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An internship programme is a great way to connect what is learnt in class with actual work experience. Existing research has underscored the positive contribution of internship to the educational process and career outcomes among students. The internship programme for students of Faculty of Art, KNUST is a requirement or considered as a compulsory 15 credit hour course for the award of undergraduate degree. As such it is a vital component of the curriculum. Nonetheless, empirical literature on the dynamics of the internship programme at the university is sparse. Without insight into these dynamics however, there will be lack of information that could inform policy and continuous improvement of the programme. To bridge this gap, this paper seeks to analyze the internship experiences of students to determine what factors seem to create the greatest perceived value. The study employed the descriptive exploratory study design approach. Data was obtained from a total of 376 students of the Faculty of Art through the use of questionnaire designed in open and close ended patterns and focus discussions. The statistical package for the social sciences (SPSS) computer package was used for data analysis, while descriptive statistical tools such as frequency and percentage were used to analyze the facts sought from the questionnaire. The students described a variety of skills learned during the internship including mastering the use of some equipment, software, and report writing. About 80% of the participants indicated that the internship programme was important and linked the classroom work to real work environment. All the students regardless of their experiences indicated they had value for the internship which they believe will play a role in their future career objectives. On the other hand, some of the students had some unfavourable experiences including inadequate work space, provision of inadequate PPEs, boring and difficult tasks. Others were engaged in other duties that were not related to their field of studies, all of which could potentially influence the perception of students.

Leptospirosis, one of the most common zoonoses worldwide, (1,2) is caused by Leptospira spp. In humans, its most severe, multiorgan, potentially fatal form is known as Weil's disease (3). Leptospira [...]

Leptospirosis is a common but underdiagnosed zoonosis. We conducted a 1-year prospective study in La Guaira State, Venezuela, analyzing 71 hospitalized patients who had possible leptospirosis and sampling local rodents and dairy cows. Leptospira rrs gene PCR test results were positive in blood or urine samples from 37/71 patients. Leptospira spp. were isolated from cultured blood or urine samples of 36/71 patients; 29 had L. interrogans, 3 L. noguchii, and 4 L. venezuelensis. Conjunctival suffusion was the most distinguishing clinical sign, many patients had liver involvement, and 8/30 patients with L. interrogans infections died. The Leptospira spp. found in humans were also isolated from local rodents; L. interrogans and L. venezuelensis were isolated from cows on a nearby, rodent-infested farm. Phylogenetic clustering of L. venezuelensis isolates suggested a recently expanded outbreak strain spread by rodents. Increased awareness of leptospirosis prevalence and rapid diagnostic tests are needed to improve patient outcomes.

Abstract An extended action fostemsavir (FTR) lipid nanoparticle (LNP) formulation prevents human immunodeficiency virus type one (HIV-1) infection. This FTR formulation establishes a drug depot in monocyte-derived macrophages that extend the drug’s plasma residence time. The LNP’s physicochemical properties improve FTR’s antiretroviral activities, which are linked to the drug’s ability to withstand fluid flow forces and levels of drug cellular internalization. Each is, in measure, dependent on PEGylated lipid composition and flow rate ratios affecting the size, polydispersity, shape, zeta potential, stability, biodistribution, and antiretroviral efficacy. The FTR LNP physicochemical properties enable the drug-particle’s extended actions.

Abstract Background Regulatory T cells (Tregs) maintain immune tolerance. While Treg-mediated neuroprotective activities are now well-accepted, the lack of defined antigen specificity limits their therapeutic potential. This is notable for neurodegenerative diseases where cell access to injured brain regions is required for disease-specific therapeutic targeting and improved outcomes. To address this need, amyloid-beta (Aβ) antigen specificity was conferred to Treg responses by engineering the T cell receptor (TCR) specific for Aβ (TCRA β). The TCRAb were developed from disease-specific T cell effector (Teff) clones. The ability of Tregs expressing a transgenic TCRAβ (TCRAβ -Tregs) to reduce Aβ burden, transform effector to regulatory cells, and reverse disease-associated neurotoxicity proved beneficial in an animal model of Alzheimer’s disease. Methods TCRA β -Tregs were generated by CRISPR-Cas9 knockout of endogenous TCR and consequent incorporation of the transgenic TCRAb identified from Aβ reactive Teff monoclones. Antigen specificity was confirmed by MHC-Aβ-tetramer staining. Adoptive transfer of TCRAβ-Tregs to mice expressing a chimeric mouse-human amyloid precursor protein and a mutant human presenilin-1 followed measured behavior, immune, and immunohistochemical outcomes. Results TCRAβ-Tregs expressed an Aβ-specific TCR. Adoptive transfer of TCRAβ-Tregs led to sustained immune suppression, reduced microglial reaction, and amyloid loads. 18F-fluorodeoxyglucose radiolabeled TCRAβ-Treg homed to the brain facilitating antigen specificity. Reduction in amyloid load was associated with improved cognitive functions. Conclusions TCRAβ-Tregs reduced amyloid burden, restored brain homeostasis, and improved learning and memory, supporting the increased therapeutic benefit of antigen specific Treg immunotherapy for AD. Graphical Abstract

Explicit formulae for the 4×4 Lorentz transformation matrices corresponding to a pure boost and a pure three-dimensional rotation are very well known. Significantly less well known is the explicit formula for a general Lorentz transformation with arbitrary non-zero boost and rotation parameters. We revisit this more general formula by presenting two different derivations. The first derivation (which is somewhat simpler than previous ones appearing in the literature) evaluates the exponential of a 4×4 real matrix A, where A is a product of the diagonal matrix diag(+1,−1,−1,−1) and an arbitrary 4×4 real antisymmetric matrix. The formula for expA depends only on the eigenvalues of A and makes use of the Lagrange interpolating polynomial. The second derivation exploits the observation that the spinor product η†σ¯μχ transforms as a Lorentz four-vector, where χ and η are two-component spinors. The advantage of the latter derivation is that the corresponding formula for a general Lorentz transformation Λ reduces to the computation of the trace of a product of 2×2 matrices. Both computations are shown to yield equivalent expressions for Λ.

It is generally accepted that radiolysis of water on the surface of PuO2 by alpha particles is the source of H2 which can cause pressurisation in sealed storage containers if the material is not adequately conditioned before packing. The mechanisms for this have not been discussed in detail previously. Radiolysis mechanisms of bulk water are summarised and then applied to water at the surface of PuO2. It is shown that the radiolysis processes occurring on timescales of less than 1 ps after energy deposition could have an impact on the storage behaviour of the PuO2 and the potential gas volume generated. Some of the radiolysis products are highly reactive and would be expected to react with plutonium at the surface, affecting the usual water radiolysis processes. A corollary of this observation is that the surface should not be considered a completely crystalline PuO2 solid. It is also highlighted that whilst there are significant uncertainties in the radiolysis process at the PuO2 surface there are also significant uncertainties in H2 formation mechanisms in bulk water. Finally, methods to model the radiolysis process at the surface and the prospects for predictive models are briefly discussed with suggestions for future areas of development.

Dark Matter models that employ a vector portal to a dark sector are usually treated as an effective theory that incorporates kinetic mixing of the photon with a new U(1) gauge boson, with the Z boson integrated out. However, a more complete theory must employ the full SU(2)×L U(1)×Y U(1)Y′ gauge group, in which kinetic mixing of the Z boson with the new U(1) gauge boson is taken into account. The importance of the more complete analysis is demonstrated by an example where the parameter space of the effective theory that yields the observed dark matter relic density is in conflict with a suitably defined electroweak ρ parameter that is deduced from a global fit to Z physics data.

The World Health Organization has recommended dolutegravir (DTG) as a preferred first-line treatment for treatment naive and experienced people living with human immunodeficiency virus type one (PLWHIV). Based on these recommendations 15 million PLWHIV worldwide are expected to be treated with DTG regimens on or before 2025. This includes pregnant women. Current widespread use of DTG is linked to the drug’s high potency, barrier to resistance, and cost-effectiveness. Despite such benefits, potential risks of DTG-linked fetal neurodevelopmental toxicity remain a concern. To this end, novel formulation strategies are urgently needed in order to maximize DTG’s therapeutic potentials while limiting adverse events. In regard to potential maternal fetal toxicities, we hypothesized that injectable long-acting nanoformulated DTG (NDTG) could provide improved safety by reducing drug fetal exposures compared to orally administered native drug. To test this notion, we treated pregnant C3H/HeJ mice with daily oral native DTG at a human equivalent dosage (5 mg/kg; n = 6) or vehicle (control; n = 8). These were compared against pregnant mice injected with intramuscular (IM) NDTG formulations given at 45 (n = 3) or 25 (n = 4) mg/kg at one or two doses, respectively. Treatment began at gestation day (GD) 0.5. Magnetic resonance imaging scanning of live dams at GD 17.5 was performed to obtain T1 maps of the embryo brain to assess T1 relaxation times of drug-induced oxidative stress. Significantly lower T1 values were noted in daily oral native DTG-treated mice, whereas comparative T1 values were noted between control and NDTG-treated mice. This data reflected prevention of DTG-induced oxidative stress when delivered as NDTG. Proteomic profiling of embryo brain tissues harvested at GD 17.5 demonstrated reductions in oxidative stress, mitochondrial impairments, and amelioration of impaired neurogenesis and synaptogenesis in NDTG-treated mice. Pharmacokinetic (PK) tests determined that both daily oral native DTG and parenteral NDTG achieved clinically equivalent therapeutic plasma DTG levels in dams (4,000–6,500 ng/mL). Importantly, NDTG led to five-fold lower DTG concentrations in embryo brain tissues compared to daily oral administration. Altogether, our preliminary work suggests that long-acting drug delivery can limit DTG-linked neurodevelopmental deficits.

In this paper, we study the drift behavior of organic electrochemical transistor (OECT) biosensors in a phosphate-buffered saline (PBS) buffer solution and human serum. Theoretical and experimental methods are illustrated in this paper to understand the origin of the drift phenomenon and the mechanism of ion diffusion in the sensing layer. The drift phenomenon is explained using a first-order kinetic model of ion adsorption into the gate material and shows very good agreement with experimental data on drift in OECTs. We show that the temporal current drift can be largely mitigated using a dual-gate OECT architecture and that dual-gate-based biosensors can increase the accuracy and sensitivity of immuno-biosensors compared to a standard single-gate design. Specific binding can be detected at a relatively low limit of detection, even in human serum.

The 30 yr orbit of the Cepheid Polaris has been followed with observations by the Center for High Angular Resolution Astronomy (CHARA) Array from 2016 through 2021. An additional measurement has been made with speckle interferometry at the Apache Point Observatory. Detection of the companion is complicated by its comparative faintness—an extreme flux ratio. Angular diameter measurements appear to show some variation with pulsation phase. Astrometric positions of the companion were measured with a custom grid-based model-fitting procedure and confirmed with the CANDID software. These positions were combined with the extensive radial velocities (RVs) discussed by Torres to fit an orbit. Because of the imbalance of the sizes of the astrometry and RV data sets, several methods of weighting are discussed. The resulting mass of the Cepheid is 5.13 ± 0.28 M _⊙ . Because of the comparatively large eccentricity of the orbit (0.63), the mass derived is sensitive to the value found for the eccentricity. The mass combined with the distance shows that the Cepheid is more luminous than predicted for this mass from evolutionary tracks. The identification of surface spots is discussed. This would give credence to the identification of a radial velocity variation with a period of approximately 120 days as a rotation period. Polaris has some unusual properties (rapid period change, a phase jump, variable amplitude, and unusual polarization). However, a pulsation scenario involving pulsation mode, orbital periastron passage, and low pulsation amplitude can explain these characteristics within the framework of pulsation seen in Cepheids.

If a planetary nebula (PN) is shown to be a member of a star cluster, we obtain important new constraints on the mass and chemical composition of the PN’s progenitor star, which cannot be determined for PNe in the field. Cluster membership can be tested by requiring the projected separation between the PN and cluster to be within the tidal radius of the cluster, and the objects to have nearly identical radial velocities (RVs) and interstellar extinctions, and nearly identical proper motions (PMs). In an earlier study, we used PMs to confirm that three PNe, which had already passed the other tests, are highly likely to be members of Galactic globular clusters (GCs). For a fourth object, the PN JaFu 1, which lies in the Galactic bulge near the GC Palomar 6 on the sky and has a similar RV, the available PM measurement gave equivocal results. We have now obtained new high-resolution images of the central star of JaFu 1 with the Hubble Space Telescope (HST), which, combined with archival HST frames taken 14 and 16 yr earlier, provide a high-precision PM. Unfortunately, we find that the PM of the central star differs from that of the cluster with high statistical significance. Nevertheless, JaFu 1 is of astrophysical interest because its nucleus appears to be a member of the rare class of “EGB 6-type” central stars, which are associated with compact emission-line knots.

During our spectroscopic survey of central stars of faint planetary nebulae (PNe), we found that the nucleus of Abell 57 exhibits strong nebular emission lines. Using synthetic narrowband images, we show that the emission arises from an unresolved compact emission knot (CEK) coinciding with the hot (90,000 K) central star. Thus Abell 57 belongs to the rare class of “EGB 6-type” PNe, characterized by dense emission cores. Photometric data show that the nucleus exhibits a near-infrared excess, due to a dusty companion body with the luminosity of an M0 dwarf but a temperature of ∼1800 K. Emission-line analysis reveals that the CEK is remarkably dense (electron density ∼ 1.6 × 10 ^7 cm ^−3 ), and has a radius of only ∼4.5 au. The CEK suffers considerably more reddening than the central star, which itself is more reddened than the surrounding PN. These puzzles may suggest an interaction between the knot and central star; however, Hubble Space Telescope imaging of EGB 6 itself shows that its CEK lies more than ∼125 au from the PN nucleus. We discuss a scenario in which a portion of the asymptotic giant branch wind that created the PN was captured into a dust cloud around a distant stellar companion; this cloud has survived to the present epoch, and has an atmosphere photoionized by radiation from the hot central star. However, in this picture EGB 6-type nuclei should be relatively common, yet they are actually extremely rare; thus they may arise from a different transitory phenomenon. We suggest future observations of Abell 57 that may help unravel its mysteries.

We present optical spectroscopy of the 12th-magnitude central star of the planetary nebula (PN) Patchick 27 (Pa 27), obtained during a survey of faint PN nuclei (PNNs) with the Low-Resolution Spectrograph of the Hobby–Eberly Telescope. The optical spectrum of Pa 27 is that of a K0 III red giant with rotationally broadened lines. However, the star is detected in the near-ultraviolet (near-UV) with GALEX, showing that a hot binary component is also present. The spectral-energy distribution from the near-UV to the mid-infrared can be fitted with a combination of the K0 III giant and a hot PNN with an effective temperature of about 50,000 K. Photometric observations of Pa 27, both ground-based and from TESS, show a low-amplitude sinusoidal variation with a period of 7.36 days, probably due to starspots on a rotating and magnetically active cool giant. Pa 27 is a new member of the rare class of “A35-type central stars,” which are binary PNNs consisting of a spotted late-type star and a hot pre–white dwarf. They are likely the result of a situation where an asymptotic-giant-branch (AGB) star ejects its outer layers in a dense wind, part of which is captured by a distant companion, spinning up its rotation by accretion of material and angular momentum. We suggest several useful follow-up observations.

Disordered immunity, aging, human immunodeficiency virus type one (HIV-1) infection, and responses to antiretroviral therapy are linked. However, how each factor is linked with the other(s) remains incompletely understood. It has been reported that accelerated aging, advanced HIV-1 infection, inflammation, and host genetic factors are associated with host cellular, mitochondrial, and metabolic alterations. However, the underlying mechanism remains elusive. With these questions in mind, we used chronically HIV-1-infected CD34-NSG humanized mice (hu-mice) to model older people living with HIV and uncover associations between HIV-1 infection and aging. Adult humanized mice were infected with HIV-1 at the age of 20 weeks and maintained for another 40 weeks before sacrifice. Animal brains were collected and subjected to transcriptomics, qPCR, and immunofluorescence assays to uncover immune disease-based biomarkers. CD4+ T cell decline was associated with viral level and age. Upregulated C1QA, CD163, and CXCL16 and downregulated LMNA and CLU were identified as age-associated genes tied to HIV-1 infection. Ingenuity pathway analysis affirmed links to innate immune activation, pyroptosis signaling, neuroinflammation, mitochondrial dysfunction, cellular senescence, and neuronal dysfunction. In summary, CD34-NSG humanized mice are identified as a valuable model for studying HIV-1-associated aging. Biomarkers of immune senescence and neuronal signaling are both age- and virus-associated. By exploring the underlying biological mechanisms that are linked to these biomarkers, interventions for next generation HIV-1-infected patients can be realized.

The success of long-acting (LA) drug delivery systems (DDSs) is linked to their biocompatible polymers. These are used for extended therapeutic release. For treatment or prevention of human immune deficiency virus type one (HIV-1) infection, LA DDSs hold promise for improved regimen adherence and reduced toxicities. Current examples include Cabenuva, Apretude, and Sunlenca. Each is safe and effective. Alternative promising DDSs include implants, prodrugs, vaginal rings, and microarray patches. Each can further meet patients’ needs. We posit that the physicochemical properties of the formulation chemical design can optimize drug release profiles. We posit that the strategic design of LA DDS polymers will further improve controlled drug release to simplify dosing schedules and improve regimen adherence.

The direction and magnitude of tundra vegetation productivity trends inferred from the normalized difference vegetation index (NDVI) have exhibited spatiotemporal heterogeneity over recent decades. This study examined the spatial and temporal drivers of Moderate Resolution Imaging Spectroradiometer Max NDVI (a proxy for peak growing season aboveground biomass) and time-integrated (TI)-NDVI (a proxy for total growing season productivity) on the Yamal Peninsula, Siberia, Russia between 2001 and 2018. A suite of remotely-sensed environmental drivers and machine learning methods were employed to analyze this region with varying climatological conditions, landscapes, and vegetation communities to provide insight into the heterogeneity observed across the Arctic. Summer warmth index, the timing of snowmelt, and physiognomic vegetation unit best explained the spatial distribution of Max and TI-NDVI on the Yamal Peninsula, with the highest mean Max and TI-NDVI occurring where summer temperatures were higher, snowmelt occurred earlier, and erect shrub and wetland vegetation communities were dominant. Max and TI-NDVI temporal trends were positive across the majority of the Peninsula (57.4% [5.0% significant] and 97.6% [13.9% significant], respectively) between 2001 and 2018. Max and TI-NDVI trends had variable relationships with environmental drivers and were primarily influenced by coastal-inland gradients in summer warmth and soil moisture. Both Max and TI-NDVI were negatively impacted by human modification, highlighting how human disturbances are becoming an increasingly important driver of Arctic vegetation dynamics. These findings provide insight into the potential future of Arctic regions experiencing warming, moisture regime shifts, and human modification, and demonstrate the usefulness of considering multiple NDVI metrics to disentangle the effects of individual drivers across heterogeneous landscapes. Further, the spatial heterogeneity in the direction and magnitude of interannual covariation between Max NDVI, TI-NDVI, and climatic drivers highlights the difficulty in generalizing the effects of individual drivers on Arctic vegetation productivity across large regions.

Satellite-derived Ecosystem Functional Types (EFTs) are increasingly used in ecology and conservation to characterize ecosystem heterogeneity. The diversity of EFTs, also known as Ecosystem Functional Diversity (EFD), has been suggested both as a potential metric of ecosystem-level biodiversity and as a predictor for ecosystem functioning, ecosystem services, and resilience. However, the impact of key methodological choices on patterns of EFTs and EFD have not been formally assessed. Using Costa Rica as a study system, we compared EFTs and EFD, derived from MODIS and Landsat data using different methodological assumptions, at both national and local extents. Our results showed that the regional spatial patterns of EFTs and EFD derived from 250 m MODIS and 30 m Landsat are notably different. The selection of sensors for deriving EFTs and EFD is dependent on the study area, data quality, and the research objective. Given its finer spatial resolution, Landsat has greater capacity to differentiate more EFTs than MODIS, though MODIS could be a better choice in frequently cloudy areas due to its shorter revisiting time. We also found that the selection of spatial extent used to derive EFD is critical, as smaller extents (e.g., at a local rather than a national scale) can show much higher diversity. However, diversity levels derived at smaller extents appear to be nested within the diversity levels derived at larger extents. As EFTs and EFD continue to develop as a tool for ecosystem ecology, we highlight the important methodological choices to ensure that these metrics best fit research objectives.

Here, using animal models, Deodhar et al. single parenteral dose of dolutegravir (DTG) prodrug nanocrystals sustains drug protein-adjusted 90% inhibitory concentration for up to a year, without injection site reactions or systemic toxicities.

Most institutions of higher education presume that the pursuit of truth is central to their missions. However, the status of truth has been seriously challenged in contemporary society--by postmodern critiques, confusion about the goals and methods of scholarly disciplines, and the seductive power of social and other digital media. In this essay, we describe a major empirical study of higher education in the United States. While faculty and senior administrators continue to value scholarship, a majority of students in the United States adopt a transactional approach to their education; and many of them are beleaguered by mental health challenges as well as feelings of alienation. These factors constitute a significant challenge to the laudable goals of the project 'Positive Learning in the Age of Information' (PLATO), which focuses on student learning in higher education. The authors recommend a sharp focus on the scholarly pursuit and elucidation of truth--beginning with admission to college (onboarding), if not before; highlighted and intertwined with all course work; and foregrounded as well in all institutions on campus (library, museums, research laboratories).

The high prevalence of the modern Beijing sublineage of Mycobacterium tuberculosis may be related to increased virulence, although the responsible mechanisms remain poorly understood. We previously described enhanced triacylglycerol accumulation in modern Beijing strains. Here we show that modern Beijing strains grow faster in vitro and trigger a vigorous immune response and pronounced macrophage infiltration. Transcriptomic analysis of bone marrow derived macrophages infected with modern Beijing lineage strains revealed a significant enrichment of infection, cholesterol homeostasis and amino acid metabolic pathways. The upregulation of proinflammatory / bactericidal cytokines was confirmed by RT-PCR analysis, which is also in consistent with the reduced bacterial burden in modern strains infected macrophages. These results suggest that modern Beijing strains elicit a hyperinflammatory response which might indicate a stronger virulence and contribute to their extensive global prevalence.

Do salient distractors have the power to automatically capture attention? This question has led to a heated debate concerning the role of salience in attentional control. A potential resolution, called the signal suppression hypothesis, has proposed that salient items produce a bottom-up signal that vies for attention, but that salient stimuli can be suppressed via top-down control to prevent the capture of attention. This hypothesis, however, has been criticized on the grounds that the distractors used in initial studies of support were weakly salient. It has been difficult to know how seriously to take this low-salience criticism because assertions about high and low salience were made in the absence of a common (or any) measure of salience. The current study used a recently developed psychophysical technique to compare the salience of distractors from two previous studies at the center of this debate. Surprisingly, we found that the original stimuli criticized as having low salience were, if anything, more salient than stimuli from the later studies that purported to increase salience. Follow-up experiments determined exactly why the original stimuli were more salient and tested whether further improving salience could cause attentional capture as predicted by the low-salience account. Ultimately, these findings challenge purely stimulus-driven accounts of attentional control. Public Significance Statement: This study aimed to understand whether highly salient stimuli have the power to automatically attract attention. Using a new method to measure salience, we found evidence that is inconsistent with theoretical accounts claiming that stimuli of sufficient salience cannot be ignored. [ABSTRACT FROM AUTHOR]

Explicit formulae for the 4 × 4 Lorentz transformation matrices corresponding to a pure boost and a pure three-dimensional rotation are very well known. Significantly less well known is the explicit formula for a general Lorentz transformation with arbitrary non-zero boost and rotation parameters. We revisit this more general formula by presenting two different derivations. The first derivation (which is somewhat simpler than previous ones appearing in the literature) evaluates the exponential of a 4 × 4 real matrix A, where A is a product of the diagonal matrix diag (+ 1 , − 1 , − 1 , − 1) and an arbitrary 4 × 4 real antisymmetric matrix. The formula for exp A depends only on the eigenvalues of A and makes use of the Lagrange interpolating polynomial. The second derivation exploits the observation that the spinor product η † σ ¯ μ χ transforms as a Lorentz four-vector, where χ and η are two-component spinors. The advantage of the latter derivation is that the corresponding formula for a general Lorentz transformation Λ reduces to the computation of the trace of a product of 2 × 2 matrices. Both computations are shown to yield equivalent expressions for Λ. [ABSTRACT FROM AUTHOR]