THE GRAIN COARSENING AND SUBSEQUENT TRANSFORMATION OF AUSTENITE IN THE HSLA STEEL DURING HIGH TEMPERATURE THERMOMECHANICAL PROCESSING

In heavy steel sections, fundamental properties such as strength and toughness are improved remarkably by refining and homogenizing the final ferrite microstructure. Conventionally, the microstructural refinement of the final ferrite depends mainly on the austenite grain size, morphology and composition prior to the phase transformation as well as the cooling rate during the transformation. The production of heavy sections by universal-type rolling mills takes place at elevated temperature (above 1200 ºC) followed by low cooling rates (<0.1 ºC/sec). These processing conditions produce coarse austenite grains and subsequently coarse ferrite grains in addition to other undesirable low temperature transformation products. In heavy steel sections, therefore, the refinement of the ferrite microstructure through modern TMP techniques is not feasible. The main objective of this study is to investigate the feasibility of refining the ferrite microstructure and eliminate the high-carbon low transformation products in heavy steel sections using the particle-stimulated nucleation, PSN, mechanism to enhance the nucleation of the intragranular ferrite, IGF.In this investigation, the MnS and Ti-oxide inclusions were used to promote the intragranular ferrite (IGF) nucleation mechanism in a typical ASTM A572 grade 50 Steel. This work included the study of the decomposition behavior of coarse grained austenite and nucleation of the IGF as a function of very slow cooling rate. In addition, the effects of the inclusions type, size and volume fraction on the kinetics (nucleation and growth) of IGF were investigated. The main findings of this research were that the refining of ferrite microstructure is achieved, successfully, through enhancing the IGF nucleation with implementing of the PSN mechanism. Additionally, the efficiency of the inclusion as an IGF nucleation site is mainly related to the inclusion size and type

Analisis Penentuan Sektor Unggulan Perekonomian di Kabupaten Kubu Raya

This research intends to determine leading sectors in the Regency Kubu Raya. Leading sectorscan be determined by combining some analysis tools, such as: Typology Klassen, combinedLocation Quotient dan Dynamic Location Quotient,  Shift Share. Time series data is used in thisresearch, such as PDRB of Kubu Raya Regency and West Borneo Province from 2008 to 2013based on constant basic price. The result of this research showed that  leading sectors economy inKubu Raya Regency based on combined analysing from three analysis tools are transport andcommunications sector. Potential sector to be developed to become  leading sectors in the futureare processing industry, elictricity, gas, and clean water sector. Meanwhile, from the fiveagriculture sub sectors in Kubu Raya Regency based on combined analysis from the threeanalysis tools showed that livestock sub sector has potential to be developed to become a leadingsector economy in Kubu Raya Regency

Newborn Screening Services in Bahrain between 1985 and 2010

Introduction. The incidence of genetic blood disease in Bahrain has declined gradually since 1984 when the Ministry of Health (MOH) instituted a prevention campaign. The national NBS program for hemoglobinopathies was started in May 2007, financed by the national budget. Setting. Genetics department, Salmaniya Medical Complex, MOH, Bahrain. Methodology. The genetics, nursing, pathology, and pediatric departments were involved in the study. This service was offered to all infants. Cord blood samples were collected at birth and were then sent to the laboratory. Results. During 3.5 years after the program was implemented, we screened 38,940 newborns (NBs), of which 17,375 were screened in 2008, 10,248 in 2009, and 11,317 in 2010. The number of affected NBs was 128 in both 2007 and 2008, 58 in 2009, and 47 in 2010, as the average number of affected NBs in 2010 was 4 per month. The incidence of affected NBs was found to be 0.7% in 2008, 0.6% in 2009, and 0.4% in 2010. Conclusion. NBS is an essential step for the early diagnosis and treatment of affected NBs, future recurrence of the disease in the same family. In Bahrain, the number of affected NBs has declined by 75% during the last 20

The effect of hyoscine butylbromide in shortening the first stage of labor: A double blind, randomized, controlled, clinical trial

Nourah H Al Qahtani1 Fatma Al Hajeri21MRCOG, College of Medicine, Department of Obstetrics and Gynecology in King Fahad University Hospital, University of Dammam, Saudi Arabia; 2Department of Obstetrics and Gynecology in King Fahad University Hospital, Saudi ArabiaBackground and objectives: Hyoscine butylbromide (HBB) is widely used in labor rooms. There have been many studies on the use of HBB during labor with conflicting results, involving both primiparous and multiparous women. The aim of this trial was to study the efficacy of HBB for shortening the first stage of labor in primiparous women.Methods: The study was a randomized, double blind, controlled trial. Ninety-seven primigravid term pregnant women in spontaneous labor received either hyoscine butylbromide or a placebo intramuscularly once the women entered the active phase of labor. The primary outcome measured was the duration of the first stage of labor. Secondary outcomes were the duration of the second and third stages of labor, blood loss at delivery, rate of cesarean section, and Apgar scores for the neonates.Results: A total of 97 women yielded data for analysis. Of these, 45 women received the placebo and 52 received HBB. The mean duration of the first stage in the control group was 215 minutes, compared with 165 minutes in the study group, representing a decrease of 23.3% (P = 0.001). There were no significant changes in the duration of the second (P = 0.063) or third (P = 0.0418) stages of labor, and no significant differences in blood loss or Apgar scores. There was a slightly higher (but statistically insignificant) rate of instrumental delivery in the control group, but no difference in the Cesarean section rate. There was a 60% reduction in opioid analgesic use in the HBB group.Conclusion: HBB is effective in significantly reducing the duration of the first stage of labor, and is not associated with any apparent adverse maternal or neonatal outcomes.Keywords: hyoscine butylbromide, first stage, labor, duration, augmentatio

Characterization of sub-nuclear changes in Caenorhabditis elegans embryos exposed to brief, intermediate and long-term anoxia to analyze anoxia-induced cell cycle arrest

BACKGROUND: The soil nematode C. elegans survives oxygen-deprived conditions (anoxia; <.001 kPa O(2)) by entering into a state of suspended animation in which cell cycle progression reversibly arrests. The majority of blastomeres of embryos exposed to anoxia arrest at interphase, prophase and metaphase. The spindle checkpoint proteins SAN-1 and MDF-2 are required for embryos to survive 24 hours of anoxia. To further investigate the mechanism of cell-cycle arrest we examined and compared sub-nuclear changes such as chromatin localization pattern, post-translational modification of histone H3, spindle microtubules, and localization of the spindle checkpoint protein SAN-1 with respect to various anoxia exposure time points. To ensure analysis of embryos exposed to anoxia and not post-anoxic recovery we fixed all embryos in an anoxia glove box chamber. RESULTS: Embryos exposed to brief periods to anoxia (30 minutes) contain prophase blastomeres with chromosomes in close proximity to the nuclear membrane, condensation of interphase chromatin and metaphase blastomeres with reduced spindle microtubules density. Embryos exposed to longer periods of anoxia (1–3 days) display several characteristics including interphase chromatin that is further condensed and in close proximity to the nuclear membrane, reduction in spindle structure perimeter and reduced localization of SAN-1 at the kinetochore. Additionally, we show that the spindle checkpoint protein SAN-1 is required for brief periods of anoxia-induced cell cycle arrest, thus demonstrating that this gene product is vital for early anoxia responses. In this report we suggest that the events that occur as an immediate response to brief periods of anoxia directs cell cycle arrest. CONCLUSION: From our results we conclude that the sub-nuclear characteristics of embryos exposed to anoxia depends upon exposure time as assayed using brief (30 minutes), intermediate (6 or 12 hours) or long-term (24 or 72 hours) exposures. Analyzing these changes will lead to an understanding of the mechanisms required for initiation and maintenance of cell cycle arrest in respect to anoxia exposure time as well as order the events that occur to bring about anoxia-induced cell cycle arrest

Genetic and Cellular Analysis of Anoxia-Induced Cell Cycle Arrest in Caenorhabditis elegans

The soil-nematode Caenorhabditis elegans survives oxygen deprivation (anoxia < 0.001 kPa of O2, 0% O2) by entering into a state of suspended animation during which cell cycle progression at interphase, prophase and metaphase stage of mitosis is arrested. I conducted cell biological characterization of embryos exposed to various anoxia exposure times, to demonstrate the requirement and functional role of spindle checkpoint gene san-1 during brief anoxia exposure. I conducted a synthetic lethal screen, which has identified genetic interactions between san-1, other spindle checkpoint genes, and the kinetochore gene hcp-1. Furthermore, I investigated the genetic and cellular mechanisms involved in anoxia-induced prophase arrest, a hallmark of which includes chromosomes docked at the nuclear membrane. First, I conducted in vivo analysis of embryos carried inside the uterus of an adult and exposed to anoxic conditions. These studies demonstrated that anoxia exposure prevents nuclear envelope breakdown (NEBD) in prophase blastomeres. Second, I exposed C. elegans embryos to other conditions of mitotic stress such as microtubule depolymerizing agent nocodazole and mitochondrial inhibitor sodium azide. Results demonstrate that NEBD and chromosome docking are independent of microtubule function. Additionally, unlike anoxia, exposure to sodium azide causes chromosome docking in prophase blastomeres but severely affects embryonic viability. Finally, to identify the genetic mechanism(s) of anoxia-induced prophase arrest, I conducted extensive RNA interference (RNAi) screen of a subset of kinetochore and inner nuclear membrane genes. RNAi analysis has identified the novel role of 2 nucleoporins in anoxia-induced prophase arrest

Analytical and numerical assessment of the effect of highly conductive inclusions distribution on the thermal conductivity of particulate composites

Highly conductive composites have found applications in thermal management, and the effective thermal conductivity plays a vital role in understanding the thermo-mechanical behavior of advanced composites. Experimental studies show that when highly conductive inclusions embedded in a polymeric matrix the particle forms conductive chain that drastically increase the effective thermal conductivity of two-phase particulate composites. In this study, we introduce a random network three dimensional (3D) percolation model which closely represent the experimentally observed scenario of the formation of the conductive chain by spherical particles. The prediction of the effective thermal conductivity obtained from percolation models is compared with the conventional micromechanical models of particulate composites having the cubical arrangement, the hexagonal arrangement and the random distribution of the spheres. In addition to that, the capabilities of predicting the effective thermal conductivity of a composite by different analytical models, micromechanical models, and, numerical models are also discussed and compared with the experimental data available in the literature. The results showed that random network percolation models give reasonable estimates of the effective thermal conductivity of the highly conductive particulate composites only in some cases. It is found that the developed percolation models perfectly represent the case of conduction through a composite containing randomly suspended interacting spheres and yield effective thermal conductivity results close to Jeffery's model. It is concluded that a more refined random network percolation model with the directional conductive chain of spheres should be developed to predict the effective thermal conductivity of advanced composites containing highly conductive inclusions