24 research outputs found

    Perturbation method for linear and non-linear fractional order systems and integral representation for evaluation of integrals

    Get PDF
    In the present work, the authors used the Laplace transform - perturbation method to solve certain linear and non-linear systems of fractional differential and difference equations with constant coefficients with the fractional derivatives in the Caputo sense. We also considered the problems of string vibrations in different cases with fractional damping. Another purpose of this article is to evaluate certain integrals. Illustrative examples are also provided

    An integrative perspective on the interplay between early maladaptive schemas and mental health: The role of self-compassion and emotion regulation

    Get PDF
    Objectives We aimed to test whether negative emotion regulation difficulties and self-compassion mediate the relationship between early maladaptive schemas (EMSs) and symptoms of psychopathology and life satisfaction. Methods Data were collected from 296 adults (179 females, 117 males), whose age ranged from 17 to 52 years. The mediating roles of self-compassion and negative emotion regulation were examined via Hayes' procedure (PROCESS) for multiple mediation. Results Negative emotion regulation was the only mediator to psychopathological symptoms, with no additional role for self-compassion, whereas self-compassion mediated only to life satisfaction, with no additional role for negative emotion regulation. Conclusions The results provide evidence for unique mediating roles of negative emotion regulation and self-compassion, depending on the outcome variable. That helps to understand how problems that may be identified in terms of positive and negative domains are related to EMSs, and allows to put forward potential strategies within the frame of schema therapy

    Study on macrobenthic communities in the range of fish cage-culture area (before breeding) in the southern Caspian Sea (Mazandaran coast-Kelarabad)

    Get PDF
    The abundance and biomass of benthic macroinvertebrates were studied in the place of fish cage culture in southern coasts of Caspian sea (Mazandaran waters- kelarabad). The goal of this study was to consider of fish cage culture effects on the abundance and biomass of benthic macroinvertebrates. The sampling was carried out in 3 stations in depth of 20 meter of Kelarabad waters monthly. In this study 7 species were identified belonged to 5 genus of 4 family. Totally 23442 sample of benthic invertebrates were counted that the lowest and highest abundance were in station 1(23.4%) and station 2(46.8%) respectively. The results of stations study showed that the highest abundance and biomass were in stations 2 and 3 with the average of 646 ± 1230.4 n/m^2 and 0.526 ± 1.001 gr/m^2 respectively. This coulld be respectively dependant to not settling of cage (witness station) and appearance of Cerastoderma glaucum because of its large body in station 1. The difference of abundance and biomass between different stations was not significant (p ›0.05). The study on abundance and biomass in different seasons showed that the highest abundance in autumn with the avarage of 888.13 ± 1371.58 n/m^2 belonged to Strblospio gynobranchiata and the highest biomass belonged to C. glaucum which was because of appearance of not native species of polychaeta and also the species with shell covering from bivalvia. The results showed that the specie of S. gynobranchiata from polychaeta including 93.3% of abundance was the dominant specie that could be related to appropriate ecological conditions for living and high adaptability. It was concluded that the abundance and biomass of benthic macroinvertebrates in station 1 was lower than other stations which was related to fish cage culture activity and its effects on benthic macroinvertebrates. So it is suggested that each mariculture activity in southern coasts of Caspian Sea should be carried out with regarding to environmental considerations and performance of comparative evaluation project of environmental effects

    Study on physic-chemical parameters of waters for fish cage culture site selection in the southern of Caspian Sea

    Get PDF
    Marine aquacultures growth require good quality water is leading to high efficiency and low risk to human health. In other words, the water quality is a critical factor to success and failure of the aquaculture industry. The aim of this project is to study water quality and the trophic status at the different depths and layers in the southern Caspian Sea based on environmental parameters and nutrients during three periods (2008, 2009 and 2010-2011) in order the feasibility of fish cage. Results showed that water temperature, transparency, pH, dissolved oxygen were varied 5.50-32.60 ̊C, 3.50- 10.00 m, 7.15-8.80 and 3.18-12.00 mg/l at the different depths and layers, respectively. In addition, The values of NH4^+, NH3, NO^2-, NO3^- and PO4^-3 were 0.001-0.140 mg/l, 0.01-22.63 µg/l, 0.1-21.2 µg/l, 0.001-0.423 mg/l and 0.008-0.071 mg/l, respectively. Inorganic nitrogen (DIN/N), inorganic phosphorous (DIP/P) and total phosphorous (TP) were registerd 0.68-14.75, 0.07-0.68 and 0.01-2.67 µM, respectively. Thermal startification are more important for fish-breeding. Thermal stratification was occurred from depths greater than 20 m in late spring to early fall in the Caspian Sea. Optimum transparency for fish farming cage was considered less than 5 meter which in this study were recorded from 20 to 50 meter depths. The range of the standard of pH and dissolved oxygen for fish farming cage were 7.80-8.50 and >5 mg /l that in current study results of pH and dissolved oxygen were consistent.Various forms of nitrogen (ammonium, nitrite and nitrate ) at the different layers were acceptable and less than the threshold limit of Australia and New Zealand. But, phosphate value was more than threshold limit of Australia and New Zealand at some layers depth during years of 2009 and 2010- 2011. The results of the nutrients compared with data from the reference year (1996-1996 ) in the Caspian Sea was shown that this ecosystem passed oligotrophic status and shifted to mezotrophic and eutrophic condition. In addition, the values of NH4/N, NO3/N and DIP/P compared with eutrophic condition of reference year (2005) showed that Caspian ecosystem was not passed euotrophic condition and it still under mezotrophic status. As a conclusion, it seems that offshore of the Caspian Sea (depths between 20 to 50 meter) were suitable for different species of fish for cage culture. But, since 2000 decayds the Caspian Sea has experienced four times algal bloom (toxic and harmful species) and in recent years a number of other species also has reached to bloom potential and also mezotrophic condition of this ecosystem, it is appropriate that the establishment of fish farming cages carried out as a pilot to more precautionary approach which not lead to environmental disaster

    Integral transform method for solving time fractional systems and fractional heat equation

    No full text
    In the present paper, time fractional partial differential equation is considered, where the fractional derivative is defined in the Caputo sense. Laplace transform method has been applied to obtain an exact solution. The authors solved certain homogeneous and nonhomogeneous time fractional heat equations using integral transform. Transform method is a powerful tool for solving fractional singular Integro - differential equations and PDEs. The result reveals that the transform method is very convenient and effective

    Doppler sonography enhances rtPA-induced fibrinolysis in an in vitro clot model of spontaneous intracerebral hemorrhages.

    No full text
    BackgroundTranscranial Doppler (TCD) was shown to enhance intravascular fibrinolysis by rtPA in ischemic stroke. Studies revealed that catheter-based administration of rtPA induces lysis of intracerebral hemorrhages (ICH). However, it is unknown whether TCD would be suitable to enhance rtPA-induced fibrinolysis in patients with ICH. The aim of this study was to assess the potential of TCD to enhance rtPA-induced fibrinolysis in an in vitro clot system.MethodsReproducible human blood clots of 25 ml were incubated in a water bath at 37°C during treatments. They were weighed before and after 6 different treatments: (I) control (incubation only), (II) rtPA only, (III) one Doppler probe, (IV) two Doppler probes placed vis-à-vis, (V) one probe and rtPA and (VI) two probes and rtPA. To quantify lysis of the blood clots and attenuation of the Doppler through a temporal squama acoustic peak rarefaction pressure (APRP) was measured in the field of the probes. Temperature was assessed to evaluate possible side effects.ResultsClot weight was reduced in all groups. The control group had the highest relative end weight of 70.2%±7.2% compared to all other groups (pConclusionsTCD significantly enhances rtPA-induced lysis of blood clots, and the effect is amplified by using multiple probes. Our results indicate that bitemporal TCD insonation of hematomas could be a new and safe approach to enhance fibrinolysis of ICH´s treated with intralesional catheter and rtPA

    Energy-efficient method for developing in-situ Al-Cu metal matrix composites using microwave sintering and friction stir processing

    No full text
    The problems associated with the fabrication of in situ metal matrix composites (MMC) by conventional methods can be avoided by using microwave sintering and friction stirring in combination. The current study investigates the mechanical and electrical properties of pure aluminum (Al-100 wt%) and Al-Cu MMC. The results showed that excellent ultimate tensile strength, toughness, and electrical conductivity can be acquired simultaneously. The obtained ultimate tensile strength in the case of Al-100wt% (184.5 MPa) has improved two-fold than that of a typical commercially pure aluminum AA1016 (90 MPa). Similarly, the electrical conductivity of developed pure aluminum (88.87% IACS) is 1.4 times higher compared to AA1016 alloy (62% IACS). For Al-Cu MMC the copper is added in steps of 5 wt% (5%, 10%, 15%, and 20%). The maximum ultimate tensile strength (205.2 MPa) and the electrical conductivity (71.53% IACS) obtained for Al-10wt%Cu are higher compared to the AA1016 alloy. The present investigation suggests a novel processing route and opens up new research avenues in the field of solid-state materials processing

    Combination of ultrasound and rtPA enhances fibrinolysis in an <i>In Vitro</i> clot system

    No full text
    <div><p>Background</p><p>Catheter-based lysis with recombinant tissue plasminogen activator (rtPA) is a well-established therapy for spontaneous intracerebral hemorrhage (ICH). The effectiveness of this therapy can be increased with ultrasound, but the optimal conditions are not yet clearly established. Using a novel in vitro system of blood clots previously developed by our group, we investigated various parameters of intralesional sonothrombolysis using an endosonography catheter in combination with rtPA.</p><p>Methods</p><p>Standardized human blood clots were equipped with a drainage catheter and weighed before and after 4 treatments: control (drainage only), rtPA only, ultrasound only and the combination of rtPA+ultrasound. The effectiveness of ultrasound was further analysed in terms of optimal frequency, duration and distance to the probe. Temperature and acoustic peak rarefaction pressure (APRP) were assessed to analyse potential adverse effects and quantify lysis. Histo-morphological analysis of the treated clots was performed by H&E staining and confocal laser scanning microscopy using fluorescent fibrinogen.</p><p>Results</p><p>The combined treatment rtPA+ultrasound achieved the highest lysis rates with a relative weight of 30.3%±5.5% (p<b>≤</b>0.0001) compared to all other groups. Similar results were observed when treating aged clots. Confocal fluorescent microscopy of the treated clots revealed a rarefied fibrin mesh without cavitations. No relevant temperature increase occurred (0.53±0.75°C). The optimal insonation treatment time was 1 hour. APRP measurements showed a lysis threshold of 515.5±113.4 kPa. Application of 10 MHz achieved optimal lysis and lysis radius, while simultaneously proving to be the best frequency for morphologic imaging of the clot and surrounding tissue.</p><p>Conclusions</p><p>These promising data provide the basis for an individualized minimal invasive ICH therapy by rtPA and sonothrombolysis independent of ICH age.</p></div
    corecore