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Power system operation became a challenging with the integration of variable and uncertain Renewable Energy Sources (RES) generation. The operational flexibility describes the technical ability of the power system to respond to the net-load within a controllable power at a certain time to accommodate the RES power output. The main objective of this paper is to analyse and evaluate the impact of the variation of ramping and capacity weights on the flexibility quantification of the IEEE RTS-96 test system. This paper contributes to the up-rising field of flexibility by providing a precise analysis of a deterministic metric and weights variation to assets the available flexibility from the individual generator and as well as when aggregated within the power system. The analysis is executed using a deterministic metric with an iterative variation of both ramping and capacity weights simultaneously to quantify the technical flexibility of the overall system and each different technology of the test system. The results demonstrate that the increment of the capacity weight has more influence on the individual generators flexibility and the overall system flexibility as well. The incremental rate of flexibility is not linear for all the units at the test system. This metric is useful for the power system operators and planners who requires simple, fast and offline metric to quantify the technical flexibility of the power system.

Bacterial lipopolysaccharide (LPS) also known as endotoxin, which represents the outer cell wall membrane of gram-negative bacteria has been implicated as the major bacterial bone-resorbing factor. Recently, the most prevalent form of clinically significant osteopenia and osteoporosis involves periodontitis and otitis media by \ud gram-negative bacteria. The aim of the study is to evaluate circulating endotoxin levels and to study the association amongst endotoxin and bone turnover markers in a cohort of Saudi postmenopausal women with or without osteoporosis. We determined the levels of endotoxin, bone turnover markers, 25-OH vitamin D total and corrected calcium in 100 Saudi postmenopausal women with osteoporosis and 100 women without osteoporosis were taken under the supervision of qualified physicians in the primary care centers in Riyadh. Serum endotoxin, NTx, osteocalcin, PTH, 25-OH vitamin D total and calcium were analyzed. Serum NTX and PTH levels in patients with osteoporosis were significant higher than controls. Serum endotoxin was significantly and positively associated with calcium in all subject and controls. Endotoxin was positively associated with NTX in both groups but not with osteocalcin, PTH or 25-OH vitamin D. Findings of the present study implicate a role for endotoxin-mediated inflammation in patients with osteoporosis.

Unit Commitment (UC) plays a key role in power system operation and control. With the integration of the Renewable Energy Sources (RES) into the power systems, many researchers are still investigating their effects in the UC. This paper presents an improved priority list method for solving the UC with the integration of RES, solar and wind. Coherent operation of RES with the conventional thermal generator is a big challenge thus generation schedule must satisfy the demand under the system constrain and uncertain RES power output. The improved priority list solves the UC problem under the integration of RES power generation. Numerical results are stated and discussed for the effect of solar and wind power integration into the power system. The results demonstrate a significant reduction in the hourly operation cost and start-up cost as well.

Background: Overweight adults are at increased risk for cardiovascular disease and vitamin D deficiency, whereas an important feature to vitamin D physiology is its sex dependence. The aim of this study was to examine whether vitamin D status improvement exerts a sexually dimorphic effect on serum proteins associated with cardiovascular risk among overweight adults. Materials and methods: Unprocessed serum from age- and BMI-matched men (n = 26) and premenopausal women (n = 24) with vitamin D deficiency and after they achieved sufficiency through a 12-month nutritional intervention was analysed using our previously published depletion-free quantitative proteomics method. Key findings were verified with ELISA. Differentially expressed proteins were subjected to in silico bioinformatics assessment using principal component analysis, hierarchical clustering and Metacore™ pathway analysis. All mass spectrometry proteomic data are available via ProteomeXchange (identifier: PXD003663). Results: A total of 282 proteins were differentially expressed after the intervention between men and women (P-value ≤ 0·05), in which the blood coagulation pathway was significantly enriched. In agreement with the proteomics findings, ELISA measurements showed vitamin K-dependent protein C, von Willebrand factor, fibrinogen gamma chain and multimerin-1 proteins, of relevance to blood coagulation, to be differentially affected (P-value ≤ 0·05) between sexes after vitamin D status correction. Conclusions: This study identified novel protein-level molecular indicators on the sexually dimorphic effect of vitamin D status correction associated with blood coagulation among overweight adults. These sex-mediated vitamin D effects should be factored in the design and interpretation of vitamin D observational and interventional studies testing cardiometabolic outcomes. © 2016 Stichting European Society for Clinical Investigation Journal Foundation

In the context of low carbon power systems, the penetration levels of Renewable Energy Sources (RES) are expected to increase dramatically. In this regard, this paper investigates the maximum RES penetration level constrained by net load while considering an inflexible Unit Commitment (UC) model. To solve the UC problem, an enhanced priority list (EPL) based method is developed. In the proposed method, the plants were activated sequentially based on the operational price. The system constraint violations were repeatedly corrected until all system constraints (such as net load and spinning reserves) were satisfied. The proposed EPL method was efficient to achieve a near optimal solution under high shares of RES. Furthermore, the research work investigates three different scenarios representing penetration levels of 10% solar-only, 14.5% wind-only and 27.5% mixture of both solar and wind. The impact of each penetration level on the system scheduling and operational cost were analyzed in detail. The analysis presented shows that a potential operational cost savings of 21.6 $/MW, 20 $/MW and 11.1 $/MW is feasible under each of the represented scenarios, respectively.

In a broad sense, inflammation can be conveniently characterised by two phases: the first phase, which is a pro‐inflammatory, has evolved to clear infection and/or injured tissue; and the second phase concerns regeneration of normal tissue and restitution of normal physiology. Innate immune cell‐derived pro‐inflammatory cytokines and chemokines activate and recruit nonresident immune cells to the site of infection, thereby amplifying the inflammatory responses to clear infection or injury. This phase is followed by a cytokine milieu that promotes tissue regeneration. There is no absolute temporal distinction between these two phases, and cytokines may have dual pleiotropic effects depending on the timing of release, inflammatory microenvironment or concentrations. IL‐22 is a cytokine with reported pro‐ and anti‐inflammatory roles; in this review, we contend that this protein has primarily a function in restitution of normal tissue and physiology.

Objective The aim of the study was to assess the safety and efficacy of epithelium-off corneal cross-linking versus epithelium-on cross-linking in the treatment of keratoconus. Patients and methods This study was performed on 42 eyes of 22 patients who were divided into two groups. The first group was the epithelium-off cross-linking (CXL) group that included 23 eyes of 12 patients, whereas the second group was the epithelium-on cross-linking group (the TECXL group) that included 19 eyes of 10 patients. Results On comparing the effect of epi-off and epi-on we found that epithelium-on CXL is superior to epithelium-off CXL regarding pain, complications, early patient convalescence as we found significant difference between epi-on and epi-off groups in postoperative complications. In epithelium-on CXL regarding eight (42%) eyes had pain, 0 eye had delayed reepithelization, one (5.26%) eye had stromal haze, and six (31.57%) eyes had treatment failure. However, epithelium-off CXL is superior to epithelium-on CXL regarding the efficacy in visual stabilization and improvement as we found a significant improvement in anterior elevation and Kmax with P = 0.04 and 0.02, respectively. Epithelium-off CXL had significant reduction in Kmax with P = 0.03, anterior elevation had significant reduction with P = 0.04 epithelium-on CXL having nonsignificant change in Kmax and anterior elevation. Conclusion Actually, in this study, it was found that TECXL was the procedure of choice for patient comfortability, safety, and convalescence. However, the results of the study confirmed that epithelium-off CXL was the procedure of choice for the patient benefit and guaranteed visual stabilization and additional visual improvement convalescence.

This study examine the effects of heavy metal pollutants to aquatic ecosystems and the environment by considering the role of urban, municipal, agricultural, industrial and other anthropogenic processes as sources of heavy metal pollution in surface water sources of Kaduna metropolis. Samples of the polluted water were collected from River Kaduna and along the Kakuri – Makera drains. The X – Ray florescence (XRF) was used as an analytical technique for the detection of heavy metals (Lead {Pb}, Arsenic {As}, Iron {Fe}, Chromium {Cr}, Copper {Cu} and Zinc {Zn}). The results shows the concentration of most of the heavy metals were higher than WHO (1997) acceptable limits. It is concluded that the water from the river is polluted and may cause serious ecological and health hazards. It is recommended among other things that there should be proper monitoring of effluents into receiving water as an integral part of water management in the river to enable verification of whether or not imposed standards and regulations are met.Keywords: Heavy Metal, Pollutant, World Health Organization (W.H.O) Standards, X – Ray florescence (XRF), Surface Water and Kaduna

Postmenopausal osteoporosis is characterized by rapid bone loss occurring in the post-menopausal period. The bone loss predominantly involves the trabecular bone and is brought about by an imbalance between the bone remodeling process which can be influenced by factors that could cause or contribute to osteoporosis. Pro-inflammatory cytokines (Il-1β, Il-6, IL-8 and TNF-α) have been implicated in the regulation of bone cells and play a critical role in bone remodeling. They act both directly and indirectly to increase bone resorption, and/or inhibit bone formation. The aim of the study is to determine whether pro-inflammatory cytokines correlate with bone turnover markers (BTM) in a cohort of Saudi post-menopausal women with or without osteoporosis and which BTMs will correlate with PTH and Vitamin D for use in osteoporosis diagnosis. The study is composed of 100 post-menopausal patients and 100 controls aged around 50 years. Serum concentrations of pro-inflammatory and BTMs as well as PTH and vitamin D were determined by ELISA, Luminex and electrochemiluminescence. Serum calcium, phosphorus, glucose, and lipid profile were measured by using a chemical analyzer. There was a significant increase in the levels of pro-inflammatory cytokines, PTH, CTx, and glucose. A significantly lower vitamin D and osteocalcin levels were observed in subjects with osteoporosis than those without. No significant differences were recorded in the circulating lipid profile between groups. The present study proved that the pro-inflammatory cytokines accelerate the bone loss in postmenopausal women.

This study assessed agricultural land-use change in Kaduna metropolis. This study combined the use of remote sensing and geographic information system (GIS) application to ascertain the rate of agriculturalland-use change from 1980 to 2012 in the study area. The four imageries (Landsat MSS 1980, Landsat TM 1990, Landsat ETM+ 2005 and Nigeria Sat X 2012) used were classified and compared to understand the rate and extent of agricultural land-use change during the different periods. The findings revealed that the study area experienced a significant reduction inagricultural land and these leads to continued disappearance of farmlands. Lastly, the decrease in agricultural lands leads to loss of livelihood, reduction in food supply and increase poverty. This has raised so many concerns about the sustainability of Urban and Peri Urban Agriculture (UPA) production in the study area whereby the small scale farmers are the most affected.Key Words: Land-Use, Urban, Farmers, Remote Sensing, Geographic Information System (GIS) and Kaduna, Nigeria

OBJECTIVES If they do not respond to other treatments, patients with Budd-Chiari syndrome are potential candidates for a liver transplant. Timing for transplant is controversial; however, before other systems deteriorate, early intervention in relatively stable patient may improve the outcome and survival of these patients. MATERIALS AND METHODS Six patients (2 women and 4 men) had Budd-Chiari syndrome (1.2%) among 475 patients who had undergone a liver transplant at our center between 2001 and 2012. Imaging modalities including duplex ultrasound, abdominal computed tomography angiography, and hematologic evaluation were part of our routine diagnostic work-up. Although we perform mostly living-donor liver transplants, these patients received a liver transplant from a deceased donor, because there was not enough evidence to justify a living-donor liver transplant. We thought that not replacing the caval vein might negatively influence the outcome. Postoperatively, these recipients were started on a heparin infusion and triple therapy immunosuppression; only then was warfarin introduced as long-term anticoagulant. RESULTS Two patients died, 1 from uncontrollable bleeding and disseminated intravascular coagulopathy, and the other died in the intensive care unit after 5 months because of multiorgan failure and sepsis. One patient had portal vein thrombosis 9 months after the liver transplant; the other patient needed a liver retransplant after 5 years owing to liver failure, secondary to chronic rejection. Graft survival rate was 75%, and patient survival rate was 66.6%. CONCLUSIONS This is the first article from Saudi Arabia to describe the outcome of a liver transplant in this subgroup of patients with Budd-Chiari syndrome. Treatment of Budd-Chiari syndrome follows a therapeutic algorithm that should start with anticoagulation and may end up with liver transplant; however, it should be considered early if other treatments fail.

Background: Hypovitaminosis D has been associated with an increased prevalence of Type 2 diabetes mellitus (DMT2) and metabolic syndrome manifestations. The purpose of this study was to examine the association between 25-hydroxy-vitamin D (25-OH-VitD) levels and indices of insulin resistance (IR), including adipocytokines, in a Saudi population with or without DMT2. Subjects and methods: A total of 266 subjects (153 DMT2 and 113 healthy controls) aged 26-80 yr were randomly selected from the existing Biomarkers Screening in Riyadh Program (RIYADH Cohort). Subjects were assessed clinically, anthropometry was performed, morning blood chemistries, including fasting glucose (FG), triglycerides, total cholesterol, LDL cholesterol (LDL-C), and HDL cholesterol were obtained. Homeostasis model assessment of IR (HOMA-IR) was calculated, and serum 25-OH-VitD, leptin, adiponectin, resistin, insulin, high sensitivity CRP (hsCRP), and tumor necrosis factor a concentrations were measured using specific assays. Results: In DMT2 subjects, negative correlations between 25-0H-vitD and body mass index (BMI), FG, insulin, HOMA-IR, cholesterol, LDL-C, and hsCRP were observed, while a positive correlation between 25-OH-VitD and adiponectin was detected. The later remained significant after controlling for BMI. Interestingly, only weak and nonsignificant associations between 25-OH-VitD and metabolic parameters were observed in the control group, whereas, when the entire population was examined, negative correlations were evident primarily between 25-OH-VitD and FG, HOMA-IR, total cholesterol, LDL-C. These associations remained significant after controlling for BMI. Conclusions: These results suggest that hypovitaminosis D associations with metabolic disturbances are accentuated in DMT2. The BMI-independent positive correlation between 25-OH-VitD and adiponectin suggests a potential role for this adipocytokine as a link between 25-OH-VitD and IR in patients with DMT2. (J. Endocrinol. Invest. 36: 1-6, 2013) (C) 2013, Editrice Kurtis

Recent studies in the Middle East have shown an increased incidence of vitamin D deficiency across this region of year-round sunlight. There is scarcity of information, however, as to the levels of 1,25-dihydroxyvitamin D [1,25(OH)(2)D], the active form of vitamin D, and its associations with cardiometabolic parameters in an Arab cohort and this study aims to fill this gap. In a cross-sectional study, 33 male and 43 female (22 children and 54 adults, total 76) Saudis with previously established low levels of serum 25-hydroxyvitamin D [25(OH)D] (

Objective: To analyze long term results of temporal lobe epilepsy surgery without invasive recording and to evaluate preoperative factors predicting good postoperative outcome. Methods: Between October 2000 and October 2007, a total of 125 patients underwent resective surgery for pharmacologically[for full text, please go to the a.m. URL], 60. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit den Benelux-Ländern und Bulgarien

The study aims to investigate the relationship between psychological resiliency and trauma, conduct disorder, PTSD, and neurosis. As well as knowing the level of resiliency among the high school students and to explore the effect of socioeconomic and demographic variables, the type of study, and the religiousness on the level of resiliency. It is analytical descriptive study for 500 children at 6 six different schools inGazacity and north ofGazastrip. The researcher used five questionnaires to see the relation between resiliency and other factors like trauma, PTSD, conduct disorder and neurosis. The results showed that there is a relation between resiliency and conduct disorder, and no relation between resiliency and PTSD, trauma and neurosis. The rate of psychological resiliency was 64.5% which can be considered satisfactory. The results showed also that there is relation between gender and resiliency in favor of females. There is also relation between resiliency and place of residence in favor of the citizens of camps. There is also relation between resiliency and the income rate of the high school students where as the resiliency was in favor of the students whose families' income more than 2000NIS. In the contrast there is no relationship between resiliency and the religiousness and the type of the study. The researcher finally recommends increasing the awareness raising regarding the resiliency and to establish a scientific center specialized in resiliency to be a reference to the people and meant sides that interested in this field.

This paper discusses an actual case that occupational (industrial) hygienists may encounter during their professional career. The case involves establishing a cause and effect relationship of a medical condition that had already taken place in the past. An approach is discussed where an attempt was made to reconstruct the workplace environment within which the medical condition in question may have occurred.