Multilaminate Energy Storage Films from Entropy-Driven Self-Assembled Supramolecular Nanocomposites.

Composite materials comprising polymers and inorganic nanoparticles (NPs) are promising for energy storage applications, though challenges in controlling NP dispersion often result in performance bottlenecks. Realizing nanocomposites with controlled NP locations and distributions within polymer microdomains is highly desirable for improving energy storage capabilities but is a persistent challenge, impeding the in-depth understanding of the structure-performance relationship. In this study, a facile entropy-driven self-assembly approach is employed to fabricate block copolymer-based supramolecular nanocomposite films with highly ordered lamellar structures, which are then used in electrostatic film capacitors. The oriented interfacial barriers and well-distributed inorganic NPs within the self-assembled multilaminate nanocomposites effectively suppress leakage current and mitigate the risk of breakdown, showing superior dielectric strength compared to their disordered counterparts. Consequently, the lamellar nanocomposite films with optimized composition exhibit high energy efficiency (>90% at 650 MV m-1), along with remarkable energy density and power density. Moreover, finite element simulations and statistical modeling have provided theoretical insights into the impact of the lamellar structure on electrical conduction, electric field distribution, and electrical tree propagation. This work marks a significant advancement in the design of organic-inorganic hybrids for energy storage, establishing a well-defined correlation between microstructure and performance.

High-performing polysulfate dielectrics for electrostatic energy storage under harsh conditions.

High capacity polymer dielectrics that operate with high efficiencies under harsh electrification conditions are essential components for advanced electronics and power systems. It is, however, fundamentally challenging to design polymer dielectrics that can reliably withstand demanding temperatures and electric fields, which necessitate the balance of key electronic, electrical and thermal parameters. Herein, we demonstrate that polysulfates, synthesized by sulfur(VI) fluoride exchange (SuFEx) catalysis, another near-perfect click chemistry reaction, serve as high-performing dielectric polymers that overcome such bottlenecks. Free-standing polysulfate thin films from convenient solution processes exhibit superior insulating properties and dielectric stability at elevated temperatures, which are further enhanced when ultrathin (~5 nm) oxide coatings are deposited by atomic layer deposition. The corresponding electrostatic film capacitors display high breakdown strength (>700 MV m-1) and discharged energy density of 8.64 J cm-3 at 150 °C, outperforming state-of-the-art free-standing capacitor films based on commercial and synthetic dielectric polymers and nanocomposites.

Parental Guidance Required: How Parents Could Help Reduce the Shortage of Minority Physician Assistants.

Physician assistants (PAs) are essential to the health care system, and there are not nearly enough of them to meet the needs of our ethnically diverse population. Factors contributing to a lack of minorities in PA schools are related to academic performance, commitments outside work/school, and social and economic deprivation. From 2014 to 2016, the Texas Area Health Education Center East worked with the University of Texas Medical Branch at Galveston to implement Physician Assistant Learner Support programming. This program, targeting minority high school students, promoted and educated both students and parents about PA careers with the objective of alleviating one of the main barriers to minority higher education-lack of understanding of educational and career opportunities. This study found that parental knowledge about PA application requirements, PA degree requirements, financial aid, and career prospects at the high school level is essential to securing parental support of student selection of PA careers.

Improving Primary Care Retention in Medically Underserved Areas: What's a Clinic to Do?

To reduce health professional shortage areas, the National Health Service Corps has attempted to increase the number of primary care providers in underserved communities through scholarships and loan repayment. Program evaluations assessed Loan Repayment Program (LRP) propensity to work in underserved communities. The National Health Service Corps LRPs were asked about preferences for particular retention strategies and which strategies were utilized by their clinical sites. Loan Repayment Programs were asked to rank retention strategies. Loan Repayment Program top choices were competitive salary, 88%; professional development, 70%; knowledgeable/competent support staff, 59%, and professional support, 58%. Loan Repayment Programs were also asked to rank retention strategies provided by their clinical sites: professional development, 74.2%; competitive salary, 71.2%; policies that prohibit abusive behavior, 63.6%, and knowledgeable/competent support staff, 60.6%. Loan Repayment Programs indicated professional support was an important retention element. However, when asked if professional support opportunities were offered, LRP indicated that these were not in the strategies offered by sites.

Solution-processable triindoles as hole selective materials in organic solar cells.

We report the use of two solution-processable triindoles, triazatruxene (TAT), and N-trimethyltriindole (TMTI), as hole selective materials in organic solar cells. The unique optical and electronic properties of these molecules make them suitable as a hole extracting/electron blocking layer, i.e. transparency in the visible region due to a wide bandgap, high LUMO (lowest unoccupied molecular orbital) energy level, modest HOMO (highest occupied molecular orbital) level, and high hole carrier mobility. TAT is shown to have a LUMO at -1.68 eV, a HOMO at -5.03 eV, and a bandgap of 3.35 eV, whereas TMTI has a LUMO at -2.05 eV, a HOMO at -5.1 eV, and a bandgap of 3.05 eV, obtained from cyclic voltammetry measurements and absorption spectroscopy. Planar heterojunction photovoltaic devices, consisting of a solution processed transparent TAT (or TMTI) layer and a vapor-deposited C60 layer, exhibited efficiencies of up to 0.71 % (or 0.87 %). In these bilayer devices, the excitons are primarily generated in the C60 layer and undergo dissociation in the interfaces via hole transfer from the C60 layer to the TAT (or TMTI) layer. Additionally, spin-casting methanol solution of TAT on the top of P3HT:PCBM bulk heterojunction in an inverted device produced a hole selective interfacial layer between the photoactive layer and anode, leading to a 26% efficiency increase as compared to a control device without the TAT layer.

Oligo- and polythiophene/ZnO hybrid nanowire solar cells.

We demonstrate the basic operation of an organic/inorganic hybrid single nanowire solar cell. End-functionalized oligo- and polythiophenes were grafted onto ZnO nanowires to produce p-n heterojunction nanowires. The hybrid nanostructures were characterized via absorption and electron microscopy to determine the optoelectronic properties and to probe the morphology at the organic/inorganic interface. Individual nanowire solar cell devices exhibited well-resolved characteristics with efficiencies as high as 0.036%, J(sc) = 0.32 mA/cm(2), V(oc) = 0.4 V, and a FF = 0.28 under AM 1.5 illumination with 100 mW/cm(2) light intensity. These individual test structures will enable detailed analysis to be carried out in areas that have been difficult to study in bulk heterojunction devices.

Creating a positive work environment: implementation of the nurse-friendly hospital criteria.

The nursing shortage is negatively affecting the quality, effectiveness, and timeliness of patient care, which warrants a transformation of the nursing work environment. The Nurse-Friendly (NF) Hospital Project assisted 30 rural or small hospitals implement 12 NF criteria into hospital policies to create a positive work environment. The NF criteria represent organizational attributes necessary for ensuring quality patient care, positive work environment, professional development, and nurse satisfaction. The authors discuss nurses' perception of presence of NF criteria before and after they were incorporated at each hospital and the implementation outcomes.

The distribution of D2/D3 receptor binding in the adolescent rhesus monkey using small animal PET imaging.

UNLABELLED: PET imaging of the neuroreceptor systems in the brain has earned a prominent role in studying normal development, neuropsychiatric illness and developing targeted drugs. The dopaminergic system is of particular interest due to its role in the development of cognitive function and mood as well as its suspected involvement in neuropsychiatric illness. Nonhuman primate animal models provide a valuable resource for relating neurochemical changes to behavior. To facilitate comparison within and between primate models, we report in vivo D2/D3 binding in a large cohort of adolescent rhesus monkeys. METHODS: In this work, the in vivo D2/D3 dopamine receptor availability was measured in a cohort of 33 rhesus monkeys in the adolescent stage of development (3.2-5.3 years). Both striatal and extrastriatal D2/D3 binding were measured using [F-18]fallypride with a high resolution small animal PET scanner. The distribution volume ratio (DVR) was measured for all subjects and group comparisons of D2/D3 binding among the cohort were made based on age and sex. Because two sequential studies were acquired from a single [F-18]fallypride batch, the effect of competing (unlabeled) ligand mass was also investigated. RESULTS: Among this cohort, the rank order of regional D2/D3 receptor binding did not vary from previous studies with adult rhesus monkeys, with: putamen>caudate>ventral striatum>amygdala approximately substantia nigra>medial dorsal thalamus>lateral temporal cortex approximately frontal cortex. The DVR coefficient of variation ranged from 14%-26%, with the greatest variance seen in the head of the caudate. There were significant sex differences in [F-18]fallypride kinetics in the pituitary gland, but this was not observed for regions within the blood-brain barrier. Furthermore, no regions in the brain showed significant sex or age related differences in DVR within this small age range. Based on a wide range of injected fallypride mass across the cohort, significant competition effects could only be detected in the substantia nigra, thalamus, and frontal cortex, and were not evident above intersubject variability in all other regions. CONCLUSION: These data represent the first report of large cohort in vivo D2/D3 dopamine whole brain binding in the adolescent brain and will serve as a valuable comparison for understanding dopamine changes during this critical time of development and provide a framework for creating a dopaminergic biochemical atlas for the rhesus monkey.

Nurse-Friendly Hospital Project: enhancing nurse retention and quality of care.

The present shortage of nurses in the United States is expected to continue. Nurse shortage, the nature of the work environment, and employers' expectations and attitudes, among other factors, influence both nurse retention and quality of patient care. The Nurse-Friendly Hospital Project was designed to improve nurses' work environment in rural and small hospitals in Texas. Findings demonstrate improvements in nurse retention, nurse staffing, and quality of care.