bluuebunny/crossref_metadata_2025 huggingface dataset:
High School Educator Training by Simulation to Address Emotional and Behavioral Concerns in School Settings: A Randomized Study
Authors: Albright Glenn , Fazel Mina , Khalid Nikita , McMillan Jeremiah , Hilty Don , Shockley Kristen , Joshi Shashank
Published: March 2022

The purpose of this study is to examine the impact of an online virtual human role-play simulation in teaching high school educators and staff to identify, talk to, and if necessary, refer students in psychological distress to support services. High school educators (N = 31,144) from 43 US states and 5 American territories completed a baseline survey and then randomly assigned to a wait-list control or treatment group. Participants in the treatment group completed the training simulation which included active learning strategies to teach evidenced-based communication strategies such as motivational interviewing to build skills and shift attitudes. Immediately after the training, treatment group participants completed a post-survey and then a 3-month follow-up survey. Baseline and post-surveys included the validated gatekeeper behavior scale measures which assess attitudinal constructs that predict helping behaviors. Self-reported helping behaviors were collected at baseline from both groups and at the 3-month follow-up for the treatment group. The treatment group participants’ post and follow-up data were compared to the control group’s baseline measures. The treatment group post-training scores were significantly higher (p < .001) than the control group’s baseline scores for all gatekeeper behavior scale attitudinal constructs of preparedness, likelihood, and self-efficacy to engage in helping behaviors. A teacher subsample reported significant increases (p < .001) in the number of students referred to mental health support services when compared to baseline measures of the control group. Role-play simulations hold promise in teaching educators to become the “eyes and ears” of student mental health by empowering them to identify students in psychological distress, engage them in effective conversations about their concerns, and if necessary, make a referral to behavioral health support services. Future studies need to implement measures that document students entering counseling as a result of self-reported referrals and examine the impact of the training on the overall mental health culture within schools. Such studies could lead to simulations being widely adopted to support public health initiatives that address student mental health and wellness.
Longitudinal Vibration Analysis of a Stepped Nonlocal Rod Embedded in Several Elastic Media
Authors: Taima Moustafa S. , El-Sayed Tamer , Farghaly Said H.
Published: March 2022

Purpose

Mechanical properties of 1D nanostructures are of great importance in nanoelectromechanical systems (NEMS) applications. The free vibration analysis is a non-destructive technique for evaluating Young's modulus of nanorods and for detecting defects in nanorods. Therefore, this paper aims to study the longitudinal free vibration of a stepped nanorod embedded in several elastic media.

Methods

The analysis is based on Eringen’s nonlocal theory of elasticity. The governing equation is obtained using Hamilton’s principle and then transformed into the nonlocal analysis. The dynamic stiffness matrix (DSM) method is used to assemble the rod segments equations. The case of a two-segment nanorod embedded in two elastic media is then deeply investigated.

Results

The effect of changing the elastic media stiffness, the segments stiffness ratio, boundary conditions and the nonlocal parameter are examined. The nano-rod spectrum and dispersion relations are also investigated.

Conclusion

The results show that increasing the elastic media stiffness and the segment stiffness ratio increases the natural frequencies. Furthermore, increasing the nonlocal parameter reduces natural frequencies slightly at lower modes and significantly at higher modes.
A comprehensive high-resolution gridded emission inventory of anthropogenic sources of air pollutants in Indian megacity Kolkata
Authors: Mangaraj Poonam , Sahu Saroj Kumar , Beig Gufran , Yadav Ravi
Published: March 2022

In this study, we present a first-ever effort made to develop an ultra-high-resolution gridded emission inventory (i.e. ~ 0.4 km ×  ~ 0.4 km) for the Indian megacity Kolkata. As the rising demand for fossil fuels based energy along with the spread of urban corridors have forced the anthropogenic activities to a mounting level, therefore determining the sources responsible is of paramount importance. This has worsened not only the regional air quality but also has an indirect effect on the global air quality. The spatial and temporal variation of the source requires an accurate estimation of the surface emission which is the most essential parameter to study the air quality, that positively has been fulfilled in this study. The annual emission for 2020 is calculated to be 37.2 Gg/yr of PM2.5, 61.4 Gg/yr of PM10, 222.6 Gg/yr of CO, 131.3 Gg/yr of NOx, 60.3 Gg/yr of SO2, 120.4 Gg/yr of VOC, 9.5 Gg/yr of BC and 16.8 Gg/yr of OC that prevails in the toxic air of megacity Kolkata. The present surface chemistry dataset will be the first line of detailed information regarding emission hotspots in the megacity that could be used as important tool for clean air mitigation strategies, input into the air quality modeling study to tackle environmental issues, and public health.

Article Highlights

Identification of sources of pollutants through spatially resolved high-resolution inventory in megacity Kolkata.

Unlike transport and industrial sector, municipal solid waste burning has emerged as another big source.

Present information is vital for policy making to mitigate air quality issues and modeling studies.
Circular Economy of Water: Definition, Strategies and Challenges
Authors: Morseletto Piero , Mooren Caro Eline , Munaretto Stefania
Published: March 2022

The circular economy has attracted considerable attention also in relation to water, an indispensable element to the sustainment of life and a critical input resource for the world economy. Despite a growing body of research on the circular economy of water (CEW), a consistent terminology and a clear conceptualisation of CEW strategies are lacking. Without such aspects, decision-makers, scientists and professionals may be hindered in developing a shared understanding of problems and solutions and exploiting new opportunities in the domain of the CEW. Furthermore, we argue that water is a unique element in the circular economy because it is a resource, a product and a service with no equivalent in the economic system and should be considered and valued as such in the CEW. Accordingly, we provide the definition of the CEW as an economic framework for reducing, preserving and optimising the use of water through waste avoidance, efficient utilisation and quality retention while ensuring environmental protection and conservation. Building on an analysis of academic literature and cases studies, we outline and illustrate a set of nine CEW strategies, including Rethink, Avoid, Reduce, Replace, Reuse, Recycle, Cascade, Store and Recover. Finally, we identify normative (legislation), governance (roles and responsibilities) and implementation (barriers and opportunities for application) challenges that need to be addressed to facilitate the transition to a comprehensive CEW.
Consciousness and Attention in the Bhagavad Gita
Authors: MAITRA KEYA
Published: March 2022

Consciousness is a central topic in Hindu philosophy. This is because this philosophy understands reality in terms of brahman or atman (typically translated as the self), and consciousness is conceived as the essential marker of self. The prominent Hindu text Bhagavad Gita offers an exception. Self is conceived in the Gita not in terms of its essential identity with pure or transcendental consciousness. But the question remains, does the Gita still offer us a theory of consciousness? The goal of my paper is to show that the Gita can be taken as offering an interesting empirical theory of consciousness. My paper focuses on determining the nature of attention in the Gita's understanding of yoga, and to articulate the role of such attention in the Gita's theory of consciousness. My working conclusion is that what differentiates an ordinary person's consciousness from a yogi's consciousness is the nature of their attention both in terms of its manner and its object. I argue, further, that exploring the Gita's theory of consciousness, especially in conjunction with the nature of attention, is immensely fruitful because it allows us to see the Gita's potential contribution to our contemporary philosophical discussion of consciousness and attention. This is because bringing the Gita into discussion allows us to appreciate a dimension of the metaphysics of attention–namely, the dimension of manner of attending and its cultivation, and the moral and social implications in the proposed redirection of one's attention--not often recognized in the contemporary Western discussion.
Power divider network for dual-fed adaptive antenna
Authors: Fischer Serafin B. , Hesselbarth Jan
Published: March 2022

Exposing the near field of an antenna to varying dielectric environment causes changes of the antenna input impedance and, thus, unwanted feed mismatch. Feeding such an antenna at different points, and selecting an appropriate feed for best match at a given scenario, may solve the problem. For the case of two scenarios of different dielectric environments and an antenna with two feed points, this work presents a passive power divider network, which keeps the antenna matched to the source in either scenario. Specific impedance transformations in the two branches of the divider network realize power transfer in a first scenario from the source to complex feed impedance at the first antenna feed, while in a second scenario, with now different antenna feed impedances, matched power transfer is from the source to the second antenna feed. Analytical formulae are derived for the design of the divider network. An experiment uses an example antenna with two feeds and a microstrip divider network, connected to a common 50 ohm port. Measurements are conducted with the antenna radiating, first, in air and, secondly, into butter. The measurements show antenna match at 1 GHz in either case and agree well with the analytical results.
Bone marrow mesenchymal stem cell-derived exosomal microRNA-381-3p alleviates vascular calcification in chronic kidney disease by targeting NFAT5
Authors: Liu Yingjie , Guo Yan , Bao Shumin , Huang Hongdong , Liu Wenhu , Guo Weikang
Published: March 2022

Vascular calcification (VC) is a significant complication of chronic kidney disease (CKD) and cellular apoptosis is one of the intricate mechanisms of VC. Bone marrow mesenchymal stem cell-derived exosome (BMSC-Exo) alleviates VC, but the mechanism remains unclear. We investigated the mechanism of BMSC-Exo using high phosphate stimulated Human aortic smooth muscle cells (HA-VSMCs) and 5/6 subtotal nephrectomy (SNx) rat models. We demonstrated that the effect of BMSC-Exo on the inhibition of cellular apoptosis and calcification partially depended on exosomal microRNA-381-3p (miR-381-3p) both in vivo and in vitro, and confirmed that miR-381-3p could inhibit Nuclear Factor of Activated T cells 5 (NFAT5) expression by directly binding to its 3′ untranslated region. Additionally, we found that severe calcification of arteries in dialysis patients was associated with decreased miR-381-3p and increased NFAT5 expression levels. Collectively, our findings proved that BMSC-Exo plays anti-calcification and anti-apoptosis roles in CKD by delivering enclosed miR-381-3p, which directly targets NFAT5 mRNA, and leads to a better understanding of the mechanism of CKD-VC.
Video-rate high-precision time-frequency multiplexed 3D coherent ranging
Authors: Qian Ruobing , Zhou Kevin C. , Zhang Jingkai , Viehland Christian , Dhalla Al-Hafeez , Izatt Joseph A.
Published: March 2022

Frequency-modulated continuous wave (FMCW) light detection and ranging (LiDAR) is an emerging 3D ranging technology that offers high sensitivity and ranging precision. Due to the limited bandwidth of digitizers and the speed limitations of beam steering using mechanical scanners, meter-scale FMCW LiDAR systems typically suffer from a low 3D frame rate, which greatly restricts their applications in real-time imaging of dynamic scenes. In this work, we report a high-speed FMCW based 3D imaging system, combining a grating for beam steering with a compressed time-frequency analysis approach for depth retrieval. We thoroughly investigate the localization accuracy and precision of our system both theoretically and experimentally. Finally, we demonstrate 3D imaging results of multiple static and moving objects, including a flexing human hand. The demonstrated technique achieves submillimeter localization accuracy over a tens-of-centimeter imaging range with an overall depth voxel acquisition rate of 7.6 MHz, enabling densely sampled 3D imaging at video rate.
Microbes contribute to setting the ocean carbon flux by altering the fate of sinking particulates
Authors: Nguyen Trang T. H. , Zakem Emily J. , Ebrahimi Ali , Schwartzman Julia , Caglar Tolga , Amarnath Kapil , Alcolombri Uria , Peaudecerf François J. , Hwa Terence , Stocker Roman , Cordero Otto X. , Levine Naomi M.
Published: March 2022

Sinking particulate organic carbon out of the surface ocean sequesters carbon on decadal to millennial timescales. Predicting the particulate carbon flux is therefore critical for understanding both global carbon cycling and the future climate. Microbes play a crucial role in particulate organic carbon degradation, but the impact of depth-dependent microbial dynamics on ocean-scale particulate carbon fluxes is poorly understood. Here we scale-up essential features of particle-associated microbial dynamics to understand the large-scale vertical carbon flux in the ocean. Our model provides mechanistic insight into the microbial contribution to the particulate organic carbon flux profile. We show that the enhanced transfer of carbon to depth can result from populations struggling to establish colonies on sinking particles due to diffusive nutrient loss, cell detachment, and mortality. These dynamics are controlled by the interaction between multiple biotic and abiotic factors. Accurately capturing particle-microbe interactions is essential for predicting variability in large-scale carbon cycling.
BAF complex-mediated chromatin relaxation is required for establishment of X chromosome inactivation
Authors: Keniry Andrew , Jansz Natasha , Gearing Linden J. , Wanigasuriya Iromi , Chen Joseph , Nefzger Christian M. , Hickey Peter F. , Gouil Quentin , Liu Joy , Breslin Kelsey A. , Iminitoff Megan , Beck Tamara , Tapia del Fierro Andres , Whitehead Lachlan , Jarratt Andrew , Kinkel Sarah A. , Taberlay Phillippa C. , Willson Tracy , Pakusch Miha , Ritchie Matthew E. , Hilton Douglas J. , Polo Jose M. , Blewitt Marnie E.
Published: March 2022

The process of epigenetic silencing, while fundamentally important, is not yet completely understood. Here we report a replenishable female mouse embryonic stem cell (mESC) system, Xmas, that allows rapid assessment of X chromosome inactivation (XCI), the epigenetic silencing mechanism of one of the two X chromosomes that enables dosage compensation in female mammals. Through a targeted genetic screen in differentiating Xmas mESCs, we reveal that the BAF complex is required to create nucleosome-depleted regions at promoters on the inactive X chromosome during the earliest stages of establishment of XCI. Without this action gene silencing fails. Xmas mESCs provide a tractable model for screen-based approaches that enable the discovery of unknown facets of the female-specific process of XCI and epigenetic silencing more broadly.
Phage peptides mediate precision base editing with focused targeting window
Authors: Jia Kun , Cui Yan-ru , Huang Shisheng , Yu Peihong , Lian Zhengxing , Ma Peixiang , Liu Jia
Published: March 2022

Base editors (BEs) are genome engineering tools that can generate nucleotide substitutions without introducing double-stranded breaks (DSBs). A variety of strategies have been developed to improve the targeting scope and window of BEs. In a previous study, we found that a bacteriophage-derived peptide, referred to as G8PPD, could improve the specificity of Cas9 nuclease. Herein, we investigate the applicability of G8PPD as molecular modulators of BEs. We show that G8PPD can improve cytidine base editor (CBEs) and adenine base editor (ABE) to more focused targeting windows. Notably, in a cell-based disease model, G8PPD increases the percentage of perfectly edited gene alleles by BEs from less than 4% to more than 38% of the whole population. In addition, G8PPD can improve the targeting scope of BE in mouse embryos. In summary, our study presents the peptidyl modulators that can improve BEs for precision base editing.
DNA methylation maintenance at the p53 locus initiates biliary-mediated liver regeneration
Authors: He Jianbo , Zhou Yang , Qian Chuanfang , Wang Danyang , Yang Zhuolin , Huang Zhuofu , Sun Junhui , Ni Rui , Yang Qifen , Chen Jingying , Luo Lingfei
Published: March 2022

In cases of extensive liver injury, biliary epithelial cells (BECs) dedifferentiate into bipotential progenitor cells (BPPCs), then redifferentiate into hepatocytes and BECs to accomplish liver regeneration. Whether epigenetic regulations, particularly DNA methylation maintenance enzymes, play a role in this biliary-mediated liver regeneration remains unknown. Here we show that in response to extensive hepatocyte damages, expression of dnmt1 is upregulated in BECs to methylate DNA at the p53 locus, which represses p53 transcription, and in turn, derepresses mTORC1 signaling to activate BEC dedifferentiation. After BEC dedifferentiation and BPPC formation, DNA methylation at the p53 locus maintains in BPPCs to continue blocking p53 transcription, which derepresses Bmp signaling to induce BPPC redifferentiation. Thus, this study reveals promotive roles and mechanisms of DNA methylation at the p53 locus in both dedifferentiation and redifferentiation stages of biliary-mediated liver regeneration, implicating DNA methylation and p53 as potential targets to stimulate regeneration after extensive liver injury.
Virucidal efficacy of laundry sanitizers against SARS-CoV-2 and other coronaviruses and influenza viruses
Authors: Khalid Ijaz M. , Nims Raymond W. , McKinney Julie , Gerba Charles P.
Published: March 2022

The clothes laundering process affords numerous opportunities for dissemination of infectious virus from contaminated clothing to appliance surfaces and other household surfaces and eventually to launderer’s hands. We have explored the efficacy of laundry sanitizers for inactivating coronaviruses and influenza viruses. Virucidal efficacy was tested using standardized suspension inactivation methods (EN 14476) or hard-surface inactivation methods (ASTM E1053-20) against SARS-CoV-2, human coronavirus 229E (HCoV 229E), influenza A virus (2009-H1N1 A/Mexico), or influenza B virus (B/Hong Kong). Efficacy was measured in terms of log10 reduction in infectious virus titer, after 15 min contact time (suspension studies) or 5 min contact time (hard surface studies) at 20 ± 1 °C. In liquid suspension studies, laundry sanitizers containing p-chloro-m-xylenol (PCMX) or quaternary ammonium compounds (QAC) caused complete inactivation (≥ 4 log10) of HCoV 229E and SARS-CoV-2 within 15 min contact time at 20 ± 1 °C. In hard surface studies, complete inactivation (≥ 4 log10) of each coronavirus or influenza virus, including SARS-CoV-2, was observed following a 5-min contact time at 20 ± 1 °C. Respiratory viruses may remain infectious on clothing/fabrics and environmental surfaces for hours to days. The use of a laundry sanitizer containing microbicidal actives may afford mitigation of the risk of contamination of surfaces during handling of the laundry and washing appliances (i.e., washer/dryer or basin), adjacent surfaces, the waste water stream, and the hands of individuals handling clothes contaminated with SARS-CoV-2, influenza viruses, or other emerging enveloped viruses.
Recognizing megatsunamis in Mediterranean deep sea sediments based on the massive deposits of the 365 CE Crete event
Authors: Polonia A. , Nelson C. H. , Vaiani S. C. , Colizza E. , Gasparotto G. , Giorgetti G. , Bonetti C. , Gasperini L.
Published: March 2022

The Mediterranean Sea hosts two subduction systems along the convergent Africa-Eurasia plate boundary that have produced strong ground shaking and generated tsunamis. Based on historical descriptions and sedimentary records, one of these events, in 365 CE, impacted a broad geographical area, including tsunami evidence for distances of 700–800 km from the source event, qualifying it as a ‘megatsunami’. Understanding how megatsunamis are produced, and where they are more likely, requires a better understanding of the different secondary processes linked to these events such as massive slope failures, multiple turbidity current generation, and basin seiching. Our sedimentary records from an extensive collection of cores located in distal and disconnected basins, identify turbidites which are analyzed using granulometry, elemental (XRF), micropaleontological, and geochemical data in order to reconstruct their coastal or marine source. The results show that the 365 CE basin floor sediments are a mixture of inner shelf and slope materials. The tsunami wave produced multiple far-field slope failures that resulted in stacked basal turbidites. It also caused transport of continent-derived organic carbon and deposition over basal turbidites and into isolated basins of the deep ocean. The composition of sediment in isolated basins suggests their deposition by large-scale sheet like flows similar to what has been caused by the Tohoku earthquake associated tsunamis. This is significant for rectifying and resolving where risk is greatest and how cross-basin tsunamis are generated. Based on these results, estimates of the underlying deposits from the same locations were interpreted as possible older megatsunamis.
Predictors of permanent pacemaker implantation after sinus conversion of cavotricuspid isthmus-dependent atrial flutter
Authors: Kim Juwon , Lee Sung Ho , Kim Hye Ree , Chung Tae-Wan , Choi Ji-Hoon , Kim Ju Youn , Park Seung-Jung , On Young Keun , Kim June Soo , Park Kyoung-Min
Published: March 2022

It is unclear which factors are associated with progressive sinus node dysfunction after cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL) ablation. We sought to evaluate the incidence and predictors for permanent pacemaker (PPM) implantation after CTI-dependent AFL ablation. Between January 2011 and June 2021, 353 patients underwent CTI-dependent AFL ablation were studied. During a median follow-up of 31.6 months, 30 patients (8.5%) received PPM implantation, 24 for sick sinus syndrome and 6 for atrioventricular block. In multivariable model, prior atrial fibrillation (AF) (HR 3.570; 95% CI 1.034–12.325; P = 0.044), lowest previous sinus heart rate (HR 0.942; 95% CI 0.898–0.988; P = 0.015), and left atrial volume index (LAVI) (HR 1.067; 95% CI 1.024–1.112; P = 0.002) were independently associated with PPM implantation after CTI-dependent AFL ablation. The best cut-off points for predicting PPM implantation were 60.1 ml/m2 for LAVI and 46 beats per minute for lowest previous sinus heart rate. Among the patients discharged without PPM implantation after ablation, sinus pause over three seconds at AFL termination during ablation was an independent predictor of PPM implantation (HR 17.841; 95% CI 4.626–68.807; P < 0.001). Physicians should be aware of the possibility of PPM implantation during follow-up after AFL ablation, especially in patients with the relevant risk factors.
Activated endothelial cells induce a distinct type of astrocytic reactivity
Authors: Taylor Xavier , Cisternas Pablo , Jury Nur , Martinez Pablo , Huang Xiaoqing , You Yanwen , Redding-Ochoa Javier , Vidal Ruben , Zhang Jie , Troncoso Juan , Lasagna-Reeves Cristian A.
Published: March 2022

Reactive astrogliosis is a universal response of astrocytes to abnormal events and injuries. Studies have shown that proinflammatory microglia can polarize astrocytes (designated A1 astrocytes) toward a neurotoxic phenotype characterized by increased Complement Component 3 (C3) expression. It is still unclear if inflammatory stimuli from other cell types may also be capable of inducing a subset of C3+neurotoxic astrocytes. Here, we show that a subtype of C3+neurotoxic astrocytes is induced by activated endothelial cells that is distinct from astrocytes activated by microglia. Furthermore, we show that endothelial-induced astrocytes have upregulated expression of A1 astrocytic genes and exhibit a distinctive extracellular matrix remodeling profile. Finally, we demonstrate that endothelial-induced astrocytes are Decorin-positive and are associated with vascular amyloid deposits but not parenchymal amyloid plaques in mouse models and AD/CAA patients. These findings demonstrate the existence of potentially extensive and subtle functional diversity of C3+-reactive astrocytes.
A miniature optical extinction heated probe for fog droplet measurements in steam turbines
Authors: Bosdas Ilias , Mansour Michel , Kalfas Anestis I. , Abhari Reza S.
Published: March 2022

The knowledge of droplet size distribution and concentration allows us to calculate the wetness fraction and the isentropic turbine efficiency as well as to provide significant data for erosion modeling. For that purpose, a miniature optical extinction probe with a diameter of 9.4mm was designed, manufactured and tested. The probe is equipped with a heater, which maintains all optical components of the probe clean from any water contamination. In this paper the matrix inversion algorithm is presented in order to calculate the droplet diameter and concentration out of the spectral turbidity measurements. An ultrasonic atomizer was characterized in terms of droplet size and concentration with an established Phase Doppler Anemometry (PDA) system in order to have a reference spray environment for the proof of concept of the newly developed probe. Measurements were performed and results have shown a good agreement between the PDA technique and the optical extinction probe at various axial locations from the nozzle exit of the droplet generator.
Optical and Hot-Film Measurements of the Boundary Layer Transition on a Naca Airfoil
Authors: Šimurda David , Hála Jindřich , Luxa Martin , Radnic Tomáš
Published: March 2022

This study explores the possibilities of identifying position of a boundary layer transition using hot film measurements complemented by classical optical methods i.e. interferometry and schlieren method. The subject of the measurement is a NACA 0010-64 airfoil with varying leading edge surface quality corresponding to smooth surface and rough surface with Ra ~ 50 and Ra ~ 100. Measurements are performed at several subsonic regimes and a transonic regime. Despite several shortcomings of the experimental setup, the method proved to be useful in providing information on the boundary layer transition. Measurements show that in the case of smooth leading edge, the onset of the boundary layer transition shifts upstream with increasing inlet Mach number and the major portion of the boundary layer is transitional. This is in accordance with other published results on the boundary layer transition on this kind of airfoils [1]. In all cases with the rough leading edge, the complete transition takes place on the rough portion of the surface already.
A New Test Facility for Advanced Testing of Variable Inlet Guide Vanes
Authors: Frank Roman G. , Wacker Christian , Niehuis Reinhard
Published: March 2022

Various experimental and numerical studies of advanced blade configurations for variable inlet guide vanes (VIGVs) were conducted during the past years. Nevertheless, experimental loss characteri-zations of VIGV blade designs vastly focused on the primary profile losses. Secondary flow losses as they occur in a real engine application were often neglected. For this reason, a new wind tunnel facility was erected and commissioned at the Bundeswehr University Munich to enable extensive investigations of application-oriented annular VIGV configurations at typical low subsonic Mach numbers. Five-hole probe field traverses are established by a probe traversing unit in the in-and outflow region of the VIGV. The requirements for a further extension of the applicable measuring techniques by optical methods is moreover provided. Thus, not only profile losses caused by the blades, but also secondary flow losses generated by blade-wall flow interactions and the open blade tips can be resolved in detail.
General principles of secondary active transporter function
Authors: Beckstein Oliver , Naughton Fiona
Published: March 2022

Transport of ions and small molecules across the cell membrane against electrochemical gradients is catalyzed by integral membrane proteins that use a source of free energy to drive the energetically uphill flux of the transported substrate. Secondary active transporters couple the spontaneous influx of a “driving” ion such as Na+ or H+ to the flux of the substrate. The thermodynamics of such cyclical non-equilibrium systems are well understood, and recent work has focused on the molecular mechanism of secondary active transport. The fact that these transporters change their conformation between an inward-facing and outward-facing conformation in a cyclical fashion, called the alternating access model, is broadly recognized as the molecular framework in which to describe transporter function. However, only with the advent of high resolution crystal structures and detailed computer simulations, it has become possible to recognize common molecular-level principles between disparate transporter families. Inverted repeat symmetry in secondary active transporters has shed light onto how protein structures can encode a bi-stable two-state system. Based on structural data, three broad classes of alternating access transitions have been described as rocker-switch, rocking-bundle, and elevator mechanisms. More detailed analysis indicates that transporters can be understood as gated pores with at least two coupled gates. These gates are not just a convenient cartoon element to illustrate a putative mechanism but map to distinct parts of the transporter protein. Enumerating all distinct gate states naturally includes occluded states in the alternating access picture and also suggests what kind of protein conformations might be observable. By connecting the possible conformational states and ion/substrate bound states in a kinetic model, a unified picture emerges in which the symporter, antiporter, and uniporter functions are extremes in a continuum of functionality. As usual with biological systems, few principles and rules are absolute and exceptions are discussed as well as how biological complexity may be integrated in quantitative kinetic models that may provide a bridge from the structure to function.
Solution-processed tin oxide thin film for normally-off hydrogen terminated diamond field effect transistor
Authors: He Shi , Chen Genqiang , Han Xinxin , Wang Wei , Chang Xiaohui , Li Qi , Zhang Qianwen , Wang Yan-Feng , Zhang Minghui , Zhu Tianfei , Wang Hong-Xing
Published: March 2022

The solution processed method has been wildly used in the thin film fabrication because of the advantages of low cost, high efficiency, large scale for production, and long-term stability. In this paper, a normally-off hydrogen-terminated diamond field-effect transistor (FET) has been realized by using a solution processed SnO2 (sp-SnO2) film as an insulator layer. X-ray photoelectron spectroscopy results demonstrated the stoichiometry of the sp-SnO2 film, which shows good insulator properties with leakage current density less than 2.1 × 10−5 A·cm−2 at gate voltages from −6.0 to 6.0 V. The drain–source current maximum, threshold voltage, extrinsic transconductance maximum, and effective mobility of the FET with a gate length of 10 μm are −17.6 mA·mm−1, −0.5 V, 5.7 mS·mm−1, and 41.3 cm2/V s, respectively. According to the capacitance voltage characteristic, the enhancement mode could be ascribed to the high positive fixed charge density in the sp-SnO2 film, which will repel the hole in the channel. This paper provides a simple method and a low temperature process to fabricate an insulator layer.
Multiparticle collision dynamics for ferrofluids
Authors: Ilg Patrick
Published: March 2022

Detailed studies of the intriguing field-dependent dynamics and transport properties of confined flowing ferrofluids require efficient mesoscopic simulation methods that account for fluctuating ferrohydrodynamics. Here, we propose such a new mesoscopic model for the dynamics and flow of ferrofluids, where we couple the multi-particle collision dynamics method as a solver for the fluctuating hydrodynamics equations to the stochastic magnetization dynamics of suspended magnetic nanoparticles. This hybrid model is validated by reproducing the magnetoviscous effect in Poiseuille flow, obtaining the rotational viscosity in quantitative agreement with theoretical predictions. We also illustrate the new method for the benchmark problem of flow around a square cylinder. Interestingly, we observe that the length of the recirculation region is increased, whereas the drag coefficient is decreased in ferrofluids when an external magnetic field is applied compared with the field-free case at the same effective Reynolds number. The presence of thermal fluctuations and the flexibility of this particle-based mesoscopic method provide a promising tool to investigate a broad range of flow phenomena of magnetic fluids, and the method could also serve as an efficient way to simulate solvent effects when colloidal particles are immersed in ferrofluids.
Excitation wavelength-dependent photoluminescence decay of single quantum dots near plasmonic gold nanoparticles
Authors: Sun Yonglei , Wang Yongchen , Zhu Hua , Jin Na , Mohammad Adnan , Biyikli Necmi , Chen Ou , Chen Kun , Zhao Jing
Published: March 2022

Changing the excitation wavelength is a simple but effective strategy to modulate the photophysical cha racteristics of colloidal quantum dots (QDs) near plasmonic nanostructures. It has been observed that the photoluminescence (PL) decay of QDs near plasmonic nanostructures differs when the excitation wavelength is varied, but the exact mechanism is still unclear today. Here, we studied the excitation wavelength dependence of the PL decay of CdSe/CdS core/shell QDs near plasmonic gold nanoparticles at the single QD level. With the aid of statistical science, we demonstrated that the PL decay of a single QD near gold nanoparticles is generally faster when the QD is excited spectrally close to the localized surface plasmon resonance of gold nanoparticles. This excitation wavelength dependence is mainly caused by the varied proportion of photons coming from biexciton emission, which is the result of different local electric field enhancement by gold nanoparticles upon excitation.
Flow behavior and microstructure evolution of Al-3.65Cu-0.98Li (wt%) alloy during hot deformation
Authors: Lin Hai-tao , Long Shuai , Wu Dao-xiang , Li Shi-shan , Zhou Yu-ting , Wang Shu-yan , Dai Qing-wei
Published: March 2022

The phenomenological constitutive model, processing map and microstructure evolution of Al-3.65Cu-0.98Li (wt%) alloy were studied by means of isothermal compression tests conducted on a Gleeble-3500 isothermal simulator in the temperature range of 350 °C−500 °C and strain rate range of 0.01 s−1–10 s−1 and EBSD. The strain compensated Arrhenius model describes the flow curves accurately with a relative error of 0.9898 and an average absolute relative error of 4.70%. The plastic capability was characterized by strain rate sensitivity index, and it has the positive relation with temperature and negative relation with strain rate. The processing map was constructed, the instable deformation window and optimal hot working window of this alloy was identified to be 350 ∼ 455 °C & 0.37 ∼ 10s−1 and 440 ∼ 500 °C & 0.01 ∼ 0.368s−1, respectively. Moreover, the dynamic recrystallization occurs more violently at lower strain rate, and most portion were transformed into substructure with increasing strain rate, which was nearly vanished at the strain rate of 10 s−1. The geometric necessary dislocation distributions under different temperatures and strain rates were analyzed. More uniform distributed dislocation cell structures were observed at high temperature with low strain rate conditions and intensive dislocation and more pileups occurs at the contrary conditions.
Effect of suspension parameters towards the fabrication of BSCCO films by electrophoretic deposition
Authors: Lv Fangxia , Li Jianqiang , Zhang Xu , Zhao Zipeng , Wang Wei
Published: March 2022

Superconductor Bi-Sr-Ca-Cu-O (BSCCO) thin films were fabricated on silver by electrophoretic deposition (EPD) method. By investigating the effects of solvents and I2 additives on the properties of suspension prepared of BSCCO powder, the particle charging mechanism is analyzed. Studying the effect of different solvents on the structure of BSCCO powder, isopropanol is the best dispersion solvent. Through the optimization of the I2 concentration, the results show that the optimal concentration of I2 is 0.08 mg ml−1. The processing parameters critically influencing the morphology of BSCCO films are identified and optimized to obtain uniform films with high packing density of BSCCO particles. After heated at 820 °C for 20 h, the smoothest surface morphology, high c-axis orientation, and highest critical temperature(Tc) of 82 K are obtained from the film prepared with optimized suspension.
Spontaneous coronary artery dissection, fibromuscular dysplasia, and biventricular stress cardiomyopathy: a case report
Authors: Blazak Penni L , Holland David J , Basso Thomas , Martin Josh
Published: March 2022

Background

Spontaneous coronary artery dissection (SCAD) is an important cause of acute coronary syndrome and is associated with fibromuscular dysplasia (FMD). The diagnosis of stress cardiomyopathy in patients with SCAD and FMD is uncommon, though an important consideration given the shared risk profile. Complications of severe left ventricular (LV) dysfunction associated with stress cardiomyopathy, such as LV thrombus, complicate the management of SCAD where anticoagulation is controversial in the context of SCAD-associated intramural haematoma.

Case summary

A 65-year-old female presented with non-ST elevation myocardial infarction with a recent diagnosis of hypertension but no other traditional cardiovascular risk factors. There was, however, a family history of early cardiac death from myocardial infarction affecting her mother. Echocardiography demonstrated severe biventricular dysfunction with circumferential akinesis of the mid to apical segments. Coronary angiography demonstrated type 2A SCAD involving the first diagonal artery. Cardiac magnetic resonance imaging (MRI) confirmed a diagnosis of stress cardiomyopathy with biventricular involvement, complicated by LV apical thrombus and a focal region of myocardial infarction. Vascular imaging confirmed the presence of FMD. Guideline-directed heart failure therapy in addition to clopidogrel and rivaroxaban was prescribed. Follow-up contrast echocardiography at six-weeks confirmed resolution of LV dysfunction and resolution of the LV thrombus with no adverse events.

Discussion

The dual diagnosis of SCAD and stress cardiomyopathy is uncommon. Cardiac MRI was useful for confirming the diagnosis of stress cardiomyopathy and the presence of LV thrombus, where anticoagulation may complicate the management of intramural haematoma in patients with concomitant SCAD and FMD.
Pulmonary vascular disease in pulmonary hypertension due to left heart disease: pathophysiologic implications
Authors: Omote Kazunori , Sorimachi Hidemi , Obokata Masaru , Reddy Yogesh N V , Verbrugge Frederik H , Omar Massar , DuBrock Hilary M , Redfield Margaret M , Borlaug Barry A
Published: March 2022

Aims

Pulmonary hypertension (PH) and pulmonary vascular disease (PVD) are common and associated with adverse outcomes in left heart disease (LHD). This study sought to characterize the pathophysiology of PVD across the spectrum of PH in LHD.

Methods and results

Patients with PH-LHD [mean pulmonary artery (PA) pressure >20 mmHg and PA wedge pressure (PAWP) ≥15 mmHg] and controls free of PH or LHD underwent invasive haemodynamic exercise testing with simultaneous echocardiography, expired air and blood gas analysis, and lung ultrasound in a prospective study. Patients with PH-LHD were divided into isolated post-capillary PH (IpcPH) and PVD [combined post- and pre-capillary PH (CpcPH)] based upon pulmonary vascular resistance (PVR <3.0 or ≥3.0 WU). As compared with controls (n = 69) and IpcPH-LHD (n = 55), participants with CpcPH-LHD (n = 40) displayed poorer left atrial function and more severe right ventricular (RV) dysfunction at rest. With exercise, patients with CpcPH-LHD displayed similar PAWP to IpcPH-LHD, but more severe RV–PA uncoupling, greater ventricular interaction, and more severe impairments in cardiac output, O2 delivery, and peak O2 consumption. Despite higher PVR, participants with CpcPH developed more severe lung congestion compared with both IpcPH-LHD and controls, which was associated lower arterial O2 tension, reduced alveolar ventilation, decreased pulmonary O2 diffusion, and greater ventilation-perfusion mismatch.

Conclusions

Pulmonary vascular disease in LHD is associated with a distinct pathophysiologic signature marked by greater exercise-induced lung congestion, arterial hypoxaemia, RV–PA uncoupling, ventricular interdependence, and impairment in O2 delivery, impairing aerobic capacity. Further study is required to identify novel treatments targeting the pulmonary vasculature in PH-LHD.
Colistin-resistant Enterobacterales among veterinary healthcare workers and in the Dutch population
Authors: Dierikx C. M. , Meijs A. P. , Hengeveld P. D. , van der Klis F. R. M. , van Vliet J. , Gijsbers E. F. , Rozwandowicz M. , van Hoek A. H. A. M. , Hendrickx A. P. A. , Hordijk J. , Van Duijkeren E.
Published: March 2022

Objectives

Plasmid-mediated colistin resistance can be transferred from animals to humans. We investigated the prevalence of carriage of mcr-mediated colistin-resistant Escherichia coli and Klebsiella pneumoniae (ColR-E/K) in veterinary healthcare workers and in the general population in the Netherlands.

Methods

Two cross-sectional population studies were performed: one among veterinary healthcare workers and one in the general population. Participants sent in a faecal sample and filled in a questionnaire. Samples were analysed using selective enrichment and culture. Mobile colistin resistance genes (mcr) were detected by PCR and ColR-E/K were sequenced using Illumina and Nanopore technologies.

Results

The prevalence of mcr-mediated ColR-E/K was 0.2% (1/482, 95% CI 0.04%–1.17%) among veterinary personnel and 0.8% (5/660, 95% CI 0.3%–1.8%) in the population sample. mcr-1 was found in E. coli from four persons, mcr-8 in K. pneumoniae from one person and another person carried both mcr-1 and mcr-8 in a K. pneumoniae isolate. mcr-1 was found on different plasmid types (IncX4, IncI1 and IncI2), while mcr-8 was found on IncF plasmids only.

Conclusions

mcr-mediated ColR-E/K resistance was uncommon in both populations. Professional contact with animals does not increase the chance of carriage of these bacteria in the Netherlands at present. mcr-8 was found for the first time in the Netherlands. Surveillance of colistin resistance and its underlying mechanisms in humans, livestock and food is important in order to identify emerging trends in time.
Characterization of the AARTFAAC-12 aperture array: radio source counts at 42 and 61 MHz
Authors: Shulevski A , Franzen T M O , Williams W L , Vernstrom T , Gehlot B K , Kuiack M , Wijers R A M J
Published: March 2022

Dense aperture arrays provide key benefits in modern astrophysical research. They are flexible, employing cheap receivers, while relying on the ever more sophisticated compute back end to deal with the complexities of signal processing required for optimal use. Their advantage is that they offer very large fields of view and are readily scalable to any size, all other things being equal. Since they represent ‘software telescopes’, the science cases these arrays can be applied to are quite broad. Here, we describe the calibration and performance of the AARTFAAC-12 instrument, which is composed of the twelve centrally located stations of the LOFAR array. We go into the details of the data acquisition and pre-processing, we describe the newly developed calibration pipeline as well as the noise properties of the resulting images and present radio source counts at 41.7 MHz and 61 MHz. We find that AARTFAAC-12 is confusion limited at 0.9 Jy/PSF at 61 MHz with a PSF size of 17 × 11 arcmin and that the normalized source counts agree with the scaled VLSSr and 6C survey counts. The median spectral index of the sources between the two frequencies we observed at is -0.78. Further, we have used the derived source counts to estimate any excess cosmic radio background, and we do not find evidence for it at our observing frequencies compared to published literature values.
The Fix is in? Parliamentary Scrutiny of Appointments of the Heads of Brazilian Regulatory Agencies
Authors: Lopes André Vaz , Vieira Diego Mota
Published: March 2022

This manuscript analyses the parliamentary scrutiny of the presidential appointments to the direction of independent Brazilian Regulatory Agencies from an in-depth case study of the heads of the Brazilian Health Regulatory Agency—ANVISA, between 1999 and 2021. In Brazil, the Senate has the final decision on these appointments, exercising a dual function: parliamentary control over presidential patronage and selecting future heads of agencies. The objective of this article was to explain how the parliament exercises these functions and interferes in the appointment process. The results indicate that, although the formal process of parliamentary scrutiny seems like a game of marked cards, where it is already known in advance that the result will be approval, the Parliament plays an anticipatory role of presidential decisions, interfering in the timing of appointments and the possibility of influence over the choice of nominees.