On Generalized Recurrent Finsler Spaces of Higher Order with Berwald’s Curvature Tensor

In this present paper, we introduced a Finsler space Fn which projective curvature tensor K^i_ijkh satisfies the generalized five recurrence property with respect to Berwald’s connection parameters G^i_kh, we have derived some theorems and some identities along with few more related results in a recurrent and generalized 5-recurrent Finsler space with Berwald’s curvature tensor field

Effect of Preheating on the Permeability of Neonatal Rat Stratum Corneum to Alkanols

We heated flat sheets of neonatal rat stratum corneum for various times at temperatures between 40 and 90°C before determining the permeability coefficient (Kp) of propanol and/or hexanol from water. Below 70°C, Kp remained constant; at 75°C, Kp increased linearly with exposure time; at 80°C and above, there was a large increase in under 2 h, with no further increase on longer heating. There was a 15-fold increase in 6-h Kp between 70°C and 80°C, values being constant above 80°C but at a figure less than for lipid-extracted stratum corneum. Thermal analysis showed that the increase in Kp corresponds to changes in the 80°C lipid endotherm, suggesting that the increased Kp is due to a disordering of the lipid structures. The effect of treating preheated stratum corneum with dimethylsulfoxide (DMSO) vapor for 16h was also studied. Below 70°C, Kp was increased five-fold, but between 70 and 80°C this difference was eliminated, so that above 80°C the Kp was the same as with heat treatment alone. We concluded that both heat and DMSO affect the lipid structures of stratum corneum. DMSO produced a small, reversible structural change, while the effect of heat is irreversible and produces a greater degree of disorder in the lipid structures, but the lipid still contributed to the barrier effect of stratum corneum

A LINEAR-PROGRAMMING MODEL TO EVALUATE GAS AVAILABILITY FOR VITAL INDUSTRIES IN SAUDI-ARABIA

Saudi Arabia has realized the huge potential in its natural gas resources and has therefore developed petrochemical industries which utilize the various gas components as their input. Natural gas is associated with oil production, a glut in the oil market reduces the oil production quota and hence the supply of gas (mainly methane and ethane) to these industries. The objective of this paper is to study the impact of oil production on the gas supply to vital industries in Saudi Arabia and determine the minimum level of oil production which sustains its industries. This is achieved by developing a linear programming model for oil production, gas processing and distribution for Saudi Arabia. The model integrates oil fields, gas separator plants, gas plants, fractionation plants and the petrochemical industry. The model optimizes the allocation of oil production to different oil fields while satisfying other vital constraints such as target production of different types of crudes. The results show that a production level of 4 million barrels per day enables Saudi Arabia to satisfy the current demands for methane and ethane

A LINEAR-PROGRAMMING MODEL TO EVALUATE GAS AVAILABILITY FOR VITAL INDUSTRIES IN SAUDI-ARABIA

Saudi Arabia has realized the huge potential in its natural gas resources and has therefore developed petrochemical industries which utilize the various gas components as their input. Natural gas is associated with oil production, a glut in the oil market reduces the oil production quota and hence the supply of gas (mainly methane and ethane) to these industries. The objective of this paper is to study the impact of oil production on the gas supply to vital industries in Saudi Arabia and determine the minimum level of oil production which sustains its industries. This is achieved by developing a linear programming model for oil production, gas processing and distribution for Saudi Arabia. The model integrates oil fields, gas separator plants, gas plants, fractionation plants and the petrochemical industry. The model optimizes the allocation of oil production to different oil fields while satisfying other vital constraints such as target production of different types of crudes. The results show that a production level of 4 million barrels per day enables Saudi Arabia to satisfy the current demands for methane and ethane

Effect of relining, cement type, and thermocycling on push-out bond strength of fiber reinforced posts.

Statement of the problem: Improving the adaptation of fiber reinforced posts through relining may affect the retention of the posts. Purpose: To investigate the effect of post relining, cement type, and thermocycling on the push-out bond strength of fiber reinforced posts. Materials and methods: (48) endodontically treated human teeth were excessively flared using diamond stones. The teeth were divided into two groups; group (1) (n ¼ 24) received glassix glass fiber posts adapted to the flared canals by relining with composite resin and group (2) (n ¼ 24) received non-relined glassix glass fiber post. Samples of each group were divided into three subgroups (n ¼ 8) according to the type of cement used; subgroup (a): luted using Metacem Refill, a total etch resin cement, subgroup (b): luted using Rely X Unicem, a self-adhesive resin cement and subgroup (c): luted using RelyX Luting, a resin modified glass ionomer cement. Half the samples of each subgroup (n ¼ 4) were subjected to thermocycling. The samples were sectioned horizontally into 2 mm thick slices yielding 3 sections for each sample. Retention was evaluated using push out bond strength test using universal testing machine. The maximum failure load was recorded and used to calculate the push-out bond strength. Data was statistically analyzed and mode of failure was assessed using magnifying glass. Results: Relined posts showed statistically significantly higher mean push-out bond strength than non-relined posts. Rely X Unicem showed the statistically significantly highest mean push-out bond strength among tested cements. Metacem showed significantly lower mean push-out bond strength than Rely X Unicem. Rely X Luting showed the statistically significantly lowest mean push-out bond strengths. There was no statistically significant difference between mean push-out bond strength with and without thermocycling. Most failures occurred at the cementedentin interface in the relined group, while adhesive failure occurred at the cement-post interface in non-relined group

Incidence of hip fracture in Saudi Arabia and the development of a FRAX model

Summary A prospective hospital-based survey in representative regions of Saudi Arabia determined the incidence of fractures at the hip. The hip fracture rates were used to create a FRAX® model to facilitate fracture risk assessment in Saudi Arabia. Objective This paper describes the incidence of hip fracture in the Kingdom of Saudi Arabia that was used to characterize the current and future burden of hip fracture, to develop a country-specific FRAX® tool for fracture prediction and to compare fracture probabilities with neighbouring countries. Methods During a 2-year (2017/2018) prospective survey in 15 hospitals with a defined catchment population, hip fractures in Saudi citizens were prospectively identified from hospital registers. The number of hip fractures and future burden was determined from national demography. Age- and sex-specific incidence of hip fracture and national mortality rates were incorporated into a FRAX model for Saudi Arabia. Fracture probabilities were compared with those from Kuwait and Abu Dhabi. Results The incidence of hip fracture applied nationally suggested that the estimated number of hip fractures nationwide in persons over the age of 50 years for 2015 was 2,949 and is predicted to increase nearly sevenfold to 20,328 in 2050. Hip fracture rates were comparable with estimates from Abu Dhabi and Kuwait. By contrast, probabilities of a major osteoporotic fracture or hip fracture from the age of 70 years were much lower than those seen in Abu Dhabi and Kuwait due to higher mortality estimates for Saudi Arabia. Conclusion A country-specific FRAX tool for fracture prediction has been developed for Saudi Arabia which is expected to help guide decisions about treatment

Evidence for a mixed mass composition at the `ankle' in the cosmic-ray spectrum

We report a first measurement for ultra-high energy cosmic rays of the correlation between the depth of shower maximum and the signal in the water Cherenkov stations of air-showers registered simultaneously by the fluorescence and the surface detectors of the Pierre Auger Observatory. Such a correlation measurement is a unique feature of a hybrid air-shower observatory with sensitivity to both the electromagnetic and muonic components. It allows an accurate determination of the spread of primary masses in the cosmic-ray flux. Up till now, constraints on the spread of primary masses have been dominated by systematic uncertainties. The present correlation measurement is not affected by systematics in the measurement of the depth of shower maximum or the signal in the water Cherenkov stations. The analysis relies on general characteristics of air showers and is thus robust also with respect to uncertainties in hadronic event generators. The observed correlation in the energy range around the `ankle' at $\lg(E/{\rm eV})=18.5-19.0$ differs significantly from expectations for pure primary cosmic-ray compositions. A light composition made up of proton and helium only is equally inconsistent with observations. The data are explained well by a mixed composition including nuclei with mass $A > 4$. Scenarios such as the proton dip model, with almost pure compositions, are thus disfavoured as the sole explanation of the ultrahigh-energy cosmic-ray flux at Earth.Comment: Published version. Added journal reference and DOI. Added Report Numbe

Management and outcomes of gastrointestinal congenital anomalies in low, middle and high income countries: Protocol for a multicentre, international, prospective cohort study

Introduction Congenital anomalies are the fifth leading cause of death in children <5 years of age globally, contributing an estimated half a million deaths per year. Very limited literature exists from low and middle income countries (LMICs) where most of these deaths occur. The Global PaedSurg Research Collaboration aims to undertake the first multicentre, international, prospective cohort study of a selection of common congenital anomalies comparing management and outcomes between low, middle and high income countries (HICs) globally. Methods and analysis The Global PaedSurg Research Collaboration consists of surgeons, paediatricians, anaesthetists and allied healthcare professionals involved in the surgical care of children globally. Collaborators will prospectively collect observational data on consecutive patients presenting for the first time, with one of seven common congenital anomalies (oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation and Hirschsprung''s disease). Patient recruitment will be for a minimum of 1 month from October 2018 to April 2019 with a 30-day post-primary intervention follow-up period. Anonymous data will be collected on patient demographics, clinical status, interventions and outcomes using REDCap. Collaborators will complete a survey regarding the resources and facilities for neonatal and paediatric surgery at their centre. The primary outcome is all-cause in-hospital mortality. Secondary outcomes include the occurrence of postoperative complications. Chi-squared analysis will be used to compare mortality between LMICs and HICs. Multilevel, multivariate logistic regression analysis will be undertaken to identify patient-level and hospital-level factors affecting outcomes with adjustment for confounding factors. Ethics and dissemination At the host centre, this study is classified as an audit not requiring ethical approval. All participating collaborators have gained local approval in accordance with their institutional ethical regulations. Collaborators will be encouraged to present the results locally, nationally and internationally. The results will be submitted for open access publication in a peer reviewed journal