Dipole-Induced Electromagnetic Transparency

We determine the optical response of a thin and dense layer of interacting quantum emitters. We show that in such a dense system, the Lorentz redshift and the associated interaction broadening can be used to control the transmission and reflection spectra. In the presence of overlapping resonances, a Dipole-Induced Electromagnetic Transparency (DIET) regime, similar to Electromagnetically Induced Transparency (EIT), may be achieved. DIET relies on destructive interference between the electromagnetic waves emitted by quantum emitters. Carefully tuning material parameters allows to achieve narrow transmission windows in otherwise completely opaque media. We analyze in details this coherent and collective effect using a generalized Lorentz model and show how it can be controlled. Several potential applications of the phenomenon, such as slow light, are proposed

Theory of Dipole Induced Electromagnetic Transparency

A detailed theory describing linear optics of vapors comprised of interacting multi-level quantum emitters is proposed. It is shown both by direct integration of Maxwell-Bloch equations and using a simple analytical model that at large densities narrow transparency windows appear in otherwise completely opaque spectra. The existence of such windows is attributed to overlapping resonances. This effect, first introduced for three-level systems in [R. Puthumpally-Joseph, M. Sukharev, O. Atabek and E. Charron, Phys. Rev. Lett. 113, 163603 (2014)], is due to strongly enhanced dipole-dipole interactions at high emitters' densities. The presented theory extends this effect to the case of multilevel systems. The theory is applied to the D1 transitions of interacting Rb-85 atoms. It is shown that at high atomic densities, Rb-85 atoms can behave as three-level emitters exhibiting all the properties of dipole induced electromagnetic transparency. Applications including slow light and laser pulse shaping are also proposed

Need and Opportunities for a ‘Plan B’ in Rail Track Inspection Schedules

AbstractTrack inspection is purposely performed to recover tracks from defects and damage and eliminate potential safety hazards. It is scheduled through an exhaustive process that usually integrates many disciplines such as optimization, statistics, risk management, etc. Spending so much of a monetary and an emotional investment in an original schedule (referred to as master schedule hereafter) that the scheduler wants to deliver might be a good excuse not to develop a solid ‘Plan B’. Plan B here refers to scheduler responses or a contingency plan when the master schedule does not go as expected. It is found that there is often low to moderate probability of a crisis occurring when a schedule is executed in a real environment. Nevertheless, its impact can leave transportation services to the mercy of the disruption as shown by the Christmas 2014 incident where a huge volume of passengers using King's Cross and Paddington services experienced both inconvenience and discomfort due to engineering delays and train disruption. Thus, this paper aims to discuss the potential of considering ‘Plan B’ or contingency plan if incidents arise that were not expected during track inspection schedule execution. Benefits, general guidelines and relevant strategies for creating a contingency plan are also discussed. We highlight the rationale to support the claim that an original schedule of track inspection jobs should be adapted to respond to a new context e.g. inspection vehicle machine breakdown, new inspection requests, man-made hazards, terrorist attack, extreme weather, climate change, etc. It is however proposed to develop an appropriate set of performance measure that is used to guide rescheduling in track inspection due to financial, equipment inventory, manpower, safety regulations, time and spatial constraints

Structures of Two Melanoma-Associated Antigens Suggest Allosteric Regulation of Effector Binding

The MAGE (melanoma associated antigen) protein family are tumour-associated proteins normally present only in reproductive tissues such as germ cells of the testis. The human genome encodes over 60 MAGE genes of which one class (containing MAGE-A3 and MAGE-A4) are exclusively expressed in tumours, making them an attractive target for the development of targeted and immunotherapeutic cancer treatments. Some MAGE proteins are thought to play an active role in driving cancer, modulating the activity of E3 ubiquitin ligases on targets related to apoptosis. Here we determined the crystal structures of MAGE- A3 and MAGE-A4. Both proteins crystallized with a terminal peptide bound in a deep cleft between two tandem-arranged winged helix domains. MAGE-A3 (but not MAGE-A4), is pre- dominantly dimeric in solution. Comparison of MAGE-A3 and MAGE-A3 with a structure of an effector-bound MAGE-G1 suggests that a major conformational rearrangement is required for binding, and that this conformational plasticity may be targeted by allosteric binders

Vigorous Premalignancy-specific Effector T Cell Response in the Bone Marrow of Patients with Monoclonal Gammopathy

Most approaches targeting the immune system against tumors have focused on patients with established tumors. However, whether the immune system can recognize preneoplastic stages of human cancer is not known. Here we show that patients with preneoplastic gammopathy mount a vigorous T cell response to autologous premalignant cells. This preneoplasia-specific CD4+ and CD8+ T cell response is detected in freshly isolated T cells from the BM. T cells from myeloma marrow lack this tumor-specific rapid effector function. These data provide direct evidence for tumor specific immune recognition in human preneoplasia and suggest a possible role for the immune system in influencing the early growth of transformed cells, long before the development of clinical cancer

A Visual Simulation Support Environment Based on the DOMINO Conceptual Framework

The purpose of this paper is to present a Visual Simulation Support Environment (VSSE) based on the multifaceD coOnceptual fraMework for vIsual simulatioN mOdeling (DOMINO). The ever-increasing complexity of visual simulation model development is undeniable. There is a need for automated support throughout the entire visual simulation model development life cycle. This support is furnished by the VSSE which is composed of integrated software tools providing computer-aided assistance in the development and execution of a visual simulation model. The VSSE has been jointly developed with the DOMINO. Its architecture consists of three layers: hardware and operating system, kernel VSSE, minimal VSSE, and VSSEs. This paper focuses on the minimal VSSE toolset. Evaluation of the VSSE shows that it adequately satisfies all of its 13 design objectives

DOMINO: A Multifaceted Conceptual Framework for Visual Simulation Modeling

The purpose of this paper is to present a new conceptual framework for visual simulation modeling, the multifaceD coOnceptual fraMework for vIsual simulatioN mOdeling (DOMINO). The DOMINO provides both design and implementation guidance to furnish a broad range of support during the model development life cycle; enables the modeler to work under the object-oriented paradigm; guides the modeler in graphically structuring a visual simulation model at multiple levels of abstraction; enables the extraction of sufficient information from the modeler so that the model execution can be visualized; embodies a WYSIWYR (What You See Is What You Represent) philosophy and enables the modeler to represent a system as it is naturally perceived; among many other features

Yahudilik

oai:oai.mutefekkir.aksaray.edu.tr:article/

Physicochemical properties of imported and locally produced honey did not translate into its microbial quality and antibacterial activity

Honey is often considered a good substitute for sugar. However, concerns about the poor quality of locally produced honey have necessitated the importation of honey to meet the domestic demand in spite of Ghana’s good climatic conditions suitable for honey production. Due to the increasing level of demand for honey both locally and internationally, we highlighted here the need for an assessment of the physicochemical, microbiological quality, and antibiotics resistance of microbes isolated from the imported and locally produced honey vis-à-vis international standards. Thirty honey samples which comprise 7 imported and 23 locally produced were randomly sampled from retail outlets consisting of supermarkets, marts, shops, and open markets as well as from production sites within the northern region for physicochemical analysis, microbial analysis, and antibiogram. Results of the physicochemical quality analysis showed that sampled honey (both imported and locally produced) was within acceptable set standards. However, microbial quality was poor as a high incidence of bacterial contamination and resistance was recorded in the study. The High incidence of bacterial contamination and antibiotic resistance recorded in this study gives an indication that all is not well in the honey industry and therefore the need for appropriate measures to avert possible health issues associated with the consumption of honey found within the region

Uloga enzima u metabolizmu ugljikohidrata pri diferencijaciji staničnih linija šećerne repe

Plant development is influenced by changes in the levels and types of sugars produced metabolically. The normal (N), habituated organogenic (HO) and habituated nonorganogenic (HNO) sugar beet cell lines originate from the same mother plant but exhibit distinct levels of morphogenesis and differentiation, and contain different levels of simple carbohydrates. We aim to elucidate whether differences in the abundance and activity of enzymes involved in carbohydrate metabolism and sugar sensing/signalling help explain the different carbohydrate profiles and differentiation states of the cell lines. Using 13C NMR spectroscopy to analyze cultures of the cell lines over 28 days, we found that N cells accumulated sucrose; HO cells sucrose, glucose and fructose; and HNO cells glucose and fructose. Of three invertase isoforms, the activity of cell wall invertase (CWI) was highest in all the cell lines, and CWI activity was greatest in HNO line. The specific accumulation of intracellular carbohydrates during subculture correlated strongly with CWI activity but less so with the vacuolar and cytoplasmic invertase isoforms, or with sucrose synthase activity. Cell lines showed differences in how sugars regulated invertase and sucrose synthase activity. The role of sugar sensing in the regulation of CWI activity was investigated in the cell lines using glucose and sucrose, as well as carbohydrate analogues such as mannitol, 2-O-deoxyglucose and 3-O-methylglucose. Differences in the regulation of CWI activity by carbohydrates across the three cell lines suggest that CWI can be fine-tuned according to the specific carbohydrate requirements of each line during growth. Differences in sugar signalling pathways across the cell lines were explored using glucose and sucrose in the presence of inhibitors of protein kinases or phosphatases. Taken together, our findings suggest that specific regulation of CWI activity plays an important role in determining the intracellular carbohydrate levels of sugar beet cell lines, and possibly their differentiation state as well.Na razvoj biljke utječu promjene razine i tipa proizvedenog šećera. Iako sve stanične linije šećerne repe, i to normalna, prilagođena organogena i prilagođena neorganogena potječu od iste biljke, na različitim su stupnjevima diferencijacije i morfogeneze te sadrže različitu količinu jednostavnih ugljikohidrata. Svrha je rada bila utvrditi može li se razlikama u količini i aktivnosti enzima, koji sudjeluju u metabolizmu šećera te onih u detekciji i prijenosu signala šećera, objasniti razlika u stupnju diferencijacije staničnih linija te u udjelu ugljikohidrata u njima. Primjenom 13C NMR spektroskopije analizirane su stanične linije tijekom 28 dana kultivacije i ustanovljeno je da normalne stanične linije akumuliraju saharozu, prilagođena organogena stanična linija saharozu, glukozu i fruktozu, a prilagođena neorganogena stanična linija šećerne repe glukozu i fruktozu. Od 3 izoformna oblika invertaze najveća je aktivnost invertaze stanične stijenke u sve 3 stanične linije, osobito u prilagođenih neorganogenih stanica. Specifičnost akumulacije ugljikohidrata u stanici tijekom kultivacije uvelike je ovisila o aktivnosti invertaze stanične stijenke, a manje o onoj vakuolarne i citoplazmatske invertaze te saharoza sintetaze. Šećeri su različito regulirali aktivnost invertaze stanične stijenke i saharoza sintetaze, ovisno o tipu stanične linije. Njihova je uloga istražena pomoću glukoze i saharoze te njihovih analoga, kao što su manitol, 2-O-deoksiglukoza i 3-O-metilglukoza. Utvrđeno je da se aktivnost invertaze stanične stijenke može fino regulirati pomoću ugljikohidrata, ovisno o potrebi staničnih linija za izvorom šećera tijekom rasta. Razlike u putovima prijenosa signala šećera u staničnih linija istražene su pomoću glukoze i saharoze u prisutnosti inhibitora protein kinaza i fosfataza. Na kraju, rezultati autora potvrđuju da specifična regulacija aktivnosti invertaze stanične stijenke ima važnu ulogu u određivanju razine ugljikohidrata u staničnim linijama šećerne repe, a možda i stupnju diferencijacije stanica