Energy-Momentum Problem of Bell-Szekeres Metric in General Relativity and Teleparallel Gravity

This paper is devoted to the investigation of the energy-momentum problem in two theories, i.e., General Relativity and teleparallel gravity. We use Einstein, Landau-Lifshitz, Bergmann-Thomson and M\"{o}ller's prescriptions to evaluate energy-momentum distribution of Bell-Szekeres metric in both the theories. It is shown that these prescriptions give the same energy-momentum density components in both General Relativity and teleparallel theory. M\"{o}ller's prescription yields constant energy in both the theories.Comment: 21 pages, accepted for publication in Braz. J. Phy

Autonomous monitoring framework for resource-constrained environments

Acknowledgments The research described here is supported by the award made by the RCUK Digital Economy programme to the dot.rural Digital Economy Hub, reference: EP/G066051/1. URL: http://www.dotrural.ac.uk/RemoteStream/Peer reviewedPublisher PD

PENGARUH LAMA PERENDAMAN DALAM LARUTAN KALSIUM HIDROKSIDA (CA(OH)2) PADA PEMBUATAN TEPUNG BIJI ALPUKAT

Pengaruh Lama Perendaman Dalam Larutan Kalsium Hidroksida (Ca(OH)2)Pada Pembuatan Tepung Biji AlpukatThe influence of Soaking Time in Calcium Hydroxide (Ca(OH)2) solutioninAvocado Seed Flour ProcessingMuhammad Nazir Shadiq1,Raida Agustina1, Rita Khathir1*1Program Studi Teknik Pertanian, Fakultas Pertanian, Universitas Syiah KualaAbstrak. Penelitian ini bertujuan untuk mengetahui pengaruh variasi lama perendaman biji alpukatdalam larutan kalsium hidroksida dengan konsentrasi 3000 ppm terhadap mutu tepung biji alpukat.Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) non faktorial dengan variasi lamaperendaman 0, 20, 40 dan 60 menit. Parameter penelitian meliputi rendemen, kadar air, kadar abu,derajat keasaman (pH), kadar pati serta uji hedonik terhadap warna dan aroma. Uji hedonikdilakukan terhadap 30 orang panelis.Hasil dari penelitian ini menunjukkan bahwa variasi lamaperendaman dalam larutan kalsium hidroksida 3000 ppm memberikan pengaruh nyata terhadapderajat keasaman (pH), tetapi tidak memberikan pengaruh nyata terhadap rendemen, kadar air,kadar abu, kadar pati, dan uji hedonik terhadap warna dan aroma. Berdasarkan hasil uji lanjut BedaNyata Jujur (BNJ), dapat disimpulkan bahwa perlakuan terbaik didapatkan pada perlakuan lamaperendaman selama 20 menit dimana diperoleh nilai pH sebesar 6,94. Pada perlakuan tersebutdiperoleh rendemen sebesar 21,27%, kadar air 7,31%, kadar abu 1,25%, kadar pati 80,86%, skorkesukaan terhadap warna 3 (netral) dan skor kesukaan terhadap aroma 3 (netral).Kata kunci : biji alpukat, lama perendaman, kalsium hidroksida,tepung biji alpukatAbstract. The study aimed to determine the effect of soaking time calcium hydroxide solution withconcentration of 3000 ppm to the quality of avocado seed flour.This study was conducted by usingcomplete random design (CRD) non factorialunder the variation of soaking time 0, 20, 40 and 60minutes.The parameters observed wereyield, moisture, ash, acidity, and starch content, and thehedonic perception on colour and favour. The hedonic test was examinated to 30 consumers.Results showed that the treatment had significant impact on acidity but did not give significantimpact on other parameters. Based on the honestly significance difference (HSD) test, the besttreatment was indicated at 20 minutes soaking time in the solution with the acidity of 6.94. At thecondition it was determined that the yield of flour was 21.27%, the moisture content was about7.31%, the ash content was 1.25%, the starch content was approximately 80.86%, and theconsumers perceptions on colour and favour were 3 (neutral).Keywords : avocado seed, soaking time, calcium hydroxide, avocado seed flour

Experimental Studies on Pulmonary Vascular Response to Alveolar Hypoxia during Almitrine Infusion in Anesthetized Dogs

Almitrine bismesylate, a peripheral chemoreceptor stimulant has been shown to increase arterial oxygen tension in patients with chronic airflow obstruction. This effect is thought to be partly attributable to the enhancement of hypoxic pulmonary vasoconstriction (HPV). However, regarding this point the results of various clinical and animal studies on almitrine are inconclusive. The aim of this study was to investigate the effect of almitrine on HPV in anesthetized, open chested dogs. HPV was expressed in terms of flow diversion associated with hypoxic challenge to the left lower lobe (LLL) where LLL and the rest of the lung were separately ventilated. Results showed that the HPV was enhanced by relatively lower doses of almitrine infusion while attenuated by higher doses. Stimulus-response curves (relationship between end-tidal oxygen pressure and LLL blood flow) showed shift to the right, indicating that almitrine induced the pulmonary vasoconstriction dose-dependently at progressively higher end-tidal oxygen tensions during LLL hypoxic challenges. This suggested that almitrine, also enhanced the response of pulmonary vessels to hypoxia. These changes were not found during almitrine vehicle infusion. Plasma level of 6-keto-PGF1α, the stable metabolite of PGI2 did not show any significant changes after infusion of almitrine. Besides this, following denervation of peripheral chemoreceptors, some dogs showed the same effects as observed in those without chemoreceptor denervation i,e HPV was enhanced by low doses of almitrine and attenuated by higher doses where stimulus-response curves also shifted towards the right. Doxapram, another chemoreceptor stimulant drug did not enhance or attenuate HPV. The effect of almitrine was not influenced by blocking the Ca++ entry through the voltage dependent channel. It was therefore concluded that vasoconstriction induced by almitrine may be attributed to a direct effect on pulmonary vessels rather than being mediated via the peripheral chemoreceptors.This study was performed in the Second Department of Internal Medicine, Hiroshima University School of Medicine, under a scholarship granted by the Ministry of Education, Science and Culture (Monbusho), The Government of Japan

High fidelity all-optical control of quantum dot spins: detailed study of the adiabatic approach

Confined electron spins are preferred candidates for embodying quantum information in the solid state. A popular idea is the use of optical excitation to achieve the ``best of both worlds'', i.e. marrying the long spin decoherence times with rapid gating. Here we study an all-optical adiabatic approach to generating single qubit phase gates. We find that such a gate can be extremely robust against the combined effect of all principal sources of decoherence, with an achievable fidelity of 0.999 even at finite temperature. Crucially this performance can be obtained with only a small time cost: the adiabatic gate duration is within about an order of magnitude of a simple dynamic implementation. An experimental verification of these predictions is immediately feasible with only modest resources

Systemic Approach to Teaching and Learning Chemistry (SATLC) as Integrated Approach towards Teaching Physical Chemistry

Enthusiasm is crucially needed in teaching and learning of chemistry at educational institutes. Issues and problems in achieving that end needs to be addressed on top priority. In this scenario the role of the instructor is of vital significance. A teacher can minimize the difficulties in concept building by providing better perspective related to the basics of the subject. This can be accomplished through novel efforts involving personal input. The recently emerged concept based teaching methodology, systemic approach to teaching and learning chemistry (SATLC), is a fascinating route to meet this noble endeavor. This new teaching method has been discovered to play a pivotal role, towards the efforts for promoting better understanding of chemical concepts. In addition to that, the results reported from the evaluation of SATL technique have been very promising as far as the improvements in students' academic achievements are concerned. In this presentation we discuss some examples that highlight the efficacy of SATLC based teaching method for providing clear understandings of some salient concepts in physical chemistry