bluuebunny/crossref_metadata_2025 huggingface dataset:
Failure in Cervical Spinal Fusion and Current Management Modalities
Authors: Verla Terence , Xu David S. , Davis Matthew J. , Reece Edward M. , Kelly Michelle , Nunez Mervin , Winocour Sebastian J. , Ropper Alexander E.
Published: May 2021

Failed fusion in the cervical spine is a multifactorial problem stemming from a combination of patient and surgical factors. Patient-related risk factors such as steroid use, poor bone quality, and smoking can be optimized preoperatively. Age, prior radiation, prior surgery, and underlying genetics are nonmodifiable patient-centered risk factors. Surgical risks for failed fusion include the number of segments fused, anterior versus posterior approach for fusion, the type of bone graft, and the instrumentation utilized. Many symptomatic cases of failed fusion (pseudarthrosis) result in pain, neurological deficits, or loosened hardware necessitating a revision surgery consisting of extending the prior construct and utilizing additional allografts or autografts to augment the fusion. Given the relatively mobile nature of the cervical spine, pseudoarthrosis (either known or anticipated) must be recognized by the spine surgeon, and steps should be considered to optimize the likelihood of future fusion. This consists of both performing a rigid fixation and using appropriate bone graft to enhance the environment for arthrodesis. Vascularized bone grafts are a useful tool to augment fusion and provide added structural stability in cases at high risk of pseudoarthrosis.
Community-Onset Venous Thromboembolism in Children: Pediatric Emergency Medicine Perspectives
Authors: Betensky Marisol , White Melissa , Lawson Simone L. , Goldenberg Neil A.
Published: May 2021

Pediatric venous thromboembolism (VTE) is a condition increasingly encountered by emergency medicine physicians. Unfortunately, despite increased incidence, the diagnosis of pediatric VTE relies on a high index of suspicion from clinicians. Delays in diagnosis and initiation of treatment can lead to poor outcomes in children, including an increased risk of mortality from pulmonary embolism, increased risk of VTE recurrence, and the development of the post-thrombotic syndrome. The majority of pediatric VTE events are associated with the presence of at least one underlying prothrombotic risk. Timely recognition of these risk factors in the emergency department (ED) setting is paramount for a prompt diagnosis and treatment initiation. Compared with children with hospital-acquired VTE, children presenting to the ED with new onset VTE tend to be older (>11 years of age), have a lower incidence of co-morbidities, and present more frequently with a deep venous thrombosis of the lower extremity. Currently, there are no validated pediatric-specific VTE clinical pretest probability tools that reliably assist with the accurate and timely diagnosis of pediatric VTE. Compression ultrasound with Doppler is the most common imaging modality used for VTE diagnosis, and low molecular weight heparins are the most common anticoagulants initiated in children presenting with VTE in the ED. Special consideration should be given to patients who present to the ED already on anticoagulation therapy who may require acute management for clinically-significant bleeding or change in antithrombotic therapy approach for progression/recurrence of VTE.
Failure in Lumbar Spinal Fusion and Current Management Modalities
Authors: Cruz Alex , Ropper Alexander E. , Xu David S. , Bohl Michael , Reece Edward M. , Winocour Sebastian J. , Buchanan Edward , Kaung Geoffrey
Published: May 2021

Lumbar spinal fusion is a commonly performed procedure to stabilize the spine, and the frequency with which this operation is performed is increasing. Multiple factors are involved in achieving successful arthrodesis. Systemic factors include patient medical comorbidities—such as rheumatoid arthritis and osteoporosis—and smoking status. Surgical site factors include choice of bone graft material, number of fusion levels, location of fusion bed, adequate preparation of fusion site, and biomechanical properties of the fusion construct. Rates of successful fusion can vary from 65 to 100%, depending on the aforementioned factors. Diagnosis of pseudoarthrosis is confirmed by imaging studies, often a combination of static and dynamic radiographs and computed tomography. Once pseudoarthrosis is identified, patient factors should be optimized whenever possible and a surgical plan implemented to provide the best chance of successful revision arthrodesis with the least amount of surgical risk.
Sepsis and Mortality Prediction in Very Low Birth Weight Infants: Analysis of HeRO and nSOFA
Authors: Zeigler Angela C. , Ainsworth John E. , Fairchild Karen D. , Wynn James L. , Sullivan Brynne A.
Published: May 2021

Objective Scores to predict sepsis or define sepsis severity could improve care for very low birth weight (VLBW) infants. The heart rate characteristics (HRC) index (HeRO score) was developed as an early warning system for late-onset sepsis (LOS), and also rises before necrotizing enterocolitis (NEC). The neonatal sequential organ failure assessment (nSOFA) was developed to predict sepsis-associated mortality using respiratory, hemodynamic, and hematologic data. The aim of this study was to analyze the HRC index and nSOFA near blood cultures in VLBW infants relative to diagnosis and sepsis-associated mortality.

Study Design Retrospective, single-center study of VLBW infants from 2011 to 2019. We analyzed HRC index and nSOFA around blood cultures diagnosed as LOS/NEC. In a subgroup of the cohort, we analyzed HRC and nSOFA near the first sepsis-like illness (SLI) or sepsis ruled-out (SRO) compared with LOS/NEC. We compared scores by diagnosis and mortality during treatment.

Results We analyzed 179 LOS/NEC, 93 SLI, and 96 SRO blood culture events. In LOS/NEC, the HRC index increased before the blood culture, while nSOFA increased at the time of culture. Both scores were higher in nonsurvivors compared with survivors and in LOS/NEC compared with SRO. The nSOFA 12 hours after the time of blood culture predicted mortality during treatment better than any other time point analyzed (area under the curve 0.91).

Conclusion The HRC index provides earlier warning of imminent sepsis, whereas nSOFA after blood culture provides better prediction of mortality.

Key Points
Profile of Patients with Isolated Distal Deep Vein Thrombosis versus Proximal Deep Vein Thrombosis or Pulmonary Embolism: RE-COVERY DVT/PE Study
Authors: Schellong Sebastian , Ageno Walter , Casella Ivan B. , Chee Kok Han , Schulman Sam , Singer Daniel E. , Desch Marc , Tang Wenbo , Voccia Isabelle , Zint Kristina , Goldhaber Samuel Z.
Published: May 2021

Isolated distal deep vein thrombosis (IDDVT) is presumed to be more benign than proximal DVT (PDVT) or pulmonary embolism (PE), suggesting a need for different management approaches. This subgroup analysis of the RE-COVERY DVT/PE global, observational study investigated patient characteristics, hospitalization details, and anticoagulant therapy in patients with IDDVT in real-world settings in 34 countries enrolled from January 2016 to May 2017. Data were analyzed descriptively according to the type and location of the index venous thromboembolism (VTE): IDDVT, PDVT ± distal DVT (DDVT), and PE ± DVT. Of the 6,095 eligible patients, 323 with DVT located outside the lower limb and no PE were excluded. Of the remaining 5,772 patients, 17.6% had IDDVT, 39.9% had PDVT ± DDVT, and 42.5% had PE ± DVT. IDDVT patients were younger and had fewer risk factors for VTE than the other groups. Other comorbidities were less frequent in the IDDVT group, except for varicose veins, superficial thrombophlebitis, and venous insufficiency. IDDVT patients were less likely to be diagnosed in an emergency department (22.3 vs. 29.7% for PDVT ± DDVT and 45.4% for PE ± DVT) or hospitalized for VTE (29.2 vs. 48.5% for PDVT ± DDVT and 75.0% for PE ± DVT). At hospital discharge or 14 days after diagnosis (whichever was later), non–vitamin K antagonist oral anticoagulants were the most commonly used anticoagulants (55.6% for IDDVT, 54.7% for PDVT ± DDVT, and 52.8% for PE ± DVT). Although differences in patient characteristics, risk factors, and clinical management were identified, anticoagulant treatment of IDDVT was almost equal to that of PDVT or PE. Prospective studies should investigate whether, in a global perspective, this is an appropriate use of anticoagulants.
Housing coalition dynamics: a comparative perspective
Authors: Lima Valesca
Published: May 2021

Social movement coalitions are a vital component within the dynamics of political mobilization. While previous research has established why and how coalitions emerge and dissolve, how they are maintained and the outcomes they generate have been less explored, especially in housing studies. This research contributes to the study of movement coalitions through an empirical examination of the dynamics of how coalitions interact, cooperate, and sustain alliances, in addition to exploring the outcomes that are produced as a result of these coalitions. It draws upon a comparative approach of housing coalitions in Dublin and Lisbon, where local housing groups have played a critical role in protesting against housing injustices and in articulating alternative policy solutions to the housing crisis. In mapping the diversity of coalition members, this research finds that tolerance for difference and negotiation capacity impacts how long coalitions last as well as the outcomes that they lead to. This study contributes to the study of coalitions by analyzing the relationship between outcomes and the mechanisms which sustain coalitions using a comparative framework.
Enhancing neuromorphic computing using memristors
Authors: Frank Jodi Ackerman
Published: May 2021

Physical properties of these resistive memory devices could contribute to energy efficient brain-like circuit systems.
UV light exposure can enhance the field emission performance of nano vacuum devices
Authors: Yiu Yuen
Published: May 2021

The field electron emission performance of a silicon gated field emission array improved by a factor of 10 after a 70-minute exposure to UV light.
Transient response of the time-delay system excited by Gaussian noise based on complex fractional moments
Authors: Niu Lizhi , Xu Wei , Guo Qin
Published: May 2021

In this paper, the transient response of the time-delay system under additive and multiplicative Gaussian white noise is investigated. Based on the approximate transformation method, we convert the time-delay system into an equivalent system without time delay. The one-dimensional Ito stochastic differential equation with respect to the amplitude response is derived by the stochastic averaging method, and Mellin transformation is utilized to transform the related Fokker–Planck–Kolmogorov equation in the real numbers field into a first-order ordinary differential equation (ODE) of complex fractional moments (CFM) in the complex number field. By solving the ODE of CFM, the transient probability density function can be constructed. Numerical methods are used to ascertain the effectiveness of the CFM method, the effects of system parameters on system response and the level of error vary with time as well as noise intensity are investigated. In addition, the CFM method is first implemented to analyze transient bifurcation, and the relation between CFM and bifurcation is discussed for the first time. Furthermore, the imperfect symmetry property appear on the projection map of joint probability density function.
Betatron coupling measurement and optimization in Indus-2 storage ring
Authors: Husain Riyasat , Prakash Suraj , Ghodke A. D.
Published: May 2021

Brightness is an important parameter for any synchrotron radiation source. Correcting the emittance coupling is one of the ways to increase photon beam brightness in the operational storage ring. The main source of this effect is betatron coupling, resulting from the skew quadrupolar errors. Tune split and Linear Optics from Closed Orbit (LOCO) techniques are used to measure the betatron coupling. We discuss the measurement result of betatron coupling and its correction in the Indus-2 storage ring using available four power supplies, as the knobs, driving the skew quadrupole windings located on sextupoles. The measured coupling ratio of ∼0.8% closely matches with the coupling ratio obtained from the LOCO fit model. Based on LOCO correction, the coupling ratio can be reduced to ∼0.4%, which is limited by the degrees of freedom and not by the field strengths. To achieve a smaller and controlled value of coupling, simulation studies based on the LOCO fit model and using the multi-objective differential evolution algorithm with more skew quadrupole power supplies are performed in Indus-2. With sixteen independent power supplies, the emittance ratio can be reduced to <0.04% and the brightness enhances by an order of magnitude. Besides, the optimization method used provides quantitative trade-offs between coupling related parameters such as beam tilt angle, emittance ratio, vertical emittance, and vertical beam size, and desired values can be chosen from the Pareto optimal front.
The multi-optics high-resolution absorption x-ray spectrometer (HiRAXS) for studies of materials under extreme conditions
Authors: Stoupin S. , Thorn D. B. , Ose N. , Gao L. , Hill K. W. , Ping Y. , Coppari F. , Kozioziemski B. , Krygier A. , Sio H. , Ayers J. , Bitter M. , Kraus B. , Efthimion P. C. , Schneider M. B.
Published: May 2021

We report the development of a high-resolution spectrometer for extended x-ray absorption fine structure (EXAFS) studies of materials under extreme conditions. A curved crystal and detector in the spectrometer are replaceable such that a single body is employed to perform EXAFS measurements at different x-ray energy intervals of interest. Two configurations have been implemented using toroidal crystals with Ge 311 reflection set to provide EXAFS at the Cu K-edge (energy range 8.9–9.8 keV) and Ge 400 reflection set to provide EXAFS at the Ta L3-edge (9.8–10.7 keV). Key performance characteristics of the spectrometer were found to be consistent with design parameters. The data generated at the National Ignition Facility have shown an ≃3 eV spectral resolution for the Cu K-edge configuration and ≃6 eV for the Ta L3-edge configuration.
Regularization of least squares problems in CHARMM parameter optimization by truncated singular value decompositions
Authors: Urwin Derek J. , Alexandrova Anastassia N.
Published: May 2021

We examine the use of the truncated singular value decomposition and Tikhonov regularization in standard form to address ill-posed least squares problems Ax = b that frequently arise in molecular mechanics force field parameter optimization. We illustrate these approaches by applying them to dihedral parameter optimization of genotoxic polycyclic aromatic hydrocarbon-DNA adducts that are of interest in the study of chemical carcinogenesis. Utilizing the discrete Picard condition and/or a well-defined gap in the singular value spectrum when A has a well-determined numerical rank, we are able to systematically determine truncation and in turn regularization parameters that are correspondingly used to produce truncated and regularized solutions to the ill-posed least squares problem at hand. These solutions in turn result in optimized force field dihedral terms that accurately parameterize the torsional energy landscape. As the solutions produced by this approach are unique, it has the advantage of avoiding the multiple iterations and guess and check work often required to optimize molecular mechanics force field parameters.
Photoluminescence from an emitter layer sandwiched between the stack of metasurfaces
Authors: Murai Shunsuke , Agata Kenichi , Tanaka Katsuhisa
Published: May 2021

The combination of metasurface with optical emitters provides a unique opportunity to control the emission. The metasurface effect strongly depends on the spectral overlap between the internal electronic transitions of the emitter and the optical resonances of the metasurface. Elaborate design of the metasurface could realize the resonances at both absorption and emission wavelengths of the emitter, but it usually leads to complexity in fabrication. In this work, we propose a very simple strategy to obtain the resonances at both wavelengths by sandwiching the emitter layer with a pair of metasurfaces designed for absorption and emission, respectively. For this purpose, we use a sticker of Al metasurface, which is the array of Al nanoparticles embedded in a flexible polymer film that can be stuck on any clean surfaces. The metasurface stack is prepared by simply placing the sticker, resonating at the emission wavelength, on the emitter layer deposited on the TiO2 metasurface resonating at the absorption wavelength. The overall enhancement achieved for the stack of the metasurfaces can be understood roughly as the multiplication of contributions from the respective metasurfaces. Employing a sticker provides an easy-to-make way of constructing a stack of metasurfaces, which increases the degree of freedom in designing the metasurface-coupled emitters.
Coexisting morphotropic phase boundary and giant strain gradient in BiFeO3 films
Authors: Tang Y. L. , Zhu Y. L. , Zou M. J. , Wang Y. J. , Ma X. L.
Published: May 2021

Large compressive strains may introduce giant tetragonality and morphotropic phase boundaries in perovskite BiFeO3 films, where the coexisting tetragonal and rhombohedral phases (T like and R like phases) are identified to exhibit large piezoelectric response. Here, we have further achieved mechanical bending deformations in R like BiFeO3 through its neighboring T like BiFeO3 phases, where a strain gradient of ∼106/m was identified. Aberration-corrected scanning transmission electron microscopy revealed not only the strain distributions but also the atomic scale Fe polar displacement in the gradient R like BiFeO3. In spite of the giant strain gradient, the polarization direction in each R like BiFeO3 unit cell was found mainly along its diagonal direction, suggesting that potential flexoelectric coupling induced polarization in BiFeO3 is smaller than its spontaneous polarizations, while a large built-in electric field can be obtained via the large strain gradient. Our results indicate that the common phase coexistences in oxide materials could be further manipulated to introduce elastic strain gradients and tune the properties for oxide films.
Alloying Cr2/3Te in AgCrSe2 compound for improving thermoelectrics
Authors: Tang Mingjing , Li Juan , Wang Yadong , Gong Houjun , Huang Yanping , Kang Bin , Zhang Kun , Ang Ran
Published: May 2021

AgCrSe2, which crystallizes in alternative layers of Ag+ and CrSe2− octahedral structure, has shown great potential as good thermoelectric material due to its unique ultralow lattice thermal conductivity. In this work, compound Cr2/3Te is alloyed with the matrix Ag0.97CrSe2 and the carrier concentration ranges within 1018–1020 cm−3, enabling a reliable assessment of transport properties based on single parabolic band model at room temperature. Moreover, homogeneous nanoprecipitate is observed in the matrix for high Cr2/3Te content samples, which leads to the scattering of main heat carrier of long-wavelength phonons, and thus a slight reduction of lattice thermal conductivity (∼0.3 W/m K) compared with intrinsic AgCrSe2. Combined with the optimized carrier concentration and the low lattice thermal conductivity, a figure of merit zT of 0.6 at 650 K is achieved, exceeding other reported AgCrSe2 systems, demonstrating the current Ag0.97CrSe2(Cr2/3Te)x materials as good potential thermoelectrics.
Light-induced pressure anisotropy and temperature change in atomic gases
Authors: Chermyaninov I. V. , Chernyak V. G.
Published: May 2021

Pressure anisotropy and radiative temperature change are investigated in a one-component atomic gas in the field of resonant laser radiation. This is a continuation of the work in Chermyaninov and Chernyak [“Light-induced phenomena in one-component gas: Pressure anisotropy and change of gas temperature,” Phys. Fluids 32, 017105 (2020)]. An atomic gas located between infinite parallel plates is considered. A traveling electromagnetic wave propagates along the plates, whose frequency is close to that of electron transitions in gas atoms from a ground state to an excited one. Resonant optical radiation stimulates gas pressure anisotropy and a change in its temperature. General expressions are obtained for the longitudinal and transverse changes in gas pressure, as well as for the optical change in its temperature. The kinetic coefficients that determine the magnitude of these phenomena are calculated for large Knudsen numbers (Kn). The results for atomic and molecular gases are compared.
Tuning magnetic anisotropy by continuous composition-gradients in a transition metal oxide
Authors: Kan Daisuke , Suzuki Ikumi , Shimakawa Yuichi
Published: May 2021

Compositional tuning of correlations between electrons, spins, and lattices in solids is a key strategy for exploring quantum phenomena. In contrast to uniform chemical substitutions that are widely used for the compositional tunings, continuous variations in compositions along a given direction of materials (composition gradients) are expected to modulate translational crystal symmetries and electronic band structures, leading to unique properties not seen in homogeneously substituted materials. Preparing compositionally graded materials, however, is still challenging as it requires elaborate fabrication processes, and how composition gradients affect materials’ properties remains elusive. Here, we show that composition gradients can be made by simply depositing films under continuously varying oxygen pressures by pulsed laser deposition. Applying this technique to the inverse-spinel-structured ferrimagnet NiCo2O4, we found that composition gradients in NiCo2O4 epitaxial films tune the magnetic anisotropy and stabilize the magnetizations modulated along the gradient, which are not seen in compositionally uniform films. The spatially modulated magnetization can also be reversed in controlled manners through distinct antiferromagnetically coupled magnetization configurations in the single material. Our results demonstrate the potential of composition gradients to tune materials’ properties and explore a new class of materials with added functionalities.
Edge effect on flexoelectronic properties of Janus MoSSe nanoribbons: A first-principles study
Authors: Hao Weijie , Wu Zhigen , Li Xiaobao , Pu Yuxue
Published: May 2021

The edge elasticity and its effect on flexoelectric response of the Janus MoSSe nanoribbons are systematically explored by means of density functional theory based first-principles calculations. We report edge stresses, edge elastic moduli, and structural deformations of the Janus MoSSe nanoribbons with various widths. It is shown that both armchair and zigzag terminated edges of the MoSSe nanoribbons are essentially subjected to tension, due to the existence of the edge stresses. The magnitude of average zigzag edge stresses is much larger than that of the average armchair ones. Furthermore, our results show that both misfit strain induced by asymmetric chalcogen atomic layers, and the edge stresses cause the spontaneous bending deformation of such Janus nanoribbons. More importantly, flexoelectronic properties of semiconducting armchair MoSSe nanoribbons are carefully evaluated and compared with those of armchair MoS2 and MoSTe nanoribbons. In particular, it is found that the out-of-plane flexoelectronic coefficients strongly depend on their widths. Additionally, the flexoelectric response resulting from spontaneous bending is weaker than that from the opposite one. The implicit mechanisms on deformations and flexoelectronic properties of such Janus nanoribbons have been carefully explored. The results in this work provide useful insights into their potential applications in nanoscale electromechanical systems.
A real-time flow forecasting with deep convolutional generative adversarial network: Application to flooding event in Denmark
Authors: Cheng Meiling , Fang Fangxin , Navon I. M. , Pain C. C.
Published: May 2021

Real-time flood forecasting is crucial for supporting emergency responses to inundation-prone regions. Due to uncertainties in the future (e.g., meteorological conditions and model parameter inputs), it is challenging to make accurate forecasts of spatiotemporal floods. In this paper, a real-time predictive deep convolutional generative adversarial network (DCGAN) is developed for flooding forecasting. The proposed methodology consists of a two-stage process: (1) dynamic flow learning and (2) real-time forecasting. In dynamic flow learning, the deep convolutional neural networks are trained to capture the underlying flow patterns of spatiotemporal flow fields. In real-time forecasting, the DCGAN adopts a cascade predictive procedure. The last one-time step-ahead forecast from the DCGAN can act as a new input for the next time step-ahead forecast, which forms a long lead-time forecast in a recursive way. The model capability is assessed using a 100-year return period extreme flood event occurred in Greve, Denmark. The results indicate that the predictive fluid flows from the DCGAN and the high fidelity model are in a good agreement (the correlation coefficient ≥97% and the mean absolute error ≤0.008 m) for a lead-900 time step forecast. This is an important step toward real-time flow forecasting although further evaluation of the DCGAN performance is required in complex realistic cases in the future.
Capsular polysaccharide correlates with immune response to the human gut microbe
Ruminococcus gnavus
Authors: Henke Matthew T. , Brown Eric M. , Cassilly Chelsi D. , Vlamakis Hera , Xavier Ramnik J. , Clardy Jon
Published: May 2021

Significance

Microbes shape human health and disease. Today, there are increasing correlations of gut microbes with specific diseases, but the underlying molecules and mechanism linking the two are not known. This stifles both the understanding of disease causation and the development of suitable treatments. We investigated a dozen patient isolates of
Ruminococcus gnavus
, a prevalent gut microbe linked to inflammatory bowel disease (IBD). We found that some isolates possess a protective capsule that encourages a symbiotic relationship with the host immune system, while others lack this protective capsule and elicit a robust inflammatory immune response. This work reveals a path by which
R. gnavus
could be connected to IBD and potential therapeutic interventions.
The evolution and changing ecology of the African hominid oral microbiome
Authors: Fellows Yates James A. , Velsko Irina M. , Aron Franziska , Posth Cosimo , Hofman Courtney A. , Austin Rita M. , Parker Cody E. , Mann Allison E. , Nägele Kathrin , Arthur Kathryn Weedman , Arthur John W. , Bauer Catherine C. , Crevecoeur Isabelle , Cupillard Christophe , Curtis Matthew C. , Dalén Love , Díaz-Zorita Bonilla Marta , Díez Fernández-Lomana J. Carlos , Drucker Dorothée G. , Escribano Escrivá Elena , Francken Michael , Gibbon Victoria E. , González Morales Manuel R. , Grande Mateu Ana , Harvati Katerina , Henry Amanda G. , Humphrey Louise , Menéndez Mario , Mihailović Dušan , Peresani Marco , Rodríguez Moroder Sofía , Roksandic Mirjana , Rougier Hélène , Sázelová Sandra , Stock Jay T. , Straus Lawrence Guy , Svoboda Jiří , Teßmann Barbara , Walker Michael J. , Power Robert C. , Lewis Cecil M. , Sankaranarayanan Krithivasan , Guschanski Katerina , Wrangham Richard W. , Dewhirst Floyd E. , Salazar-García Domingo C. , Krause Johannes , Herbig Alexander , Warinner Christina
Published: May 2021

Significance

The microbiome plays key roles in human health, but little is known about its evolution. We investigate the evolutionary history of the African hominid oral microbiome by analyzing dental biofilms of humans and Neanderthals spanning the past 100,000 years and comparing them with those of chimpanzees, gorillas, and howler monkeys. We identify 10 core bacterial genera that have been maintained within the human lineage and play key biofilm structural roles. However, many remain understudied and unnamed. We find major taxonomic and functional differences between the oral microbiomes of
Homo
and chimpanzees but a high degree of similarity between Neanderthals and modern humans, including an apparent
Homo
-specific acquisition of starch digestion capability in oral streptococci, suggesting microbial coadaptation with host diet.
CYK-1/Formin activation in cortical RhoA signaling centers promotes organismal left–right symmetry breaking
Authors: Middelkoop Teije C. , Garcia-Baucells Júlia , Quintero-Cadena Porfirio , Pimpale Lokesh G. , Yazdi Shahrzad , Sternberg Paul W. , Gross Peter , Grill Stephan W.
Published: May 2021

Significance

Active torque generation in the actin cytoskeleton has been implicated in driving left–right symmetry breaking of developing embryos, but which molecules generate the active torque and how active torque generation is organized subcellularly remain unclear. This study shows that cortical Formin, recruited to cortical regions where RhoA signaling is active, promotes active torque generation in the actomyosin layer. We find that active torque tends to locally rotate the cortex in a clockwise fashion, which drives the emergence of chiral counterrotating flows with consistent handedness and facilitates left–right symmetry breaking ofC. elegansembryos.
Human-relevant near-organ neuromodulation of the immune system via the splenic nerve
Authors: Donegà Matteo , Fjordbakk Cathrine T. , Kirk Joseph , Sokal David M. , Gupta Isha , Hunsberger Gerald E. , Crawford Abbe , Cook Simon , Viscasillas Jaime , Stathopoulou Thaleia-Rengina , Miranda Jason A. , Dopson Wesley J. , Goodwin David , Rowles Alison , McGill Paul , McSloy Alex , Werling Dirk , Witherington Jason , Chew Daniel J. , Perkins Justin D.
Published: May 2021

Significance

Bioelectronic modulation of the autonomic nervous system innervating the spleen represents a new therapeutic avenue. Studies in rodents suffer from the limitation that stimulation parameters and anatomy are not directly applicable to humans. This work demonstrates the translation of biological mechanisms in a large animal model with similar anatomical, histological, and functional characteristics for derivation of human-relevant parameters. Here, we show the scientific process for translating a bioelectronic medicine to clinical readiness. The results presented can be used in three ways: 1) as a system to demonstrate the species translation of neuroimmune modulation, 2) as an exemplar of how translational models can reveal additional potential mechanisms, and 3) as a general methodology to determine human-relevant stimulation parameters.
Comprehensive pregnancy monitoring with a network of wireless, soft, and flexible sensors in high- and low-resource health settings
Authors: Ryu Dennis , Kim Dong Hyun , Price Joan T. , Lee Jong Yoon , Chung Ha Uk , Allen Emily , Walter Jessica R. , Jeong Hyoyoung , Cao Jingyue , Kulikova Elena , Abu-Zayed Hajar , Lee Rachel , Martell Knute L. , Zhang Michael , Kampmeier Brianna R. , Hill Marc , Lee JooHee , Kim Edward , Park Yerim , Jang Hokyung , Arafa Hany , Liu Claire , Chisembele Maureen , Vwalika Bellington , Sindano Ntazana , Spelke M. Bridget , Paller Amy S. , Premkumar Ashish , Grobman William A. , Stringer Jeffrey S. A. , Rogers John A. , Xu Shuai
Published: May 2021

Significance

Monitoring vital signs for laboring women and their fetuses is foundational to the delivery of obstetrical care; however, monitoring platforms for pregnancy have undergone little innovation over the last several decades with many low-income settings lacking basic access. We report a new time-synchronized, flexible, and wireless sensor system applicable across the entire continuum of antepartum and postpartum care that provides continuous, comprehensive, and noninvasive monitoring (heart rate, respiratory rate, and pulse oxygenation) compatible with a wide range of mobile devices. This system offers advanced features such as continuous blood pressure, uterine electrohysterography, and automated body position classification. We further demonstrate the performance of this new system among pregnant individuals (
n
= 576) in both high-resource settings and low-resource care settings.
Novel functional sequences uncovered through a bovine multiassembly graph
Authors: Crysnanto Danang , Leonard Alexander S. , Fang Zih-Hua , Pausch Hubert
Published: May 2021

Significance

Most sequence variant analyses rely on a linear reference genome that is assumed to lack millions of bases that occur in the genomes of other individuals. To quantify the extent and functional relevance of such missing bases, we integrate six genome assemblies from cattle and related species into a pangenome. This allows us to uncover more than 70 million bases that are not included in the
Bos taurus
reference genome. Through complementary bioinformatics, genomics, and transcriptomics methods, we discover putative genes from nonreference sequences that are differentially expressed and thousands of polymorphic sites that were unused so far. Our work provides a computational framework, broadly applicable to many species, to make a so-far neglected source of genomic variation amenable to genetic investigations.
Stabilized detonation for hypersonic propulsion
Authors: Rosato Daniel A. , Thornton Mason , Sosa Jonathan , Bachman Christian , Goodwin Gabriel B. , Ahmed Kareem A.
Published: May 2021

Significance

There is now an intensifying international effort to develop robust propulsion systems for hypersonic and supersonic flight. Such a system would allow flight through our atmosphere at very high speeds and allow efficient entry and exit from planetary atmospheres. The possibility of basing such a system on detonations, the most powerful form of combustion, has the potential to provide higher thermodynamic efficiency, enhanced reliability, and reduced emissions. This work reports a significant step in attaining this goal: the discovery of an experimental configuration and flow conditions that generate a stabilized oblique detonation, a phenomenon that has the potential to revolutionize high-speed propulsion of the future.
Optical volumetric brain imaging: speed, depth, and resolution enhancement
Authors: Huang Shih-Huan , Irawati Ninik , Chien Yu-Feng , Lin Jyun-Yi , Tsai Yu-Hsuan , Wang Po-Yuan , Chu Li-An , Li Meng-Lin , Chiang Ann-Shyn , Tsia Kevin K , Chu Shi-Wei
Published: May 2021

Understanding how the brain functions is one of the grand challenges in modern scientific research. Similar to a computer, a functional brain is composed of hardware and software. The major bottleneck lies in the difficulty to directly observe the brain ‘software’, i.e. the rule and operating information used by the brain that might emerge from pan-neuron/synapse connectome. A recognized strategy for probing the functional connectome is to perform volumetric imaging in brains with high spatiotemporal resolution and deep brain penetration. Among various imaging technologies, optical imaging offers appealing combinations including spatial resolution of sub-micrometer to nanometer, temporal resolution of second to millisecond, penetration depth of millimeter or deeper, and molecular contrast based on the abundant choices of fluorescent indicators. Thus, it is ideal for enabling three-dimensional functional brain mapping of small animal models. In this review, we focus on recent technological advances in optical volumetric imaging, with an emphasis on the tools and methods for enhancing imaging speed, depth, and resolution. The review could serve as a quantitative reference for physicists and biologists to choose the techniques better suited for specific applications, as well as to stimulate novel technical developments to advance brain research.
Variational hysteresis and photoresponse behavior of MAPbX
3 (X = I, Br, Cl) perovskite single crystals
Authors: Lin Ping , Meng Qingyu , Chen Hang , Hu Haihua , Fang Desheng , Xu Lingbo , Wang Peng , Cui Can
Published: May 2021

High-quality MAPbX
3 (X = I, Br, Cl) single crystals with a desirable size were grown through an inverse temperature crystallization method. Systematically measurements of current–voltage (I–V) hysteresis show that the hysteresis is strongly dependent on the measuring protocol, including scan rate and light illumination condition, which reveals the competition of three main factors that influence the charge dynamics in different regimes, defect trap, MA+ dipoles rotation, and ion migration. In the dark, defect trapping is the dominant charge transport dynamics at low bias in the MAPbI3, while the MA+ dipole rotation is significant in MAPbBr3, and ion migration occurs in MAPbCl3. However, as bias increases, MA+ dipole rotation plays a crucial role in the conductivity either in the dark or under light illumination. The time-dependent photoresponse exhibits different tendencies under various biases. The slow rising dynamics of photoresponse in MAPbX
3 is attributed to the slow rotation of MA+ dipoles, while an immediate overshoot followed by a decay suggests significant ion migration contribution at high external bias. The results serve as comprehensive experimental support to understand the hysteresis behaviors and slow photoresponse in MAPbX
3, particularly in MAPbCl3, and provide a guide for future work in MAPbX
3 based optoelectronic devices.
Atmospheric-pressure CVD growth of two-dimensional 2H- and 1 T′-MoTe2 films with high-performance SERS activity
Authors: Adhikari Bikram , Limbu Tej B , Vinodgopal Kizhanipuram , Yan Fei
Published: May 2021

Two-dimensional (2D) molybdenum ditelluride (MoTe2) is a member of the transition-metal dichalcogenides family, which is an especially promising platform for surface-enhanced Raman scattering (SERS) applications, due to its excellent electronic properties. However, the synthesis of large-area highly crystalline 2D MoTe2 with controllable polymorphism is a huge challenge due to the small free energy difference (∼40 meV per unit cell) between semiconducting 2H-MoTe2 and semi-metallic 1 T′-MoTe2. Herein, we report an optimized route for the synthesis of 2H- and 1 T′-MoTe2 films by atmospheric-pressure chemical vapor deposition. The SERS study of the as-grown MoTe2 films was carried out using methylene blue (MB) as a probe molecule. The Raman enhancement factor on 1 T′-MoTe2 was found to be three times higher than that on 2H-MoTe2 and the 1 T′-MoTe2 film is an efficient Raman-enhancing substrate that can be used to detect MB at nanomolar concentrations. Our study also imparts knowledge on the significance of a suitable combination of laser excitation wavelength and molecule-material platform for achieving ultrasensitive SERS-based chemical detection.
Hierarchically porous piezoresistive sensor for application to the cambered palm of climbing robot with a high payload capacity
Authors: Wang Ziya , Zhu Zhihao , Huang Huayi , Zhao Wenyu , Xu Yingtian , Zheng Zhenliang , Ding Ning
Published: May 2021

Effective sensitivity within a large responding range is a crucial parameter of flexible tactile sensors for a robot, especially for engineering climbing robots under high shear force conditions. While introducing microstructures can improve the sensitivity, in turn, it leads to a limited pressure-response range due to the poor structural compressibility. To achieve effective sensing under large loading forces, the flexible sensor needs to have a hierarchical sensing system and an optimal mechanic design. Herein, we report a strategy of embedded hierarchically porous piezoresistive foam that can significantly boost the sensitivity (S
min > 0.084 kPa−1 at 20 Pa–500 kPa) while simultaneously broadening the pressure responding range, together with remarkable mechanical stability and robustness. Depending on the pressure distribution of the appreciable palm, the climbing robot with a high payload (40 kg) was demonstrated a series of recognitions of obstacles and feedback controls at slipping state. The soft piezoresistive material with the assembly architecture would be a general design expected to be applied to other types of robots to achieve a broader pressure-response range and a higher sensitivity.
Broadband control on scattering events with interferometric coherent waves
Authors: Lee Jeng Yi , Huang Lujun , Xu Lei , Miroshnichenko Andrey E , Lee Ray-Kuang
Published: May 2021

We propose a universal strategy to realize a broadband control on arbitrary scatterers, through multiple coherent beams. By engineering the phases and amplitudes of incident beams, one can suppress the dominant scattering partial waves, making the obstacle lose its intrinsic responses in a broadband spectrum. The associated coherent beams generate a finite and static region, inside which the corresponding electric field intensity and Poynting vector vanish. As a solution to go beyond the sum-rule limit, our methodology is also irrespective of inherent system properties, as well as extrinsic operating wavelength, providing a non-invasive control on the wave-obstacles interaction for any kinds of shape.
General scaling laws of space charge effects in field emission
Authors: Kyritsakis A , Veske M , Djurabekova F
Published: May 2021

The characteristics of field electron and ion emission change when the space charge formed by the emitted charge is sufficient to suppress the extracting electric field. This phenomenon is well described for planar emitting diodes by the one dimensional (1D) theory. Here we generalize for any 3D geometry by deriving the scaling laws describing the field suppression in the weak space charge regime. We propose a novel corrected equivalent planar diode model, which describes the space charge effects for any geometry in terms of the 1D theory, utilizing a correction factor that adjusts the diode’s scaling characteristics. We then develop a computational method, based on the particle-in-cell (PIC) technique, which solves numerically the space charge problem. We validate our theory by comparing it to both our numerical calculations and existing experimental data, either of which can be used to obtain the geometrical correction factor of the corrected equivalent planar diode model.
Fractional vector-borne disease model with lifelong immunity under Caputo operator
Authors: Bulut Hasan , Ilhan Esin
Published: May 2021

This study provides a comprehensive analysis of the vector-borne disease model with lifelong immunity by means of the Caputo fractional differential operator. We present the existence and uniqueness of the solution of the suggested fractional disease model by utilizing the fixed-point theorem. Some basic properties of the non-integer order model such as invariant region, the positiveness of the solution are given under the Caputo derivative. Moreover, analysis of the model shows that disease-free equilibrium is locally asymptotically stable. On the other hand, numerical results with various graphs are presented by taking advantage of different values of non-integer order α. Also, for the disease model under consideration, more detailed results are obtained thanks to the fractional-order derivative as can be seen from the solution curves in the graphs.
Coherent control of magneto-optical Faraday rotation at terahertz frequencies in graphene-based metasurfaces via electromagnetically induced transparency
Authors: Ali Hazrat , Imtiaz Khan M , Ud Din Rafi , Zubair Muhammad , Mahmood Irfan , Ahmad Pervaiz , Ge Guo-Qin
Published: May 2021

We investigate theoretically the controlled magneto-optical Faraday rotation (MO-FR) through graphene-based metasurfaces placed on electromagnetically induced transparency (EIT) substrate at terahertz (THz) frequencies. MO-FR and transmission of the probe light are studied by changing the electric field that manipulates the group index of the substrate. The MO-FR can be controlled and enhanced by varying the periodic width of graphene ribbons. The polarization plane of MO-FR changes with 180 degrees while increasing the probe field detuning through the EIT substrate. The zero-crossing of MO-FR shifts to higher THz frequencies with increasing the magnetic field. The transmission of the probe light pulse at THz frequencies is investigated with the probe detuning and the applied magnetic field.
High-energy picosecond single-pass multi-stage optical parametric generator and amplifier
Authors: Yu Yang , Liu Zhao , Liu Ke , Ma Chao , Gao Hong-Wei , Wang Xiao-Jun , Bo Yong , Cui Da-Fu , Peng Qin-Jun
Published: May 2021

We demonstrate a new management of multi-stage optical parametric generator (OPG) and amplifier (OPA) to obtain high-energy picosecond sources with high beam quality. The setup of multi-stage OPG-OPA requires mode-matching between the pump beam and the stable mode of the OPG-OPA. In a proof-of-principle experiment, the single-pass multi-stage OPG-OPA consists of three walk-off compensated KTP crystal pairs and two lenses, pumped by an 86 ps, 1064 nm 10 kHz picosecond laser. The signal light at ∼ 1.77 μ m has an average output power of 502 mW with record energy up to 50.2 μ J. The beam quality factor of the signal light can be improved to

M
x
2

×

M
y
2

=
1.87
×
2.16

after filtering out about 40% signal power. To the best of our knowledge, it is the first picosecond single-pass multi-stage OPG-OPA pumped at kHz regime.
A low-threshold multiwavelength Brillouin fiber laser with double-frequency spacing based on a small-core fiber*
Authors: Xu Lu-Lu , Wang Ying-Ying , Jiang Li , Yang Pei-Long , Zhang Lei , Dai Shi-Xun
Published: May 2021

We demonstrate multiwavelength Brillouin fiber lasers (MWBFLs) with double-frequency spacing based on a small-core fiber (SCF) and a standard single-mode fiber (SMF), which have core diameters of 5 and 8.8 μm, respectively. Experimental results show that the SCF-based MWBFL exhibits a higher laser output power and a lower pump threshold. The output powers of the SCF-based MWBFL are > 1.4 times those of the SMF-based MWBFL. Moreover, the threshold power required to generate each channel of the SCF-based MWBFL is 59% that of the SMF-based MWBFL. When the same pump power of 180 mW is injected, the number of laser channels generated for the SCF-based MWBFL is 13, which is twice that generated for the SMF-based MWBFL. In addition, the SCF-based MWBFL exhibits good wavelength tunability from 1535 to 1565 nm and temporal stability over an hour.
Improved SIFT algorithm based on image filtering
Authors: Qiao Mingyu , Liang Xiao , Chen Minjie
Published: May 2021

In this paper, SIFT feature extraction algorithm was optimized through image filtering, so as to highlight the role of stable edge corner and improve the efficiency of stable edge corner collection. Afterwards, the experimental results were compared and verified by the FLANN feature matching method. Experimental results show that the improved SIFT feature extraction algorithm using image filtering can improve the extraction effect of feature points with stable edge response, while suppressing the extraction of feature points with unstable edge response, thus improving the accuracy of matching.
Survey of Visual Crowdsensing
Authors: Zhai Shuying , Li Ru
Published: May 2021

In recent years, Visual Crowdsensing (VCS) that sensed through images and video, has become a predominant sensing paradigm of Mobile Crowdsensing (MCS), which is one of the current research hotspots. VCS requires people to capture the details of sensing objects in the real world in the form of pictures or video, which is widely used in various fields. However, there is no article summarizing the development and current situation of VCS. To this end, this paper summarized the latest applications of VCS, including floor plan generation, indoor scene reconstruction, outdoor scene reconstruction, event reconstruction, indoor localization, indoor navigation and disaster relief, and summarized some unique problems of VCS at present.