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This study presents, a numerical method for the solutions of the generalized nonlinear Benjamin-Bona-Mahony-Burgers' equation, with variable order local time fractional derivative. This derivative is expressed as a product of two functions, the usual integer order time derivative, and a function of time having a fractional exponent. Then, forward difference approximation is used for time derivative. The unknown solution of the differential problem and corresponding derivatives are estimated using Haar wavelet approximations (HWA). The collocation procedure is then implemented in HWA, to transform the given model to the system of linear algebraic equations for the determination of unknown constant coefficient of the Haar wavelet series, which update the derivatives and the numerical solutions. The sufficient condition is established for the stability of the proposed technique, and then verified computationally. To check the performance of the scheme, few illustrative examples in one and two dimensions along with l ∞ and l 2 error norms are also given. Besides this, the computational convergence rate is calculated for both type equations. Additionally, computed solutions are compared with available results in literature. Simulations and graphical data discloses, that suggested scheme works well for such complex problems. [ABSTRACT FROM AUTHOR]

Compound parabolic collectors (CPC) are non-tracking concentrators capable of producing lower to medium-range heating (temperature range of 50–80 °C), making them suitable for space heating applications. CPCs raise the heat transfer fluid temperature to a specific value depending upon the solar irradiation received at the location. In this study, CPC is used to harness the solar energy, and an insulated tank is used to store thermal energy. To facilitate space heating, the hot fluid from the thermal storage tank is passed through a radiator, transferring the thermal energy from the tank to the target heating load. The overall setup consists of two loops with water as heat transfer fluid. Both loops consist of a pump that uses solar PV power. An experimental test setup was installed to measure the ambient heat transfer fluid, radiator fin, and room temperature. The combined system was tested for its performance under actual weather conditions prevailing in the area. Experiments were performed to investigate space heating potential at night, evening, and full day. The energy stored and collector efficiency were calculated for each day. The total thermal energy stored in the tank on a typical day was 67.79 MJ, and the collector efficiency was evaluated to be around 43.7 %. As per the experiment results, the combined CPC and radiator system have a significant potential to be explored in space heating. • Experimental analysis of a space heating system based on CPC is presented. • Sizing of the solar PV system for driving the water pumps is carried out. • System maintains room temperatures between 18°C and 21 °C in winter season. • Results show that the average collector efficiency can reach up to 47.1 %. • Total thermal energy stored in the tank on a typical day can reach 63.7 MJ. [ABSTRACT FROM AUTHOR]

In this paper, meshless RBFs method is proposed to solve two-dimensional time-fractional Sobolev equations. The proposed method uses RBFs for approximation of spatial operator. Finite difference formula of O (δ t 2 − α) (0 < α ≤ 1) is used for time-fractional derivative approximation while θ -rule (0 ≤ θ ≤ 1) as time stepping scheme for the advancement of solution in time. Validation of the proposed method is made by considering various test examples from literature. Simulated results are found in very good agreement with available exact solutions. A rigorous comparative analysis made with other methods testifies proposed method's superiority in higher dimensions. Efficiency and accuracy of RBFs method are examined by varying number of nodes N in the domain of influence, time-step size δ t , as well as L 2 , L ∞ and L rms error norms. Linearized stability analysis of the proposed method is thoroughly discussed and verified numerically to support the analysis. [ABSTRACT FROM AUTHOR]

Highlights • Advection-diffusion problems with multi-term time-fractional derivatives and of variable coefficients are considered in higher dimensions. • These problems have applications mainly in heat conduction or heat transfer, mass and chemical transports into porous or nonporous media. • A meshless spectral radial point interpolation method (MSRPIM) using radial basis functions (RBFs) and point interpolation, is proposed and implemented for obtaining accurate solutions of these problems. • Stability analysis of the proposed method is carried out which is justified computationally. • Computed solutions obtained via different RBFs are matched with each other as well matched with the exact and earlier works for various fractional order derivatives. Comparisons reveal accuracy and efficiency of the proposed method in obtaining accurate solutions for such problems. Abstract In this paper, a weighted meshless spectral radial point interpolation method (MSRPIM) is implemented for the numerical solutions of a class of multi-term time fractional advection-diffusion problems with spatial and temporal dispersion. In the proposed methodology, meshless shape functions are used for discretization in space. These functions are generated via radial basis functions (RBFs) and point interpolation method. Weighted θ -scheme and first order finite differences together with a simple quadrature rule are employed for the discretization of time fractional derivatives. Efficiency and accuracy of the formulated method is validated in terms of number of nodal points N , time-step size τ and weight parameter θ ∈ [ 0 , 1 ]. Quality of the computed solutions are checked using E ∞ , E 2 and E rms error norms. Stability of the proposed method is analyzed theocratically and validated computationally, which is an important task of the current paper. Simulations reveal very good accuracy for both 1D and 2D test problems having constants and variable coefficients. [ABSTRACT FROM AUTHOR]

Abstract In this article, an efficient and accurate meshless spectral interpolation method is formulated for the numerical solution of time-fractional coupled KdV equations that govern shallow water waves. Meshless shape functions constructed via radial basis functions (RBFs) and point interpolation are used for discretization of the spatial operator. Approximation of fractional temporal derivative is obtained via finite differences of order O (τ 2 − α) and a quadrature formula. The formulated method is applied to various test problems available in the literature for its validation. Approximation quality and efficiency of the method is measured via discrete error norms E 2 , E ∞ and E rms. Convergence analysis of the proposed method in space and time is numerically determined by varying nodal points M and time step-size τ respectively. Stability of the proposed method is discussed and affirmed computationally, which is an important ingredient of the current study. [ABSTRACT FROM AUTHOR]

The current work aims to exploit two techniques namely: Residual Power Series method (RPSM) and collocation based meshfree method, for the solution of time-fractional Black–Scholes models with constant and variable coefficients. Firstly, using RPSM, we obtain exact solutions of the considered models and then numerical solution by meshfree method. Computer simulations are performed for three test problems of European options pricing. The simulations features excellent agreement with exact solutions. Accuracy and efficiency of the proposed numerical method is assessed via E 2 , E ∞ and E rms error norms. Convergence of the proposed methods is also analyzed. [ABSTRACT FROM AUTHOR]

Root–knot nematodes ( Meloidogyne spp.) are major pests of vegetables especially in the tropics and subtropics. All commercial okra varieties are susceptible to root knot nematodes and cause substantial losses. The objective of this study is to find out resistant germplasm in order to facilitate our breeders for gene manipulation. A greenhouse study was conducted to evaluate 28 okra cultivars against Meloidogyne incognita inoculated with 5000 eggs. Five cultivars (Bamya Yalova, 19,232, 19,236, 1,922,121, and Green Wonder) had significantly fewer root galls and eggs and less reduction in plant growth (shoot weight and root length), than most of the other entries. A positive relationship was demonstrated between root galls and reduction in plant growth parameters measured. These cultivars may improve okra production in fields infested with M . incognita . During our study, none of the cultivars tested were observed to be immune or resistant to nematode infection according to a scale where: good host [susceptible] when Pf/Pi (Pf = Final population of nematodes after harvest and Pi = Initial population of nematodes which was used as inoculum during experiment) > 5.0, fair, better [moderately resistant] if 5.0 ≥ Pf/Pi > 1, poor if 1 > Pf/Pi > 0, and non-host [resistant] when Pf/Pi = 0. The cultivars, including 19,224, 19,235, Pusa Sawami, Ikra-1, Ikra-2 and Sabzperi China Red, were found to be susceptible with Pf/Pi > 5.0, and they were declared as good hosts of M . incognita . While all the other cultivars were moderately resistant, with 0 ≥ Pf/Pi > 1 but still a significant penetration of nematodes was found. The regression studies showed positive and significant relationships between the number of galls and the reduction in shoot weight ( r 2 = 0.95), number of galls and reduction in shoot length ( r 2 = 0.81), and number of galls and decrease in root length ( r 2 = 0.89). [ABSTRACT FROM AUTHOR]

Octopus-like side chains are introduced in poly(arylene piperidinium)-based alkaline anion exchange membranes (AEMs) to enhance the conductivity and stability. This type of side chain consists of a bulky rigid β-cyclodextrin (β-CD) as the "octopus head", and long flexible piperidinium ionic liquids as the "arms". The β-CD unit can enlarge internal free volume of the AEM to reduce ion transport resistance; the "arms" can interact with adjacent hydrophilic ionic groups and water, constructing continuous ion transport channels. The prepared poly(biphenyl piperidinium) AEM with "octopus" side chains at an ion exchange capacity (IEC) of 1.29 mmol g−1 exhibits higher hydroxide conductivity (121.5 mS cm−1 at 80 °C) than that without the "octopus" structure (57.4 mS cm−1) although the latter has a larger IEC (1.55 mmol g−1). This "octopus" AEM retains 87.2% of its conductivity after being treated in a 1 M NaOH at 80 °C for 480 h. The alkaline H 2 /O 2 fuel cell constructed with this "octopus" AEM produces a peak power density of 469 mW cm−2; the cell voltage can be maintained by 85% during 16 h operation. This work illustrates the advantage of "octopus" side chain for enhancement of AEM performance. [Display omitted] • Octopus-like side chains are grafted on an ether-free backbone for AEM preparation. • The octopus-type side chains can promote micro-phase separation. • The octopus side chain AEM exhibits a high hydroxide ion conductivity (121.5 mS cm−1 at 80 °C). • The H 2 –O 2 fuel cell employing the above AEM yields a power density of 469 mW cm−2 at 60 °C. [ABSTRACT FROM AUTHOR]

In this article, we focus on the numerical study of one and two dimensional higher order multi-term time fractional partial differential equations. In the adopted strategy, the temporal fractional derivative is replaced via well known L 1 formula and the integer order space derivatives are approximated by truncated one and two dimensional wavelet series. The fascinating nature of the scheme is to use collocation approach which convert the governing equations to the system of algebraic equations from which the wavelet coefficients can be calculated. Next, stability of the proposed scheme is investigated theoretically which is also the fundamental subject of the current work. Further computational convergence rate is computed which predicts that the order is approximately two. The scheme is applied to solve one dimensional beam models (fourth order partial differential equations) and two dimensional fissured rock models (Sobolev equations). Efficiency of the scheme is examined with the help of various error norms such as I ∞ , I r m s and I 2. Simulations indicate pretty much good results from which we can say that the scheme is suitable and robust for both one and two dimensional problems. [ABSTRACT FROM AUTHOR]

A numerical scheme based on Haar wavelets coupled with finite differences is suggested to study variable order time fractional partial differential equations (TFPDEs). The technique is tested on (1 + 1)-dimensional advection dispersion and (1 + 2)-dimensional advection diffusion equations. In the proposed scheme, time fractional derivative is firstly approximated by quadrature formula, and then finite differences are combined with one and two dimensional Haar wavelets. With the help of suggested method the TFPDEs convert to a system of algebraic equations which is easily solvable. Also convergence of the proposed scheme has been discussed which is an important part of the present work. For validation, the obtained results are matched with earlier work and exact solutions. Computations illustrate that the proposed scheme has better outcomes. [ABSTRACT FROM AUTHOR]

Abstract This work addresses, numerical method based on Haar wavelets and finite differences to solve two dimensional linear, nonlinear Sobolev and non-linear generalized Benjamin–Bona–Mahony–Burgers (NGBBMB) equations. The temporal part is discretized using finite differences while spatial part is approximated by two dimensional Haar wavelets. With this strategy, computing solution of two dimensional PDEs reduces to computing solution of linear system of algebraic equations. Collocation approach is then applied to determine the wavelet coefficients from linear system. This paper shows that two dimensional Haar wavelets are suitable and effective for two dimensional linear and non-linear PDEs. For validation of the proposed scheme different problems have been solved and error norms L ∞ , L 2 are computed. Computation verifies that current scheme has good outcome. [ABSTRACT FROM AUTHOR]

Objective: To measure physical and neurologic impact of Haemophilus influenzae type b (Hib) meningitis on surviving children through short- and long-term follow-up. Study design: Cases of Hib meningitis, diagnosed at a tertiary level pediatric hospital, were subjected to short- and long-term follow-up and compared with age, sex, and area of residence matched healthy controls. Follow-up assessments included thorough physical and neurodevelopmental assessments using a standardized protocol by a multidisciplinary team. Results: Assessments of short-term follow-up cohort (n = 64) revealed hearing, vision, mental, and psychomotor deficits in 7.8%, 3%, 20%, and 25% of the cases, respectively. Deficits were 10%, 1.4%, 21%, and 25% in long-term follow-up cohort (n = 71), in that order. Mental and psychomotor deficits were found in 2% of the controls, none of whom had vision or hearing deficits. Conclusions: In addition to risk of death, Hib meningitis in children causes severe disabilities in survivors. These data facilitated a comprehensive understanding of the burden of Hib meningitis, specifically in developing countries where disabled children remain incapacitated because of lack of resources and facilities. The evidence generated from this study is expected to provide a compelling argument in favor of introduction and continuation of Hib conjugate vaccine in the national immunization program for children. [Copyright &y& Elsevier]

Anion exchange membranes (AEMs) are an important component in anion exchange membrane fuel cells, and their side chain structures have a significant impact on membrane performance. Here, we construct a series of poly(phenylene oxide) (PPO)-based AEMs with varied side chain structures and investigate the effects of alkyl or alkoxyl extenders (or "tail" of the cation) and spacers (or the link between backbone and cation head group) on AEM performance. Our investigations demonstrate that the simultaneous introduction of alkoxyl extender and spacer can significantly improve water absorption and ion conductivity of membrane; this is attributed to the good hydrophilicity of alkoxyl group and flexibility of spacer that benefit the formation hydrophilic domains. At an IEC (ion exchange capacity) of 1.13 mmol/g, the AEM containing both spacer and alkoxyl extender exhibits a hydroxide conductivity of 87.3 mS/cm (80 °C), which is much higher than that of other spacer-containing membranes at similar IECs. The H 2 /O 2 single cell constructed with this membrane exhibits a good peak power density of 292 mW/cm2 at 60 °C. In addition, the steric hindrance of the extender gives rise to higher alkali stability of the AEM than that of the membrane which does not have the extender. Our work provides a meaningful direction of side chain design which can effectively improve conductivity and alkaline stability of AEMs. Image 1 • Alkoxy extender and alkyl spacer were co-introduced into anion exchange membrane. • Alkoxy extender and alkyl spacer can synergistically improve ion conductivity and chemical stability of membrane. • The highest conductivity of 87.3 mS/cm at 80 °C was obtained at a low IEC of 1.13 mmol/g. • The H 2 –O 2 fuel cell employing the above AEM yielded a power density of 292 mW/cm2 at 60 °C. [ABSTRACT FROM AUTHOR]

The anion exchange membranes (AEM) is one of the key components for alkaline electrolyte membrane fuel cells. However, poor alkaline stability and conductivity of the membrane greatly hinders its practical application. Herein, we report a novel 4-(dimethylamino)butyraldehyde diethyl acetal (DABDA) quaternized polysulfone AEM, or PSf-DABDA, which shows improved conductivity and alkaline stability due to the better hydrophilicity and the electron donating effect imparted by the long alkyl substituent with two ether-containing moieties in the cation structure. Its room temperature conductivity reaches 21 mS/cm while that of trimethylamine (TMA)- and dimethylbutylamine (DMBA) quaternized AEMs with comparable ion exchange capacity (IEC) is 11.8 and 13.2 mS/cm, respectively. When treated 150 h in 1 M NaOH at 60 °C, the PSf-DABDA membrane experiences a slight conductivity decrease of 5% while the PSf-TMA and PSf-DMBA membranes with a comparable IEC suffer a more serious conductivity decay of 19 and 13.5%, respectively. The better alkali stability of PSf-DABDA over its counterparts is further confirmed by a density functional theoretical study and a structural characterization before and after the alkali treatment. Our work demonstrates the advantage of the DABDA cation by both experimental and computational study; it presents a new possibility of improving AEM conductivity and stability. Image 1 • Anion exchange membranes with a novel cation containing long ether substituent were prepared. • The method was facile and more environmentally benign than some traditional ones. • The membrane showed an improved room temperature conductivity of 21 mS/cm. • 95% conductivity was retained after 150 h alkali treatment at 60 °C. • Advantage of the cation structure was confirmed by density functional theory. [ABSTRACT FROM AUTHOR]

Ethno-pharmacological relevance To best of our knowledge it is first quantitative ethno-botanical study from Alpine and Sub-alpine, Western Himalaya of Pakistan. The study aims to report, compare the uses and highlight the ethno-botanical significance of medicinal plants for treatment of various diseases. Methods A total of 290 (278 males and 12 females) informants including 14 Local Traditional Healers (LTHs) were interviewed. Information was collected using semi-structured interviews, analyzed and compared by quantitative ethno-botanical indices such as Informant Consensus Factor (ICF), Relative frequency of citation (RFC), use value (UV), Fidelity Level (FL) and Jaccard index (JI). Results A total of 125 plant species (Gymnosperms 7 species, Monocotyledons 2 and 116 Di-cotyledons) belonging to 41 families are collected, identified and ethno-botanically assessed. The most dominant family is Ranunculaceae (20 species) followed by Rosaceae (14 species). In diseases treated, gastrointestinal tract (GIT) diseases have highest proportion (27.5%) followed by respiratory diseases (20%) in the mountain communities. The most dominant life form of plants used is herbs (78%) followed by shrubs (19%) while the most commonly used plant parts are leaves (44 reports) followed by underground part, the roots (37 reports). The highest ICF (0.68) is found for ear, nose and eye disease category followed by respiratory disorders (0.46). There are 15 medicinal plants having 100% FL. Use value (UV) and Relative frequency of citation (RFC) range from 0.03 to 0.53 and 0.04 to 0.23 respectively. In comparison, maximum similarity index is found in the studies with JI 19.52 followed by 17.39. Similarity percentage of plant uses range from 1.69% to 19.52% while dissimilarity percentage varies from 0% to 20%. Conclusions The Alpine and Sub-alpine regions of Pakistan are rich in medicinal plants and still need more research exploration. On the other hand, ethno-botanical knowledge in study areas is decreasing day by day due to high emigration rates resulting from after effects of wars during the last few decades. Historically developed ethno-botanical heritage should be preserved and promoted on global level for analyzing phytochemical, pharmaceutical and other biological activities for future drug discovery. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Malaria is among the most prevalent infectious diseases in the developing countries of world. Estimated number of annual malaria episodes in Pakistan is 1.5 million, but very little is known about medicinal plant species of Pakistan, which have great potential against malarial disease. Present study was aimed to document medicinal plant species used by the local inhabitants of Lesser Himalayas-Pakistan to treat malaria. Materials and methods Data were collected through interviews, questionnaires and contributor observation. A total of 55 informants aged between 25 and 80 years who were familiar with malarial disease participated in the survey. Results A total of 84 plant species belonging to 69 genera and 50 families were recorded to treat malaria. Asteraceae was found as most cited botanical family with (11.9%) representation, followed by Lamiaceae (5.9%), Solanaceae and Verbenaceae (4.7%) and Violaceae (3.5%) respectively. About 60% of the inhabitants prefer herbal treatment by local herbalists or self-treatment with locally available medicinal plant species. Of the plants identified during present investigation against malaria, Azadirachta indica, Swertia chirayita and Swertia ciliata exhibited uppermost frequency of encounter (36.3%) and corresponding PR value 5. About 67.2% of the botanical taxa are reported for the first time in the treatment of malaria. It was observed thatover harvesting is the foremost threat to medicinal plant species of the study area. Conclusion Present survey indicates that traditional knowledge about the use of plant species against various diseases and particularly to treat malaria is in decline. Similarly anthropogenic pressure, over exploitation and grazing of the botanical taxa are the major concerns regarding medicinal plant biodiversity loss. Frequently utilized plant species with significant malarial reduction should be authenticated by in vitro and in vivo standard tests [ABSTRACT FROM AUTHOR]

Abstract: Aim of the study: Pregnane glycosides are potent cytotoxic agents which may represent new leads in the development of anti-tumour drugs, particularly in the treatment of breast cancer, because of the structural similarity to estrogenic agonists. Caralluma species are natural sources of a wide variety of pregnane glycosides. The aim of the study was to isolate, using an activity-guided fractionation approach, novel pregnane glycosides for testing on breast cancer and other tumour lines. Materials and methods: The effect of crude extracts, specific organic fractions and isolated compounds from Caralluma tuberculata was tested on the growth and viability of MCF-7 estrogen-dependent, and MDA-MB-468 estrogen-independent breast cancer cells, Caco-2 human colonic cells, HUVECs and U937 cells. Neutral red uptake and MTT assays were used. Apoptosis was detected by Western blot of poly-(ADP ribose) polymerase (PARP) as were other markers of nuclear fragmentation (DNA ladder assay, staining of cells with nuclear dye DAPI). The involvement of caspases was investigated using the pan-caspase inhibitor Z-VAD-FMK. Results: The ethyl acetate fraction of Caralluma tuberculata was found to be the most potent anti-proliferative fraction against all three cancer cell lines. Two novel steroidal glycosides were isolated from the active fraction after a series of chromatographic experiments. The structure of the isolated compounds was elucidated solely based on 2D-NMR (HMBC, HETCOR, DQF-COSY) and MS spectral analysis as compound 1: 12-O-benzoyl-20-O-acetyl-3β,12β,14β,20β-tetrahydroxy-pregnan-3-ylO-β-D-glucopyranosyl-(1→4)-β-d-glucopyranosyl-(1→4)-3-methoxy-β-d-ribopyranoside, and as compound 2: 7-O-acetyl-12-O-benzoyl-3β,7β,12β,14β-tetrahydroxy-17β-(3-methylbutyl-O-acetyl-1-yl)-androstan-3-ylO-β-d-glucopyranosyl-(1→4)-6-deoxy-β-d-allopyranosyl-(1→4)-β-d-cymaropyranosyl-(1→4)-β-d-cymapyranosyl-(1→4)-β-d-cymaropyranoside. Compound 1 (pregnane glycoside) and compound 2 (androstan glycoside) induced apoptosis at <25μM after 48h as assessed by cell shrinkage, PARP cleavage, DNA fragmentation, and reversal with the caspase inhibitor. Conclusions: Two novel steroid glycosides isolated from Caralluma tuberculata possess moderate, micromolar cytotoxic activity on breast cancer and other cells in vitro, which may indicate a source of activity in vivo of interest to future drug design. [Copyright &y& Elsevier]

Renal transplantation in developing countries. Healthcare in developing countries less funded than developed nations (0.8 to 4% vs. 10 to 15%, respectively), and must contend against ∼1/3 of the population living below the poverty line ($1US/day), poor literacy (58% males/29% females), and less access to potable water and basic sanitation. Cultural and societal constraints combine with these economic obstacles to translate into poor transplantation activity. Donor shortage is a universal problem. Paid donation comprises 50% of all transplants in Pakistan. Post-transplant infections are a major problem in developing countries, with 15% developing tuberculosis, 30% cytomegalovirus, and nearly 50% bacterial infections. The solutions to these problems may seem simplistic: alleviate poverty, educate the general population, and expand the transplant programs in public sector hospitals where commerce is less likely to play a major role. The SIUT model of funding in a community-government partnership has increased the number of transplantations and patient and organ survival substantially. Over the last 15 years, it has operated by complete financial transparency, public audit and accountability. The scheme has proven effective and currently 110 transplants/year are performed, with free after care and immunosuppressive drugs. Confidence has been built in the community, with strong donations of money, equipment and medicines. We believe this model could be sustained in other developing nations. [ABSTRACT FROM AUTHOR]

Since the discovery of Deoxyribonucleic acid (DNA) capability in forensic investigation, it has been an important part of the criminal justice system. In most criminal cases DNA profile originating from evidence sample collected from the crime scene is compared with the DNA profile from the reference sample. However, when a reference sample is not available for comparison, familial DNA analysis can provide important investigation leads in a criminal investigation process by identifying an individual. Moreover, this analysis is also proving effective in the identification of ethnicity and ancestry of an individual. A number of different methodologies and software are being used for familial DNA analysis. This review describes the importance of familial DNA analysis, methodologies used for familial DNA searching and identification, and its advantages in forensic. Moreover, ethical, legal and social issues associated with familial DNA analysis have also been discussed along with future directions for the proper implementation of this technology. [ABSTRACT FROM AUTHOR]