1,892 research outputs found
Effects of Electromagnetic Field on the Dynamical Instability of Cylindrical Collapse
The objective of this paper is to discuss the dynamical instability in the
context of Newtonian and post Newtonian regimes. For this purpose, we consider
non-viscous heat conducting charged isotropic fluid as a collapsing matter with
cylindrical symmetry. Darmois junction conditions are formulated. The
perturbation scheme is applied to investigate the influence of dissipation and
electromagnetic field on the dynamical instability. We conclude that the
adiabatic index has smaller value for such a fluid in cylindrically
symmetric than isotropic sphere
WHAT FACTORS MOST? IMPACT OF PROGRAMME QUALITY DIMENSIONS ON SECONDARY SCHOOL STUDENTS’ SATISFACTION WITH BIOSYSTEMS TECHNOLOGY PROGRAMME IN SRI LANKA
In general, education quality can be conceptually determined by the evaluation of students’ satisfaction. In fact, satisfying the students in programme of studies is a key element which directly effect on future students’ intake to a programme or course. The purpose of present study was to determine the impact of programme quality on students' satisfaction amongst the Sri Lankan senior secondary schools students and to analyze which dimensions of programme quality contribute the most in achieving students' satisfaction. This study used quantitative method and administered a questionnaire to 410 Biosystems Technology students from senior secondary schools in the central province of Sri Lanka. The findings revealed that programme quality is an important antecedent and determinant of the students' satisfaction with their programme of study. Interestingly, the findings indicated that subject availability for electives is the critical factor that contributes the most on students' satisfaction followed by subject content in major, classroom environment and class size and also school facilities and learning resources. Thus, the findings of the present study have provided significant contribution to the body of the knowledge in programme quality and students' satisfaction and also relevant authorities in general education such as policymakers, curriculum developers, and other relevant personnel to make necessary amendments to be improve the quality of existing programme that ensures the students' satisfaction. Article visualizations
Raman and Computational Study on the Adsorption of Xanthine on Silver Nanocolloids
Xanthine is a nucleobase, deriving from adenine and guanine by deamination and oxidation processes, which may deposit in the human body causing diseases, similar to uric acid. Here, we have investigated the adsorption of xanthine on silver colloidal nanoparticles by means of surface-enhanced Raman scattering (SERS) with an exciting radiation in the near-infrared spectral region, where interference due to fluorescence does not occur, along with density functional theory calculations of molecule/metal model systems. By adopting a combined experimental and computational approach, we have identified the "marker" SERS bands of xanthine and the tautomer that preferentially binds the silver particles, as well as the molecular group involved in the interaction with metal. This investigation allows using the FT-SERS spectroscopy for biosensory and diagnostic purposes in body fluids, detecting abnormal levels of xanthine, and preventing metabolic diseases
STUDENTS’ SATISFACTION TOWARDS BIOSYSTEMS TECHNOLOGY; DOES PROGRAMME QUALITY MATTERS? (EVIDENCE FROM SRI LANKAN PERSPECTIVES)
In the competitive education setting, with declining students’ enrolment into the programme of study, the policy makers, curriculum developers and other relevant personnel should pay much attention to address the issue of attracting secondary students into job market demanded programmes. The purpose of the present study was to examine the relationship between perceived programme quality and the students’ satisfaction in selected government schools in Sri Lanka. The present study applied quantitative design using 410 senior secondary students who studied Biosystems Technology. The conceptual framework has been formulated based on the comprehensive review of the past studies. Multiple regression analysis was used to test the relationships among the dimensions of programme quality and students’ satisfaction as hypothesized. The finding indicated that the dimensions of programme quality have been correlated significantly with secondary students’ satisfaction whilst there was a positive and significant relationship amongst the four dimensions of programme quality and students’ satisfaction towards Biosystems Technology programme. Thus, the finding of current study has provided significant contribution to the existing body of knowledge in terms of offering statistically established conceptual framework and a validated measuring scale in satisfaction to the general education system. Furthermore, the implications were provided for the policy makers and relevant personnel to make remedial measures in order to quality improvement of Biosystems Technology programme. Article visualizations
Comparison of IPM packages on flower thrips and pod borers management of mungbean with recommended practice
Effectiveness of integrated management approaches using blue sticky trap, pheromone trap, bio and synthetic insecticides were evaluated against major insects, like flower thrips and pod borers of mungbean at Regional Agricultural Research Station, Rahmatpur, Barishal and Pulses Research Centre, Ishurdi,Pabna, Bangladesh, respectively, during
two consecutive years of 2018 and 2019. All of the management packages significantly reduced flower infestation, thrips population and pod borer infestation in mungbean. The highest percentage of reduction of flower infestation, thrips population and pod borer infestation was found in IPM package-3: installing blue sticky trap + two spraying of chlorfenapyr (Intrepid 10 EC) @ 1 ml/l + third spraying with (chlorantraniliprole + thiamethoxam), i.e. Virtako 40 WG) @ 0.15 g/l, followed by IPM package-1, IPM package-2 and recommended practice (spraying imidacloprid, i.e. Imitaf 20 SL @ 0.5 ml/l). The highest yield was also recorded from IPM package-3, which was statistically similar to IPM package-1, followed by IPM package-2 and recommended practice. Although the IPM
package-3 provided the highest yield and return, followed by IPM package-1, but
recommended practice (farmer’s practice) gave the highest benefit because of higher
cost of IPM components brought down the profit margin of IPM packages. The components of IPM package-1, i.e. biopesticides, are ecologically safer than that of IPM package-3 (synthetic chemical insecticides). So, considering environment friendliness, the IPM package-1: installation of blue sticky trap and pheromone trap + two spraying of
azadiractin (Biomeem plus 1EC) @ 1 ml/l + third spraying with spinosad (Success
2.5 EC) @ 1.2 ml/l would be the best package for controlling flower thrips and pod borers of mungbean with higher yield in the insects prone areas, without harming the ecosystem
Precursors, black holes, and a locality bound
We revisit the problem of precursors in the AdS/CFT correspondence.
Identification of the precursors is expected to improve our understanding of
the tension between holography and bulk locality and of the resolution of the
black hole information paradox. Previous arguments that the precursors are
large, undecorated Wilson loops are found to be flawed. We argue that the role
of precursors should become evident when one saturates a certain locality
bound. The spacetime uncertainty principle is a direct consequence of this
bound.Comment: 26 pages, 8 figs; reference added, minor clarification in sec. 2;
incorrect draft mistakenly used in version
Bionic 3D printed corals.
Corals have evolved as optimized photon augmentation systems, leading to space-efficient microalgal growth and outstanding photosynthetic quantum efficiencies. Light attenuation due to algal self-shading is a key limiting factor for the upscaling of microalgal cultivation. Coral-inspired light management systems could overcome this limitation and facilitate scalable bioenergy and bioproduct generation. Here, we develop 3D printed bionic corals capable of growing microalgae with high spatial cell densities of up to 109 cells mL-1. The hybrid photosynthetic biomaterials are produced with a 3D bioprinting platform which mimics morphological features of living coral tissue and the underlying skeleton with micron resolution, including their optical and mechanical properties. The programmable synthetic microenvironment thus allows for replicating both structural and functional traits of the coral-algal symbiosis. Our work defines a class of bionic materials that is capable of interacting with living organisms and can be exploited for applied coral reef research and photobioreactor design
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Guidelines for consideration of bats in lighting projects.
Eighty percent of the world’s population are currently exposed to light-polluted skies, and the Milky Way is no longer visible to more than a third of humanity. The pace the light pollution is increasing is faster than global population growth and economic development. While environmental conditions at night are being dramatically and rapidly altered, circadian rhythms, behaviour and ecology of plants and animals are imminently influenced. In the same time, effects of artificial lighting, various illumination schemes and spectra on biodiversity, including bats, are currently insufficiently understood, whereas only a vague notion of required mitigation and compensation activities exists among decision-makers and other parties involved in lighting projects. Although the bats are almost exclusively nocturnal and extremely sensitive to multiple effects of light pollution, its negative impact on bats alongside essential measures needed to preserve unfragmented nightscapes for these animals are often disregarded during impact assessments, planning and operation.
In this volume, we tried to compile available evidence related to the effect of artificial light at night on the European bats. Based on the current state of knowledge, solutions are proposed concerning possible ways to avoid, mitigate and compensate the adverse effects which lighting projects may have on bats and their functional habitats. We also outlined research priorities for future studies, required for in-depth understanding of the problem and assessing efficiency of proposed mitigative measures
Kurt Symanzik - a stable fixed point beyond triviality
In 1970 Kurt Symanzik proposed a "precarious" phi**4-theory with a negative
quartic coupling constant as a valid candidate for an asymptotically free
theory of strong interactions. Symanzik's deep insight in the non-trivial
properties of this theory has been overruled since then by the Hermitian
intuition of generations of scientists, who considered or consider this
actually non-Hermitian highly important theory to be unstable. This short -
certainly controversial - communication tries to shed some light on the
historical and formalistic context of Symanzik's theory in order to sharpen our
(quantum) intuition about non-perturbative theoretical physics between
(non)triviality and asymptotic freedom.Comment: 6 pages, no figures, new style files, revised for typos, improved
discussion, new references adde
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