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Chronic wasting disease (CWD) is a relentless epidemic disorder caused by infectious prions that threatens the survival of cervid populations and raises increasing public health concerns in North America. In Europe, CWD was detected for the first time in wild Norwegian reindeer (Rangifer tarandus) and moose (Alces alces) in 2016. In this study, we aimed at comparing the strain properties of CWD prions derived from different cervid species in Norway and North America. Using a classical strain typing approach involving transmission and adaptation to bank voles (Myodes glareolus), we found that prions causing CWD in Norway induced incubation times, neuropathology, regional deposition of misfolded prion protein aggregates in the brain, and size of their protease-resistant core, different from those that characterize North American CWD. These findings show that CWD prion strains affecting Norwegian cervids are distinct from those found in North America, implying that the highly contagious North American CWD prions are not the proximate cause of the newly discovered Norwegian CWD cases. In addition, Norwegian CWD isolates showed an unexpected strain variability, with reindeer and moose being caused by different CWD strains. Our findings shed light on the origin of emergent European CWD, have significant implications for understanding the nature and the ecology of CWD in Europe, and highlight the need to assess the zoonotic potential of the new CWD strains detected in Europe.

The aim of this work was to investigate the effects of the currents flowing through surge arresters on the internal insulating textolite structure. The samples were removed from high-voltage arresters that were taken out of service due to malfunction or failure. Discharge (short-circuit) currents of diverse intensities and durations caused degradation effects of varying degrees of advancement in the material of the tested elements. The samples were examined using microscopic methods. The use of the microanalysis technique EDS (energy-dispersive X-ray spectroscopy) made it possible to register changes in the elemental composition of the surface layer of the textolite materials, along with the intensification of the degradation effects. It was found that the high discharge current flows were subject to melting, charring and even burning of the organic adhesive. These effects caused serious changes in the content of elements in the top layer of the textolite and were the cause of a reduction in the service life, durability and reliability of the surge arresters. It was shown that the textolite materials had insufficient resistance to the effects of the emergency operation of the arresters after moisture ingress, which was a consequence of unsealing of the housing. A solution to this problem proposed by the authors could be the use of silicone elastomer as a covering of the textolite internal structure of surge arresters.

Although the fiction of Hong Kong writers Hon Lai-chu and Dorothy Tse Hiu-hung are frequently described as “surreal,” does this term have critical purchase beyond its misleading vernacular use for anything that appears bizarre and fantastical? In Hon’s Empty Faces and Tse’s Owlish, Surrealism proves to be deeply relevant to both writers. Surrealist visuality prioritizes the novels’ literariness and resists reading Hong Kong literature as political allegory. The precarious human face in Hon and the uncanny doll figure in Tse re-enact surreal experiences of disquietude and liminality. While neither novel embraces explicit political stances, both disrupt established lines of thinking and are profoundly relevant to Hong Kong and global issues including neo-liberalism, security, and surveillance. These novels signal the emergence of the Hong Kong neo-Surreal, which highlights imaginaries of risk and affirms Hong Kong literature as world literature .

Abstract Trypanosomiasis is a protozoan infection affecting both human and animals in almost all parts of the world. It can affect a very large range of domestic and wild hosts including camelids, equines, cattle, buffaloes, sheep, goats, pigs, dogs and other carnivores, deer, gazelles and elephants. This review paper was designed to address the effect of this economically important disease in countries on the Red Sea, especially in Egypt, Sudan, Somalia, and Saudi Arabia during the period 2010 to 2020. The prevalence of trypanosomiasis is different between these countries due to different types of diagnostic methods (Giemsa-stained blood smears, Hematocrit centrifugation, Serological test, and molecular analysis PCR) used and differential distribution of vector (Tse tse) flies. In current review, retrospective studies of published literature on distribution and prevalence of Trypanosoma evansi infection in the Red Sea Countries was conducted [Google Scholar and PubMed were used to retrieve the published literature from 2000-2020. A total of 77 published articles met the eligibility criteria and were reviewed. A total of 16 reports have been reported on the prevalence and distribution of Trypnosoma evansi infection in the Red Sea Countries have been from 2010-2020]. According to the published literature, we can say that trypanosomiasis in camels are more prevalent in Sudan than in other countries, followed by 17% and 51.78% in both clinical and non-clinical cases. Hence, the reliable diagnostic tests should be used for rapid treatment or control of the disease as if not treated appropriately in early-stage, can lead to death of the camels. Resumo A tripanossomíase é uma infecção por protozoário que afeta humanos e animais em quase todas as partes do mundo. Pode afetar grande variedade de hospedeiros domésticos e selvagens, incluindo camelídeos, equinos, gado, búfalos, ovelhas, cabras, porcos, cães e outros carnívoros, veados, gazelas e elefantes. Este artigo de revisão foi elaborado para abordar o efeito dessa doença economicamente importante em países do mar Vermelho, especialmente Egito, Sudão, Somália e Arábia Saudita, durante o período de 2010 a 2020. A prevalência de tripanossomíase é diferente entre esses países devido a tipos distintos de métodos diagnósticos (esfregaços de sangue corados com Giemsa, centrifugação de hematócrito, teste sorológico e PCR de análise molecular) usados e distribuição diferencial de moscas vetoras (tsé-tsé). Na revisão atual, foram realizados estudos retrospectivos da literatura publicada sobre distribuição e prevalência da infecção por Trypanosoma evansi nos países do mar Vermelho [Google Scholar e PubMed foram usados para recuperar a literatura publicada de 2000 a 2020. Um total de 77 artigos publicados preencheu os critérios de elegibilidade e foi revisado. E há também 16 relatos sobre a prevalência e distribuição da infecção por Trypnosoma evansi nos países do mar Vermelho, de 2010 a 2020]. De acordo com a literatura publicada, podemos afirmar que a tripanossomíase em camelos é mais prevalente no Sudão do que em outros países, seguida por 17% e 51,78% em casos clínicos e não clínicos. Assim, os testes diagnósticos confiáveis devem ser utilizados para o tratamento rápido ou controle da doença, pois, se eles não forem tratados de forma adequada na fase inicial, isso pode levar à morte dos camelos.

Increasingly, evidence argues that many neurodegenerative diseases, including progressive supranuclear palsy (PSP), are caused by prions, which are alternatively folded proteins undergoing selfpropagation. In earlier studies, PSP prions were detected by infecting human embryonic kidney (HEK) cells expressing a tau fragment [TauRD(LM)] fused to yellow fluorescent protein (YFP). Here, we report on an improved bioassay using selective precipitation of tau prions from human PSP brain homogenates before infection of the HEK cells. Tau prions were measured by counting the number of cells with TauRD(LM)–YFP aggregates using confocal fluorescence microscopy. In parallel studies, we fused α-synuclein to YFP to bioassay α-synuclein prions in the brains of patients who died of multiple system atrophy (MSA). Previously, MSA prion detection required ∼120 d for transmission into transgenic mice, whereas our cultured cell assay needed only 4 d. Variation in MSA prion levels in four different brain regions from three patients provided evidence for three different MSA prion strains. Attempts to demonstrate α-synuclein prions in brain homogenates from Parkinson’s disease patients were unsuccessful, identifying an important biological difference between the two synucleinopathies. Partial purification of tau and α-synuclein prions facilitated measuring the levels of these protein pathogens in human brains. Our studies should facilitate investigations of the pathogenesis of both tau and α-synuclein prion disorders as well as help decipher the basic biology of those prions that attack the CNS.

Deep learning technologies and applications demonstrate one of the most important upcoming developments in radiology. The impact and influence of these technologies on image acquisition and reporting might change daily clinical practice. The aim of this review was to present current deep learning technologies, with a focus on magnetic resonance image reconstruction. The first part of this manuscript concentrates on the basic technical principles that are necessary for deep learning image reconstruction. The second part highlights the translation of these techniques into clinical practice. The third part outlines the different aspects of image reconstruction techniques, and presents a review of the current literature regarding image reconstruction and image post-processing in MRI. The promising results of the most recent studies indicate that deep learning will be a major player in radiology in the upcoming years. Apart from decision and diagnosis support, the major advantages of deep learning magnetic resonance imaging reconstruction techniques are related to acquisition time reduction and the improvement of image quality. The implementation of these techniques may be the solution for the alleviation of limited scanner availability via workflow acceleration. It can be assumed that this disruptive technology will change daily routines and workflows permanently.

To address the discrepancy between the steam parameters extracted by pure condensing units/combined heat and power units and those required by users, this paper introduces the design of a steam screw pressure matcher(SSPM) and determines its optimal steam supply scheme. The SSPM primarily comprises a twin‐screw expander (TSE), twin‐screw compressor(TSC), electric motor, and generator. Initially, models were developed for a 300‐MW subcritical intermediate reheat condensing steam turbine unit, an SSPM, and a desuperheater and pressure reducer(DPR). Subsequently, these models are incorporated into the Ebsilon Professional software to simulate the operational characteristics of the SSPM. The performance parameters of the two options are then compared and analyzed. Simulation results reveal that the operational characteristics of the SSPM closely correlate with the mass flow rate of the TSE. As the TSE mass flow rate varies from 47 to 91 t/h, the efficiency of the TSE declines from 66.3% to 65.3%, while the power performed by the SSPM increases from −2457.978 to 1558.469 kW. Under identical operating conditions, the SSPM scheme exhibits a 6.2%–12.4% improvement in efficiency compared to the DPR scheme. Building upon the aforementioned analysis, the SSPM demonstrates effective cascade utilization of heat steam energy and exhibits favorable regulation characteristics under variable operating conditions. Contrasted with traditional DPR, the SSPM notably mitigates constraints on steam extraction by boilers and enhances the maximum generation efficiency of a single unit. In this study, a steam screw pressure matcher was proposed to solve the problem of mismatched pumping parameters and the user's required steam parameters. The efficiency of this pressure matcher was improved by 6.2%–12.4% compared to a conventional desuperheater.

•Small cerebral vessels segmented from high-resolution 3D black-blood MRI at 3T.•A novel analysis pipeline for vessel density mapping of small cerebral vessels.•Vessel density significantly higher in young subjects compared to aged subjects.•Localized vessel density positively correlated with cognitive scores. Small cerebral blood vessels are largely inaccessible to existing clinical in vivo imaging technologies. This study aims to present a novel analysis pipeline for vessel density mapping of small cerebral blood vessels from high-resolution 3D black-blood MRI at 3T. Twenty-eight subjects (10 under 35 years old, 18 over 60 years old) were imaged with the T1-weighted turbo spin-echo with variable flip angles (T1w TSE-VFA) sequence optimized for black-blood small vessel imaging with iso-0.5 mm spatial resolution (interpolated from 0.51×0.51×0.64 mm3) at 3T. Hessian-based vessel segmentation methods (Jerman, Frangi and Sato filter) were evaluated by vessel landmarks and manual annotation of lenticulostriate arteries (LSAs). Using optimized vessel segmentation, large vessel pruning and non-linear registration, a semiautomatic pipeline was proposed for quantification of small vessel density across brain regions and further for localized detection of small vessel changes across populations. Voxel-level statistics was performed to compare vessel density between two age groups. Additionally, local vessel density of aged subjects was correlated with their corresponding gross cognitive and executive function (EF) scores using Montreal Cognitive Assessment (MoCA) and EF composite scores compiled with Item Response Theory (IRT). Jerman filter showed better performance for vessel segmentation than Frangi and Sato filter which was employed in our pipeline. Small cerebral blood vessels including small artery, arterioles, small veins, and venules on the order of a few hundred microns can be delineated using the proposed analysis pipeline on 3D black-blood MRI at 3T. The mean vessel density across brain regions was significantly higher in young subjects compared to aged subjects. In the aged subjects, localized vessel density was positively correlated with MoCA and IRT EF scores. The proposed pipeline is able to segment, quantify, and detect localized differences in vessel density of small cerebral blood vessels based on 3D high-resolution black-blood MRI. This framework may serve as a tool for localized detection of small vessel density changes in normal aging and cerebral small vessel disease.

The lenticulostriate arteries (LSAs) with small diameters of a few hundred microns take origin directly from the high flow middle cerebral artery (MCA), making them especially susceptible to damage (e.g. by hypertension). This study aims to present high resolution (isotropic ∼0.5 mm), black blood MRI for the visualization and characterization of LSAs at both 3 T and 7 T. T1-weighted 3D turbo spin-echo with variable flip angles (T1w TSE-VFA) sequences were optimized for the visualization of LSAs by performing extended phase graph (EPG) simulations. Twenty healthy volunteers (15 under 35 years old, 5 over 60 years old) were imaged with the T1w TSE-VFA sequences at both 3 T and 7 T. Contrast-to-noise ratio (CNR) was quantified, and LSAs were manually segmented using ITK-SNAP. Automated Reeb graph shape analysis was performed to extract features including vessel length and tortuosity. All quantitative metrics were compared between the two field strengths and two age groups using ANOVA. LSAs can be clearly delineated using optimized 3D T1w TSE-VFA at 3 T and 7 T, and a greater number of LSA branches can be detected compared to those by time-of-flight MR angiography (TOF MRA) at 7 T. The CNR of LSAs was comparable between 7 T and 3 T. T1w TSE-VFA showed significantly higher CNR than TOF MRA at the stem portion of the LSAs branching off the medial middle cerebral artery. The mean vessel length and tortuosity were greater on TOF MRA compared to TSE-VFA. The number of detected LSAs by both TSE-VFA and TOF MRA was significantly reduced in aged subjects, while the mean vessel length measured on 7 T TSE-VFA showed significant difference between the two age groups. The high-resolution black-blood 3D T1w TSE-VFA sequence offers a new method for the visualization and quantification of LSAs at both 3 T and 7 T, which may be applied for a number of pathological conditions related to the damage of LSAs. •High resolution black blood MRI for the visualization of lenticulostriate arteries at 3 and 7 T•More lenticulostriate arteries delineated compared to time-of-flight MRA at 7 T•Vessel morphology quantified with automated Reeb graph shape analysis.•Number and mean vessel length significantly reduced in aged subjects.

This paper presents a novel rigid-body navigation and control architecture within the framework of special Euclidean group SE ( 3 ) and its tangent bundle TSE ( 3 ) while considering stochastic processes in the system. The proposed framework combines the orbit-attitude motions of the rigid body into a single, compact set. The stochastic state filter is designed based on the unscented Kalman filter (UKF) which uses a special retraction function to encode the sigma points onto the manifold. The navigation system is then integrated and evaluated with two different control techniques on TSE ( 3 ) : An almost globally asymptotically stabilizing Morse–Lyapunov-based control system with backstepping and a robust sliding mode-based control system. Also, the performance of the UKF in TSE ( 3 ) proposed here is compared with similar filters in the literature to demonstrate the robustness and accuracy of the proposed filter in a realistic setting. Numerical simulations are conducted to demonstrate the effectiveness of the proposed navigation filter for the full state estimation. In addition, the navigation and control systems are tested in the nonlinear gravity field of a small celestial body with an irregular shape. In particular, the performance of the closed-loop systems is studied in a tracking problem of spacecraft motion near the asteroid Bennu based on OSIRIS-REx mission data.