Is a low sacral ratio associated with primary vesicoureteral reflux in children?

Introduction: The association of sacral anomalies with fecal incontinence and lower urinary tract dysfunction is known. The sacral ratio is proposed as a tool for evaluation of sacral development. The aim of this cross-sectional study was to evaluate the prevalence and severity of vesicoureteral reflux in children with a low sacral ratio. Materials and Methods: Six hundred and sixty nine children who were referred to a radiology clinic for a standard (fluoroscopic) VCUG to detect vesicoureteral reflux and other anomalies of the lower urinary tract after an episode of urinary tract infection were included in the study and their sacral ratios were measured. Results: All children were younger than 14 years of age (mean 3.44±3.20). Of 669 children, 593 (88.6%) had normal sacral ratios out of whom 423 (71.3%) did not have VUR and 170 (28.7%) had VUR. Seventy-six (11.3%) children out of 669 cases had low sacral ratios; 49 (64.5%) of them had no VUR and 27 (35.5%) had VUR. There was no significant difference in the prevalence of VUR between children with and without a low sacral ratio (p value=0.217). Also, there was no significant difference or trend between a low sacral ratio and the severity of reflux (Chi2 for trend). Conclusions: Although sacral anomalies may be related to some cases of VUR by producing lower urinary tract dysfunction, the sacral ratio is not associated with VUR

Counterterms for Static Lovelock Solutions

In this paper, we introduce the counterterms that remove the non-logarithmic divergences of the action in third order Lovelock gravity for static spacetimes. We do this by defining the cosmological constant in such a way that the asymptotic form of the metric have the same form in Lovelock and Einstein gravities. Thus, we employ the counterterms of Einstein gravity and show that the power law divergences of the action of Lovelock gravity for static spacetimes can be removed by suitable choice of coefficients. We find that the dependence of these coefficients on the dimension in Lovelock gravity is the same as in Einstein gravity. We also introduce the finite energy-momentum tensor and employ these counterterms to calculate the finite action and mass of static black hole solutions of third order Lovelock gravity. Next, we calculate the thermodynamic quantities and show that the entropy calculated through the use of Gibbs-Duhem relation is consistent with the obtained entropy by Wald's formula. Furthermore, we find that in contrast to Einstein gravity in which there exists no uncharged extreme black hole, third order Lovelock gravity can have these kind of black holes. Finally, we investigate the stability of static charged black holes of Lovelock gravity in canonical ensemble and find that small black holes show a phase transition between very small and small black holes, while the large ones are stable.Comment: arXiv admin note: text overlap with arXiv:1008.0102 by other author

Thermodynamics, phase transitions and Ruppeiner geometry for Einstein-dilaton Lifshitz black holes in the presence of Maxwell and Born-Infeld electrodynamics

In this paper, we first obtain the ($n+1$)-dimensional dilaton-Lifshitz black hole (BH) solutions in the presence of Born-Infeld (BI) electrodynamics. We find that there are two different solutions for $z=n+1$ and $z\neq n+1$ cases ($z$ is dynamical critical exponent). We show that the thermodynamics first law is satisfied for both cases. Then, we turn to study different phase transitions (PTs) for our BHs. We start with study of Hawking-Page PT for both linearly and BI charged BHs. After that, we discuss the PTs inside the BHs. We present the improved Davies quantities and prove that the PT points shown by them coincide with Ruppeiner ones. We show that the zero temperature PTs are transitions on radiance properties of BHs by using Landau-Lifshitz theory. Next, we turn to study Ruppeiner geometry of linearly and BI charged BHs. For linearly charged case, we show that there are no PT at finite temperature for the case $z\geq 2$. For $z<2$, it is found that the number of finite temperature PT points depends on the value of BH charge and is not more than two. When we have two finite temperature PT points, there are no thermally stable BH between these two points and we have discontinues small/large BH PTs. As expected, for small BHs, we observe finite magnitude for Ruppeiner invariant which shows the finite correlation between possible BH molecules while for large BHs, the correlation is very small. Finally, we study the Ruppeiner geometry and thermal stability of BI charged Lifshtiz BHs for different values of $z$. We observe that small BHs are thermally unstable in some situations. Also, the behavior of correlation between possible BH molecules for large BHs is the same as linearly charged case. In both linearly and BI charged cases, for some choices of parameters, the BH systems behave like a Van der Waals gas near transition point.Comment: V2: 23 pages (revtex format), 13 figures (except one, all include subfigures), some references adde

The new class of A-stable hybrid multistep methods for numerical solution of stiff initial value problem

In this paper, we present a class of   hybrid multistep methods for the numerical solution of first-order initial value problems. We have used second derivative of solution (similar to second derivative multistep methods of Enright) and  an off-step point. The accuracy and stability analysis are discussed. Stability domains of our presented methods have been obtained?, ?showing that this class of efficient numerical methods are A))-stable of order up to 10. Numerical results are also given for four test problems?. Keywords: Initial value problems, Multistep methods, Off-step point, Stability aspects

Lovelock Thin-Shell Wormholes

We construct the asymptotically flat charged thin-shell wormholes of Lovelock gravity in seven dimensions by cut-and-paste technique, and apply the generalized junction conditions in order to calculate the energy-momentum tensor of these wormholes on the shell. We find that for negative second order and positive third order Lovelock coefficients, there are thin-shell wormholes that respect the weak energy condition. In this case, the amount of normal matter decreases as the third order Lovelock coefficient increases. For positive second and third order Lovelock coefficients, the weak energy condition is violated and the amount of exotic matter decreases as the charge increases. Finally, we perform a linear stability analysis against a symmetry preserving perturbation, and find that the wormholes are stable provided the derivative of surface pressure density with respect to surface energy density is negative and the throat radius is chosen suitable.Comment: 13 pages, 6 figure

Protozoans; (Coccidia and Myxosporea;) infections in some fishes of Aras and Mahabad Dams (Northwest of Iran)

During a protozoological study on the fishes of West-Azarbayejan province (Northwest of Iran) in 1998, three different protozoans were revealed. Myxobolus musayevi from Capoeta capoeta, Myxobolus dispar from Aspius aspius taeniatus and Goussia carpelli from Cyprinus carpio. Altogether 13 different fish specimen were examined. The fishes including: Aspius aspius taeniatus (2), Rutilus ruti/us (3), Capoeta cpoeta (2) and Cyprinus carpio (6). They were caugth from Aras and Mahabad Dams and transported alive to the laboratory where they were wieghted and measured. Then, they were examined for protozoan infections when their spinal cord was cut. Myxobolus musayevi had already reported from Capoeta capoeta from Taj an in Mazandaran province. This is the first record of Myxobolus dispar from Aspius aspius taeniatus from Iranian freshwaters. Goussia carpelli also had already recorded (unpublished) from the Cyprinus carpio from Sepeedroud River in Guilan province. In this study, three of C. carpio which were caught from Aras Dam had been infected by the oocyst of the Goussia carpelli in the mocus of the intestine

Black Holes in (Quartic) Quasitopological Gravity

We construct quartic quasitopological gravity, a theory of gravity containing terms quartic in the curvature that yields second order differential equations in the spherically symmetric case. Up to a term proportional to the quartic term in Lovelock gravity we find a unique solution for this quartic case, valid in any dimensionality larger than 4 except 8. This case is the highest degree of curvature coupling for which explicit black hole solutions can be constructed, and we obtain and analyze the various black hole solutions that emerge from the field equations in $(n+1)$ dimensions. We discuss the thermodynamics of these black holes and compute their entropy as a function of the horizon radius. We then make some general remarks about $K$-th order quasitopological gravity, and point out that the basic structure of the solutions will be the same in any dimensionality for general $K$ apart from particular cases.Comment: LaTex, 9 figures, 27 pages. A new section on holographic hydrodynamics is added. Introduction and concluding remarks have been revise

Monogenean infestations of arowana (Osteoglossum bicirrhosum) and cat fish (Hypostomus plecostomus)

Arowana (Osteoglossum bicirrhosum) and cat fish (Hypostomus plecostomus) are two species of ornamental fishes which are mostly imported to Iran. Monogenea are plathyhelminthes [sic] which can dominantly infest the fish skin and gills with high host specificity. In this research, 35 O. bicirrhosum and 50 H. plecostomus with clinical signs were collected from different ornamental fish markets in Semnan, Iran and transferred alive to the Lab. Fish skin and gills were examined for monogenean infestations. No monogenea was observed on the skin specimens, but Gonocleithrum cursitans and Unilatus unilatus infested 54.28% and 74% of gills in O. bicirrhosum and H. plecostomus, respectively. This is the first report of both G.cursitans and U. unilatus in Iran

Vincristine Induced Neurotoxicity: Study of 75 Cases

ObjectiveConcern for side-effects of therapy related to treatment of childhood malignancies is becoming an increasingly important topic. In this study, we evaluated extent of vincristine (VCR) induced neurotoxicity in a group of children who underwent chemotherapy, with VCR being part of the regimen.Materials &amp; MethodsIn this investigation, for 75 children (54% boys, 46% girls), aged between 1 to 14 (mean 6.5±4.3) years, serial weekly neurological examinations were performed; of the 75, 70 had acute lymphoblastic leukemia and 5 Wilm's tumor. All patients were on a chemotherapy protocol of at least 4 consecutive VCR (1.5mg/m2) injections.ResultsDecreased deep tendons reflexes were seen in the Achilles reflex in 78%, and the patellar reflex in 53% of patients. Muscle weakness was found in 70% of patients, being mild in 76% of them. Four  percent of patients showed severe weakness. Petosis, jaw pain, hoarseness, abdominal pain and constipation were seen in 15%, 6%, 12%, 12% and 12% respectively. Paresthesia was observed in 32 of 52 patients, over 4 years old. No cases of foot drop, urinary retention or facial nerve palsy were seen in this patient group.ConclusionChildren on usual doses of vincristine regimen may have neuropathic side effects but most of these side effects are mild and not troublesome.

Evaluating droplet distribution of spray-nozzles for dust reduction in livestock buildings using machine vision

Previous studies have demonstrated the negative effects of sub-optimal air quality on profitability, production efficiency, environmental sustainability and animal welfare. Experiments were conducted to assess potential environmental improvement techniques such as installing oil-spraying systems in piggery buildings. The developed spray system worked very well and it was easy to assemble and operate. However, before selecting the most suitable spray heads, their capacity to uniformly distribute the oily mixture and the area covered by the spray heads had to be assessed. Machine vision techniques were used to evaluate the ability of different spray heads to evenly distribute the oil/water mixture. The results indicated that the best coverage was achieved by spray head No.4 and spray head No.1 which covered 79% and 67% of the target area, respectively. Spray distribution uniformity (variance) value was the lowest for spray head No.4 (0.015). Spray head No.3 had the highest variance value (0.064). As the lowest variance means higher uniformity, nozzle No.4 was identified as the most suitable spray head for dust reduction in livestock buildings