bluuebunny/crossref_metadata_2025 huggingface dataset:
In situ Metabolite Mass Spectrometry Imaging: New Insights into the
Adrenal Gland
Authors: Li Fengxia , Feuchtinger Annette , Walch Axel , Sun Na
Published: April 2020

The adrenal gland integrates catecholamine-producing neuroendocrine cells and
steroid-producing cells with mesenchymal origin in a structured manner under one
capsule and is a key regulator for vital bioactivity. In addition to
adrenal-specific disease, dysregulation of adrenal hormones is associated with
systemic effects, leading to undesirable metabolic and cardiovascular
consequences. Mass spectrometry imaging (MSI) technique can simultaneously
measure a broad range of biomolecules, including metabolites and hormones, which
has enabled the study of tissue metabolic and hormone alterations in adrenal and
adrenal-related diseases. Furthermore, this technique coupled with labeled
immunohistochemistry staining has enabled the study of the pathophysiological
adaptation of the adrenal gland under normal and abnormal conditions at
different molecular levels. This review discusses the recent applications of in
situ MSI in the adrenal gland. For example, the combination of formalin-fixed
paraffin-embedded tissue microarray and MSI to tissues from patient cohorts has
facilitated the discovery of clinically relevant prognostic biomolecules and
generated promising hypotheses for new sights into physiology and
pathophysiology of adrenal gland. MSI also has enabled the discovery of
clinically significant tissue molecular (i. e., biomarker) and pathway
changes in adrenal disease, particularly in adrenal tumors. In addition, MSI has
advanced the ability to optimally identify and detect adrenal gland specific
molecules. Thus, as a novel analytical methodology, MSI has provided
unprecedented capabilities for in situ tissue study.
HIGH SACRAL HIATUS WITH NON FUSION OF LAMINA OF FIRST SACRAL VERTEBRAE: A CASE REPORT
Authors: Vishal K. , V. Vinay K. , K. Remya , Kumar Arunachalam , K. Shishir
Published: April 2020

Sacrum is a large triangular bone, forming postero-superior wall of the pelvic cavity. During the routine study of bones in the department of Anatomy, an unusual variation in the sacrum was noted. The bone showed high sacral hiatus i.e., at the level of 3rd sacral vertebrae and non-fusion of lamina of 1st sacral vertebrae This type of anomaly is very rare, which prompted us to report the case. The knowledge about this rare variation is important for orthopaedicians and anesthetists since the high sacral hiatus may lead to clinical procedural failures. It is also important for accurate diagnosis of patients with low back pain. Non-fusion of lamina of 1st sacral vertebrae may be associated with spina bifida occulta and may lead to painful condition of back.
EFFECTIVENESS OF AN INFORMATION BOOKLET ON KNOWLEDGE AMONG STAFF NURSES REGARDING PREVENTION AND MANAGEMENT OF PERINEAL TEAR DURING NORMAL DELIVERY
Authors: Fernandes Philomena , Paul Shiney , Savitha B.
Published: April 2020

The study was conducted to evaluate the effectiveness of an information booklet on knowledge among staff nurses regarding the prevention and management of perineal tear during normal delivery. An evaluative approach with one group Pre test Post test design was used for the study. 40 samples were selected using simple random sampling method. The present study was conducted in Justice K. S. Hegde Charitable hospital Mangalore. The collected data were analysed using descriptive and inferential statistics. A significant difference between Pre test and Post test knowledge was found (t = 23.09, p <0.05). The study findings showed that the information booklet was effective in improving knowledge of staff nurses regarding prevention and management of perineal tear during labour. There was no significant association between the level of knowledge and demographic variables.
FOOT DEFORMATIONS IN COCONUT TREE CLIMBERS OF SOUTH INDIA
Authors: George Bincy M. , Kumar Arunachalam , Rao Muddanna S.
Published: April 2020

There are observable foot changes in professional coconut tree climbers of south India, but those are not reported in literature. Objective of the present study was to quantify the foot adaptations in south Indian coconut tree climbers.

Data from a total of 220 male volunteers, between 18-55 years of age, engaged in the profession of coconut tree climbing were collected to find the anatomical changes in foot in them.

The data revealed the coconut tree climbers are having prominent pes cavus, varus foot and abducted great toe. The adaptation pattern of foot varies depending upon the pressure it is subjected to bear.

This study establishes an occupationally induced form of foot deformations or adaptations which are not, reported much in the literature.
Prediction of Postoperative Length of Hospital Stay Based on Differences in Nursing Narratives in Elderly Patients with Epithelial Ovarian Cancer
Authors: Kim Kidong , Han Yoonchang , Jeong Suyeon , Doh Kibbeum , Park Hyeoun-Ae , Lee Kyogu , Cho Moonsuk , Ahn Soyeon
Published: April 2020

Objectives The current study sought to evaluate whether nursing narratives can be used to predict postoperative length of hospital stay (LOS) following curative surgery for ovarian cancer.

Methods A total of 33 patients, aged over 65 years, underwent curative surgery for newly diagnosed ovarian cancer between 2008 and 2012. Based on the median postoperative LOS, patients were divided into two groups: long-stay (>12 days; n = 13) and short-stay (≤12 days; n = 20). Patterns in nursing narratives were examined and compared through a quantitative analysis. Specifically, the total number (TN) of narratives pertaining to care and the standardized number (SN), which was calculated by dividing the TN by the LOS, were compared. Experts evaluated the relevance of the phrases extracted. LOS was then predicted using machine learning techniques.

Results The median postoperative LOS was 18 days (interquartile range [IQR]: 16–24 days) in the long-stay group and 9.5 days (IQR: 8–11.25 days) in the short-stay group. In the long-stay group, surgery duration was longer. Overall, patients in the long-stay group showed a higher volume of nursing narratives compared with patients in the short-stay group (SN: 68 vs. 46, p = 0.021). Thirty-two of the most frequently used nursing narratives were selected from 998 uniquely defined nursing narratives. Multiple t-tests were used to compare the TN and real standardized number (RSN; minimum p < 0.1). Mean and standard deviation of classification results of long-short term memory recurrent neural networks for long and short stays were 0.7774 (0.105), 0.745 (0.098), 0.739 (0.107), and 0.765 (0.115) for F1-measure, precision, recall, and area under the receiver operating characteristic, respectively. Agreement between the differential narratives as assessed by statistical methods and the expert response was low (52.6% agreement; McNemar's test p = 0.012).

Conclusions Statistical tests showed that nursing narratives that utilized the words “urination,” “food supply,” “bowel mobility,” or “pain” were related to hospital stay in elderly females with ovarian cancer. Additionally, machine learning effectively predicted LOS.

Summary The current study sought to determine whether elements of nursing narratives could be used to predict postoperative LOS among elderly ovarian cancer patients. Results indicated that nursing narratives that used the words “urination,” “food supply,” “bowel mobility,” and “pain” significantly predicted postoperative LOS in the study population. Additionally, it was found that machine learning could effectively predict LOS based on quantitative characteristics of nursing narratives.
Locking Plate Fixation for Canine Acetabular Fractures
Authors: Piana Francesco , Solano Miguel , Kalff Stephen , Yeadon Russell
Published: April 2020

Objective The aim of this study was to document application of locking plates for stabilization of acetabular fractures along with complications and clinical outcomes. We hypothesized that complications and clinical outcomes would be comparable to historical reports using non-locking plate and screw constructs.

Study Design Medical records of dogs presented with acetabular fractures at a single referral centre between 2010 and 2018 were reviewed. Cases surgically managed by open reduction and internal fixation, involving placement of at least one locking plate and screws, were included. Signalment, fracture classification, type of implant used, additional methods of stabilization, along with complications and neurological deficits, were collected. Long-term follow-up was based on Liverpool Osteoarthritis in Dogs questionnaire.

Results Eighteen acetabula were repaired in 17 dogs. Locking implants were VetLOX (4/18), string-of-pearls (7/18) and locking compression plates (7/18). Locking plates and screws were used as the sole method of fixation in 10/18 acetabula, and as adjunctive fixation with other implants in 8/18 acetabula. Two minor complications and one catastrophic complication were reported. Sixteen of seventeen dogs returned to function with radiographic documentation of fracture healing. Complication rate was comparable to historic reports using non-locking implants. Long-term outcomes assessed by Liverpool Osteoarthritis in Dogs questionnaire were positive in most cases.

Conclusion Locking plates are a viable means of stabilizing acetabular fractures in dogs and can provide positive clinical outcomes. Surprisingly, problems including inaccurate fracture reduction and implant loosening were not fully avoided by use of locking implants but incidence was low.
Laser control of molecular rotation: Expanding the utility of an optical centrifuge
Authors: MacPhail-Bartley Ian , Wasserman Walter W. , Milner Alexander A. , Milner Valery
Published: April 2020

Since its invention in 1999, the optical centrifuge has become a powerful tool for controlling molecular rotation and studying molecular dynamics and molecular properties at extreme levels of rotational excitation. This technique has been applied to a variety of molecular species, from simple linear molecules to symmetric and asymmetric tops, to molecular ions and chiral enantiomers. Properties of isolated ultrafast rotating molecules, the so-called molecular superrotors, have been investigated, as well as their collisions with one another and the interaction with external fields. The ability of an optical centrifuge to spin a particular molecule of interest depends on both the molecular structure and the parameters of the centrifuge laser pulse. An interplay between these two factors dictates the utility of an optical centrifuge in any specific application. Here, we discuss the strategy of assessing and adjusting the properties of the centrifuge to those of the molecular rotors and describe two practical examples of optical centrifuges with very different characteristics, implemented experimentally in our laboratory.
Boron influence on bandgap and photoluminescence in BGaN grown on AlN
Authors: Zdanowicz E. , Iida D. , Pawlaczyk L. , Serafinczuk J. , Szukiewicz R. , Kudrawiec R. , Hommel D. , Ohkawa K.
Published: April 2020

Since the BGaN alloy is considered a promising material in the wide range of optoelectronic applications, a detailed study of its band structure and optical properties is highly demanded. Here, BxGa1−xN layers with 0.5%, 1.1%, and 1.2% B were grown by metalorganic vapor-phase epitaxy on AlN/sapphire templates and investigated by structural and optical methods. The bandgaps of the investigated alloys were examined by contactless electroreflectance (CER) spectroscopy. Because no GaN layer is present in the investigated samples, the detected CER resonances do not overlap with the GaN-related signal, which is typical for BGaN layers grown on GaN templates. Thus, the energy of the bandgap-related transition in BGaN samples can be unambiguously determined from the resonances observed in the CER spectra. The boron-induced redshift of the bandgap was determined to be about 60 meV/% B for the studied samples. By means of photoluminescence measurements, the deteriorating optical quality of samples with increasing boron content is shown as the decreasing bandgap- to defect-related emission intensity ratio. What is more, the defect-related emission is shifted from typical for GaN yellow range to the red and is located at 1.9 eV for all BGaN samples.
Simplified equivalent circuit approach for designing time-domain responses of waveform-selective metasurfaces
Authors: Asano Kosei , Nakasha Tomoyuki , Wakatsuchi Hiroki
Published: April 2020

In this study, we demonstrate simplified equivalent circuit models to effectively approximate responses of recently reported waveform-selective metasurfaces that distinguish different electromagnetic waves even at the same frequency depending on their waveforms or pulse widths. Compared to conventional equivalent circuit models that represent behaviors of ordinary metasurfaces in the “frequency” domain, the proposed models enable us to explain how waveform-selective metasurfaces respond in the “time” domain. Our approach well estimates not only time constants of waveform-selective metasurfaces but also their entire time-domain responses. Particularly, this study reports the importance of resistive components of diodes as well as the limitation of our models with respect to the power dependence although still the models effectively work when waveform-selective mechanisms are clearly exhibited with a sufficiently large input power. Thus, the idea of the proposed equivalent circuit models contributes not only to a greater understanding of waveform-selective mechanisms but also to facilitating the design process of such unique structures.
Short-pulse KrF amplifier using spatially tunable x-ray preionization
Authors: Szatmári S.
Published: April 2020

The small saturation energy density of excimers requires amplifiers of large cross sections for amplification of short pulses of already medium power. Homogeneous excitation of large volumes of fluorine-based gas mixtures by discharge pumping is a critical interplay of the properties of both pumping and preionization, generally necessitating an intense spatially and temporally controlled x-ray preionization. In the present realization, the stringent intensity requirements of preionization are fulfilled by reducing the pulse duration of the x-ray flash to ∼16 ns and by positioning the x-ray source in the near vicinity of the active volume. It is proven both theoretically and experimentally that by proper choice of the positions of two cylindrical x-ray guns, the spatial distribution of preionization can be tuned to (and around) the optimum distribution. In this way, the spatial distribution of the discharge can also be controlled, giving a practical method to compensate for eventual inhomogenities of the E-field of excitation and to tune the discharge to the desired geometry. In this paper, design considerations and experimental realization of a KrF excimer amplifier of ∼5 × 4 cm2 cross section and a spatially tunable x-ray preionization are presented.
Numerical analysis of the optical pumping process coupled with 23Na D2 manifold modeled as a partially resolved hyperfine structure
Authors: Zhang Xiaoxu , Ma Xingqiao , Chen Yiping , Ren Qiongying , Zhao Hua
Published: April 2020

All magnetometers using alkali atoms rely on the monochromatic light driving the optical pumping process in the D1 or D2 line to create spin-polarized atoms. In the study of a sodium (Na) magnetometer, we find that 23Na exhibits the same hyperfine structure as exhibited by the 87Rb atom but differs from Rb in terms of level splitting. The narrowly split hyperfine levels of the 23Na 3P3/2 excited state are comparable to its natural broadening (9.8 MHz). We have modeled the nearly unresolved hyperfine structure as a partially resolved multilevel system in which the absorption at each photon detuning will induce adjacent allowed transition pathways simultaneously. Thus, the corresponding optical pumping processes of 23Na and 87Rb are governed by similar rate equations but result in different redistributed populations. By numerically solving the rate equations, we demonstrate that optically pumped 23Na has a much smaller spin polarization than that of 87Rb because the population imbalances between the ground state Zeeman levels of 23Na are very small. The inefficient optical pumping can explain why Na magnetometers are not studied extensively. The investigation into the optical pumping process of 23Na is helpful in preparing a highly spin-polarized atomic medium and optimizing the sensitivity of Na magnetometers.
Density-inversion method for the Kohn–Sham potential: Role of the screening density
Authors: Callow Timothy J. , Lathiotakis Nektarios N. , Gidopoulos Nikitas I.
Published: April 2020

We present a method to invert a given density and find the Kohn–Sham (KS) potential in Density Functional Theory (DFT) that shares the density. Our method employs the concept of screening density, which is naturally constrained by the inversion procedure and thus ensures that the density being inverted leads to a smooth KS potential with correct asymptotic behavior. We demonstrate the applicability of our method by inverting both local and non-local (Hartree–Fock and coupled cluster) densities; we also show how the method can be used to mitigate the effects of self-interactions in common DFT potentials with appropriate constraints on the screening density.
Raman scattering microscopy imaging of basal plane stacking faults and associated partial dislocations in 4H-SiC crystals
Authors: Shimada Kana , Asada Kanta , Yodo Mikako , Ohtani Noboru
Published: April 2020

A novel characterization method using Raman scattering microscopy for basal plane stacking faults (SFs) and associated partial dislocations (PDs) in 4H-SiC crystals is proposed. Atomically thin SFs were successfully detected through the peak shift of the A1t transverse optical phonon mode in 4H-SiC, which could induce an electrical dipole moment within the SFs. The A1t mode was also sensitive to the strain field around the PDs encompassing SFs. Raman scattering microscopy imaging was able to determine the core type of PDs and their line direction within the crystals. Numerical simulation of Raman scattering microscopy images of PDs was also conducted and showed a quantitative agreement with the experimentally obtained images. Finally, the method was applied to the investigation of expansion behaviors of double Shockley SFs (DSSFs) in heavily nitrogen-doped 4H-SiC crystals during high temperature annealing and revealed several important aspects of DSSF expansion.
Geometric charges and nonlinear elasticity of two-dimensional elastic metamaterials
Authors: Bar-Sinai Yohai , Librandi Gabriele , Bertoldi Katia , Moshe Michael
Published: April 2020

Problems of flexible mechanical metamaterials, and highly deformable porous solids in general, are rich and complex due to their nonlinear mechanics and the presence of nontrivial geometrical effects. While numeric approaches are successful, analytic tools and conceptual frameworks are largely lacking. Using an analogy with electrostatics, and building on recent developments in a nonlinear geometric formulation of elasticity, we develop a formalism that maps the two-dimensional (2D) elastic problem into that of nonlinear interaction of elastic charges. This approach offers an intuitive conceptual framework, qualitatively explaining the linear response, the onset of mechanical instability, and aspects of the postinstability state. Apart from intuition, the formalism also quantitatively reproduces full numeric simulations of several prototypical 2D structures. Possible applications of the tools developed in this work for the study of ordered and disordered 2D porous elastic metamaterials are discussed.
Characterization of the coformycin biosynthetic gene cluster in
Streptomyces kaniharaensis
Authors: Ren Daan , Ruszczycky Mark W. , Ko Yeonjin , Wang Shao-An , Ogasawara Yasushi , Kim Minje , Liu Hung-wen
Published: April 2020

Significance

Coformycin and pentostatin are potent nucleoside inhibitors of adenosine deaminase with anticancer activity due to their structurally unique 1, 3-diazepine nucleobases. Herein, the biosynthetic pathway of coformycin is reconstituted in vitro, demonstrating that it directly overlaps with the early stages of
l
-histidine biosynthesis. The key branch point between the coformycin and
l
-histidine pathways involves a seven-membered ring cyclization reaction that likely proceeds via Dieckmann cyclization and retro-aldol elimination. This reaction is catalyzed in an ATP-dependent manner, although phosphorylation of the substrate does not appear to be a part of the catalytic cycle. This suggests a regulatory role for ATP that may be important for modulating competition for shared resources between the metabolic processes of L-histidine and coformycin biosynthesis.
Resistance training attenuates circulating FGF‐21 and myostatin and improves insulin resistance in elderly men with and without type 2 diabetes mellitus: A randomised controlled clinical trial
Authors: Shabkhiz Fatemeh , Khalafi Mousa , Rosenkranz Sara , Karimi Pouran , Moghadami Kamilia
Published: April 2020

Fibroblast growth factor 21 (FGF‐21) and myostatin have been proposed to be potential therapeutic target for insulin resistance in age‐related metabolic disorders including type 2 diabetes (T2D). Moreover, despite the potential metabolic effect of resistance training on insulin resistance, aging, and T2D; the effect of this type of exercise training on FGF‐21 and myostatin in elderly men with and without T2D are unknown. Forty‐four elderly men were assigned to either the RT training (RT; without T2D: 12, with TD2 = 10) or the control group (C; without T2D: 12, with TD2 = 10). The RT group performed 12‐wk resistance training intervention, 3 days/wk, 10 repetitions with 70% 1RM. At the baseline, the elderly men with T2D had a higher FGF‐21 (p = 0.002) and myostatin (p = 0.02) concentrations and lower muscle strength (p = 0.01) than the elderly men without T2D. RT resulted in significant decrease in FGF‐21 and myostatin concentration and increase in muscle strength in both elderly men with and without T2D (P = 0.001, for all) as well as decrease in HOMA‐IR in only elderly men without T2D (P = 0.001). There was no significant difference in the RT‐induced FGF‐21 reduction between elderly men with and without T2D (p = 0.77, p = 0.28, respectively), but, RT caused a larger reduction in circulating myostatin in elderly men without T2D than with T2D (P = 0.007). Taken together, our results demonstrated that 12 weeks of RT induced an overall significant reduction of FGF‐21 and myostatin in elderly men with and without T2D; with higher reduction of myostatin in elderly men without T2D.
Gmunu: toward multigrid based Einstein field equations solver for general-relativistic hydrodynamics simulations
Authors: Cheong Patrick Chi-Kit , Lin Lap-Ming , Li Tjonnie Guang Feng
Published: April 2020

We present a new open-source axisymmetric general relativistic hydrodynamics code Gmunu (general-relativistic multigrid numerical solver) which uses a multigrid method to solve the elliptic metric equations in the conformally flat condition (CFC) approximation on a spherical grid. Most of the existing relativistic hydrodynamics codes are based on formulations which rely on a free-evolution approach of numerical relativity, where the metric variables are determined by hyperbolic equations without enforcing the constraint equations in the evolution. On the other hand, although a fully constrained-evolution formulation is theoretical more appealing and should lead to more stable and accurate simulations, such an approach is not widely used because solving the elliptic-type constraint equations during the evolution is in general more computationally expensive than hyperbolic free-evolution schemes. Multigrid methods solve differential equations with a hierarchy of discretizations and its computational cost is generally lower than other methods such as direct methods, relaxation methods, successive over-relaxation. With multigrid acceleration, one can solve the metric equations on a comparable time scale as solving the hydrodynamics equations. This would potentially make a fully constrained-evolution formulation more affordable in numerical relativity simulations. As a first step to assess the performance and robustness of multigrid methods in relativistic simulations, we develop a hydrodynamics code that makes use of standard finite-volume methods coupled with a multigrid metric solver to solve the Einstein equations in the CFC approximation. In this paper, we present the methodology and implementation of our code Gmunu and its properties and performance in some benchmarking relativistic hydrodynamics problems.
Convolutional neural networks for direct detection of dark matter
Authors: Khosa Charanjit K , Mars Lucy , Richards Joel , Sanz Veronica
Published: April 2020

The XENON1T experiment uses a time projection chamber (TPC) with liquid xenon to search for weakly interacting massive particles (WIMPs), a proposed dark matter particle, via direct detection. As this experiment relies on capturing rare events, the focus is on achieving a high recall of WIMP events. Hence the ability to distinguish between WIMP and the background is extremely important. To accomplish this, we suggest using convolutional neural networks (CNNs); a machine learning procedure mainly used in image recognition tasks. To explore this technique we use XENON collaboration open-source software to simulate the TPC graphical output of dark matter signals and main backgrounds. A CNN turns out to be a suitable tool for this purpose, as it can identify features in the images that differentiate the two types of events without the need to manipulate or remove data in order to focus on a particular region of the detector. We find that the CNN can distinguish between the dominant background events (ER) and 500 GeV WIMP events with a recall of 93.4%, precision of 81.2% and an accuracy of 87.2%.
Dynamic trapping and releasing photonics beyond delay-bandwidth limit in cascaded photonic crystal nanocavities
Authors: Xu Zhe-Ming , Li Chao , Wu Jun-Fang
Published: April 2020

Controlling the flow of light on-chip is of great importance for quantum computing and optical signal processing. In this paper, we present a theoretical study to reveal the underlying physics of how to effectively trap, store and release a signal pulse, and eventually break the delay-bandwidth limit, based on controllable EIT-like effect in dynamically tuned standing-wave cascaded nanocavities. Using this mechanism, we design a compact silicon photonic crystal system with long storing time and a delay-bandwidth product over 460, which is about two orders of magnitude greater than the reported results obtained by other methods based on static resonator system, and the trapped signal pulse can be released on demand.
The empirical study on energy embodied in goods of Sino-US trade
Authors: Liu Xiaolei , Chu Chunchao
Published: April 2020

The huge trade surplus of Sino-US trade is founded on large net exports of embodied energy because of the energy’s dual nature which is not only commodity and also factor input. In this paper, energy embodied in goods of Sino-US trade of 2015 is calculated quantitatively based on Input-Output analysis approach. The results show that the net export of embodied energy was 341.75 million tce (tons of coal equivalent). Due to the scarcity of energy endowments in China, over net export of embodied energy for trading interest is against sustainable development which is one of basic state policies .The author gives some advices based on empirical analysis.
Modified flower-like nickel oxide on carbon paste electrode (CPE) for analysis cholesterol based on non-enzymatic sensor
Authors: Suropati R T L , Wibowo R , Nurani D A , Krisnandi Y K
Published: April 2020

The increasing circulation of unhealthy foods in various places threatens the community of malnutrition. One of which is the intake of cholesterol nutrition. When the normal limit is exceeded, it can trigger the spread of various diseases such as coronary heart disease. To anticipate the outbreak of the disease, a practical, stable, simple, and relatively inexpensive, non-enzymatic sensor device for monitoring blood cholesterol levels in some food samples such as milk and meat was developed. In this research, nickel modified catalyst on carbon paste electrodes, NiO/CPE by hydrothermal method and Ni/CPE by electrochemical method were developed. A flower-like morphology for NiO was obtained from hydrothermal method and rock-like morphology was obtained from nickel deposit. Results showed that Ni/CPE worked optimally at pH 14 with sensitivity of 0.8148 μA μM−1 cm−2 and limit of detection (LoD) of 0.1645 μM, while NiO/CPE worked optimally at pH 12 with a sensitivity of 0.1238 μA μM−1 cm−2 and LoD of 0.7804 μM. Cholesterol level measurement from the packaged milk sample showed differences of 20.42 % and 47.18 % from the nutrition table information for Ni/CPE and NiO/CPE, respectively.
Arsenic and arsenate detection with anodic stripping voltammetry technique using boron-doped diamond modified by platinum
Authors: Sitorus R , Saefumillah A , Ivandini T A
Published: April 2020

High homogeneity and stability of platinum particles modified at boron-doped diamond (BDD) electrode was successfully performed using chemical seeding, followed by electrodeposition technique. The platinum particles on the surface of BDD characterized using Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy (SEM-EDS) showed that the coverage of Pt particles was 1.54 % on the BDD surface. These modified electrodes were used for As3+ and As5+ sensors using the anodic stripping voltammetry technique in 0.1 M phosphate buffer solution pH 6. Prior to the detection, pretreatment was required by the addition of 0.1 M NaBH4 to change As5+ to As3+. The optimum parameters were at a deposition potential of -500 mV, a deposition time of 150 s, and a scan rate of 200 mV/s. The voltammograms were linear for As3+ and As5+ (R2 = 0.9797 and 0.9903, respectively) in the concentration range of 0 to 100 ppb. Estimated detection limits of 16.50 and 8.19 ppb for AS3+ and As5+ were achieved, respectively, suggesting that the method is promising for the specification detection of As3+ and As5+.
Synthesis of impregnated Ni(0) zeolite ZSM-5 as catalyst for carboxylation reaction of acetylene with CO2
Authors: Mujiantono F , Abdullah I , Krisnandi Y K
Published: April 2020

Conversion of carbon dioxide (CO2) into other compounds has become very advantageous because of the abundance in the atmosphere. However, carbon dioxide (CO2) is thermodynamically and kinetically stable so it needs low valence metal such as Ni(0) to be activated and react with other compounds. In this study, nickel metal-impregnated ZSM-5 was prepared as heterogeneous catalyst for carboxylation reaction of acetylene with carbon dioxide. Microporous and hierarchical ZSM-5 were synthesized using single template and double template, respectively. X-Ray Diffraction (XRD) characterization results show that ZSM-5 material with high crytallinity was successfully synthesized. Scanning Electron Microscopy (SEM) images show ZSM-5 has hexagonal coffin-like morphology. Brunauer-Emmett-Teller (BET) surface area analysis proves that the ZSM-5 has combination of micro and meso-sized pores (hierarchical pores). The elemental analysis using Atomic Absorption Spectroscopy (AAS) gives nickel content of 1.9 % in microporous ZSM-5 and 2.1 % in hierarchical ZSM-5. HPLC analysis show new peak is observed at retention time of 3.6 minutes for carboxylation reaction of acetylene (CO2: acetylene of 0.2:0.8) with optimum condition at 12 h and 80 °C when using microporous Ni/ZSM-5 or hierarchical counterpart as catalyst.
Crude glycerol from waste cooking oil treatment as an alternative solvent in synthesis of diethyl-2,6-dimethyl-4-phenyl-1,4-dihydropyridine-3,5-dicarboxylate
Authors: Cahyana A H , Ardiansah B , Hanifah H
Published: April 2020

Diethyl-2,6-dimethyl-4-phenyl-1,4-dihydropyridine-3,5-dicarboxylate, a 1,4-DHP derivative, has been synthesized from benzaldehyde, ethyl acetoacetate and ammonium acetate via a one-pot three component reaction in crude glycerol as solvent. Crude glycerol was obtained from the treatment of waste cooking oil. The product was obtained in 69 % yield when the reaction was conducted at 90 °C for 1 h under reflux in 10 mL glycerol.
Modification of boron-doped diamond with gold through wet-chemical seeding and electrodeposition techniques for the application of acrylamide biosensor
Authors: Anggraini L E , Saepudin E , Ivandini T A
Published: April 2020

Acrylamide is known as carcinogenic and neurotoxin substrates. An alternative method for acrylamide detection is by using hemoglobin-based biosensors as it can provide a simple, rapid, and sensitive method. In this research, the electrodes for biosensor of acrylamide were prepared by modifying boron-doped diamond (BDD) with gold and hemoglobin (Hb). Wet-chemical seeding followed by electrochemical overgrowth of seeds technique was performed to modify the BDD electrodes with gold. The characterization with Scanning Electron Microscopy-Energy Dispersive Spectroscopy X-Ray (SEM-EDS) showed the gold coverage of 12.74 % on the BDD surface. The gold-modified BDD was then modified with 0.25 mM Hb. The prepared sensor can be successfully applied in the concentration range of acrylamide from 0.6 to 6 μM with high linearity (R2 = 0.9901) and an estimated limit of detection of 0.845 μM.
Synthesis of impregnated nickel-mesoporous carbon and its application for reaction of acetylene with carbon dioxide
Authors: Kawigraha A D H , Krisnandi Y K , Abdullah I
Published: April 2020

Mesoporous carbon has been synthesized using soft-template method with phloroglucinol as carbon precursor and pluronic F127 as a template to form mesosize pores in carbon structure. The Brunauer-Emmett-Teller (BET) results prove the existence of hysteresis loop and adsorption isotherm type IV with total surface area of 432.498 m2/g and pore diameter of 7.46 nm. The mesoporous carbon was then impregnated with various amount of nickel metal using Ni(NO3)2 as precursor, followed by four ways of reduction: (1) with ethylene glycol in aqueous solution; (2) with ethylene glycol in 98 % ethanol in water; (3) with NaBH4; and (4) with H2 gas. Energy Dispersive X-Ray (EDX) analysis shows that nickel content in materials after reduction were (1) 34.48 %, (2) 0.02 %, (3) 0.9 % and (4) 1.73 %, in respective to the reduction methods. X-Ray Diffraction (XRD) patterns of mesoporous carbon reduced with NaBH4 and H2 show no change in mesoporous carbon structure, especially for peak at 2θ of 24.44° and 43.18°. After impregnation, the materials were further tested for their catalytic activity for acetylene reactions with CO2. The reactions were conducted in a 100 mL batch reactor with a pressure ratio of acetylene to CO2 of 0.2:0.8. Some reaction conditions were examined to determine the effect on the reaction: reaction time (3, 6, 12) h and reaction temperature (25, 40 and 80) °C. Product analysis using High Performance Liquid Chromatography (HPLC) shows that new peak appears at retention time of 3.625 minutes. The optimum condition was obtained at 25 °C and 3 hours.
Facile synthesis and growth mechanism of mesoporous anatase titanium dioxide nanoparticles via sol-gel method
Authors: Rahmaningsih G , Gunlazuardi J , Khalil M
Published: April 2020

An investigation on the synthesis of highly monodispersed mesoporous anatase titanium dioxide (TiO2) nanoparticles has been reported in this work. The mesoporous nanoparticles were obtained by a facile sol-gel method where titanium isopropoxide (TTIP) was used as the titanium precursor in basic solution. Here, the effect of reaction time was studied to study the growing mechanism of TiO2 nanocrystal. The as-synthesized nanoparticles were characterized with X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR), Brunauer-Emmett-Teller (BET) Surface Area Analyzer, and High Resolution Tunneling Electron Microscopy (HR-TEM). Based on the result, it is found that a highly monodispersed mesoporous anatase TiO2 nanoparticles with large surface area could successfully be synthesized. It is also believed that the morphology of as-synthesized particles could easily be controlled by the reaction time. Results show that uniform mesoporous TiO2 nanoparticles with perfect spherical morphology could be obtained when the reaction was performed in 3 hours of reaction time.
Superabsorbent nanocomposite as micronutrient slow-release fertilizer
Authors: Helmiyati H , Nugraha D
Published: April 2020

In this research, sodium alginate grafted by poly(acrylate-co-acrylamide) loaded montmorillonite (MMT) and the addition of boric acid as micronutrients into the superabsorbent nanocomposite through in-situ method have been successfully synthesized. We developed superabsorbent nanocomposite with montmorillonite obtained by increasing the amount of montmorolite, which would increase the swelling capacity and by adding boric acid micronutrients will also increase water swelling capacity. The best swelling capacity to water of superabsorbent nanocomposite obtained 426.337 g/g that formulated with MMT contents approximately 20.0 % wt and 0.1 g boric acid. The optimal release capacity of boric acid is 25.561 % for 8000 min or about 6 days. This is supported by the study of kinetics for the water swelling in pseudo second-order while the boric acid release is pseudo first-order obtained. The nanocomposite superabsorbents that are successfully synthesized show that the release of boric acid micronutrients as slow release can be controlled and denoted interesting materials to be applied in agriculture.
Synergistic effect of magnetite and carbonous materials incorporated with iron (III)-doped ZnO on the photodegradation of organic dyes
Authors: Pratiwi M I , Saleh R
Published: April 2020

Fe-doped ZnO (Fe:ZnO) was combined with both magnetite (Fe3O4) and carbonous materials (graphene) using a co-precipitation method to form Fe:ZnO/G/Fe3O4 nanocomposites with various weight ratios (1:0, 1:0.05, 1:0.1, 1:0.3, 1:0.5, and 1:1). These nanocomposites were characterized using different methods of measurements; such as Fourier transform infrared spectroscopy to record the absorption spectra of certain functional groups, X-ray diffraction spectroscopy to identify the structure of the samples, and thermogravimetric analysis to study the loss in samples’ weight under increasing temperature. The magnetite and carbonous materials were used to support Fe:ZnO in the photodegradation of methylene blue dye, as a representation of organic dyes. The photocatalytic activity was examined under ultra violet (UV) light irradiation. The effects of Fe:ZnO/G:Fe3O4 ratio, scavenger addition, and catalyst dosage on the photocatalytic activity were also studied. Finally, the reusability of the catalyst was examined and proved.
Efficient photo-, sono-, and sonophoto-fenton-like degradation of the organic pollutant methylene blue using a BiFeO3/graphene composite
Authors: Susanti Y D , Saleh R
Published: April 2020

In this study, we investigated the degradation of the organic pollutant methylene blue (MB) using photo-, sono-, and sonophoto-fenton processes under visible light, ultrasonic irradiation, and a combination of the two, respectively, in the presence of an iron-containing perovskite catalyst BiFeO3/graphene composite. The sample structure was characterized using X-ray diffraction; thermal analyses were performed using thermogravimetric analysis and differential thermal analysis; and the BiFeO3/graphene composite was prepared using a hydrothermal method. We observed better MB degradation via the BiFeO3/graphene composite using the sonophoto-fenton method relative to either the photo- or sono-fenton methods, with increased MB degradation occurring through the synergistic effects of both the photo- and sono-fenton techniques. Furthermore, addition of a chelating agent, such as ascorbic acid, to the photo- and sono-fenton reactions enhanced MB degradation.
Observation of the domain wall propagation in CoFe and CoFeB nanowires driven by sub-nanosecond magnetic pulse using micromagnetic simulation
Authors: Hawibowo S , Kurniawan C , Djuhana D
Published: April 2020

In this study, we have observed the domain wall (DW) propagation in CoFe and CoFeB nanowires driven by sub-nanosecond magnetic pulse using micromagnetic simulation approach. The length of the nanowire is 2000 nm, the widths are varied of 50, 100, and 150 nm, and the thicknesses are 2.5 and 5.0 nm. The simulation was performed using a rectangular cell size of 5×5×t nm3 with t is the thickness of the nanowire and the damping factor is 0.05. The sub-nanosecond magnetic pulse length of 0.5 ns was used to move DW through the nanowire. We found that the DW velocity increased as the magnitude of magnetic pulse increased then abruptly decreased which known as the Walker Breakdown (H
WB). The transverse type DW structure is observed below the H
WB field while vortex/anti-vortex wall structure was formed above H
WB. We found that the H
WB value of CoFe and CoFeB decreased as the width and thickness of the nanowire increased. The increasing of nanowire thickness also caused the velocity reduction of DW. The energy competition between exchange and demagnetization energy contributed to the DW structure during propagation. The exchange energy is higher than the demagnetization energy as the formation of vortex/anti-vortex wall.
The photo-, sono-, and sonophoto-catalytic activity of an LaMnO3/TiO2/graphene composite for degrading methylene blue in wastewater
Authors: Susanti Y D , Triyono D , Saleh R
Published: April 2020

Here we describe the successful synthesis of an LaMnO3/TiO2/graphene composite using a co-precipitation method and three different weight percentages (wt%) of graphene. The structure of the sample was characterized using X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) spectroscopy, and the thermal stability of the sample was characterized using thermogravimetric analysis (TGA) and differential thermal analysis. The XRD pattern of the sample confirmed the orthorhombic phase of the LaMnO3 nanoparticle and anatase phase of the TiO2 nanoparticle; however, the graphene peak unidentifiable by XRD was confirmed using TGA and FTIR spectroscopy. Moreover, we found that the photo-, sono-, and photosono-catalytic activities of LaMnO3/TiO2 were elevated by the presence of graphene material as an electron trapper, resulting in optimal rates of methylene blue degradation in the presence of 5 wt.% graphene.
Hysteresis observation of CoFe and CoFeB model disk using micromagnetic simulation
Authors: Mustaghfiroh Q , Djuhana D , Kurniawan C
Published: April 2020

In this work, hysteresis loop of CoFe and CoFeB disk ferromagnets are observed by using micromagnetic simulation OOMMF based on LLG equation. The diameter varied from 50–500 nm with the thickness 5 nm and 10 nm. For simulation process, the damping factor of 0.05 and the cell size 2.5 × 2.5 × 2.5 nm3 were fixed. We applied parallel and perpendicular external field to generate hysteresis loop of CoFe and CoFeB disk ferromagnets. Interestingly, we found two behaviours of coercivity, first less than diameter 100 nm and second, greater than 100 nm. For parallel-applied field of CoFe and CoFeB, the coercivity showed fluctuation around 20–160 mT. Greater than diameter 100 nm, the coercivity in a constant value around 40 mT for CoFe and around 20 mT for CoFeB. For perpendicular applied field of CoFe, we still observed the coercivity around 40 mT but greater than 100 nm, the coercivity dropped to zero. For CoFeB with perpendicular applied field, the coercivity decrease as the diameter increase until reach diameter 100 nm. Greater than the diameter 100 nm, the coercivity is constant at 20 mT. According to the results, we had observed the Perpendicular Magnetic Anisotropy (PMA) behaviour in both CoFe and CoFeB disk ferromagnets with certain value of the coercivity when the field applied in perpendicular direction.
Symmetries of shamrocks IV: The self-complementary case
Authors: Ciucu Mihai
Published: April 2020

In this paper we enumerate the centrally symmetric lozenge tilings of a hexagon with a shamrock removed from its center. Our proof is based on a variant of Kuo’s graphical condensation method in which only three of the four involved vertices are on the same face. As a special case, we obtain a new proof of the enumeration of the self-complementary plane partitions.
Various Types of Perceived Job Discrimination and Sleep Health Among Working Women: Findings From the Sister Study
Authors: Lee Soomi , Chang Anne-Marie , Buxton Orfeu M , Jackson Chandra L
Published: April 2020

Job discrimination, a social stressor, may lead to sleep health disparities among workers; yet, limited research has examined this relationship and specific sources of job discrimination. We used a US sample of working women (n = 26,085), participants in the Sister Study (2008–2016), to examine the associations of perceived job discrimination due to sex, race, age, health conditions, and/or sexual orientation with sleep health. Cross-sectionally, linear or logistic regression models revealed that each source of job discrimination was independently associated with different sleep problems after controlling for other sources of job discrimination. Longitudinally, among participants without short sleep (<7 hours/night) at time 1 (2012–2014), age-specific job discrimination was associated with 21% increased odds of new-onset short sleep (odds ratio = 1.21, 95% confidence interval: 1.03, 1.43) at time 2 (2014–2016). Among those without insomnia symptoms at time 1, race-specific job discrimination was associated with 37% increased odds of new-onset insomnia symptoms (odds ratio = 1.37, 95% confidence interval: 1.07, 1.75) at time 2. Sex- and health-specific job discrimination also predicted new-onset sleepiness. There were dose-response relationships such that a greater number of sources of job discrimination (≥3) was associated with greater odds of prevalent and incident sleep problems. Perceived job discrimination may contribute to working women’s poor sleep health over time, raising concerns about sleep health disparities emanating from the workplace.
The impact of compound library size on the performance of scoring functions for structure-based virtual screening
Authors: Fresnais Louison , Ballester Pedro J
Published: April 2020

Larger training datasets have been shown to improve the accuracy of machine learning (ML)-based scoring functions (SFs) for structure-based virtual screening (SBVS). In addition, massive test sets for SBVS, known as ultra-large compound libraries, have been demonstrated to enable the fast discovery of selective drug leads with low-nanomolar potency. This proof-of-concept was carried out on two targets using a single docking tool along with its SF. It is thus unclear whether this high level of performance would generalise to other targets, docking tools and SFs. We found that screening a larger compound library results in more potent actives being identified in all six additional targets using a different docking tool along with its classical SF. Furthermore, we established that a way to improve the potency of the retrieved molecules further is to rank them with more accurate ML-based SFs (we found this to be true in four of the six targets; the difference was not significant in the remaining two targets). A 3-fold increase in average hit rate across targets was also achieved by the ML-based SFs. Lastly, we observed that classical and ML-based SFs often find different actives, which supports using both types of SFs on those targets.