The Effectiveness of Silane and Siloxane Treatments on the Superhydrophobicity and Icephobicity of Concrete Surfaces

Icy roads lead to treacherous driving conditions in regions of the U.S., leading to over 450 fatalities per year. De-icing chemicals, such as road salt, leave much to be desired. In this report, commercially available silane, siloxane, and related materials were evaluated as solutions, simple emulsions, and complex emulsions with incorporated particulates, for their effectiveness as superhydrophobic treatments. Through the development and use of a basic impact test, the ease of ice removal (icephobicity) was examined as an application of the targeted superhydrophobicity. A general correlation was found between icephobicity and hydrophobicity, with the amount of ice removed on impact increasing with increasing contact angle. However, the correlation was poor in the high performance region (high contact angle and high ice removal.) Polymethylhydrogensiloxane was a top performer and was more effective when used as a shell type emulsion with silica fume particulates. An aqueous sodium methyl siliconate solution showed good performance for ice loss and contact angle, as did a commercial proprietary emulsion using a diethoxyoctylsilyl trimethylsilyl ester of silicic acid. These materials have sterically available functional groups that can react or associate with the concrete surface and are potentially film-forming. Materials with less reactive functional groups and a lower propensity to film-form did not perform as well

Femtosecond carrier dynamics and saturable absorption in graphene suspensions

Nonlinear optical properties and carrier relaxation dynamics in graphene, suspended in three different solvents, are investigated using femtosecond (80 fs pulses) Z-scan and degenerate pumpprobe spectroscopy at 790 nm. The results demonstrate saturable absorption property of graphene with a nonlinear absorption coefficient, $beta$, of ~2 to 9x10^-8 cm/W. Two distinct time scales associated with the relaxation of photoexcited carriers, a fast one in the range of 130-330 fs (related to carrier-carrier scattering) followed by a slower one in 3.5-4.9 ps range (associated with carrier-phonon scattering) are observed.Comment: 3 pages, 2 figures, 2 table

Sclerosing PEComa: A Histologic Surprise

PEComa represents a group of mesenchymal tumors consisting of perivascular epithelioid cells. We present a 50-year old female patient with a rare distinctive variant, sclerosing PEComa, characterized by extensive stromal hyalinization and a predilection for the pararenal retroperitoneum.Key Words: PEComa, Sclerosing PECom

Clinical characteristics and laboratory profile of childhood systemic lupus erythematosus in a tertiary care center

Objectives: To study the clinical characteristics and laboratory profile of systemic lupus erythematosus (SLE) in children in a tertiarycare center. Methods: Children presenting to our tertiary care center with suspected SLE, fulfilling at least 4 out of 11 American Collegeof Rheumatology (ACR) criteria for the diagnosis of SLE were reviewed retrospectively. The study period was from June 2012 to May2015. The clinical presentation and laboratory parameters were analyzed. Results: A total of 14 patients fulfilled the ACR criteria; therewere 12 girls and 2 boys with a sex ratio of 1:6 favoring girls. The mean age on presentation was 9.8 years with a range of 3-15 years.At presentation, 70% of the children had features not suggestive of SLE. The most common symptom was fever seen in 100% of thepatients, followed by hematological abnormalities in 78%, and renal involvement in 57% patients. Arthritis, skin lesions, and pulmonaryinvolvement were seen in 42% of the patients. The gastrointestinal presentation was seen in 21% of the patients. Conclusion: SLE has avaried clinical presentation depending on the predominant organ involved. A high index of suspicion is required for the early diagnosisof SLE in children

LESS-WEIGHT AIRCRAFT WING DESIGN FRAMEWORK USING REINFORCED MATERIAL

The primary number of materials in aircraft construction continues to be wood, steel, aluminum alloys and much more lately, titanium alloys and fiber reinforced composites. Several factors influence selecting material which strength allied to lightness is an essential. Subsonic aircraft can be used as business jets and commercial airplanes. The wings are often straight or with low sweep position. Composite materials are very well recognized for their excellent mixture of high structural stiffness and occasional weight.CFC is viewed to possess a modulus two times &strength three occasions those of aluminum alloy, the traditional materials in aircraft construction. In the studies conducted concerning the fat loss, it's believed that substitute of Al. alloy by CFC leads to 52.96% saving within the total structural weight from the aircraft wing. In our work the aircraft wing components skin is examined thinking about both isotropic and composite materials. The parametric study conducted using MSc Nastran finite element package

Study of sleep problems and their association with scholastic performance in school going children

Background: Sleep is an integral part of any healthy individual and sleep problems can affect the intellectual abilities including theperformance at school. Objectives: We studied the sleep problems among school going children in the age group of 6-16 years and theassociation of the sleep problems with scholastic performance in them. Materials and Methods: The study was a cross-sectional studycarried out in students attending a private school. The children were given a questionnaire based on the “BEARS” screening tool forsleep problems in children to be filled by children and parents. Accordingly, the age and academic grades of students were recorded.The prevalence of sleep problems and their relation to school grades were studied. Results: Out of 229 students, 25.33% (58) studentswere found to have sleep problems after applying the “BEARS” criteria. Of these 58 children, 31 scored A grade, 25 scored B grade, and2 scored C grade. 23% (31 out of 135) of A graders were found to have sleeping problems, 28% (25 out of 89) of B graders, and 40%(2 out of 5) of C graders had sleeping problems. Conclusion: Sleep problems were common in school going children. It was observedthat as scholastic grades decreased, the prevalence of sleeping problems increased. Sleep problems might be one of the contributors forpoor scholastic achievements in children

Minimal descriptors for characterization and evaluation of Jatropha curcas L. germplasm for utilization in crop improvement

Jatropha curcas germplasm collected from peninsular region of India as well as germplasm augmented from various parts of the country was characterized for various agro-morphological traits at 3 locations for 3 years. Variability was evident for 38 traits which included both qualitative and quantitative traits. Important yield influencing traits such as plant canopy, branching habit, number of primary branches, peduncle branching, peduncle length, inflorescence compactness, flower ratio, inflorescence abundance, flowering, fruits per cluster, 100-seed weight and oil content showed a wide range of variability in the germplasm under study. Number of leaf lobes also showed variation and accordingly were categorised as 0–2, 3–5, >6. The branching pattern varied widely and has been categorised as basal, intermediate, top and entire. The male to female flower ratio ranged from 10:1 to >20:1, and was categorized into three categories as 10:1, 11–20:1 and >20:1. The seed oil content which is of commercial importance in J. curcas also exhibited wide variability ranging from 17.5 to 41.6% and the descriptor has been categorized accordingly as 0–20, 21–30, 30–40 and ≥40%. Based on the variability observed in the traits, a set of 38 minimal descriptors has been suggested for characterization and evaluation of Jatropha

Addressing healthcare needs of people living below the poverty line: a rapid assessment of the Andhra Pradesh Health Insurance Scheme

BACKGROUND: Families living below the poverty line in countries which do not have universal healthcare coverage are drawn into indebtedness and bankruptcy. The state of Andhra Pradesh in India established the Rajiv Aarogyasri Community Health Insurance Scheme (RACHIS) in 2007 with the aim of breaking this cycle by improving the access of below the poverty line (BPL) families to secondary and tertiary healthcare. It covered a wide range of surgical and medical treatments for serious illnesses requiring specialist healthcare resources not always available at district-level government hospitals. The impact of this scheme was evaluated by a rapid assessment, commissioned by the government of Andhra Pradesh. The aim of the assessment was to explore the contribution of the scheme to the reduction of catastrophic health expenditure among the poor and to recommend ways by which delivery of the scheme could be improved. We report the findings of this assessment. METHODS: Two types of data were used for the assessment. Patient data pertaining to 89 699 treatment requests approved by the scheme during its first 18 months were examined. Second, surveys of scheme beneficiaries and providers were undertaken in 6 randomly selected districts of Andhra Pradesh. RESULTS: This novel scheme was beginning to reach the BPL households in the state and providing access to free secondary and tertiary healthcare to seriously ill poor people. CONCLUSION: An integrated model encompassing primary, secondary and tertiary care would be of greater benefit to families below the poverty line and more cost-effective for the government. There is considerable potential for the government to build on this successful start and to strengthen equity of access and the quality of care provided by the scheme