332 research outputs found

    Enumeration and Asymptotic Formulas for Rectangular Partitions of the Hypercube

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    We study a two-parameter generalization of the Catalan numbers: Cd,p(n)C_{d,p}(n) is the number of ways to subdivide the dd-dimensional hypercube into nn rectangular blocks using orthogonal partitions of fixed arity pp. Bremner \& Dotsenko introduced Cd,p(n)C_{d,p}(n) in their work on Boardman--Vogt tensor products of operads; they used homological algebra to prove a recursive formula and a functional equation. We express Cd,p(n)C_{d,p}(n) as simple finite sums, and determine their growth rate and asymptotic behaviour. We give an elementary proof of the functional equation, using a bijection between hypercube decompositions and a family of full pp-ary trees. Our results generalize the well-known correspondence between Catalan numbers and full binary trees

    Effect of hypoxia, normoxia and hyperoxia conditions on gill histopathology in two weight groups of beluga (Huso huso)

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    The influence of dissolved oxygen concentration on gill histopathology of great sturgeon (Huso huso) was evaluated in two weight classes (initial weight 280.9±49.2 g and 1217.9±138.1 g respectively). Oxygen treatments included hypoxia (2-3 mg/l), normoxia (5-6 mg/l) and hyperoxia (9-10 mg/l). The fish were acclimated to experimental tanks for one week then randomly distributed into 9 tanks in each of the initial weight classes (3 and 6 fish per tank in higher and lower initial weight classes respectively) for 8 weeks. In order to find the histopathological changes, gill samples were collected, dehydrated through ethanol series, embedded in paraffin , sectioned at 7 µm thickness using a Leitz microtome and stained with H & E. No mortality was observed over the 8 weeks of the experimental period. There were significant differences in weight and feed intake between treatments in the both weight classes (P<0.05). Fork length showed significant differences in lower initial weight class (P<0.05). The main histopathological changes were observed in gills including: Hyperplasia, loss of secondary lamellae, hemorrhage and congestion in primary and secondary lamellae, lamellar fusion, epithelial lifting in secondary lamellae, clubbing of secondary lamellae, telangiectases, increase in melanin pigments and numerous vacuoles in primary and secondary lamellae (in hyperoxia treatment). All these lesions may reduce gill functional surface of gaseous exchange, impairing respiratory function

    Fish and shrimp waste management at household and market in Bushehr, Iran

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    Abstract: The aim of this study was to investigate the estimation and management of fish and shrimp wastes in Bushehr province. Two-part questionnaire including the demographic information, and fish and shrimp waste disposal method were completed for 91 stores and 636 households. The quantity of generated wastes was estimated based on the 3 different Scenarios. In addition, the waste generation factor were calculated for common fish and shrimp species. Results showed the waste generation factor for fish and shrimp equal to 32.67 and 42%, respectively. The total quantity of fish- and shrimp-generated wastes in Bushehr province was estimated to be 29,388 tons per year, of which the quantity of generated waste by stores and by households was 3731 tons per year (16 ton per capita per year) and 8804 tons per year (34 kg per capita per year), respectively. The remaining quantity is related to other unaccounted sectors such as fish industries. Moreover, the biogas production potential from an anaerobic digestion were estimated 2,675,400 m3 per year, which is equivalent to 16,052 MWh. In addition, the biodiesel production potential was obtained equivalent to 19 kt, which is about 4.2% of the total diesel fuel requirement of the province in 2016. Graphic abstract: [Figure not available: see fulltext.

    U–Pb zircon geochronology, petrochemical and Sr–Nd isotopic characteristic of Late Neoproterozoic granitoids of the Bornaward complex (Bardaskan-NE Iran)

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    The Bornaward granitoids in the Taknar zone are located in the northeast of the central Iranian block in northeast Iran (Khorasan Razavi province), about 280 km southwest of Mashhad city and 28 km northwest of Bardaskan city. Taknar zone is an exotic block, bordered by two major faults, the Great Kavir fault in the south and Rivash fault in the north. Intrusive rocks of the study area, called the Bornaward granitoid complex (BGC), include of granite, alkali granite, syenogranite, leucogranite, granophyre, monzogranite, granodiorite, tonalite, diorite and gabbro intruded into the center of Taknar zone. These intrusive rocks affected low grade metamorphism. The results of U-Pb zircon dating on two granite samples, one belonging to the Taknar mine west of the study area and the other the Bornaward granitoids in the eastern part of study area, and also one granodiorite the Taknar mine area and one diorite the Bornaward area, yield ages of the granites as 540.5±2.9 Ma (Taknar mine area) and 550.41 3.21,-4.54 Ma (Bornaward area), the granodiorite as 550±6.9 Ma and diorite as 551.96±4.32 Ma, all Late Neoproterozoic. The Bornaward intrusive bodies are classified as belonging to the ilmenite-series of reduced granitoids. Some small high magnetite-granite and tonalite outcrops in the study area are classified as belonging to the magnetite-series of oxidized granitoids. Chemically, most granitoids of the study area are S-type middle-high metaluminous to slightlymiddle peraluminous and belong to tholeiite, calc-alkaline to high-K calc-alkaline rock series with enrichments in LIL (Cs, Rb and Ba, U, K, Zr, Y, Th) elements and depletion in HIL (Sr and Nb, Ta, Ti) elements. Chondrite-normalized Rare Earth Elements (REEs) plots indicate minor enrichments of LREEs in comparison with HREEs, with (La/Yb)N between 1.04 -7.90 and total of REEs of the samples between 44.8 ppm (minimum) and 293.5 ppm (maximum) with strong negative anomaly of Eu compared to other Rare Earth elements. The Bornaward granitoid have an initial 87Sr/86Sr and 143Nd/144Nd ranging 0.703514 to 0.716888 and 0.511585 to 0.512061, respectively, when recalculated to an age of 550 to 538 Ma, consistent with the new radiometric age results. Initial εNd isotope values for granite, granodiorite and diorite range -6.73 to 2.52. TDM age of the BGC is 1.08-1.70 Ga. This indicates that the Bornaward granitoid complex (BGC) derived partial melting of distinct basement source regions with very high initial 87Sr/86Sr and underwent extensive crustal contamination

    The Actor–Partner Effects of Parenting Stress on Quality of Life Among Parents of Children with ASD: The Mediating Role of Mental Quality of Life

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    The present study investigated the actor–partner effects of parenting stress (PS) on quality of life (QoL) among parents (96 couples) of children with autism spectrum disorder (ASD). Data were collected using the QoL Scale and the PS Index. Structural equation modeling was also utilized to test the hypothesis. The results revealed the effects of PS in each parent on mental QoL of that parent. Maternal PS further shaped physical QoL in mothers. However, PS in one parent did not influence QoL of his or her partner. Accordingly, mental QoL had a mediating role between PS and physical QoL. It was ultimately suggested to take account of QoL among parents in addition to the treatment of children with ASD

    Effect of Mindfulness-Based Stress Reduction Training on Revealing Sexual Function in Iranian Women with Breast Cancer

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    Most studies on the treatment of sexual problems in women with breast cancer have been conducted based on a quantitative approach. Adding a post-intervention qualitative study can help to clarify the impact of the therapy on sexual function. The present mixed-method study was performed to determine the impact of mindfulness based stress reduction on sexual function in women with breast cancer. This study consisted of two quantitative and qualitative phases. The quantitative phase was a randomized clinical trial, where 52 subjects were randomly assigned to intervention and control groups that completed female sexual function index (FSFI) in pretest, posttest (after the intervention), and follow-up (1 month after the intervention) stages. Intervention was an eight-session group mindfulness-based stress reduction. After analyzing data from 46 subjects, qualitative data were collected using the conventional content analysis method. At the follow-up stage, statistically significant improvements were noted in the intervention group for the sexual desire (P = 0.021) and arousal (P = 0.021), but decreases were observed in orgasm scores (P = 0.042). In the control group, overall FSFI score decreased at follow-up compared to those of the pretest and posttest (P < 0.001. (There were no differences between the two groups in the three stages. Two main categories of qualitative analysis, i.e. “mindfulness, an attempt for love continuation” and “Sexual Responsiveness scope”, confirmed the results of quantitative phase. Based on the results, mindfulness intervention can impact the aspects of sexual performance that rely on women, which are mostly of psychological origin and may not affect all aspects

    Assessing the Mediating Role of Depression in the Relationship Between Feeling of Loneliness and Social Functioning in the Elderly [بررسی نقش میانجی افسردگی در ارتباط بین احساس تنهایی با عملکرد اجتماعی سالمندان شهر بوشهر]

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    Objectives Due to the rapid growth of the elderly population, it is very important to pay attention to their mental health indicators including feeling of loneliness, social functions and depression. This study aims to determine the mediating role of depression in the relationship between feeling of loneliness and social functioning in the elderly. Methods & Materials In this correlational cross-sectional study, 318 older adults covered by the comprehensive health centers in Bushehr, south of Iran in 2018 were selected using a simple random sampling method. To collect data, Russell’s UCLA loneliness scale (version 3), and Goldberg’s general health questionnaire (Depression and social dysfunction subscales) were used. We applied the partial least squaresstructural equation modeling to analyze the data in PLS Graph version 3.00 software. The significance level was set at 0.05. Results The mean age of the participants was 66.74±5.87 years; 55.3% were male and the rest were female. The results showed that feeling of loneliness directly (β=0.199, P<0.01) and through mediation by depression (β=0.183, P<0.001) could cause social dysfunction. Felling of loneliness and depression together explained 20% of the variance in social dysfunction. The outer and inner model fit indices indicated the models’ good fit. Conclusion Feeling of loneliness directly or by causing depression can reduce the social functioning of the elderly. The results of this study can be used in designing effective interventions to increase the social functioning of the elderly © 2022, Iranian Journal of Ageing.All Rights Reserved

    Bioresorbable Composite Polymeric Materials for Tissue Engineering Applications

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    This review covers the development of bioresorbable polymeric composites for applications in tissue engineering. Various commercially available bioresobable polymers are described, with emphasis on recent bioresorbable composites based on natural and synthetic polymers. Bioresorbable polymers contain hydrolyzable bonds, which are subjected to chemical degradation via either reactive hydrolysis or enzyme-catalyzed active hydrolysis. For synthetic polymers, chemical hydrolysis is the most important mode of degradation. The degradation rate can be controlled by varying the molecular weight and crystallinity. Examples of bioresorbable polymers are: polyurethane, poly(D,L)lactide, poly(lactic-co-glycolic) acid, poly(α-hydroxy acids), cross-linked polyester hydrogels, poly(orthoesters), polyanhydrides and polyethylene glycol
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