An Enhanced Features Extractor for a Portfolio of Constraint Solvers

Recent research has shown that a single arbitrarily efficient solver can be significantly outperformed by a portfolio of possibly slower on-average solvers. The solver selection is usually done by means of (un)supervised learning techniques which exploit features extracted from the problem specification. In this paper we present an useful and flexible framework that is able to extract an extensive set of features from a Constraint (Satisfaction/Optimization) Problem defined in possibly different modeling languages: MiniZinc, FlatZinc or XCSP. We also report some empirical results showing that the performances that can be obtained using these features are effective and competitive with state of the art CSP portfolio techniques

Management of Business Challenges Among Small and Micro Enterprises in Nairobi-Kenya

Small and Micro Enterprises (SMEs) play an important economic role in many countries. In Kenya, for example the SME sector contributed over 50percent of new jobs created in 2005 but despite their significance, SMEs are faced with the threat of failure with past statistics indicating that three out five fail within the first few months. This study sought to understand how SMEs manage the challenges they face. These challenges seem to change (evolve) according to different macro and micro conditions. This study employed stratified random sampling to collect data from 198 businesses using interviews and questionnaires. The data was analysed descriptively and presented through figures, tables and percentages. The findings indicate that SMEs face the following challenges; competition among themselves and from large firms, lack of access to credit, cheap imports, insecurity and debt collection. Credit constraint seems to be easing up when compared to previous researches. Relevant training or education is positively related to business success. The SMEs have the following strategies to overcome the challenges; fair pricing, discounts and special offers, offering a variety of services and products, superior customer service and continuously improving quality of service delivery. The research concludes that business success is a consequence of embracing a mix of strategies

Multimodal ophthalmic imaging of staphylococcus aureus bacteremia associated with chorioretinitis, endocarditis, and multifocal brain abscesses

Purpose: Staphylococcus aureus bacteriemia (SAB) as critical condition for the life and occasionally involves the eyes. The aim of this report is to describe the ocular involvement with multimodal imaging. Observations: A patient admitted for evaluation of acute onset of confusion, disorientation, and generalized malaise and found to have methicillin-resistant staphylococcus aureus (MRSA)-associated endocarditis and multifocal brain abscesses was evaluated by the ophthalmology service. The patient's visual acuity was 20/20 OU without relative afferent pupillary defect and normal intraocular pressures. Bedside anterior segment examination was normal. Posterior segment examination revealed intraretinal hemorrhages and Roth spots in the posterior pole of the right eye, and two deep well-defined focal white chorioretinal infiltrates and a hemorrhagic pigment epithelium detachment in the temporal quadrant of the left eye. Multimodal imaging was utilized to document these findings and ensure adequate antibiotic therapy. Conclusion: SAB has the potential for poor visual outcomes as well as significant morbidity and mortality. Multimodal imaging of SAB-related chorioretinitis allows for accurate diagnosis as well as assessment of response to antimicrobial therapy

Co-polymers of Furan with Pyrrole or Thiophene: A Synthetic Study

The use of conductive polymers as a substitute for metallic conductors and semiconductors has attracted much attention in the literature. In particular, aromatic heterocyclic polymers constitute an important class since they possess chemical and electrical stability in both the oxidized (doped) and neutral (undoped) state. Doping a polymer allows one to vary its electrical, mechanical, optical, and thermal properties. The properties of these polymers are promising for their many technological uses such as antistatic coatings, solar cells, and electronic devises. Polyfuran is among the least common heterocyclic polymers. Polyfuran has been reported to be much less stable that either polypyrrole or polythiophene. The preparation of co-polymers of polyfuran with two percent pyrrole or thiophene is reported. The polymers are characterized by *HNMR, IR, and ESR spectroscopy, and the electrical conductivity of the doped and un-doped synthetic polyfuran and co-polymers is provided

Multimodal imaging in hereditary retinal diseases

Introduction. In this retrospective study we evaluated the multimodal visualization of retinal genetic diseases to better understand their natural course. Material and Methods. We reviewed the charts of 70 consecutive patients with different genetic retinal pathologies who had previously undergone multimodal imaging analyses. Genomic DNA was extracted from peripheral blood and genotyped at the known locus for the different diseases. Results. The medical records of 3 families of a 4-generation pedigree affected by North Carolina macular dystrophy were reviewed. A total of 8 patients with Stargardt disease were evaluated for their two main defining clinical characteristics, yellow subretinal flecks and central atrophy. Nine male patients with a previous diagnosis of choroideremia and eleven female carriers were evaluated. Fourteen patients with Best vitelliform macular dystrophy and 6 family members with autosomal recessive bestrophinopathy were included. Seven patients with enhanced s-cone syndrome were ascertained. Lastly, we included 3 unrelated patients with fundus albipunctatus. Conclusions. In hereditary retinal diseases, clinical examination is often not sufficient for evaluating the patient's condition. Retinal imaging then becomes important in making the diagnosis, in monitoring the progression of disease, and as a surrogate outcome measure of the efficacy of an intervention

Predisposition to Alcohol Drinking and Alcohol Consumption Alter Expression of Calcitonin Gene-Related Peptide, Neuropeptide Y, and Microglia in Bed Nucleus of Stria Terminalis in a Subnucleus-Specific Manner

Excessive alcohol consumption is often linked to anxiety states and has a major relay center in the anterior part of bed nucleus of stria terminalis (BNST). We analyzed the impact of (i) genetic predisposition to high alcohol preference and consumption, and (ii) alcohol intake on anterior BNST, namely anterolateral (AL), anteromedial (AM), and anteroventral (lateral + medial subdivisions: AVl, AVm) subnuclei. We used two rat lines selectively bred for low- and high-alcohol preference and consumption, named Sardinian alcohol-non preferring (sNP) and -preferring (sP), respectively, the latter showing also inherent anxiety-related behaviors. We analyzed the modulation of calcitonin gene-related peptide (CGRP; exerting anxiogenic effects in BNST), neuropeptide Y (NPY; exerting mainly anxiolytic effects), and microglia activation (neuroinflammation marker, thought to increase anxiety). Calcitonin gene-related peptide-immunofluorescent fibers/terminals did not differ between alcohol-naive sP and sNP rats. Fiber/terminal NPY-immunofluorescent intensity was lower in BNST-AM and BNST-AVm of alcohol-naive sP rats. Activation of microglia (revealed by morphological analysis) was decreased in BNST-AM and increased in BNST-AVm of alcohol-naive sP rats. Prolonged (30 consecutive days), voluntary alcohol intake under the homecage 2-bottle “alcohol vs. water” regimen strongly increased CGRP intensity in BNST of sP rats in a subnucleus-specific manner: in BNST-AL, BNST-AVm, and BNST-AM. CGRP area sum, however, decreased in BNST-AM, without changes in other subnuclei. Alcohol consumption increased NPY expression, in a subnucleus-specific manner, in BNST-AL, BNST-AVl, and BNST-AVm. Alcohol consumption increased many size/shapes parameters in microglial cells, indicative of microglia de-activation. Finally, microglia density was increased in ventral anterior BNST (BNST-AVl, BNST-AVm) by alcohol consumption. In conclusion, genetic predisposition of sP rats to high alcohol intake could be in part mediated by anterior BNST subnuclei showing lower NPY expression and differential microglia activation. Alcohol intake in sP rats produced complex subnucleus-specific changes in BNST, affecting CGRP/NPY expression and microglia and leading to hypothesize that these changes might contribute to the anxiolytic effects of voluntarily consumed alcohol repeatedly observed in sP rats

Neovascular glaucoma induced by peripheral retinal ischemia in neurofibromatosis type 1: Management and imaging features

Purpose: To report the case of a young patient affected by neurofibromatosis 1 (NF-1) with peripheral retinal ischemia-induced neovascular glaucoma and the peculiar spectral-domain optical coherence tomography (SD-OCT) features. Material and Methods: A 13-year-old boy affected by NF-1, as diagnosed according to established criteria, was referred with a diagnosis of hypertensive uveitis in his left eye. He underwent a complete ophthalmic examination and comprehensive blood work with viral and immunological tests. The case was documented with fluorescein angiography (FA) and SD-OCT. When the intraocular pressure (IOP) of the left eye decreased and the cornea cleared, FA revealed retinal ischemia and leakage from pathologic retinal vessels. SD-OCT revealed foveal hypoplasia secondary to the complete absence of the retinal nerve fiber layer. Results: Peripheral retinal ischemia-induced neovascular glaucoma was diagnosed. The patient underwent Ahmed valve implantation to control his IOP, and subsequent retinal photocoagulation by argon laser and intravitreal bevacizumab injection were performed to control neovascularization. Discussion: Retinal ischemia in NF-1 might lead to neovascular glaucoma: lowering of the IOP with surgical implantation of an Ahmed valve, regression of neovascularization by argon laser panretinal photocoagulation and intravitreal injection of bevacizumab can be a helpful way to control such a complication

Indocyanine Green Angiography and Optical Coherence Tomography Angiography of Choroidal Neovascularization in Age-Related Macular Degeneration

To compare the capability of indocyanine green angiography (ICGA) and optical coherence tomography angiography (OCTA) in detecting choroidal neovascularization (CNV)

Vacuum Polarization Effects in the Lorentz and PCT Violating Electrodynamics

In this work we report new results concerning the question of dynamical mass generation in the Lorentz and PCT violating quantum electrodynamics. A one loop calculation for the vacuum polarization tensor is presented. The electron propagator, "dressed" by a Lorentz breaking extra term in the fermion Lagrangian density, is approximated by its first order: this scheme is shown to break gauge invariance. Then we rather consider a full calculation to second order in the Lorentz breaking parameter: we recover gauge invariance and use the Schwinger-Dyson equation to discuss the full photon propagator. This allows a discussion on a possible photon mass shift as well as measurable, observable physical consequences, such as the Lamb-shift.Comment: Latex file, 19 pages, no figures, includes PACS number