113 research outputs found

    Computing Simple Roots by an Optimal Sixteenth-Order Class

    Get PDF
    The problem considered in this paper is to approximate the simple zeros of the function by iterative processes. An optimal 16th order class is constructed. The class is built by considering any of the optimal three-step derivative-involved methods in the first three steps of a four-step cycle in which the first derivative of the function at the fourth step is estimated by a combination of already known values. Per iteration, each method of the class reaches the efficiency index , by carrying out four evaluations of the function and one evaluation of the first derivative. The error equation for one technique of the class is furnished analytically. Some methods of the class are tested by challenging the existing high-order methods. The interval Newton's method is given as a tool for extracting enough accurate initial approximations to start such high-order methods. The obtained numerical results show that the derived methods are accurate and efficient

    Biosystematic study of (Clupeidae) Alosa in Mazandaran and Golestan province coastal waters

    Get PDF
    This survey is part of identification and determination of clupeidae (Genus Alosa), in southern Caspian Sea, Mazandaran and Golestan Province coastal waters during 1997-99. In this study, total of 336 fish samples were studied. The results showed that 4 species of clupeidae, belong to: Alosa brashnikowii (Borodin, 1904), A. caspia (Eichwald, 1983), A. saposchnikowii (Grimm, 1887) and A. kessleri (Grimm, 1887). For species identification two morphometric and morphomerestic factors were used. One of the important factors of morphometric is gill rakers and, A. braschnikowii had 20-40 with average of 30.93±6.11, A. caspia had 110-125 with average of 118.3±5.23, A. kessleri had 60-73 with average of 66.82±3.31 and A. saposchnikowii had 20-48 with of average of 32.83 ±4.93 percent gill rakers. Another important morphometric factors are percent ratio of eye diameter to total length. A. braschnikowii had 2.9-5.82 and average of 4.72±0.53 percent, A. caspia had 5.73-7.46 and average of 6.21±0.52, A. saposchnikowii had 6-9.33 and average of 7.3±1.8 percent and finally, A. kessleri had 4.27-6.48 and average of 5.46 ±0.71 percent

    Migration paths saturations in meta-epidemic systems

    Full text link
    In this paper we consider a simple two-patch model in which a population affected by a disease can freely move. We assume that the capacity of the interconnected paths is limited, and thereby influencing the migration rates. Possible habitat disruptions due to human activities or natural events are accounted for. The demographic assumptions prevent the ecosystem to be wiped out, and the disease remains endemic in both populated patches at a stable equilibrium, but possibly also with an oscillatory behavior in the case of unidirectional migrations. Interestingly, if infected cannot migrate, it is possible that one patch becomes disease-free. This fact could be exploited to keep disease-free at least part of the population

    Measuring Sexual Performance: Development and Psychometric Properties of the Sexual Performance Questionnaire in Iranian People with Spinal Cord Injury

    Get PDF
    Sexual performance refers to activities served by sexual capacity and motivation. As a culturally sensitive issue, to date the scalar invariance of sexual performance has not been examined for Iranians with spinal cord injuries (SCIs). Aim: To develop and assess properties of an instrument evaluating sexual performance of an Iranian population with SCIs., in Brain and Spinal Cord Injury Research Center (BASIR), Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran. Using multi-modal methods, we developed and assessed the Sexual Performance Questionnaire (SPQ). This included collecting expert opinions; engaging with patients with SCI referred to BASIR; pilot testing to assess the scale; and a formal investigation. Participants (men = 156, women = 58) completed the SPQ. Internal consistency and reliability were measured using Cronbach’s α coefficient. Content and face validity were examined by academic experts. Construct validity was assessed by examining convergent and discriminant validity. Finally, exploratory factor analysis was used to extract the factor structure of the questionnaire. The Cronbach’s α coefficient was 0.77. There was a significant (p = 0.04) correlation (r = − 0.23) between the SPQ score and age. Those with a partner scored higher (p = 0.001). We found three components: Spouse as initiator, self-initiation, and genital-oriented sex which accounted for 59 of the observed variance. The face and content validity was approved by an expert committee. The development and application of the 13-item SPQ provides a thorough understanding of sexual performance amongst persons with SCI. It facilitates the development of efficient sexual rehabilitation interventions and SCI-specific sexuality education programs. © 2020, Springer Science+Business Media, LLC, part of Springer Nature

    Single cell protein production from culture and marine fish wastes

    Get PDF
    The alarming rate of population growth has increased the demand for food production in third-world countries leading to a yawning gap in demand and supply. This has led to an increase in the number of hungry and chronically malnourished people. This situation has created a demand for the formulation of innovative and alternative proteinaceous food sources. Single cell protein production is a major step in this direction. SCP is the protein extracted from cultivated microbial biomass. Algae, fungi and bacteria are the chief sources of microbial protein that can be utilized as SCP. Produced proteins from these microbes have various nutrition values. SCP is the manufacture of cell mass using microorganisms by culturing on available agriculture, industrial wastes and fisheries by products. Fish wastes due to high protein are the most important substrates for SCP production. In this study, SCP production was done from Silver carp and tuna fish wastes (head, tail and vise versa) and cooked water of canned tuna factories. The used microbes were six genus and species of yeasts include Candida utilis, Saccharomyces cereviceae, Rhodotorula, Khyveromyces marxians, Zygosaccharomyces rouxii and Bacillus subtilis and B.licheniformis. The examination was done in bench scale and CSTR bioreactor (Continuous Stirred Tank Reactor). The effects of various parameters such as pH, temperature, time, supplemented substrates, method of inoculation of microbes, rpm were evaluated. Changes of microbial growth and protein contents were tested by using Optical Density (OD) and Makrokjeldal methods respectively. In end of examination, produced protein were extracted and lyophilized. The results showed that protein percentage in bacterial protein was than yeast protein but wet percentage in bacterial protein was low. Production value produced from tuna fish wastes was higher than (30-45 g/l) to Silver carp wastes (25-29 g/l) and cooked water (10-15 g/l). By adding supplemented substrates, production value has been increased. Candida utilis, in comparison other yeasts, has high activation. B.licheniformis has also had more activation than Bacillus subtilis. The results of the effect some parameters on fermentation showed that yeasts and Bacillus in pH= 5.4 and 32oC and pH=6.9 and 35oC were better than growth pH=6 and 25oC and pH=6.5 and 30oC respectively. Time of fermentation in batch and bioreactor was 54 and 21 hours respectively. High rpm has been caused increasing of microbial growth in bioreactor. The conclusion showed that with optimizing of the growth condition such as some parameters (pH, temperature, substrates and so on) produced SCP with high efficiency. However, produced SCP should be exanimated with other specific tests such as amino acid and fatty acid profiles, minerals, nucleic acids and so on. After full examination, this SCP as probiotic could be used in fish and poultry feed

    Production of fish cheeses from silver carp by acid coagulation

    Get PDF
    Fish and fishery products have high nutrition value particularly omega-3 fatty acids. It is expected that the estimated production in 2030 will be 150 to 160 million tones but estimated demand will be 183 million tons. Processing of fish especially (culture fish) is one of the way attentions of people to fish and fishery products. Fish Finger, Fish Berger, Cracker, Fish Ball are the most important of fishery products. In this research was studied production of fish cheese from Silver carp (Hypophthalmichthys molitrix) from sarcoplasmic proteins. After primary preparation of fish (beheading, cutting, filleting and deboning) minced fish was washed with salt solution (0.01, and 0.04 mol) and were isolated sarcoplasmic proteins. Acetic acid (%5) and centrifuge were used for sedimentation and extraction of these proteins. Fifteen formulas were worked for preparing of fish cheese. Minced fish, sedimented protein and fish cheese were examinated for proximal parameters (protein, ash. moisture, carbohydrate and lipid) and microbial and chemical spoilage factors (Total Viable Count, Mold and Yeast, Total Volatile Nitrogen, and Peroxide Value). The shelf life and organoleptic characterization of fish cheese were also surveyed. The results indicated that mean of protein, lipid, ash, moisture and carbohydrate in fish cheese were %14/86, %28/01, %3/46, %48/27, %4/78 respectively. The best formula was treatment of 13 with %18/26 of protein. TVN and PV, in fish cheese, were at standard level but after 30 days stored in 4o C, PV value ere slowly increased. Microbial parameters, in product, (in zero time) were log 3 and 4 but after 30 days were log 4 and 5. Organoleptic factors such as odor, frangibility, taste in fish cheese in zero and 30 days were good and medium respectively. Cost of fish cheese was varied between 2000 to 27000 Rails. As fish cheese is prepared from sarcoplasmic proteins and was not any use from fish tissue, therefore it can be produced as secondary products in processing plants and can be introduced to people as new fish product

    Survey of diversity, distribution, abundance and biomass of macrobenthic fauna in the southern Caspian Sea

    Get PDF
    Sediments samples were collected using Veen Grab Sampler (0.1 square meter) at 8 transects namely Astara, Anzali, Sefidroud, Tonekabon, Noshahr, Babolsar, Amirabad, Torkman in the southern of Caspian Sea. Five stations were selected at 5, 10, 20, 50 and 100 meter depths in each transect. Sediments were sampled triplicate at each station. Samples also were collected during four seasons (spring (May), summer (July), fall (November) and winter (January)) in 2009. Results of this study showed that species composition of Macrobenthos consisted of 32 species which belonged to 7 families of Polychaeta, Crustacea and Bivalvia at studied area. In addition, Oligochaeta identified in “Class”, Chironomidae considered in Insecta categories “Family” and Streblospio spp. (Polychaeta) was recognized in “Genus”. Gammaridae and Pseudocumidae of Crustacea with 12 and 10 species had the highest species diversity compared to other groups, respectively. Polychaeta was consisted 75.5 percent of total abundance of macrobenthos which the major abundance (equal 62.4% of total abundance) were belong to Streblospio spp. from Spionidae family, while its biomass was equals 5.11% of total macrobenthos. In contrast, Cerastoderma lamarcki species from Bivalvia Class with only 1.7% of total abundance of macrobenthos allocated 69 percent of total biomass. In the southern of Caspian Sea, average total abundance was significantly less at 4 western transects (Astara, Anzali, Sefidroud, Tonekabon) compared to 4 eastern transects (Noshahr, Babolsar, Amirabad, Torkman) (p<0.05). The highest average abundance of macrobenthos (10655±1246SE ind/m^2) was observed at transect of Torkman, and lowest value (4032 ± 686SE ind/m^2) was recorded at transect of Sefidroud (p< 0.05). Generally, minimum species diversity were obtained at 20 m depth in all transects and the maximum value was observed at 5 m depth in most of transects (p<0.05). In contrary, maximum average abundance of Macrobenthoses was at 20 m depth in transects of Anzali, Sefidroud, Tonekabon, Nowshahr and Amirabad compared to other depths. Macrobenthoses abundance average in 5 m depth (except Astara and Torkman) was less than other depths in 6 transect (p < 0.05). Total average abundance and biomass of macrobenthos was 5976±583SE ind/m^2 and 43.675 ± 11.402SE gr/ m^2, respectively. Maximum and minimum of abundance of macrobenthos were observed in summer (7714±778 ind/m^2) and winter (4071 ± 340 ind/m^2), respectively. Maximum and minimum of biomass of macrobenthos were obtained in fall (50.271±13.258SE gr/ m^2) and in summer (35.123 ± 8.903SE gr/ m^2), respectively (p< 0.05). Percent of total organic matter (TOM) were low in 5 and 10 m depths and increased toward offshore depths. TOM percent was 2.06±0.11SE at 10 m depth and increased to 4.62 ±0.17SE in 100 m depth. Percent of silt and clay (grains size less than 63 micron) had positive significantly correlation with percent of TOM (p<0.01).While they had negative significantly correlation with percent of sand (grains size between 63 and 1000 micron) (p<0.01). Percent of silt and clay like organic matter, had ascending trend toward to depth increased and varied from 44.4 ± 4.06SE percent in 5 m depth to 96.5 ± 0.59SE percent in 100 m depth. In contrast, percent of sand decreased toward depth and varied from 54.5 ± 4.13SE percent in 5 m depth to 2.8 ± 0.53SE percent in 100 m depth. Result of current study showed that total abundance of macrobenthoses had positive significantly correlation with TOM percent (p<0.01) and silt/clay percent (p<0.05). Abundance of Oligochaeta had positive significantly correlation (p< 0.01) with TOM and silt/clay percent. Two groups of Polychaeta, Gammaridae and Cerastoderma lamarcki had negative significantly correlation with TOM and silt/clay percent (p< 0.01), and every four aforementioned groups had positive significantly correlation with sand percent (p< 0.01). Overall, different correlation between abundance of various macrobenthos groups and TOM percent and type of grain size of sediment could be related to fluctuation of abundance of various macrobenthos groups at difference transects and depths. On the other hand, in study area were occurred simultaneously some phenomena such as increased abundance of Oligochaeta and Polychaeta, dominance of Streblospio Genuse (Polychaeta group), and decreases abundance of Bivalvia and appearance of Menemiopsis leidyi which need to study more and monitoring of this area

    The comprehensive study of possibility ecological control Mnemiopsis leidyi in Caspian Sea activity: The study and recognization parasitic fauna and Bacterial flore in ctenophore (Mnemiopsis leidyi and Bereo ovata)

    Get PDF
    Bacterial flora and parasitic fauna of M. leidyi an exotic invader jelly fish to Caspian Sea ecosystem and B. ovata to Black sea an alternative biological control agent was studied. During summer 1382 to spring 1383, using routine Bacteriological work. 72 sample of sea water Caspian Sea obtained from depth 20 and 50 meters, 36 sample of M. leidyi from depth 20 meters, 10 sample of B. ovata and 3 sample of sea water (Black sea) were collected and according to Bacteriological was studied. 216 sample of M. leidyi from depth 10 to 50 meters of Caspian Sea and 47 sample of B. ovata from Black and Marmarreh Sea (Turkey) were collected and was studied. In this study no parasite from was identified in M. leidyi (Caspian sea) but 64 percentage and 73 percentage of B. ovata (Marmarreh and Black sea respectively) contaminated to Trichodina ctenophore at varians concentration B. ovata of Black sea (130 min 1050 max) and B. ovata Marmarre sea (420 min 2100 max). While B. ovata kept at high salinity of 21 ppt was more contaminated with this pretrichial protozoan (Trichodina) than in low salinity (12/5 ppt). in comparision of bacterial flore in two cetenophore (M. leidyi and B. ovata) was observed that some of bacteria such as micrococcus sp, Aeromonas sp. Bacillus coagulans in both ctenophore and some other bacteria such as Agromobacterium and chromobacterium only observed in B. ovata but other researcher have reported fram Caspin sea and some of bacteria to specific Shewanella , Vibrio harveiy and bacillus linens was observed in B. ovata . Of course specific bacteria cannot transfer to Caspian Sea (different of salinity black sea (2/1%) to Caspian Sea (1/25 %)). Therefore if B. ovata to introduce to south Caspian Sea for biological control population M. leidyi. it is necessary at first some of viral pathogen in aquatic animal (fish) such as VNN, IPN,IHN,VHS,SVC was studied and then with confidence 95% non-infestation B. ovata to viruses and pass from bath anti parasite and anti-bacterial must be introduce to south Caspian sea

    Stock assessment of the bony fishes in Iranian coastal waters of the Caspian Sea (2005-2007)

    Get PDF
    Exploitation of bony fishes resources started on 12 October 2005 and finished on 9 April 2006 in 2005-2006. 142 beach seines caught about 14333.4 tons of bony fishes by 47101 hauling. The total catch was estimated 21844.7 tones (Includes illegal fishery). Kutum, mullets and common carp comprised more than 97 percent of total catch. Length classes 39-40, 31-32 and 40-41 cm predominated for kutum, golden grey mullet and common carp, respectively. Age groups 3 to 5 year comprised 84.2, 74.8 and 83.7 percent for Kutum, golden grey mullet and common carp, respectively and age group 4 year was dominant with 42.0, 35.9 and 43.0 percent, respectively. K value and L_∞ calculated 0.26 (/year) and 58.3 cm for Kutum and 0.15 (/year) and 61.5 cm for golden grey mullet, respectively. The total biomass and MSY estimated about 24733.7 and 8550.4 tones for kutum and about 16948.0 and 4999.0 tones for golden grey mullet, respectively. Exploitation rate (E) calculated 0.71 and 0.70 for Kutum and golden grey mullet, respectively. In 2006-2007, the exploitation of bony fishes resources started on 12 October 2006 and finished on 7 April 2007 in 2006-2007. 134 beach seines caught about 14120.0 tons of bony fishes by 48470 hauling. The total catch was estimated 23801.8 tones (Includes illegal fishery). Kutum, mullets and common carp comprised more than 98.5 percent of total catch. Length classes 39-40 and 38-39 cm predominated for kutum and common carp, respectively and length classes 27-28 and 29-30 cm predominated for golden grey mullet. Age groups 3 to 5 year comprised 80.2 and 71.8 percent for kutum and golden grey mullet, respectively and age groups 4 to 6 year comprised 71.8 percent for common carp. Age group 3, 4 and 5 year was dominant with 35.5, 32.1 and 27.1 percent for kutum, golden grey mullet and common carp respectively. K value and L∞ calculated 0.27 (/year) and 60.7 cm for Kutum, 0.2 (/year) and 58.4 cm for golden grey mullet and 0.19 (/year) and 66.7 cm for common carp, respectively. The total biomass and MSY estimated about 46654.9 and 14801.4 tones for Kutum, about 19549.0 and 5748.4 tones for golden grey mullet and about 10584.3 and 2186.0 tones for common carp, respectively. Exploitation rate (E) calculated 0.69, 0.53 and 0.52 for kutum, golden grey mullet and common carp, respectively
    corecore