Semantic Clustering of Search Engine Results

This paper presents a novel approach for search engine results clustering that relies on the semantics of the retrieved documents rather than the terms in those documents. The proposed approach takes into consideration both lexical and semantics similarities among documents and applies activation spreading technique in order to generate semantically meaningful clusters. This approach allows documents that are semantically similar to be clustered together rather than clustering documents based on similar terms. A prototype is implemented and several experiments are conducted to test the prospered solution. The result of the experiment confirmed that the proposed solution achieves remarkable results in terms of precision

Carpal tunnel syndrome in patients with and without diabetes mellitus in Upper Egypt: The impact of electrophysiological and ultrasonographical studies

Background: Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy in the upper extremity. Nerve conduction studies (NCS) is the most valid way of diagnosing CTS in combination of these clinical symptoms together with positive signs by physical examination. Ultrasonography is a useful non-invasive diagnostic method for CTS and there is considerable correlation between the electrophysiological tests and the measurements of cross-sectional area (CSA) by ultrasonography. Many studies have shown that the carpal tunnel syndrome seems to occur more frequently in patients with diabetes mellitus and might be associated with the duration of diabetes mellitus, microvascular complications and degree of glycemic control. Although diabetes mellitus is a risk factor for CTS, reports about median nerve CSA measurements between CTS patients with and without DM are scant. This prospective study aimed to evaluate whether or not ultrasonographic findings of the median nerve is different between DM and non-DM-CTS patients. To correlate the diagnostic results in both DM and non-DMCTS patients.Patients and methods: Thirty six non-diabetic patients and twenty five diabetic patients with CTS were assessed. All patients were subjected to thorough history taking, full clinical examination, electrophysiological assessment of wrists and gray scale ultrasonography (US).Results: High mean cross sectional area of median nerve (CSA) on ultrasonographical studies was detected with non-significant difference between both groups. Additionally, a non-significant difference for flattening ratio was found between two groups. Moreover, there was a highly significant positive correlation between electro diagnostic and ultrasonographic results in diabetic patients.Conclusion: The CSA of median nerve is larger in CTS hands in both DM and non-DM patients. Mean electro-diagnostic parameters were not significant predictors of CTS in patients with diabetes. The combination of electrophysiological and ultrasonography provides diagnostic effective tools across the entire spectrum of CTS in diabetic and non-diabetic patients. Nevertheless, screening for DM in patients with CTS is not recommended.Keywords: Carpal tunnel syndrome (CTS), Diabetes mellitus (DM), Diabetic polyneuropathy (DPN), Electrophysiological and ultrasonography (US

NUMERICAL INVESTIGATION OF LAMINAR MIXED CONVECTION IN TROMBE WALL CHANNEL

The two dimensional steady, combined forced and natural convection in vertical channel is investigated for laminar regime. To simulate the Trombe wall channel geometry properly, horizontal inlet and exit segments have been added to the vertical channel. The vertical walls of the channel are maintained at constant but different temperature while horizontal walls are insulated. A finite difference method using up-wind differencing for the nonlinear convective terms, and central differencing for the second order derivatives, is employed to solve the governing differential equations for the mass, momentum, and energy balances. The solution is obtained for stream function, vorticity and temperature as dependent variables by iterative technique known as successive substitution with overrelaxation. The flow and temperature patterns in the channel are obtained for Reynolds numbers and Grashof number ranging from 25 to 100 and (100 to 1,000,00,) respectively. A computer program ( Fortran 90 ) is built to calculate the fraction factor and the total average Nusselt number (Nu) also the average heat transfer Q in steady state and for Aspect ratio Ar (10) and Grashof number GR (10 2 − 10 5 ), the fluid Prandtl number is fixed at (Pr=0.733) and Reynolds number Re (25-100). The results show reasonable representation to the relation between Nusselt number and friction factor with other parameters (Ar, GR and Re). Nu is increased with increasing Re and GR but it decreases with Ar increase and (Q) is increased with increasing Re ,GR and Ar. At the same time, the product friction factor(fRe) increased with (GR) and (Ar)increased and (Re )decrease. Comparison of the result with the previous work shows a good agreemen

Hydrogeology and Water Quality of Umm Alradhma Aquifer, Eastern Saudi Arabia

Umm Alradhma limestone aquifer represents the most important aquifers in Saudi Arabia. This aquifer is the largest groundwater reservoir in the Arabian Peninsula. It has high potential of groundwater with average saturated thickness of Umm Alradhma 270 m. the average transmissivity, hydraulic conductivity and effective porosity of Umm Alradhma limestone aquifer are 5800 m2/day, 33 m3/day and 30% respectively. The groundwater of the Umm Alradhma limestone aquifer exists under confined condition in the study area. The productivity of the wells reached 704000 m3/day and provided Riyadh City about 300,000 m3/day. The hydrochemical analyses of 52 groundwater samples representing Umm Alradhma limestone aquifer reveal that the groundwater origin is meteoric. The presence of marine salts in groundwater is attributed to the effective leaching and dissolution processes through the flow path within the aquifer materials (limestone, dolomitic limestone and dolomite). The groundwater salinity of the Umm Alradhma limestone aquifer in the study area ranges between 1195-1429 ppm. This suggests that groundwater of Umm Alradhma limestone aquifer is acceptable for domestic, industrial and agricultural purposes. Keywords: Umm Alradhma aquifer, Hydrogeology, Water Qualit

Environmental Impact of Landfill on Groundwater, South East of Riyadh, Saudi Arabia

The main objective of this work had been given to the environmental impact of landfill on groundwater. The groundwater in the study area had problems caused by the landfill and the high volumes of sewage water percolating into the groundwater. The existing soil stratigraphy at the landfill consisting of sandy sheet and fractured limestone lead to increasing leachate percolation into the groundwater. The groundwater resources are used mainly for crop irrigation in an agriculture dominated area. The chemical analysis of groundwater indicates that nitrate pollution can be a serious problem affecting groundwater due to the infiltration of leachate in landfill downward to groundwater and the use of nitrogen (N) fertilizers in agriculture. The high concentrations of NO3- and Zn especially in landfill site in groundwater, likely indicate that groundwater is being significantly affected by leachate percolation. The nitrate and Zinc concentrations in groundwater samples in landfill site reach 191 ppm and 1473 ? g/L respectively. The groundwater in the study area is exploited from fractured limestone aquifer belonging to several limestone formations and groundwater of the concerned aquifer exists under unconfined conditions. The groundwater flow direction is from the northwest to the southeast direction. The leachate produced by waste disposal sites contains large amounts of substances which are likely to contaminate groundwater. Chemical analyses were carried out on groundwater samples collected from the neighborhood of landfill yard and spread to southeast direction. The effects of dumping activity on groundwater appeared most clearly as high concentrations of total dissolved solids (TDS), electrical conductivity (EC), total hardness (TH), chloride, nitrates and sulphates. Groundwater samples from the wells situated close to the landfill were found to be more contaminated than that of the wells situated farther away. Keywords: Environmental Impact, Landfill, Groundwater, Saudi Arabi

Synthesis and Photocatalytic Activity of Single Crystal Titanate: Part-1

Single crystal TiO2 nanotubes (TNTs) were prepared using modified hydrothermal method by treatment of prepared TiO2 with NaOH aqueous solution and characterized by the X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), thermogravimetric (TG) analysis, BET surface area analysis, Raman spectroscopy, FTIR and UV–vis/DR spectroscopy. Detailed study for the effect of calcinations temperature on the morphology, textural properties, adsorption amount and photocatalytic activity of TiO2 nanotubes was performed. The results showed that the calcinations temperature remarkably altered the phase composition. HRTEM showed that the high-purity nanotubes can be produced through the hydrothermal treatment of TiO2, calcinated at 250 ?C.  It was found that the obtained high-purity TNTs have outer diameter of the tubular structures around 15 nm and the length is around 70 nm, the wall of nanotube is 2 layers in one side whereas it is 3 layers in another side and the interlayer spacing is about 1–1.5 nm. The prepared TiO2 nanotubes show enhanced catalytic activity in photocatalytic phenol degradation compared with TiO2 nanoparticles which show lower catalytic activities. Keywords: Titanate, Single Crystal, hydrothermal metho

Participation of MCP-induced protein 1 in lipopolysaccharide preconditioning-induced ischemic stroke tolerance by regulating the expression of proinflammatory cytokines

Background: Lipopolysaccharide (LPS) preconditioning-induced neuroprotection is known to be related to suppression of the inflammatory response in the ischemic area. This study seeks to determine if monocyte chemotactic protein-induced protein 1 (MCPIP1), a recently identified CCCH Zn finger-containing protein, plays a role in focal brain ischemia and to elucidate the mechanisms of LPS-induced ischemic brain tolerance. Methods: Transcription and expression of MCPIP1 gene was monitored by qRT-PCR and Western blot. Mouse microglia was prepared from cortices of C57BL/6 mouse brain and primary human microglia was acquired from Clonexpress, Inc. Wild type and MCPIP1 knockout mice were treated with LPS (0.2 mg/kg) 24 hours before brain ischemia induced by transient middle cerebral artery occlusion (MCAO). The infarct was measured by 2,3,5-triphenyltetrazolium chloride (TTC) staining. Results: MCPIP1 protein and mRNA levels significantly increased in both mouse and human microglia and mouse brain undergoing LPS preconditioning. MCPIP1 mRNA level significantly increased in mice ipsilateral brain than that of contralateral side after MCAO. The mortality of MCPIP1 knockout mice was significantly higher than that of wildtype after MCAO. MCPIP1 deficiency caused significant increase in the infarct volume compared with wild type mice undergoing LPS preconditioning. MCPIP1 deficiency caused significant upregulation of proinflammatory cytokines in mouse brain. Furthermore, MCPIP1 deficiency increased c-Jun N terminal kinase (JNK) activation substantially. Inhibition of JNK signaling decreased the production of proinflammatory cytokines in MCPIP1 knock out mice after MCAO. Conclusions: Our data indicate that absence of MCPIP1 exacerbates ischemic brain damage by upregulation of proinflammatory cytokines and that MCPIP1 participates in LPS-induced ischemic stroke tolerance

Risk factors for developing congenital nasolacrimal duct obstruction

AbstractObjectiveTo identify potential risk factors for developing congenital nasolacrimal duct obstruction (CNLDO).Study design and methodsA cross-sectional study. A quantitative questionnaire was distributed to a sample of mothers attending the Pediatrics Clinic at King Khalid University Hospital, Riyadh, Saudi Arabia.ResultsA total of 756 mothers responded to our questionnaire. Of the 756 filled questionnaires, 389 (51.67%) were male children. 5.3% of the mothers lived in non-urban settings. CNLDO was reported in the children attending the clinic by 17.1% (129/756) of their mothers. Average age (±SD) of infants when persistent tearing was noticed was 3.2±2.7months, while average age (±SD) of resolution was 9.6±3.7months. Of the children with CNLDO, 37.2% (48/129) still have persistent tearing at the time of distributing the questionnaire. Among the group with CNLDO, 17% (22/129) of their mothers have experienced an infection during pregnancy (p=0.022). Within the same group, 14.7% (19/129) of the affected children were reported by their mothers to have other children with CNLDO which was statistically significant (p=<0.001).ConclusionCNLDO could have a genetic predisposition and maternal infection is a possible risk factor for developing CNLDO. Surgical management awareness should be emphasized to relieve children from this relatively common and benign condition

Probability and Sampling in Dentistry

Probability and sampling in dentistry are two fundamentals which have great importance in clinical research. Many research works in dentistry shows lack of proper understanding and use of these two factors. The definition of probability is incredibly significant in daily life. Statistical analysis is based on this particularly useful definition. In fact, the function of probability in modern science is that of substituting for certainty. Probabilities are numbers that represent the probability that a specific occurrence will occur. We learn about the odds of many daily cases, ranging from weather predictions (probability of rain or snow) to lotteries (probability of winning a major jackpot). In biostatistical applications, probability theory underlies the statistical inference. Statistical inference means drawing generalizations or inferences on unknown population parameters. After selecting a sample from the population of interest, we calculate the characteristics under analysis, summarize the characteristics in our sample, and then draw inferences about the population based on what we find in the sample. Population and sampling are two critical aspects of study design. The population is a group of individuals who share common relations. A sample is a population subset. The size of the sample is the number of individuals in the sample. The more representative the sample of the population, the surer the researcher can be about the validity of the data. In this module, we will explore sampling methods, basic principles of probability, and applications of probability theory. The definition of probability is introduced, and the function of probability distributions is discussed in the statistical theory, with reference to the normal distribution and its characteristics. Sampling and sampling variations are defined, along with the sampling error, the standard error of the mean and the confidence intervals for determining the likely magnitude of the population mean. Medical study typically includes patients with an illness or disorder. The generalization of clinical research results is focused on several factors linked to the internal and external validity of the research methods. The sampling process is the key methodological problem that affects the generalizability of clinical research results. In this educational article, we also clarify the various methods of sampling in clinical research