Ab initio study on the magneto-structural properties of MnAs

The magnetic and structural properties of MnAs are studied with ab initio methods, and by mapping total energies onto a Heisenberg model. The stability of the different phases is found to depend mainly on the volume and on the amount of magnetic order, confirming previous experimental findings and phenomenological models. It is generally found that for large lattice constants the ferromagnetic state is favored, whereas for small lattice constants different antiferromagnetic states can be stabilized. In the ferromagnetic state the structure with minimal energy is always hexagonal, whereas it becomes orthorhombically distorted if there is an antiferromagnetic component in the hexagonal plane. For the paramagnetic state the stable cell is found to be orthorhombic up to a critical lattice constant of about 3.7 Angstrom, above which it remains hexagonal. This leads to the second order structural phase transition between paramagnetic states at about 400 K, where the lattice parameter increases above this critical value with rising temperature due to the thermal expansion. For the paramagnetic state an analytic approximation for the magnitude of the orthorhombic distortion as a function of the lattice constant is given. Within the mean field approximation the dependence of the Curie temperature on the volume and on the orthorhombic distortion is calculated. For orthorhombically distorted cells the Curie temperature is much smaller than for hexagonal cells. This is mainly due to the fact that some of the exchange coupling constants in the hexagonal plane become negative for distorted cells. With these results a description of the susceptibility as function of temperature is given

STRUCTURE POPULATION OF PINE WOOLLY ADELGIDS (Hemiptera : Adelgidae) IN PERUM PERHUTANI UNIT III, WEST JAVA AND BANTEN, KPH SUMEDANG

Pinus boerneri as Pine Woolly Adelgids, emergence rapidly around Pinus Plantation in Indonesia has been reported since last decade. This pest causing dieback, defoliated branches, and even death to the tree. The aim of this study to investigate the population structure of pine wooly adelgid attack in Pine forest (Pinus merkusii) in Perum Perhutani Unit III, West Java and Banten, KPH Sumedang. This research important as consideration about the distribution of pine wooly adelgid stages in presumtive level of consequential damage. There were three part of Pine twigs (crown, middle, and lower) from 18 trees that positively attacked being collected. Later on, twigs diameter and number of each pine woolly adelgids stages (egg, nymph and imago) from every twigs part been observed. Result shows that imago as the dominant stage that infested in Pine forest in Perum Perhutani Unit III, KPH Sumedang. Damage level that effect by P. boerneri devided into two categories light infested and heavy infested.Key words : Hemiptera, Pine Woolly Adelgid, P. boerneri, Pest, P. merkusi

Molasses Injection to Improve Growth and Vitality of Kesambi (Schleicera Oleosa Merr) as Lac Insect Host Plant

Lac is a non-timber forest product derived from the secretion of Laccifer lacca insects that are cultivated in kesambi tree (Schleicera oleosa Merr). Low lac production in Indonesia due to poor conditions of host plant indicated by poor growth symptoms, yellowing, and falling leaves. The aim of this research was to study the effect of molasses injection on the growth and vitality of kesambi tree. Molasses were injected into the plant using passive liquid injection methods. Pre-research activities were carried out by the tree trunk injection in 0.5, 1.5, and 2 meters above the ground using gentian violet to determine the best stem injection position, while the main research activity was performed by injection of the kesambi tree trunk using molasses in concentrations of 5, 10, 15% and water as control. The parameters measured at the pre-study was translocation length of gentian violet whereas at the main research were the volume uptake, the increase of branch diameter growth, total sugar content and chlorophyll content. Pre-research results showed that 1.5 meters above the ground is the best injection position. The main research results indicated that the highest volume uptake was water followed by others treatments. Molasses injection at concentration of 10% gives better effect on the increase of branch diameter growth (4.3 mm), obtained sugar content in 18.46%. The vitality of kesambi tree also increased by the molasses injection at concentration of 10%. It was shown by thein creased of chlorophyll a (1.117 mg/g), b (0.416), carotene (0.365), and Anthocyanin (0.094 mg/100g)

Perbandingan Komunitas Kupu-kupu pada Berbagai Tipe, Karakteristik, dan Gangguan Lingkungan Hutan Kota

Butterfly has many ecological roles and it can be found in a wide range of habitats in urban areas. Urban forest as one of the butterfly habitat in urban areas has high conservation value, in contrast, environmental disturbances have been indicated causes various changes in urban forest environmental condition and affect communities that exist within it, including butterfly. This research aims to compare and analyze butterfly communities in various types, characteristics, and environmental disturbances of urban forest. The surveys were carried out at four types of urban forest (residential, industrial, recreational,and highway types) in East Jakarta Municipality on three different periods (dry, dry-wet transitional, and wet seasons) from October 2014 to Januari 2015 by using Pollard Transect method. Study showed that butterfly diversity was decreasing within increasing degree of environmental disturbance. Transitional period and urban forest in residential area had the highest species richness and diversity, moreover, recreational and residential types of urban forest had the highest community similarity in all seasons

MODIFIED SERIES RESISTANCE MODEL - DETERMINATION OF MEAN CONCENTRATION BY INTEGRAL TRANSFORMATION

There are several mathematical models that describe permeate flow in membrane separation processes. Among these, the series resistance model plays a prominent role. It takes into account membrane strength, concentration polarization, polarized layer and fouling to describe the permeate flow over time. In this work, an analysis of the modified series resistance model was performed, in which the resistance by polarization of the concentration is defined as being directly proportional to the transmembrane pressure. The proportionality constant is given by the product of a specific coefficient of resistance – which is determined by means of experimental data – the thickness of the boundary layer of concentration and the mean concentration. Due to the inability to obtain experimentally the value of the average concentration within the boundary layer of concentration, its simulation is carried out from the conservation equation of the chemical species. Thus, the objective of the present work was to solve the equation of the conservation of chemical species using GITT (Generalized Integral Transform Technique) and apply the modified series resistance model to describe the permeate flow of a solution of dextran through a permeable tube under laminar flow. GITT provided satisfactory results for the mean concentration, verified by comparison with the permeate flow obtained by the series resistance model with experimental results reported in the literature

Serangan Arthroschista Hilaralis Walk. (Lepidoptera: Pyralidae) pada Tegakan Jabon (Neolamarckia Cadamba [Roxb.] Bosser) di Sumatera Selatan

Serangan hama merupakan masalah utama yang dihadapi dalam budi daya jabon (Neolamarckia cadamba [Roxb.] Bosser) di Indonesia khususnya di Sumatera Selatan. Arthroschista hilaralis Walk. (Lepidoptera: Pyralidae) merupakan salah satu hama penting yang menyerang tanaman jabon. Informasi mengenai tingkat serangan A. hilaralis pada tegakan jabon diperlukan sebagai bahan pertimbangan pengelolaan A. hilaralis. Tujuan penelitian ini adalah mengkaji insidensi dan intensitas serangan A. hilaralis yang menyerang tegakan jabon umur 2 dan 4 tahun selama 2 musim pengamatan, serta mengkaji pengaruh faktor cuaca (suhu dan kelembaban udara) terhadap serangan A. hilaralis. Penelitian ini dilaksanakan pada 6 lokasi yang terletak pada beberapa daerah di Sumatera Selatan. Pada setiap lokasi penelitian ditentukan 3 plot masing-masing seluas 0,03 ha dan berisi 20 tanaman jabon. Pengamatan insidensi dan intensitas serangan A. hilaralis dilakukan sebulan sekali selama 16 bulan yang mewakili 2 kategori waktu pengamatan, yaitu musim hujan dan musim kemarau. Hasil penelitian menunjukkan bahwa serangan A. hilaralis paling tinggi terjadi pada tegakan jabon umur 2 tahun dan pada musim hujan dengan insidensi dan intensitas serangan masing-masing sebesar 74,45% dan 55,21%. Faktor cuaca (suhu dan kelembaban udara) berpengaruh terhadap tingkat serangan A. hilaralis. Suhu udara berkorelasi negatif terhadap insidensi (r = -0,629; p = 0,009) dan intensitas serangan A. hilaralis (r = -0,546; p = 0,029), sedangkan kelembaban udara berkorelasi positif terhadap insidensi (r = 0,900; p < 0,0001) dan intensitas serangan A. hilaralis (r = 0,768; p = 0,0005)

5G 3GPP-like Channel Models for Outdoor Urban Microcellular and Macrocellular Environments

For the development of new 5G systems to operate in bands up to 100 GHz, there is a need for accurate radio propagation models at these bands that currently are not addressed by existing channel models developed for bands below 6 GHz. This document presents a preliminary overview of 5G channel models for bands up to 100 GHz. These have been derived based on extensive measurement and ray tracing results across a multitude of frequencies from 6 GHz to 100 GHz, and this document describes an initial 3D channel model which includes: 1) typical deployment scenarios for urban microcells (UMi) and urban macrocells (UMa), and 2) a baseline model for incorporating path loss, shadow fading, line of sight probability, penetration and blockage models for the typical scenarios. Various processing methodologies such as clustering and antenna decoupling algorithms are also presented.Comment: To be published in 2016 IEEE 83rd Vehicular Technology Conference Spring (VTC 2016-Spring), Nanjing, China, May 201

Carnosine scavenging of glucolipotoxic free radicals enhances insulin secretion and glucose uptake

The worldwide prevalence of diabetes has risen to 8.5% among adults, which represents a staggering rise in prevalence from 4.7% in 1980. Whilst some treatments work by increasing insulin secretion, over time their effectiveness decreases. We aim to increase insulin secretion by developing strategies that work through mechanisms independent of current treatment options. Isolated CD1 mouse islets, INS-1 pancreatic β-cells, or C2C12 mouse myotubes were incubated in standard tissue culture media, or media supplemented with 28 mM glucose, 200 μM palmitic acid, and 200 μM oleic acid as a cellular model of diabetic glucolipotoxicity. Intracellular reactive species content was assayed using 2′,7′-dichlorofluorescein diacetate dye, inducible nitric oxide synthase levels determined by Western blot, 3-nitrotyrosine and 4-hydrpxnonenal both assayed by ELISA, insulin secretion quantified using ELISA or radioimmunoassay, and glucose uptake determined through 2-deoxy glucose 6 phosphate luminescence. Our data indicate that carnosine, a histidine containing dipeptide available through the diet, is an effective scavenger of each of the aforementioned reactive species. This results in doubling of insulin secretion from isolated mouse islets or INS-1 β-cells. Crucially, carnosine also reverses glucolipotoxic inhibition of insulin secretion and enhances glucose uptake into skeletal muscle cells. Thus, carnosine, or non-hydrolysable carnosine analogs, may represent a new class of therapeutic agent to fight type 2 diabetes

Successful recovery of infective endocarditis-induced rapidly progressive glomerulonephritis by steroid therapy combined with antibiotics: a case report

BACKGROUND: The mortality rate among patients with infective endocarditis, especially associated with the presence of complications or coexisting conditions such as renal failure and the use of combined medical and surgical therapy remains still high. Prolonged parenteral administration of a bactericidal antimicrobial agent or combination of agents is usually recommended, however, the optimal therapy for infective endocarditis associated with renal injury is not adequately defined. CASE PRESENTATION: Patient was a 24-years old man who presented to our hospital with fever, fatigue, and rapidly progressive glomerulonephritis. He had a history of ventricular septum defect (VSD). A renal biopsy specimen revealed crescentic glomerulonephritis and echocardiogram revealed VSD with vegetation on the tricuspid valve. Specimens of blood demonstrated Propionibacterium Acnes. The intensive antibiotic therapy with penicillin G was started without clinical improvement of renal function or resolution of fever over the next 7 days. After the short-term treatment of low dose of corticosteroid combined with continuous antibiotics, high fever and renal insufficiency were dramatically improved. CONCLUSION: Although renal function in our case worsened despite therapy with antibiotics, a short-term and low dose of corticosteroid therapy with antibiotics was able to recover renal function and the patient finally underwent tricuspid valve-plasty and VSD closure. We suggest that the patients with rapidly progressive glomerulonephritis associated with infective endocarditis might be treated with a short-term and low dose of corticosteroid successfully