bluuebunny/crossref_metadata_2025 huggingface dataset:
Central Nervous System Involvement in Dengue Virus Type 1 Infection: A Pediatric Case Series
Authors: Pattrakornkul Nalinee , Siriboriruk Jukrapun
Published: August 2022

Central nervous system involvement accounted for 0.5 to 21.2% of dengue virus infections. Dengue virus type 2 and type 3 were commonly found in patients with central nervous system manifestations, while dengue virus type 1 (DENV-1) was rarely reported. We reported three dengue fever cases with neurological complications associated with DENV-1 infection. A previously healthy boy presented with fever, agitation, and an altered mental status in the first case. The other two cases presented with fever and seizures. All of them had no plasma leakage from dengue infection. DENV-1 was detected by reverse transcriptase-polymerase chain reaction assay in cerebrospinal fluid, serum, or both. All three cases were resolved entirely without neurological sequelae. This study can alert hospitals to prepare for the next epidemic in which there could be increasing cases of unusual or severe manifestations of dengue.
Doxycycline: An Antibiotic Attenuates Oxidant Stress, Perturbation of Lipid Metabolites, and Antioxidants against Vanadium Toxicity in Rat Hepatocytes
Authors: Gassar Ezeddin Salem , Mohamed Negia Abdullah Emtawel , Emtawel Fatema Abdullah , Elfakhri Rehab M. , Haider Syed Saleem
Published: August 2022

Background The liver is target following exposure to pentavalent vanadium (V5+). Doxycycline is an antioxidant that prevents the progression of disease through inhibition of lipid peroxidation.

Aim The present study was designed to evaluate the protective effects of doxycycline against vanadium-induced hepatoxicity.

Methods Sixty two male Sprague-Dawley rats (250–300 g) were equally divided into the following four groups: control group (received 0.2 mL of physiological saline), doxycycline control group (received 4 mg/kg body weight on day 1 and 2 mg/kg body weight daily thereafter), vanadium group (received elemental vanadium 1.5 mg/kg-body weight in distilled water), and concomitantly treated group (doxycycline + vanadium) received (doxycycline 4 mg/kg body weight on day 1 and 2 mg/kg body weight thereafter + vanadium 1.5 mg/kg body weight), all given orally for 10 consecutive days. The rats were sacrificed by decapitation 24 hours after the last dose. The liver was removed rapidly and processed for the evaluation of metabolic variables: phospholipids, cholesterol, cerebrosides, gangliosides, reduced glutathione (GSH), vitamin C, calcium, acetylcholinesterase enzyme, and lipid peroxidation.

Results Vanadium administration significantly reduced (−60 g) the body weight and significantly increased (+28%) the relative liver weight compared with controls. The rats exhibited neurological function deficits. Vanadium administration decreased the concentrations of metabolic variables compared with controls, cerebrosides (−50%), cholesterol (−39%), phospholipids (−18%), GSH (−45%), and inhibited acetylcholinesterase enzyme (–48%). Gangliosides (+ 38%), vitamin C (+ 20%), and calcium (+ 80%) were increased together with an enhancement (+64%) in lipid peroxidation. The combined treatment (vanadium and doxycycline) significantly increased (+25 g) the body weight and relative liver weight of rat was significantly reduced (+5%) compared with vanadium administered group. The levels of metabolic variables were significantly reversed in this group in the following order: cholesterol (+17%), phospholipids (+7%), vitamin C (−14%), acetylcholinesterase enzyme activity (−27%) together with inhibition (−16%) of lipid peroxidation. All levels were (p < 0.05). Doxycycline presented no effect on the levels of GSH, cerebrosides, and gangliosides.

Conclusion Results of this study suggested vanadium-induced oxidation of lipids and sphingolipids in hepatocytes and much of GSH was consumed against high production of reactive oxygen species. Doxycycline protected against vanadium-induced oxidative damage that could be attributed to its free radical scavenging effects on membrane-bound lipids and acetylcholinesterase enzyme.
Cerebrovascular Complications in Pediatric Patients with COVID-19 Infection
Authors: Chaudhry Thymur Ali , Palabiyik Figen , Moum Sarah J.
Published: August 2022

Since the onset of the coronavirus disease 2019 pandemic, a variety of neurological manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been reported in patients, of which one of the most concerning is stroke. This review aims to summarize the current literature and evolving understanding of pediatric cerebrovascular complications in the setting of SARS-CoV-2.
Patient-Specific Factors Associated with Dexmedetomidine Dose Requirements in Critically Ill Children
Authors: Crisamore Karryn R. , Empey Philip E. , Pelletier Jonathan H. , Clark Robert S. B. , Horvat Christopher M.
Published: August 2022

The objective of this study was to evaluate patient-specific factors associated with dexmedetomidine dose requirements during continuous infusion. A retrospective cross-sectional analysis of electronic health record-derived data spanning 10 years for patients admitted with a primary respiratory diagnosis at a quaternary children's hospital and who received a dexmedetomidine continuous infusion (n = 346 patients) was conducted. Penalized regression was used to select demographic, clinical, and medication characteristics associated with a median daily dexmedetomidine dose. Identified characteristics were included in multivariable linear regression models and sensitivity analyses. Critically ill children had a median hourly dexmedetomidine dose of 0.5 mcg/kg/h (range: 0.1–1.8), median daily dose of 6.7 mcg/kg/d (range: 0.9–38.4), and median infusion duration of 1.6 days (range: 0.25–5.0). Of 26 variables tested, 15 were selected in the final model with days of dexmedetomidine infusion (β: 1.9; 95% confidence interval [CI]: 1.6, 2.3), median daily morphine milligram equivalents dosing (mg/kg/d) (β: 0.3; 95% CI: 0.1, 0.5), median daily ketamine dosing (mg/kg/d) (β: 0.2; 95% CI: 0.1, 0.3), male sex (β: −1.1; 95% CI: −2.0, −0.2), and non-Black reported race (β: −1.2; 95% CI: −2.3, −0.08) significantly associated with median daily dexmedetomidine dose. Approximately 56% of dose variability was explained by the model. Readily obtainable information such as demographics, concomitant medications, and duration of infusion accounts for over half the variability in dexmedetomidine dosing. Identified factors, as well as additional environmental and genetic factors, warrant investigation in future studies to inform precision dosing strategies.
Foreign direct investment and the innovation performance of local enterprises
Authors: Yue Wen
Published: August 2022

Based on the micro data set of Chinese manufacturing enterprises, this study examines in detail the impact of foreign direct investment on the innovation performance of Chinese local enterprises and its mechanism. Results show that foreign direct investment helps to improve the innovation performance of Chinese local enterprises, and spillover effect and competition effect are important ways for foreign direct investment to affect the innovation performance of local enterprises. In addition, the impact of foreign direct investment on the innovation of local enterprises of different types varies. Foreign direct investment has significantly promoted the innovation of high-productivity, capital-intensive, non-coastal, export, and non-state-owned enterprises. This study enriches the research literature on foreign direct investment and enterprise innovation and provides new micro evidence for understanding the impact of foreign direct investment on the innovation performance of local enterprises.
Impact of energy poverty on cognitive and mental health among middle-aged and older adults in China
Authors: Li Xuefeng , Yang Han , Jia Jin
Published: August 2022

Energy poverty (EPOV) is considered to have a significant impact on health and has become an essential issue on the policy agenda in most countries, especially those with rapid aging. Cognitive and mental health (CMH) for aging well is just as important a component as physical health, but the literature on the effect of EPOV on CMH is still rare. Using 2014–2018 China Family Panel Studies (CFPS), this study explores EPOV and its impacts on CMH among middle-aged and older adults. Six measures based on energy affordability are constructed to capture the state of EPOV. The results show that the proportion of middle-aged and older adults living in EPOV in China ranges from 24.3% to 27.8%, according to different measures. Applying a two-way FE model, the estimates show that overall, the impact of EPOV on CMH is significantly negative. Furthermore, physical health is an important channel through which EPOV affects CMH. Although EPOV has a significant adverse effect on the CMH of both middle-aged and older adults, it harms the latter more.
Probing the structure of vanadium tetracyanoethylene using electron energy-loss spectroscopy
Authors: Trout Amanda H. , Kurfman Seth W. , Shi Yueguang , Chilcote Michael , Flatté Michael E. , Johnston-Halperin Ezekiel , McComb David W.
Published: August 2022

The molecule-based ferrimagnetic semiconductor vanadium tetracyanoethylene (V[TCNE]x, x ≈ 2) has garnered interest from the quantum information community due to its excellent coherent magnonic properties and ease of on-chip integration. Despite these attractive properties, a detailed understanding of the electronic structure and mechanism for long-range magnetic ordering have remained elusive due to a lack of detailed atomic and electronic structural information. Previous studies via x-ray absorption near edge spectroscopy and the extended x-ray absorption fine structure have led to various proposed structures, and in general, V[TCNE]x is believed to be a three-dimensional network of octahedrally coordinated V2+, each bonded to six TCNE molecules. Here, we elucidate the electronic structure, structural ordering, and degradation pathways of V[TCNE]x films by correlating calculations of density functional theory (DFT) with scanning transmission electron microscopy and electron energy-loss spectroscopy (EELS) of V[TCNE]x films. Low-loss EELS measurements reveal a bandgap and an excited state structure that agree quantitatively with DFT modeling, including an energy splitting between apical and equatorial TCNE ligands within the structure, providing experimental results directly backed by theoretical descriptions of the electronic structure driving the robust magnetic ordering in these films. Core-loss EELS confirms the presence of octahedrally coordinated V+2 atoms. Upon oxidation, changes in the C1s-π* peak indicate that C=C of TCNE is preferentially attacked. Furthermore, we identify a relaxation of the structural ordering as the films age. These results lay the foundation for a more comprehensive and fundamental understanding of magnetic ordering and dynamics in these classes of metal–ligand compounds.
The study of the dynamics of the order parameter of coupled oscillators in the Ott–Antonsen scheme for generic frequency distributions
Authors: Campa Alessandro
Published: August 2022

The Ott–Antonsen ansatz shows that, for certain classes of distribution of the natural frequencies in systems of N globally coupled Kuramoto oscillators, the dynamics of the order parameter, in the limit N→∞, evolves, under suitable initial conditions, in a manifold of low dimension. This is not possible when the frequency distribution, continued in the complex plane, has an essential singularity at infinity; this is the case, for example, of a Gaussian distribution. In this work, we propose a simple approximation scheme that allows one to extend also to this case the representation of the dynamics of the order parameter in a low dimensional manifold. Using the Gaussian frequency distribution as a working example, we compare the dynamical evolution of the order parameter of the system of oscillators, obtained by the numerical integration of the N equations of motion, with the analogous dynamics in the low dimensional manifold obtained with the application of the approximation scheme. The results confirm the validity of the approximation. The method could be employed for general frequency distributions, allowing the determination of the corresponding phase diagram of the oscillator system.
Strain tuning of Néel temperature in YCrO3 epitaxial thin films
Authors: Lee Jin Hong , Marcano Lourdes , Aeschlimann Raphaël , Mawass Mohamad-Assaad , Luo Chen , Gloter Alexandre , Varignon Julien , Radu Florin , Valencia Sergio , Bibes Manuel
Published: August 2022

Epitaxial strain is a useful handle to engineer the physical properties of perovskite oxide materials. Here, we apply it to orthorhombic chromites that are a family of antiferromagnets showing fruitful functionalities as well as strong spin–lattice coupling via antisymmetric exchange interaction along Cr–O–Cr bonds. Using pulsed laser deposition, we grow YCrO3 thin films on various substrates imposing strain levels in the range from −1.8% to +0.3%. The films are stoichiometric with a 3+ valence for Cr both within the films and at their surface. They display an antiferromagnetic spin order below their Néel temperature, which we show can be strongly tuned by epitaxial strain with a slope of −8.54 K/%. A dimensionless figure of merit (defined as the slope normalized by the Néel temperature of bulk) is determined to be 6.1, which is larger than that of other perovskites, such as manganites (5.5), ferrites (2.3), or nickelates (4.6). Density functional theory simulations bring insight into the role of Cr–O bond lengths and oxygen octahedral rotations on the observed behavior. Our results shed light on orthorhombic chromites that may offer an energy-efficient piezo-spintronic operation.
Investigation on anode modes of vacuum arc under different contact opening speeds
Authors: Wang Hongda , Wang Lijun , Zhang Runming , Ma Qiang , Wang Cong , Zhang Zhefeng , Yang Ze , Wang Zhiwei
Published: August 2022

This paper aims to investigate the anode modes of vacuum arc at different opening speeds, especially at a high opening speed that exceeds 3 m/s. The butt contacts made of CuCr30 and CuCr50 with a diameter of 15 mm are used. Experiments are conducted at the current of 3.3, 4.4, 5.5, and 6.3 kA with a frequency of 50 Hz. An electromagnetic repulsion actuator provides the average opening speed from 1.7 to 3 m/s. The experimental results show that the number of droplets splashing into electrodes increases as the arc current increases, while a higher opening speed decreases the droplets. A higher opening speed will reduce the transferred charge before the anode spot type 2, and a higher Cr content increases the transferred charge before the anode spot type 2. Increasing opening speed will decrease the starting time of anode spot type 2, but it increases the gap distance when anode spot type 2 appears. Meanwhile, the increase in Cr content delays the formation of anode spot type 2.
Contrast-enhanced ultrasound tracking of helical propellers with acoustic phase analysis and comparison with color Doppler
Authors: Pane S. , Zhang M. , Iacovacci V. , Zhang L. , Menciassi A.
Published: August 2022

Medical microrobots (MRs) hold the potential to radically transform several interventional procedures. However, to guarantee therapy success when operating in hard-to-reach body districts, a precise and robust imaging strategy is required for monitoring and controlling MRs in real-time. Ultrasound (US) may represent a powerful technology, but MRs' visibility with US needs to be improved, especially when targeting echogenic tissues. In this context, motions of MRs have been exploited to enhance their contrast, e.g., by Doppler imaging. To exploit a more selective contrast-enhancement mechanism, in this study, we analyze in detail the characteristic motions of one of the most widely adopted MR concepts, i.e., the helical propeller, with a particular focus on its interactions with the backscattered US waves. We combine a kinematic analysis of the propeller 3D motion with an US acoustic phase analysis (APA) performed on the raw radio frequency US data in order to improve imaging and tracking in bio-mimicking environments. We validated our US-APA approach in diverse scenarios, aimed at simulating realistic in vivo conditions, and compared the results to those obtained with standard US Doppler. Overall, our technique provided a precise and stable feedback to visualize and track helical propellers in echogenic tissues (chicken breast), tissue-mimicking phantoms with bifurcated lumina, and in the presence of different motion disturbances (e.g., physiological flows and tissue motions), where standard Doppler showed poor performance. Furthermore, the proposed US-APA technique allowed for real-time estimation of MR velocity, where standard Doppler failed.
Perspective on solid-phase epitaxy as a method for searching novel topological phases in pyrochlore iridate thin films
Authors: Kim Woo Jin , Song Jeongkeun , Li Yangyang , Noh Tae Won
Published: August 2022

Pyrochlore iridates exhibit various novel topological phenomena due to their topology and electron correlation. Notably, pyrochlore iridate was the first proposed material system shown to host the time-reversal symmetry broken Weyl semimetal phase. After this profound theoretical proposal, extensive experimental attempts have been made to synthesize high-quality samples in both bulk and film forms. In particular, adjusting thin film geometry represents a practical way to tune the U/t (U: Coulomb interaction and t: for hopping parameter) and identify the various topological phases in the regime U ∼ λ (λ: spin–orbit interaction). However, the instability of pyrochlore iridates at high temperature and low oxygen pressure has long been a barrier to growing pyrochlore iridate thin films by conventional film growth methods. To overcome this, pyrochlore iridate films have often been grown by the solid-phase epitaxy method, which uses a metastable amorphous layer grown at low temperature. During a high temperature post-annealing process, the layer in contact with a single crystalline substrate will crystallize epitaxially in the solid state by rearranging atoms at the interface. Here, we present a perspective on the solid-phase epitaxy as a method to synthesize epitaxial pyrochlore iridate thin films and a way to search for novel correlated phenomena.
Deciphering the structure-photoluminescence correlation at small-tilt-angle grain boundaries in monolayer WS2
Authors: Hou Fuchen , Zhang Yubo , Li Daiyue , Che Liangyu , Lin Junhao
Published: August 2022

Grain boundaries (GBs) frequently emerge in a CVD-grown large-scale transition metal dichalcogenides monolayer thin film, which affect the electronic and optical properties of the material. Photoluminescence (PL) can be easily quenched/enhanced at GBs, which are, however, merely investigated in relatively large tilt angles (θ>14°) in previous research. Here, we experimentally examine the PL properties of monolayer WS2 GBs with tilt angles as small as a few degrees. Contrary to conventional wisdom, we find that PL intensity remains intact by the GBs when their tilt angles θ≤8°. The abnormal PL behavior is elucidated by a detailed structure analysis on the dislocation cores. For a small tilt angle, the strain fields introduced by the defective cores are sparsely distributed without mutual coupling, and the chemical stoichiometry along the GBs preserves very well. These two key structural features of the small-tilt-angle GBs allow excitons to diffuse transparently across the GB, leading to a neglectable influence on the optical and electronic properties, as verified by our first-principle simulations. The PL invariant of the small-tilt-angle GBs sheds light on the future development of CVD-grown wafer-scale techniques and their optical applications.
Observation and analysis of a large banana orbit in the diocotron mode of a coaxial Malmberg–Penning trap
Authors: Eggleston D. L.
Published: August 2022

The diocotron mode of an off-axis electron column is studied in a coaxial version of the Malmberg–Penning trap. Measurements of the diocotron frequency as a function of the bias on the central conductor agree well with a derived theory including finite-length corrections and confinement potential contributions. When the experimental parameters are adjusted to give a very low diocotron frequency, the column motion abruptly changes from an axis-encircling orbit to a large banana-shaped orbit in the r−θ plane with extent Δθ≈270° and Δr/R≈0.25, where R is the wall radius. This banana motion is apparently in response to a previously unknown background construction asymmetry. The size of the asymmetric potential is deduced from orbit data and found to be 45–100 mV. Theoretical modeling shows this to be consistent with a small radial offset δ in the center wire position of δ/R=0.034. Implications and applications of these findings are discussed and a note on obtaining the line density of an electron column in a coaxial trap is given.
A modified Michelson interferometer to measure sub-milliradian changes in angle
Authors: LeDesma C. K. , Ross M. P. , Daly B. E. , Hoyle C. D. , Mola M. M.
Published: August 2022

Modern short-range gravity experiments that seek to test the Newtonian inverse-square law or weak equivalence principle of general relativity typically involve measuring the minute variations in the twist angle of a torsion pendulum. Motivated by various theoretical arguments, recent efforts largely focus on measurements with test mass separations in the sub-millimeter regime. To measure the twist, many experiments employ an optical autocollimator with a noise performance of ∼300 nrad/Hz in the 0.1–10 mHz band, enabling a measurement uncertainty of a few nanoradians in a typical integration time. We investigated an alternative method for measuring a small twist angle through the construction of a modified Michelson interferometer. The main modification is the introduction of two additional arms that allow for improved angular alignment. A series of detectors and LabView software routines were developed to determine the orientation of a mirror attached to a sinusoidally driven rotation stage that oscillated with an amplitude of 0.35 mrad and a period of 200 s. In these measurements, the resolution of the interferometer is 8.1 μrad per fringe, while its dynamic range spanned 0.962 mrad. We compare the performance of this interferometric optical system to existing autocollimator-based methods, discussing its implementation, possible advantages, and future potential, as well as disadvantages and limitations.
De novo mutations in KIF1A-associated neuronal disorder (KAND) dominant-negatively inhibit motor activity and axonal transport of synaptic vesicle precursors
Authors: Anazawa Yuzu , Kita Tomoki , Iguchi Rei , Hayashi Kumiko , Niwa Shinsuke
Published: August 2022

KIF1A is a kinesin superfamily motor protein that transports synaptic vesicle precursors in axons. Cargo binding stimulates the dimerization of KIF1A molecules to induce processive movement along microtubules. Mutations in human
Kif1a
lead to a group of neurodegenerative diseases called KIF1A-associated neuronal disorder (KAND). KAND mutations are mostly de novo and autosomal dominant; however, it is unknown if the function of wild-type KIF1A motors is inhibited by heterodimerization with mutated KIF1A. Here, we have established
Caenorhabditis elegans
models for KAND using CRISPR-Cas9 technology and analyzed the effects of human KIF1A mutation on axonal transport. In our
C. elegans
models, both heterozygotes and homozygotes exhibited reduced axonal transport. Suppressor screening using the disease model identified a mutation that recovers the motor activity of mutated human KIF1A. In addition, we developed in vitro assays to analyze the motility of heterodimeric motors composed of wild-type and mutant KIF1A. We find that mutant KIF1A significantly impaired the motility of heterodimeric motors. Our data provide insight into the molecular mechanism underlying the dominant nature of de novo KAND mutations.
Inhibition of the angiotensin II type 2 receptor AT
2
R is a novel therapeutic strategy for glioblastoma
Authors: Perryman Richard , Renziehausen Alexander , Shaye Hamidreza , Kostagianni Androniki D. , Tsiailanis Antonis D. , Thorne Thomas , Chatziathanasiadou Maria V. , Sivolapenko Gregory B. , El Mubarak Mohamed Ahmed , Han Gye Won , Zarzycka Barbara , Katritch Vsevolod , Lebon Guillaume , Lo Nigro Cristiana , Lattanzio Laura , Morse Sophie V. , Choi James J. , O’Neill Kevin , Kanaki Zoi , Klinakis Apostolos , Crook Tim , Cherezov Vadim , Tzakos Andreas G. , Syed Nelofer
Published: August 2022

Glioblastoma (GBM) is an aggressive malignant primary brain tumor with limited therapeutic options. We show that the angiotensin II (AngII) type 2 receptor (AT
2
R) is a therapeutic target for GBM and that AngII, endogenously produced in GBM cells, promotes proliferation through AT
2
R. We repurposed EMA401, an AT
2
R antagonist originally developed as a peripherally restricted analgesic, for GBM and showed that it inhibits the proliferation of AT
2
R-expressing GBM spheroids and blocks their invasiveness and angiogenic capacity. The crystal structure of AT
2
R bound to EMA401 was determined and revealed the receptor to be in an active-like conformation with helix-VIII blocking G-protein or β-arrestin recruitment. The architecture and interactions of EMA401 in AT
2
R differ drastically from complexes of AT
2
R with other relevant compounds. To enhance central nervous system (CNS) penetration of EMA401, we exploited the crystal structure to design an angiopep-2–tethered EMA401 derivative, A3E. A3E exhibited enhanced CNS penetration, leading to reduced tumor volume, inhibition of proliferation, and increased levels of apoptosis in an orthotopic xenograft model of GBM.
Statistics and topology of fluctuating ribbons
Authors: Yong Ee Hou , Dary Farisan , Giomi Luca , Mahadevan L.
Published: August 2022

Ribbons are a class of slender structures whose length, width, and thickness are widely separated from each other. This scale separation gives a ribbon unusual mechanical properties in athermal macroscopic settings, for example, it can bend without twisting, but cannot twist without bending. Given the ubiquity of ribbon-like biopolymers in biology and chemistry, here we study the statistical mechanics of microscopic inextensible, fluctuating ribbons loaded by forces and torques. We show that these ribbons exhibit a range of topologically and geometrically complex morphologies exemplified by three phases—a twist-dominated helical phase (HT), a writhe-dominated helical phase (HW), and an entangled phase—that arise as the applied torque and force are varied. Furthermore, the transition from HW to HT phases is characterized by the spontaneous breaking of parity symmetry and the disappearance of perversions (that correspond to chirality-reversing localized defects). This leads to a universal response curve of a topological quantity, the link, as a function of the applied torque that is similar to magnetization curves in second-order phase transitions.
A neural network solves, explains, and generates university math problems by program synthesis and few-shot learning at human level
Authors: Drori Iddo , Zhang Sarah , Shuttleworth Reece , Tang Leonard , Lu Albert , Ke Elizabeth , Liu Kevin , Chen Linda , Tran Sunny , Cheng Newman , Wang Roman , Singh Nikhil , Patti Taylor L. , Lynch Jayson , Shporer Avi , Verma Nakul , Wu Eugene , Strang Gilbert
Published: August 2022

We demonstrate that a neural network pretrained on text and fine-tuned on code solves mathematics course problems, explains solutions, and generates questions at a human level. We automatically synthesize programs using few-shot learning and OpenAI’s Codex transformer and execute them to solve course problems at 81% automatic accuracy. We curate a dataset of questions from Massachusetts Institute of Technology (MIT)’s largest mathematics courses (Single Variable and Multivariable Calculus, Differential Equations, Introduction to Probability and Statistics, Linear Algebra, and Mathematics for Computer Science) and Columbia University’s Computational Linear Algebra. We solve questions from a MATH dataset (on Prealgebra, Algebra, Counting and Probability, Intermediate Algebra, Number Theory, and Precalculus), the latest benchmark of advanced mathematics problems designed to assess mathematical reasoning. We randomly sample questions and generate solutions with multiple modalities, including numbers, equations, and plots. The latest GPT-3 language model pretrained on text automatically solves only 18.8% of these university questions using zero-shot learning and 30.8% using few-shot learning and the most recent chain of thought prompting. In contrast, program synthesis with few-shot learning using Codex fine-tuned on code generates programs that automatically solve 81% of these questions. Our approach improves the previous state-of-the-art automatic solution accuracy on the benchmark topics from 8.8 to 81.1%. We perform a survey to evaluate the quality and difficulty of generated questions. This work automatically solves university-level mathematics course questions at a human level and explains and generates university-level mathematics course questions at scale, a milestone for higher education.
Utilization of diverse organophosphorus pollutants by marine bacteria
Authors: Despotović Dragana , Aharon Einav , Trofimyuk Olena , Dubovetskyi Artem , Cherukuri Kesava Phaneendra , Ashani Yacov , Eliason Or , Sperfeld Martin , Leader Haim , Castelli Andrea , Fumagalli Laura , Savidor Alon , Levin Yishai , Longo Liam M. , Segev Einat , Tawfik Dan S.
Published: August 2022

Anthropogenic organophosphorus compounds (AOPCs), such as phosphotriesters, are used extensively as plasticizers, flame retardants, nerve agents, and pesticides. To date, only a handful of soil bacteria bearing a phosphotriesterase (PTE), the key enzyme in the AOPC degradation pathway, have been identified. Therefore, the extent to which bacteria are capable of utilizing AOPCs as a phosphorus source, and how widespread this adaptation may be, remains unclear. Marine environments with phosphorus limitation and increasing levels of pollution by AOPCs may drive the emergence of PTE activity. Here, we report the utilization of diverse AOPCs by four model marine bacteria and 17 bacterial isolates from the Mediterranean Sea and the Red Sea. To unravel the details of AOPC utilization, two PTEs from marine bacteria were isolated and characterized, with one of the enzymes belonging to a protein family that, to our knowledge, has never before been associated with PTE activity. When expressed in
Escherichia coli
with a phosphodiesterase, a PTE isolated from a marine bacterium enabled growth on a pesticide analog as the sole phosphorus source. Utilization of AOPCs may provide bacteria a source of phosphorus in depleted environments and offers a prospect for the bioremediation of a pervasive class of anthropogenic pollutants.
Indirect translation of foreign films for cinematic release in China
Authors: Jin Haina , Zhang Yichi , He Xiaomin
Published: August 2022

Scholars have acknowledged the widespread use of indirect translation in audiovisual translation. Some researchers have made use of text analysis to explore the effects of indirect translation on voiceover and subtitling. However, a bigger picture of indirect translation in the audiovisual translation landscape is yet to be painted. We create a database of 242 foreign films, which contains all the imported films for cinematic release in China in 2018 and 2019, and do a quantitative and qualitative analysis to present an overview of indirect translation of foreign films for cinematic release in China. Professionals from film translation studios in China are interviewed to reveal the indirect translation process. Furthermore, we use Prooi ‘Prey’ (Maas 2016), a Dutch horror film directed by Dick Maas, and its Chinese subtitled version as a case study to investigate the implications of indirect translation on the ultimate target text in the Chinese context.
Microstructure and mechanical properties of a double-pass friction stir processed AZ31B magnesium alloy
Authors: Nan Xu , Bo-Kun Gu , Yue Fan , Jun Shen , Qi-Ning Song , Jian-Hua Zhao , Ye-Feng Bao
Published: August 2022

Double-pass friction stir processing (2P-FSP) was performed on a 6-mm thick AZ31B magnesium alloy plate. Compared to single-pass FSP, the 2P-FSP led to more severe thermal deformation, causing the average grain size in the stir zone to increase, but the dynamic recrystallisation process was more complete. Tensile test results revealed that the yield strength of the 2P-FSP stir zone was improved. Schmid factor analysis showed that the basal slip of 2P-FSP was more difficult to activate. The extension twins formed during the tensile process interacted with the original dislocations, resulting in a better match of strength and ductility. In addition, the physical and mathematical models were established based on the dynamic recrystallisation mechanisms and mechanical property enhancement mechanisms.
Listening effort in individuals with noise-induced hearing loss
Authors: Shetty Hemanth Narayan , Raju Suma , Kumar Yashwanth , Singh Sanjana S.
Published: August 2022

Objective

The cognitive capacity allocates the resources effectively for effortless listening to speech presented in noise. This entity is minimally explored in individuals with noise-induced hearing loss (NIHL); therefore, the listening effort in individuals with NIHL at different signal-to-noise ratios was investigated.

Method

Forty participants with symmetrical mild sensorineural hearing loss were sub-grouped into control and clinical groups. The listening effort was measured using the dual-task paradigm at four different signal-to-noise conditions. In addition, a gap detection test was used to assess temporal processing ability.

Results

The repeat and recall scores were reduced with decreased signal-to-noise ratios in each group. These differences were significantly poorer in the clinical group than in the control group. A significant strong positive relation was observed between the recall and repeat scores of both groups for the listening effort tasks. Temporal processing impairment was significantly higher in the clinical group than in the control group.

Conclusion

Individuals with noise-induced hearing loss exhibit a significant temporal processing impairment that leads to effortful listening than hearing loss alone.
Deep band modulation, frequency discrimination, temporal resolution and audibility effects
Authors: Shetty Hemanth Narayan , Raju Suma
Published: August 2022

Objective

The temporal envelope enhancement using deep band modulation (DBM) exaggerates the temporal peaks and valleys in the speech signal, thereby reducing the difficulty in the perception of speech in noise.

Method

Ten participants in each group of older adults with and without hearing loss in 65 to 83 years were recruited. A repeated measures research design was utilised to investigate phrase perception in unprocessed and deep band modulated phrases at different signal-to-noise (SNR) ratios (−4, 0, and +4). Temporal processing, spectral discrimination and speech intelligibility index were assessed.

Results

Regardless of the group, the phrase perception in the deep band modulated condition was significantly better than the unprocessed condition at each SNR. A significantly strong negative correlation was observed between: Gap detection threshold (GDT) and phrase perception scores in unprocessed condition at −4 dB SNR in each group; frequency difference limen in each condition and DBM phrase perception at −4 dB SNR in the older adult group with hearing impaired (OAG-HI) group. Furthermore, audibility reflected in the speech intelligibility index (SII) did not influence phrase recognition irrespective of condition, SNRs and group.

Conclusion

Increased modulation depth enables the participants to use the available temporal envelope, especially at the portion of the phrase where noise is less energetically masked.
On generally covariant mathematical formulation of Feynman integral in Lorentz signature
Authors: László András
Published: August 2022

It is widely accepted that the Feynman integral is one of the most promising methodologies for defining a generally covariant formulation of nonperturbative interacting quantum field theories (QFTs) without a fixed prearranged causal background. Recent literature suggests that if the spacetime metric is not fixed, e.g. because it is to be quantized along with the other fields, one may not be able to avoid considering the Feynman integral in the original Lorentz signature, without Wick rotation. Several mathematical phenomena are known, however, which are at some point showstoppers to a mathematically sound definition of Feynman integral in Lorentz signature. The Feynman integral formulation, however, is known to have a differential reformulation, called to be the master Dyson–Schwinger (MDS) equation for the field correlators. In this paper it is shown that a particular presentation of the MDS equation can be cast into a mathematically rigorously defined form: the involved function spaces and operators can be strictly defined and their properties can be established. Therefore, MDS equation can serve as a substitute for the Feynman integral, in a mathematically sound formulation of constructive QFT, in arbitrary signature, without a fixed background causal structure. It is also shown that even in such a generally covariant setting, there is a canonical way to define the Wilsonian regularization of the MDS equation. The main result of the paper is a necessary and sufficient condition for the regularized MDS solution space to be nonempty, for conformally invariant Lagrangians. This theorem also provides an iterative approximation algorithm for obtaining regularized MDS solutions, and is guaranteed to be convergent whenever the solution space is nonempty. The algorithm could eventually serve as a method for putting Lorentz signature QFTs onto lattice, in the original metric signature.
Programmable intelligent liquid matter: material, science and technology
Authors: Zhou Yingxin , Zu Jiasheng , Liu Jing
Published: August 2022

Intelligent responses, transformation and desired delivery of liquids involve the intersection among materials, physics, and chemistry. The precise programmed operation has been found rather significant in many emerging fields, such as microfluidic devices, digital fluids, intelligent matter, responsive liquid machines, interactive display, soft robotic system and drug delivery, etc. This article is dedicated to presenting a comprehensive review of recent advances in the programmable actuation of liquid matter controlled by unique substrate structures and various physical fields. First, the fundamental theories of asymmetric surface microstructure and specifically administrated external effects such as electric, magnetic, acoustic, light, and thermal fields to drive droplets are illustrated. Then, we compare the advantages and disadvantages of these typical technological strategies. Furthermore, the practical multifunctional extension of programmable liquids based on different actuation mechanisms is presented. Finally, we summarize the design schemes of programming units for liquid matter and give perspective on possible future research directions, providing a brief reference for researchers interested in the field.
Ellipticity dependence of high-order harmonic generation in disordered semiconductors
Authors: Orlando Gianfranco , Lee Min-I , Ho Tak-San
Published: August 2022

We analyze the ellipticity dependence of high order harmonic generation (HHG) in disordered semiconductors. We show that a disordered crystal can radiated HHG spectra containing only odd harmonics of the laser frequency for all values of the ellipticity of the laser. Furthermore, we show that the HHG yield of our disordered models decreases monotonically with increasing laser ellipticity as observed in recent experiments. I particular, our numerical calculations, based on a coarse grained model, reproduce many of the qualitative features of the experimental HHG spectra of ZnO and GaAs.
A thermally erasable silicon oxide layer for molecular beam epitaxy
Authors: Hou Yaonan , Jia Hui , Tang Mingchu , Mosberg Aleksander Buseth , Ramasse Quentin M , Skandalos Ilias , Noori Yasir , Yang Junjie , Liu Huiyun , Seeds Alwyn , Gardes Frederic
Published: August 2022

We present a systematic study of the oxidation and deoxidation behaviours of several kinds of ultrathin silicon oxide layers frequently used in silicon (Si) technology, which in this work serve as surface protecting layers for molecular beam epitaxy (MBE). With various characterization techniques, we demonstrate that a chemically grown silicon oxide layer is the most promising candidate for subsequent removal in an ultra-high vacuum chamber at a temperature of 1000 ∘C, without making use of a reducing agent. As a demonstration, a tensile-strained Ge(100) layer is epitaxially grown on the deoxidised wafer with an atomically flat surface and a low threading dislocation density of 3.33 × 108 cm−2. Our findings reveal that the ultra-thin oxide layer grown using a chemical approach is able to protect Si surfaces for subsequent MBE growth of Ge. This approach is promising for the growth of III/V-on-Si (using Ge as a buffer) and all group-IV related epitaxy for integration on the Si photonics platforms.
Spatial attention-based convolutional transformer for bearing remaining useful life prediction
Authors: Chen Chong , Wang Tao , Liu Ying , Cheng Lianglun , Qin Jian
Published: August 2022

The remaining useful life (RUL) prediction is of significance to the health management of bearings. Recently, deep learning has been widely investigated for bearing RUL prediction due to its great success in sequence learning. However, the improvement of the prediction accuracy of existing deep learning algorithms heavily relies on feature engineering such as handcrafted feature generation and time–frequency transformation, which increase the complexity and difficulty of the actual deployment. In this paper, a novel spatial attention-based convolutional transformer (SAConvFormer) is proposed to establish an accurate bearing RUL prediction model based on raw vibration data without prior knowledge or feature engineering. In this algorithm, firstly, a convolutional neural network enhanced by a spatial attention mechanism is proposed to squeeze the feature maps and extract the local and global features from raw bearing vibration data effectively. Then, the extracted senior features are fed into a transformer network to further explore the sequential patterns relevant to the bearing RUL. An experimental study using the XJTU-SY rolling bearings dataset revealed the merits of the proposed deep learning algorithm in terms of root-mean-square-error (RMSE) and mean-absolute-error (MAE) in comparison with other state-of-the-art algorithms.
Atomic level simulations of the phase stability and stacking fault energy of FeCoCrMnSi high entropy alloy
Authors: Salloom Riyadh , Baskes Michael I , Srinivasan Srivilliputhur G
Published: August 2022

High entropy alloys (HEAs) have many promising properties beneficial to advanced technologies. However, their underlying deformation mechanisms are largely unclear. So, as a first step, we have developed a modified embedded atom method potential for FeCoCrMnSi alloys to study such mechanisms. We predict the phase stability, chemical short-range ordering (CSRO), and stacking fault energy (SFE) of a specific alloy system using molecular dynamics (MD) and hybrid Monte-Carlo and molecular dynamics (MC/MD) simulation techniques. Room temperature MD simulations showed that both the potential energy and free energy of the single phase ε-hcp alloy is marginally more stable than the γ-fcc phase alloy, which resulted in a large, negative SFE. However, the room temperature MC/MD simulation showed an opposite trend where the γ-fcc phase was found to be more stable than the ε-hcp phase, and this resulted in a small, positive SFE. The prediction of the lower energy γ-fcc phase and resultant SFE agreed well with the experimentally reported SFE and phase stability for the Fe40Co20Cr15Mn20Si5 HEA, illustrating the importance of CSRO. Also, the calculated basal SFE of the hcp phase was close to that of the fcc phase. Therefore, the MC/MD implementation is crucial for the proper prediction of the phase stability and structural evolution in this HEA system. Many previous studies showed the ability of hybrid MC/MD technique to obtain consistent structural and configurational information of different alloy systems. The current work illustrates the potential of accelerating HEA materials development by utilizing computational methods based on the MC/MD technique which can reduce time and cost associated with experimental methods.
Precisely controlled polydopamine-mediated antibacterial system: mathematical model of polymerization, prediction of antibacterial capacity, and promotion of wound healing
Authors: Zeng Yun , Yi Tong , Ma Jingwen , Han Ming , Xu Xinyi , Dan Chen  , Chen Xueli , Wang Risheng , Zhan Yonghua
Published: August 2022

In this work, the polydopamine (PDA)-mediated antibacterial system is synthesized for in vitro and in vivo antimicrobial activities. To precisely control the surface modification of nanodiamonds (NDs), a mathematical kinetics model of PDA deposition is established, and the conditions of synthesis reaction are discussed including the concentrations of dopamine, the reaction time, and the kinetic constant k
1, which is a function of several variables associated with the reaction temperature, light irradiance, pH value and concentration of dissolved O2 in the solution. A simulation reveals that the deposition of PDA is positively correlated with these factors and will be terminated if dissolved O2 levels are inadequate. Then, the precisely controlled thickness of PDA layers can regulate the formation of AgNPs, resulting in a rise in the intensity of Raman peaks and a predicted antibacterial activity against E. coli in vitro. An optimized antibacterial hydrogel incorporating NDs-PDA/Ag is prepared and characterized by the Fourier transform infrared spectroscopy and field emission scanning electron microscopy. Finally, the antibacterial tests are performed to promote in vivo wound healing, as confirmed by pathological and immunohistochemical-stained tissue sections. This work provides a theoretical foundation for predicting the PDA-assisted surface modification of NDs, resulting in a divinable antibacterial effect and promoting in vivo wound healing.