1,256 research outputs found
Rank one preservers between spaces of boolean matrices
In this paper. we characterize (i) linear transformations from one space of Boolean matrices to another that send pairs of distinct rank one elements to pairs of distinct rank one elements and (ii) subjective mappings from one space of Boolean matrices to another that send rank one matrices to rank one matrices and preserve order relation in both directions. Both results are proved in a more general setting of tensor products of two Boolean vector spaces of arbitrary dimension
Enhanced Luminescence of InGaN / GaN Vertical Light Emitting Diodes with an InGaN Protection Layer
We have investigated the effectiveness of a thin n-In0.2Ga0.8N layer inserted in the bottom n-GaN layer
of InGaN/GaN blue light emitting diodes (LEDs) for the protection of multiple quantum wells during the
laser lift-off process for vertical LED fabrication. The photoluminescence properties of the InGaN/GaN
lateral LEDs are nearly identical irrespective of the existence of the n-In0.2Ga0.8N insertion layer in the
bottom n-GaN layer. However, such an insertion is found to effectively increase the photoluminescence
intensity of the multiple quantum well and the carrier lifetime of the vertical LEDs. These improvements
are attributed to the reduced defect generations in the vertical LEDs during the laser lift-off process due to
the presence of the protection layer.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3521
The Triple Bottom Line: Portable Applications and Best Practices for Sustainability in Academic Libraries
Triple Bottom Line Accounting (TBLA) refers to a method of measuring the economic, environmental, and community service impacts of an organization rather than the traditional practice of measuring just the financial bottom line. This chapter explores TBLA from a historical point-of-view; offers examples in higher education and discusses the implications for academic libraries. It concludes with ideas for the implementation of TBLA in libraries
Maternity of emergency queens in the Cape honey bee, Apis mellifera capensis
During reproductive swarming, some workers of the Cape honey bee, Apis mellifera
capensis, lay eggs in queen cells, many of which are reared to maturity. However, it is
unknown if workers are able to lay in queen cells immediately after queen loss during an
episode of emergency queen rearing. In this study we experimentally de-queened colonies and determined the maternity of larvae and pupae that were reared as queens. This allowed us to determine how soon after queen loss workers contribute to the production of new queens. We were further interested to see if workers would preferentially raise new queens from queen-laid brood if this was introduced later. We performed our manipulations in two different settings: an apiary setting where colonies were situated close together and a more natural situation in which the colonies were well separated. This allowed us to determine how the vicinity of other colonies affects the
presence of parasites. We found that workers do indeed contribute to queen cell production immediately after the loss of their queen, thus demonstrating that some
workers either have activated ovaries even when their colony has a queen or are able to
activate their ovaries extremely rapidly. Queen-laid brood introduced days after queen
loss was ignored, showing that workers do not prefer to raise new queens from queen
brood when given a choice. We also detected non-natal parasitism of queen cells in both
settings. We therefore conclude that some A. m. capensis genotypes specialize in
parasitizing queen cells.Centre of Excellence for Invasion Biolog
Game Theoretical Interactions of Moving Agents
Game theory has been one of the most successful quantitative concepts to
describe social interactions, their strategical aspects, and outcomes. Among
the payoff matrix quantifying the result of a social interaction, the
interaction conditions have been varied, such as the number of repeated
interactions, the number of interaction partners, the possibility to punish
defective behavior etc. While an extension to spatial interactions has been
considered early on such as in the "game of life", recent studies have focussed
on effects of the structure of social interaction networks.
However, the possibility of individuals to move and, thereby, evade areas
with a high level of defection, and to seek areas with a high level of
cooperation, has not been fully explored so far. This contribution presents a
model combining game theoretical interactions with success-driven motion in
space, and studies the consequences that this may have for the degree of
cooperation and the spatio-temporal dynamics in the population. It is
demonstrated that the combination of game theoretical interactions with motion
gives rise to many self-organized behavioral patterns on an aggregate level,
which can explain a variety of empirically observed social behaviors
Thermoluminescence (TL) dosimeter of dysprosium doped strontium borate glass for different glass modifiers (Na, Li, Ca) subjected from 1 to 9 Gy doses
Cognitive Ability and Cardiovascular Control in Intellectually and Developmentally Disabled People
Earlier, we examined positive effects of hyperoxic air on the cognitive ability of intellectually
and developmentally disabled people (IDDP). In this study, correlation between cognitive
performance in the visual matching task and heart rate (HR) was investigated under normal
air conditions. Eighteen men (mean age 28.7 ± 5.0 year) and 22 women (mean age 35.5 ± 6.9
year) with an assessed disability level of 2.3 ± 0.6 participated. The experiment consisted of
three phases, a total of 7 min, including the rest (3 min), control (2 min), and visual matching
task 2 min phases. The HR in visual matching task phase increased, compared to those in the
rest and control phases. The cognitive ability in the visual matching task correlated with the
HR values; the response time showed a negative correlation with HR, while the accuracy rate
showed a positive correlation. Thus, adaptive changes in cardiovascular regulation probably
related to cognitive efforts and emotional excitation should be considered a noticeable factor
influencing brain supply with oxygen in IDDP (similarly to healthy people). The result of this
study agrees with the earlier obtained indications that hyperoxic air can positively affect the
cognitive performance in IDDP.Раніше ми вивчали позитивні впливи повітря, збагаченого
киснем, на когнітивні здатності людей з недостатнім інтелектуальним розвитком (НІР). У нашій роботі ми досліджували кореляцію між показниками когнітивної активності в
тесті візуальної відповідності та частотою серцевих скорочень (ЧСС) у таких суб’єктів в умовах дихання нормальним
повітрям. У тестах брали участь 18 чоловіків (середній вік
28.7 ± 5.0 року) та 22 жінки (35.5 ± 6.9 року) з оцінкою рівня
інтелектуального розвитку 2.3 ± 0.6. Експеримент (загальна
тривалість 7 хв) складався з трьох фаз: стан розслаблення
(3 хв), контроль (2 хв) та тест візуальної відповідності
(2 хв). Величини ЧСС у межах цього тесту порівняно з величинами в умовах розслаблення й контролю зростали. Показники когнітивних здібностей корелювали з величинами
ЧСС; кореляція часу відповіді була негативною, а точності відповіді – позитивною. Отже, адаптивні зміни регуляції
серцево-судинної системи, мабуть, пов’язані з когнітивними
зусиллями та емоційним збудженням, є істотним фактором,
який впливає на постачання мозку киснем у людей із НІР
(як і у здорових людей). Результати нашої роботи узгоджуються з отриманими раніше свідоцтвами про те, що дихання
повітрям, збагаченим киснем, позитивно впливає на когнітивні можливості людей із НІР
Photocatalytic treatment technology for palm oil mill effluent (POME) – A review
This review provides insight into various techniques utilized for the treatments of palm oil mill effluents (POME). Generally, POME treatment is achieved in two ways, these are (1) pre-treatment stages, involving majorly the reduction of oil and grease and suspended matter and (2) an advanced treatment stage, in which wastewater contaminants (e.g. BOD5, COD) are reduced to standard discharge limits. Different methods utilized in the treatment of POME such as coagulation-flocculation, anaerobic, aerobic and membrane technology are explained fully and recent trends in their advancement and improvement are outlined. Though, various pilot or industrial scale treatment plants have been reported in scientific literature for POME treatments methods such as anaerobic, aerobic and membrane technology, the literature is still scarce for application of photocatalytic degradation technology to POME treatment as the technology is still in development stage and has not been fully utilized on an industrial scale in palm oil mill industries. This is mainly as a result of inadequate investigation involving POME degradation. The review presented here is focused on photocatalytic degradation technology and reflects published outcomes with the aim of offering the technique as an attractive and sustainable process units. Also the potential of the process to replace some of the well-known separation and degradation technologies has been highlighted at advanced treatment stage for POME
The state-of-the-art development of photocatalysts for degrading of persistent herbicides in aqueous environment
Herbicides are one of the most recurring pollutants in the aquatic system due to their widespread usage in the agriculture sector for weed control. Semiconductor-based photocatalysts have gained recognition due to their ability to degrade and mineralize pollutants into harmless by-products completely. Lately, many studies have been done to design photocatalysts with efficient separation of photogenerated charge carriers and enhanced light absorption. Photocatalyst engineering through doping with metal and non-metal elements and the formation of heterojunction are proven effective for minimizing the recombination of electron-hole pairs and enlarging the absorption in the visible light region. This review focuses on discussing and evaluating the recent progress in the types of photocatalysts and their performance in the remediation of herbicides in wastewater. The development of innovative hybrid technologies is also highlighted. The limitations and challenges of photocatalysis technology in the present literature have been identified, and future studies are recommended
Scaling limit of virtual states of triatomic systems
For a system with three identical atoms, the dependence of the wave
virtual state energy on the weakly bound dimer and trimer binding energies is
calculated in a form of a universal scaling function. The scaling function is
obtained from a renormalizable three-body model with a pairwise Dirac-delta
interaction. It was also discussed the threshold condition for the appearance
of the trimer virtual state.Comment: 9 pages, 3 figure
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