Analysis and optimization of storage IO in distributed and massive parallel high performance systems

Although Moore’s law ensures the increase in computational power, IO performance appears to be left behind. This minimizes the benefits gained from increased computational power. Processors have to idle for a long time waiting for IO. Another factor that slows the IO communication is the increased parallelism required in today’s computations. Most modern processing units are built from multiple weak cores. Since IO has a low parallelism the weak cores will decrease system performance. Furthermore to avoid added delay of external storage, future High Performance Computing (HPC) systems will employ Active Storage Fabrics (ASF). These embed storage directly into large HPC systems. Single HPC node IO performance will therefore require optimization. This can only be achieved with a full understanding of the IO stack operations. The analysis of the IO stack under the new conditions of multi-core and massive parallelism leads to some important conclusions. The IO stack is generally built for single devices and is heavily optimized for HDD. Two main optimization approaches are taken. The first is optimizing the IO stack to accommodate parallelism. Conclusions on IO analysis shows that a design based on several parallel operating storage devices is the best approach for parallelism in the IO stack. A parallel IO device with unified storage space is introduced. The unified storage space allows for optimal function division among resources for both read and write. The design also avoids large parallel file systems overhead by using limited changes to a conventional file system. Furthermore the interface of the IO stack is not changed by the design. This is a rather important restriction to avoid application rewrite. The implementation of such a design is shown to result in an increase in performance. The second approach is Optimizing the IO stack for Solid State Drives (SSD). The optimization for the new storage technology demanded further analysis. These show that the IO stack requires revision on many levels for optimal accommodation of SSD. File system preallocation of free blocks is used as an example. Preallocation is important for data contingency on HDD. However due to fast random access of SSD preallocation represents an overhead. By careful analysis to the block allocation algorithms, preallocation is removed. As an additional optimization approach IO compression is suggested for future work. It can utilize idle cores during an IO transaction to perform on the fly IO data compression

SALT MINERALS AT WADI EL NATRUN SALINE LAKES, EGYPT. NEW IMPLICATIONS FROM REMOTE SENSING DATA

The salts of Wadi El Natrun saline lakes are made up of sodium chloride (NaCl, halite), sodium sulfate (Na2SO4, thenardite) and sodium carbonate (Na2CO3.10H2O, natron) deposited on the bottom of the Lakes and surrounding sabkhas. The lakes of El Raizonia, Umm Risha, El Fasda, El Beida and El Gaar are the most potential lakes for economic halite salts. Furthermore, El Beida Lake contains Na2SO4 salts, mixed with halite, and Umm Risha and El Fasda lakes are characterized by natron salt showings. The chemical analysis of the saline water revealed dominant Cl-, Na+, Ca2+, CO32-, and HCO3- as major ions; while Mg2+, SO42- and NO3- are defined as minor ions. Chemical analysis of the salt deposits of these lakes shows similarity in the mineral composition with that of the saline water indicating that the water of such lakes is the main source of the realized salt minerals

The influence of gibberellic acid on growth and structure of cotton fibres

This investigation was carried out to find the effect of gibberellic acid on fibre length and consequently the other gross and fine structural, and mechanical, properties of cotton fibres. In the course of investigations some general relationships were discovered which appear to apply to all cotton fibres whether treated or not. Three cotton varieties were used: Samaru 26J and Rex, both Upland varieties, and Sea Island V.H.8 cotton. All three were grown in greenhouse in Glasgow and Samaru 26J was also grown under normal field conditions in Nigeria. Gibberellic acid treatment increased fibre mean length and decreased the coefficient of variation for Rex and Samaru 26J grown in Glasgow, but had no effect on the first two varieties in attributed to an increase in the total number of fibres per seed in Rex. Treatment with gibberellic acid also resulted in a decrease in fibre diameter, fibre weight and linear density, and maturity and fibre density. The number of convolutions per unit length and the average convolution angle were generally lower in the treated samples, this is attributed to the differences in maturity. The number of reversals per unit length was lower in treated than in the control samples this attributed to the increase in the boll size. Gibberallic acid treatment was found to regulate cellulose deposition. This resulted in fibres of different lengths having weight proportional to their length. The stress-strain curves were analyzed and the effect of major weak places was removed to get the extrapolated "projected" stress-strain curves. Gibberellic acid treatment increased the projected extension to break, tensile strength, work of rupture and stiffness of Samaru26 J grown in Glasgow, Rex, and Sea Island, but these improvements were largely offset in practice because of the projected mechanical properties was nil but the number of weak places increased and there was an overall deterioration. Generally, the effect of gibberellic acid dependent on variety and environment. It is more effective on short cottons and under poor grooving conditions than on long cottons and under optimum grooving conditions. The overall molecular orientation has been found to be dependent on both fibre length and fibre diameter. Therefore, a factor (radius/length) has been suggested to describe fibre dimensions. This factor gives high correlation with overall molecular orientation, initial Young's modulus, and stiffness measurements on fibres having successive degrees of wall thickening. It has been shown that the convolutions unfold as load is applied, thus they contribute substantially to fibre extensibility and work of rupture. This contribution varies from sample to sample. The reminder of fibre extension to break is suggested to be due to a partial unfolding of the spiral and to the extension of the amorphous regions located within the spiralling fibrils. The total theoretical extension to break resulting from fibre fine and gross structure is apparently much higher than the measured one

النص القرآني بين إشكالية الفهم ودلالة النص

 النص القرآني نص رباني مقدس، جاء لبيان مراد الله من عباده، وكان النبي - صلى الله عليه وسلم- السبيل الوحيد لبيان ما استُشكل على المسلمين في فهم ألفاظه ومعانيه، ثم رصيد لغوي أصيل يمتلكه المسلمون وقتئذٍ. بيد أن الأمر أصبح عسرا، والطريق إلى فهم مراد القرآن أصبحت غير مُعبَّدةٍ على الرغم من أن الله جعل القرآن ميسرا للذكر. والسبب في هذا الإعسار وفاة النبي - صلى الله عليه وسلم-  من جهة، ثم البون الزمني الشاسع بين وقت نزول القرآن وبداية عصر التدوين الذي قارب قرنين من الزمان تغيرت فيهما اللغة واتسعت مدلولاتها وبعدت غير قليل عن الفصحى المتمكنة

Spektrofluorimetrijsko određivanje ciklopiroks olamina prevođenjem u ternarni kompleks s Tb(III) i EDTA

A highly sensitive and selective spectrofluorimetric method was developed for the determination of ciclopirox olamine in raw material and in dosage forms. The proposed method is based on the formation of a ternary complex with Tb(III) in the presence of ethylenediaminetetraacetic acid. It was found that this complex manifests intense fluorescence at λem 489 and 545 nm with excitation at 295 nm. Different experimental parameters affecting the fluorescence intensity of the complex were carefully studied and incorporated into the procedure. Under the described conditions, the method is applicable over the concentration range of 30150 and 1070 ng mL-1 with minimum detectability of 6.7 and 0.9 ng mL-1 at λem 489 and 545 nm, respectively. The mean percentage recovery at λem 489 and λem 545 nm ranged between 98.7 and 100.2 for the pure substance, solution, and cream. Relative error of 0.10.4% and RSD up to 0.9% were estimated at λem 489 and 545 nm. A proposal of the reaction pathway is given.Razvijena je vrlo osjetljiva i selektivna spektrofluorimetrijska metoda za određivanje antimikotika ciklopiroks olamina, kao čiste supstancije i u ljekovitim oblicima. Metoda se temelji na stvaranju kompleksa s Tb(III) u prisutnosti etilendiamintetraoctene kiseline. Nakon ekscitacije pri 295 nm taj kompleks intenzivno fluorescira pri λem 489 i 545 nm. Proučavani su različiti eksperimentalni parametri koji utječu na intenzitet fluorescencije kompleksa. Za opisane uvjete metoda se može primijeniti u koncentracijskom području 30150 i 10 70 ng mL-1. Minimalna koncentracija koja se može odrediti je 6,7, odnosno 0,9 ng mL-1 na λem 489, odnosno 545 nm. Analitički povrat pri λem 489 i λem 545 nm iznosio je 98,7100,2% za čistu supstanciju, otopinu i kremu. Relativna pogreška metode je 0,10,4%, a relativna standardna devijacija 0,9%. Predložena je jednažba kemijske reakcije

Chemical Composition and In Vitro Digestibility of Pleurotus ostreatus Spent Rice Straw

The nutritive value of rice straw (RS) and Pleurotus ostreatus spent rice straw (SRS) was studied by analyzing its proximate composition, fiber fractions, in vitro digestibility, amino acids content and scanning electron microscopy (SEM). The possibility of replacing berseem clover (BC; Trifolium alexandrinum) with SRS at different levels also was studied. Results showed higher protein content for SRS compared to RS (3.4 to 11.7%) while, DM, OM, NFE, CF, NDF, ADF, ADL, hemicellulose and cellulose were less for SRS than for RS. Highest concentration of amino acids (mg/100 g) was in SRS compared to RS. The SEM showed an extensive damage of SRS when compared to RS. Data also showed that SRS had higher in vitro dry matter disappearance (DMD) and in vitro organic matter disappearance (OMD) compared to RS. Results of in vitro study also, indicated that the levels of 50 and 90% replacement had the highest values of DMD and OMD compared to the other levels. It could be concluded from this study that treatment of RS with Pleurotus ostreatus improved the potential feeding value of the resultant substrates (i.e. SRS) as feed resources for ruminants and possibility of replacing BC with SRS at high levels of up to 50 or 90% from diets

Facile synthesis of new fused and non-fused heterocyclic systems from a γ-ketoacid

The chemical reactivity of 4-(2-tetryl)-4-oxobut-2-enoic acid towards carbon, nitrogen, oxygen, sulfur nucleophiles and binucleophiles namely o-phenylenediamine, o-aminophenol, and o-aminothiophenol has been studied. The investigated nucleophilic reactions result in the formation of heterocyclic compounds with fused and non-fused systems namely, pyridazinone, tetrhydroquinoline, quinoxalone, oxazinone, thiazole and benzocoumarin

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London