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We report a photovoltaic effect in ferroelectric BiFeO3 thin films. The all-oxide heterostructures with SrRuO3 bottom and tin doped indium oxide top electrodes are characterized by open-circuit voltages ∼0.8–0.9 V and external quantum efficiencies up to ∼10% when illuminated with the appropriate light. Efficiencies are at least an order of magnitude larger than the maximum efficiency under sunlight (AM 1.5) thus far reported for ferroelectric-based devices. The dependence of the measured open-circuit voltage on film thickness suggests contributions to the large open-circuit voltage from both the ferroelectric polarization and band offsets at the BiFeO3/tin doped indium oxide interface. [ABSTRACT FROM AUTHOR]

Background Appropriate Use Criteria (AUC) for echocardiography are a useful tool to deliver quality healthcare. Our quality-based interventional study was designed to assess the trends in appropriate utilization rates for echocardiography in our institution and improve adherence to the AUC criteria for transthoracic echocardiograms (TTE). Methodology A prospective, time series analysis was conducted at the Upstate University Hospital for the months of July 2019 and August 2020. A chart analysis was performed on 620 consecutive inpatients who underwent TTE for the month of July 2019. We assessed the trends of the appropriate ordering of TTEs. We then updated our order form incorporating the 42 most common appropriate indications. A post-intervention chart analysis was performed on all inpatient TTEs ordered for the month of August 2020 (n = 410). The appropriateness of the TTE for the entire group was determined based on the true indication per chart review. The primary outcome was the proportion of appropriate and inappropriate TTEs ordered. Secondary outcomes included assessing for concordance between the indication on the order requisition form and by chart review. A p-value <0.05 was considered significant. Results Using the 2011 AUC for the entire group, 81% of the pre-intervention TTEs and 79.5% of the post-intervention TTEs were appropriate (p = 0.55). There was a statistically significant reduction in the number of discordant TTE orders before and after the intervention (p < 0.01). In addition, we noted increased appropriateness of TTEs in the concordant group both pre and post-intervention. Conclusions Our study demonstrates a significant increase in the concordance between the TTE order sheet and actual indication per chart review with the intervention. This can translate into improved scanning and physician reading quality and time, thereby increasing focus on areas of interest according to the true indication. There was no significant increase in the appropriate TTEs ordered., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Paulraj et al.)

Mitral valve prolapse (MVP) affects approximately 170 million people worldwide; however, phenotypically, there is a wide variety of heterogeneity. In particular subsets, the incidence of sudden cardiac death is calculated to be 998 per 100,000 person-years, which is significantly increased when compared with the general population of MVP patients. Individuals with high-risk features have been identified as young females with bileaflet MVP and electrocardiogram findings of frequent complex ectopy, ST-T wave changes, and inferior T wave inversions. Supplemental imaging modalities in this subgroup demonstrate redundant leaflets and chordae on 2-dimensional transthoracic echocardiography along with varying severity of mitral annular disjunction. Detailed morphologic assessment by 3-dimensional echocardiography provides a quantitative assessment of annular disjunction along with left ventricular longitudinal and basal circumferential strain patterns. Late gadolinium enhancement on cardiac magnetic resonance imaging identifies diffuse and isolated left ventricle fibrosis involving the fascicles and papillary muscles, which has been visualized in isolation during autopsy. Findings of this review propose that sudden cardiac death as a result of malignant arrhythmias arises from automaticity, complex ectopy, and reentry at the level of the fascicles and papillary muscles. The repetitive mechanical stress provides a nidus for the development of both micro- and macrofibrosis easily identified by late gadolinium enhancement on cardiac magnetic resonance imaging. Escalation to electrophysiology studies and early intervention could provide new targeted lifesaving therapies., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

HIV-associated neurocognitive disorders (HAND) are a leading cause of morbidity in up to 50% of individuals living with HIV, despite effective treatment with antiretroviral therapy (ART). Current evidence suggests that chronic inflammation associated with HIV is especially attributed to the dysregulated production of reactive oxygen species (ROS) that contribute to neurodegeneration and poor clinical outcomes. While ROS have beneficial effects in eliciting immune responses to infection, chronic ROS production causes damage to macromolecules such as DNA and lipids that has been linked to altered redox homeostasis associated with antioxidant dysregulation. As a result, this disruption in the balance between antioxidant-dependent mechanisms of ROS inactivation and ROS production by enzymes such as the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase family, as well as from the electron transport chain of the mitochondria can result in oxidative stress. This is particularly relevant to the brain, which is exquisitely susceptible to oxidative stress due to its inherently high lipid concentration and ROS levels that have been linked to many neurodegenerative diseases that have similar stages of pathogenesis to HAND. In this review, we discuss the possible role and mechanisms of ROS production leading to oxidative stress that underpin HAND pathogenesis even when HIV is suppressed by current gold-standard antiretroviral therapies. Furthermore, we highlight that pathological ROS can serve as biomarkers for HIV-dependent HAND, and how manipulation of oxidative stress and antioxidant-dependent pathways may facilitate novel strategies for HIV cure., Competing Interests: The authors declare that they have no competing interests., (© 2021 The Authors.)

Short-stay units are medical units with anticipated lengths of stay of 24-72 hours. The purpose of this study was to identify characteristics and predictors of 30-day readmission among patients admitted to a short-stay unit during two separate time periods. Findings suggest the presence of previous Emergency Department visits or hospitalizations should be considered when aligning discharge needs, as these may impact subsequent patient readmissions.

A series of ketocyanine derivatives possessing bis(diarylamino)fluorenyl donors and variable acceptors installed at the bridging carbon atom were synthesized to investigate how the electronic structure of the dye can be systemically tuned through stabilization of the cyanine-like character of the donor by increasing the acceptor strength. Analysis of the (1) H NMR spectra indicates that the "charge-separated" species dominates in these dyes, given that carbons possessing a positive or negative charge in the resonance structures of this state purposefully shift downfield or upfield, respectively, depending on the strength of the acceptor moiety. In DAA-Fl-PI, the acceptor strength and the gain of acceptor aromaticity indicates a predisposition of the separated state, indicated by asymmetry in the (1) H NMR spectrum, as well as uneven distribution of the HOMO on the fluorenyl donor., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: The global need for disease detection and control has increased effort to engineer point-of-care (POC) tests that are simple, robust, affordable, and non-instrumented. In many POC tests, sample collection involves swabbing the site (e.g., nose, skin), agitating the swab in a fluid to release the sample, and transferring the fluid to a device for analysis. Poor performance in sample transfer can reduce sensitivity and reproducibility., Methods: In this study, we compared bacterial release efficiency of seven swab types using manual-agitation methods typical of POC devices. Transfer efficiency was measured using quantitative PCR (qPCR) for Staphylococcus aureus under conditions representing a range of sampling scenarios: 1) spiking low-volume samples onto the swab, 2) submerging the swab in excess-volume samples, and 3) swabbing dried sample from a surface., Results: Excess-volume samples gave the expected recovery for most swabs (based on tip fluid capacity); a polyurethane swab showed enhanced recovery, suggesting an ability to accumulate organisms during sampling. Dry samples led to recovery of ∼20-30% for all swabs tested, suggesting that swab structure and volume is less important when organisms are applied to the outer swab surface. Low-volume samples led to the widest range of transfer efficiencies between swab types. Rayon swabs (63 µL capacity) performed well for excess-volume samples, but showed poor recovery for low-volume samples. Nylon (100 µL) and polyester swabs (27 µL) showed intermediate recovery for low-volume and excess-volume samples. Polyurethane swabs (16 µL) showed excellent recovery for all sample types. This work demonstrates that swab transfer efficiency can be affected by swab material, structure, and fluid capacity and details of the sample. Results and quantitative analysis methods from this study will assist POC assay developers in selecting appropriate swab types and transfer methods.

This Review focuses on recent work in the field of paper microfluidics that specifically addresses the goal of translating the multistep processes that are characteristic of gold-standard laboratory tests to low-resource point-of-care settings. A major challenge is to implement multistep processes with the robust fluid control required to achieve the necessary sensitivity and specificity of a given application in a user-friendly package that minimizes equipment. We review key work in the areas of fluidic controls for automation in paper-based devices, readout methods that minimize dedicated equipment, and power and heating methods that are compatible with low-resource point-of-care settings. We also highlight a focused set of recent applications and discuss future challenges.

Many new and exciting portable HIV viral load testing technologies are emerging for use in global medicine. While the potential to provide fast, isothermal, and quantitative molecular diagnostic information to clinicians in the field will soon be a reality, many of these technologies lack a robust front end for sample clean up and nucleic acid preparation. Such a technology would enable many different downstream molecular assays. Here, we present a portable system for centrifuge-free room temperature nucleic acid extraction from small volumes of whole blood (70 µL), using only thermally stable reagents compatible with storage and transport in low resource settings. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) analysis of simulated samples demonstrate a lower limit of detection of 1000 copies/ml, with the ability to detect differences in viral load across four orders of magnitude. The system can also be used to store extracted RNA on detachable cartridges for up to one week at ambient temperature, and can be operated using only hand generated air pressure.

Often, modern diagnostic techniques require the isolation and purification of nucleic acids directly from patient samples such as blood or stool. Many diagnostic tests are being miniaturized onto micro-sized platforms and integrated into microfluidic devices due to the economies resulting from smaller sample and reagent volumes. Often, these devices perform sample preparation in series with the diagnostic tests. The sample preparation steps are vital in order to purify the desired genetic material from potential inhibitors that can interfere with the outcome of the test. There are various techniques used to selectively capture the nucleic acids while washing away potential contamination (proteins, enzymes, lipids, etc.). Two of the most common forms of selective capture are based on nucleic acid binding to silica surface or on the precipitation of nucleic acids with or without the presence of a carrier species. Each of these methods can be performed in liquid phase or in a solid support such as an extraction column. Here we discuss both methods and address microfluidic applications.

Pulmonary lymphangioleiomyomatosis (LAM) is a rare cystic lung disease that targets women during their reproductive years. A confident diagnosis can often be based on clinical grounds, but diagnostic certainty requires pathological analysis. Although surgical lung biopsy is considered the gold standard for obtaining tissue in patients with diffuse lung disease, it is also associated with higher morbidity and mortality than alternative, less invasive techniques. The objective of our study was to examine the utility of transbronchial biopsy in the diagnosis of LAM. We conducted two online surveys of over 1,000 LAM patients registered with the LAM Foundation who were accessible by email. Transbronchial biopsy specimens were subsequently collected and reviewed by an expert pathologist to validate the diagnosis. We found that transbronchial biopsy has a yield of approximately 60% in patients with LAM. We conclude that transbronchial biopsy may be a safe and effective method for establishing the diagnosis of LAM, obviating the need for surgical lung biopsy in more than half of LAM patients.

Photovoltaics (PV) are a promising source of clean renewable energy, but current technologies face a cost-to-efficiency trade-off that has slowed widespread implementation. We have developed a PV architecture-screening-engineered field-effect photovoltaics (SFPV)-that in principle enables fabrication of low-cost, high efficiency PV from virtually any semiconductor, including the promising but hard-to-dope metal oxides, sulfides, and phosphides. Prototype SFPV devices have been constructed and are found to operate successfully in accord with model predictions.

Background: Understanding the true prevalence of lymphangioleiomyomatosis (LAM) is important in estimating disease burden and targeting specific interventions. As with all rare diseases, obtaining reliable epidemiological data is difficult and requires innovative approaches., Aim: To determine the prevalence and incidence of LAM using data from patient organizations in seven countries, and to use the extent to which the prevalence of LAM varies regionally and nationally to determine whether prevalence estimates are related to health-care provision., Methods: Numbers of women with LAM were obtained from patient groups and national databases from seven countries (n = 1001). Prevalence was calculated for regions within countries using female population figures from census data. Incidence estimates were calculated for the USA, UK and Switzerland. Regional variation in prevalence and changes in incidence over time were analysed using Poisson regression and linear regression., Results: Prevalence of LAM in the seven countries ranged from 3.4 to 7.8/million women with significant variation, both between countries and between states in the USA. This variation did not relate to the number of pulmonary specialists in the region nor the percentage of population with health insurance, but suggests a large number of patients remain undiagnosed. The incidence of LAM from 2004 to 2008 ranged from 0.23 to 0.31/million women/per year in the USA, UK and Switzerland., Conclusion: Using this method, we have found that the prevalence of LAM is higher than that previously recorded and that many patients with LAM are undiagnosed.

A spiking neural network that learns temporal sequences is described. A sparse code in which individual neurons represent sequences and subsequences enables multiple sequences to be stored without interference. The network is founded on a model of sequence compression in the hippocampus that is robust to variation in sequence element duration and well suited to learn sequences through spike-timing dependent plasticity (STDP). Three additions to the sequence compression model underlie the sparse representation: synapses connecting the neurons of the network that are subject to STDP, a competitive plasticity rule so that neurons specialize to individual sequences, and neural depolarization after spiking so that neurons have a memory. The response to new sequence elements is determined by the neurons that have responded to the previous subsequence, according to the competitively learned synaptic connections. Numerical simulations show that the model can learn sets of intersecting sequences, presented with widely differing frequencies, with elements of varying duration.

A biologically inspired neuronal network that stores and recognizes temporal sequences of symbols is described. Each symbol is represented by excitatory input to distinct groups of neurons (symbol pools). Unambiguous storage of multiple sequences with common subsequences is ensured by partitioning each symbol pool into subpools that respond only when the current symbol has been preceded by a particular sequence of symbols. We describe synaptic structure and neural dynamics that permit the selective activation of subpools by the correct sequence. Symbols may have varying durations of the order of hundreds of milliseconds. Physiologically plausible plasticity mechanisms operate on a time scale of tens of milliseconds; an interaction of the excitatory input with periodic global inhibition bridges this gap so that neural events representing successive symbols occur on this much faster timescale. The network is shown to store multiple overlapping sequences of events. It is robust to variation in symbol duration, it is scalable, and its performance degrades gracefully with perturbation of its parameters.

Optimal nutritional rehabilitation of anorexia nervosa requires more information concerning actual energy and substrate requirements. To this end, indirect calorimetry was performed in female patients (n=34, age 20.9+/-1.2 yr, body mass index [BMI] 15.6+/-0.2 kg/m(2); mean+/-SEM) soon after commencement of refeeding and at the time of discharge from hospital (n=18, BMI 19.0+/-0.3 kg/m(2)). Healthy female controls (n=18, age 24.6+/-1.3 yr, BMI 21.6+/-0.6 kg/m(2)) were also tested. Resting energy expenditure (REE) and respiratory quotient (RQ) were measured in the fasting state, followed by diet-induced thermogenesis (DIT) and RQ over a 4 h period following a 100 g oral glucose load. Compared with post-refeeding patients and controls, pre-refeeding patients had a high basal RQ and a low REE, with a paradoxically higher DIT (13.2+/-0.9% of REE vs. 8.3+/-1.2% and 8.6+/-0.9% in post-refeeding patients and controls, respectively). RQ values in pre-refeeding patients exceeded unity following the glucose load, probably reflecting net lipogenesis, whereas in the post-refeeding patients, post-glucose RQ was similar to that of controls, suggesting premature curtailment of lipogenesis. These data demonstrate energy wasting in emaciated patients with anorexia nervosa. Biological repair processes could account for disproportionate energy loss early in refeeding and there may be some later impediment to full restoration of fat stores.

Starches that are high in amylopectin are digested and absorbed more quickly than starches with a high amylose content and produce larger postprandial glucose and insulin responses. The aim of this study was to test the hypothesis that feeding rats a diet containing quickly digested starch could promote insulin resistance. Sprague-Dawley rats were fed either a high amylopectin or high amylose diet (two 10-g meals per day), and insulin sensitivity was assessed after 9 wk by intravenous glucose tolerance test (IVGTT). In the rats fed the high amylopectin diet, glucose tolerance was significantly lower (P < 0.05) and the insulin response to IVGTT was twice as high as in rats fed the high amylose diet (P < 0.05). A second study using Wistar rats investigated the time course of these changes. Differences in the insulin response to the IVGTT were not evident at 4 wk but began to emerge at 8 wk, and by 12 wk the insulin response was 100% greater in rats fed the high amylopectin diet (P < 0.05) than in those fed the high amylose diet. In addition, basal plasma insulin concentration was higher in rats fed the high amylopectin diet (P < 0.05). There were no differences, however, in glucose tolerance at any time point. The results suggests that quickly digested starch promotes the development of insulin resistance in rats. The relatively slow time course resembles the normal development of insulin resistance in humans.

The effect of immunization route on the kinetics of serum and tear antibody responses to Chlamydia trachomatis was studied in a rat model. Rats received Chlamydia trachomatis serovar C/TW elementary bodies for two immunization cycles by ocular topical (OT) application or subconjunctival (SC) injection and in a second experiment for three immunization cycles by either OT application, gastrointestinal intubation (GI), or intraperitoneal injection (IP). Serum IgG and tear IgA antibodies to whole elementary bodies were measured sequentially following the secondary (2 degrees) and tertiary (3 degrees) immunization cycles. Serum IgG levels were minimal in the OT immunized group following 2 degrees and 3 degrees immunization. Serum IgG levels for the SC, GI, and IP immunized groups rose steadily following 2 degrees immunization reaching maximal levels between day (d)24 and d31. Levels of serum IgG antibodies were highest in the GI group following 3 degrees immunization. Tear IgA antibody responses were greatest in rats immunized by the OT route, the 2 degrees IgA response peaked by d9 and declined by d24. The 3 degrees OT tear IgA response peaked by d13 and was greater than the 2 degrees response. Tear IgA antibody levels in SC and GI immunized rats appeared by d3 following 2 degrees immunization but remained at low levels and were not noted until d20 in the GI group following 3 degrees immunization. Tear IgA antibody responses were not detectable in IP animals following 2 degrees or 3 degrees immunization. This study documents the immunogenicity of Chlamydia trachomatis serovar C/TW in the rat and shows that the OT route is most effective in eliciting IgA antibody responses in tears.

We assayed two classes of immunoregulatory cytokines, colony-stimulating factors (CSF) and interferon (IFN), during and immediately after a primary coccidial infection in chickens. Coccidial infection induces significant alterations in serum colony-stimulating activity (CSA) and these alterations immediately precede the characteristic biphasic leukocytosis. CSA rose sharply during the first 24 h post-inoculation (PI), but returned to control levels by 48 h PI. At this time, we detected an increase in peripheral blood leukocytes which peaked at 96 h PI. A second phase of CSA increase began 96 h PI and peaked at 120-144 h PI which again preceded the second phase of leukocytosis. We also examined the production of IFN during the first 20 days PI. Splenic T cells from Eimeria maxima-infected chickens produced significantly less IFN on day 5 PI compared to T cells from the coccidia-free controls. By days 10 and 15 PI, there was no significant difference in IFN production between the T cells of infected and non-infected chickens. However, by day 20 PI, IFN production by the T cells of the infected birds produced significantly more IFN than the control T cells. The results of our studies indicated the differential production of two different cytokines by chickens during and following a primary coccidial infection. Based on these experiments, CSF may be some of the first cytokines produced during an E. maxima-infection, while IFN may be one of the later cytokines produced.

The authors administered the thyrotropin-releasing hormone (TRH) stimulation test and the dexamethasone suppression test (DST) to 54 patients who met DSM-III criteria for major depressive disorder and to 19 nondepressed patients. A blunted thyrotropin (TSH) response to TRH injection was noted in 18 depressed patients (33%) but in no nondepressed patients. An escape from dexamethasone suppression was noted in 23 depressed patients (43%) but in only 2 nondepressed patients (11%). The combined sensitivity of the DST and the TRH test in identifying major depressive disorder was 67% with 92% specificity. Only 6 depressed patients (11%) had abnormal responses to both the DST and the TRH test, suggesting that the hypothalamic-pituitary-adrenal axis dysregulation and hypothalamic-pituitary-thyroid axis dysregulation are independent phenomena. These findings support the combined use of these neuroendocrine tests in clinical practice.

The dexamethasone suppression test (DST) was administered to 54 primary unipolar depressed patients and 19 non-depressed hospitalized inpatients. Abnormal DST were found in 23 depressed patients (43%) in contrast to 2 (11%) non-depressed patients (P less than 0.05). Within the endogenously depressed group, 69% of patients categorized as familial pure depressive disease (FPDD) in contrast to 13% of depressive spectrum disease (DSD) patients had abnormal DST results (P less than 0.02). The DSD group had significantly fewer abnormal DST results than all other subtypes of unipolar depression (P less than 0.05). The distinction revealed between DSD patients and other endogenously depressed patients may be due to biological factors or due to the heterogeneous nature of the DSD subtype group.

The thyrotropin-releasing hormone (TRH) stimulation test was administered to 47 patients meeting DSM-III criteria for major depressive disorder (with melancholia) and to 19 nondepressed patients. The wide variability of pituitary responses to TRH stimulation noted in the depressed patients provides evidence for the dysregulation of compensatory hypothalamic-pituitary-thyroid function in acute depression. Blunted thyroid-stimulating hormone (TSH) responses to TRH injection were found in 16 depressed (34%) and no nondepressed patients (p less than 0.01). Depressed patients who revealed blunted TSH responses also had blunted prolactin responses to TRH relative to other depressed and nondepressed patient groups (p less than 0.01). These patients (with blunted TSH and prolactin responses) may represent a psychobiologically distinct subgroup of endogenously depressed patients. Augmented (high normal) TSH responses to TRH stimulation were found in eight depressed patients (all women), in contrast to no nondepressed patients. These patients may have a subtle thyroidal dysfunction affecting the underlying endogenous depressive diathesis.

Several studies have suggested that a special relationship exists between premenstrual and major affective disorders. The present report describes the incidence of reported premenstrual symptoms in women with and without prospectively confirmed premenstrual syndrome, women with bipolar or seasonal affective disorder, and controls. The inability of reported symptoms to differentiate women with and without confirmed premenstrual syndrome, as well as the reduced prevalence of reported premenstrual changes in our affective populations relative to previous reports, is discussed.

The thyrotropin releasing hormone (TRH) stimulation test was administered to 54 primary unipolar endogenously depressed and 19 non-depressed hospitalized inpatients. Blunted TSH responses to TRH infusion (delta max TSH less than 7 microunits/ml) were revealed in 18 depressed and no non-depressed patients (P less than 0.01). Augmented TSH responses (delta max TSH greater than 23 microunits/ml) were noted in 8 depressed and no non-depressed patients (P = n.s.). The TRH stimulation test did not distinguish between subtypes of unipolar depression using the familial subtyping criteria of Winokur. These findings are discussed in light of previously reported dexamethasone suppression test subtype distinctions.

This study describes a method for investigating clinical correlates of biological subtypes of depression, using cognitive functioning as the principal behavioral variable. Dexamethasone Suppression Test (DST) escapers were compared to DST suppressors and healthy controls on a battery of learning and memory procedures designed to investigate cognitive functioning in detail. DST suppressors, but not escapers, were cognitively impaired on our tasks. The performance of controls and DST escapers was related to depth of semantic processing, whereas performance of DST suppressors varied inversely with degree of felt hopelessness. Examination of cognitive functioning in future studies may provide useful insights into the clinical significance of biological markers of depression.