Effect of Lateral Water Surface Profile on Side Weir Discharge

The average water surface slope in the lateral direction is taken into account as a local parameter ψ to study flow over a side weir. It was later shown that for smaller side weir lengths and side weir portions with no entrance and exit transition effects, ψ can be obtained from a numerical integral and also from the measurements of water surface elevations in the lateral direction. The effect of elemental weir length was further determined. Dividing the weir length into smaller computational segments has the effect of lowering the water surface to approach the measured profile, the downstream ends being coincident. The model was verified using experimental data.     

How to diagnose chronic rejection. A study in porcine intestinal allografts

The conventional Spin-Echo sequences have been the most used acquisition techniques on Magnetic Resonance Imaging (MRI) of the brain, since the beginning of 1990s. Recently, however, technological developments proposed such new fast acquisition techniques, with a dramatic reduction in acquisition time as Gradient Echo, Turbo Spin Echo, Gradient Spin Echo ed Echo Planar sequences. We investigated the comparative adequacy of the new fast sequences, in brain MR studies versus conventional sequences, on medium field strength MR equipment (.5 T). On in vitro exams S/N ratio was evaluated and on in vivo study C/N ratio between white substance grey substance and fluid were evaluated, in 15 healthy volunteers. All the exams were carried out on Philips NT5 Gyroscan MR unit operating at .5 T, with 15 mT/m power gradients. Both conventional and fast sequences Spin-Echo (SE), Inversion Recovery (IR), Gradient-Echo (GE), Turbo Spin-Echo (TSE), Gradient Spin-Echo (GRASE) and Echo Planar (EPI), all optimized to obtain T1, T2 and T1-IR weighted images, were performed. The sequences were evaluated separately comparing different acquisition techniques relative to the same type of contrast (T1, T2, and T1-IR). The results indicate the superiority of the fast acquisition techniques, both in terms of quality and acquisition times, except for T1-weighted images, where the conventional Spin-Echo sequences confirmed to be superior. In conclusion, the present study suggests that fast acquisition techniques can improve the conventional protocol of sequences, in the anatomical representation of the normal brain even with medium field strength equipment only on T2 and T1-IR weighted images. On T1-weighted imaging conventional SE acquisition technique is still the best choice. The time saving obtained with fast sequences can therefore be used for an overall improvement in the quality of images, and to apply accessory acquisition plans on routine exams.     

Evolution of glomerular basement membrane changes in chronic rejection

We have investigated the evolution of chronic glomerular changes in the absence of the recurrence of original disease in an experimental rat model of chronic renal allograft rejection. Using serial graft needle biopsies and serum creatinine levels, we were able to focus on early glomerular changes that are associated with good graft function. The recipient rats were divided into 5 groups, 2 with allogeneic (DA to WF) transplants and 3 with syngeneic (DA to DA) transplants. In the first 2 allogeneic groups, one group received cyclosporine (CsA) for 2 weeks (n = 7) and the other received CsA for 12 weeks (n = 5). In the 2-week treatment group, all allografts developed chronic rejection, compared with none in the 12-week group. Syngeneic controls received CsA for 2 (n = 3) and 12 weeks (n = 3), or no immunosuppression (n = 2) in order to exclude the effects of CsA. The first detectable ultrastructural event was slight deposition of electron lucent material in the glomerular basement membrane. Contrary to previous morphological studies, the initial deposition was not subendothelial, but was within the lamina densa itself. Examination of allogeneic grafts with good graft function and syngeneic grafts showed glomerular alterations that were similar to the early changes preceding chronic rejection. The intensity of changes in optimally immunosuppressed allografts was mild, and they were arrested early in the evolving stage of glomerular basement membrane changes. In the suboptimally immunosuppressed allografts with chronic rejection, the glomerular basement membrane changes became more pronounced and extensive in subsequent biopsies. Thus, all recipients in different groups showed similar glomerular alterations, but to different intensities. These results suggest a common pathogenetic mechanism which might be endothelial damage. In chronic rejection, the endothelial damage might be immunologically mediated by rejection episodes and progressive, whereas in syngeneic grafts and in allografts without chronic rejection, perioperative trauma, ischemia, and graft reperfusion may be responsible for the self-limiting glomerular changes.     

Equations for heating and cooling of bodies of various shapes

Equations for predicting temperatures in solids of various shapes undergoing heating or cooling are presented. The derived equations are compared with the available numerical values obtained for plates, cylinders and spheres. The centre and surface temperatures and the heat transferred can be described with a maximum deviation of −4.3/3.9%, even though the temperature profiles in these bodies are described with a maximum deviation of −6.8/7.6%.     

Dipole moments of styrene/4-vinylpyridine copolymers—II: Relation to microstructure

Mean-square dipole moment values of styrene/4-vinylpyridine (S4VP) copolymers determined at 25–60°C in 1,4-dioxane solutions were related to the microstructure of the chains. Data on the synthesis and dipole moments of S4VP copolymers were used to calculate the distribution of triad fractions and effective dipole moments of styrene, S-centred, and 4-vinylpyridine, V-centred, fractions in the copolymer chains. The relative magnitudes of the effective dipole moment values calculated for each type of triad reflect the effect of dipole–dipole interactions on these values.     

Antioxidant and anticholinesterase evaluation of selected Turkish Salvia species

Since Salvia species (Lamiaceae) have been recorded to be used against memory loss in European folk medicine, we herein examined in vitro anticholinesterase and antioxidant activities of 56 extracts prepared with petroleum ether, chloroform, ethyl acetate and methanol obtained from 14 Salvia species (Salvia albimaculata Hedge and Hub, Salvia aucheri Bentham var. canescens Boiss and Heldr, Salvia candidissima Vahl. ssp. occidentalis, Salvia ceratophylla L., Salvia cryptantha Montbret and Bentham, Salvia cyanescens Boiss and Bal., Salvia frigida Boiss, Salvia forskahlei L., Salvia halophilaHedge, Salvia migrostegia Boiss and Bal., Salvia multicaulis Vahl., Salvia sclarea L., Salvia syriaca L., Salvia verticillata L. ssp. amasiaca) growing in Turkey. The antioxidant activities were assessed by both chemical and enzymatic methods against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging and xanthine/xanthine oxidase (XO) system generated superoxide anion radical inhibition. Anticholinesterase effect of the extracts was tested against both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) at concentrations of 0.2 and 1 mg/ml using a microplate-reader assay based on the Ellman method. Most of the extracts did not show any activity against AChE at 0.2 mg/ml, while the chloroform extracts had noticeable inhibition against BChE between 47.7% and 74.7%. The most active extracts at 1 mg/ml for AChE inhibition were observed to be petroleum ether extract of Salvia albimaculata (89.4%) and chloroform extract of Salvia cyanescens (80.2%), whereas ethyl acetate extracts of Salvia frigida and Salvia migrostegia, chloroform extracts of Salvia candidissima ssp. occidentalis and Salvia ceratophylla, as well as petroleum ether extract of Salvia cyanescens were found to inhibit potently BChE (92.2%, 89.6%, 91.1%, 91.3%, and 91.8%, respectively). Particularly, the ethyl acetate and methanol extracts were observed to be highly active against both DPPH and XO. Our data indicates that nonpolar extracts of Salvia species for anticholinesterase activity and the polar extracts for antioxidant activity are worth further phytochemical evaluation for identifying their active components.     

Effect of harvesting hour on some physical and mechanical properties of Rosa damascena Mill

BACKGROUND: Mechanization of Rosa damascena flower harvest is limited because of the asynchronous flowering period, the necessity for the harvest operation to take place in the early hour of the morning, and a lack of knowledge regarding the physical–mechanical properties of R. damascena. This study investigated the effect of harvesting hour on some physical–mechanical properties of R. damascena. RESULTS: The terminal velocity of the rose flower ranged from 4.00 to 2.38 m s^?1. The highest picking force was found to be 6.29 N for the harvesting hour of 06:00 am. Tear forces of petal changed from 1.54 to 0.97 N for the harvesting hour of 06:00 am and 12:00 pm, respectively. The tension force of pedicel varied between 8.25 and 7.76 N. The weight of the rose flower was measured as an average of 1.61 and 1.50 g at 06:00 am and 12:00 pm, respectively. Horizontal and vertical projection areas of rose flowers were positively correlated with harvesting hour, with an R² of 0.97 and 0.75, respectively. Results showed that there was a minor loss in colour for both inner and outer surfaces of petals. CONCLUSION: The results of physical–mechanical properties of R. damascena obtained from this study should be considered for the operation of flower harvest mechanization. Copyright © 2011 Society of Chemical Industry     

Effect of electroless etching parameters on the growth and reflection properties of silicon nanowires

Vertically aligned silicon nanowire (Si NW) arrays have been fabricated over large areas using an electroless etching (EE) method, which involves etching of silicon wafers in a silver nitrate and hydrofluoric acid based solution. A detailed parametric study determining the relationship between nanowire morphology and time, temperature, solution concentration and starting wafer characteristics (doping type, resistivity, crystallographic orientation) is presented. The as-fabricated Si NW arrays were analyzed by field emission scanning electron microscope (FE-SEM) and a linear dependency of nanowire length to both temperature and time was obtained and the change in the growth rate of Si NWs at increased etching durations was shown. Furthermore, the effects of EE parameters on the optical reflectivity of the Si NWs were investigated in this study. Reflectivity measurements show that the 42.8% reflectivity of the starting silicon wafer drops to 1.3%, recorded for 10 μm long Si NW arrays. The remarkable decrease in optical reflectivity indicates that Si NWs have a great potential to be utilized in radial or coaxial p-n heterojunction solar cells that could provide orthogonal photon absorption and enhanced carrier collection.     

Replacement of aortic root with valved tubular prosthesis in a ten-year-old child with infective endocarditis--a case report

Aortic root abscess, aneurysm of sinus Valsalva, severe aortic valve insufficiency, and a fragile aortic wall caused by infective endocarditis were found in a 10-year-old child. Aortic valve replacement was intended as a preoperative strategy, but one of modifications of Cabrol had to be used urgently because of aortic root rupture between right atrial and aortic connection just after pericardiotomy.     

Allelic loss of 16q23.2-24.2 is an independent marker of good prognosis in primary breast cancer

Allelic loss, detected as a loss of heterozygosity (LOH) on the long arm of chromosome 16, is an early and frequent event in breast cancer. Despite this, the clinical significance of LOH on 16q has been very poorly studied. In this study, corresponding blood and tumor samples from 199 clinically well-characterized primary breast cancer patients were analyzed for LOH with the highly polymorphic microsatellite marker D16S511, located at 16q23.2-24.2. 61% of 168 informative tumors showed LOH. Univariate and multivariate analysis found a highly significant association between LOH at 16q23.2-24.2 and freedom from distant metastases, disease-free survival, and overall survival, respectively. No association was found with other clinical parameters such as menopausal status, tumor size, lymph node status, histopathology, and lymph node capsule invasion. This makes allelic loss of 16q23.2-24.2 an independent marker of good prognosis for primary breast cancer.