Population dynamics of an invasive species Carassius auratus in the Shatt Al-Arab River, Iraq

The population dynamics of the crucian carp, Carassius auratus in the Shatt Al-Arab River, Iraq was studied from November 2015 to October 2016 with monthly samples collected by different fishing gears. The FAO-ICLARM Stock Assessment Tool (FiSAT II) software was used for the mathematical analysis. Length-weight relationship was calculated as W= 0.0149L3.065 for fish length 4.6 to 26.8 cm. Growth parameters L∞, K and Ø were computed as 29.1 cm, 0.51 and 2.635. The total (Z), natural (M) and fishing (F) mortalities were 2.69, 1.09 and 1.60, respectively. Exploitation rate (E) was 0.59. Length at first capture (Lc) was found to be 10.04 cm. C. auratus displayed one main pulse of annual recruitment. The relative yield per recruit analysis revealed that the exploitation rate (E) of C. auratus was higher than the biological target reference points E0.1 and equivalent to Emax. It could be concluded that the C. auratus stock in the Shatt Al-Arab River is operating nearby the exploited situation and needs some precautionary measures to avoid the overexploitation by activating the national law of fishing, exploiting and protecting aquatic resources, in particular preventing illegal fishing methods and follow up the execution of the closed season to prevent the decline of our fish resources

Population dynamics and management of two cichlid species in the Shatt Al-Arab River, Iraq

Cichlids are invasive fish to Iraqi waters and became well established and prevailing in different waters. Despite that, there is no stock assessment study conducted for these fish. So, growth, mortality, recruitment and yield-per-recruit of two cichlid’s species; Coptodon zillii and Oreochromis aureus from the Shatt Al-Arab River, Iraq were evaluated from November 2015 to October 2016 using the FiSAT software. A total of 1285 C. zillii (2.9-24.0 cm TL) and 1353 O. aureus (4.5-25.0 cm TL) were examined. Length-weight relationships were derived, indicating allometric growth for both species. The growth parameters (L?, K, Rn, to and ?) obtained for C. zillii were 25.5 cm, 0.320, 0.212, -0.793 and 2.318, respectively, while for O. aureus were 27.8, 0.490, 0.214, -0.271 and 2.578, respectively. The annual rate of total mortality (Z), fishing (F) and natural (M) for C. zillii was found to be 1.51, 0.84 and 0.68 respectively, and for O. aureus 2.49, 1.08 and 1.41, respectively. The present exploitation rates (Epresent) for C. zillii and O. aureus were computed to be 0.454 and 0.57, respectively. Lengths at first capture (LC) were 12.97 cm for C. zillii and 13.25 cm for O. aureus. The peaks of recruitment of C. zillii and O. aureus were from February to May and May to July, respectively. The Epresent for C. zillii and O. aureus were below the biological target reference points (F0.1  and Fmax), indicating that these species were not overexploited. For management purposes, more yields could be obtained by an increase in the fishing activities on cichlids

Evaluation of the inland fisheries in Basrah province in Iraq during 2020-2021

The study was aimed to update the knowledge on the fish landings of the inland fisheries in Basrah province, Iraq. The species composition, species and total landings, and their trends in six landing sites throughout the study region were evaluated during the year 2020-2021. Species compositions were included seven cyprinids’ species, three cichlids’ species, three mullet’s species, and two species from sparids and silurids. The exotic species, C. carpio, tilapias species and C. auratus dominated the landings constituting 44.2% of the total catch, whereas the highly valued native species (M. sharpeyi, L. xanthopterus, C. luteus and A. grypus) forming only 12.4% of the total catch. The total landing reached 2,427.78 t in 2020 and 2,365.15 t in 2021, and these values were higher than what was recorded during the past years since the year 2009. This is due to the prevalence of aliened species and the increase in the fishing effort, such as the numbers of fishermen and fishing boats. Therefore, in fisheries management point of view, it is essential to enhance the stocks of the native species, minimize the dispersal and impacts of some exotic species, and activate the national regulating fishing, exploitation and protection of aquatic organisms to improve the inland fisheries

Mechanical Properties of TiO2 Reinforced Polystyrene- Modified Unsaturated Polyester

The aim of current research is carrying out some modifications on the properties of resin material Unsaturated Polyester (UP) by adding thermoplastic material Polystyrene (PS) in different weight ratios included 4%, 8%, 12%,14%,16%,20% and 24% was used to prepare binary polymer blend. The best ratio was selected in terms of the homogeneity case between the two polymers and according to compression strength for all prepared specimens. The ratio 92/8 wt.% of UP/PS blend was selected and reinforced with different particle volume fractions of 1%, 3%, 5% and 7% using of TiO2 particles. The composite materials with unsaturated polyester-polystyrene matrix properties were evaluated by conducting the mechanical tests which included compression, hardness and impact resistance. Results of compression test showed that the compression strength decreases as polystyrene percentage (PS) increases. While the TiO2 an addition has helped in balancing the original compression strength reduction up to 3% vol. of TiO2 and then the strength decreases. The results confirmed that the best enhancement is of 3% vol. of TiO2 considering compression strength and impact. The SEM results indicate that the polystyrene particles have good distribution through UP, this distribution of smaller particles is responsible for lower crack growth. The SEM results of composites specimen show the TiO2 particles have good distribution through the matrix up to 3% vol., the mechanical properties beyond 3% vol. decreased due to the presence of particle agglomerations. Keywords: Unsaturated polyester, Polystyrene, Mechanical properties, SEM

Mechanical Properties of Carbon/Polypropylene Fiber Reinforced Rubber-Modified Epoxy System

Epoxies as a thermoset polymer have gained a considerable attention in structural, electrical, and marine applications. To widen their usage and overcome their brittleness, many polymers were blended with it. The addition of Polysulfide rubber helps in increasing the impact resistance of Epoxy, while in the other hand; it reduces strength , modulus, hardness and creep resistance. That leads to the need for another material to compensate the reduction in these properties. Carbon, polypropylene as an inorganic and polymeric short fibers with their exceptional and different mechanical properties will compensate many drawbacks of polysulfide addition in enhancing mechanical properties. The composite material with Epoxy-Polysulfide matrix properties were evaluated by conducting the mechanical tests which include compression test, hardness test, impact resistance test. The fracture surface of composite impact specimens was observed by Scanning Electron Microscopy SEM on all designed experimental samples. Elongation and impact strength of epoxy- polysulfide blend were found to increase with increasing rubber content while compressive strength and modulus decrease. The influence of fiber adding on the mechanical properties of the composite was studied , the mechanical properties of the blend matrix were found to be better than those of the pure epoxy. The morphology of the fractured surfaces showed significant signs of plastic deformation such as shear bands, high deformation, and cavitations due to rubber addition, and this correlates well with mechanical properties which resulted in an increase in toughness of the composites when rubber content was increased. The results of this investigation clearly show the possibility of balancing strength and toughness of the material when adding rubber, fiber to epoxy. Results of compression test showed that the compressive strength decreases as Polysulfide percentage (PS) increase. While the carbon fiber addition helped in balance or overcomes the original compressive strength reduction up to 30 vol.%. of fiber. The results confirmed that the best modification is the addition of 6% polysulfide considering compressive strength, Impact and hardness. While 20% carbon fiber and 30% Polypropylene fiber gives the optimum mechanical properties in compression and Impact, respectively, for the composite samples. Keywords: Epoxy resin, Liquid rubber, Mechanical properties

The Product of Finite Numbers of Automorphic Composition Operators on Hardy Space H2

Throughout this paper we study the properties of the composition operator.........

Effect of Molarity on the structural and optical properties of ZnO thin films deposit by CSP

ABSTRACT ZnO thin films have been prepared by chemical spray pyrolysis technique CSP). XRD pattern reveals that the preferred orientation was varied with concentration, topography analysis was done by AFM micrograph which confirm the existence of nonstructural films. The optical properties was done by recorded the transmittane and absorbance which were affected by an increase in concentration. The values of optical energy gap obtained from Tauc relation were 3.17, 3.18 and 3.19 eV for 0.05, 0.1 and 0.5 M respectively. Urbach energy confirms the decrease in band tail as the concentration increase

Understanding settlement services literacy and the provision of settlement services for humanitarian migrants in Australia : a service provider perspective

Over the past 40 years, successive Australian Governments have developed a comprehensive programme of settlement services (SS) designed to improve settlement outcomes for humanitarian migrants. Many humanitarian migrants do not arrive with the appropriate skills and abilities to fully benefit from available SS. “Settlement services literacy” (SSL) has been proposed as a framework to contextualise factors that may enable or constrain humanitarian migrants' utilisation of SS. The aim of this study was to investigate the provision of SS in relation to SSL, that is humanitarian migrants' ability to effectively access information and services, to critically assess services, and to politically mobilise and effect change. Qualitative interviews were conducted with 26 service providers representing 19 organisations in Greater Western Sydney (n = 8) and Melbourne (n = 11). The study found that SS programmes address many of the indicators that promote SSL acquisition. However, this is not achieved systematically, nor do the programmes reflect all indicators across the three SSL levels. This study provides new insights into various factors impacting the effectiveness of SS provision and SSL acquisition. These insights can inform future programme policy reforms and contribute to more effective and responsive service systems that meet the diverse and complex needs of humanitarian migrants

Establishing the psychometric properties of constructs from the conceptual 'settlement services literacy' framework and their relationship with migrants' acculturative stress in Australia

Background: Effective migration often requires supports for new arrivals, referred to as settlement services. Settlement services literacy (SSL) is key to ensuring new migrants have the capability to access and utilise the information and services designed to support the resettlement process and achieve positive settlement outcomes. To date, however, no research has sought to empirically validate measures of SSL or to assess individual migrants' levels of SSL. The aim of this study was to establish the psychometric properties of constructs from the conceptual SSL framework. Design Using a snowball sampling approach, trained multilingual research assistants collected data on 653 participants. The total sample was randomly divided into two split-half samples: one for the exploratory factor analysis (EFA; N = 324) and the other for the confirmatory factor analysis (CFA; N = 329) and scale validation. The final SSL scale included 30 questions. The full data set was used to test the nomological validity of the scale regarding whether the components of SSL impact on migrants' level of acculturative stress. Results: The EFA yielded five factors: knowledge (eight items, α = 0.88), empowerment (five items, α = 0.89), competence (four items, α = 0.86), community influence (four items, α = 0.82), and political (two items, α = 0.81). In the CFA, the initial model demonstrated a poor to marginal fit model. Its re-specification by examining modification indices resulted in a good model fit: CMIN/DF = 3.07, comparative fit index = 0.92, root mean square error of approximation = 0.08 and standardised root mean square residual = 0.07, which are consistent with recommendations. All the path coefficients between the second-order construct (SSL) and its five dimensions (knowledge, empowerment, competence, community influence and political) were significant at an α = .05 level, giving evidence for the validity of different SSL dimensions. We found that SSL is significantly related to migrants' acculturative stress (β = - 0.39, p < 0.05) in the nomological model. Conclusions The study provides evidence of the construct validity and reliability of the SSL tool. It provides the basis for integrating the measures of SSL into evaluation of settlement services. This will allow for more effective decision-making in designing and implementing settlement services as well as funding and service agreements to address any deficiencies

Overview On Surgical Management Of Overactive Bladder

Overactive bladder syndrome is a persistent and incapacitating disorder that has profound medical, psychological, and social implications, greatly impacting the wellbeing of countless individuals globally. A significant number of individuals experience urine urgency, which can be extremely bothersome. The primary indicator of overactive bladder (OAB) is a sense of urgency, often accompanied by increased urine frequency and nocturia. After ruling out other medical conditions with similar symptoms, the initial approach to managing OAB is providing guidance on fluid consumption and bladder training. If needed, antimuscarinic medicines may be added as a supplement. If patients have significant distress from OAB symptoms even after maximizing medicinal treatment, they may choose to undergo invasive procedures. There is currently a limited understanding of the hierarchical structure of central nervous system control. However, the use of functional imaging is starting to reveal the difficulties that need to be addressed in this area. Current research is exploring the use of botulinum neurotoxin-A injection, oral β3-adrenergic agonists, and innovative methods for nerve stimulation as potential therapies. The inherent subjectivity of urine urgency, the absence of animal models, and the complex pathophysiology of overactive bladder (OAB) pose substantial obstacles to achieving effective clinical therapy