bluuebunny/crossref_metadata_2025 huggingface dataset:
Design, Synthesis, and Screening of Pyridothieno[3,2-b]indole and Pyridothieno[3,2-c]cinnoline Derivatives as Potential Biologically Active Molecules
Authors: Stroganova Tatyana A. , Vasilin Vladimir K. , Kanishcheva Eugeniya A. , Dmitrieva Irina G. , Taranenko Viktor V. , Tumskiy Roman S. , Tumskaia Anastasiia V. , Aksenov Nikolay A. , Krapivin Gennady D.
Published: March 2022

New pyridothieno[3,2-b]indole and pyridothieno[3,2-c]cinnoline derivatives are designed and prepared from the corresponding 3-amino-2-arylthieno[2,3-b]pyridines. By a molecular docking method novel potential inhibitors of DNA gyrase B are identified among the thieno[2,3-b]pyridine derivatives. In addition, some of the prepared pyridothienoindoles exhibit in vivo antidote activity against the herbicide 2,4-D.
Reducing Alarm Fatigue in Maternal Monitoring on Labor and Delivery: A Commentary on Deimplementation in Obstetrics
Authors: Kern-Goldberger Adina R. , Hamm Rebecca F. , Raghuraman Nandini , Srinivas Sindhu K.
Published: March 2022

Hospital labor and delivery floors frequently operate like intensive care units (ICUs)—with continuous data feeds pouring into central monitoring stations against a background of blaring alarms. Yet the majority of obstetric patients are healthy and do not require ICU-level care. Despite limited organizational recommendations guiding the frequency of vital sign measurement, continuous pulse oximetry is used widely for laboring patients. There is also no evidence that morbidity prevention is linked to specific frequencies of vital sign monitoring in low-risk patients. In fact, studies examining the performance of maternal early warnings systems based on vital signs suggest that these may not reliably provide actionable information regarding maternal physiologic status. Furthermore, it is very possible that intrapartum maternal overmonitoring can impact care negatively by generating alarm fatigue, causing providers to miss actual abnormal vital signs that may precede morbidity.

Key Points
A Randomized Control Trial of Meditation for Mothers Pumping Breastmilk for Preterm Infants
Authors: Massa Katherine , Ramireddy Soumya , Ficenec Sara , Mank Carolyn , Josephsen Justin , Babbar Shilpa
Published: March 2022

Objective Mothers of preterm infants face unique challenges in establishing milk supply. We hypothesized that daily meditation practice while pumping would increase milk volume.

Study Design This was a randomized control trial examining the effect of meditation on the breastmilk supply of women delivering preterm infants. The meditation group engaged in daily use of a mindfulness-focused meditation app in addition to routine lactation support. The primary outcome was mean breastmilk volume on the infant's nineth day of life. Secondary outcomes included use of lactation-promoting behaviors, continuation of breastfeeding, and measures of mental health and breastfeeding self-efficacy by validated questionnaires. In addition to the intention to treat analysis, a per protocol analysis examined the association of frequent meditation with these breastfeeding and mental health outcomes.

Results A total of 60 women were analyzed. Mean milk volume was 647.1 ± 467.8 mL in the meditation group and 514.9 ± 393.5 mL in the routine care group (p = 0.27). Median number of pumping sessions was 7 (interquartile range [IQR] 5–8) in the meditation group, compared to 6 (IQR 4–7) in the routine care group (p = 0.11). Other lactation-promoting behaviors, breastfeeding continuation, and questionnaire scores were similar.

Adjusting for confounders, we found an increase in breastmilk production of 223.2 mL (95% CI 98.8–347.5, p = 0.001) and in pumping episodes by 0.93 (95% CI 0.16–1.70, p = 0.020) associated with frequent meditation. Skin-to-skin contact was increased to 100% (p = 0.006) among women who meditated seven or more times. Adjusted odds of a clinically significant Edinburgh Postnatal Depression Scale score of >9 was 0.057 (95% CI 0.0014–0.711, p = 0.023) with frequent meditation.

Conclusion Breastmilk production was similar in mothers practicing meditation compared to those receiving routine lactation support. For women engaging in frequent mediation, there may be an effect in establishing breastmilk supply and reduction of depression symptoms.

Key Points
Peculiarities of Atypical Meningiomas: Literature Review
Authors: Santos Rafael Rodrigues Pinheiro dos , Rampazzo Ana Carla Mondek , Zicarelli Carlos Alexandre Martins , Camargo Leonardo Valente de
Published: March 2022

Introduction Meningiomas are common tumors of the central nervous system that represent around 30% of primary tumors. However, the incidence of atypical meningiomas (AMs) is lower, of approximately 15% of all meningiomas, and they present high rates of relapse and mortality.

Aim To review peculiarities of AMs.

Methodology A literature review of articles published in English between 2009 and 2020 on the PubMed and Biblioteca Virtual em Saúde (BVS) databases using the terms meningioma and atypical.

Results Atypical meningiomas are rare and more prevalent in older males. The clinical condition depends on the site of the tumor, and a definitive diagnosis of AM is only possible via anatomical pathology. Moreover, prominent studies have indicated a relationship between the presence of the anti-Ki67 antibody/mindbomb (Ki-67/MIB1) marker as an aid in the definition of AM and one of the determinants of tumor aggressiveness. Imaging studies have also advanced in terms of seeking criteria using magnetic resonance that may suggest the malignancy of a lesion. As far as treatment is concerned, total resection remains the main therapeutic option, and it has a direct relationship with survival and time until disease progression. Lastly, there are many factors involved in the prognosis of AM.

Conclusion Atypical meningiomas continue to be a challenge, requiring further and more specific studies to provide a better understanding of it.
Neurodevelopmental Outcomes of Neonatal Rotavirus-Associated Leukoencephalopathy
Authors: Cho Jae Young , Yeom Jung Sook , Kim Young-Soo , Choi Dae-Seob , Park Ji Sook , Park Eun Sil , Seo Ji-Hyun , Lim Jae-Young , Woo Hyang-Ok , Park Chan-Hoo
Published: March 2022

Rotavirus infection has been reported to be associated with neonatal seizures with a diffuse and symmetrical diffusion restriction of periventricular white matter, namely, neonatal rotavirus-associated leukoencephalopathy. The extensive white matter injury seen in this cohort raises concerns about the long-term neurodevelopmental outcomes. In the present study, we prospectively assessed the neurodevelopmental outcomes of 13 patients with neonatal rotavirus-associated leukoencephalopathy at a median age of 26 months (range, 23–68 months). Neurodevelopmental outcomes were evaluated using a neurological examination, developmental evaluations, and magnetic resonance imaging (MRI) of the brain. Overall, 6 of the 13 patients (46%) had abnormal neurodevelopmental outcomes: 1 patient had mental retardation, visual–motor integration (VMI) dysfunction, cerebral palsy, and epilepsy; 1 patient had cerebral palsy and VMI dysfunction; remaining 4 patients had VMI dysfunction. Follow-up MRI in 12 of 13 patients showed an increased signal intensity on periventricular white matter in all patients. These findings suggested that neonatal rotavirus-associated leukoencephalopathy could not be assumed to be benign in long-term neurodevelopment, particularly in VMI function. Early intervention and long-term follow-up are necessary for these patients. Our findings raise caution for rotavirus infection in this vulnerable population for infants.
Building a Learning Health System: Creating an Analytical Workflow for Evidence Generation to Inform Institutional Clinical Care Guidelines
Authors: Dash Dev , Gokhale Arjun , Patel Birju S. , Callahan Alison , Posada Jose , Krishnan Gomathi , Collins William , Li Ron , Schulman Kevin , Ren Lily , Shah Nigam H.
Published: March 2022

Background One key aspect of a learning health system (LHS) is utilizing data generated during care delivery to inform clinical care. However, institutional guidelines that utilize observational data are rare and require months to create, making current processes impractical for more urgent scenarios such as those posed by the COVID-19 pandemic. There exists a need to rapidly analyze institutional data to drive guideline creation where evidence from randomized control trials are unavailable.

Objectives This article provides a background on the current state of observational data generation in institutional guideline creation and details our institution's experience in creating a novel workflow to (1) demonstrate the value of such a workflow, (2) demonstrate a real-world example, and (3) discuss difficulties encountered and future directions.

Methods Utilizing a multidisciplinary team of database specialists, clinicians, and informaticists, we created a workflow for identifying and translating a clinical need into a queryable format in our clinical data warehouse, creating data summaries and feeding this information back into clinical guideline creation.

Results Clinical questions posed by the hospital medicine division were answered in a rapid time frame and informed creation of institutional guidelines for the care of patients with COVID-19. The cost of setting up a workflow, answering the questions, and producing data summaries required around 300 hours of effort and $300,000 USD.

Conclusion A key component of an LHS is the ability to learn from data generated during care delivery. There are rare examples in the literature and we demonstrate one such example along with proposed thoughts of ideal multidisciplinary team formation and deployment.
Management of Hearing Loss in Infants: The UTD/Callier Center Position Statement
Authors: Jerger Susan , Roeser Ross J. , Tobey Emily A.
Published: March 2022

As infants are being identified earlier and earlier by universal newborn hearing screening programs, there is a need to establish principles for professionals involved in habilitative processes. Recently, a panel of experts was convened for a 2–day conference entitled “Habilitative Issues for Infants with Hearing Loss,” the Bruton Conference on Audiology/ Communication Sciences, UTD/Callier Center for Communication Disorders. The purpose of this document was to summarize the panel’s discussions on habilitative principles, state- of-the-art practices, and future needs for infants with hearing loss.
Designing nonvolatile memory devices with improved retention and writability
Authors: Piccone Ashley
Published: March 2022

Spin transfer torque and an extra layer of material enhance magnetic random access memory capabilities
Experimental and theoretical advances push study of metastable cortical neural networks forward
Authors: Liebendorfer Adam
Published: March 2022

New observations show promise for better understanding a range of neural processes in several species, from stimulus coding to decision making.
Laser shock experiments prove insightful in high strain rate deformation
Authors: Green Leigh Ann
Published: March 2022

Simulated and experimental laser treatment of aluminum foils produces practical, comprehensive material characterization.
Research on a large opening and high flow rate piezoelectric pump with straight arm wheeled check valve
Authors: He Lipeng , Hou Yi , Hu Dianbin , Hu Renhui , Zhang Zheng , Cheng Guangming
Published: March 2022

Piezoelectric pumps are applied in cooling systems of microelectronic devices because of their small size. However, cooling efficiency is limited by the low flow rate. A straight arm wheeled check valve made of silica gel was proposed, which can improve the flow rate of piezoelectric pumps, solve the influence of glue aging on the sealing ability of a wheeled check valve, and reduce the size of piezoelectric pumps. This paper discusses the influence of the valve arm number (N = 2, 3, and 4), the valve arm width (W = 1.0, 1.2, and 1.4 mm), and the valve thickness (T = 0.6, 0.8, and 1.0 mm) on the flow rate characteristics of piezoelectric pumps. When valve opening rises, the flow rate increases. The simulation results show that valves with 2 valve arm number, 0.6 mm valve thickness, and 1.0 mm valve arm width have maximum valve opening. The experimental results show that piezoelectric pumps with different valve parameters have different optimal frequencies. In addition, the maximum flow rate is 431.6 ml/min at 220 V and 70 Hz. This paper provides a reference for the application of piezoelectric pumps in cooling systems.
Microfluidic generation of monodispersed Janus alginate hydrogel microparticles using water-in-oil emulsion reactant
Authors: Liu Yingzhe , Nisisako Takasi
Published: March 2022

Microparticles with uniform anisotropic structures are widely used in physical, chemical, and biological fields owing to their ability to combine multiple functions on a micro-scale. Here, a microfluidic emulsion-based external gelation method was demonstrated for the first time to produce monodisperse Janus calcium alginate (Ca-alginate) hydrogel microparticles consisting of two compartments. This approach provided a fast reaction condition under which we could prepare magnetic Janus Ca-alginate microparticles with diameters ranging from 148 to 179 μm and a coefficient of variation (CV) less than 4%. Moreover, the boundaries between the two compartments were clear. In addition, the volume fraction of each compartment could be adjusted by varying the flow rate ratio between two dispersed phases. Next, we produced fluorescent Janus beads and magnetic-fluorescent Janus beads with an average diameter of ∼150 μm (CV < 4.0%). The magnetic Janus hydrogel microparticles we produced could be manipulated by applying a magnetic field to achieve self-assembly, rotation, and accumulation. Magnetic Janus hydrogel microparticles are also capable of mammalian cell encapsulation with good cell viability. This article presents a simple and stable approach for producing monodisperse bi-compartmental Janus hydrogel microparticles that could have great potential for application in physical, biochemical, and biomedical fields.
Magnetohydrodynamic shock refraction at an inclined density interface
Authors: Chen Fang , Wheatley Vincent , Samtaney Ravi
Published: March 2022

Shock wave refraction at a sharp density interface is a classical problem in hydrodynamics. Presently, we investigate the strongly planar refraction of a magnetohydrodynamic (MHD) shock wave at an inclined density interface. A magnetic field is applied that is initially oriented either perpendicular or parallel to the motion of incident shock. We explore flow structure by varying the magnitude of the magnetic field governed by the non-dimensional parameter β∈(0.5,106) and the inclination angle of density interface α∈(0.30,1.52). The regular MHD shock refraction process results in a pair of outer fast shocks (reflected and transmitted) and a set of inner nonlinear magneto-sonic waves. By varying magnetic field (strength and direction) and inclination interface angle, the latter waves can be slow shocks, slow expansion fans, intermediate shocks, or slow-mode compound waves. For a chosen incident shock strength and density ratio, the MHD shock refraction transitions from regular (all nonlinear waves meeting at a single point) into irregular when the inclined density interface angle is less than a critical value. Irregular refraction patterns are not amenable to an analytical solution, and hence, we have obtained irregular refraction solutions by numerical simulations. Since the MHD shock refraction is self-similar, we further explore by converting the initial value problem into a boundary value problem (BVP) by a self-similar coordinate transformation. The self-similar solution to the BVP is numerically solved using an iterative method and implemented using the p4est adaptive mesh framework. The simulation shows that a Mach stem occurs in an irregular MHD shock refraction, and the flow structure can be an MHD equivalent to a single Mach reflection irregular refraction and convex-forwards irregular refraction that occur in hydrodynamic case. For Mach number M = 2, both analytical and numerical results show that perpendicular magnetics fields suppress the regular to irregular transition compared to the corresponding hydrodynamic case. As Mach number decreased, it is possible that strong perpendicular magnetics promote the regular to irregular transition, while moderate perpendicular magnetics suppress this transition compared to the corresponding hydrodynamic case.
Modeling of multi-edge effects in the case of laser shock loadings applied on thin foils: Application for material characterization of aluminum alloys
Authors: Ayad M. , Lapostolle L. , Rondepierre A. , Le Bras C. , Scius-Bertrand M. , Ünaldi S. , Trdan U. , Rouchausse Y. , Grassy J. , Maillot T. , Lapoujade V. , Michel C. , Berthe L.
Published: March 2022

This article presents the study of the shock wave propagation through aluminum alloys (pure aluminum and aluminum 2024-T3) produced by laser plasma using experimental and numerical tests. Water confinement regime interaction, pulse duration (7.2 ns), and power density (1–5 GW/cm2) range correspond to laser shock peening process configuration and parameters. To that scope, we simulate the shock wave propagation using non-linear explicit code LS-DYNA, which we validate with experimental results. Thereupon, we present a descriptive analysis that links separately the material model and loading conditions to the dynamic response of aluminum alloys under high strain rate laser shock by coupling the Johnson-Cook (J-C) material model with the Grüneisen equation of state (MAT_015 and EOS_GRUNEISEN accordingly). In addition, we make use of stress propagation into target thickness to analyze the origin of different points on the Back Face Velocity (BFV) profile during shock propagation. Finally, we provide evidence that 2D compressive effects do not depend only on the focal spot size or target thickness such as the edge effects but also on power density and material initial yield strength.
Investigation into the coherence of flame intensity oscillations in a model multi-element rocket combustor using complex networks
Authors: Kasthuri Praveen , Krishnan Abin , Gejji Rohan , Anderson William , Marwan Norbert , Kurths Jürgen , Sujith R. I.
Published: March 2022

Capturing the complex spatiotemporal flame dynamics inside a rocket combustor is essential to validate high-fidelity simulations for developing high-performance rocket engines. Utilizing tools from a complex network theory, we construct positively and negatively correlated weighted networks from methylidyne (CH*) chemiluminescence intensity oscillations for different dynamical states observed during the transition to thermoacoustic instability (TAI) in a subscale multi-element rocket combustor. We find that the distribution of network measures quantitatively captures the extent of coherence in the flame dynamics. We discover that regions with highly correlated flame intensity oscillations tend to connect with other regions exhibiting highly correlated flame intensity oscillations. This phenomenon, known as assortative mixing, leads to a core group (a cluster) in the flow-field that acts as a “reservoir” for coherent flame intensity oscillations. Spatiotemporal features described in this study can be used to understand the self-excited flame response during the transition to TAI and validate high-fidelity simulations essential for developing high-performance rocket engines.
Study of pulsed laser-induced heating in bio-plasmonic solution using combined photoacoustic and probe beam deflection technique: Thermoacoustic effects
Authors: Khosroshahi Mohammad E. , Patel Yesha , Woll-Morison Vaughan , Chabok Roxana
Published: March 2022

We describe studies of the interaction of a pulsed Nd:YAG laser with bovine serum albumin (BSA) solution (i.e., S0) and S0 containing gold nanourchin (GNU) (i.e., S1: S0 + 0.1 ml GNU) using combined photoacoustic (PA) and probe beam deflection (PBD) techniques. The changes in absorbance and chemical bonds are studied by UV–Vis and near-FTIR spectroscopy. The results showed a decrease in absorbance of the bio-plasmonic solution, which further decreased by increasing the concentration. The PA pressure increased with fluence in the order of GNU > S0 > S1, and all exhibited a non-linear response at ≈9.5 J cm−2and reached a maximum at 12.5 J cm−2. No PBD was observed in S0 indicating the role of GNU in producing the heating effect. ∂n/∂T increased in the order of S2 > S1 > S0, respectively, where S2 is (S0 + 0.2 ml GNU). The absorbance of S0 and S1 increased after heating due to protein denaturation. For S1, surface-enhanced FTIR showed an increase in the intensity of most bands between 6320 and 6630 cm−1, and the band at 5264 cm−1, which likely corresponds to β-sheet structure, significantly diminished after heating. The collapse of cavitation and plasma shock waves produced significant acoustic transients, hence some photomechanical effects. The acoustic energy released after the collapse of bubbles at 1.8 and 12.5 J cm−2was calculated to be ≈140  μJ and 7 mJ, respectively, corresponding to 4% and 28% of the input optical energy being converted to sound energy in the early phase of the expansion.
Reversible single cell trapping of Paramecium caudatum to correlate swimming behavior and membrane state
Authors: Schnitzler Lukas G. , Paeger Anne , Brugger Manuel S. , Schneider Matthias F. , Westerhausen Christoph
Published: March 2022

Single cell measurements with living specimen like, for example, the ciliated protozoan Paramecium caudatum can be a challenging task. We present here a microfluidic trapping mechanism for measurements with these micro-organisms that can be used, e.g., for optical measurements to correlate cellular functions with the phase state of the lipid membrane. Here, we reversibly trap single cells in small compartments. Furthermore, we track and analyze the swimming behavior of single cells over several minutes. Before and after reversible trapping the swimming speed is comparable, suggesting that trapping does not have a large effect on cell behavior. Last, we demonstrate the feasibility of membrane order measurements on living cells using the fluorescent dye 6-lauryl-2-dimethylaminonaphthalene (Laurdan).
Three-dimensional numerical simulation on near-field pressure evolution of dual-tube underwater detonation
Authors: Hou Zi-wei , Li Ning , Huang Xiao-long , Li Can , Kang Yang , Weng Chun-sheng
Published: March 2022

The detonation-powered underwater engine, with the advantages of high specific impulse, high speed, and simple structure, has very broad application prospects in the field of underwater propulsion, and dual-tube combination is an effective means to improve its propulsion performance. In this work, near-field pressure evolution of shock waves and high-pressure zones between two detonation tubes is numerically studied. The two-fluid model and three-dimensional conservation element and solution element method are adopted to reveal the formation, intersection, and interaction of shock waves. Detonation waves generated by two detonation tubes decouple into shock waves after penetrating into water and form a high-pressure zone near each tube exit. The two leading shock waves intersect with each other in the propagation, creating the second high-pressure zone between two tubes. Then, a propagating forward merged new shock wave covers the two original wave-fronts and maintains higher pressure. Pressure evolution under different tube intervals, ignition delays, and filling conditions is also presented to discuss their influence on the performance of dual-tube detonation. The intensity and directivity of shock waves are found to be sensitive to these factors, complexly affecting the thrust components, which provides a depth understanding of dual-tube combination in the application.
TbCu7-type Sm-X-Fe compounds (X = Zr, Hf, Y, Dy, La, Ce and Nd) synthesized by low-temperature reduction-diffusion (LTRD) process using molten salt
Authors: Kim Jungryang , Okada Shusuke , Takagi Kenta
Published: March 2022

TbCu7-type Sm-Fe-N anisotropic powder with a high Fe content has the potential to surpass the Nd-Fe-B magnet. In this study, elemental substitution of Sm in a Sm-Fe system was investigated for the purpose of synthesizing Fe-rich TbCu7-type Sm-Fe compounds using a low-temperature reduction-diffusion (LTRD) process, which is a synthesis method capable of producing TbCu7-type Sm-Fe-N anisotropic powder. Sm-X-Fe powders have been synthesized by mixing ɑ-Fe, SmCl3, one chloride of additives (X = Zr, Hf, Y, Dy, La, Ce and Nd), Ca, and LiCl, and performing the reduction-diffusion reaction at 600 °C. The results of an EDX analysis and the variation of a-axis lengths of the TbCu7-type Sm-X-Fe phase suggested that all additional elements could be substituted for Sm. Although the synthesis of Fe-rich TbCu7-type phase was not achieved in this study, substitution of Zr and Hf showed a potential to increase Fe content.
Poor welfare outcomes resulting from poor management decisions in a translocation of western grey kangaroos (Macropus fuliginosus)
Authors: Thompson Graham G. , Thompson Scott A. , Pusey Anthony
Published: March 2022

There is often considerable social media commentary on whether remnant kangaroo populations in urban areas should be euthanased or translocated. Here, we describe a translocation program in Western Australia where kangaroos were herded into a temporary enclosure, darted, sedated, and translocated to a site in the State Forest east of the Swan Coastal Plain where they were released after 24 h. Prior to darting and after being initially herded into a temporary holding enclosure, kangaroos were repeatedly released from the enclosure by members of the public. Sixty-three of 154 adult kangaroos and 20 of 52 pouched young (40.3%) died or were euthanased before being released from the translocation release enclosure. The total volume of the sedative Zoletil (mL kg−1) injected into kangaroos as a sedative was significantly higher in those that survived than those that died. The primary conclusion from this management program was that the western grey kangaroos were susceptible to capture myopathy and distressed animals are at a greater risk of not surviving a translocation program. In our professional judgement, from an animal welfare perspective, these kangaroos should have been euthanased and not translocated. Such scientific advice and professional experience should inform future decisions regarding management of remnant kangaroo populations.
Dual-function AzuCR RNA modulates carbon metabolism
Authors: Raina Medha , Aoyama Jordan J. , Bhatt Shantanu , Paul Brian J. , Zhang Aixia , Updegrove Taylor B. , Miranda-Ríos Juan , Storz Gisela
Published: March 2022

Significance

While most small, regulatory RNAs are thought to be “noncoding,” a few have been found to also encode a small protein. Here we describe a 164-nucleotide RNA that encodes a 28-amino acid, amphipathic protein, which interacts with aerobic glycerol-3-phosphate dehydrogenase and increases dehydrogenase activity but also base pairs with two mRNAs to reduce expression. The coding and base-pairing sequences overlap, and the two regulatory functions compete.
Autopsy Results from a COVID-19 Patient Treated in a Tropical Area, and a Review of the Epidemiological History
Authors: Cai Jie , Wang Bo , Song Tao , Zhang Peng , Long Ren , Liu Xiaoran , Deng Jianqiang , Chen Jianhua
Published: March 2022

Since the start of the COVID-19 pandemic, there has been an urgent need to produce accurate and sensitive tests. However, there have been instances where a positive nucleic acid test turns negative after treatment, and then positive again. This case report describes such an instance from the tropical region of Hainan, China. The patient was a 61-year-old female who went to Hainan on vacation from Wuhan during the COVID-19 pandemic in 2020. Symptoms appeared 9 d after arriving in Hainan, and it was confirmed that the nucleic acid test was positive after 4 repeats. Her condition declined rapidly, her heart stopped beating, and she was admitted in a coma to the ICU. After treatment, the SARS-CoV-2 virus nucleic acid test of several nasopharyngeal swabs were negative, and tests on whole blood, anal swabs, and urine were also negative. Later, however, nucleic acid tests on a lower respiratory tract sputum swab and lower respiratory tract lavage fluid were positive. An autopsy examination was carried out 12 h after her death, and multi-organ secretions were extracted for nucleic acid testing. The SARS-CoV-2 virus nucleic acid was only detected in the swabs from the end of the bronchus, which was confirmed by the visualization of the coronavirus by electron microscopy. Autopsy confirmed that the damage was mainly concentrated in the lungs and immune organs and tissues throughout the body. Epidemiology indicated that none of the people she came into contact with after arriving in Hainan, including close contacts, were infected. This is in sharp contrast to the highly contagious virus in Wuhan in the temperate zone during the same period. This case report indicates: (1) The high temperatures in tropical areas may have an impact on the spread and harm of COVID-19, and (2) The reason why nucleic acid testing for COVID-19 was initially negative and then positive after treatment may be related to the survival of the SARS-CoV-2 virus in deep lung tissues.
The aryl hydrocarbon receptor contributes to tissue adaptation of intestinal eosinophils in mice
Authors: Diny Nicola Laura , Schonfeldova Barbora , Shapiro Michael , Winder Matthew L. , Varsani-Brown Sunita , Stockinger Brigitta
Published: March 2022

Eosinophils are potent sources of inflammatory and toxic mediators, yet they reside in large numbers in the healthy intestine without causing tissue damage. We show here that intestinal eosinophils were specifically adapted to their environment and underwent substantial transcriptomic changes. Intestinal eosinophils upregulated genes relating to the immune response, cell–cell communication, extracellular matrix remodeling, and the aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor with broad functions in intestinal homeostasis. Eosinophils from AHR-deficient mice failed to fully express the intestinal gene expression program, including extracellular matrix organization and cell junction pathways. AHR-deficient eosinophils were functionally impaired in the adhesion to and degradation of extracellular matrix, were more prone to degranulation, and had an extended life span. Lack of AHR in eosinophils had wider effects on the intestinal immune system, affecting the T cell compartment in nave and helminth-infected mice. Our study demonstrates that the response to environmental triggers via AHR partially shapes tissue adaptation of eosinophils in the small intestine.
Direct calibration method of effective wavelength for fiber-optic multi-wavelength pyrometer based on optimization function
Authors: Liang Mei , Wang Yongsheng , Wang Changhui , Wang Yantao
Published: March 2022

The calibration of the temperature and effective wavelength must be carried out before multi-wavelength pyrometers application. The current calibration method of the effective wavelength for the multi-wavelength pyrometers is the pyrometer wavelength function (PWF) method. However, for the actual calibration of the fiber-optic multi-wavelength pyrometer, the signal is too weak to obtain effective wavelength by the PWF. Therefore, a new calibration method based on optimization function for effective wavelength is proposed in this paper. The core idea of the innovation is to transform the effective wavelength calibration into an optimization problem, in which the effective wavelength can be solved directly by the MATLAB software using the temperature calibration data. Comparing with the PWF, the presented new method not only provides a novel way to obtain effective wavelength, but also avoids time-consuming due to the complicated process from the wavelength calibration. Finally, simulation and experimental results verify that the proposed method is effectiveness by using the function fmincon and minconPS from MATLAB software, in which the fmincon function is superior to the minconPS function for the efficiency and anti-noise performance.
Adaptive surge detection of magnetic suspension centrifugal blower based on rotor radial displacement signal and SOGI-FLL with prefilter
Authors: Guan Xudong , Zhou Jin , Jin Chaowu , Wu Haitong , Lin Yingzhe
Published: March 2022

For the surge detection problem of high-speed magnetic suspension centrifugal blower, a second order generalized integral-frequency locked loop with prefilter (SOGI-FLL-WPF) is used for surge detection. This method is utilized to normalize the amplitude and frequency of the surge signal by using the rotor radial displacement signal in the magnetic suspension blower. So that the response speed of detecting surge signal is not affected by the frequency and amplitude, and the frequency of the blower surge vibration signal is tracked adaptively. As a result, the fast response ability of the surge signal detection is improved. Specifically, firstly, the rotor radial displacement signal is collected in real time. And then, the rotor speed is identified by SOGI-FLL, and the identified speed information is input to SOGI for notch. Finally, the surge detection is carried out by SOGI-FLL-WPF for the signal after notch. The 105 kW magnetic suspension centrifugal blower is applied for the surge detection experiment. The experimental results show that the surge detection method based on rotor radial displacement signal and SOGI-FLL-WPF can detect the surge signal immediately after its occurrence. The proposed detection method needs no additional detection unit, and has the advantages of simple algorithm, fast response speed and small amount of calculation. In addition, it can effectively reflect the change of frequency in the process of surge.
Site and bond percolation on four-dimensional simple hypercubic lattices with extended neighborhoods
Authors: Zhao Pengyu , Yan Jinhong , Xun Zhipeng , Hao Dapeng , Ziff Robert M
Published: March 2022

The asymptotic behavior of the percolation threshold p

c
and its dependence upon coordination number z is investigated for both site and bond percolation on four-dimensional lattices with compact extended neighborhoods. Simple hypercubic lattices with neighborhoods up to 9th nearest neighbors are studied to high precision by means of Monte-Carlo simulations based upon a single-cluster growth algorithm. For site percolation, an asymptotic analysis confirms the predicted behavior zp

c
∼ 16η

c
= 2.086 for large z, and finite-size corrections are accounted for by forms p

c
∼ 16η

c
/(z + b) and p

c
∼ 1 − exp(−16η

c
/z) where η

c
≈ 0.1304 is the continuum percolation threshold of four-dimensional hyperspheres. For bond percolation, the finite-z correction is found to be consistent with the prediction of Frei and Perkins, zp

c
− 1 ∼ a
1(ln z)/z, although the behavior zp

c
− 1 ∼ a
1
z
−3/4 cannot be ruled out.
Development of an on-chip configurable DAC module for monolithic active pixel sensor
Authors: Tian Y. , Yang P. , Wang Q. , Zhou W. , Niu X. , Huang J. , Zhao C.
Published: March 2022

This paper describes an on-chip configurable Digital to Analog Converter (DAC) module for monolithic active pixel sensor. The DAC module consists of four 10-bit voltage DACs, seven 8-bit current DACs, a bandgap circuit, and a configure interface. The voltage DAC is implemented with an R-2R resistor ladder network, and each LSB corresponds to 3 mV. The current DAC is in the current-steering type with a thermometer code. Each LSB of the current DAC corresponds to 10 nA. The bandgap circuit provides a stable, temperature-independent reference voltage of 1.25 V to the DACs. All the DACs can be accessed and configured with the configure interface. The DAC module covers 3074 µm × 400 µm, and the total power consumption is 46.2 mW. This paper will discuss the design and performance of this DAC module.
A flexible and low-cost open-source IPMC mezzanine for ATCA boards based on OpenIPMC
Authors: Calligaris L. , Cascadan A. , Ardila-Perez L.E. , Pesaresi M. , Fedi G. , Peck A. , Gastler D.
Published: March 2022

This work presents the development of an Intelligent Platform Management Controller mezzanine in a Mini DIMM form factor for use in electronic boards compliant to the PICMG Advanced Telecommunication Computing Architecture (ATCA) standard. The module is based on an STMicroelectronics STM32H745 microcontroller running the OpenIPMC open-source software. The mezzanine has been successfully tested on a variety of ATCA boards being proposed for the upgrade of the experiments at the HL-LHC, with its design and firmware being distributed under open-source hardware license.
Tree mortality in a warming world: causes, patterns, and implications
Authors: Yi Chuixiang , Hendrey George , Niu Shuli , McDowell Nate , Allen Craig D
Published: March 2022

This ERL focus collection has published 17 papers that have advanced our understanding of different dimensions of warming-induced tree mortality. Here we summarize these focus collection papers, organized by four topics related to tree mortality: pathogens, droughts/heat waves, fire/bark beetles, and teleconnections/air pollution. This focus collection illustrates a variety of methods in measuring and modeling tree-mortality, and adds significant new research findings into the scientific literature on tree mortality from hotter droughts. Some of these results also are useful for policymakers and forest managers in addressing amplified forest stress and tree mortality as a result of increasingly severe warming-induced climate and weather extremes.
A CMIP6 assessment of the potential climate change impacts on solar photovoltaic energy and its atmospheric drivers in West Africa
Authors: Danso Derrick Kwadwo , Anquetin Sandrine , Diedhiou Arona , Lavaysse Christophe , Hingray Benoit , Raynaud Damien , Kobea Arsène Toka
Published: March 2022

Many solar photovoltaic (PV) energy projects are currently being planned and/or developed in West Africa to sustainably bridge the increasing gap between electricity demand and supply. However, climate change will likely affect solar power generation and the atmospheric factors that control it. For the first time, the state-of-the-art CMIP climate models (CMIP6) are used to investigate the potential future evolution of solar power generation and its main atmospheric drivers in West Africa. A multi-model analyses carried out revealed a decrease of solar PV potential throughout West Africa in the 21st century, with an ensemble mean reduction reaching about 12% in southern parts of the region. In addition, the variability of future solar PV production is expected to increase with a higher frequency of lower production periods. The projected changes in the solar PV production and its variability are expected to be predominant in the June to August season. We found the decrease in the solar PV potential to be driven by a decrease of surface irradiance and an increase of near-surface air temperature. However, the decrease of the surface irradiance accounted for a substantially larger percentage of the projected solar PV potential. The decrease in surface irradiance was further linked to changes in both cloud cover and aerosol presence, although generally much more strongly for the former.
Comparative investigation on thermally sprayed Al2O3, Al2O3–13%(TiO2) and Al2O3–40%(TiO2) composite coatings from room to 400 °C temperature
Authors: Kumar Deepak , Murtaza Qasim , Walia R S , Singh Pushpendra
Published: March 2022

In the present study, three coatings of Al2O3, Al2O3–13%(TiO2) and Al2O3–40%(TiO2) composite coatings were deposited by the thermally flame spray process. The comparative wear behaviour of the Al2O3–TiO2 coatings has been studied under high temperature levels up to 400 °C with the help of a high temperature tribometer at a constant load of 40N. Prior to the tribo-test, the coating morphology and elemental analysis has been examined with the help of field emission scanning electron microscope (FESEM), elemental dispersion spectroscopy (EDS) and x-ray powder diffraction (XRD) techniques. The mechanical properties have been also analyzed and reported. The results reveal that specific wear rate decreases with an increase in temperature for all the deposited coating except Al2O3 coating at 400 °C. The overall friction coefficient of the coatings is decreasing with the increasing temperature. The Al2O3–40%TiO2 coating showed maximum sustainability against wear as well as a low coefficient of friction because of its low hardness and high adhesion properties. The examined worn surface validates the presence of brittle fracture and abrasive wear behaviour mechanism along with the oxidation wear, from room temperature to 400 °C.
Effect of Al content on microstructure and wear properties of FeCrNiMnAlx high-entropy alloys
Authors: Xing Xuewei , Liu Ying , Hu Jinkang , Li Wei
Published: March 2022

A series of FeCrNiMnAlx (x = 0, 0.3, 0.5, 0.8, 1.0 in molar ratio) high entropy alloys (HEAs) were prepared by the vacuum arc melting method. The effects of Al content on the microstructure, mechanical and wear properties were investigated. For FeCrNiMn alloy, the microstructure was main homogeneous structure with face-centered cubic (FCC) phase, whilst FeCrNiMnAl0.3 produced a dendritic microstructure consisting of a mixture of FCC + BCC + B2 phases, and the mixture BCC + B2 dendritic interdendritic microstructure appeared when the molar ratio of Al is beyond 0.5. The hardness and yield stress of the HEAs are effectively improved with the increased Al amount but the ductility is lowered. In this case, FeCrNiMnAl alloy showed decreased yield stress due to the deteriorated ductility. Moreover, the friction coefficient decreases, and the wear resistance improved with the increased aluminum content. FeCrNiMnAl0.8 HEAs have the best wear resistance due to the advantages of achieving a balance of strength and ductility.
NASA celebrates JWST deployment
Authors: Banks Michael
Published: March 2022

The James Webb Space Telescope has completed a series of daring manoeuvres as it moves closer to becoming an operational observatory, as Michael Banks finds out.
Scientists release feasibility study for an interstellar probe
Authors: Kruesi Liz
Published: March 2022

A feasibility study by space scientists suggests a mission to travel deep into interstellar space could be designed, built and launched by the mid-2030s.
Charles Lieber found guilty over China links
Authors: Gwynne Peter
Published: March 2022

Nanotechnology researcher Charles Lieber from Harvard University has been found guilty on six charges related to his connection with the Wuhan University of Technology.
Physics on the cheap
Authors: Crease Robert P
Published: March 2022

The simplest questions are often the best. Robert P Crease tries to answer one from a physics student in Kenya.
Up the spout
Authors: Beddows John
Published: March 2022

In response to the Quanta article “Dribbling teapots revisited”, which reports that researchers say they have developed a “complete” theory describing tea dribbling down the outside of a teapot’s spout.
Laughing in the face of danger
Authors: Hiscott Laura
Published: March 2022

Laura Hiscott reviews the film Don’t Look Up, directed by Adam McKay and available now on Netflix.
Nitrogen driven niche differentiation in bacterioplankton communities of northeast coastal Bay of Bengal
Authors: Ghosh Anwesha , Woodward E Malcolm S , Saha Ratul , Nelson Craig E , Bhadury Punyasloke
Published: March 2022

The Bay of Bengal receives nitrogen inputs from multiple sources and the potential role of nitrogen-metabolizing microbial communities in the surface water is not well understood. The nitrogen budget estimate shows a deficit of 4.7 ± 2.4 Tg N yr-1, suggesting a significant role of dissolved organic nitrogen remineralization in fuelling ecosystem processes. Unravelling the process of remineralization leading to increasing concentrations of dissolved inorganic nitrogen (DIN) in coastal ecosystems such as in mangroves require a better understanding of the composition of functional resident bacterioplankton communities. Bacterioplankton communities were elucidated from eight stations along different estuaries spanning west to east of northeast coastal Bay of Bengal to understand the influence of DIN on shaping these communities. The eight stations were differentiated into ‘low’ and ‘high’ DIN stations based on DIN concentration, with five stations with High DIN concentration (>45 μM) and three stations with Low DIN concentration (<40μM). The V3–V4 region of 16S rRNA was amplified and sequenced to elucidate resident bacterioplankton community structure from environmental DNA. Proteobacteria, Bacteroidetes, and Firmicutes were the dominant bacterioplankton phyla across all stations. Nitrogen-fixing groups such as Nitrospirae, Lentisphaerae, Chloroflexi, and Planctomycetes make up about 1% of the bacterioplankton communities. Abundances of Spirochaetes and Tenericutes showed a positive correlation with DIN. Pseudomonadales, Alteromonadales, and Desulfovibrionales were found to distinctly vary in abundance between Low and High DIN stations. Predicted metagenomic profiles from taxonomically derived community structures indicated bacterial nitrate-nitrite reductase to be negatively correlated with prevalent DIN concentration in High DIN stations but positively correlated in Low DIN stations. This trend was also consistent for genes encoding for nitrate/nitrite response regulators and transporter proteins. This indicates the need to delineate functional bacterioplankton community structures to better understand their role in influencing rates and fluxes of nitrogen within mangroves.
Influence of water absorption on the mechanical behavior of CFRPs manufactured by RTM at room temperature
Authors: Kim Eunjung , Jung Doyun , Yu Woong-Ryeol , Na Wonjin
Published: March 2022

Deterioration of the physical properties of fiber-reinforced composites is inevitable under a high temperature and humidity environment. The resin transfer molding (RTM) process for large composite parts is often accompanied by micropore formation, making the composite more sensitive to water absorption. In this study, carbon fiber-reinforced composite specimens were manufactured using the RTM process at room temperature, and their water absorption and mechanical properties were investigated. The water absorption was saturated after about 40 d, and the absorption ratio was higher at 75 °C than at 50 °C. The tensile strength of water-soaked specimens was decreased by 15%, exhibiting interlaminar delamination. However, plasticization of the cured epoxy resin by water increased interlaminar fracture toughness. These results indicate that water absorption accelerated interlaminar cracking initiated by micropore and interfacial failure in toughened resin, especially under low-temperature curing condition.