bluuebunny/crossref_metadata_2025 huggingface dataset:
Inpatient Opioid Consumption Variability following Total Knee Arthroplasty: Analysis of 4,038 Procedures
Authors: Roof Mackenzie A. , Sullivan Connor W. , Feng James E. , Anoushiravani Afshin A. , Waren Daniel , Friedlander Scott , Lajam Claudette M. , Schwarzkopf Ran , Slover James D.
Published: April 2020

This study examined an early iteration of an inpatient opioid administration-reporting tool, which standardized patient opioid consumption as an average daily morphine milligram equivalence per surgical encounter (MME/day/encounter) among total knee arthroplasty (TKA) recipients. The objective was to assess the variability of inpatient opioid administration rates among surgeons after implementation of a multimodal opioid sparing pain protocol. We queried the electronic medical record at our institution for patients undergoing elective primary TKA between January 1, 2016 and June 30, 2018. Patient demographics, inpatient and surgical factors, and inpatient opioid administration were retrieved. Opioid consumption was converted into average MME for each postoperative day. These MME/day/encounter values were used to determine mean and variance of opioids prescribed by individual surgeons. A secondary analysis of regional inpatient opioid consumption was determined by patient zip codes. In total, 23 surgeons performed 4,038 primary TKA. The institutional average opioid dose was 46.24 ± 0.75 MME/day/encounter. Average intersurgeon (IS) opioid prescribing ranged from 17.67 to 59.15 MME/day/encounter. Intrasurgeon variability ranged between ± 1.01 and ± 7.51 MME/day/encounter. After adjusting for patient factors, the average institutional MME/day/encounter was 38.43 ± 0.42, with average IS variability ranging from 18.29 to 42.84 MME/day/encounter, and intrasurgeon variability ranging between ± 1.05 and ± 2.82 MME/day/encounter. Our results suggest that there is intrainstitutional variability in opioid administration following primary TKA even after controlling for potential patient risk factors. TKA candidates may benefit from the implementation of a more rigid standardization of multimodal pain management protocols that can control pain while minimizing the opioid burden. This is a level of evidence III, retrospective observational analysis.
Progressive Supranuclear Palsy: A Crucial Co-occurrence in Normal Pressure Hydrocephalus or an Etiology of Hydrocephalic Presentation?
Authors: Onder Halil
Published: April 2020

Co-occurrences of neurodegenerative diseases in normal pressure hydrocephalus (NPH) is a remarkable topic of discussion, which has been mentioned in recent studies and it was also emphasized by the International Society for Hydrocephalus and Cerebrospinal Fluid Disorder. In this report, I illustrate two remarkable cases which were initially diagnosed with idiopathic normal pressure hydrocephalus (iNPH) and ventriculoperitoneal (VP) shunt surgery was performed, which yielded significant improvement in the clinic of both patients in the short-term period. However, in the long-term follow-up, both of them deteriorated, and re-evaluation of the neurological examination and neuroimaging data yielded the full clinical picture of progressive supranuclear palsy (PSP). Via the illustration of these cases and related literature data, I rediscuss some related hypotheses about the co-occurrence of these two conditions of hydrocephalus and PSP. I also suggest some distinct discussions to be clarified in future studies.
Superior Mesenteric Artery Thrombosis; Rare complication after Pancreaticoduodenectemy
Authors: Jindal Satyaprakash , K. Adithya G. , Hukkeri Vachan , Madaan Varun , Vohra Sandeep , Tandon Vivek , Govil Deepak ,   Chitra
Published: April 2020

Pancreaticoduodenectemy(PD) is the treatment of choice for malignant and some benign diseases of the pancreas and periampullary region. Common complications after PD include delayed gastric emptying, pancreatic fistula, anastomotic leak and intra abdominal collection. Postoperative medical complications include arrhythmia, renal failure, pulmonary complications, UTI and Deep vein thrombosis. Superior mesenteric artery (SMA) thrombosis is rarely been reported after PD. There is theoretical possibility of arterial thrombosis in patient with history of vascular disease, which may precipitate after postoperative hypovolemia. SMA thrombosis is difficult to diagnose in postoperative period due to nonspecific symptoms and associated with high mortality rate up to 80-90%. Our patient was a 68 years old female with lower end cholangiocarcinoma without any other co-morbidity. She underwent PD without any intraoperative complications. Post operatively she developed SMA thrombosis. Unfortunately patient could not be salvaged and she succumbs to death.
A Case Presentation on Seizure Disorder (Epilepsy during Pregnancy)
Authors: Jeyasudha A. , Renjini B. Sree , S. Sanjana ,   Shehataz
Published: April 2020

Seizures during pregnancy complicate <1% of all gestations; however, they are associated with increased adverse maternal and perinatal outcomes (acute and long term). The differential diagnosis of seizures in pregnancy is extensive. Determining the underlying etiology is crucial in the management of these patients. Medical providers caring for pregnant women should be educated about possible etiologies of seizures during pregnancy and the importance of prompt management of these women in a timely fashion. Evaluation and management should be performed in a stepwise fashion and may require a multidisciplinary approach with other specialties such as neurology.

Objective: The objective of this article is to increase awareness and to provide a stepwise approach toward the diagnosis and management of pregnancies complicated by seizures.
A Survey to Assess the Number, Shape and Attachment of the Freni in the Maxillary and Mandibular Arches in South Indian Population
Authors: Nandita Sorte , Bhat Vinaya , Hegde Chethan
Published: April 2020

Frenum is one of the most variable anatomical structures present in the oral cavity which can be defined as a “fibrous band of tissue attached to the bone of the mandible and maxillae, and is 1. present superficial to muscle attachments.”1. In the present study, hundred individuals aged 18 to 40 years were selected randomly. The patients were examined (i) To assess the number, shape and attachment of the freni in the maxillary arch and (ii) To assess the number, shape and attachment of the freni in the mandibular arch in south Indian population. It was concluded that single labial frenum was more common in both the arches, buccal frenum in maxilla were multiple. Whereas, in mandible buccal frenum had single frenal attachment. V-shaped frenal attachment was more in the maxillary and mandibular arches exception being the lingual frenum which showed prevalence pertaining to fan shape.
Terahertz electronics: Application of wave propagation and nonlinear processes
Authors: Aghasi H. , Naghavi S. M. H. , Tavakoli Taba M. , Aseeri M. A. , Cathelin A. , Afshari E.
Published: April 2020

We review the recent advances on the implementation of electronic circuits that operate in the millimeter-wave (30–300 GHz) and terahertz (300–3000 GHz) frequency ranges. The focus of this article is on nonlinear phenomena in electronics. The different implementations of nonlinear circuits for the sake of millimeter-wave and terahertz signal generation are studied in this paper. The challenges of signal generation are examined and the benefits and limitations of different schemes of signal generation are discussed. It is shown that nonlinear devices such as electronic transistors exhibit major advantages enabling realization of low-cost and portable circuits for the emerging applications in these frequency ranges. We also review linear and nonlinear design methodologies employing the properties of electromagnetic waves. The electronic systems designed based on the presented ideas are shown to push the previously unbeatable limits of operation in millimeter-wave and terahertz frequency ranges. A discussion on remaining challenges and future directions concludes the paper.
Solution enthalpy calculation for impurity in liquid metal by first-principles calculations: A benchmark test for oxygen impurity in liquid sodium
Authors: Gil Junhyoung , Oda Takuji
Published: April 2020

The solution enthalpy of oxygen in liquid Na was calculated as a test case for the computational method to evaluate the solution enthalpy in liquid metal using first-principles calculations. To obtain the necessary thermodynamic quantities at high temperatures, (i) first-principles molecular dynamics for pure and O-including liquid Na systems, (ii) vibration analysis for an O2 molecule, and (iii) phonon-based quasi-harmonic approximation for solid Na and Na2O were conducted. The calculation results were compared with available experimental data to validate the method. Consequently, the O2 solution enthalpy was calculated to be −387.1 kJ/mol at 600 K and −374.0 kJ/mol at 1000 K, comparable to the experimental data of −375.7 kJ/mol at 600 K and −369.3 kJ/mol at 1000 K. The Na2O solution enthalpy was calculated to be 28.6 kJ/mol at 600 K and 38.2 kJ/mol at 1000 K, while the experimental data gave a temperature-independent value of 46.9 kJ/mol. The possible causes of errors in the calculations were discussed. This work shows that computational calculations can contribute to establishing a fundamental database on the solubility of impurities in liquid metals.
High-temperature quantum anomalous Hall insulator in two-dimensional Bi2ON
Authors: Liang Yan , Ma Yandong , Zhao Pei , Wang Hao , Huang Baibiao , Dai Ying
Published: April 2020

Chiral edge states in quantum anomalous Hall (QAH) insulators can conduct dissipationless charge current, which has attracted extensive attention recently. One major obstacle for realistic applications is the lack of suitable room-temperature QAH systems, especially with both robust ferromagnetic (FM) order and large gaps. Here, based on first-principles, we report a long-sought high temperature QAH system in the Bi (111) film asymmetrically functionalized with nitrogen and oxygen. The FM Curie temperature is as high as 420 K, while the nontrivial bulk gap reaches up to 454 meV, rendering that the QAH effect can readily be observed at room temperature or even high temperature. Further analysis of the gapless chiral edge states, Chern number (C = 1), and quantized QAH conductivity offers solid evidence of its nontrivial feature. Our work provides an opportunity for realizing the high-temperature QAH effect and fabricating energy-efficient spintronics operating at room temperature.
Effect of passivation on piezoelectricity of ZnO
nanowire
Authors: Chen Gong , Wang Pan-shuo
Published: April 2020

Surface passivation is one valuable approach to tune the properties of nanomaterials. The piezoelectric properties of hexagonal [001] ZnO nanowires with four kinds of surface passivations were investigated using the first-principles calculations. It is found that in the 50% H(O) and 50% Cl(Zn), 50% H(O) and 50% F(Zn) passivations, the volume and surface effects both enhance the piezoelectric coefficient. This differs from the unpassivated cases where the surface effect was the sole source of piezoelectric enhancement. In the 100% H, 100% Cl passivations, the piezoelectric enhancement is not possible since the surface effect is screened by surface charge with weak polarization. The study reveals that the competition between the volume effect and surface effect influences the identification of the diameter-dependence phenomenon of piezoelectric coefficients for ZnO nanowires in experiments. Moreover, the results suggest that one effective means of improving piezoelectricity of ZnO nanowires is shrinking axial lattice or increasing surface polarization through passivation.
Population change of OH and H2O in water vapor glow discharge measured using concentration modulation spectroscopy
Authors: Li Bao , Wang Li , Fang Bo , Zhao Wei-xiong , Deng Lun-hua , Xu Huai-liang
Published: April 2020

A distributed feedback laser with a wavelength of 2.8 µm was used to measure the species produced by water vapor glow discharge. Only the absorption spectra of OH radicals and transient H2O molecules were observed using concentration modulation (CM) spectroscopy. The intensities and orientations of the absorption peaks change with the demodulation phase, but the direction of one absorption peak of H2O is always opposite to the other peaks. The different spectral orientations of OH and H2O reflect the increase or the decrease of the number of particles in the energy levels. If more transient species can be detected in the discharge process, the dynamics of excitation, ionization, and decomposition of H2O can be better studied. This study shows that the demodulation phase relationship of CM spectrum can be used to study the population change of molecular energy levels.
Reaction mechanism and product branching ratios of
OH+C2H3F reaction: A theoretical study
Authors: Chin Chih-Hao , Zhu Tong , Zhang John Zeng-Hui
Published: April 2020

Ab initio CCSD(T)/CBS//B3LYP/6-311G(d,p) calculations of the potential energy surface for possible dissociation channels of HOC2H3F, as well as Rice-Ramsperger-Kassel-Marcus (RRKM) calculations of rate constants, were carried out, in order to predict statistical product branching ratios in dissociation of HOC2H3F at various internal energies. The most favorable reaction pathway leading to the major CH2CHO+HF products is as the following: OH+C2H3F→i2→TS14→i6→TS9→i3→TS3→CH2CHO+HF, where the ratedetermining step is HF elimination from the CO bridging position via TS11, lying above the reactants by 3.8 kcal/mol. The CH2O+CH2F products can be formed by F atom migration from Cβ to Cα position via TS14, then H migration from O to Cα position via TS16, and C–C breaking to form the products via TS5, which is 1.8 kcal/mol lower in energy than the reactants, and 4.0 kcal/mol lower than TS11.
The levitation of a sphere by two parallel turbulent jets
Authors: Barois Thomas , Ricard Guillaume , Champain Victor , Gey Lucas , Kellay Hamid
Published: April 2020

Two vertical turbulent round jets are used to levitate a spherical particle. First, a symmetric configuration is investigated with the two jets of equal flow rates. A structure reminiscent of a pitchfork bifurcation is reported and characterized between a double trap configuration for low flow rates and a single trap regime at higher flow rates. A second configuration is then studied with the flow rates that differ between the left and right jets. In this case, a preferential transition toward the jet of a higher flow rate is reported and quantified. A model is presented predicting the force field for the symmetric and asymmetric configurations. The model is compared to the force field measurements realized with a particle on a flexible cantilever. Finally, a particle dynamics simulation is proposed to analyze in more detail the transition for the levitation in the symmetric and asymmetric configurations.
Quality factor boosting of bulk acoustic wave resonators based on a two dimensional array of high-Q resonant tanks
Authors: Pillai Gayathri , Li Sheng-Shian
Published: April 2020

An innovative resonance excitation methodology of a two-dimensional array of uniformly patterned structure into extremely high-quality factor (Q) mode using engineered frequency-matched thin piezoelectric film on substrate (TPoS) transducer is demonstrated in this Letter. The passive Q-enhancement can be attained lithographically without adding to the power requirement of the system. A 500 nm thick piezoelectric material facilitates the inter-electrical-mechanical domain coupling, and the displacement generated at the transducer periphery drives the patterned 10 μm thick single crystal silicon plate into various resonant modes. Using this topology, unexplored modes can be generated as well by the forced vibration feature of the interacting resonant tanks. Utilizing a multiport port excitation scheme, multiple modes are explored, while the primary focus is maintained on the Lamé mode of the array. In vacuum for an operational frequency of 58.56 MHz, an exceptionally high-quality factor of 58 276 is attained with a motional resistance of 1250 Ω and this is the record-high figure of merit (f × Q = 3.4 × 1012) attained for aluminum nitride-based TPoS based resonators. This successful demonstration of the energy coupling scheme paves a path for the study of existing and investigation of unexplored high-Q modes spanning over a wide range of frequency, making these devices a potential candidate for radio frequency front-end applications. The CMOS compatibility of aluminum nitride makes it an attractive solution for achieving low phase noise monolithically integrated CMOS–microelectromechanical systems oscillators.
Saline water intake effects performance, digestibility, nitrogen and water balance of feedlot lambs
Authors: Reneu Rosas de Albuquerque Ítalo , Garcia Leal de Araujo Gherman , Vinhas Voltolini Tadeu , Helder de Andrade Moura José , Germano Costa Roberto , Costa Gois Glayciane , Pinheiro Costa Samir Augusto , Sena Campos Fleming , Ávila Queiroz Mário Adriano , de Souza Sá Santos Nilmara Mércia
Published: April 2020

Context
Water availability is often a limiting factor for herds in the arid and semiarid regions worldwide.

Aim
The present study aimed to evaluate the productive performance and nutritional status of Santa Inês sheep receiving water containing different levels of salinity.

Methods
Thirty-two intact Santa Inês lambs, with an average bodyweight of 21.76 ± 1.25 kg, were distributed in a completely randomised design with four treatments (concentrations of total dissolved solids (TDS) in the drinking water: 640, 3200, 5760 and 8320 mg/L TDS), and eight animals per treatment. Intake, apparent nutrient digestibility, water balance, nitrogen balance, and performance of animals were evaluated.

Key results
Concentrations of TDS in water promoted an increasing linear effect for water intake offered via drinking trough (P = 0.01), total water intake (P = 0.02), total urine excretion (P = 0.02), total water excretion via urine (P = 0.01), water excretion via faeces (P = 0.04), total water excretion (P = 0.01), absorbed water (P = 0.02), total nitrogen intake (P = 0.04), and water intake to total weight gain ratio (P = 0.01). No effect of increasing TDS concentration was observed for intake of dry matter and nutritional fractions, nutrient digestibility, water intake via food, total faeces excretion, water balance, nitrogen excretion via faeces, nitrogen excretion via urine, total nitrogen excretion, absorbed nitrogen and nitrogen balance (P > 0.05). No difference was observed in the performance of Santa Inês sheep consuming water with TDS concentration up to 8320 mg/L, which presented a daily mean weight gain of 0.105 kg/day.

Conclusions
Water with a concentration of TDS of up to 8320 mg/L can be used as drinking water for Santa Inês sheep.

Implications
Therefore, the water from wells, which is usually saline, may be an alternative to supplying small ruminants.
GP services in Australia: presentation profiles during usual practice hours and after-hours periods
Authors: Baker Jannah , Britt Helena , Harrison Christopher
Published: April 2020

After-hours general practitioner (GP) services can reduce emergency department demand, which is currently increasing in Australia. Understanding GP after-hours care may assist in service planning. From April 2014 to March 2015, 986 GPs recorded 38275 consultations with start and finish times in the Bettering the Evaluation and Care of Health (BEACH) study, a national, cross-sectional, representative study of GP activity. GP and patient characteristics and the content of encounters in usual-hours and after-hours were compared. Significantly more after-hours than usual-hours encounters were with: GPs aged 60+ years; in metropolitan practices; and practices with 10+ GPs. Patients seen after-hours were more often: male; aged 15–64 years; new to practice; and less likely to hold a Commonwealth Concession Card. They were more likely to be prescribed antibiotics and less likely to: have chronic problems managed; be referred; receive psycholeptic or psychoanaleptic prescription; and undergo a procedure. Throat symptoms, fever and injury were more common reasons for encounter, while infections and injury were more frequently managed problems after-hours. The patient mix, GP characteristics, problems managed and management actions in after-hours care differ from those in usual-hours care in Australia. This greater understanding of after-hours care is the first step to informed resource allocation to improve the delivery of after-hours primary care.
Persistence of the broad-toothed rat (Mastacomys fuscus) across Victoria is correlated with climate and elevation
Authors: Shipway S. , Rowe K. M. C. , Rowe K. C.
Published: April 2020

Abstract
ContextThe broad-toothed rat (Mastacomys fuscus; BTR) is distributed throughout south-eastern Australia, but its populations are restricted and dispersed. BTRs prefer cooler, wetter habitats and, as such, future climate change is projected to lead to further range reductions. However, recent changes in its distribution have not been well documented, and there is limited knowledge about the current occupancy and population size of the species in Victoria.
AimsTo evaluate recent historical changes in the distribution of BTRs in Victoria, and to test whether changes in distribution are correlated with climate and elevation.
MethodsWe obtained all documented records of BTRs in the state before 1990 and used field notes and verbal descriptions to geo-reference their historical localities. We then used a repeated sampling design to resurvey all historically occupied sites with a geographic coordinate uncertainty of 4km or less. We tested for the effects of climate and elevation on the persistence of BTRs.
Key resultsWe detected BTRs at 32 of 68 historical sites surveyed. Consistent with climate model predictions, site persistence was more likely to occur at sites of higher elevation and precipitation and less likely to occur at sites with a higher temperature. Minimum temperature of the coldest month was the single best predictor of persistence.
ConclusionsThese results demonstrated a substantial decline in the persistence of BTRs at historical sites across Victoria and provided a benchmark for future monitoring and management efforts.
ImplicationsThe decline of BTRs from historically occupied sites across Victoria is consistent with their listing as endangered in the state, and climate correlations suggest further declines, with projected climate change compounding other threats to the species such as introduced predators, feral herbivores, fire and land use. However, the status of BTRs in Victoria and understanding of the threats to their persistence are based on sparse data, highlighting the critical need for more effective monitoring of the species.
Digital labour at economic margins: African workers and the global information economy
Authors: Anwar Mohammad Amir , Graham Mark
Published: April 2020

The main aim of this briefing is to make visible the invisible and bring light to the role African workers are playing in developing key emergent and everyday digital technologies such as autonomous vehicles, machine learning systems, next-generation search engines and recommendations systems. Once we acknowledge that many contemporary digital technologies rely on a lot of human labour to drive their interfaces, we can begin to piece together what the new global division of labour for digital work looks like and build a greater socio-political response (both at the global and local scale) to make some of these value chains more transparent, ethical and rewarding.
Antigen-responsive CD4+ T cell clones contribute to the HIV-1 latent reservoir
Authors: Mendoza Pilar , Jackson Julia R. , Oliveira Thiago Y. , Gaebler Christian , Ramos Victor , Caskey Marina , Jankovic Mila , Nussenzweig Michel C. , Cohn Lillian B.
Published: April 2020

Antiretroviral therapy suppresses but does not cure HIV-1 infection due to the existence of a long-lived reservoir of latently infected cells. The reservoir has an estimated half-life of 44 mo and is largely composed of clones of infected CD4+ T cells. The long half-life appears to result in part from expansion and contraction of infected CD4+ T cell clones. However, the mechanisms that govern this process are poorly understood. To determine whether the clones might result from and be maintained by exposure to antigen, we measured responses of reservoir cells to a small subset of antigens from viruses that produce chronic or recurrent infections. Despite the limited panel of test antigens, clones of antigen-responsive CD4+ T cells containing defective or intact latent proviruses were found in seven of eight individuals studied. Thus, chronic or repeated exposure to antigen may contribute to the longevity of the HIV-1 reservoir by stimulating the clonal expansion of latently infected CD4+ T cells.
Learning to use Cartesian coordinate systems to solve physics problems: the case of ‘movability’
Authors: Volkwyn Trevor S , Gregorcic Bor , Airey John , Linder Cedric
Published: April 2020

In this paper, we show that introductory physics students may initially conceptualise Cartesian coordinate systems as being fixed in a standard orientation. Giving consideration to the role that experiences of variation play in learning, we also present an example of how this learning challenge can be effectively addressed. Using a fine-grained analytical description, we show how students can quickly come to appreciate coordinate system movability. This was done by engaging students in a conceptual learning task that involved them working with a movable magnetometer with a printed-on set of coordinate axes to determine the direction of a constant field (Earth’s magnetic field).
Factors influencing ion energy distributions in pulsed inductively coupled argon plasmas
Authors: Chen Zhiying , Longo Roberto C , Hummel Michael , Carruth Megan , Blakeney Joel , Ventzek Peter , Ranjan Alok
Published: April 2020

Pulsed plasmas are important for the fabrication of nanoscale features. Source biasing is generally associated with the control of the ion to radical flux ratio; how the ion energy distribution function varies over a pulse period is also important. In this paper, we experimentally investigate the effect of pulse transients (i.e. power on to power off phases) on ion energy distributions during different RF source power duty cycles (99%–20%) in a compact inductively coupled argon plasma with time average RF power of 150 W at a frequency of 13.56 MHz and pressure of 20 mT (2.67 Pa). The ion energy distributions were measured by retarding field energy analyzer. With the decrease of RF power duty cycle, the increase of ion energy and energy spread is observed and ion energy distribution changes from single peaked to bi-modal. The effect of RF power duty cycle on the ion energy transition is discussed. Fluid and test particle simulations are used to illustrate the origin of features in the measured ion energy distributions. Capacitive coupling from the RF induction coils is highlighted as the origin for important features in the ion energy distributions.
Generating two-dimensional quantum gases with high stability*
Authors: Xiao Bo , Wang Xuan-Kai , Zheng Yong-Guang , Yang Yu-Meng , Zhang Wei-Yong , Su Guo-Xian , Li Meng-Da , Jiang Xiao , Yuan Zhen-Sheng
Published: April 2020

Quantum gas microscopy has enabled the study on intriguing properties of ultracold atoms in optical lattices. It provides the cutting-edge technology for manipulating quantum many-body systems. In such experiments, atoms have to be prepared into a two-dimensional (2D) system for being resolved by microscopes with limited depth of focus. Here we report an experiment on slicing a single layer of the atoms trapped in a few layers of pancake-shaped optical traps to create a 2D system. This technique is implemented with a microwave “knife”, i.e., a microwave field with a frequency defined by the resonant condition with the Zeeman-shifted atomic levels related to a gradient magnetic field. It is crucial to keep a stable preparation of the desired layer to create the 2D quantum gas for future experimental applications. To achieve this, the most important point is to provide a gradient magnetic field with low noises and slow drift in combination with a properly optimized microwave pulse. Monitoring the electric current source and the environmental magnetic field, we applied an actively stabilizing circuit and realized a field drift of 0.042(3) mG/hour. This guarantees creating the single layer of atoms with an efficiency of 99.92(3)% while atoms are hardly seen in other layers within 48 hours, satisfying future experimental demands on studying quantum many-body physics.
Switching of plasmonic resonances in multi-gap resonators at terahertz frequencies
Authors: Li Quan , Luo Yuqi , Liu Shanshan , Li Xiuming , Wang Shuang , Chen Tai
Published: April 2020

Switching plasmonic resonance modes in metamaterials have drawn enormous attention in recent years due to its great potential in applications in electromagnetic modulation and sensing. The switching process is essentially dependent on the connection way in the gaps of the metamaterial structure. In this work, we experimentally investigate the resonance switching effect in a multi-gap metamaterial structure at terahertz frequencies. It is found that a new inductor-capacitor circuit (LC) resonance would generate if the center gaps are totally connected. By decomposing the types of the connection in the center gaps, it is found that under horizontally polarized incidences, such switching effect is attributed to the horizontal connection (HC), while the vertical connection (VC) cannot bring any change in the transmission. This characteristic is further theoretically generalized to an active modulator by replacing the metallic HC to vanadium dioxide (VO2) HC, where the dynamic switching effect is observed. The detail study in the resonance switching effect may broaden the avenues toward the control of terahertz waves and the development of modulators and sensors in the terahertz band.
A study on influence of superparamagnetic iron oxide nanoparticles (SPIONs) on green gram (Vigna radiata L.) and earthworm (Eudrilus eugeniae L.)
Authors: Samrot Antony V , C SaiPriya , Selvarani A Jenifer , Subbu R Venket , Cypriyana P J Jane , Y Lavanya , Afreen R Shehanaz , P Soundarya , Priyanka R B Sherly , P Sangeetha , Varghese Reji Joseph , Kumar S Suresh
Published: April 2020

Nanoparticles usage are now emerging as hazardous nanopollutants due to inappropriate usage and improper disposal. Superparamagnetic Iron Oxide Nanoparticles (SPIONs) is a widely used nanoparticle with various applications. In this study, SPIONs was evaluated for its impact against Vigna radiata and Eudrilus eugeniae. SPIONs were synthesized by chemical co-precipitation method in presence of cobalt chloride. The produced SPIONs was characterized using UV-Visible Spectroscopy, SEM (Scanning electron microscopy), EDX (Energy dispersive X-ray spectroscopy), XRD (X-ray diffraction), TEM (Transmission electron microscopy), AFM (Atomic force microscopy), XPS (X-ray photoelectron spectroscopy) and Zeta potential. The synthesized SPIONs were crystalline and monodispersed with size ranging between 15 nm and 20 nm. The seedlings of SPIONs treated Vigna radiata were found to have reduced root and shoot growth. The bioaccumulation of iron oxide in the treated plants was confirmed by ICP-OES (Inductively coupled plasma - optical emission spectrometry) analysis and Prussian blue staining. Cellular destruction and reduced reproduction rate were found in SPIONs exposed Eudrilus eugeniae and ICP-OES analysis of earthworm samples affirmed the bioaccumulation of SPIONs.
A first-principles study on the site occupancy behavior of transition metals in L12-Al3Li phase
Authors: Gao Ming , Deng Yonghe , Wen Dadong , Zhao Heping
Published: April 2020

The main strengthening mechanism in Al-Li alloys is generally achieved by the existence of a high volume fraction of the L12-Al3Li precipitation from Al matrix. In this work, we do density functional theory (DFT) total energy calculations on the site occupancy behaviour of transition metals in L12-Al3Li compound. The ground state properties of L12-Al3Li, fcc-Al, and bcc-Li are determined and compared to the available literature data. The formation energies of intrinsic point defects in L12-Al3Li phase as well as Al3LiX alloy formation energy are calculated and identified. We show that the Li antisite is preferential to from in the L12-Al3Li phase. Finally, the site occupancy behaviour of transition metals in L12-Al3Li as well as the solute atomic volume effect on the solute site preference and lattice expansion of the L12-Al3Li have been studied, the later results can be used for an indirect estimation of the site substitution behaviour of the alloying elements in L12-Al3Li phase.
Diversifying temporal responses of magnetoactive elastomers
Authors: Tan Kai , Wen Xin , Gong Xun , Deng Qian , Shen Shengping
Published: April 2020

Magnetoactive elastomers(MAEs) are able to deform significantly in response to the application of magnetic fields. Usually, a magnetic field which is harmonic in time usually results in a harmonic mechanical response of the MAEs. To render MAEs with the ability of responding or deforming diversely or anharmonically in time, in this work, we propose a hybrid MAE which is based on a rubber matrix embedded with both soft iron particles and hard NdFeB-alloy particles. Firstly, based on the principle of minimum free energy, we establish a theoretical model to study magnetomechanical behaviors of the proposed hybrid MAEs. Then, through both theoretical and experimental studies, we show that the response of a hybrid MAE sample to the applied magnetic field is usually complex, i.e. the deformation induced by a harmonic magnetic field in time is anharmonic. At last, the effect of two main factors, the state of magnetization and the amplitude of the applied magnetic field, is studied both experimentally and theoretically. This work provides a new idea of diversifying the temporal response of MAEs to the application of harmonic magnetic fields (harmonic in time). The hybrid MAEs may serve as a complement to the recently proposed 3D-printed hard MAEs which are able to deform inhomogeneously in space in response to a uniform magnetic field.
Study on aging strengthening and nano precipitates of Cu–Ni–Mn–Fe alloy
Authors: Zou Juntao , Shi Lin , Shi Hao , Feng Qiaoli , Liang Shuhua
Published: April 2020

This paper presents a systematic study of the precipitation strengthening mechanism in polybasic Cu–Ni–Mn–Fe alloy. The effect of aging treatment on the microstructure, morphologies and phase transition of the Cu–Ni–Mn–Fe alloy were analyzed and discussed using scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD) and differential scanning calorimeter (DSC), respectively. The θ-MnNi precipitates with a size of 50–100 nm, mainly formed during aging, were considered as the source of the aging strengthening. In addition, there is a semi-coherent between the plane (111) of the θ-MnNi precipitates and the plane (200) of the α-Cu matrix. The density of θ-MnNi precipitates increases with the increase of the aging time. The hardness, yield strength and ultimate tensile strength of the aged alloy increase from 127 to 366HB, 217 to 788 MPa, and 433 to 842 MPa, respectively, which is attributed to precipitation strengthening.
Reference dose determination in 60Co and high-energy radiotherapy photon beams by using Farmer-type cylindrical ionization chambers – an experimental investigation
Authors: Swanpalmer John
Published: April 2020

Ionization chamber dosimetry is predominantly used for determination of the absorbed dose to water in 60Co and high-energy radiotherapy photon beams. The most widespread ionization chambers employed for absolute or reference dose determinations in reference conditions are the Farmer-type cylindrical ionization chambers. The Farmer-type ionization chambers have a variety of constructions and materials and their responses vary in the radiation beam. Clinical accelerators, in addition to conventional photon beams with flattening-filter, can also deliver flattening-filter-free (FFF) photon beams. The responses of five different Farmer-type cylindrical ionization chambers were experimentally examined with reference to absorbed dose determination in reference conditions when using the International Atomic Energy Agency (IAEA) - American Association of Physicists in Medicine (AAPM) Technical Reports Series no. 483 (TRS-483) and the IAEA TRS-398 dosimetry protocol in the present investigation. The irradiations were performed using 60Co and megavoltage photon beams with 6 MV, 15 MV, 6 MV FFF and 10 MV FFF nominal photon energies. The chamber calibrations were performed at different Secondary Standard Dosimetry Laboratories and are traceable to primary standards at different Primary Standard Dosimetry Laboratories. The chambers were also cross-calibrated at our laboratory using 60Co γ-beam. The variation found in the data regarding the reference dose determination using the various Farmer-type chambers in the photon beams employed was about 1% at maximum. Thus, the selection of the ionization chamber in reference dose determinations may affect the outcomes. The differences in the absorbed dose values were similar in the conventional as well as in the FFF photon beams. For the FFF photon beams the absorbed dose computations were performed using the IAEA-AAPM TRS-483 dosimetry protocol. Two of the ionization chambers used had identical construction but different central electrodes, i.e. graphite versus aluminium. The results obtained using these two chambers show that, in the photon beams examined, the employed correction for the central electrode (p

cel
) regarding these two chambers is associated with an inaccuracy which is larger than the calculated uncertainty for this correction. The outcomes found in the present experimental investigation using the various ionization chambers also indicate possible inaccuracy in the employed beam quality correction factors (k

Q
) and imply the need for a revision of these factors.
MOVPE growth of GaN on patterned 6-inch Si wafer
Authors: Kim Iurii , Holmi Joonas , Raju Ramesh , Haapalinna Atte , Suihkonen Sami
Published: April 2020

We demonstrate that thicker layers can be achieved in gallium nitride (GaN) epitaxy by using a patterned silicon (Si) substrate compared to a planar Si substrate. GaN films were grown by metalorganic vapour-phase epitaxy on 6-inch Si (111) substrates patterned with arrays of squares with various corner shapes, height and lateral dimensions. Stress spatial distributions in the GaN pattern units were mapped out using confocal Raman spectroscopy. It was found that the corner shapes have an effect on the uniformity of the stress distribution. Patterns with round corners were found to have more uniform stress distribution than those with sharp corners. The largest crack-free square size for a 1.5 μm thick GaN film is 500 × 500 μm2.
Sleeping in Church: Preaching, Boredom, and the Struggle for Attention in Medieval and Early Modern Europe
Authors: Jütte Daniel
Published: April 2020

The word “boredom” was not used in English before the eighteenth century. Does this mean that pre-eighteenth-century people did not experience boredom? Or did their experience of boredom differ from ours? This article approaches these questions by exploring the history of people falling asleep in church, and asking whether boredom played a role in their slumber. Across the confessional spectrum in premodern Europe, religious somnolence was depicted as a common and grave problem. The preoccupation with this problem went hand in hand with longstanding ecclesiastic concerns about deficient attention among the flock. Probing medieval and early modern controversies about somnolence and boredom offers insight on two levels: First, it helps to correct the problematic presentism that identifies boredom as a quintessentially modern condition. Second, exploring the long history of boredom adds nuance to our understanding of premodern culture and mentalities, revealing—in the case of religious audiences—a struggle for attention that we would not expect to find in a world in which religion reigned supreme. The article also touches on other social and institutional contexts (such as court life) in which boredom was both endogenous and endemic.
Only One Way To Swim? The Offence And The Life Course In Accounts Of Adaptation To Life Imprisonment
Authors: Jarman Ben
Published: April 2020

Recent studies of long-term imprisonment describe a largely invariant pattern of prisoner adaptation. Using data from a qualitative study of men serving life sentences in England, I argue that adaptation may in fact vary more than these studies imply both because of the prisoner’s age when sentenced and because of the circumstances of particular offences. Participants’ engagement with the prison’s rehabilitative ‘offer’ depended on how the sentence affected their life course and what they understood to be the moral ramifications of the offence. These findings refine understanding of adaptation and suggest that a renewed focus on moral reflexivity may bear fruit in future prison research.
Remaking the #Syllabus: Crowdsourcing Resistance Praxis as Critical Public Pedagogy
Authors: Clark Meredith D
Published: April 2020

Between 2014 and 2017, the creation of hashtag syllabi—bricolage iterations of reading lists created by or circulated among educators on Twitter—emerged as a direct response for teaching about three highly publicized incidents of racial violence in the United States. Educators used hashtags as a means of sharing resources with their networks to provide non-normative literatures from marginalized scholars for teaching to transgress in the wake of Mike Brown’s slaying in Ferguson, Missouri; the massacre of nine congregants at Emmanuel AME Church in Charleston, South Carolina; and the fatal car attack on anti-fascist protestors in Charlottesville, Virginia. Acting on Chakravartty et al.’s provocation to center scholars of color in course syllabi as a pedagogical strategy to disrupt the reification of white supremacy in communication and media studies, I consider the creation of three hashtag syllabi related to these events as a form of critical resistance praxis in the emerging framework of digital intersectionality theory. I present a brief textual analysis of the aforementioned syllabi, triangulated with data from online conversations linked to them via their hashtags and derivative works produced by their creators and users to map two social media assisted strategies for doing critical public pedagogy.
Evolutionary selection against short nucleotide sequences in viruses and their related hosts
Authors: Zarai Yoram , Zafrir Zohar , Siridechadilok Bunpote , Suphatrakul Amporn , Roopin Modi , Julander Justin , Tuller Tamir
Published: April 2020

Viruses are under constant evolutionary pressure to effectively interact with the host intracellular factors, while evading its immune system. Understanding how viruses co-evolve with their hosts is a fundamental topic in molecular evolution and may also aid in developing novel viral based applications such as vaccines, oncologic therapies, and anti-bacterial treatments. Here, based on a novel statistical framework and a large-scale genomic analysis of 2,625 viruses from all classes infecting 439 host organisms from all kingdoms of life, we identify short nucleotide sequences that are under-represented in the coding regions of viruses and their hosts. These sequences cannot be explained by the coding regions’ amino acid content, codon, and dinucleotide frequencies. We specifically show that short homooligonucleotide and palindromic sequences tend to be under-represented in many viruses probably due to their effect on gene expression regulation and the interaction with the host immune system. In addition, we show that more sequences tend to be under-represented in dsDNA viruses than in other viral groups. Finally, we demonstrate, based on in vitro and in vivo experiments, how under-represented sequences can be used to attenuated Zika virus strains.
Left ventricular trabeculation and major adverse cardiovascular events: the Copenhagen General Population Study
Authors: Sigvardsen Per E , Fuchs Andreas , Kühl Jørgen T , Afzal Shoaib , Køber Lars , Nordestgaard Børge G , Kofoed Klaus F
Published: April 2020

Aims 

Prominent left ventricular trabeculations is a phenotypic trait observed in cardiovascular diseases. In the general population, the extent of left ventricular trabeculations is highly variable, yet it is unknown whether increased trabeculation is associated with adverse outcome.

Methods and results 

Left ventricular trabeculated mass (g/m2) was measured with contrast-enhanced cardiac computed tomography in 10 097 individuals from the Copenhagen General Population Study. The primary endpoint was a composite of major adverse cardiovascular events and defined as death, heart failure, myocardial infarction, or stroke. The secondary endpoints were the individual components of the primary endpoint. Cox regression models were adjusted for clinical parameters, medical history, electrocardiographic parameters, and cardiac chamber sizes. The mean trabeculated mass was 19.1 g/m2 (standard deviation 4.9 g/m2). During a median follow-up of 4.0 years (interquartile range 1.5–6.7), 710 major adverse cardiovascular events occurred in 619 individuals. Individuals with a left ventricular trabeculated mass in the highest quartile had a hazard ratio for major adverse cardiovascular events of 1.64 [95% confidence interval (CI) 1.30–2.08; P < 0.001] compared to those in the lowest quartile. Corresponding hazard ratios were 2.08 (95% CI 1.38–3.14; P < 0.001) for death, 2.63 (95% CI 1.61–4.31; P < 0.001) for heart failure, 1.08 (95% CI 0.56–2.08; P = 0.82) for myocardial infarction, and 1.07 (95% CI 0.72–1.57; P = 0.74) for stroke.

Conclusion 

Increased left ventricular trabeculation is independently associated with an increased rate of major adverse cardiovascular events in the general population.
Sex differences in shigellosis incidence rates: analysis of national data from nine countries using meta-analytic method
Authors: Peer Victoria , Schwartz Naama , Green Manfred S
Published: April 2020

Background

Sex differences in the incidence of infectious diseases can provide insight to the biological mechanism of infection, disease susceptibility, severity and vaccine development. The consistency of age-specific sex differences in the incidence rates (IRs) of shigellosis is unclear.

Methods

National data on cases of shigellosis by sex, age group and calendar year were obtained from nine countries, for a period of 6–25 years. The male to female incidence rate ratios (RR) were calculated by country, years and age group. For each age group, meta-analytic methods were used for computing pooled incidence RRs by country and years. Meta-regression was performed to estimate the contribution of age, country and time period to the differences in the male : female RRs.

Results

In the age groups <1, 1–4, 5–9 and 10–14, there were excess IRs in males. The pooled incidence RRs (with 95% CI) were 1.21 (1.14–1.28), 1.17 (1.12–1.22), 1.04 (1.00–1.09) and 1.09 (1.01–1.18), respectively. In young adults, there was excess IR in females with RR = 0.80 (0.72–0.9). In middle aged and older adults, there was a slight excess in males with RR = 1.01 (0.89–1.15) and RR = 1.18 (1.09–1.28), respectively. In the meta-regression, age was the only variable that significantly contributed to the variation in the RRs.

Conclusions

The higher IRs in male infants and young children does not appear to be related to behavioral factors and genetic and hormonal factors could be important. In the older age groups, the higher rates in adult females may be due to behavioral factors.