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Thermoelectric materials with high electrical conductivity and low thermal conductivity (e.g., Bi2Te3) can efficiently convert waste heat into electricity; however, in spite of favorable theoretical predictions, individual Bi2Te3 nanostructures tend to perform less efficiently than bulk Bi2Te3. We report a greater-than-order-of-magnitude enhancement in the thermoelectric properties of suspended Bi2Te3 nanoribbons, coated in situ to form a Bi2Te3/F4-TCNQ core-shell nanoribbon without oxidizing the core-shell interface. The shell serves as an oxidation barrier but also directly functions as a strong electron acceptor and p-type carrier donor, switching the majority carriers from a dominant n-type carrier concentration (∼1021 cm-3) to a dominant p-type carrier concentration (∼1020 cm-3). Compared to uncoated Bi2Te3 nanoribbons, our Bi2Te3/F4-TCNQ core-shell nanoribbon demonstrates an effective chemical potential dramatically shifted toward the valence band (by 300-640 meV), robustly increased Seebeck coefficient (∼6× at 250 K), and improved thermoelectric performance (10-20× at 250 K).

Using four-dimensional scanning transmission electron microscopy, we demonstrate a method to visualize grains and grain boundaries in WSe2 grown by metal organic chemical vapor deposition (MOCVD) directly onto silicon dioxide. Despite the chemical purity and uniform thickness and texture of the MOCVD-grown WSe2, we observe a high density of small grains that corresponds with the overall selenium deficiency we measure through ion beam analysis. Moreover, reconstruction of grain information permits the creation of orientation maps that demonstrate the nucleation mechanism for new layers-triangular domains with the same orientation as the layer underneath induces a tensile strain increasing the lattice parameter at these sites.

ObjectiveThis study examined the extent to which prehospital treatment engagement is related to posthospital follow-up treatment among psychiatric inpatients and whether the effects of inpatient discharge planning on posthospital follow-up treatment vary by level of pretreatment engagement in care.MethodsNew York State Medicaid and other administrative databases were used to examine service use by 18,793 adult patients discharged to the community after inpatient psychiatric care in 2012-2013. Outcomes included attending an outpatient mental health service within 7 days and within 30 days after discharge. The sample was stratified by whether patients had high, partial, low, or no engagement in outpatient psychiatric services in the 6 months before admission.ResultsScheduling an outpatient appointment as part of the patient's discharge plan was significantly associated with attending outpatient psychiatric appointments, regardless of the patient's level of engagement in care before admission. The differences were most pronounced for patients who had not received any outpatient care in the 6 months before admission. When an appointment was scheduled, these patients were three times more likely to follow up with care within 7 days and more than twice as likely to follow up within 30 days than were patients without a scheduled appointment.ConclusionsThe likelihood of psychiatric inpatients following up with outpatient psychiatric care was directly related to their level of outpatient care engagement before hospital admission. Even among those who had not been engaged in outpatient care, inpatient discharge planning was associated with a greater likelihood of receiving follow-up outpatient care.

Scanning transmission electron microscopy (STEM) allows for imaging, diffraction, and spectroscopy of materials on length scales ranging from microns to atoms. By using a high-speed, direct electron detector, it is now possible to record a full two-dimensional (2D) image of the diffracted electron beam at each probe position, typically a 2D grid of probe positions. These 4D-STEM datasets are rich in information, including signatures of the local structure, orientation, deformation, electromagnetic fields, and other sample-dependent properties. However, extracting this information requires complex analysis pipelines that include data wrangling, calibration, analysis, and visualization, all while maintaining robustness against imaging distortions and artifacts. In this paper, we present py4DSTEM, an analysis toolkit for measuring material properties from 4D-STEM datasets, written in the Python language and released with an open-source license. We describe the algorithmic steps for dataset calibration and various 4D-STEM property measurements in detail and present results from several experimental datasets. We also implement a simple and universal file format appropriate for electron microscopy data in py4DSTEM, which uses the open-source HDF5 standard. We hope this tool will benefit the research community and help improve the standards for data and computational methods in electron microscopy, and we invite the community to contribute to this ongoing project.

ObjectiveShortened life expectancy of people with mental disorders has been attributed to medical comorbidities, yet these conditions remain under-recognized and under-treated. This study characterizes the medical demands placed on inpatient psychiatric units to help guide medical assessment and management practices in these settings.MethodsMedicaid claims records and clinician data were linked with hospital and regional data for individuals with a principal diagnosis of any mental disorder admitted to psychiatric inpatient units in New York State from 2012 to 2013. A modified Elixhauser Comorbidity Index (ECI) score was calculated for each unique individual (n = 14,458). Adjusted odds ratios (AORs) of having a medical comorbidity were calculated using logistic regression analyses.Results74.9% of psychiatric inpatients had at least one medical comorbidity, including 57.5% of people ages 18-24. Higher rates of medical comorbidity were associated with older age, female gender, non-schizophrenia diagnoses, and engagement in care prior to hospitalization. Patients with medical comorbidities had lower odds (AOR 0.54; 99% CI 0.35-0.83) of being treated in hospitals with 100 or more total beds compared to smaller hospitals.ConclusionsA high prevalence of common medical diagnoses among psychiatric inpatients underscores the importance of adequate detection and medical treatment of medical comorbidities in psychiatric inpatient settings.

Developing novel lead‐free ferroelectric materials is crucial for next‐generation microelectronic technologies that are energy efficient and environment friendly. However, materials discovery and property optimization are typically time‐consuming due to the limited throughput of traditional synthesis methods. In this work, we use a high‐throughput combinatorial synthesis approach to fabricate lead‐free ferroelectric superlattices and solid solutions of (Ba0.7Ca0.3)TiO3 (BCT) and Ba(Zr0.2Ti0.8)O3 (BZT) phases with continuous variation of composition and layer thickness. High‐resolution x‐ray diffraction (XRD) and analytical scanning transmission electron microscopy (STEM) demonstrate high film quality and well‐controlled compositional gradients. Ferroelectric and dielectric property measurements identify the "optimal property point" achieved at the composition of 48BZT–52BCT. Displacement vector maps reveal that ferroelectric domain sizes are tunable by varying {BCT–BZT}N superlattice geometry. This high‐throughput synthesis approach can be applied to many other material systems to expedite new materials discovery and properties optimization, allowing for the exploration of a large area of phase space within a single growth. [ABSTRACT FROM AUTHOR]

The focus of this work is on the nano-scale characterization of transition metal oxides employed as carrier selective contacts in crystalline silicon (c-Si) solar cells using crosssectional transmission electron microscopy (TEM). Both electronselective (titanium dioxide, TiO 2 ) and hole-selective (molybdenum oxide, MoO x ; tungsten oxide, WO x textbf) contacts were investigated. High-resolution TEM (HRTEM) images were obtained with a FEI Tecnai F30 TEM.

Plaintiffs in securities class actions have increasingly relied on reports published by anonymous short sellers when alleging the element of loss causation. Indeed, short-seller reports are useful for plaintiffs, as they purport to reveal negative information about a targeted company and generally cause a decline in the targeted company's stock price. Unlike other types of corrective disclosures, however, short-seller reports are unique in that they are written by self-interested parties who benefit financially from driving down stock prices. For that reason, short-seller reports are potential tools for stock-price manipulation. This Note, addressing a recent circuit split on this issue, argues that courts should require more from plaintiffs who rely on short-seller reports for their complaints' loss causation allegations. In particular, this Note advocates for the judicial assessment of certain facts available at pleading-- namely, price reversals, short-seller reputation, and corroborative corrective disclosures--when courts consider a motion to dismiss in cases that rely on revelations contained in short-seller reports. In doing so, courts can reduce burdensome litigation based on manipulative reports while enabling the compensation of genuinely defrauded plaintiffs. [ABSTRACT FROM AUTHOR]

Many contemporary Anglophone Caribbean writers resent their colonial education’s emphasis on British literature, especially Wordsworth’s “Daffodils” poem, which—as V.S. Naipaul, Marlene NourbeSe Philip, Jean Rhys, and Jamaica Kincaid complain—impelled them to admire a flower they had never seen. This essay explores the resentful aesthetics spurred by “the daffodil gap,” a critical trope reflecting the disconnect between colonial education and lived experience. Multicultural literature’s and criticism’s emphasis on “decolonizing the curriculum” encourages the resentful denigration of classic and beloved texts. This essay also employs a close reading of “I wandered lonely as a cloud” to demonstrate how an aesthetics of resentment misconstrues Wordsworth’s poem, which explores human consciousness rather than simply celebrating the beauty of a particular European flower. [ABSTRACT FROM AUTHOR]