bluuebunny/crossref_metadata_2025 huggingface dataset:
Observation of flat band, RKKY plateau, and magnetization jump in quasi-one-dimensional triangular kagome lattice model
Authors: Zare Moslem
Published: October 2020

Inspired by the research interest on the realization of flatbands and magnetization plateaus in kagome lattices, herein we study the electronic properties and exchange magnetic interactions in quasi-one-dimensional boron triangular kagome lattice (1D-BTKL) models by using the real-space Green’s function approach in a tight-binding model. First, we study the electronic properties of 1D-BTKLs in the presence of staggered sublattice potential, and then, by analyzing the Ruderman–Kittel–Kasuya–Yoshida (RKKY) interaction in these lattice structures, the magnetic ground states of 1D-BTKLs in the presence of two magnetic adatoms are evaluated. It is found that the 1D channels of BTKL show different electronic and magnetic behaviors due to different values of the hopping integrals and spin–orbit couplings. Two important salient features of 1D-BTKLs are the presence of flatbands in their band structures as well as the emergence of the RKKY plateau vs the Fermi energy. To the best of our knowledge, it is the first time that the RKKY plateau is systematically reported and as we will see this idea has been advocated forcefully. It was shown that both the width and location of the magnetization plateaus could be controlled through variation of the staggered potential and the Fermi energy as well as the spatial configuration of the magnetic impurities, enabling a variety of electromagnetic devices to be produced. The other fascinating feature of the present study is the magnetic susceptibility discontinuity, named as magnetization jump, which accompanies with the discontinuity in the magnetization curves. We believe that our results provide significant insights into designing further experiments to search for the realization of the flatbands and magnetization plateau phases in spintronics and pseudospin electronic devices based on TKLs.
Effect of isotope substitution on the Fermi resonance and vibrational lifetime of unnatural amino acids modified with IR probe: A 2D-IR and pump-probe study of 4-azido-L-phenyl alanine
Authors: Park Jun Young , Mondal Saptarsi , Kwon Hyeok-Jun , Sahu Prabhat Kumar , Han Hogyu , Kwak Kyungwon , Cho Minhaeng
Published: October 2020

The infrared (IR) probe often suffers from an unexpected complex absorption profile due to the Fermi resonance and short vibrational lifetime, which restricts the application of time-resolved IR spectroscopy to investigate the site-specific structural dynamics of the protein. Researchers have found that isotope substitution to the IR probe not only removes the Fermi resonance but also extends the dynamic observation window with a prolonged vibrational lifetime. This method has been successfully applied to modify the vibrational properties of many IR probes for time-resolved spectroscopy and imaging. In this study, the effect of isotope substitution (15N) on the vibrational properties of the azide stretching band in 4-azido-L-phenylalanine has been investigated using ultrafast pump-probe and 2D-IR spectroscopy. In contrast to the earlier reports, it has been observed that the Fermi resonance remains unchanged even after isotope substitution, and there is very little change in the vibrational relaxation dynamics as well. Anharmonic frequency analysis reveals that the α-N atom of N3 is being shared between the two transitions participating in the Fermi resonance and gets affected similarly due to isotope labeling. Hence, this study unveils the specific circumstance at which the isotope labeling strategy may not be successful in eliminating the Fermi resonance band and explains the molecular origin behind it. This study also suggests definitive approaches on how to overcome the limitations related to the Fermi resonance to extend the development and application of this IR probe for biological research.
How is structural inequality made fair in a meritocratic education system?
Authors: Talib Nadira
Published: October 2020

This paper examines how, within the context of meritocracy, a highly differentiated education system can coexist
with assertions of equal opportunity. Drawing on the example of Singapore’s education policy texts from 1991 to 2012, the paper
exemplifies and expands the analytical potential of a micro-meso-macro movements framework with which to critically engage the
discursive role of neo-liberal metaphors in ameliorating the tension of providing ‘equal opportunities’ between students who will
undertake the university pathway and those who will have to undergo vocational training. Based on the interconnected discourses of
opportunity-choice and opportunity-skills through a more flexible system, the analytical
development of these two simultaneous sub micro-meso-macro movements demonstrates how the playing field is
levelled, and competition for society’s occupations and academic progression is fair even for Vocational and Industrial Training
Board Act (VITB) trainees.
Definiteness Marking from Evaluative Morphology in Balochi: Internal Variation and Diachronic Pathway
Authors: Nourzaei Maryam
Published: October 2020

This paper investigates the usage and frequency of what is referred to as K-suffixes in three Balochi dialects, namely Koroshi, Coastal and Sistani Balochi. It shows that K-suffixes are most likely the reflexes of earlier evaluative morphology, traditionally termed “diminutives,” and are characterized by a high degree of multi-functionality. While in Coastal and Sistani Balochi evaluative functions continue to dominate, they have been largely lost in Koroshi Balochi, and the suffix is now used to indicate definiteness. The development appears to have been spearheaded by female speakers, and its frequency is also dependent on genre and speech situation. Data is taken from an extensive corpus of spoken Balochi narratives and from a questionnaire with thirty-six speakers. The results suggest that evaluative morphology can develop into definiteness marking, with the development passing over a stage of combination with deictic markers. The paper concludes that the development of definiteness marking can proceed down a pathway that is distinct from the one normally assumed for demonstrative-based definite marking, though the endpoint may be similar. This is the first detailed documentation of this process for any Iranian language, and one of the few well-documented cases of a non-demonstrative origin of definiteness marking worldwide.
Sustained androgen receptor signaling is a determinant of melanoma cell growth potential and tumorigenesis
Authors: Ma Min , Ghosh Soumitra , Tavernari Daniele , Katarkar Atul , Clocchiatti Andrea , Mazzeo Luigi , Samarkina Anastasia , Epiney Justine , Yu Yi-Ru , Ho Ping-Chih , Levesque Mitchell P. , Özdemir Berna C. , Ciriello Giovanni , Dummer Reinhard , Dotto G. Paolo
Published: October 2020

Melanoma susceptibility differs significantly in male versus female populations. Low levels of androgen receptor (AR) in melanocytes of the two sexes are accompanied by heterogeneous expression at various stages of the disease. Irrespective of expression levels, genetic and pharmacological suppression of AR activity in melanoma cells blunts proliferation and induces senescence, while increased AR expression or activation exert opposite effects. AR down-modulation elicits a shared gene expression signature associated with better patient survival, related to interferon and cytokine signaling and DNA damage/repair. AR loss leads to dsDNA breakage, cytoplasmic leakage, and STING activation, with AR anchoring the DNA repair proteins Ku70/Ku80 to RNA Pol II and preventing RNA Pol II–associated DNA damage. AR down-modulation or pharmacological inhibition suppresses melanomagenesis, with increased intratumoral infiltration of macrophages and, in an immune-competent mouse model, cytotoxic T cells. AR provides an attractive target for improved management of melanoma independent of patient sex.
Polarization converter of single photons on a two-dimensional quantum dot in an optical microresonator
Authors: Tsukanov A V , Kateev I Yu
Published: October 2020

A polarization conversion of a single photon using a semiconductor quantum dot (QD) coupling to a two-mode optical microresonator (MR) is studied. The rotation angle of the polarization vector depends on the orientation of QD axes with respect to MR ones, parameters of the system, and a conversion regime. A nanostructure based on a two-dimensional photonic crystal coupling to a single-electron QD is considered as the possible converter design. It is shown that this structure can also act as a beam splitter and perform the quantum operation NOT on a spatial photon qubit.
Novel CMOS image sensor pixel to improve charge transfer speed and efficiency by overlapping gate and temporary storage diffusing node*
Authors: Yang Cui , Peng Guo-Liang , Mao Wei , Zheng Xue-Feng , Wang Chong , Zhang Jin-Cheng , Hao Yue
Published: October 2020

A novel CMOS image sensor (CIS) pinned photodiode (PPD) pixel, named as O-T pixel, is proposed and investigated by TCAD simulations. Compared with the conventional PPD pixel, the proposed pixel features the overlapping gate (OG) and the temporary storage diffusing (TSD) region, based on which the several-nanosecond-level charge transfer could be achieved and the complete charge transfer from the PPD to the floating node (FD) could be realized. And systematic analyses of the influence of the doping conditions of the proposed processes, the OG length, and the photodiode length on the transfer performances of the proposed pixel are conducted. Optimized simulation results show that the total charge transfer time could reach about 5.862 ns from the photodiode to the sensed node and the corresponding charge transfer efficiency could reach as high as 99.995% in the proposed pixel with 10 μm long photodiode and 2.22 μm long OG. These results demonstrate a great potential of the proposed pixel in high-speed applications.
Multi-scale molecular dynamics simulations and applications on mechanosensitive proteins of integrins*
Authors: Lü Shouqin , Ding Qihan , Zhang Mingkun , Long Mian
Published: October 2020

Molecular dynamics simulation (MDS) is a powerful technology for investigating evolution dynamics of target proteins, and it is used widely in various fields from materials to biology. This mini-review introduced the principles, main preforming procedures, and advances of MDS, as well as its applications on the studies of conformational and allosteric dynamics of proteins especially on that of the mechanosensitive integrins. Future perspectives were also proposed. This review could provide clues in understanding the potentiality of MD simulations in structure–function relationship investigation of biological proteins.
Vertical GaN Shottky barrier diode with thermally stable TiN anode*
Authors: Liu Da-Ping , Li Xiao-Bo , Pu Tao-Fei , Li Liu-An , Cheng Shao-Heng , Wang Qi-Liang
Published: October 2020

Vertical GaN Schottky barrier diodes with TiN anodes were fabricated to investigate the electrical performance. The turn-on voltage and specific on-resistance of diodes are deduced to be approximately 0.41 V and 0.98 mΩ⋅cm2, respectively. The current-voltage curves show rectifying characteristics under different temperatures from 25 °C to 200 °C, implying a good thermal stability of TiN/GaN contact. The low-frequency noise follows a 1/f behavior due to the multiple traps and/or barrier inhomogeneous at TiN/GaN interface. The trapping/de-trapping between traps and Fermi level causes the slight capacitance dispersion under reverse voltage.
Glassy dynamics from generalized mode-coupling theory: existence and uniqueness of solutions for hierarchically coupled integro-differential equations
Authors: Biezemans Rutger A , Ciarella Simone , Çaylak Onur , Baumeier Björn , Janssen Liesbeth M C
Published: October 2020

Generalized mode-coupling theory (GMCT) is a first-principles-based and systematically correctable framework to predict the complex relaxation dynamics of glass-forming materials. The formal theory amounts to a hierarchy of infinitely many coupled integro-differential equations, which may be approximated using a suitable finite-order closure relation. Although previous studies have suggested that finite-order GMCT leads to well-defined solutions, and that the hierarchy converges as the closure level increases, no rigorous and general result in this direction is known. Here we unambiguously establish the existence and uniqueness of solutions to generic, schematic GMCT hierarchies that are closed at arbitrary finite order. We consider two types of commonly invoked closure approximations, namely mean-field and exponential closures. We also distinguish explicitly between overdamped and underdamped glassy dynamics, corresponding to hierarchies of first-order and second-order integro-differential equations, respectively. We find that truncated GMCT hierarchies closed under an exponential closure conform to previously developed mathematical theories, both in the overdamped and underdamped case, such that the existence of a unique solution can be readily inferred. Self-consistent mean-field closures, however, of which the well-known standard-MCT closure approximation is a special case, warrant additional arguments for mathematical rigor. We demonstrate that the existence of a priori bounds on the solution is sufficient to also prove that unique solutions exist for such self-consistent hierarchies. To complete our analysis, we present simple arguments to show that these a priori bounds must exist, motivated by the physical interpretation of the GMCT solutions as density correlation functions. Overall, our work contributes to the theoretical justification of GMCT for studies of the glass transition, placing this hierarchical framework on a firmer mathematical footing.
Preparation of boron-doped diamond modified by bimetal nickel and zinc
Authors: Putri Y M T A , Jiwanti P K , Irkham  , Gunlazuardi J , Einaga Y , Ivandini T A
Published: October 2020

Nickel has been known as a good catalyst due to its high activity and stability, but the potential formation of NiOOH is quite high. In this work, zinc together with nickel was used to modify the surface of boron-doped diamond (BDD) to lower the formation potential of NiOOH. Electro-deposition (multi pulse amperometry) technique was applied at a potential of -1.6 V for 600 s. The prepared electrode (NiZn-BDD) characterized using SEM-EDX and XPS shows that both nickel and zinc were deposited homogenously on the surface of BDD with the ratio of 1:2 for nickel:zinc.
Preparation and characterization of β-Cyclodextrin/Fe3O4 nanocomposite
Authors: Saepudin E , Willyam S J , Irkham  , Ivandini T A
Published: October 2020

Host-guest mechanism and the formation of inclusion complexes between β-cyclodextrin (BCD) with cholesterol as the electroactive species can indicate a non-enzymatic sensor of cholesterol. For that purpose, in this study, BCD functionalized on Fe3O4 magnetic nanoparticles (MNPs) were synthesized by a simple co-precipitation method of Fe2+ and Fe3+ solutions under alkaline conditions for an easy separation. BCD/MNPs nanocomposite were characterized by XRD, TEM, and FTIR. The average size of MNPs and BCD/MNPs were 16.22 nm and 9.80 nm, respectively showed by both XRD and TEM. FTIR result also indicates that BCD/MNPs was successfully formed.
High stable Hb/Pt/BDD electrode for determining acrylamide in coffee samples
Authors: Wulandari R , Saepudin E , Ivandini T A
Published: October 2020

A novel electrochemical hemoglobin-platinum-modified boron-doped diamond (Hb/Pt/BDD) biosensor was developed for the detection of acrylamide (AA) in coffee samples. The Hb-Pt-BDD electrode was characterized by cyclic voltammetry (CV), scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectrons (XPS). The cyclic voltammetry of Hb-Pt-BDD in 0.2 M sodium acetate buffer (ABS, pH 4.8) containing acrylamide in the concentration range of 0.00213 to 0.00711 ppb, showed linear responses with a detection limit of 0.00155 ppb. The excellent stability of the prepared Pt-modified BDD was proven through the Pt-BDD reusability by removing the Hb adduct without eliminating Pt on the BDD surface. Finally, employing the biosensor was proposed to determine AA in 1 g of coffee showed the AA content of 15.55 ppb. The result was comparable with the reference method using liquid chromatography-tandem mass spectrometry (LC-MS/MS).
Copper oxide modification to improve the photocatalytic activity of titanium dioxide nanoparticles: P25 versus P90
Authors: Yuliati L , Hasan N , Lintang H O
Published: October 2020

Titanium dioxide (TiO2) has been recognized as one of the most active photocatalysts for organic pollutant degradation under ultraviolet (UV) light irradiation. In order to reduce the fast charge recombination in the TiO2, various methods have been investigated, including the addition of metal oxide co-catalysts. Owing to the characteristic of the nanoparticles, the modification of nanoparticles involving heat treatment is still a challenging task. In this work, two commercial TiO2nanoparticles, namely P25 and P90 (Evonik), were modified by copper oxides (CuO) and the photocatalytic activity was evaluated for degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) under UV light. The CuO/P25 and CuO/P90 samples with various loading amounts (0.1, 0.25, 0.5 and 1.0 wt %) were prepared by precipitation of copper(II) nitrate to the P25 or P90 nanoparticles at pH of 9, followed by calcination at 573 K. X-ray diffraction (XRD) patterns indicated that all samples have the characteristics of both anatase and rutile phases. While the addition of CuO did not much affect the structure, crystallite size, and anatase-rutile ratio of the P25 and P90 nanoparticles, the presence of the copper species was confirmed by the scanning electron microscopy (SEM) equipped with the energy-dispersive X-ray (EDX) spectroscopy. Moreover, fluorescence spectra also showed that the CuO quenched the emission intensity of both the P25 and P90 nanoparticles, suggesting the successful decrease of the charge recombination in the TiO2nanoparticles. Photocatalytic activity tests showed that the P25 and P90 gave percentage degradation of 90 and 47 %, respectively, after a 1-hour reaction. Even though not much improvement was observed for P25 TiO2nanoparticle after the CuO addition (92 %), the activity of P90 nanoparticle was enhanced from 47 % to 86–87 % with the CuO addition of 0.1–0.25 wt %. This study demonstrated that it is feasible to improve the photocatalytic activity of TiO2commercial nanoparticles, in this case, the P90, by surface modification using the CuO.
One-pot four-component synthesis of phenazine derivative using 2-hydroxy-1,4-naphthoquinone
Authors: Cahyana A H , Nazhifah N , Liandi A R
Published: October 2020

Phenazine is one of the most important organic compounds because of its various biological activities. This study aims to synthesize the phenazine derivatives compound using 2-hydroxy-1,4-naphthoquinone (lawsone) with a one-pot four-component method.Phenazine derivative that had been successfully synthesized was carried out by reacting four reactants at once in one flask with the same mole ratio. The reaction occurred between lawsone, o-phenylenediamine, benzaldehyde, and malononitrile. Characterization of the synthesized products was confirmed using FT-IR, UV-Vis Spectrophotometer, and LC-MS. The results of the analysis using several of these instruments obtained one compound, namely 3-amino-2-cyano-1-phenyl-1H-benzo[a]pyrano[2,3-c]phenazine. The reaction conditions were carried out at 50°C for 6 h in ethanol with unassisted catalysts and obtained a product yield of 45%.
Application of MoS2/reduced graphene oxide for photocatalytic degradation of rhodamine B in water environment
Authors: Trang P T T , Tam T T , Vien V , Lien N H
Published: October 2020

In this study, MoS2 was composited with RGO (the reduced form of graphene oxide) for enhancing the photocatalytic degradation of RhB in aqueous solution by applying visible light irradiation. A new approach to synthesize graphene was applied by reduction of graphene oxide using ascorbic acid. Factors affecting the photocatalytic degradation including pH, initial rhodamine B concentration, light source intensity and quencher existence were investigated. The results showed that MoS2/RGO composite exhibited better photocatalytic activity in the degradation of RhB (with a conversion of 80 %) compared to pure MoS2 (with a conversion of 30.8 %) under visible light irradiation. The higher photocatalytic performance of MoS2/RGO was found in slight acidic environment. Among the tested free radical killers, ammonium oxalate revealed the most significant effect on the photocatalytic degradation of RhB.This research also indicated that MoS2/RGO composite can be considered as a potential catalyst for the degradation of persistent organic dyes in wastewater.
Synthesis of macroanion [α-SiW12O40]4- as pillaring agents to layered double hydroxide Zinc-M3+
Authors: Silaen L , Azmi M F , Palapa N R , Mohadi R , Elfita  , Lesbani A
Published: October 2020

Polyoxometalate intercalated layered double hydroxide was prepared by ion exchange of zinc-aluminum and zinc-chromium LDH with macro anion [α-SiW12O40]4- at room temperature. The structural characterization was conducted with XRD, adsorption and desorption N2 by BET method and FTIR analyses. An interlayer space of zinc-aluminum and zinc-chromium was increased after the intercalation process. The interlayer space at reflection (003) shows zinc-aluminum and zinc-chromium intercalated LDH is 10.36 Å and 10.49 Å from 7.57 Å and 7.68 Å, respectively. The value of surface area zinc-aluminum and zinc-chromium before intercalation are 2.10 m2/g and 31.63 m2/g and increase after intercalation to 14.0422 m2/g and 128.87 m2/g, respectively. This phenom identifies that both LDH has a great reflexibility based on anion in the interlayer.
Investigation of metalloporphyrin compound in maltenes of duri crude oil
Authors: Vinny  , Yulizar Y , Ekananda R , Kurniawaty I , Haerudin H , Apriandanu D O B
Published: October 2020

Metalloporphyrin is one of the compounds that could potentially cause deactivation of catalysts in the process of catalytic cracking and hydrotreating. Knowledge of the structure of metalloporphyrin can be used as the basic information in overcoming the problem of catalyst poisoning. This work is performed to identify metalloporphyrins in the maltenes fraction of Duri crude oil. The low content of asphaltenes in Duri crude oil with a fractional weight of 0.79 %, allows a high level of metalloporphyrin in the fraction of maltenes which has a fractional weight of 82.73 %. Metalloporphyrin in the maltenes derivate fraction, saturates, aromatics, and resin were separated using column chromatography. Saturates, aromatics and resins have fractional weight of 49.75; 34.92; and 15.33 %, respectively. Only resin contained metalloporphyrin based on the analysis of UV-Vis spectrophotometer and Fourier-transform infrared spectroscopy (FT-IR), thus metalloporphyrins in resin was further separated into fractions by column chromatography. The result of UV-Vis spectrophotometer analysis for resin separation showed an absorbance peak of metalloporphyrin at 480–700 nm, while FT-IR analysis showed the presence of pyrrole group as porphyrin base framework with vibrational region at 400–1100 cm−1 The results of micro plasma-atomic emission spectrometer (MP-AES) analysis showed the presence of Fe, Ni, and V metals content. The liquid chromatography-mass spectrometer (LC-MS) analysis showed the molecular structure of the obtained compound was C33H34N4VO2. According to the results, metalloporphyrins presented in the maltenes fraction of Duri crude oil was vanadyl porphyrin.
In vivo study of 8-OHdG as a biomarker DNA damage by combining the exposure of nonyl phenol and copper using ELISA technique
Authors: Budiawan  , Rizkita A D , Handayani S , Dani I C
Published: October 2020

Nonylphenol (NP) is an environmental contaminants produced by alkylphenol ethoxylates which is non-ionic surfactant. NP has recently been found in foods derived from antioxidant hydrolysis of tris nonylphenyl phosphite which is used as a heat stabilizer in the manufacture of polymer food packaging materials, such as styrene, vinyl polymer, rubber and polyolefins. Copper (Cu) is a redox metal which in the normal dose is an essential mineral that needed by the body, but excess Cu will cause damage in some organs. Both NP and Cu can produce OH radicals in the body, which means that OH radicals will potentially attack DNA and thus form a biomarker of DNA damage such as 8-OHdG. This study of DNA adducts of 8-OHdG formation due to NP as a xenobiotic and Cu as metals. In this research, the eight-month-old Sprague Dawly rats weighing 200 −300 g were randomly divided into three groups (Control, Cu, NP, and NP + Cu, n = 5). The tested rats were orally treated every 24 h for 28 days. Finally, the collected plasma was tested using ELISA technique to study the 8-OHdG content. Based on the results, it was shown that both NP and Cu metals could trigger the formation of 8-OHdG. The highest concentration of 8-OHdG formed was the exposure group of NP + Cu in day 14 with a concentration of 1.3412 ng/mL.
Cs-137 radionuclide bioaccumulation study in gold fish (Cyprinus carpio) through freshwater path with variations of potassium ion concentration (K+)
Authors: Baramanda T A , Budiawan  , Bakri R , Suseno H
Published: October 2020

Few anthropogenic radionuclides like Cs-137 are difficult to detect. It needs a method to evaluate the environment quality based on molecular network of an organism exposed to the radionuclide arises, and the said method is called Biomonitoring. In this study, biokinetic experiment is conducted with the determination of Concentration Factor (CF) and Bioaccumulation Factor values of Cs-137 in goldfish (Cyprinus carpio) by means of freshwater influenced by its aquatic environment condition, which is potassium ion concentration (K+). CF value of Cs-137 concentration in Cyprinus carpio after the end accumulation in media conditioned with variation of potassium concentration 2.5; 5; 7.5 and 10 ppm, respectively are 2.762; 2.645; 2.637; 2.568 mL.g−1 and Bioconcentration Factor (BCF) for variation of K+ ion concentration 2.5; 5; 7.5 and 10 ppm, respectively are 1.32; 2.12; 1.77; 2.07 ml.g−1. Based on those values, goldfish (Cyprinus carpio) cannot be categorized as bioindicator for Cs-137.
The localized surface plasmon resonance on noble metal-semiconductor: Au nanosphere-ZnO nanorod
Authors: Sujak M , Djuhana D
Published: October 2020

In this work, we have investigated the localized surface plasmon resonance of metal-semiconductor model. The raw materials are gold nanosphere (Au-NP) and ZnO nanorod (ZnO-NR). The nanoparticles were surrounded by air with refractive index constant (1.0+0i). Moreover, the diameter and aspect ratio of Au-NP and ZnO-NR were 40 nm and 4, respectively. Then, we designed the nanoparticle in two different configurations. First, Au-NP was placed at the sides of ZnO-NR and second, Au-NP was placed at the tip of nanorod. Next, we varied the gap-distance among them from 0 nm to 40 nm with 10 nm increment. The photon wavelength used were from 300 nm to 1200 nm within two different excitations (transverse and longitudinal excitation). Furthermore, our result suggests that on the longitudinal excitation, when the gap-distance increases, the resonance peak of second configuration remains at constant value and the intensity significantly decreases compared to the first configuration. However, on the transverse excitation, the first configuration has a high intensity and the resonance peaks is slightly red-shifted. In addition, based on the near-field mapping which reflects the energy density of electromagnetic field by LSPR, the LSPR of Au-NP stands to aid the exciton production to enhance the photocatalytic activity.
The diameter effect on the magnetization switching time of sphere-shaped ferromagnets using micromagnetic approach
Authors: Kurniawan C , Widodo A T , Djuhana D
Published: October 2020

In this work, the magnetization switching time has been studied as the diameter variation of sphere-shaped ferromagnets by means of micromagnetic simulation. Some ferromagnetic elements such as cobalt, iron, nickel, and permalloy were numerically simulated with diameter size variation from 50 nm to 100 nm. The micromagnetic simulation was performed by public software Object Oriented Micromagnetic Framework (OOMMF) based on the Landau-Lifshitz-Gilbert (LLG) equation. The ferromagnetic nano-sphere was induced by the quasi-static magnetic field to observe its magnetization response. Generally, it is observed that the switching time increases as the diameter size increases on the ferromagnetic elements. However, the switching time are relatively insensitive as the diameter increases in the Cobalt element for the diameter range from 60 nm to 90 nm. This behavior is contributed to the distribution of magnetization easy axis on the ferromagnetic elements. The understanding of domain structures during magnetization switching process is important in the development of nano-patterned magnetic memory storage.
The growth rate and chlorophyll content of water hyacinth under different type of water sources
Authors: Hasibuan A A , Yuniati R , Wardhana W
Published: October 2020

Agathis Lake is one of the six lakes around Universitas Indonesia, Depok. This lake is a water body whose water quality has been damaged due to pollution from domestic and industrial waste around Beji area, Depok. Water hyacinth ( Eichhornia crassipes (Mart.) Solms.) is a plant that has the ability to absorb contaminants in aquatic environment. This study was designed to determine the growth rate and chlorophyll content of water hyacinth under different type of water sources as growing media. These two physiological parameters are used to determine whether the contaminants contained in the Lake Agathis interfere the growth of water hyacinth. The research was conducted at the greenhouse of Departement of Biology, FMIPA, Universitas Indonesia for six days, after 1-week acclimatization by culturing water hyacinth in 30 L capacity plastic tanks. Sixteen plants of water hyacinth, each of approximately 28–31 g wet weight, were placed into four plastic tanks. Two tanks filled with 10 L tap water, and another two filled with 10 L lake water (Agathis Lake).The results showed that the Relative Growth Rate (RGR) of water hyacinth in the tap water was higher than the lake water. The chlorophyll content of water hyacinth cultured in the lake water was higher than the plant cultured in tap water.
Acetylation of curcuminoids extract from Turmeric Rhizomes (Curcuma longa) as antibacterial compounds against S. aureus and E. coli
Authors: Fadhlurrahma A , Saepudin E , Rahayu D U C
Published: October 2020

Curcuminoid are active compounds of turmeric rhizome that widely known to have antibacterial activities. The low activity of curcuminoid as antimicrobial may be due to the presence of phenol moiety and hence it has low lipophilicity and low bioavailability. Antibacterial activities of curcuminoid derivatives may be improved by increasing their lipophilicity, one of which is replacing the hydrogen atom on the phenol groups with acetyl group by acetylation. The curcuminoids were extracted from turmeric rhizomes by Soxhlet method yielded of 10.24 %. This curcuminoids were structurally modified by acetylation using acetic anhydride with Ni/SiO2 catalyst. The products were separated through column chromatography then characterized using thin layer chromatography (TLC), UV-Vis, FTIR and LC-MS spectrometers. The results showed that the best condition of this reaction found when 15 % (w/w) catalyst was used with product conversion of 90.44 %. Diameter of inhibitory zone of acetyl curcuminoid derivatives showed the highest antibacterial activity at a concentration of 500 ppm against S. aureus of 18 mm and against E. coli of 13 mm. On the other hand, at the same concentration, the curcuminoid had inhibitory zone of 7.5 mm and 8 mm against S. aureus and E. coli, respectively. Therefore, the acetylation of curcuminoids has increased their antibacterial activities against Gram positive bacteria S. aureus up to 2.4 fold, while against Gram negative bacteria E. coli by only 1.6 fold.
The capacity of water hyacinth as biofilter and bioaccumulator based on its size
Authors: Elizabeth J , Yuniati R , Wardhana W
Published: October 2020

Nowadays, aquatic environmental contamination caused by human activities is increasing. One of several types of contaminants is heavy metal. Water hyacinth,Eichhornia crassipes(Mart.) Solms. is an aquatic plant that has been known to have a capacity to absorb heavy metals through its roots. Previous study reported that water hyacinth can reduce the amount of the suspended solid in the water. The objective of this study is to evaluate the performance of three sizes of water hyacinth in filtering the suspended solid from turbid water. The experiment was conducted in a greenhouse over a period of seven days on August 2019. The plant material was obtained from water body in Sawangan, Depok area. We used fifteen plants which categorized into three sizes of water hyacinth, i.e. small, medium and large. Those plants were first acclimatized for a period of seven days in tap water without addition of nutrients. For the next seven days, the water hyacinths were transferred to a fiberglass rectangular fish tank filled with 50 L water from Situ (Lake) Agathis, Depok. From the results, it was found that the accumulation capacity of lead (Pb), cadmium (Cd) and copper (Cu) by water hyacinth decreased by the increase of plant size. Another result showed that compared to leaves and stems, roots accumulate more heavy metals. Under seven days of growing period, all the fifteen water hyacinth plants can reduce the total dissolved solids (TDS) from 261 ppm to 204 ppm, and total suspended solids (TSS) from 0.0449 ppm to 0.0151 ppm.
Systematic investigation into mechanical strength, pore structure and microstructure of high performance concrete incorporating nano-hybrids
Authors: Morsy M. , Shoukry H. , Mokhtar M.M. , Taha N. A. , Morsy M. S.
Published: October 2020

In this study, high performance concrete (HPC) containing two types of nanoparticles: carbon nano tubes (CNTs) and nano silica (NS) and hybrid nanoparticles (CNTs + NS) were prepared. The compressive strength, phase composition, pore size distribution, surface area, surface morphology and microstructural characteristics were investigated at 7 and 28 days of hydration. In addition, the combined effect of CNTs and silica fume (SF) on the properties of concrete has been investigated in this study for comparison reasons. The results indicated that, all kinds of the utilized nanoparticles provided an enhancement in the compressive strength of the hardened concrete at early and later ages of hydration. Furthermore, Thermogravimetric analysis (TGA) patterns revealed no great difference in the hydration degree of cement with the addition of CNTs. However, Due to its large specific surface area and the pozzolanic activity, CNTs+NS nanohybrid showed the best acceleration efficiency. The concrete containing CNTs+NS nanohybrid exhibited the highest improvement in compressive strength. The pozzolanic reaction induced by NS and silica fume (SF) led to remarkable increase in the surface area and the nanoporosity/gel pores assigned to calcium silicate hydrate (CSH) phase. The SEM analysis showed that, CNTs resulting in bridging nano-size and micro-size pores or gaps within cement hydrates; however, SF and NS are more efficient in filling the pores and gaps between the hydration products and providing more compact microstructure.
Attenuation Effectiveness of Double Phase Stainless Steel Alloys for Fusion Reactor System
Authors: Ali Noha M. , Saeed Aly , El Shazly R. M. , Al-Fiki S. A. , Eissa M. M. , El-kameesy S. U.
Published: October 2020

Aluminium, tungsten and aluminium - tungsten ferritic stainless-steel alloys were developed and produced using 30 kg pilot plant induction furnace of medium frequency at the same conditions to be applied in nuclear reactor shielding material. Higher hardness, ultimate strength, and ultimate tensile strength are appeared in the developed alloys. Aluminium stainless-steel elongation had lower values. Total slow neutrons, neutrons > 10 keV, and slow neutrons of aluminium-tungsten based ferritic stainless steel alloys which carried out using 241Am-Be neutron source as well as a wide range up to 1400 keV energies of gamma rays, which emitted from Co-60, Cs-137 and Eu-152, were used by means of sodium iodide (Tl) detector and studied using the XCOM program. Results showed that all studied stainless-steel alloys own a converge values of neutron macroscopic cross sections (Σ, cm“1). Moreover, there is no significant variation of the value of mass attenuation coefficients (σ, cm2/g) for the studied alloys. Good agreement between both experimental and calculated results of mass attenuation coefficients was achieved. A new composition for several nuclear applications such as, nuclear shielding applications were achieved.
Tuning the Co/Sr stoichiometry of SrCoO2.5 thin films by RHEED assisted MBEgrowth
Authors: Schöffmann P , Pütter S , Schubert J , Zander W , Barthel J , Zakalek P , Waschk M , Heller R , Brückel T
Published: October 2020

Strontium cobaltite (SrCoO2.5+δ
, SCO) is a fascinating material because of its topotactic structural phase transition caused by a change in oxygen stoichiometry. In the brownmillerite phase (δ = 0) it is an insulating antiferromagnet whereas in the perovskite phase (δ = 0.5) it is a conducting ferromagnet. In contrast, the impact of the varying Co/Sr stoichiometry on the structure has not yet been studied in SCO thin films. Using molecular beam epitaxy we have fabricated SCO thin films of varying Co/Sr stoichiometry. Films with Co excess exhibit a brownmillerite crystal structure with CoO precipitates within the thin film and on the surface. Co deficient films are amorphous. Only for 1:1 stoichiometry a pure brownmillerite structure is present. We find a clear dependence of the Reflection High Energy Electron Diffraction (RHEED) pattern of these thin films on the stoichiometry. Interestingly, RHEED is very sensitive to a Co excess of less than 12% while x-ray diffraction fails to reveal that difference. Hence, using RHEED, the stoichiometry of SCO can be evaluated and tuned in-situ to a high degree of precision, which allows for a quick adjustment of the growth parameters during a sample series.
Stability study of iodinated reduced graphene oxide and its application in self-assembled Al/Bi2O3 nanothermite composites
Authors: Wang Anqi , Bok Sangho , Mathai Cherian Joseph , Gangopadhyay Keshab , McFarland Jacob , Maschmann Matthew R , Gangopadhyay Shubhra
Published: October 2020

The direct reduction of graphene oxide (GO) by hydroiodic acid is an established method to produce iodine functionalized reduced GO (I-rGO). However, the stability of the iodine species within I-rGO upon heating and dispersing into different solvents, as required for many applications, has not been examined. Herein we examined the stability of I-rGO and utilized it to promote self-assembled nanoenergetic composites. I-rGO intercalated with polyiodide was found to be unstable at elevated temperature and when dispersed in organic solvents. The I-rGO exhibited excellent dispersion in dimethylformamide but resulted in a loss of iodine content as exfoliation released weakly-bound intercalated iodine species. The dispersed I-rGO was utilized as a scaffold to self-assemble I-rGO/Al and I-rGO/Al/Bi2O3 nanoenergetic composites. The I-rGO both prevented the phase separation of Al and Bi2O3 particles and provided a source for reactive iodine to etch the alumina shell surrounding Al fuel nanoparticles. Differential scanning calorimetry showed that the use of the I-rGO assembly template reduced the temperature of initiation and peak reaction and produced 70% greater energy release than randomly mixed Al/Bi2O3 nanoenergetic powder. In fact, 95% of the exothermal energy released by the reaction occurred while Al was in the solid state, suggesting that the reaction between free iodine and alumina was significant enough to greatly reduce the diffusion barrier between solid Al fuel and surrounding oxidizer. Further, the underlying conductive I-rGO scaffold reduces electrostatic discharge sensitivity of the nanoenergetic composite by almost four orders of magnitude.
Cdc1p is a Golgi-localized glycosylphosphatidylinositol-anchored protein remodelase
Authors: Yang Gege , Banfield David K.
Published: October 2020

Discrepancies in the prevailing role of the GPI-AP remodelase Cdc1p prompted us to reexamine the localization of this protein. Cdc1p is a Golgi-restricted membrane protein, rather than localized to the ER. Removal of ethanolamine phosphate appears to function in quality control surveillance of nascent GPI-APs in the ER and Golgi in yeast cells.
An International LGBT Movement
Authors: Thoreson Ryan
Published: October 2020

As lesbian, gay, bisexual, and transgender (LGBT) advocates around the globe have fought to gain rights and recognition, their shared endeavors and coordinated activism have given rise to an international LGBT movement. Over the past century, advocates around the world have recognized common aims and collaborated in formal and informal ways to advance the broader cause of sexual equality worldwide. Advocates in different contexts have often connected their struggles, borrowing concepts and strategies from one another and campaigning together in regional and international forums. In doing so, they have pressed for goals as diverse as the decriminalization of sexual activity; recognition of same-sex partnerships and rainbow families; bodily autonomy and recognition for transgender and intersex people; nondiscrimination protections; and acceptance by families, faith communities, and the public at large. At times, the international LGBT movement—or, to be more accurate, LGBT movements—have used tactics as diverse as public education, lobbying and legislative campaigns, litigation, and direct action to achieve their aims. The result has been a gradual shift toward recognizing LGBT rights globally, with these rights gaining traction in formal law and policy as well as in public opinion and the agendas of activists working for human rights and social justice. The movement’s aims have also broadened, being attentive to new issues and drawing common cause with other campaigns for bodily autonomy and equal rights. At the same time, gains have triggered ferocious backlash, both against LGBT rights and against broader efforts to promote comprehensive sexuality education, access to abortion, the decriminalization of sex work, and other sexual rights. Understanding this advocacy requires consideration of important milestones in global LGBT organizing; how LGBT rights have been taken up as human rights by domestic, regional, and international bodies; and some of the main challenges that LGBT advocates have faced in contexts around the globe.
Centralization and Decentralization: Compatible Governance Concepts and Practices
Authors: Witesman Eva M.
Published: October 2020

The extent to which governance structures are centralized or decentralized is a key consideration for public administrators. While centralization and decentralization seem to represent opposite approaches to the structure of public organizations, the two frequently co-exist simultaneously in what is alternately deemed a comfortable coexistence or a paradoxical tension. Public institution reform efforts may call for increased centralizing forces (such as hierarchy, unification, and governance) or decentralizing ones (such as marketization, devolution of power, deconcentration, and diversification).

Public administrators calling for structural reform are often driven toward either centralization or decentralization by particular sets of public values. Values such as accountability, power, and efficiency favor centralized governance, while values such as responsiveness, engagement, and innovation favor decentralization. Thus, the design of public administration structures and processes frequently exist as an expression of value-based norms. Both centralization and decentralization are associated with distinct advantages for achieving specific public value goals. Conversely, each approach has unique weaknesses that create opportunities for corruption.

The pursuit of public value goals and the avoidance of corruption are two primary drivers that motivate structural reform. While structural reforms may be viewed as swings of a pendulum between two extreme ideal states (fully centralized or fully decentralized), a growing consensus in the scholarship suggests that centralized and decentralized structures are internally compatible and complementary. In other words, both centralized and decentralized structures frequently co-exist within the same institutions, often creating a dynamic tension between values. This creates an increasingly complex structural paradigm for the expression of public values. The result is that many governance structures appear to be evolving toward new models in which elements of both centralized and decentralized control are observed simultaneously.
Conscription and the Politics of Military Recruitment
Authors: Toronto Nathan W. , Cohn Lindsay P.
Published: October 2020

There is more to conscription than the presence or absence of conscripts in a military force. A brief survey of the history of military recruitment suggests that economics, threat, and political heritage go a long way toward explaining why and how states recruit manpower and prepare that manpower for war. Understanding the sources and implications of different types of military recruitment, and how trends in military recruitment change over time, is essential for understanding conscription now and in the future.

The French Revolution is often regarded as a turning point in conscription, with the famed levée en masse, which coincided with dramatic changes in warfare and how states mobilized their polities for war. Less well known is how rarely conscripts were actually used in the wars that followed the French Revolution. Rather than being a turning point in the history of military recruitment, the levée en masse was just another moment in the ebb and flow of how states recruit military manpower in response to economics, threat, and political heritage.

A number of dimensions describe the extraordinary variety of compulsory recruitment systems. The two most important of these dimensions are whether conscription is institutionalized or opportunistic, and whether it is core or supplementary. The typology of compulsory recruitment systems that results describes a great deal of the varieties of conscription and, along with other dimensions, might give clues as to how states will recruit military manpower in the future.
Sudan: Soldiers and Civilians, 1958–2019
Authors: Woodward Peter
Published: October 2020

Sudan has had an unstable relationship between soldiers and civilians since shortly after it came to independence in 1956. This has resulted in three military coups, in 1958, 1969, and 1989, all of which gave rise to successful, peaceful civilian resistance seeking democratic government in 1964, 1985, and 2018. In the south of the country, two lengthy civil wars started under periods of military rule and resulted in separation and the creation of South Sudan in 2011, in which the very definition of “soldiers” and “civilians” is central to continuing conflicts.