8,658 research outputs found
Buffalo Child Care Means Business: Full Study Report
[Excerpt] Buffalo Child Care Means Business presents the economic and business case for making Buffalo\u27s children the focus of economic development. The 2006 survey of 117 businesses located in downtown Buffalo, New York, documents the business sector\u27s present and projected reliance upon high quality child care services as a necessary component to optimum workplace recruitment, productivity and stability. This promising study highlights research specific to the Buffalo region measuring the cost the community bears as a result of low quality child care and early education. It draws upon nationally recognized economic development strategies to offer recommendations for a strategic child care plan integral to the City of Buffalo\u27s overall strategic initiatives to strengthen downtown\u27s attractiveness to successful enterprises.
The early development needs of Buffalo\u27s children must be front and center if the potential economic power of broadly successful education is to be realized. With business, government, education and child care leaders at the table, Buffalo\u27s economic renaissance can be built on individual and social foundations that last a lifetime
Photonic Crystals with Alternate Arrays of Rods and Holes in a Low Dielectric-Index Material
This thesis theoretically deals with the propagation of electromagnetic waves (light beams) in periodically modulated dielectric material structures based on Maxwell’s equations. We are interested in novel light propagation characteristics in these man-made dielectric material structures for practical applications, especially on optical communications and computations. Since the wavelength range of light is on the same order of magnitude as the modulation periods of dielectric materials, an analogy of the light propagation in dielectric-constant modulated structures with the electron transport in solid-state crystals is used throughout my thesis by using a term “photonic crystals (PhCs)” referring to these dielectric structures. I started my work on two-dimensional (2D) PhCs. A new type of PhCs is proposed which consists of alternate arrays of rods and holes (AARH), embedded in a low dielectric-constant material such as ultravioletcurable polymer. By modeling them as 2D PhCs, it is discovered that this type of PhCs exhibits overlapped photonic band gaps (PBGs) for both transverse electric (TE) and transverse magnetic (TM) polarized light beams. This discovery is important for many practical applications related to light manipulation. It opens the door to more effective optical computing elements, as well as 1 better wave guides, LEDs and micro-lasers. It is also found that new AARH PhCs possess many interesting near-band-edge properties such as left-hand-material characteristics manifested by perfect reflection, negative refraction, and superlensing. I then extended my work to three dimensional (3D) counterparts of the discovered PhCs, which are called photonic crystal slabs (PCSs). I found that the overlapped TE and TM PBGs persist in these PCSs although they are restricted to a partial k-space. By manipulating certain structure parameters such as the thickness of PCS and its cladding, it is possible to achieve overlapping incomplete PBGs exactly in the frequency range predicted by 2D simulations. Hence, one can use fast and cheap 2D simulation instead of slow and expensive 3D and still engineer complex 3D photonic structures. The AARH PCSs also exhibit negative refraction and near zero effective refractive index. These effects allow for a strong control over the light propagation in PhCs. Additionally, the edge and surface modes of proposed PCSs are observed that effectively enlarge slabs’ PBGs
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Some new categorical invariants
In this paper we introduce new categorical notions and give many examples. In an earlier paper we proved that the Bridgeland stability space on the derived category of representations of K(l), the l-Kronecker quiver, is biholomorphic to CxH for l >= 3. In the present paper we define a new notion of norm, which distinguishes {Db(K(l))}l >= 2. More precisely, to a triangulated category T which has property of a phase gap we attach a non-negative real number epsilon. Natural assumptions on a SOD T=T1,T2 imply epsilon}. Using the norm we define a topology on the set of equivalence classes of proper triangulated categories with a phase gap, such that the set of discrete derived categories is a discrete subset, whereas the rationality of a smooth surface S ensures that [Db(point)]is an element of Cl([Db(S)]). Categories in a neighborhood of Db(K(l)) have the property that Db(K(l)) is embedded in each of them. We view such embeddings as non-commutative curves in the ambient category and introduce categorical invariants based on counting them. Examples show that the idea of non-commutative curve-counting opens directions to new categorical structures and connections to number theory and classical geometry. We give a definition, which specializes to the non-commutative curve-counting invariants. In an example arising on the A side we specialize our definition to non-commutative Calabi-Yau curve-counting, where the entities we count are a Calabi-Yau modification of Db(K(l)). In the end we speculate that one might consider a holomorphic family of categories, introduced by Kontsevich, as a non-commutative extension with the norm, introduced here, playing a role similar to the classical notion of degree of an extension in Galois theory
Interventions for the Treatment of Cancer-Related Traumatic Stress Symptoms: A Systematic Review of the Literature.
OBJECTIVE: Cancer has been reported to trigger symptoms of post-traumatic stress disorder (PTSD) in a substantial proportion of individuals. Despite the significant burden associated with these symptoms, there are as yet no therapeutic guidelines. This systematic review aims to evaluate the effectiveness of interventions for cancer-related post-traumatic stress in order to provide an evidence base for developing appropriate clinical practice. METHODS: Databases searched until April 2018 included, Psych INFO, EMBASE, Medline and the Cumulative Index to Nursing and Allied Health Literature (CINAHL). No restrictions to study design were applied. Participants aged 18 years or older who received their cancer diagnosis in adulthood and had symptoms of cancer-related PTSD were included. Due to significant clinical heterogeneity, a meta-analysis was not performed. RESULTS: Of 508 unique titles, eight studies met study inclusion criteria: five RCTs, one before-and-after study, one case series and one case study. Interventions were predominately psychological and were administered to patients with a range of cancer types. Eye Movement Desensitisation and Reprocessing and cognitive behavioural therapy-based interventions were associated with reduced symptomatology, however, overall the methodological quality of studies had limitations. CONCLUSIONS: At present there is only weak evidence available for the effectiveness of psychological interventions in reducing symptoms of cancer-related PTSD. The majority of interventions were administered to all cancer patients regardless of whether they showed pretreatment levels of post-traumatic stress. Future studies would be better targeted towards patients with a diagnosis of cancer and who have significant levels of cancer-related post-traumatic symptoms. Higher quality trials are also needed before treatment recommendations can be made
Extraction and Liquid-Membrane Preconcentration of Vincamine from Periwinkle (VincaMinor L.) Leaves. Process Modelling
An integrated process coupling solid-liquid extraction and liquid-membrane preconcentration of vincamine was studied. The effect of the ratios solid phase/extractant volume and extractant volume/liquid membrane volume on the mass transfer rate and
efficiency of vincamine removal were estimated. It was found that the transfer rate and removal efficiency of the alkaloid were higher with smaller quantities of solids and membrane volume. A mathematical description of the overall integrated process was proposed, and the values of the model parameters – mass transfer coefficients – were evaluated.
An agreement between the model-predicted results and the experimental data obtained was demonstrated. The four-phase integrated process provides simultaneously almost complete extraction and appreciable enrichment of the extracted product
Selective recovery of tropane alkaloids applying liquid membrane technique
A tropine recovery from its solutions applying a liquid membrane technique was studied. Among several studied organic solvents, chloroform showed best extraction ability towards atropine. Pertraction studies were carried out in a laboratory bulk liquid membrane contactor with agitation of all three phases. Both, aqueous solutions of pure atropine and extract of Atropa Belladonna L. roots were used as feed solutions, as well as chloroform and diluted sulphuric acid as a liquid membrane and a stripping liquor, respectively. The effect of phase agitation on alkaloid pertraction was studied for the cases when pure atropine solutions were used as feed phase. A pertraction process carried out with native liquid extracts from A. Belladonna provided selective alkaloid recovery and its concentration in the acceptor solutio
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