bluuebunny/crossref_metadata_2025 huggingface dataset:
Adherence to Teriparatide Treatment and Risk of Fracture: A Systematic Review and Meta-Analysis
Authors: Chen Qing , Guo Man , Ma Xiumei , Pu Yueli , Long Yang , Xu Yong
Published: December 2019

To conduct a retrospective systematic review and meta-analysis of studies investigating the fracture risk among adherence versus non-adherence patients to treatment for osteoporosis. Cohort studies involving adherence to specifically Teriparatide treatment and the risk of fracture, published from inception to June 10 2019, were identified through PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, and Scopus database of Systematic Reviews. Five eligible cohort studies were included for analysis. Overall, adherence, compared with nonadherence, had a significant 28% reduction in the risk of all fractures, an 49% reduction in the risk of hip fracture and an 26% reduction in the risk of non-vertebral fracture. Subgroup analyses showed that treatment compliant North American patients had a lower incidence of fracture than treatment compliant Asian patients. The effect size associated with adherence showed no difference with non-adherence when the analysis was limited to a small sample size (<10 000 patients). The findings of this retrospective review indicate that high compliance of Teriparatide treatment result in a decreased risk of fracture, particularly in North American treatment adherence, compared with Asian treatment adherence. Improvement of treatment adherence in patients with osteoporosis should be considered through various means in clinical practice.
Circadian Biology and Its Importance to Intensive Care Unit Care and Outcomes
Authors: Gao Catherine A. , Knauert Melissa P.
Published: December 2019

Circadian rhythms are an integral part of life on earth. Circadian rhythms play a fundamental role in homeostasis as they ensure coordination between the environment and an organism's behavior and physiology. This coordination is called entrainment. Entrainment depends on environmental cues known as zeitgebers. Human zeitgebers include light (primary zeitgeber), sleep, eating, exercise, and activity. Circadian rhythms are disrupted in critically-ill patients due to both critical illness and current intensive care unit (ICU) practices. Disruptions in circadian rhythms are tightly linked with ICU sleep disruption. Together these entities potentiate numerous adverse outcomes including delirium, metabolic derangements, cardiovascular instability, and immune compromise. Herein, we will highlight potential areas for care improvement via chronobundles. We suggest bright light during the day, maintaining darkness, and protecting sleep at night, intermittent rather than continuous feeds, and activity via mobilization during the day. Optimizing circadian rhythms is a low-risk intervention that is underutilized in current ICU practice. This optimization could be a powerful tool in helping to improve outcomes in the critically-ill patient.
Efficacy of Neuroprotective Drugs in Acute Ischemic Stroke: Is It Helpful?
Authors: Mehta Anish , Mahale Rohan , Buddaraju Kiran , Javali Mahendra , Acharya Purushottam , Srinivasa Rangasetty
Published: December 2019

Background Out of several neuroprotective drugs (NPDs) studied in animals and humans, four NPDs (citicoline, edaravone, cerebrolysin, and minocycline) have been found to have beneficial effects in acute ischemic stroke (AIS).

Objective The purpose is to evaluate the efficacy of citicoline, edaravone, minocycline, and cerebrolysin compared with placebo in patients with middle cerebral artery (MCA) territory AIS.

Materials and Methods This was a prospective, single center, single-blinded, and hospital-based study. One hundred patients with MCA territory AIS with 20 patients in each group including control group were included. Barthel index (BI), National Institute of Health Stroke Scale (NIHSS) score, and modified Rankin Scale score were recorded at admission, at day 11 and after 90 days.

Results The mean NIHSS score was significantly lesser at day 11 and after 90 days in citicoline, edaravone, and cerebrolysin group in comparison with placebo. Similarly, the mean BI score was significantly higher at day 11 and after 90 days in citicoline, edaravone, and cerebrolysin group in comparison with placebo. In minocycline group, there was no significant change in the NIHSS score and BI score at day 11 and after 90 days.

Conclusion There was significant improvement in the functional outcome of patients with AIS involving MCA territory at 90 days receiving citicoline, edaravone, and cerebrolysin. However, minocycline did not offer the same efficacy as compared with other neuroprotective agents.
Long-Term Study about the Incidence of Epilepsy in Male Service Personnel from India: A Retrospective, Cohort Study
Authors: Dhull Pawan , Patnaik S. K. , Somasekharan Manoj , Kumar K. V. S Hari
Published: December 2019

Background The data on the epidemiology of epilepsy are limited for developing countries including India. We estimated the incidence of epilepsy in a cohort of service personnel from India followed for over two decades.

Materials and Methods The data for this epidemiological study were derived from the electronic medical records (EMRs) of the male service personnel. The participants (age < 18 years) were enrolled into active service between 1990 and 2015 in good health. The data pertaining to the diagnosis of epilepsy were derived from the EMR using the prevalent International Classification of Diseases codes. We calculated the incidence rate as per person-years (py) using appropriate statistical methods.

Results Our data included 51,217 participants (median age: 33 years, range: 17–54) with a mean follow-up of 12.5 years, giving a cumulative follow-up duration of 613,925 py. A total of 291 patients developed epilepsy during the study, giving an incidence rate of 0.47 per 1000 py (95% confidence interval: 0.42–0.53). Undifferentiated spondyloarthropathy, central nervous system disorders, and alcohol dependence syndrome were the common comorbid ailments in patients with epilepsy.

Conclusion Our cohort had a comparable incidence rate of epilepsy with other studies from India and abroad.
Magnetomechanical design and power generation of magnetostrictive clad plate cantilever
Authors: Yang Zhenjun , Onodera Ryuichi , Tayama Tsuyoki , Watanabe Masahito , Narita Fumio
Published: December 2019

A class of the magnetostrictive iron-cobalt/nickel clad plate cantilever is prepared in this study. The relevant ability for harvesting vibration energy is systematically investigated in comparison with the single iron-cobalt cantilever. In addition, the effects of the magnitude of bias magnetic field (i.e., external magnetic field) and the magnetization angle on the energy-harvesting performance are considered. The results indicated that the iron-cobalt/nickel clad plate cantilever exhibits far greater power generation compared with that of the single iron-cobalt cantilever. Besides, the iron-cobalt/nickel clad plate cantilever displayed high sensitivity to the magnitude of bias magnetic field and the magnetization angle. In more detail, the output voltage of the iron-cobalt/nickel clad plate cantilever peaks at a point even while the bias magnetic field constantly increases. A theory of dynamic balance can explain this phenomenon. Meanwhile, the resonance frequency of the iron-cobalt/nickel clad plate cantilever is proportional to the bias magnetic field due to the influence of the elastic modulus variation. This work provides insights into the exploration and design, not only of the vibration-energy-harvesting components but also of the sensitive detectors.
Fundamental study of DC and RF breakdown of atmospheric air
Authors: Aponte I. A. , Esser B. , Shaw Z. C. , Dickens James C. , Mankowski John J. , Neuber Andreas A.
Published: December 2019

Radio frequency (RF) breakdown in air at a frequency of particular relevance to ionospheric heating—3.3 MHz, close to the low end of the applicable frequency range—is studied at centimeter-sized gap distances and compared to the literature for small gaps. To establish a reference point, Paschen's early DC breakdown study utilizing two brass spheres of 1 cm radius was replicated following the original procedure and subsequently extended to examine RF breakdown. Various electrode combinations were tested with brass cathodes creating the highest variance in the datasets among DC tests. The greatest variation in RF breakdown arose when either electrode was brass. Gap distances of 1–10 mm were tested for both DC and RF with the slow-rise time (5 mV/μs) RF breakdown occurring at approximately 80% of the DC breakdown value, a value corroborated by Monte Carlo breakdown simulations. Pushing the envelope rise time of the applied RF voltage into the microsecond regime yielded an RF voltage of roughly 20% above the DC breakdown value accompanied by a distinct increase in breakdown amplitude fluctuations. Illuminating the gap electrodes with deep ultraviolet (280 nm and below) minimized the breakdown amplitude fluctuations due to photoemission at the electrodes as expected. Finally, to address the conditions found in real-world geometries with sharp corners or protrusions, RF corona behavior utilizing tungsten needles above a ground plane is measured. The obtained results help us define the operation limits of high-power antennas at 1–10 MHz frequencies.
Resonant THz transmission through asymmetric aperture array with polarization controlled resonant peaks and Q-factors
Authors: Pattanayak Arnab , Rana Goutam , Jain Ravikumar , Bhattacharya Arkabrata , Duttagupta Siddhartha P. , Gandhi Prasanna S. , Achanta Venu Gopal , Prabhu S. S.
Published: December 2019

In this article, we conduct a study on terahertz (THz) transmission through a periodic array of asymmetric apertures to demonstrate polarization controlled dual transmission windows. Specifically, we show that resonance peaks and Q-factors of these two transmitted bands are controllable via switching the incoming THz light from one polarization state to the orthogonal state. We investigate the origin and dispersion of two transmission peaks using a thorough study of numerical simulation. In our study, we show that depending on the polarization state, Q-factor can be changed from 3 to 100. Such a large variation of resonance quality can be utilized for a variety of applications like high resolution sensing and data communication.
Ab initio simulations for expanded gold fluid in metal-nonmetal transition regime
Authors: Liu Dongxiao , Fan Wei , Shan Lianqiang , Tian Chao , Bi Bi , Zhang Feng , Yuan Zongqiang , Wang Weiwu , Liu Hongjie , Yang Lei , Meng Lingbiao , Cao Leifeng , Zhou Weimin , Gu Yuqiu
Published: December 2019

Ab initio simulations based on quantum molecular dynamics have been performed to study the electrical and optical properties of expanded gold fluids from one to a sixth of the normal solid density and with temperatures varying from 5000 to 20 000 K. With decreasing density, the dynamic conductivity evolves from the characteristic of a metal to that of a nonmetal. The DC conductivity is given by fitting the dynamic conductivity using the Drude or Drude-Smith model. According to the shift of the central peak of dynamic conductivity, the change of the slope of DC conductivity with respect to temperature, and the appearance of the disconnected network in the charge density distribution, the metal-nonmetal transition of expanded gold fluids occurs in the vicinity of one-third of the normal solid density. In addition, as the density decreases, the localization of 6s and 5d states is observed in the density of states.
Structural, magnetic and ferroelectric properties of lead free piezoelectric 0.9(0.45Ba0.7Ca0.3TiO3-0.55BaTi0.8Zr0.2O3) and magnetostrictive 0.1(Co0.7Mn0.3Fe1.95Dy0.05O4) magnetoelectric particulate composite
Authors: Keswani Bhavna C. , Patil S. I. , James A. R. , Nath R. C. , Boomishankar R. , Kolekar Y. D. , Ramana C. V.
Published: December 2019

The structural, magnetic, ferroelectric, and magnetoelectric (ME) properties of lead-free ferroelectric phase (0.45)Ba0.7Ca0.3TiO3-(0.55)BaTi0.8Zr0.2O3 (BCZT) and rare earth modified Co-Mn ferrite phase Co0.7Mn0.3Fe1.95Dy0.05O4 (CMFDO) magnetoelectric (ME) composites are reported. X-ray diffraction confirms the presence of a crystal structure corresponding to both the ferroelectric and ferrite phases, which was further confirmed by Raman spectroscopic measurements. Scanning electron micrograph imaging along with the elemental mapping reveals the distribution of CMFDO grains in a BCZT matrix. The variation of dc resistivity with temperature indicates a semiconducting nature of the ME composite. The ME composite shows usual dielectric dispersion behavior with a higher dielectric constant value in the low frequency region compared to the individual ferroic phases, due to the space charge effects. Frequency dependent ac conductivity reveals that the conduction process in the ME composite is due to the small polaron hopping mechanism. Also, the variation of dielectric constant with temperature reveals the presence of two dielectric anomalies corresponding to ferroelectric phase transitions, i.e., from orthorhombic (O) to tetragonal (T) phases (∼298–323 K) and tetragonal (T) to cubic (C) phases (∼400 K). The ME composite exhibits both the ferroelectric [i.e., polarization (P) vs electric field (E)] and ferrimagnetic [i.e., magnetization (M) vs magnetic field (H)] hysteresis loops that confirm its multiferroic nature. The P-E hysteresis loop indicates the significant changes in remanent polarization (ΔPr ∼ 54%) after magnetic poling, confirming the presence of strong magnetoelectric coupling in the ME composite. Further, the strength of the ME coupling calculated was ∼54%, which is remarkable. Thus, the ME composite prepared in the present study may be a suitable candidate for applications in magnetic field sensors and multistate memory devices and may be suitable alternatives for single phase multiferroics.
The application of multiscale joint permutation entropy on multichannel sleep electroencephalography
Authors: Yin Yi , Peng Chung-Kang , Hou Fengzhen , Gao He , Shang Pengjian , Li Qiang , Ma Yan
Published: December 2019

Sleep quantification and automatic scoring of sleep stages via electroencephalogram (EEG) signals has been a challenge for years. It is crucial to investigate the correlation of brain waves by sleep EEG analysis due to the association between rhythmic oscillations of neuronal activity and neocortical synchronization. Multiscale joint permutation entropy (MJPE) had been proven to be capable of measuring the correlation between time series from the view of multiple time scales and thus can be a promising approach to address the challenge. Instead of simulation, we tested the MJPE method on a widely used open dataset of sleep EEG time series from healthy subjects and found that the correlation index obtained by MJPE had the capability of quantifying the brain wave correlations under different sleep stages, reflecting the typical sleep patterns and indicating the weakened correlation with aging. A higher level of correlation was found as the sleep stage advanced. The findings based on the MJPE results were in accordance with previous studies and existing knowledge in sleep medicine. In the second part of the study, we applied MJPE on sleep EEGs from subjects under pathological conditions (sleep apnea and sleep at high altitude). Likewise, the correlation index also properly revealed their sleep architectures, with consistent trends of the correlation through the nights. The effectiveness and practicability of the MJPE method had been verified on sleep EEGs. Therefore, the MJPE method should be encouraged to be widely used for analyzing large-scale sleep EEGs under various pathological conditions to provide insight into the mechanisms of the sleep process and neuron synchronization.
Tetrahedron maps and symmetries of three dimensional integrable discrete equations
Authors: Kassotakis P. , Nieszporski M. , Papageorgiou V. , Tongas A.
Published: December 2019

A relationship between the tetrahedron equation for maps and the consistency property of integrable discrete equations on Z3 is investigated. Our approach is a generalization of a method developed in the context of Yang–Baxter maps, based on the invariants of symmetry groups of the lattice equations. The method is demonstrated by a case–by–case analysis of the octahedron type lattice equations classified recently, leading to some new examples of tetrahedron maps and integrable coupled lattice equations.
Effects of spatially decaying elastic tension on the instability of viscoelastic jets
Authors: Xie Luo , Jia Bo-qi , Cui Xiao , Yang Li-jun , Fu Qing-fei
Published: December 2019

This paper theoretically examines the spatial linear instability of viscoelastic jets subjected to unrelaxed axial stress tension and moving within an inviscid stationary gas medium. Unlike the constant value assumption of previous studies, the effects of spatial decaying of the unrelaxed stress tension are included here. The Oldroyd-B constitutive equation has been adopted to model fluid viscoelasticity. Results indicated that the effects of unrelaxed stress tension were complicated and mainly dependent on stress relaxation time. When stress relaxation time was short, the maximum growth rates along the jet decreased to the constant value of the completely relaxed case; increasing unrelaxed tension slightly decreased the breakup length. When the stress relaxation time increased to exceed the critical value, the maximum growth rates continued to increase along the jet and larger unrelaxed tensions caused longer breakup lengths. This twofold effect can be explained by the competition between the stabilizing effects of the unrelaxed tension itself and the destabilizing effects of the spatial decay. Moreover, the fluid elasticity suppressed instability when the unrelaxed tension was great. Responses to the spatial decaying unrelaxed tension of the axisymmetric and nonaxisymmetric disturbances for high-speed viscoelastic jets were similar to those of the capillary case. Generally, the complex effects of the interplay between fluid elasticity and the spatially decaying unrelaxed tension may qualitatively explain the breakup behaviors of viscoelastic jets in experiments.
Computational investigation of energy transfer and line broadening for Ar* + He collisions
Authors: Pershin Andrey A. , Ghildina Anna R. , Mebel Alex M. , Azyazov Valeriy N. , Mikheyev Paul A. , Heaven Michael C.
Published: December 2019

Potential energy curves for all states arising from the interaction of He with the 3p6, 3p54s, and 3p54p configurations of Ar have been determined using high-level electronic structure calculations. The results have been used to examine collisional energy transfer probabilities and spectral line shape parameters (shifting and broadening rate coefficients). The main focus has been on states and transitions that are of relevance to optically pumped He/Ar* laser systems. The line shape predictions were found to be in good agreement with experimental data, while there is notable disagreement for the energy transfer probabilities. The experimental data are found to be at variance with the predictions of standard two-state curve crossing models for energy transfer.
Autonomic control is a source of dynamical chaos in the cardiovascular system
Authors: Karavaev A. S. , Ishbulatov Yu. M. , Ponomarenko V. I. , Bezruchko B. P. , Kiselev A. R. , Prokhorov M. D.
Published: December 2019

The origin of complex irregular dynamics in a cardiovascular system is still being actively debated. Some hypotheses suggest the crucial role of stochastic modulation of cardiovascular parameters, while others argue for the importance of cardiac pacemakers' chaotic deterministic dynamics. In the present study, we estimate the largest Lyapunov exponent and the correlation dimension for the 4-h experimental interbeat intervals and the chaotic signals generated by the mathematical model of the cardiovascular system. We study the complexity of the mathematical model for such cases as the autonomic blockade, the exclusion of all the stochastic components, and the absence of variability of respiration. The obtained results suggest that the complexity of the heart rate variability is largely due to the chaotic dynamics in the loops of autonomic control of circulation.
Absorption matrix of multi-site systems calculated by a hybrid quantum-classical Liouville equation
Authors: Gong Zhihao , Wu Jianlan
Published: December 2019

The linear absorption spectrum of a multisite system can be written as a weighted accumulation of elements of an absorption matrix. In the framework of the quantum-classical Liouville equation (QCLE), a mean-field approximation is introduced to simplify the calculation of the absorption matrix. The classical bath oscillators are propagated under partially shifted potentials, which reflects an averaged behavior after considering quantum jumps of the system states. For a specified initial condition, the time-dependent shifting possibility of each bath potential is given by the time evolution of site population estimated by the Redfield equation or the noninteracting blip approximation. The two hybrid QCLE approaches are tested in various models, including biased and unbiased two-site models, a subnetwork and the whole monomer of Fenna-Matthews-Olson, and harmonic and anharmonic baths. With numerically excellent results, the numerical studies show reliability and flexibility of the hybrid QCLE in calculating the absorption matrix and spectrum.
Method of controlling flow around tandem cylinders can reduce damage
Authors: Mandel Savannah
Published: December 2019

Using a suctioning and blowing technique, scientists discovered how to minimize damage done to tandem cylinders by vortex shedding and vibration.
Designing particles to assemble into chosen structures
Authors: Mandel Savannah
Published: December 2019

Scientists program “patchy” particles to assemble like puzzle pieces into complex crystal forms.
Desirable effects of dietary 4-O-methyl-glucuronoarabinoxylan from the Echinacea plant on growth performance, thigh meat quality and development of small intestine in female Partridge-Shank broilers
Authors: Ren Qing-Chang , Xuan Jing-Jing , Che Chuan-Yan , Yan Xin-Chao , Hu Zhong-Ze
Published: December 2019

In this trial we aimed to assess the effects of dietary supplementation of 4-O-methyl-glucuronoarabinoxylan (4OMG) on growth performance, thigh meat quality and small intestine development of female Partridge-Shank broilers. A total of 240 1-day-old female Partridge-Shank broilers were randomly distributed to four groups with three replicates of 20 within each group. Groups received either 0, 15, 20 or 25 g 4OMG/kg DM of diet. During the whole experiment of 60 days, broilers had ad libitum access to water and feed. At pen level, feed intake was recorded daily and broilers were weighed at the start and end of the experiment. For each group, three pens with a total of 20 broilers were randomly selected to determine the thigh meat quality and the small intestine development of broilers. Broilers fed diets with higher 4OMG had greater final liveweight (P = 0.004), daily bodyweight gain (P = 0.004) and gain-to-feed ratio (P < 0.001), muscle pH values (P = 0.031) and redness (P = 0.001), duodenal weight index (P = 0.042), jejunal (P = 0.043) and ileal length (P = 0.049), duodenal (P < 0.001) and ileal villus height (P = 0.008), but lower percentage of dead birds (P < 0.001), drip loss (P = 0.042) and shear force value (P = 0.043) of the thigh muscles. These results indicate that increasing dietary supplementation of 4OMG may improve growth performance and meat quality of female Partridge-Shank broilers through better development of small intestine.
Destabilizing the autoinhibitory conformation of Zap70 induces up-regulation of inhibitory receptors and T cell unresponsiveness
Authors: Hsu Lih-Yun , Cheng Debra A. , Chen Yiling , Liang Hong-Erh , Weiss Arthur
Published: December 2019

Zap70 plays a critical role in normal T cell development and T cell function. However, little is known about how perturbation of allosteric autoinhibitory mechanisms in Zap70 impacts T cell biology. Here, we analyze mice with a hypermorphic Zap70 mutation, W131A, which destabilizes the autoinhibitory conformation of Zap70, rendering the kinase in a semiactive state. W131A mutant mice with wild-type T cell receptor (TCR) repertoires exhibited relatively normal T cell development. However, crossing the W131A mutant mice to OTII TCR transgenic mice resulted in increased negative selection of OTII+ thymocytes and in increased thymic and peripheral T regulatory cells. Strikingly, increased basal TCR signaling was associated with a marked increase in inhibitory receptor expression and with T cells that were relatively refractory to TCR stimulation. PD-1 inhibitory receptor blockade partially reversed T cell unresponsiveness. Collectively, disruption of normal Zap70 autoinhibition engaged negative feedback mechanisms by which negative selection and inhibitory receptors restrain TCR signaling to enforce both central and peripheral tolerance.
Direct observation and simultaneous use of linear and quadratic electro-optical effects
Authors: Steglich Patrick , Mai Christian , Villringer Claus , Mai Andreas
Published: December 2019

We report on the direct observation and simultaneous use of the linear and quadratic electro-optical effect and propose a method by which higher-order susceptibilities of electro-optical materials can be determined. The evaluation is based on the separation of the second- and third-order susceptibilities and the experimental technique uses a slot waveguide ring resonator fabricated in integrated photonic circuit technology, which is embedded by a guest-host polymer system consisting of the azobenzene dye Disperse Red 1 in a poly(methyl methacrylate) matrix as an active electro-optical material. The contribution of both effects on the electro-optical response under the influence of static and time-varying electrical fields is investigated. We show that the quadratic electro-optical effect has a significant influence on the overall electro-optical response even with acentric molecular orientated molecules. Our findings have important implications for developing electro-optical devices based on polymer-filled slot waveguides and give rise to advanced photonic circuits.
First-principles high pressure structure searching, longitudinal-transverse mode coupling and absence of simple cubic phase in sulfur
Authors: Whaley-Baldwin Jack , Needs Richard
Published: December 2019

We use first-principles density functional theory to conduct an extensive structure search using the AIRSS package for elemental sulfur in the range 50–550 GPa. We then obtain the low-temperature phase diagram of sulfur in the same pressure range, including vibrational effects through the harmonic approximation. We do not find any structures lower in energy than those already reported in experiment, although the phase diagram below 100 GPa is found to be crowded with structures separated by only a few meV. We report the transition sequence

I

4

1

/

acd
→
P

1

¯

→

ICM

→

C
2

/

m
→
R

3

¯

m
→

I
m

3

¯

m

and obtain accurate pressures for each transition, although we find the second-order

C
2

/

m
→
R

3

¯

m

transition particularly difficult to define. Contrary to previous first-principles works (Pavel et al; Rudin and Liu 1999 Phys. Rev. Lett.
83 3049–52), we do not reproduce a trigonal

→

simple cubic transition at either the static lattice or harmonic level. We also undertake a detailed analysis of the incommensurately modulated (ICM) phase of sulfur phase using a commensurate approximant found in the structure search. We find that the modulation amplitude is zero above 96 GPa; some 40 GPa below the experimentally reported transition to the unmodulated phase. We find that the body-centred atoms in the relaxed ICM approximant are, in addition to the dominant transverse modulation (which is a frozen-in optical phonon mode), slightly displaced longitudinally in the b-direction. We subsequently discover that this (small) longitudinal modulation is coupled to the transverse mode, and hence report previously unnoticed weak-mode coupling between transverse and longitudinal optical phonons in the ICM phase.
Evidence for Intra-Unit Cell Magnetism in Superconducting Cuprates: a Technical Assessment
Authors: Bourges Philippe , Bounoua Dalila , Jeong Jaehong , Mangin-Thro Lucile , Sidis Yvan
Published: December 2019

Intra unit cell (IUC) magnetic order observed by polarized neutron diffraction (PND) is one of the hallmarks of the pseudogap state of high-temperature copper oxide superconductors. This experimental observation, usually interpreted as a result of loop currents, has been recently challenged based on lower statistics data. We here address the crucial issue of polarization inhomogeneities in the neutron beams showing that the original data had a much better reproducibilty. Within these technical limitations, we here propose a self-consistent analysis that potentially solves the controversy. We show that all the reported PND experiments in superconducting cuprates are actually compatible with the existence of an IUC magnetism.
Longitudinal Neutron Resonance Spin Echo Spectroscopy under Large Energy Transfers
Authors: Franz C. , Soltwedel O. , Säubert S. , Wendl A. , Gottwald W. , Haslbeck F. , Spitz L. , Pfleiderer C.
Published: December 2019

Longitudinal neutron resonance spin echo (LNRSE) spectroscopy offers very high energy resolution due to the self correction of the resonant spin flippers, and a wide dynamical range nominally exceeding six orders of magnitude in resolution down to sub-ps range. In this paper, the technical realisation how to achieve such low Fourier times at the spectrometer RESEDA at the MLZ Garching is described. The requirements of data collection and data analysis in the limit of very low Fourier times, notably those related to the breakdown of the spin echo approximation, are discussed. A method to infer the scattering function from the experimental data under large energy tansfers beyond the spin echo approximation is presented.
A strategy for handling aberration in Spherical Neutron Polarimetry
Authors: Tosado Jacob , Chen Wangchun , Rodriguez Efrain E.
Published: December 2019

We present a strategy for identifying and correcting for aberration effects in Spherical Neutron Polarimetry. The transformation of the neutron beam polarization vector due to scattering from a material is determined with Spherical Neutron Polarimetry. This neutron scattering technique measures the three cardinal components of the scattered polarization for any chosen cardinal direction of the incident polarization for a given Bragg reflection. As a consequence, the instrumentation required for this technique is desired to be capable of measuring the three-dimensional polarization vector over the sphere. As with all instrumentation, the field of measurement is subject to aberration which must be characterized.
Optimization of a magnetostatic cavity for a 3He spin analyzer on the CANDOR polychromatic reflectometer
Authors: Hassan Md. T. , Chen W.C.
Published: December 2019

A new instrument, the CANDOR (Chromatic Analysis Neutron Diffractometer or Reflectometer) polychromatic beam reflectometer is being built at the National Institute of Standards and Technology Center for Neutron Research. CANDOR will have a capability of polarization analysis for both specular and off-specular scattering, and allow for measuring the magnetic structures of magnetic thin films with a significantly shortened measurement time as compared to a conventional monochromatic beam reflectometer at a continuous neutron source. A critical component of the polarization analysis capability is to develop a 3He neutron spin filter (NSF) for polarization analysis for both specular and off-specular scattering for a continuous wavelength range between 4 Å and 6 Å and a large solid angle coverage for up to 20 energy dispersive detector channels. For ex-situ spin-exchange optical pumping (SEOP) operation, a magnetically shielded solenoid (MSS) will be employed to provide a volume averaged field gradient,

|

▽

→

B
⊥
/
B
|

better than 5×10−4 cm−1 to maintain 3He polarization relaxation times of at least a few hundred hours on the beam line even when there are significant stray fields from a magnet operating at a field up to 3 T at the sample position. We describe a procedure to design, construct, and optimize a MSS with non-identical compensation coil dimensions on the ends to match the scattered neutron beam rays. The volume averaged field gradient is quantified and optimized over a cell for a MSS using the finite-element software package RADIA and compared with that from the experiment.
Stable climate metrics for emissions of short and long-lived species—combining steps and pulses
Authors: Collins William J , Frame David J , Fuglestvedt Jan S , Shine Keith P
Published: December 2019

Multi-gas climate agreements rely on a methodology (widely referred to as ‘metrics’) to place emissions of different gases on a CO2-equivalent scale. There has been an ongoing debate on the extent to which existing metrics serve current climate policy. Endpoint metrics (such as global temperature change potential GTP) are the most closely related to policy goals based on temperature limits (such as Article 2 of the Paris Agreement). However, for short-lived climate forcers (SLCFs), endpoint metrics vary strongly with time horizon making them difficult to apply in practical situations. We show how combining endpoint metrics for a step change in SLCF emissions with a pulse emission of CO2 leads to an endpoint metric that only varies slowly over time horizons of interest. We therefore suggest that these combined step-pulse metrics (denoted combined global warming potential CGWP and combined global temperature change potential CGTP) can be a useful way to include short and long-lived species in the same basket in policy applications—this assumes a single basket approach is preferred by policy makers. The advantage of a combined step-pulse metric for SLCFs is that for species with a lifetime less than 20 years a single time horizon of around 75 years can cover the range of timescales appropriate to the Paris Agreement. These metrics build on recent work using the traditional global warming potential (GWP) metric in a new way, called GWP*. We show how the GWP* relates to CGWP and CGTP and that it systematically underestimates the temperature effects of SLCFs by up to 20%. These step-pulse metrics are all more appropriate than the conventional GWP for comparing the relative contributions of different species to future temperature targets and for SLCFs they are much less dependent on time horizon than GTP.
Combustion characteristics of densified bio-char produced from Gayo Arabica coffee-pulp: Effect of binder
Authors: Setiawan A , Hayat F , Faisal  , Nur T B
Published: December 2019

Increasing number of coffee-by-products highlights its potential as source of renewable energy. The use of coffee pulp as a raw material for bio-briquettes is considered as an effective way to minimize their wastage as landfill. This study aims to examine the combustion characteristics of bio-briquettes produced from Gayo Arabica coffee-pulp which was carbonized through a slow pyrolysis process and densified at a pressure of 150 kg/cm2. Prior to densification process, the raw material was sun-dried, pyrolyzed, ground and sieved to mesh 20. A mixture was then made by adding starch binder at 20, 30 and 40 wt.% followed by molding and drying processes. Characterization of the briquette employs a number of techniques including DSC, bomb calorimeter and proximate analyses as well as combustion test. The results show that the amount of starch-binder significantly affects the rate of combustion and the flame duration. However, no significant change is found in term of calorific value, moisture and ash content.
Mechanical and physical properties of rice straw fiber-reinforced polypropylene composite
Authors: Ismail I , Ismaturrahmi  , Zakaria  , Zulfalina  , Jalil Z , Fadzullah S H
Published: December 2019

In this study, the composite made of rice straw fiber and polypropylene as the adhesive has been produced. The mechanical properties (modulus of rupture, modulus of elasticity, compressive strength) and physical properties (density and thickness swelling) of composite samples have been examined for various compositions of rice straw fibers. The highest modulus of rupture of our composite is found to be 113 kgf/cm2 obtained at the composition of rice straw fiber 40 wt. % and polypropylene 60 wt. %. The highest modulus of elasticity of our composite is 3.5×104 kgf/cm2 obtained at the composition of rice straw fiber 30 wt. % and polypropylene 70 wt. %. The modulus of elasticity tends to decline when the composition of rice straw is increased. The highest compressive strength and density are 8.9 MPa and 0.6 g/cm3, respectively, which are obtained at the formation of rice straw 60 wt. % and polypropylene 40 wt. %. Both compressive strength and density tend to increase when the composition of rice straw fiber is increased. The thickness swelling of the sample was obtained in the range of 0.5 to 1.0 %. Our composites (for all rice straw fiber compositions) have met Indonesian National Standard requirements for particleboard. Based on our results, we recommend producing a composite of rice straw fiber and polypropylene adhesive with an arrangement of 60 wt. % rice straw fiber and 40 wt. % polypropylene.
High photocatalytic activity of TiO2/Fe2O3 nanocomposite prepared by impregnation method for degradation of indigo carmine
Authors: Lubis S , Lelifajri  , Sheilatina  , Ihsan K
Published: December 2019

The photocatalytic degradation of indigo carmine (IC) dye was carried out by using TiO2/Fe2O3 nanocomposite prepared by impregnation method under UV light irradiation. The effect of TiO2 to Fe2O3 mole ratio on the properties and photocatalytic activity of TiO2/Fe2O3 nanocomposite was studied by the prepared three series of TiO2/Fe2O3 nanocomposites with TiO2 to Fe2O3 mole ratio of 1:3, 1:1 and 3:1. The characterization of TiO2/Fe2O3 nanocomposite by XRD showed that the iron (III) oxide extracted from iron ore and calcined at 700°C was in hematite phase (a-Fe2O3). The photocatalytic activity of TiO2/Fe2O3 nanocomposites was determined by using 6 W UV lamps with the wavelength 365 nm and the degradation efficiency of indigo carmine was determined based on UV-Vis spectrophotometer data. The TiO2/Fe2O3 nanocomposite with the the mole ratio of TiO2 to Fe2O3 1:3 showed higher photocatalytic activity than other mole ratio and bare Fe2O3. Degradation efficiency also was highly affected by the initial pH of IC solution, photocatalyst dosage and initial IC concentration. The maximum experimental degradation efficiency of IC was achived at pH value 1 using 0.35 g of photocatalyst and at 20 ppm of initial IC concentration after being irradiated by UV light for 120.
Preparation and characterization of cellulose acetate from cotton
Authors: Huda E , Rahmi  , Khairan
Published: December 2019

The preparation and characterization of cellulose acetate from cotton was conducted in this study. Cotton was hydrolyzed using various concentrations of sulfuric acid (10, 20, 30 and 40%). The bleaching process was performed by using H2O2 solution. The acetylation process was conducted using acetic acid solution. The obtained cellulose acetate was then characterized using Fourier Transform Infrared Spectroscopy (FTIR) in order to observe the functional groups, Scanning Electron Microscopy (SEM) to examine the surface morphology and X-Ray Diffraction (XRD) to observe the crystallinity of cellulose acetate. The results of FTIR analysis confirmed the formation of cellulose acetate. SEM images showed the irregular sizes of cellulose acetate. XRD patterns exhibited that the acetylation process increased the crystallinity of cellulose.
Study on the effect of mesh ratio to the potential distribution of RC cathodic protection using BEM
Authors: Tanjung I , Fonna S , Huzni S
Published: December 2019

Researchers and engineers have used cathodic protection (CP) to prevent corrosion in reinforced concrete (RC). Boundary element method (BEM) is a promising numerical technique to evaluate the effectiveness of CP on RC structures. However, some parameters that might affect the system or the potential distribution, such as mesh ratio, still need to be studied further. This paper aims to study the effect of mesh ratio on the potential distribution of RC installed CP using BEM. Simple 3D beam model of RC was used for the case study. The mesh for the model was triangular element and six variations of the mesh ratio were selected for the study. The mesh ratio obtained from the comparison between the size of the concrete element and the anode or cathode element. Simulation results show that the distribution of potential for all mesh ratios is within the protection criteria (⩽ −850 mV vs Cu/CuSO4). However, the difference between maximum and minimum potential value becomes smaller when the mesh ratio increased. Hence, it shows that the mesh ratio has an effect on the distribution of potential of RC installed CP. However, it is still tolerable since the potential within protection criteria.
Diversity of gastropods epifauna based on substrate in littoral zone in Mesjid Raya, District of Aceh Besar, Indonesia
Authors: Nurhasballah  , Rizki A , Suwarno
Published: December 2019

The gastropod is one class of the Mollusca phylum using the abdomen as the leg. Generally gastropods are crawling on the bottom of the waters and submerged in the mud and are often called epifauna and infauna gastropods. Research on diversity of epifauna gastropods in the littoral zone has been done in Mesjid Raya, Aceh Besar District. This research aims to determine the diversity of gastropod species based on the substrate types (coral reef, muddy and sandy). The exploratory method by using transect line was used in this study. In each substrate, a line transect was drawn for five transects with a length of 50 m. The transects were started from the tidal line. The distance between transects were 50 m. Each transect was made in 10 sampling plots measuring lm × lm, and the distance between plots was 5m. The gastropods were collected directly and without damaging the substrates. The epifauna gastropods obtained was put into a sample bottle and preserved using 70% alcohol. The results showed that 23 families and 54 species of epifauna gastropods were identified. The number of species of gstropods was found in the sandy and muddy substrate more than in the sandy and corral reef substrate, but the highest diversity index was found in the sandy substrate, meanwhile the lowest diversity was found in the coral reef substrate. The highest species density was obtained on Rhinoclavis aspera.
Dead time determination of 2-alkanone homologues series using methanol/water eluent in high performance liquid chromatography system by indirect method
Authors: Idroes R , Muslem  , Saiful  , Mahmudi  , Idroes G M , Suhendra R , Irvanizam  , Zamzami  , Paristiowati M
Published: December 2019

The calculations of the dead time have been done in High Performance Liquid Chromatography System using spreadsheet method. The dead times produced by spreadsheet method were compared to the dead times of iteration method. The dead time were calculated using retention time and carbon number of 2-alkanone that eluted in several eluent composition of methanol/water. The dead time value generated by spreadsheet method shows the dead time value with equally good criteria to iteration method in generating the dead time value as low as possible, where the standard deviation of dead time value against the change of eluent composition is relatively low and the plot linearity of ln(k′) vs nC
is shown to be good.
The determination of depth anomaly in archaeo-magnetic using an Euler deconvolution: Case study in Kuta Lubok fortress
Authors: Zainal M , Yanis M , Darisma D , Marwan  , Ismail N
Published: December 2019

Geophysical surveys have been conducted using magnetic in the archaeological site of Kuta Lubok fortress, Aceh Besar. The fortress was built in 13th century by the Lamuri Sultanate in the northern part Aceh coast. To map an estimated area of archaeological objects, 420 stations have been measured. The data were measured by 21 profiles across of the area with the length of profiles vary from 40 to 60 m. To get a complete resolution, data is taken with a distance of 20 m between lines and a distance of 5 m between stations. From the total magnetic field map that has reduced to the poles, the anomaly is generally able to delineate buried building sites. Then based on Euler deconvolution analysis, the structure of the fortress building can be seen using a 5-meter depth level. But a clearer structure is seen in the use of 10 m in depth. Based on the interpretation of the two tolerance layers it can be concluded that the Kuta Lubok fortress was found stretching parallel to the line along the 400 m to the east of the fort building which is still intact.
One-dimensional magnetotelluric inversion using levenberg-marquardt and particle swarm optimization algorithm
Authors: Darisma D , Marwan
Published: December 2019

Magnetotelluric is a geophysical method which uses natural time variations of the Earth’s magnetic and electric fields. One-dimensional magnetotelluric inversion was carried out to estimate the electrical resistivity distribution of rocks which varied with depth. Non-linear relationships between model parameters and observation data lead to difficulties in the inversion process. This problem can be solved with a non-linear inversion method with a global search technique. One of the global search technique that gaining interest in the inverse problem is Particle Swarm Optimization (PSO). PSO can find acceptable solutions from a very broad set of initial parameters. This study also carried out a non-linear local search technique, namely Levenberg-Marquardt (LM) which has been used globally for the geophysical problem. Then the two inversion algorithm was compared in determining the best model solution. There are two data used in this study which are generated from a three-layer model, namely data without noise and also data that has been added by Gaussian noise with 10% standard deviation. It was found that the results of the two inversions were quite good at determining the actual model. LM algorithm is an algorithm that is truly influenced by the initial value of the damping factor
ε

2 while PSO algorithm depends on several parameters, namely number of particles n, inertia weight w, cognitive parameter c1
and social parameter c2
. Trial experiments suggested that the global best solution could be achieved with controlling parameters w
min = 0.4, w
max = 0.9, c
1 = 1.3 and c
2 = 1.5 without noise data and w
min = 0.7, w
max = 0.9, c
2 = 0.8 and c
2 = 1.4 for data with 10% noise.
Wind disturbance elimination on dual axis solar tracker using fuzzy logic control
Authors: Ikhwan M , Rizal S , Ramli M , Muchlisin Z A , Mardlijah M
Published: December 2019

The use of solar energy using solar panels began to be encouraged. Solar panels utilize solar radiation and convert it into clean and renewable energy. The problems of the accuracy of the panel facing right towards radiation are a challenge in the development of a driving system. Solar panels have limited motion, which is a maximum of phi, so that wind disturbances are very dangerous for motor drives and solar panels. This paper aims to eliminate wind disturbances in solar panel drive systems. The fuzzy logic control is used to determine the amount of power given to the driving motor to direct the panel towards solar radiation. Inputs and outputs of fuzzy controllers are arranged by dividing into each of the five members. Simulation results show that the position error of solar panels without wind disturbances reaches 0.3325° in zonal and 0.5210° in meridional. By using wind disturbances, this system managed to maintain errors smaller than 0.4285° in zonal and 0.6116° in meridional. After modifying the rule base and membership function, systems show decreasing of error half of recent trial.