38 research outputs found

    A Comparison of Three and Two-Dimensional Analyses of Rockfill Dams in Narrow Valleys (A Case Study: The Vanyar Dam)

    Get PDF
    A two-dimensional analysis of the largest cross-section of earth dams may generate appropriate results provided that the dam is located in a U-shape valley. The Vanyar dam has been constructed in a narrow valley. With regard to the geometrical consideration of the valley, there is no plane strain condition throughout the long side of the dam. In this research, the results of three and two dimensional numerical analyses of the Vanyar dam are compared in terms of settlement, pore water pressure, and total vertical stress. These analyses were carried out by a finite difference method through FLAC-3D and FLAC-2D softwares. In order to verify the results of the analyses, the settlement data recorded by the instruments in the body of the dam are compared to those provided through the numerical analyses. The results of the three and two dimensional analysis show that the settlements in the upper half of the height of the dam have a suitable adaptation. Moreover, the two- dimensional analysis shows the settlements in the lower half of the height of the dam more than those shown by the three-dimensional analysis. Furthermore, in terms of total vertical stress and pore water pressure, the two-dimensional analysis shows the values throughout the height of the dam more than those shown by the threedimensional analysis

    The Investigation of Salinity Effects on Behavioral Parameters of Fine-Grained Soils

    Get PDF
    The present paper aims at investigating the effect of water salinity on engineering properties of fine-grain soil. Saline water used in this study was obtained from half saline water of Ajichay River (with TDS more than 1877 ppm) and saline branch of Korchay (with TDS more than 97000 ppm) located in Northwestern of Iran. Fine-grain soil studied is from Korchay dam core. Due to the high hardness of water in this river, the feasibility of using saline water as the water required in clay core of the dam process has been studied in this research. The experiments were performed including Atterberg limits, standard compaction, consolidation, direct shear and dispersion. These tests were performed by using distilled water, half saline water and saline water on reservoir materials. Due to low percentage of clay minerals in the soil, the changes in engineering soil properties as salinity increases are negligible. However, the use of saline water reduces Atterberg limits, compression index (Cc), swell index (Cs(, coefficient of compressibility (av), coefficient of volume compressibility (mv) and causes slight increase in soil shear strength parameters. Despite the high percentage of sodium in half saline and saline water, dispersion degree of soil is ND2 in pinhole test

    Integrated Management Practices for Establishing Upland Switchgrass Varieties

    Get PDF
    Establishment of switchgrass (Panicum virgatum L.) is challenging, and failure in establishment may expose growers to considerable economic risk. The objectives of this research were to (i) evaluate whether management practices are variety-specific for the establishment of switchgrass and (ii) assess the effectiveness of cover crops as preceding crops on ‘Shawnee’ switchgrass establishment. Therefore, two studies were conducted at the University of Massachusetts Agricultural Experiment Station in Deerfield, MA, USA, in the 2011–2012 and 2012–2013 growing seasons. In Experiment 1, cover crop treatments (fallow, oat (Avena sativa L.) and rye (Secale cereale L.)) were the main plots, the two seeding methods (no-till drill and a cultipacker seeder (Brillion)) were the sub-plots, and the two varieties (‘Cave-in-Rock’ (CIR) and Shawnee)) were the sub-sub-plots. The second study was conducted using Shawnee switchgrass and involved the three cover crop treatments used in Experiment 1 using a cultipacker seeder with seed firming prior to planting but not afterwards (consistent in both experiments). The results indicated that a combination of oat and no-till resulted in higher tiller density (493%), lower weed biomass (77%), increased switchgrass biomass (SGB) (283%) and SGB to weed biomass (WB) ratio. Compared with Shawnee, CIR planted into a winter-killed oat residue had higher tiller density (93%), lower weed biomass (18%), higher switchgrass yield (128%) and thus a greater SGB:WB ratio (507%). Trends of switchgrass response to management practices, however, were similar between the two varieties, indicating that seed quality rather than management practices could influence switchgrass’s response to management practices. In Experiment 2, Shawnee tiller density was suppressed by rye as the preceding crop, possibly due to late termination of rye. Shawnee switchgrass yields were below 1000 kg ha−1 under all management practices; thus, harvesting should happen in the year following establishment. Future research should focus on comparing no-till drilling with cultipacker seeder with rolling not only before but after seeding to increase seed–soil contac

    THE ANTI-OXIDANT EFFECTS OF GINGER AND CINNAMON ON SPERMATOGENESIS DYS-FUNCTIONING DIABETES RATS.

    Get PDF
    Background: Diabetes has being linked to reproductive dysfunction and plant medicine has been shown to be effective in its treatment. Anti-oxidants have distinctive effects on spermatogenesis, sperm biology and oxidative stress, and changes in anti-oxidant capacity are considered to be involved in the pathogenesis of chronic diabetes mellitus. Ginger and cinnamon are strong anti-oxidants and have been shown to reduce oxidative stress in the long-term treatment of streptozotocin (STZ)-induced diabetes in animal models. The present study aims at examining the influence of combined ginger and cinnamon on spermatogenesis in STZ-induced diabetes in male Wistar rats. Materials and Methods: Animals (n = 80) were allocated randomly into eight groups, 10 each: Group 1: Control rats given only 5cc Normal saline (0.9% NaCl) daily;Group2: rats received ginger (100mg/kg/rat) daily; Group 3: rats received cinnamon (75mg/kg) daily; Group 4: rats received ginger and cinnamon, (100mg/kg/rat ginger and 75mg/kg cinnamon) daily; Group 5: Diabetic control rats received only normal saline. Group 6: Diabetic rats received 100mg/kg/day ginger; Group 7: Diabetic rats received 75mg /kg/ day cinnamon; Group 8: Diabetic rats received ginger and cinnamon (100mg/kg/day and 75mg/kg /day). Diabetes was induced with 55 mg/kg, single intra-peritoneal injection of STZ in all groups. At the end of the experiment (56th day), blood samples were taken for determination of testosterone, LH,FSH, total anti-oxidant capacity, and levels of malondialdehyde, SOD, Catalase and GPX. All rats were euthanized, testes were dissected out and spermatozoa were collected from the epididymis for analysis. Results: Sperm numbers, percentages of sperm viability and motility, and total serum testosterone increased in ginger and cinnamon and combined ginger and cinnamon treated diabetic rats compared with control groups. Serum testosterone, LH and FSH were higher compared to control group and also serum anti-oxidants (TAC, SOD, GPX and catalase) all were increased at the end of treatment. Combined ginger and cinnamon showed more intense increase in all parameters compare to ginger and cinnamon alone. Most of the results were significant (

    Suspended sediment modelling by SVM and wavelet

    Get PDF
    Napredak koji danas bilježimo u primjeni umjetne inteligencije za predviđanje hidroloških događaja doveo je do brojnih promjena u sferi predviđanja. Valićni model baziran na metodi potpornih vektora (WSVM) dobiven je spajanjem valićne analize i metode potpornih vektora (SVM). Za učenje i testiranje korišteni su podaci o lebdećem nanosu (SS) i dnevnom protoku (Q) izmjereni na rijeci Iowa u SAD-u. Provedene analize su pokazale da se valićni model WSVM može koristiti za aproksimaciju količine lebdećeg nanosa.Present-day advances in artificial intelligence, as a forecaster for hydrological events, have led to numerous changes in forecasting. The wavelet support vector machine (WSWM) model is achieved by conjunction of the wavelet analysis and the support vector machine (SVM). The suspended sediment (SS) and daily stream flow (Q) data from the Iowa River in the USA were used for training and testing. The WSVM could logically be used for approximation of the suspended sediment load

    Errors of Upright Perception in Patients With Vestibular Migraine

    Get PDF
    Patients with vestibular migraine (VM) often report dizziness with changes in the head or body position. Such symptoms raise the possibility of dysfunction in neural mechanisms underlying spatial orientation in these patients. Here we addressed this issue by investigating the effect of static head tilts on errors of upright perception in a group of 27 VM patients in comparison with a group of 27 healthy controls. Perception of upright was measured in a dark room using a subjective visual vertical (SVV) paradigm at three head tilt positions (upright, ±20°). VM patients were also surveyed about the quality of their dizziness and spatial symptoms during daily activities. In the upright head position, SVV errors were within the normal range for VM patients and healthy controls (within 2° from true vertical). During the static head tilts of 20° to the right, VM patients showed larger SVV errors consistent with overestimation of the tilt magnitude (i.e., as if they felt further tilted toward the right side) (VM: −3.21° ± 0.93 vs. Control: 0.52° ± 0.70; p = 0.002). During the head tilt to the left, SVV errors in VM patients did not differ significantly from controls (VM: 0.77° ± 1.05 vs. Control: −0.04° ± 0.68; p = 0.52). There was no significant difference in SVV precision between the VM patients and healthy controls at any head tilt position. Consistent with the direction of the SVV errors in VM patients, they largely reported spatial symptoms toward the right side. These findings suggest an abnormal sensory integration for spatial orientation in vestibular migraine, related to daily dizziness in these patients

    Cicer arietinum in the Treatment of Small Renal Stones: a Double-Blind, Randomized and Placebo-Controlled Trial

    Get PDF
    Background and objectives: Urolithiasis is a common urological disorder. Based on the Persian medicine literatures, Cicer arietinum has a potential to dissolve renal stones. This study was designed to assess the efficacy and safety of Cicer arietinum in patients with renal stone. Methods: The extract of C. arietinum seeds was spray dried. A randomized, double blind, placebo-controlled study was conducted on 74 patients with 6-10 mm renal stones in ultrasonography. Patients were randomly assigned to take 330 mg of C. arietinum extract or placebo capsules three times a day for 30 days. Complete stone dissolution and the change in stone size during the trial was evaluated by ultrasonography. To assess the efficacy and safety of C. arietinum, blood and urine biochemical parameters were checked at baseline and after the intervention. Results: In the C. arietinum group, complete stone dissolution occurred in 9 (23.7%) patients and reduce in stone size was observed in 17 (44.7%) patients while no response to treatment was observed in placebo group. The mean stone size was reduced from 7.15 ± 1.34 mm to 4.28 ± 3.09 mm in the C. arietinum group (p Conclusion: Cicer arietinum extract could be an effective and safe treatment option for patients with 6-10 mm renal stones

    Carbon-sensitive pedotransfer functions for plant available water

    Get PDF
    Currently accepted pedotransfer functions show negligible effect of management-induced changes to soil organic carbon (SOC) on plant available water holding capacity (θAWHC), while some studies show the ability to substantially increase θAWHC through management. The Soil Health Institute\u27s North America Project to Evaluate Soil Health Measurements measured water content at field capacity using intact soil cores across 124 long-term research sites that contained increases in SOC as a result of management treatments such as reduced tillage and cover cropping. Pedotransfer functions were created for volumetric water content at field capacity (θFC) and permanent wilting point (θPWP). New pedotransfer functions had predictions of θAWHC that were similarly accurate compared with Saxton and Rawls when tested on samples from the National Soil Characterization database. Further, the new pedotransfer functions showed substantial effects of soil calcareousness and SOC on θAWHC. For an increase in SOC of 10 g kg–1 (1%) in noncalcareous soils, an average increase in θAWHC of 3.0 mm 100 mm–1 soil (0.03 m3 m–3) on average across all soil texture classes was found. This SOC related increase in θAWHC is about double previous estimates. Calcareous soils had an increase in θAWHC of 1.2 mm 100 mm–1 soil associated with a 10 g kg–1 increase in SOC, across all soil texture classes. New equations can aid in quantifying benefits of soil management practices that increase SOC and can be used to model the effect of changes in management on drought resilience
    corecore