bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of Machine Learning Techniques for Enuresis Prediction in Children
Authors: Tokar Baran , Baskaya Mukaddes , Celik Ozer , Cemrek Fatih , Acikgoz Ayfer
Published: August 2020

Introduction As a subset of artificial intelligence, machine learning techniques (MLTs) may evaluate very large and raw datasets. In this study, the aim is to establish a model by MLT for the prediction of enuresis in children.

Materials and Methods The study included 8,071 elementary school students. A total of 704 children had enuresis. For analysis of data with MLT, another group including 704 nonenuretic children was structured with stratified sampling. Out of 34 independent variables, 14 with high feature values significantly affecting enuresis were selected. A model of estimation was created by training the data.

Results Fourteen independent variables in order of feature importance value were starting age of toilet training, having urinary urgency, holding maneuvers to prevent voiding, frequency of defecation, history of enuresis in mother and father, having child's own room, parent's education level, history of enuresis in siblings, consanguineous marriage, incomplete bladder emptying, frequent voiding, gender, history of urinary tract infection, and surgery in the past. The best MLT algorithm for the prediction of enuresis was determined as logistic regression algorithm. The total accuracy rate of the model in prediction was 81.3%.

Conclusion MLT might provide a faster and easier evaluation process for studies on enuresis with a large dataset. The model in this study may suggest that selected variables with high feature values could be preferred with priority in any screening studies for enuresis. MLT may prevent clinical errors due to human cognitive biases and may help the physicians to be proactive in diagnosis and treatment of enuresis.
Radiologic Pathologic Correlation of Primary Paratesticular Rhabdomyosarcoma
Authors: Mohan Vignesh Kumar , Ethiraj Dillibabu , Indiran Venkatraman , Pandiaraj Immanuel Judah , Murugan Adarsh , Maduraimuthu Prabakaran
Published: August 2020

Rhabdomyosarcoma is the most common soft tissue sarcoma in childhood and adolescence, arising from the mesenchymal tissue. It is an intrascrotal tumor localized in the paratesticular structures such as the epididymis or spermatic cord. The majority of this tumor occurs in the first two decades of life. Ultrasound is considered the imaging modality of choice for evaluating an intra-scrotal abnormality. We present a case of a 4-year-old boy with a 2-weeks history of rapidly increasing left scrotal swelling which was clinically diagnosed as hydrocoele. We present the ultrasound, elastography and MRI features of a case of paratesticular embryonal rhabdomyosarcoma with pathologic correlation and also emphasize need to consider sarcoma as a differential diagnosis for rapidly growing scrotal swelling.
COVID-19 and Cold Agglutinin Hemolytic Anemia
Authors: Maslov Diana V. , Simenson Victoria , Jain Suma , Badari Ambuga
Published: August 2020

Novel coronavirus disease 2019 (COVID-19) has spread throughout the world and has infected close to 4 million people. It commonly presents with fever, cough, and fatigue. Due to the high inflammatory response, it is suggested that the coagulation cascade is enhanced causing thrombotic events for many patients. We describe a patient with clinical features of cerebrovascular accident, as well as documented blood clots in bilateral upper extremities. Labs revealed the presence of cold agglutinin hemolytic anemia. The association between cold agglutinin autoimmune hemolytic anemia and thrombotic events in COVID-19 patients has not been well investigated. The patient unfortunately passed away within 48 hours after admission. This case stresses the importance of considering a full workup to diagnose autoimmune hemolytic anemia (AIHA) in COVID-19 patients with thromboses and possible implications for management.
Towards a hermeneutic definition of software
Authors: Possati Luca M.
Published: August 2020

The paper intends to establish a comprehensive definition of software from a postphenomenological and hermeneutic point of view. It intends to show the contribution of continental philosophy to the study of new technologies. In section “Introduction: why do we need a comprehensive definition of software?,” I underline the need for a philosophical analysis that can highlight the multifaceted and paradoxical nature of software. In section “Engineering in written form: the five criteria,” starting from some remarks on the history of programming languages, I define a list of minimal requirements (five criteria) that something needs to meet to be qualified as software. All these requirements share two essential features: the written form and the effectiveness, that is, the need to be executed by a physical machine. In section “Software as text: a hermeneutic model,” I focus on software as form of writing. I develop this idea by using Ricoeur’s hermeneutic model. I claim that software is a type of text. In section “The grammatology of microprocessor,” I focus on the second aforementioned feature: the effectiveness of software. I claim that this effectiveness is based on the analogy between electric circuitries and Boolean logic. Software is a writing and re-writing process that implies an interpretation on two levels, epistemological and ontological.
Decay characterization of the solutions to the Navier–Stokes–Voigt equations with damping
Authors: Lyu Wenbin , Lu Liqing , Wu Shaohua
Published: August 2020

The Navier–Stokes–Voigt equations are a regularization of the Navier–Stokes equations. Sharing some asymptotic and statistical properties, they have been used in direct numerical simulations of the latter. In this article, we characterize the decay rate of the solutions to the Navier–Stokes–Voigt equations with damping. Applying the Fourier splitting method, we prove the H1 decay of weak solutions for α > 0, β > 2, and μ > ν2.
Single-pulse (100 ps) extended x-ray absorption fine structure capability at the Dynamic Compression Sector
Authors: Das Pinaki , Klug Jeffrey A. , Sinclair Nicholas , Wang Xiaoming , Toyoda Yoshimasa , Li Yuelin , Williams Brendan , Schuman Adam , Zhang Jun , Turneaure Stefan J.
Published: August 2020

Determining real-time changes in the local atomistic order is important for a mechanistic understanding of shock wave induced structural and chemical changes. However, the single event and short duration (nanosecond times) nature of shock experiments pose challenges in obtaining Extended X-ray Absorption Fine Structure (EXAFS) measurements—typically used for monitoring local order changes. Here, we report on a new single pulse (∼100 ps duration) transmission geometry EXAFS capability for use in laser shock-compression experiments at the Dynamic Compression Sector (DCS), Advanced Photon Source. We used a flat plate of highly oriented pyrolytic graphite (HOPG) as the spectrometer element to energy disperse x rays transmitted through the sample. It provided high efficiency with ∼15% of the x rays incident on the HOPG reaching an x-ray area detector with high quantum efficiency. This combination resulted in a good signal-to-noise ratio (∼103), an energy resolution of ∼10 eV at 10 keV, EXAFS spectra covering 100 s of eV, and a good pulse to pulse reproducibility of our single pulse measurements. Ambient EXAFS spectra for Cu and Au are compared to the reference spectra, validating our measurement system. Comparison of single pulse EXAFS results for ambient and laser shocked Ge(100) shows large changes in the local structure of the short lived state of shocked Ge. The current DCS EXAFS capability can be used to perform single pulse measurements in laser shocked materials from ∼9 keV to 13 keV. These EXAFS developments will be available to all users of the DCS.
Pulsed triple frequency modulation for frequency stabilization and control of two lasers to an optical cavity
Authors: Williams W. D. , Herd M. T. , Cook E. C.
Published: August 2020

We present a method to stabilize two lasers to an optical cavity using pulsed triple frequency modulation. The setup allows simultaneous Pound–Drever–Hall stabilization, as well as independent frequency control, while removing interference terms that limit the frequency scan range and allowing for smaller modulation depths. A review of single, dual, and triple frequency modulation is also presented in addition to a discussion of how to effectively turn pulsed triple frequency modulation into independent dual frequency modulation for each laser. This method would increase the scan range to half the free spectral range.
A magnetohydrodynamic model of a low current vacuum arc jet with a deuterium-impregnated Zr cathode
Authors: Yang Ze , Wang Lijun , Luo Ming , Li Jiagang
Published: August 2020

This work investigates the characteristics of the vacuum arc jet (VAJ) with deuterium-impregnated Zr electrodes. The magnetohydrodynamic model is used considering different components including ions, electrons, and atoms. The radius of the arc root is assumed to be 1–1.5 mm, and thus, the cathode spots and the cathode spot mixing zone are not studied. The density distributions of different components are calculated to obtain the average charge number. Simulation results are discussed to analyze some experimental results. The simulation results show that atom density decreases rapidly near the cathode side. With a more focused beam, the electron temperature increases significantly, leading to more highly charged ions and a higher average charge number. Compared with pure Zr electrodes, deuterium-impregnated electrodes can emit light D ions that can increase the ion velocity and decrease the electron temperature. Therefore, the average charge number of Zr is lower. With more deuterium in the cathode, the arc voltage is lower. However, the arc column cannot change the fraction of deuterium in the VAJ, indicating that the high deuterium fraction in the experiments is caused by the deuterium emitted from the adjacent area of the cathode spots.
An improved ten-moment closure for reconnection and instabilities
Authors: Ng Jonathan , Hakim A. , Wang L. , Bhattacharjee A.
Published: August 2020

The integration of kinetic effects in fluid models is important for global simulations of Earth's magnetosphere. The use of the two-fluid ten-moment model, which includes the pressure tensor for both species, has had some success in simulating Ganymede and Mercury with a simple closure model. We discuss a heat flux closure which accounts for some limitations of the earlier work while remaining computationally tractable. Comparisons with kinetic simulations for magnetic reconnection and lower-hybrid drift instabilities show good agreement with kinetic results and improvements on previous closure models.
Complex excited state polarizabilities in the ADC/ISR framework
Authors: Scheurer Maximilian , Fransson Thomas , Norman Patrick , Dreuw Andreas , Rehn Dirk R.
Published: August 2020

We present the derivation and implementation of complex, frequency-dependent polarizabilities for excited states using the algebraic–diagrammatic construction for the polarization propagator (ADC) and its intermediate state representation. Based on the complex polarizability, we evaluate C6 dispersion coefficients for excited states. The methodology is implemented up to third order in perturbation theory in the Python-driven adcc toolkit for the development and application of ADC methods. We exemplify the approach using illustrative model systems and compare it to results from other ab initio methods and from experiments.
Parametric excitation induced extreme events in MEMS and Liénard oscillator
Authors: Suresh R. , Chandrasekar V. K.
Published: August 2020

Two paradigmatic nonlinear oscillatory models with parametric excitation are studied. The authors provide theoretical evidence for the appearance of extreme events (EEs) in those systems. First, the authors consider a well-known Liénard type oscillator that shows the emergence of EEs via two bifurcation routes: intermittency and period-doubling routes for two different critical values of the excitation frequency. The authors also calculate the return time of two successive EEs, defined as inter-event intervals that follow Poisson-like distribution, confirming the rarity of the events. Further, the total energy of the Liénard oscillator is estimated to explain the mechanism for the development of EEs. Next, the authors confirmed the emergence of EEs in a parametrically excited microelectromechanical system. In this model, EEs occur due to the appearance of a stick-slip bifurcation near the discontinuous boundary of the system. Since the parametric excitation is encountered in several real-world engineering models, like macro- and micromechanical oscillators, the implications of the results presented in this paper are perhaps beneficial to understand the development of EEs in such oscillatory systems.
Mixed quantum–classical approach to model non-adiabatic electron–nuclear dynamics: Detailed balance and improved surface hopping method
Authors: Stolyarov E. V. , White A. J. , Mozyrsky D.
Published: August 2020

We develop a density matrix formalism to describe coupled electron–nuclear dynamics. To this end, we introduce an effective Hamiltonian formalism that describes electronic transitions and small (quantum) nuclear fluctuations along a classical trajectory of the nuclei. Using this Hamiltonian, we derive equations of motion for the electronic occupation numbers and for the nuclear coordinates and momenta. We show that, in the limit, when the number of nuclear degrees of freedom coupled to a given electronic transition is sufficiently high (i.e., the strong decoherence limit), the equations of motion for the electronic occupation numbers become Markovian. Furthermore, the transition rates in these (rate) equations are asymmetric with respect to the lower-to-higher energy transitions and vice versa. In thermal equilibrium, such asymmetry corresponds to the detailed balance condition. We also study the equations for the electronic occupations in the non-Markovian regime and develop a surface hopping algorithm based on our formalism. To treat the decoherence effects, we introduce additional “virtual” nuclear wave packets whose interference with the “real” (physical) wave packets leads to the reduction in coupling between the electronic states (i.e., decoherence) as well as to the phase shifts that improve the accuracy of the numerical approach. Remarkably, the same phase shifts lead to the detailed balance condition in the strong decoherence limit.
Interactions at engineered graft–tissue interfaces: A review
Authors: Zhu Wenzhen , Nie Xiaolei , Tao Qi , Yao Hang , Wang Dong-An
Published: August 2020

The interactions at the graft–tissue interfaces are critical for the results of engraftments post-implantation. To improve the success rate of the implantations, as well as the quality of the patients' life, understanding the possible reactions between artificial materials and the host tissues is helpful in designing new generations of material-based grafts aiming at inducing specific responses from surrounding tissues for their own reparation and regeneration. To help researchers understand the complicated interactions that occur after implantations and to promote the development of better-designed grafts with improved biocompatibility and patient responses, in this review, the topics will be discussed from the basic reactions that occur chronologically at the graft–tissue interfaces after implantations to the existing and potential applications of the mechanisms of such reactions in designing of grafts. It offers a chance to bring up-to-date advances in the field and new strategies of controlling the graft–tissue interfaces.
Turbulence, pseudo-turbulence, and local flow topology in dispersed bubbly flow
Authors: Chu Xu , Liu Yanchao , Wang Wenkang , Yang Guang , Weigand Bernhard , Nemati Hassan
Published: August 2020

Bubbly turbulent flow in a channel is investigated using interface-resolved direct numerical simulation. An efficient coupled level-set volume-of-fluid solver based on a fast Fourier transform algorithm is implemented to enable a high resolution and fast computation at the same time. Up to 384 bubbles are seeded in the turbulent channel flow corresponding to 5.4% gas volume fraction. Bubbles are clustered in the channel center due to the downward flow direction. The bubbles induce additional pseudo-turbulence in the channel center and are also able to attenuate the energy in the boundary layer by reducing the shear production. Turbulent kinetic energy budget indicates a significant buoyancy production in the channel center. A local equilibrium between buoyancy production and dissipation is observed here besides the shear production peak in the boundary layer. Comparing the local production and dissipation indicates a coexistence of boundary layer turbulence near the wall and bubble-induced pseudo-turbulence in the channel center. The liquid phase and gas phase are coupled through the complex liquid–gas interface. Local flow topology analysis is depicted in the liquid phase around the bubbles as well as in the gas phase. The flow topology of the liquid phase and the gas phase differs from each other significantly. Local dissipation is more dominant in the liquid phase near the bubble interface, whereas local enstrophy is preferred in the gas phase. In the liquid phase, a high dissipation event is preferred close to the interface, whereas a high enstrophy event is dominant away from the interface.
Range-separated stochastic resolution of identity: Formulation and application to second-order Green’s function theory
Authors: Dou Wenjie , Chen Ming , Takeshita Tyler Y. , Baer Roi , Neuhauser Daniel , Rabani Eran
Published: August 2020

We develop a range-separated stochastic resolution of identity (RS-SRI) approach for the four-index electron repulsion integrals, where the larger terms (above a predefined threshold) are treated using a deterministic RI and the remaining terms are treated using a SRI. The approach is implemented within a second-order Green’s function formalism with an improved O(N3) scaling with the size of the basis set, N. Moreover, the RS approach greatly reduces the statistical error compared to the full stochastic version [T. Y. Takeshita et al., J. Chem. Phys. 151, 044114 (2019)], resulting in computational speedups of ground and excited state energies of nearly two orders of magnitude, as demonstrated for hydrogen dimer chains and water clusters.
Phase transition in epitaxial bismuth nanofilms
Authors: He Feng , Walker Emily S. , Zhou Yongjian , Montano Raul D. , Bank Seth R. , Wang Yaguo
Published: August 2020

Raman and coherent phonon spectroscopies were used to investigate the thickness-dependent phononic properties of ultrathin single-crystal Bi films prepared by molecular beam epitaxy on Si(111) substrates. Both the A1g and Eg Raman peaks disappeared in the Raman spectra of a 4 nm Bi film, indicating a complete transition from the low-symmetry A7 structure to the high-symmetry A17 structure. Coherent phonon signals of the A1g mode also showed a strong dependence on the film thickness, where thin samples (≤15 nm) exhibited lower phonon frequency and shorter phonon lifetimes than the thick samples (≥30 nm). This difference is attributed to a shallower energy potential barrier caused by both a permanent phase transition, which is determined by the film thickness, and a temporary structural transition by photo-excited carriers. Our results not only provide evidence of a phase transition from the A7 to the A17 structure with the decreasing Bi film thickness but also reveal the influence of this phase transition on phonon dynamics. Understanding these material performance traits will facilitate modern application of Bi thin films in electronic devices.
Epitaxial stabilization of rutile germanium oxide thin film by molecular beam epitaxy
Authors: Chae S. , Paik H. , Vu N. M. , Kioupakis E. , Heron J. T.
Published: August 2020

Ultrawide bandgap (UWBG) semiconductors (Eg >3 eV) have tremendous potential for power-electronic applications. The current state-of-the-art UWBG materials such as β-Ga2O3, diamond, and AlN/AlGaN, however, show fundamental doping and thermal conductivity limitations that complicate technological adaption and motivate the search for alternative materials with superior properties. Rutile GeO2 (r-GeO2) has been theoretically established to have an ultrawide bandgap (4.64 eV), high electron mobility, high thermal conductivity (51 W m−1 K−1), and ambipolar dopability. While single-crystal r-GeO2 has been synthesized in bulk, the synthesis of r-GeO2 thin films has not been previously reported but is critical to enable microelectronics applications. Here, we report the growth of single-crystalline r-GeO2 thin films on commercially available R-plane sapphire substrates using molecular beam epitaxy. Due to a deeply metastable glass phase and high vapor pressure of GeO, the growth reaction involves the competition between absorption and desorption as well as rutile and amorphous formation. We control the competing reactions and stabilize the rutile-phase growth by utilizing (1) a buffer layer with reduced lattice misfit to reduce epitaxial strain and (2) the growth condition that allows the condensation of the preoxidized molecular precursor yet provides sufficient adatom mobility. The findings advance the synthesis of single-crystalline films of materials prone to glass formation and provide opportunities to realize promising ultra-wide-bandgap semiconductors.
Dense networks that do not synchronize and sparse ones that do
Authors: Townsend Alex , Stillman Michael , Strogatz Steven H.
Published: August 2020

Consider any network of n identical Kuramoto oscillators in which each oscillator is coupled bidirectionally with unit strength to at least μ(n−1) other oscillators. Then, there is a critical value of μ above which the system is guaranteed to converge to the in-phase synchronous state for almost all initial conditions. The precise value of μ remains unknown. In 2018, Ling, Xu, and Bandeira proved that if each oscillator is coupled to at least 79.29% of all the others, global synchrony is ensured. In 2019, Lu and Steinerberger improved this bound to 78.89%. Here, we find clues that the critical connectivity may be exactly 75%. Our methods yield a slight improvement on the best known lower bound on the critical connectivity from 68.18% to 68.28%. We also consider the opposite end of the connectivity spectrum, where the networks are sparse rather than dense. In this regime, we ask how few edges one needs to add to a ring of n oscillators to turn it into a globally synchronizing network. We prove a partial result: all the twisted states in a ring of size n=2m can be destabilized by adding just O(nlog2⁡n) edges. To finish the proof, one needs to rule out all other candidate attractors. We have done this for n≤8 but the problem remains open for larger n. Thus, even for systems as simple as Kuramoto oscillators, much remains to be learned about dense networks that do not globally synchronize and sparse ones that do.
Effect of channel thickness on noise in organic electrochemical transistors
Authors: Polyravas Anastasios G. , Schaefer Nathan , Curto Vincenzo F. , Calia Andrea Bonaccini , Guimera-Brunet Anton , Garrido Jose A. , Malliaras George G.
Published: August 2020

Organic electrochemical transistors (OECTs) have been widely used as transducers in electrophysiology and other biosensing applications. Their identifying characteristic is a transconductance that increases with channel thickness, and this provides a facile mechanism to achieve high signal amplification. However, little is known about their noise behavior. Here, we investigate noise and extract metrics for the signal-to-noise ratio and limit of detection in OECTs with different channel thicknesses. These metrics are shown to improve as the channel thickness increases, demonstrating that OECTs can be easily optimized to show not only high amplification, but also low noise.
Quantification of convective and diffusive transport during CO2 dissolution in oil: A numerical and analytical study
Authors: Doranehgard Mohammad Hossein , Dehghanpour Hassan
Published: August 2020

In this study, we use an analytical approach and the interpolation-supplemented lattice Boltzmann method (ISLBM) to quantify convective and diffusive transport during CO2 dissolution. In the first step, we use a turbulence analogy and the ISLBM to determine the relationship between the Rayleigh number (Ra) and the ratio of the pseudo-diffusion coefficient to the molecular diffusion coefficient (D*D). We then use experimental data from two oil samples, condensate and crude oils, to validate the obtained relationship between D*D and Ra. We also use the Sherwood number (Sh) and total mixing and diffusive transport curves to analyze different periods during CO2 dissolution for condensate and crude oils. We focus, in particular, on how Ra affects the characteristics of density-driven fingers and the convection field. Our results show that there is a logarithmic trend between D*D and Ra. Analysis of the total mixing and diffusive curves indicates that the CO2 dissolution process can be divided into three distinct periods, namely, diffusive transport, early convection, and late convection. We find that more than 50% of the ultimate CO2 dissolution occurs in the early convection period. We also show that the analytical results obtained for the critical time and critical depth at the onset of convection is in good agreement with those of the ISLBM. After the onset of convection, the formation of initial fingers leads to enhanced convective transport, with marked implications for the concentration variance and mixing rate.
Who uses residential aged care now, how has it changed and what does it mean for the future?
Authors: Gibson Diane
Published: August 2020

ObjectiveThis paper presents past trends in resident characteristics and usage patterns in residential aged care and explores implications for the future.
MethodsTime series analyses were undertaken of national aged care administrative datasets and the Australian Bureau of Statistics Surveys of Disability, Ageing and Carers.
ResultsAlthough the number of people in residential care has continued to increase, resident profiles have changed as a result of higher growth rates in the number of men and of people aged 65–74 years and 90 years and over, and a decline in the number of women aged 75–89 years. Relative to population size, usage rates are declining across all age groups, the average length of stay is shortening, and dependency levels appear to be rising.
ConclusionChanging trends in residential aged care use, when combined with key trends in the broader population of older Australians, offer useful insights in planning for the future.
What is known about the topic?Trends in the changing characteristics of permanent aged care residents and patterns of use of Australian residential aged care have received sparse attention in scholarly journals. Government reports and databases contain useful statistics, but they do not provide a coherent analysis and interpretation of the implications of these trends or situate them in broader population patterns.
What does this paper add?The analyses in this paper demonstrate patterns of change and continuity in the use of residential care over the past decade, and locate those changes in the context of broader trends in the ageing population. Together, this provides useful insights into current and likely future trends, as well as a basis for imagining an improved residential aged care system in the future.
What are the implications for practitioners?These analyses illustrate how data on aged care services, demographic trends and disease patterns can be used to consider the challenges that have affected our residential aged care system in the past and how that may be addressed in the future.
LIN28B/
let-7
control the ability of neonatal murine auditory supporting cells to generate hair cells through mTOR signaling
Authors: Li Xiao-Jun , Doetzlhofer Angelika
Published: August 2020

Significance

Cochlear hair cell loss is a leading cause of deafness in humans and other mammals. In the immature cochlea, lost hair cells are regenerated by neighboring glia-like supporting cells. However, for reasons unknown, such regenerative capacity is rapidly lost as supporting cells undergo maturation. Here we identify a direct link between LIN28B, mammalian target of rapamycin (mTOR) activity, and supporting cell plasticity. Mimicking later developmental stages, we found that loss of the RNA binding protein LIN28B attenuated mTOR signaling and rendered young, immature supporting cells incapable of producing hair cells. Conversely, we found that reexpression of LIN28B reinstated the ability of maturing supporting cells to revert to a progenitor-like state and generate hair cells via activation of mTOR signaling.
Estimating unobserved SARS-CoV-2 infections in the United States
Authors: Perkins T. Alex , Cavany Sean M. , Moore Sean M. , Oidtman Rachel J. , Lerch Anita , Poterek Marya
Published: August 2020

Significance

In early 2020, delays in availability of diagnostic testing for COVID-19 prompted questions about the extent of unobserved community transmission in the United States. We quantified unobserved infections in the United States during this time using a stochastic transmission model. Although precision of our estimates is limited, we conclude that many more thousands of people were infected than were reported as cases by the time a national emergency was declared and that fewer than 10% of locally acquired, symptomatic infections in the United States may have been detected over a period of a month. This gap in surveillance during a critical phase of the epidemic resulted in a large, unobserved reservoir of infection in the United States by early March.
The paradoxical lean phenotype of hypothyroid mice is marked by increased adaptive thermogenesis in the skeletal muscle
Authors: Kaspari Rachel R. , Reyna-Neyra Andrea , Jung Lara , Torres-Manzo Alejandra Paola , Hirabara Sandro M. , Carrasco Nancy
Published: August 2020

Significance

The rate of obesity is steadily increasing in the United States and around the world, which is a major health concern, as weight gain is strongly associated with many leading causes of death. Although recent findings have deepened our understanding of the mechanisms underlying obesity, there is still a lack of therapeutic targets for inducing weight loss. We have found that a drug-free mouse model of hypothyroidism is paradoxically leaner than euthyroid controls. Here, we show that hypothyroid mice consume less food and display strikingly higher levels of skeletal-muscle adaptive thermogenesis. Our findings yield insights into the physiological adaptations that occur in hypothyroidism and may eventually help bring to light new targets for promoting weight loss.
Broad host range of SARS-CoV-2 predicted by comparative and structural analysis of ACE2 in vertebrates
Authors: Damas Joana , Hughes Graham M. , Keough Kathleen C. , Painter Corrie A. , Persky Nicole S. , Corbo Marco , Hiller Michael , Koepfli Klaus-Peter , Pfenning Andreas R. , Zhao Huabin , Genereux Diane P. , Swofford Ross , Pollard Katherine S. , Ryder Oliver A. , Nweeia Martin T. , Lindblad-Toh Kerstin , Teeling Emma C. , Karlsson Elinor K. , Lewin Harris A.
Published: August 2020

Significance

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of COVID-19, a major pandemic that threatens millions of human lives and the global economy. We identified a large number of mammals that can potentially be infected by SARS-CoV-2 via their ACE2 proteins. This can assist the identification of intermediate hosts for SARS-CoV-2 and hence reduce the opportunity for a future outbreak of COVID-19. Among the species we found with the highest risk for SARS-CoV-2 infection are wildlife and endangered species. These species represent an opportunity for spillover of SARS-CoV-2 from humans to other susceptible animals. Given the limited infectivity data for the species studied, we urge caution not to overinterpret the predictions of the present study.
An experimental study of the effect of close reading versus casual reading of social drama on the stimulation of the cognitive capacity of empathy
Authors: Karam Khaled Mostafa , Elfiel Helmy
Published: August 2020

The current study investigates whether the mode of reading practice has an effect on the degree of readers’ empathic response to social drama, using Enda Walsh’sChatroom(2015), tackling contemporary adolescents’ problems, as an experimental example. The experiment conducted in this paper hypothesizes that in contrast with casual reading, the conscious techniques of close reading are more effective in promoting participants’ empathic engagement with the dramatic text and improving their capacity of problem discovery and solution. Accordingly, the close reading of social drama can reinforce social integration and work as an antidote to the ostracism of one social group from their community. Moreover, the L2 students’ stimulated empathic response is translated into a written output which is richer in quantity and quality.
A scoping review of published literature on mathematical modelling for chikungunya.
Authors: Berthiaume Philippe , Côté Jean-Charles , Mascarenhas Mariola
Published: August 2020

Chikungunya is a disease caused by the chikungunya virus (CHIKV), a mosquito-borne alphavirus that is emerging and re-emerging in different parts of the world. Urban expansion, globalization, increase in human travel and tourism are some of the factors increasing the risk of importation of the disease in new areas. Furthermore, climate change is modifying the environmental suitability for the establishment of CHIKV vectors and can add to the risk for the autochthonous transmission of chikungunya in many geographical areas. In a recent scoping review (ScR), the literature published on chikungunya until January 2017 was broadly categorized according to different research areas. The results presented here focus exclusively on the 103 articles categorized under mathematical modelling. All 103 articles were revisited and further reclassified into four non-exclusive categories based on their methodology - disease transmission modelling, mathematical equations used to perform risk assessment, vector mapping and burden of disease assessment. A new data characterization form was devised, which included specific sets of questions tailored to each category. Extracted data were analysed and our results show that over the last 20 years, there has been a significant increase in the number of publications on chikungunya transmission modelling, or using mathematical equations to perform risk assessment, vector mapping and burden of disease assessment. A total of 76 articles have contributed information on disease transmission modelling, 37 on risk assessment, 20 on vector mapping and eight on burden of disease. Data including the specific purpose of the models, methods used, geographical areas targeted and main results from each article were identified and collated.
Characterization of systematic error in Advanced LIGO calibration
Authors: Sun Ling , Goetz Evan , Kissel Jeffrey S , Betzwieser Joseph , Karki Sudarshan , Viets Aaron , Wade Madeline , Bhattacharjee Dripta , Bossilkov Vladimir , Covas Pep B , Datrier Laurence E H , Gray Rachel , Kandhasamy Shivaraj , Lecoeuche Yannick K , Mendell Gregory , Mistry Timesh , Payne Ethan , Savage Richard L , Weinstein Alan J , Aston Stuart , Buikema Aaron , Cahillane Craig , Driggers Jenne C , Dwyer Sheila E , Kumar Rahul , Urban Alexander
Published: August 2020

The raw outputs of the detectors within the Advanced Laser Interferometer Gravitational-Wave Observatory need to be calibrated in order to produce the estimate of the dimensionless strain used for astrophysical analyses. The two detectors have been upgraded since the second observing run and finished the year-long third observing run. Understanding, accounting, and/or compensating for the complex-valued response of each part of the upgraded detectors improves the overall accuracy of the estimated detector response to gravitational waves. We describe improved understanding and methods used to quantify the response of each detector, with a dedicated effort to define all places where systematic error plays a role. We use the detectors as they stand in the first half (six months) of the third observing run to demonstrate how each identified systematic error impacts the estimated strain and constrain the statistical uncertainty therein. For this time period, we estimate the upper limit on systematic error and associated uncertainty to be <7% in magnitude and <4 deg in phase (68% confidence interval) in the most sensitive frequency band 20–2000 Hz. The systematic error alone is estimated at levels of <2% in magnitude and <2 deg in phase.
Singularity resolution depends on the clock
Authors: Gielen Steffen , Menéndez-Pidal Lucía
Published: August 2020

We study the quantum cosmology of a flat Friedmann–Lemaître–Robertson–Walker Universe filled with a (free) massless scalar field and a perfect fluid that represents radiation or a cosmological constant whose value is not fixed by the action, as in unimodular gravity. We study two versions of the quantum theory: the first is based on a time coordinate conjugate to the radiation/dark energy matter component, i.e., conformal time (for radiation) or unimodular time. As shown by Gryb and Thébault, this quantum theory achieves a type of singularity resolution; we illustrate this and other properties of this theory. The theory is then contrasted with a second type of quantisation in which the logarithm of the scale factor serves as time, which has been studied in the context of the ‘perfect bounce’ for quantum cosmology. Unlike the first quantum theory, the second one contains semiclassical states that follow classical trajectories and evolve into the singularity without obstruction, thus showing no singularity resolution. We discuss how a complex scale factor best describes the semiclassical dynamics. This cosmological model serves as an illustration of the problem of time in quantum cosmology.
Solitary choanoflagellate dynamics and microconfined directed transport
Authors: Sparacino Javier , Miño Gastón L , Banchio Adolfo J , Marconi V I
Published: August 2020

In evolutionary biology, choanoflagellates are broadly investigated as the closest animal ancestors. Under suitable environmental cues, choanoflagellate Salpingoeca rosetta can differentiate into two types of solitary motile cells. Each group is recognized by its own strategy to swim and its morphology. Moreover, under nutrient limited conditions, S. rosetta experience a haploid-to-diploid transition evidenced by the presence of gametes. It is challenging to determine if there is a connection between the two types of swimming strategies and the male and female gametes. Therefore a current interest is to isolate and concentrate the fast swimming cells, for instance, using a microfluidic device. Following this aim we measured their body sizes and characterized their motilities. We determined that fast cells swim remarkably different from slow cells and proposed a phenomenological model to reproduce the observed dynamics. We solved the Langevin dynamical equations of motion using experimental parameters for choanoflagellates swimming in a confined flat microdevice divided by a wall of asymmetric obstacles. A systematic study of the directed transport efficiency was performed in order to optimize the geometry of the obstacles wall. Numerical results showed that fast choanoflagellates can be directed efficiently for a wide range of geometric parameters of the obstacles wall while slow cells are hardly directed independently of its geometry. The clear differences found in the rectification of fast and slow choanoflagellates suggest that an efficient micro-sorter device could be designed for further applications in evolutionary biology.
Zones optimized multilevel diffractive lens for polarization-insensitive light focusing
Authors: Yildirim Bumin K , Bor Emre , Kurt Hamza , Turduev Mirbek
Published: August 2020

In this study, we present the numerical design and experimental demonstration of an all-dielectric low refractive index polarization-insensitive multilevel diffractive lens (MDL) at microwave frequencies. The proposed MDL structure is composed of concentric rings (zones) having different widths and heights. Here, the heights and widths of each dielectric concentric rings of lens structure are optimized by using the differential evolution (DE) algorithm to obtain the desired polarization-insensitive focusing performance. The DE method is incorporated with the three-dimensional finite-difference time-domain method to design an MDL structure and evaluate its wave focusing ability. The design frequency is fixed to 10 GHz and, at the design frequency, the DE method is applied to achieve light focusing with the full-width at half-maximum (FWHM) values of 0.654λ and 0.731λ for transverse-magnetic (TM) and transverse-electric (TE) polarizations, respectively, where λ is the wavelength of incident light in free space. Moreover, focusing efficiencies and numerical apertures are calculated as 60.3% and 0.853 at the design frequency, respectively, for both polarizations. Besides, experimental verifications of the numerical results are carried out in microwave regime where the MDL design is fabricated by 3D printing technology by using a polylactic acid material. In the microwave experiments, MDL focuses the TM and TE polarized waves at the focal distances of 71.82 mm and 69.3 mm with the FWHM values of 0.701λ and 0.887λ, respectively. We believe that the proposed design approach can be further expanded to design low refractive index lenses for visible and near-infrared wavelengths.
Strongly trapping soluble lithium polysulfides using polar cysteamine groups for highly stable lithium sulfur batteries
Authors: Shen Xiaowei , Xu Na , Liu Xuejun , Liu Jie , Qian Tao , Yan Chenglin
Published: August 2020

Sulfur has become one of the most promising positive electrode materials for lithium sulfur batteries due to its high theoretical capacity and high energy density (2500 Wh kg−1). The use of common nonpolar carbon/sulfur composites has proved to be a good way to improve the performance, but they still cannot efficiently trap highly polar lithium polysulfides due to the weak interactions between nonpolar carbon and polar polysulfides. Herein, we report a new strategy of using polar cysteamine groups to trap polar polysulfides, leading to greatly enhanced capacity of ∼920 mAh g−1 at 1 C with a high Coulombic efficiency of ∼99.1%, and a long cycle life of over 600 cycles with a capacity retention higher than 80%. Importantly, in situ UV/Vis spectroscopy was employed to identify intermediates during cycling, which demonstrates the constructed unique polar cysteamine functionalized carbon nanotubes (CNTs) can greatly reduce the production of polysulfides and suppress the shuttle effect. The broken-bond model of linear polysulfane during cycling was further demonstrated by density functional theory calculations. The present strategy of using polar cysteamine-functionalized CNTs to trap soluble intermediates is promising and has significant potential for the development of highly efficient lithium sulfur batteries.
RAQ: a novel surrogate for the craniospinal pressure–volume relationship
Authors: Spiegelberg Andreas , Krause Matthias , Meixensberger Juergen , Kurtcuoglu Vartan
Published: August 2020

Objective: The intracranial pressure–volume relation contains information relevant for diagnostics of hydrocephalus and other space-occupying pathologies. We aimed to design a noise-resilient surrogate for this relationship that can be calculated from intracranial pressure (ICP) signals. Approach: The new surrogate, termed respiratory amplitude quotient (RAQ), characterizes the modulation of the cardiac pulse wave amplitude by the respiratory wave in the ICP time course. RAQ is defined as the ratio of the amplitude of the respiratory wave in the ICP signal to the amplitude of the respiration-induced variation in the course of the cardiac pulse wave amplitude. We validated the calculation of RAQ on synthetically generated ICP waveforms. We further extracted RAQ retrospectively from overnight ICP recordings in a cohort of hydrocephalus patients with aqueductal stenosis, age 55.8 ± 18.0 years, and a comparison group with hydrocephalus diagnosed by morphology in MRI, but not responsive to either external lumbar drainage or ventriculo-peritoneal shunting, age 72.5 ± 6.1 years. RAQ was determined for the full recordings, and separately for periods containing B-waves. Main results: We found a mean difference of less than 2% between the calculated values of RAQ and the theoretically determined equivalent descriptors of the synthetic ICP waveforms. In the overnight recordings, we found significantly different RAQ values during B-waves in the aqueductal stenosis (0.86 ± 0.11) and non-responsive hydrocephalus patient groups (1.07 ± 0.20), p = 0.027. In contrast, there was no significant difference in other tested parameters, namely pressure–volume index, elastance coefficient, and resistance to outflow. Neither did we find significant difference when considering RAQ over the full recordings. Significance: Our results indicate that RAQ may function as a potential surrogate for the intracranial pressure–volume relation.
Experimental validation of solar-panel-tied three-port switched-inductor-based dual-boost DC–DC-converter-fed three-phase micro-inverter
Authors: Kamalathiyagarajan S , Chitra Selvi S
Published: August 2020

This paper proposes a solar-panel-integrated modified high-gain three-port dual-boost switched-inductor-based DC–DC-converter-operated micro-inverter for grid-connected applications. Solar-panel-integrated grid-connected micro-inverters need a high-gain front-end DC–DC converter to regulate and step up the output voltage of the solar panels. The proposed three-port dual-boost DC–DC converter offers high voltage gain at low duty ratio and efficiently transfers the power produced by the solar panel to the utility grid. The power losses and steady-state analysis of the proposed converter working in continuous conduction mode are examined. Examinations among the conventional boost converter are presented, and it is discovered that the proposed converter has the largest voltage transformation. Finally, the results obtained from simulated and experimental prototype models are presented to confirm the power conversion capability of the proposed converter.
Theoretical analysis of carrier heating effect in quantum-dot semiconductor lasers based on a multi-level energy balance equations model
Authors: Yousefvand Hossein Reza
Published: August 2020

In this paper, we develop a self-consistent numerical approach for quantum-dot (QD) semiconductor lasers which enables us to dynamically describe the charge-carrier temperature in the wetting layer (WL) and within the QDs during the laser operation. The self-consistent analysis of the WL-QD system is performed using an asymmetric multi-population rate-equation model with a multi-level energy balance equations approach. An important aspect of the model is that the carrier scattering dynamics in the combined WL-QD system is described by Coulomb scattering rates, and these rates are incorporated into the laser dynamical equations as nonlinear functions of the electron and hole densities in the WL. Using the presented model, the impact of carrier heating on the steady-state, turn-on dynamics and small-signal modulation response of QD lasers is investigated. As a main result it is shown that the carrier temperature in the WL is sufficiently higher than the carrier temperature inside the QDs, because the WL is the main origin of all carrier–carrier collisions in the system and, it not only acts as a carrier reservoir for QDs but can also inhibit the carrier heating inside the QDs.