190 research outputs found

    A parameter-robust finite difference method for singularly perturbed delay parabolic partial differential equations

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    AbstractA Dirichlet boundary value problem for a delay parabolic differential equation is studied on a rectangular domain in the x-t plane. The second-order space derivative is multiplied by a small singular perturbation parameter, which gives rise to parabolic boundary layers on the two lateral sides of the rectangle. A numerical method comprising a standard finite difference operator (centred in space, implicit in time) on a rectangular piecewise uniform fitted mesh of Nx×Nt elements condensing in the boundary layers is proved to be robust with respect to the small parameter, or parameter-uniform, in the sense that its numerical solutions converge in the maximum norm to the exact solution uniformly well for all values of the parameter in the half-open interval (0,1]. More specifically, it is shown that the errors are bounded in the maximum norm by C(Nx-2ln2Nx+Nt-1), where C is a constant independent not only of Nx and Nt but also of the small parameter. Numerical results are presented, which validate numerically this theoretical result and show that a numerical method consisting of the standard finite difference operator on a uniform mesh of Nx×Nt elements is not parameter-robust

    Robust numerical methods for boundary-layer equations for a model problem of flow over a symmetric curved surface

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    We investigate the model problem of flow of a viscous incompressible fluid past a symmetric curved surface when the flow is parallel to its axis. This problem is known to exhibit boundary layers. Also the problem does not have solutions in closed form, it is modelled by boundary-layer equations. Using a self-similar approach based on a Blasius series expansion (up to three terms), the boundary-layer equations can be reduced to a Blasius-type problem consisting of a system of eight third-order ordinary differential equations on a semi-infinite interval. Numerical methods need to be employed to attain the solutions of these equations and their derivatives, which are required for the computation of the velocity components, on a finite domain with accuracy independent of the viscosity, which can take arbitrary values from the interval (0, l]. To construct a robust numerical method we reduce the original problem on a semi-infinite axis to a problem on the finite interval [O,K], where K = K(N) = ln N. Employing numerical experiments we justify that the constructed numerical method is parameter robust

    The effect of traditional dysphagia therapy on the swallowing function in patients with Multiple Sclerosis: A pilot double-blinded randomized controlled trial

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    Background: Dysphagia is common following Multiple Sclerosis (MS) and is associated with significant morbidity and mortality. The current rehabilitation program to swallowing therapy is Traditional Dysphagia Therapy (TDT), but there is a dearth of evidence about its effectiveness in MS patients. Objectives: This study was aimed to determine the effects of the TDT on the swallowing function in MS patients with dysphagia. Methods: A pilot double blind randomized clinical trial was carried out on 20 patients with MS. Patients were randomly divided into experimental group (TDT) comprising sensorimotor exercises and swallowing maneuvers, and Usual Care (UC) comprising diet prescription and postural changes. Patients in both groups received treatments for 6 weeks, 18 treatment sessions, 3 times per week, every other day. The Mann Assessment of Swallowing Ability (MASA) was the main outcome measure. The swallowing ability was assessed before treatment (T 0 ), after the end of 9th session (T 1 ), after the end of 18th session (T 2 ), and after 6 weeks follow-up (T 3 ). Penetration�Aspiration Scale (PAS) and Pharyngeal Residue Rating Scale (PRRS) as secondary outcome measures were applied at T 0 and T 2 . Results: Both groups had improved regarding MASA, PAS and PRRS scores over the time (P < 0.001). The improvements achieved in all outcomes were significantly greater in the TDT group than those of the UC group. The Main effect of the Time � Group interaction was significant for MASA score (P < 0.001). The large effect sizes were found for MASA score in both the TDT (d = 3.91) and the UC (d = 1.11) groups. Conclusions: This pilot randomized controlled trial showed that the TDT significantly improved the swallowing function of the MS patients with dysphagia. © 2018 Elsevier Lt

    Development, cross-cultural adaptation, and psychometric characteristics of the persian progressive aphasia language scale in patients with primary progressive aphasia: A pilot study

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    Introduction: Primary Progressive Aphasia (PPA) is a neurological condition characterized by progressive dissolution of language capabilities. The Progressive Aphasia Language Scale (PALS) is an easy-to-apply bedside clinical scale capable of capturing and grading the key language features essential for the classification of PPA. The objective of the present study was to develop and validate the Persian version of the PALS (PALS-P) as a clinical language assessment test. Methods: In this cross-sectional study, PALS was translated and adapted into Persian according to the international guidelines. A total of 30 subjects (10 subjects with PPA and 20 control subjects without dementia) were recruited to evaluate the intra-rater reliability and discriminant validity of PALS-P. Results: The intra-rater reliability of the PALS-P within a 14-day interval was excellent for each subtest (ICC agreement range=0.81-1.0). PALS-P results were statistically significant among groups, suggesting its discriminative validity. Conclusion: This preliminary study indicates that PALS-P was successfully developed and translated. It seems to be a valid and reliable screening tool to assess language skills in Persian-speaking subjects with progressive aphasia

    Soil analysis gis-based fertility assessment and mapping of agricultural research station, Pakhribas, Dhankuta, Nepal

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    Soil fertility evaluation has been considered as a most effective tool for sustainable planning of a particular region. This study was conducted to determine the soil fertility status of the Agricultural Research Station, Pakhribas, Dhankuta, Nepal. The total 60 soil samples were collected randomly at a depth of 0-20 cm by using the soil sampling auger. For identification of soil sampling points A GPS device was used. The collected samples were analyzed for their texture, pH, OM, N, P2O5, K2O, Ca, Mg, S, B, Fe, Zn, Cu and Mn status following standard methods in the laboratory of Soil Science Division, Khumaltar. The Arc-GIS 10.1 software was used for soil fertility maps preparation. The observed data revealed that soil was dark yellowish brown (10YR 4/4) and yellowish brown (10YR 5/6) in colour, and single grained, granular and sub-angular blocky in structure. The sand, silt and clay content were 56.61±0.97%, 27.62±0.56% and 15.77±0.58%, respectively and categorized as loam, sandy loam and sandy clay loam in texture. The soil was very acidic in pH (4.66±0.07) and very low in available sulphur (0.53±0.11mg/kg), available boron (0.24±0.07mg/kg). The organic matter (1.34±0.07%), total nitrogen (0.09±0.003mg/kg), available calcium (605.70±31.40mg/kg), available magnesium (55.96±4.67mg/kg) and available zinc (0.54±0.22mg/kg) were low in status. Similarly, available potassium (115.98±9.19 mg/kg) and available copper (1.13±0.09 mg/kg) were medium in status. Furthermore, available manganese (36.31±2.82mg/kg) was high, whereas available phosphorus (105.07±9.89 mg/kg) and available iron (55.80±8.89 mg/kg) were very high in status. The soil fertility management practice should be adopted based on the determined status in the field for the sustainable production of crops. The future research strategy should be built based on the soil fertility status of the research farm

    The combined expression of solute carriers is associated with a poor prognosis in highly proliferative ER+ breast cancer

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    Purpose: Breast cancer (BC) is a heterogeneous disease characterised by variant biology, metabolic activity, and patient outcome. Glutamine availability for growth and progression of BC is important in several BC subtypes. This study aimed to evaluate the biological and prognostic role of the combined expression of key glutamine transporters, SLC1A5, SLC7A5 and SLC3A2 in BC with emphasis on the intrinsic molecular subtypes. Methods: SLC1A5, SLC7A5 and SLC3A2 were assessed at the protein level, using immunohistochemistry on tissue microarrays constructed from a large well characterised BC cohort (n=2,248). Patients were stratified into accredited clusters based on protein expression and correlated with clinicopathological parameters, molecular subtypes, and patient outcome. Results: Clustering analysis of SLC1A5, SLC7A5 and SLC3A2 identified three clusters Low SLCs (SLC1A5-/SLC7A5-/SLC3A2-), High SLC1A5 (SLC1A5+/SLC7A5-/SLC3A2-) and High SLCs (SLC1A5+/SLC7A5+/SLC3A2+) which had distinct correlations to known prognostic factors and patient outcome (p<0.001). The key regulator of tumour cell metabolism, c-MYC, was significantly expressed in tumours in the High SLCs cluster (p<0.001). When different BC subtypes were considered, the association with the poor outcome was observed in the ER+ high proliferation/luminal B class only (p= 0.003). In multivariate analysis, SLC clusters were independent risk factor for shorter breast cancer specific survival (p= 0.001). Conclusion: The co-operative expression of SLC1A5, SLC7A5 and SLC3A2 appears to play a role in the aggressive subclass of ER+ high proliferation/ luminal BC, driven by c-MYC, and therefore have the potential to act as therapeutic targets, particularly in synergism

    E2A/PBX1, MLL/AF4, BCR/ABL (M-BCR), BCR/ABL(m-BCR) gene rearrangements in acute lymphoblastic leukemia in Iranian children

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    Objectives: The following observation was primarily based on the study of gene fusion in blood and bone marrow cells taken from 68 Iranian children with acute lymphoblastic leukemia (ALL), to compare with healthy population. Methods: Peripheral blood and bone marrow samples obtained from patients with ALL were immunophenotyped to determine the lineage and the level of differentiation. With reverse transcriptase-polymerase chain reaction (RT-PCR), the RNA molecules were analyzed according to Van Dongen et al. protocol to detect fused genes in cell population. Results: Leukemic cell type was identified by cytochemical stains and classified on the basis of FAB classification. Nonetheless the frequencies of E2A/PBX1, MLL/AF4, BCR/ABL (M-BCR) and BCR/ABL(m-BCR) gene transcripts were 1.5, 0, 0 and 4.4 respectively. The positive case of E2A/PBX1 fusion gene had an early pre B and 3 BCR/ABL (m-BCR). Positive cases had an early pre B and pre-B ALL immunophenotype. Conclusions: Early pre-B cells were the most common types in our patients. The RT-PCR was shown to be an ideal method for detecting hybrid transcripts and to estimate the prevalence of the fusion genes in ALL patients. The frequency of these fusion genes in Iranian pediatric ALL patients were found to be similar to some developed countries. Thus, their presence does not seem to be predictive of increasing malignancy, but rather it can challenge the prognostic significance of these rearrangements. © 2018, Holder Demo

    Study and research on the fishing gears in northern waters of Persian Gulf (Khuzestan Province Coastal Waters)

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    Study and research on the fishing gears in northern waters of Persian Gulf (Khuzestan Province Coastal Waters) was carried out from March 2009 to February 2010. Sampling was done for trawl in summer and autumn, for purse seine in autumn and for gillnet and trap in all seasons. The average of total catch was in trawl 167.9 1.06 kg. The rate of bycatch in ± 207.89 and trap 1.66 ±270.17, gillnet 275.86 ± 48.4, purse seine 1795.6 ± trawl net was 87 percent, purse seine net 30.49 percent, gill net 70 percent and trap 6.19 percent. In this study, the number of bycatch species in trawl net are 38 species, gill net 36 species, trap 10 species and purse seine net 4 species. The result of two way ANOVA test in trawl net between bycatch and time, and between bycatch and place showed non-significant differences (p>0.05, f=0.3) (p>0.05, f=0.9). The result of two way ANOVA test in gillnet between bycatch and time, showed significant (p0.05, f=1.8). The result of two way ANOVA test in trap between bycatch and time and between bycatch and place was non-significant (p>0.05, f=0.5). According to the result, rate of bycatch of trawl net is higher than other gear, so control and manage of bycatch in trawl is most important

    Development, cross-cultural adaptation, and psychometric characteristics of the persian progressive aphasia language scale in patients with primary progressive aphasia: A pilot study

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    Introduction: Primary Progressive Aphasia (PPA) is a neurological condition characterized by progressive dissolution of language capabilities. The Progressive Aphasia Language Scale (PALS) is an easy-to-apply bedside clinical scale capable of capturing and grading the key language features essential for the classification of PPA. The objective of the present study was to develop and validate the Persian version of the PALS (PALS-P) as a clinical language assessment test. Methods: In this cross-sectional study, PALS was translated and adapted into Persian according to the international guidelines. A total of 30 subjects (10 subjects with PPA and 20 control subjects without dementia) were recruited to evaluate the intra-rater reliability and discriminant validity of PALS-P. Results: The intra-rater reliability of the PALS-P within a 14-day interval was excellent for each subtest (ICC agreement range=0.81-1.0). PALS-P results were statistically significant among groups, suggesting its discriminative validity. Conclusion: This preliminary study indicates that PALS-P was successfully developed and translated. It seems to be a valid and reliable screening tool to assess language skills in Persian-speaking subjects with progressive aphasia

    Determination of biomass of fishes in Shadegan Wetland

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    Biomass estimation of fishes were done by depletion method in Shadegan Wetland in 2011-12. Fishing effort and landing catch amount per unit effort was done via random oversea in fixed landing area monthly. Fishermen and catch statistics were obtained from census. Total catch was calculated from multiplication of effort and average catch. Fishes biological characteristics survey indicated that Golden barb (Barbus luteus) and Berzem (Barbus pectoralis) has maximum (62 kg/ha) and minimum (4 kg/ha) biomass respectively. Maximum and Minimum biomass was in spring (380 kg/ha) and in winter (58 kg/ha) respectively and mean biomass was estimated 249 kg/ha in whole area during one year. Number of fishermen were about 1317 and maximum fishing effort was in April, May and June. Total fish landing was 4300 tons per year in which 1119 tons was calculated in April. Large scaled barb (Barbus grypus) and Abu mullet (liza abu) had maximum and minimum mean length and weight. The range length of most of fishes was low and their spawning season was in winter and spring. Length- weight relationship indicates their isometric growth. Despite of 45% decrease of number of fisherman to previous time (2008), catch effort and exploitation was increased (20%). Regarding fish living area (70000 ha), total biomass was 17430 tons
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