Imaging spontaneous imbibition in full Darcy‐scale samples at pore‐scale resolution by fast X‐ray tomography

Spontaneous imbibition is a process occurring in a porous medium which describes wetting phase replacing nonwetting phase spontaneously due to capillary forces. This process is conventionally investigated by standardized, well-established spontaneous imbibition tests. In these tests, for instance, a rock sample is surrounded by wetting fluid. The following cumulative production of nonwetting phase versus time is used as a qualitative measure for wettability. However, these test results are difficult to interpret, because many rocks do not show a homogeneous but a mixed wettability in which the wetting preference of a rock varies from location to location. Moreover, during the test the flow regime typically changes from countercurrent to cocurrent flow and no phase pressure or pressure drop can be recorded. To help interpretation, we complement Darcy-scale production curves with X-ray imaging to describe the differences in imbibition processes between water-wet and mixed-wet systems. We found that the formation of a spontaneous imbibition front occurs only for water-wet systems; mixed-wet systems show localized imbibition events only. The asymmetry of the front depends on the occurrence of preferred production sites, which influences interpretation. Fluid layers on the outside of mixed-wet samples increase connectivity of the drained phase and the effect of buoyancy on spontaneous imbibition. The wider implication of our study is the demonstration of the capability of benchtop laboratory equipment to image a full Darcy-scale experiment while at the same time obtaining pore-scale information, resolving the natural length and time scale of the underlying processes

CORRELATION OF ALKALOID CONTENT AND TASTE OF HONEY FROM VARIOUS PROVINCES IN INDONESIA

Objective: This study analyzed the correlation between alkaloid contents and taste (bitter and rough taste). Methods: Qualitative analysis was analyzed using Mayer and Draggendorff methods, while quantitative analysis was analyzed using spectrophotometric methods. Taste evaluation in each sample was carried out by descriptive method with parameters including bitter and rough taste. The correlation between alkaloid content and taste in honey was statistically analyzed using a correlation test. Results: The alkaloids testing showed that the sample with the highest alkaloid content was Tetragonula fuscobalteata honey from Sumbawa province, with an alkaloid content of 119.71 mg/g. In contrast, the sample with the lowest alkaloid content was Geniotrigona thoracica from West Sumatra at 21.24 mg/g. Taste evaluation results showed that the sample with the highest alkaloid content had the most bitter and rough taste. Conclusion: Honey that has the highest alkaloid content is T. fuscobalteata Sumbawa, with an alkaloid content of 119.71 mg/g, because the availability of adequate alkaloid feed supports this species. In contrast, the honey with the lowest alkaloid content was G. thorasica, with an alkaloid content of 21.24 mg/g, because the availability of adequate alkaloid feed did not support this species. Based on the data, the alkaloid content of honey has a linear correlation with the bitter and rough taste. The higher alkaloid content in honey causes the honey taste to become more bitter and rough

Development and validation of iranian children's participation assessment scale

Background: Participation is mostly cultural and familial based, and there is not any assessment scales for evaluating kids' participation in Iranian context, therefore the purpose of this study was developing children's participation assessment scale for Iranian children. Methods: Development of this scale occurred in two phases; phase I: planning: following reviewing the literature and adopting and compiling some items of available evaluation tools in the area (such as CAPE, CPQ, CLASS, Life-H) and receiving advice from two expert panels, the preliminary94- item questionnaire was prepared. Phase II: construct: the survey study was carried out on40 children and 21 of their parents to assess the popularity of the activity in Iran; thus, the items of the questionnaire reduced to 92 and after face and content validity, the final version prepared with 71 items. Results: The final 71-item questionnaire was developed in two parent-report and child-report versions. The 71 items based on the literature and expert panels' advice were categorized in 8 areas of occupation according to Occupational Therapy Practice Framework (ADL, IADL, Play, leisure, social participation, education, work, and sleep/rest). Conclusion: Iranian children's participation assessment is a useful and culturally relevant tool to measure participation of Iranian children. It can be used in rigorous clinical and population-based research

Factors affecting quality of care in family planning clinics: A study from Iran

Background. Despite good contraceptive coverage rates, recent studies in Iran have shown an alarmingly high incidence of unplanned pregnancy. Objective. To determine factors affecting quality of family planning services, a cross-sectional study was performed from June to August 2006 on women visiting urban Primary Health Care clinics in a provincial capital in western Iran. The primary focus of the study was on provider-client interaction. Method. We used a slightly edited version of a UNICEF checklist and a convenient sampling method to assess quality of care in 396 visits to the family planning sections at 25 delivery points. Results. Poor performance was observed notably in Counselling and Choice of method sections. In logistic regression analysis, the following factors were found to be associated with higher quality of care: provider experience OR (odds ratio) = 1.9, CI0.95 (confidence interval) = 1.2-3.0, low provider education (OR = 6.7, CI0.95 = 4.0=10.8), smaller workload at the clinic (OR = 3.7, CI0.95 = 2.0-6.7), and 'new client' status (OR = 4.2, CI0.95 = 2.6-6.7). Conclusion. This study identified the issues of counselling and information exchange as the quality domains in serious need of improvement; these areas are expected to be the focus of future training programmes for care providers. Also, priority should be given to devising effective supervision mechanisms and on-the-job training of senior nursing and midwifery graduates to make them more competent in delivering basic family planning services. © The Author 2008. Published by Oxford University Press in association with the International Society for Quality in Health Care; all rights reserved

The development of mouse early embryos in vitro in fibroblasts and cumulus cells co-cultures supplemented with retinoic acid

This study was designed to examine the effects of retinoic acid adding to cumulus and/or fibroblast cells monolayer on the development of mouse early embryos. One-cell mouse embryos were obtained from NMRI mice after superovulation by an intraperitoneal injection of 5 IU equine chorionic gonadotrophin (eCG) followed 48 hrs later by 5 IU human chorionic gonadotrophin (hCG). Mouse embryonic fibroblasts (MEF) were obtained from mouse fetuses and cumulus cells (CC) were prepared from mouse cumulus-oocyte complexes (COCs). To produce monolayer of cumulus and fibroblast cells, 1.0 × 105 cells/ml were plated into culture dishes in 100 μl droplets. The collected mouse embryos were cultured randomly into six different conditions, being supplemented (experiment, Exp) or not (control, Con) with 0.28 μg/ml of retinol acetate methyl-β-cyclodextrin (RA) for 96 hrs at 37°C in 5% CO2 in air, including: (1) culture media only (Con 1); (2) culture media plus RA (Exp 1); (3) co-culture with CC (Con 2); (4) co-culture with CC plus RA (Exp 2); (5) co-culture with MEF (Con 3) and (6) co-culture with MEF plus RA (Exp 3). The culture medium was Alpha Modification of Minimum Essential Medium Eagle (α-MEM) + 10% fetal bovine serum (FBS) with 100 IU/ml penicillin and 100 μg/ml streptomycin. The proportions of embryos passing the two-cell block were significantly higher in the MEF (Con 3) group compared to the other treatment groups (P<0.05). The percentage of the two-cell passed embryos developing to the blastocyst stage was significantly higher in the co-culture groups than that of the culture medium alone (P<0.05). After 96 hrs in culture, the rate of blastocyst stage for both groups of CC co-culture treatment (Con 2 and Exp 2) was identical but, adding RA into the MEF co-culture (Exp 3) resulted significantly lower in vitro development than that of the Con 3 group (29.2% vs. 57.7%, P<0.05). These results suggest that supplementation of co-culture groups with RA could not affect the embryos passing the block and developing to the blastocyst stage, although the presence of RA into the culture medium alone may improve passing the critical two-cell stage. Also, in vitro addition of RA to cells without receptors for retinol during long term co-culture may result early embryonic growth retardation

Effects of electrical stimulation of dorsal raphe nucleus on neuronal response properties of barrel cortex layer IV neurons following long-term sensory deprivation

Abstract: Objective To evaluate the effect of electrical stimulation of dorsal raphe nucleus (DRN) on response properties of layer IV barrel cortex neurons following long-term sensory deprivation. Methods: Male Wistar rats were divided into sensory-deprived (SD) and control (unplucked) groups. In SD group, all vibrissae except the D2 vibrissa were plucked on postnatal day one, and kept plucked for a period of 60 d. After that, whisker regrowth was allowed for 8-10 d. The D2 principal whisker (PW) and the D1 adjacent whisker (AW) were either deflected singly or both deflected in a serial order that the AW was deflected 20 ms before PW deflection for assessing lateral inhibition, and neuronal responses were recorded from layer IV of the D2 barrel cortex. DRN was electrically stimulated at inter-stimulus intervals (ISIs) ranging from 0 to 800 ms before whisker deflection. Results: PW-evoked responses increased in the SD group with DRN electrical stimulation at ISIs of 50 ms and 100 ms, whereas AW-evoked responses increased at ISI of 800 ms in both groups. Whisker plucking before DRN stimulation could enhance the responsiveness of barrel cortex neurons to PW deflection and decrease the responsiveness to AW deflection. DRN electrical stimulation significantly reduced this difference only in PW-evoked responses between groups. Besides, no DRN stimulation-related changes in response latency were observed following PW or AW deflection in either group. Moreover, condition test (CT) ratio increased in SD rats, while DRN stimulation did not affect the CT ratio in either group. There was no obvious change in 5-HT2A receptor protein density in barrel cortex between SD and control groups. Conclusion: These results suggest that DRN electrical stimulation can modulate information processing in the SD barrel cortex

Effect of folic acid and zinc sulphate on endocrine parameters and seminal antioxidant level after varicocelectomy

Varicocele is among the most common problems which may lead to male infertility. Spermatogenesis is impaired as a consequence of this vascular defect, through mechanisms that are not well described. This study aimed to evaluate serum hormonal level (inhibin B, FSH and testosterone) and seminal plasma antioxidant defence levels after folic acid and zinc sulphate administration in varicocelectomised patients. Participants were randomly allocated to four experimental groups. Our randomisation schedule was as follows: zinc sulphate/ folic acid, folic acid, zinc sulphate and placebo. The patients underwent varicocelectomy, before which a blood and semen sample were obtained and also three and six months after varicocelectomy for evaluation of blood hormonal level (FSH, testosterone, inhibin B) and seminal oxidative stress status (nitric oxide, superoxide dismutase, total antioxidant capacity). Patients in different groups took orally one capsule per day after dinner following varicocelectomy for 6 months. A significant rise in peripheral blood inhibin B and seminal plasma activity was detected in the zinc sulphate/folic acid group after 6 months. The present clinical trial indicates a change in the hormonal status of varicocelectomised patients following long-term administration of zinc sulphate and folic acid

An investigation into the roles of chlorides and sulphate salts on the performance of low salinity injection in sandstone reservoirs : experimental approach

Numerous studies have been carried out to ascertain the mechanisms of low salinity and smart water flooding technique for improved oil recovery. Focus were often on brine composition and, specifically the cationic content in sandstone reservoirs. Given the importance of the salt composition and concentration, tweaking the active ions which are responsible for the fluids-rock equilibrium will bring into effect numerous mechanisms of displacement which have been extensively debated. This experimental study, however, was carried out to evaluate the extent of the roles of chloride and sulphate-based brines in improved oil recovery. To carry this out, 70,000 ppm sulphates and chloride-based brines were prepared to simulate formation water and 5,000ppm brines of the same species as low salinity displacement fluids. Core flooding process was used to simulate the displacement of oil by using four (4) native sandstones core samples, obtained from Burgan oil field in Kuwait, at operating conditions of 1500 psig and 50oC. The core samples were injected with 70,000 ppm chloride and sulphates and subsequently flooded with the 5,000 ppm counterparts in a forced imbibition process. Separate evaluations of chloride and sulphate-based brines were carried out to investigate the displacement efficiencies of each brine species. The results showed that the in both high and low salinity displacement tests, the SO4 brine presented better recovery of up to 89% of the initial oil saturation (Soi). Several mechanisms of displacement were observed to be responsible for improved recovery during SO4 brine displacement. IFT measurement experiments also confirmed that there was reduction in IFT at test conditions between SO4 brine and oil and visual inspection of the effluent showed a degree emulsification of oil and brines. Changes in pH were observed in the low salinity flooding and negligible changes were noticed in the high salinity floods. These results provide an insight into the roles of chloride and sulphate ions in the design of smart “designer” water and low salinity injection scenarios