumstances, and they strongly influence parents’ ability to consistently provide safe and sufficient environments for their children. Existing research, policies, and programs have successfully improved the health and safety of children in many areas including reducing physical and sexual abuse and reducing child deaths from disease and car accidents. Yet, these strategies have not been implemented in the area of child neglect, partially because the research community does not fully understand the causes of neglect. To inform new directions for child protection, we propose shifting the focus of research on neglect away from individual and family-level factors of indicated populations. And, we suggest focusing on macro-level factors that, while receiving far less attention from researchers, show initial promise for understanding the causal pathways of neglect and identifying policies for universal prevention. We conclude with recommendations for advancing the precision and quality of research in this area.

The creation and ethylene oligomerization function of silica-anchored group 4 metal (M = Ti, Zr, Hf) hydrides as a function of the anchor site structure are explored using density functional theory models. Oligomerization potential energy surfaces are sensitive both to the metal ion and to the structure of the anchoring site. Microkinetic models predict the oligomerization rate and degree of polymerization as a function of the site, temperature, and reactant pressures. Intrinsic catalytic activity is predicted to vary as Ti < Zr > Hf down the group, irrespective of site model, while absolute rates and product distributions are strongly sensitive to the site model, temperature, and hydrogen pressure. Catalysts based on these sites are plausible candidates for high-temperature ethylene oligomerization of interest for generating fuels from ethylene, but selectivity is expected to require careful control over the site structure and reaction conditions.

Abstract: Determination of high-quality small protein structures by nuclear magnetic resonance (NMR) methods generally requires acquisition and analysis of an extensive set of structural constraints. The process generally demands extensive backbone and sidechain resonance assignments, and weeks or even months of data collection and interpretation. Here we demonstrate rapid and high-quality protein NMR structure generation using CS-Rosetta with a perdeuterated protein sample made at a significantly reduced cost using new bacterial culture condensation methods. Our strategy provides the basis for a high-throughput approach for routine, rapid, high-quality structure determination of small proteins. As an example, we demonstrate the determination of a high-quality 3D structure of a small 8 kDa protein, E. coli cold shock protein A (CspA), using <4 days of data collection and fully automated data analysis methods together with CS-Rosetta. The resulting CspA structure is highly converged and in excellent agreement with the published crystal structure, with a backbone RMSD value of 0.5 Å, an all atom RMSD value of 1.2 Å to the crystal structure for well-defined regions, and RMSD value of 1.1 Å to crystal structure for core, non-solvent exposed sidechain atoms. Cross validation of the structure with 15N- and 13C-edited NOESY data obtained with a perdeuterated 15N, 13C-enriched 13CH3 methyl protonated CspA sample confirms that essentially all of these independently-interpreted NOE-based constraints are already satisfied in each of the 10 CS-Rosetta structures. By these criteria, the CS-Rosetta structure generated by fully automated analysis of data for a perdeuterated sample provides an accurate structure of CspA. This represents a general approach for rapid, automated structure determination of small proteins by NMR.

The guest–host interaction energy (GHIE) is often used as a predictor of the tendency of organic structure-directing agents (OSDAs) to promote the crystallization of a particular zeolite topology. Here, we explore the reliability of the GHIE to predict OSDA preferences for CHA versus AEI, chosen because they have similar pore volumes, are constructed from the same secondary building units, perform similar chemistries, and are crystallized by similar OSDAs. We show that predictions are sensitive to the choice of energy model and sampling method for some sets of OSDAs. We explore a set of secondary descriptors derived from the OSDA molecular size and shape and show that a combination of GHIE and the asymmetry index provides the most robust predictions.

Background: Huntington’s disease (HD) is characterized by a loss of control of motor function that causes the presence of abnormal eye movements at early stages.Objective: To determine if, compared to normal sheep, HD sheep have abnormal eye movements.Methods: We measured eye movements in a transgenic sheep (Ovis aries)model of HD using a purpose-built, head-mounted sheep oculometer. This allows us to measure saccades without the need for either behavioral training or head fixation. At the age of testing (6 years old), the HD sheep were pre-manifest. We used 21 sheep (11 HD, 10 normal).Results: We found small but significant differences in eye movements between normal (control) and HD sheep during vestibular ocular reflex (VOR)- and vestibular post-rotational nystagmus (PRN)-based tests.Conclusions: Two measures were identified that could distinguish normal from HD sheep; the number of PRN oscillations when tested in the dark and the gain (eye movement to head movement ratio) during the VOR when tested in the light. To our knowledge, this is the first study in which eye movements have been quantified in sheep. It demonstrates the feasibility of measuring and quantifying human-relevant eye movements in this species. The HD-relevant deficits show that even in ‘premanifest’ sheep there are measurable signs of neurological dysfunction that are characterized by loss of control of eye movements.

WHEN I DEMONSTRATE MY PASTEL APPROACH during a workshop, a student inevitably will say to me with great consternation, 'I took a workshop from so and so, and he/she told [...]

It's not Gasoline- Engine Car and Driver, it's Car and Driver. Former Lexus boss and new Toyota CEO Koji Sato has said he's considering a manual for the future Lexus electric supercar, and the company has a working prototype of such a thing in an electric Lexus UX. I'm so tired of all the letters complaining about Car and Driver's coverage of battery-electrics. Having owned literally hundreds of cars over the last 50 years, I can justifiably consider myself a car enthusiast. [Extracted from the article]

The arrangement of Al heteroatoms in zeolite frameworks influences turnover rates of Brønsted acid-catalyzed reactions and the speciation of exchanged metal cations and complexes that are active sites for redox catalysis. The substitution of Al for Si in zeolite frameworks generates anionic lattice charges and is thus influenced by the structure and charge density of the cationic structure directing agents (SDAs) that guide zeolite crystallization. Here, we investigate how framework Al structure and arrangements in chabazite (CHA) zeolites evolve as a function of hydrothermal treatment time as amorphous Al and Si precursors convert into partially and fully crystalline aluminosilicate phases in the presence of organic and inorganic SDAs. With N,N,N-trimethyl-1-adamantylammonium (TMAda+) as the sole SDA, an amorphous aluminosilicate network initially forms that contains a large fraction of proximal Al sites, as quantified by Co2+titration, which evolves into CHA crystallites that contain a high fraction of proximal Al sites in six-membered rings (6-MR). After bulk crystallization has been completed (433 K, 36 h), continued hydrothermal treatment causes rearrangement of framework Al to become more site-isolated, eventually resulting in CHA crystallites with undetectable numbers of 6-MR paired Al sites (433 K, 144 h). These temporal changes in framework Al arrangement indicate that Si–O–Al linkages remain labile and undergo restructuring within crystalline domains under hydrothermal conditions, allowing for atomic rearrangement toward thermodynamically preferred framework Al distributions (e.g., 6-MR isolated Al sites in the presence of TMAda+only). Ab initio molecular dynamics (AIMD) simulations report isolated Al configurations to be lower in energy than 6-MR Al pair configurations in a field of TMAda+, supporting a thermodynamic driving force for Al sites to isolate when TMAda+is the sole SDA. In contrast, using both Na+and TMAda+as inorganic and organic co-SDAs did not result in any further changes to the framework Al arrangement after CHA crystallization was complete (433 K, 96 h), suggesting that the co-occlusion of Na+and TMAda+suppresses the lability of framework Si–O–Al bonds and Al rearrangement in crystalline phases. AIMD simulations report 6-MR paired Al sites to become lower in energy than isolated Al configurations when charge-balanced by both Na+and TMAda+. These findings indicate that Al arrangements in zeolite frameworks can evolve upon extended hydrothermal treatment after bulk crystallization has been completed from amorphous Si and Al precursors and that such evolution is influenced by thermodynamic factors, extending prior reports of such phenomena occurring during interzeolite conversion routes.

Supercell density functional theory (DFT) calculations are used to create and exercise complete ethane dehydrogenation (EDH) reaction networks over Ni(111) and Ni2P(001). EDH intermediates are predicted to be more weakly bound to Ni2P than to Ni, with the differences being the greatest for deeply dehydrogenated intermediates. Both C–H and C–C bond cleavage activation energies are generally greater on Ni2P than Ni. The implications of these differences are explored through microkinetic models that incorporate a pathway for carbon growth. Ethylene formation rates and selectivities are predicted to be greater over Ni2P than Ni across a wide range of temperatures. Ni is predicted to be more susceptible to coke generation. Ethane activation exerts the greatest degree of rate control on both materials; in contrast, the competition between ethylene desorption and dehydrogenation controls selectivity on Ni, while no single step dominates selectivity on Ni2P. Results are consistent with previously reported observations, highlight the distinct and active contributions of phosphorus to phosphide surface chemistry, and highlight the role of coking pathways on predicted kinetics.

The mouth is the second most expressive feature on the human face after the eyes, but artists find it to be one of the most challenging features to represent accurately [...]

Management ideas sometimes fail for the following reasons: the social dynamics within organizations; the strength of cultural ideas; and the inappropriate selection and use of system interventions.

There are multiple components of a public health approach for preventing child maltreatment. One of these components is the question of who to intervene with. Fathers are an under-targeted and under-studied group for child maltreatment prevention. In this conceptual article, we describe a public health approach for intervening with fathers. Acknowledging financial stress as a key risk factor for child maltreatment among fathers, we explore two policy interventions that aim to increase economic support for families during the early years of a child’s life: paid family leave and child care subsidies. During the weeks following the child’s birth, paid family leave can promote child-father bonding and enable fathers to engage in more caregiving during a critical family transition. After paid family leave ends, child care subsidies can make child care affordable for families with low income, thereby promoting parents’ employment and earnings. We conclude by highlighting ways in which fathers can take an active role in preventing child maltreatment.

Metal phosphides are promising catalysts for hydrocarbon transformations, but computational screening is complicated by their diverse structures and compositions. To disentangle structural from compositional contributions, here we explore the metal-rich M2P (M = Fe, Co, Ni, Cu, Mo, Ru, Rh, Pd, Ag, Pt) series in hexagonal and orthorhombic structures that are common to a subset of these materials, using supercell density functional theory (DFT). To understand the contribution of metal choice to utility for catalytic ethane dehydrogenation (EDH), we compute and compare the adsorption of key EDH intermediates across low-index surface terminations. These materials expose both metal and phosphide sites. Calculations show that binding energies at metal sites correlate with the bulk metals, with P incorporation either enhancing or suppressing binding. Phosphide sites compete with metal sites for adsorbates and tend to suppress overactivation by destabilizing highly dehydrogenated species engaging in C–H bond breaking. Results are generally insensitive to bulk structure and surface facet. Results suggest metal-rich Pd phosphides to have favorable adsorption characteristics for catalytic dehydrogenation, consistent with recent observations.

Adsorption free energies are fundamental to surface chemistry and catalysis. Standard models combine some assumed analytical form of the translational potential energy surface, often parametrized against density functional theory (DFT) calculations, with an analytical expression for the resultant translational densities of states (DOS), free energy, and entropy. Here we compare the performance of such models against numerical evaluations of the DOS and thermodynamic functions derived from solutions to the translational Schrödinger equation. We compare results for a translational potential energy surface (PES) derived from nudged eleastic band calculations with those obtained from adsorbate rastering across a series of monatomic (O, S, C, N, and H) and polyatomic (NHx) adsorbates on (100) Pt and Au facets. We find that analytical models as commonly parametrized have mixed performance for describing the translational PES and that the consequences for computed free energies are modest but potentially significant in microkinetic models. Numerical solutions are possible for modest to no additional computational cost over analytical models and thus should be considered when reliable free energy estimates are needed or translational potential energy surfaces are available.

Immobilization of single metal atoms on a solid host opens numerous possibilities for catalyst designs. If that host is a two-dimensional sheet, sheet curvature becomes a design parameter potentially complementary to host and metal composition. Here, we use a combination of density functional theory calculations and microkinetic modeling to compare the mechanisms and kinetics of formic acid decomposition and formation, chosen for their relevance as a potential hydrogen storage medium, over single Ru atoms anchored to pyridinic nitrogen in a planar graphene flake (RuN4-G) and curved carbon nanotube (RuN4-CNT). Activation barriers are lowered and the predicted turnover frequencies are increased over RuN4-CNT relative to RuN4-G. The results highlight the potential of curvature control as a means to achieve high performance and robust catalysts.

The 'Perot 19' control the politics of this historical moment: any hope the Democrats have of building a new presidential majority rests on them, as does any hope of the [...]

The United States is a nation of suburbs. The 1990 census makes it official. Nearly half the country's population now lives in suburbs, up from a quarter in 1950 and [...]

GEORGE BUSH was elected President in 1988 because most American voters were satisfied with the status quo. What we got is a status-quo President. So far, the status quo has [...]

The purpose of this study was to determine the incidence of clinically significant postoperative stiffness after arthroscopic rotator cuff repair and its resolution. The study also sought to determine clinical and surgical factors that may be associated with increased rates of postoperative stiffness.

Forty-eight percent of Americans surveyed at end-July 1998 would prefer to believe Monica Lewinsky if she claimed to an extramarital affair with US President Bill Clinton, with just forty-four percent claiming they would prefer to believe Clinton's denial. Forty-nine percent claimed they would believe Clinton if he denied asking Lewinsky to lie under oath, with forty-four percent claiming they would believe Lewinsky if she claimed he asked her to lie. Further US public opinion of Clinton and Lewinsky is presented.

Copper-exchanged chabazite (Cu-CHA) zeolites are catalysts used in diesel emissions control for the abatement of nitrogen oxides (NOx) via selective catalytic reduction (SCR) reactions with ammonia as the reductant. The discovery of these materials in the early 2010s enabled a step-change improvement in diesel emissions aftertreatment technology. Key advantages of Cu-CHA zeolites over prior materials include their effectiveness at the lower temperatures characteristic of diesel exhaust, their durability under high-temperature hydrothermal conditions, and their resistance to poisoning from residual hydrocarbons present in exhaust. Fundamental catalysis research has since uncovered mechanistic and kinetic features that underpin the ability of Cu-CHA to selectively reduce NOxunder strongly oxidizing conditions and to achieve improved NOxconversion relative to other zeolite frameworks, particularly at low exhaust temperatures and with ammonia instead of other reductants.

We investigated the influence of P incorporation into a Ni catalyst on ethane dehydrogenation (EDH). Density functional theory calculations on model Ni(111) and Ni2P(001) surfaces reveal that surface P generally decreases adsorption energies of fragments relevant to EDH at surface Ni sites but that P itself participates in binding some of these intermediates. These nonlinear influences of P cause CH3CH2–H activation to occur with similar facility on metal and phosphide surfaces, while CH2CH–H activation, an indicator of coking tendency, has much greater barriers on the phosphide. We prepared Ni and Ni–P catalysts on an SBA-15 support to test these predictions. A Ni–P catalyst with a 2:1 ratio (Ni2P(2)/SBA-15), corresponding to the Ni2P phase, showed >80% ethylene selectivity during EDH at 873 K, compared to <1% ethylene selectivity on Ni/SBA-15, and maintained this selectivity up to 4 h time-on-stream. Diffuse reflectance infrared Fourier transform spectroscopy observations following ethylene exposure and heating under an inert flow indicate the appearance of carbon deposits on Ni/SBA-15 compared to ethylene desorption from Ni2P(2)/SBA-15, consistent with predicted adsorption energy trends. Thermogravimetric analysis of spent EDH catalysts indicates significantly less carbon deposition on Ni2P(2)/SBA-15 relative to Ni/SBA-15. The results highlight the potential of metal phosphides as selective and robust alkane dehydrogenation catalysts.

On the wall of his art studio, artist Dan Gerhartz has a pencil drawing of an eye originally painted by Nicolai Fechin. Zorn used ivory black, yellow ochre, vermilion and white to create most of his masterworks. DEMO: After Zorn, Coquelin Cadet In this demo, my goal was to learn from the work of Anders Zorn (Swedish, 1860-1920) - specifically his painting, Coquelin Cadet (below). [Extracted from the article]

We combine experiment and theory to investigate the cooperation or competition between organic and inorganic structure-directing agents (SDAs) for occupancy within microporous voids of chabazite (CHA) zeolites and to rationalize the effects of SDA siting on biasing the framework Al arrangement (Al–O(−Si–O)x–Al, x= 1–3) among CHA zeolites of essentially fixed composition (Si/Al = 15). CHA zeolites crystallized using mixtures of TMAda+and Na+contain one TMAda+occluded per cage and Na+co-occluded in an amount linearly proportional to the number of 6-MR paired Al sites, quantified by Co2+titration. In contrast, CHA zeolites crystallized using mixtures of TMAda+and K+provide evidence that three K+cations, on average, displace one TMAda+from occupying a cage and contain predominantly 6-MR isolated Al sites. Moreover, CHA crystallizes from synthesis media containing more than 10-fold higher inorganic-to-organic ratios with K+than with Na+before competing crystalline phases form, providing a route to decrease the amount of organic SDA needed to crystallize high-silica CHA. Density functional theory calculations show that differences in the ionic radii of Na+and K+determine their preferences for siting in different CHA rings, which influences their energy to co-occlude with TMAda+and stabilize different Al configurations. Monte Carlo models confirm that energy differences resulting from Na+or K+co-occlusion promote the formation of 6-MR and 8-MR paired Al arrangements, respectively. These results highlight opportunities to exploit using mixtures of organic and inorganic SDAs during zeolite crystallization in order to more efficiently use organic SDAs and influence framework Al arrangements.

The binding energies of adsorbates at catalytic surfaces are in general functions of adsorbate coverage, with corresponding consequences for equilibrium surface coverages and reaction rates under relevant conditions. This coverage dependence is commonly incorporated into mean-field microkinetic models by writing adsorption energies as an algebraic function of coverage and parametrizing against density functional theory models. In this work, we compare the performance of three different analytical coverage-dependent forms, including linear and piecewise models and a logarithmic form inspired by Wilson’s activity model, against accurate results obtained from a lattice-based cluster expansion (CE) representation of adsorbate interactions combined with a Monte Carlo evaluation of reaction rates. We take as a model system O2dissociation-limited NO oxidation to NO2over Pt(111), parametrize all models against the same set of previously reported coverage-dependent NO and O binding energies, and solve kinetic models under the same set of assumptions. Steady-state coverages from the analytical models are similar to each other and the ensemble-averaged CE result, other than the discontinuities in O and NO coverages that appear in the piecewise model. Predicted steady-state rates differ more substantially, reflecting the sensitivity of the O2dissociation activation energy to coverage-dependent binding energies. The activity model predicts reaction rates reliably at low temperatures and systematically deviates from CE rates at high temperatures, where minority surface sites, having low local coverage around vacant pairs, dominate overall reaction rates. The results highlight the challenges of developing coverage-dependent microkinetic models that are reliable across a range of conditions.

The Earth's magnetic field is used as a navigational cue by many animals. For mammals, however, there are few data to show that navigation ability relies on sensing the natural magnetic field. In night-time migrating bats, experiments demonstrating a role for the solar azimuth at sunset in the calibration of the orientation system suggest that the magnetic field is a candidate for their compass. Here, we investigated how an altered magnetic field at sunset changes the nocturnal orientation of the bat Pipistrellus pygmaeus. We exposed bats to either the natural magnetic field, a horizontally shifted field (120°), or the same shifted field combined with a reversal of the natural value of inclination (70° to −70°). We later released the bats and found that the take-off orientation differed among all treatments. Bats that were exposed to the 120° shift were unimodally oriented northwards in contrast to controls which exhibited a bimodal north–south distribution. Surprisingly, the orientation of bats exposed to both a 120° shift and reverse inclination was indistinguishable from a uniform distribution. These results suggest that these migratory bats calibrate the magnetic field at sunset, and for the first time, they show that bats are sensitive to the angle of magnetic inclination.

'I AM PLEASED with the Supreme Court's decision,' President George Bush said in a written statement released after the Court issued its ruling in Planned Parenthood of Southeastern Pennsylvania v. [...]