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We study the self-collimation phenomenon in photonic crystals (PhC) of wide bandgap materials for ultra-fast and high spatial resolution x-ray detection. We work on various heavy inorganic scintillators: BaF2, GaN, ZnO, CsI:Tl, NaI:Tl, LYSO, WO4 compounds, and plastic scintillators. Conventional scintillator detectors do not rely on a direct detection mechanism; hence, they require intricate design and fabrication processes. We offer a PhC design to observe self-collimation phenomena and overcome the ongoing spatial resolution challenges with these types of materials. We investigate the photonic band diagrams and iso-frequency contours. Fourier transforms based on finite-difference time-domain and frequency domain simulations are done for verifying and analyzing the self-collimation with the selected material. Light extraction efficiency at the PhC–air interface, depending on the truncation distance from the excitation point, is measured. Beam divergence values are calculated at 1 mm propagation distance. The vertical field profiles are obtained to observe the confinement. For the spatial resolution analysis, cross-sectional beam profiles have been examined. Gaussian envelopes are fitted to beam profiles for a consistent data analysis, and full-width-at-half-maximum values are considered. As a result, we theoretically prove and demonstrate the spatially resolved x-ray detection at the sub-micrometer level for a wide range of scintillator materials. [ABSTRACT FROM AUTHOR]

EUnder field conditions, growth parametres like fresh weight and leaf number, superoxide dismutase (SOD), catalase (CAT), ascorbic peroxidase (APX) enzymes in the antioxidant defence sytems are analysed on 12 lines and two cultivars of pea seedlings which are specified as tolerant against cold. Besides the relationship between the protection mechanisms from abiotic stress conditions (change on the antioxidant enzymes) on the pea plant is tried to be revealed. In terms of macro and microelement accumulation, considering control plants, the effect of low temperature application is not observed in Mn, Mg, Cu microelements. However, approximately ten times decrease is observed on Fe and Zn accumulations. It is also observed that there is not a change on K and Ca accumulation of the plants considering control plants. It is seen that with the low temperature application, there are significant increases on CAT, APX and SOD enzyme activities which are among the antioxidant enzymes of the plants. [ABSTRACT FROM AUTHOR]

Salt stress-induced changes in antioxidant enzymes, such as catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR), total chlorophyll content, and lipid peroxidation measured as malondialdehyde (MDA) content, in leaves of a green bean genotype Gevas sirsk 57 (GS57) and cv. Fransiz 4F-89 differing in salt tolerance were investigated. Plants were subjected to three salt treatments (0, 50, and 100 mM NaCl) under controlled climatic conditions for 7 days. The salt-sensitive cv. 4F-89 exhibited a decrease in GR activity at all salt treatments, but the salt-tolerant genotype GS57 showed only a slight decrease in GR under 50 mM salt treatment and an increase under 100 mM salt treatment. CAT and APX activities increased with increasing salt stress in both varieties. CAT and APX activities were higher in the salt-tolerant GS57 than salt-ensitive cv. 4F-89. The two varieties showed an increase in MDA content with an increase in salinity, but the increase in sensitive cv. 4F-89 under salt stress was higher than that in salt-tolerant GS57 genotype. The increasing NaCl concentration caused a reduction in the chlorophyll content in cv. 4F-89 but not in GS57. [ABSTRACT FROM AUTHOR]

Objective. To quantify luting cement at the crown–tooth interface of esthetic crowns fabricated using four different techniques and two methods of excess cement removal. Material and Methods. Four methods of crown fabrication were used: the feldspathic porcelain and platinum foil technique, the feldspathic porcelain and refractory die technique, the resin composite crown and CAD/CAM technique, and the feldspathic porcelain crown and CAD/CAM technique. Half of the cemented crowns were allocated to Group A: removal of excess cement by flicking-off with a plastic instrument 3 min after initial polymerization, or Group B: removal of excess cement using a wiping action with cotton pellets. Morphologic measurements, using non-destructive digital profilometry, were made of the volume of excess cement (mm 3 ), mean maximum and mean depth of excess cement (µm), and surface area of excess cement (mm 2 ). Results. ANOVA and Duncan post-hoc tests revealed no statistical differences ( p < 0.05) between the four types of crown fabrication with respect to volume and mean depth of retained luting cement. There was a significantly greater volume, mean depth, and mean maximum depth of luting cement retained using the ‘‘flick off’’ method compared to the cotton pellet ‘‘wiping’’ method for excess cement removal, but no statistical differences in mean surface area between the two methods. Conclusions. Following removal of excess luting cement, as judged clinically, using two methods, subclinical amounts of cement remained adherent to the tooth surface of all specimens at the crown-tooth interface. [ABSTRACT FROM AUTHOR]

The National Health Service (NHS) in the UK has witnessed a plethora of changes during the last two decades and although a lot of work has been done in the area of clinical outcomes and effectiveness, very little has been undertaken in the area of managerial effectiveness. The European Centre for Total Quality Management has conducted a research project involving NHS Trusts throughout England and Wales to determine whether organizational effectiveness is a result of management processes, people, or a combination of both. The project included a survey of NHS Trusts based on a self-assessment questionnaire which assessed 10 key areas: strategic development, business planning, marketing and communications, interagency partnerships, performance management, financial management, corporate governance strategy, clinical effectiveness development, activity/demand management and corporate governance. An Organizational Effectiveness model was then developed to 'audit' the responses to the questionnaires and 'drill down' to best practices which produce improved performance. This paper presents the major findings of this research project, and discusses the best practices for performance excellence in the NHS Trusts in the specific areas of management style and structure. [ABSTRACT FROM AUTHOR]

As the pace of change accelerates in the 21st Century as a result of technological opportunities, liberalization of world markets, demands for innovation, quality and speed, organizations have to readjust and realign their operations to counter all these challenges. The pace of change has increasingly forced organizations to be more outward looking, market oriented and knowledge driven. A useful tool that can help businesses build strong capabilities, ensure an inward flow of ideas and establish true competitive gaps is benchmarking. This paper presents the findings of a global survey, undertaken by the European Centre for Total Quality Management (UK), which was aimed at assessing the trends and future directions of benchmarking and the transfer of best practices. Overall, 227 organizations took part in the study. Participant organizations came from 32 different countries, all involved in benchmarking. The participants had a wide cross-section of organizational sectors, ranging from non-profit and government agencies to environmental management services and auto parts manufacturers. The survey shed light on current trends in benchmarking (its spread and the benefits achieved) and highlighted some issues that will affect its future, mainly the effects of information technology and globalization. These factors were seen as an opportunity rather than threat by most study participants. The paper provides an analysis of these results and provides recommended best practices for achieving competitive advantage through benchmarking in the future. [ABSTRACT FROM AUTHOR]

Introduces a framework for the transfer of best practices derived from an analysis of successful case studies. Discussion on benchmarking or best practice management; Concept of a best practice; Details on best practice transfer process; Critical factors for the effective transfer of best practices.

Evaluates the application of total quality management (TQM) and business process re-engineering (BPR) as organizational development models for businesses and companies. Arguments for and against TQM and BPR; Comparison between TQM and BPR; Integration of TQM and BPR; Proposed model for business performance excellence.

Since the early 1990s, there has been an organizational race to implement business process re-engineering (BPR). Many BPR methodologies and variations have been proposed by both academicians and practitioners, but a close look at the concept of BPR emerged from observing the practices of highly successful organizations in the 1980s and early 1990s. Thus, to understand truly BPR one has to learn from the world of organizational experience. It is vital to look at what others have done, their feedback, mistakes, results and overall approach to re-engineering. This paper provides a critical review of 79 case studies from the re-engineering literature. It introduces a review of a wide spectrum of case studies, studying the various approaches, methodologies and tools applied to assess the applicability of BPR concepts universally, the applicability within different organizational types and sectors, the actual results achieved, and the critical success factors and major challenges from the viewpoint of practitioners. [ABSTRACT FROM AUTHOR]

In this paper, we study the spin-bosonic model, with and without tunneling terms, in detail. The spin-bosonic model without tunneling is studied by using the thermofield dynamics approach. Indeed, by considering temperature, we show that environmental states, while they become entangled with system, approach thermal coherent states with different phases. In addition, by considering the tunneling term, we study the interplay of the environmental cut-off frequency as well as the impacts of environmental temperature on the quantum speed limit in both cases, i.e., spin-boson system with and without tunneling term. In these studies, we indicate temperature play more important role in compare with cut-off frequency to control the quantumness of a spin system. [ABSTRACT FROM AUTHOR]

The prevalence of obesity among children and adolescents has been rapidly increasing in recent years. Obese individuals are at risk of vitamin D deficiency. The aim of this study was to investigate the relationship between vitamin D deficiency and anthropometric measurements, cardiovascular risk factors, and glucose homeostasis in obese children. Between June 2011 and January 2012, 40 obese and 30 non-obese children (between 7 and 14 years of age) were evaluated at Tepecik Training and Research Hospital. The following characteristics were recorded: height; weight; body mass index (BMI); total body fat content; fasting glucose, insulin, and lipid levels; basic biochemical parameters; complete blood count; bilateral carotid intima media thickness; liver ultrasound results; and left ventricular wall thickness were recorded. 25-hydroxy (OH) vitamin D levels were measured from serum. The serum 25(OH) vitamin D level was low in 45 children (64.3%). The 24-h ambulatory blood pressure measurements, carotid intima-media thickness, and the prevalence of 25(OH) vitamin D deficiency were different between obese and non-obese children (P < 0.05). The incidence of dyslipidemia was not statistically different between obese and non-obese children (P > 0.05). Plasma 25(OH) vitamin D concentrations were negatively correlated with age, BMI, total body fat content, 24-h ambulatory blood pressure, and carotid intima-media thickness (P < 0.05). Plasma 25(OH) vitamin D levels were not correlated with fasting plasma glucose, HOMA-IR, triglycerides, total cholesterol, low-density cholesterol, and high-density cholesterol (P > 0.05). Vitamin D deficiency is more prevalent in obese children. Serum 25(OH)vitamin D was significantly associated with several cardiometabolic risk factors. There was no relationship between abnormal glucose homeostasis and dyslipidemia with vitamin D deficiency in obese children. [ABSTRACT FROM AUTHOR]

Abstract: A smoke-derived butenolide, 3-methyl-2H-furo[2,3-c]pyran-2-one, has previously been shown to improve seedling vigour of various crop species. The aim of this study was to examine the effect of butenolide priming treatments on seedling emergence and growth when it is applied to peat moss in which seeds are sown (post-sowing) rather than pre-sowing imbibition of the seed itself. Pepper (Capsicum annuum L.) and salvia (Salvia sp.) seeds were sown in peat moss in modules and subjected to either butenolide priming (10−7 M, 25°C) or water for 24h at 25°C in the dark. Following this technique, seeds are imbibed, not subsequently dried and placed in a growth cabinet at 18°C for germination. Butenolide-primed seeds emerged faster (lower MGT) and produced larger seedlings as indicated by fresh and dry weight compared to the water controls for both species. Butenolide-primed seeds had higher catalase activity than that of the controls suggesting that the enhancement obtained from priming may be due to changes in enzymatic activity. Butenolide priming may be used to enhance pepper and salvia seedling performance via the sowing medium. [Copyright &y& Elsevier]

We report on rotaxanes featuring a pyridyl-acyl hydrazone moiety on the axle as a photo/thermal-switchable macrocycle binding site. The pyridyl-acyl E-hydrazone acts as a hydrogen bonding template that directs the assembly of a benzylic amide macrocycle around the axle to form [2]rotaxanes in up to 85% yield; the corresponding Z- hydrazone thread affords no rotaxane under similar conditions. However, the E-rotaxane can be smoothly converted into the Z-rotaxane in 98% yield under UV irradiation. The X-ray crystal structures of the E-and Z-rotaxanes show different intercomponent hydrogen bonding patterns. In molecular shuttles containing pyridyl-acyl hydrazone and succinic amide ester binding sites, the change of position of the macrocycle on the thread can be achieved through a series of light irradiation and heating cycles with excellent positional integrity (>95%) and switching fidelity (98%) in each state. [ABSTRACT FROM AUTHOR]

A smoke-derived butenolide, 3-methyl-2H-furo[2,3-c]pyran-2-one, has previously been shown to improve seedling vigour. The aim of this study is to examine the effect of hydropriming and butenolide priming treatments on seedling emergence and growth under different sowing depths at 20 and 25°C in two melon (Cucumis melo L.) seed lots of high and low quality. Seeds are subjected to hydropriming (21 h at 25°C) and butenolide priming (10-7 M, 21 h at 25°C) and sown at a depth of 4 or 8 cm in peat moss (field capacity, 64% water by mass). In general, seedlings from butenolide-primed and hydroprimed seeds are superior to those of the control. At 20°C, the effect of butenolide priming is more pronounced than that of hydropriming and the control, particularly for the seeds sown at a depth of 8 cm. Butenolide priming has a 'repair-inducing' effect and enhances the low-quality seeds more than those of the high-quality seed lot, an effect which is more obvious at 20°C than 25°C. It can be concluded that butenolide priming may be a useful tool to enhance melon seedling performance under low temperature sowing conditions. [ABSTRACT FROM AUTHOR]