36 research outputs found
Investigation of Changing Pore Topology and Porosity during Matrix Acidizing using Different Chelating Agents
Core flooding acidizing experiments on sandstone/carbonate formation are usually performed in the laboratory to observe different physical phenomena and to design acidizing stimulation jobs for the field. During the tests, some key parameters are analyzed such as pore volume required for breakthrough as well as pressure. Hydrochloric acid (HCl) is commonly used in the carbonate matrix acidizing while Mud acid (HF: HCl) is usually applied during the sandstone acidizing to remove damage around the well bore. However, many problems are associated with the application of these acids, such as fast reaction, corrosion and incompatibility of HCl with some minerals (illite). To overcome these problems, chelating agents (HEDTA, EDTA and GLDA) were used in this research. Colton tight sandstone and Guelph Dolomite core samples were used in this study. The experiments usually are defined in terms of porosity, permeability, dissolution and pore topology. Effluent samples were analyzed to determine dissolved iron, sodium, potassium, calcium and other positive ions using Inductively Coupled Plasma (ICP). Meanwhile Nuclear Magnetic Resonance (NMR) was employed to determine porosity and pore structure of the core sample. Core flood experiments on Berea sandstone cores and dolomite samples with dimensions of 1.5 in × 3 in were conducted at a flow rate of 1 cc/min under 150oF temperature. NMR and porosity analysis concluded that applied chemicals are effective in creating fresh pore spaces. ICP analysis concluded that HEDTA showed good ability to chelate calcium, sodium, magnesium, potassium and iron. It can be established from the analysis that HEDTA can increase more amount of permeability as compared to other chelates
Association between Birth Defects and Cancer Risk among Children and Adolescents in a Population-Based Assessment of 10 Million Live Births
Importance: Birth defects affect approximately 1 in 33 children. Some birth defects are known to be strongly associated with childhood cancer (eg, trisomy 21 and acute leukemia). However, comprehensive evaluations of childhood cancer risk in those with birth defects have been limited in previous studies by insufficient sample sizes. Objectives: To identify specific birth defect-childhood cancer (BD-CC) associations and characterize cancer risk in children by increasing number of nonchromosomal birth defects. Design, Setting, and Participants: This multistate, population-based registry linkage study pooled statewide data on births, birth defects, and cancer from Texas, Arkansas, Michigan, and North Carolina on 10181074 children born from January 1, 1992, to December 31, 2013. Children were followed up to 18 years of age for a diagnosis of cancer. Data were retrieved between September 26, 2016, and September 21, 2017, and data analysis was performed from September 2, 2017, to March 21, 2019. Exposures: Birth defects diagnoses (chromosomal anomalies and nonchromosomal birth defects) recorded by statewide, population-based birth defects registries. Main Outcomes and Measures: Cancer diagnosis before age 18 years, as recorded in state cancer registries. Cox regression models were used to generate hazard ratios (HRs) and 95% CIs to evaluate BD-CC associations and the association between number of nonchromosomal defects and cancer risk. Results: Compared with children without any birth defects, children with chromosomal anomalies were 11.6 (95% CI, 10.4-12.9) times more likely to be diagnosed with cancer, whereas children with nonchromosomal birth defects were 2.5 (95% CI, 2.4-2.6) times more likely to be diagnosed with cancer before 18 years of age. An increasing number of nonchromosomal birth defects was associated with a corresponding increase in the risk of cancer. Children with 4 or more major birth defects were 5.9 (95% CI, 5.3-6.4) times more likely to be diagnosed with cancer compared with those without a birth defect. In the analysis of 72 specific BD-CC patterns, 40 HRs were statistically significant (adjusted P <.05) after accounting for multiple comparisons. Cancers most frequently associated with nonchromosomal defects were hepatoblastoma and neuroblastoma. Conclusions and Relevance: Several significant and novel associations were observed between specific birth defects and cancers. Among children with nonchromosomal birth defects, the number of major birth defects diagnosed was significantly and directly associated with cancer risk. These findings could inform clinical treatment for children with birth defects and may elucidate mechanisms that lead to these complex outcomes
Tissue transglutaminase and its relationship to cell cycle kinetics, apoptosis and tumour progression
SIGLEAvailable from British Library Document Supply Centre-DSC:DXN012243 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Development of a dewaxing protocol for tissue-engineered models of the oral mucosa used for Raman spectroscopic analysis
We demonstrate that wax-embedded models of tissue-engineered oral mucosa can be effectively dewaxed using xylene for Raman spectroscopic analysis. Tissue sections of 20 m thickness were cut and mounted onto glass slides. Sections were placed in xylene for increasing lengths from 2 to 45 min. Acquired Raman spectra revealed the wax contribution in the fingerprint region until 28-min treatment in xylene. Good quality and wax-free spectra were recorded at 30, 35, 40, and 45 min in xylene with no significant differences among them. It is essential to collect uncontaminated Raman spectra in order to achieve authentic results because the fingerprint region of biological tissues holds extremely vital information that is of diagnostic significance in cancer. © 2014 Taylor & Francis Group, LLC
An update on glass fiber dental restorative composites: A systematic review
Dentistry is a much developed field in the last few decades. New techniques have changed the conventional treatment methods as applications of new dental materials give better outcomes. The current century has suddenly forced on dentistry, a new paradigm regarding expected standards for state-of-the-art patient care. Within the field of restorative dentistry, the incredible advances in dental materials research have led to the current availability of esthetic adhesive restorations. The chemistry and structure of the resins and the nature of the glass fiber reinforced systems in dental composites are reviewed in relation to their influence and properties including mechanical, physical, thermal, biocompatibility, technique sensitivity, mode and rate of failure of restorations on clinical application. It is clear that a deeper understanding of the structure of the polymeric matrix and resin-based dental composite is required. As a result of ongoing research in the area of glass fiber reinforced composites and with the development and advancement of these composites, the future prospects of resin-based composite are encouraging. © 2014 Elsevier B.V. All rights reserved
Evaluating the impact of osmopriming varying with polyethylene glycol concentrations and durations on soybean
The objective of this study was to determine the effects of osmo and hydro-priming on phenology, yield components and biomass yield of soybean (Glycine max) cv. William-82. After a laboratory experiment to determine the optimum combination of priming duration and polyethylene glycol 8000 (PEG 8000) concentration, field experiment was conducted in 2003 and 2004 with three priming durations (6, 12 and 18 h) and five different concentrations of PEG 8000 solution (0, -0.2, -0.5, -1.1, -1.8 , -3.0 and -4.2 MPa), together with a dry seed (non primed) control. Primed and non-primed seeds were sown in the field. During both years, plants from primed seed flowered and matured faster than plants from non-primed seed. Primed seed gave taller plants. Averaged over all treatments, priming for 6 h or with -1.1 MPa, were the most beneficial treatments. It is concluded that priming with PEG was much effective but priming with water alone was also better than control
Oral health-related knowledge and assessment of oral health status of diabetic patients attending dental clinics at college of dentistry, Hail, Saudi Arabia
Aim: This study was aimed to evaluate the oral health status and knowledge of diabetic and nondiabetic patients attending College of Dentistry clinics, Hail, the Kingdom of Saudi Arabia. Materials and methods: It was an observational cross-sectional study. Using nonprobability convenient sampling technique, data were collected from 202 respondents. A total of 202 diabetic and nondiabetic patients were screened for the study. Data were collected by interview using the structured, self-administered questionnaire, and assessment of oral health status was done by clinical examination. The collected data were analyzed using IBM SPSS software. The data were displayed as numbers and percentages and association among the variable of interests was measured using Pearson Chi-square. Results: Of the 202 patients, 102 (50.6%) were males and 100 (49.4%) were females. Majority of the patients, 71 (35.2%) were in the age-group of 30-40 years. In all, 128 (63.4%) participants knew the effect of diabetes mellitus (DM) on oral health, 167 (82.7%) knew that diabetic patients needed special healthcare, 152 (75.25%) had never spoken to their doctors about oral health, and 164 (81.19%) had never spoken to their dentists regarding diabetes. Conclusion: The complications associated with oral health are more common in diabetic patients when compared to the nondiabetic patients. This is the case in both male and female patients visiting the College of Dentistry in the Hail region. Clinical significance: Diabetes mellitus is associated with increased susceptibility to oral infections especially periodontal disease. Role of a general dentist in diagnosis and raising patient awareness toward DM and its effects on oral health need to be emphasized