Reproduction and spawning patterns of the Scomberomorus commerson in the Iranian coastal waters of the Persian Gulf & Oman Sea

Reproduction and spawning patterns of the king fish (Scomberomorus commerson) were studied in the Persian Gulf (Hormozgan Province) and Oman Sea from Oct 2006 to Sep 2007. A total of 1120 fish was collected from different landing sites along the Iranian waters. Yearly analysis of the reproductive stages and gonadosomatic index showed a single reproductive cycle beginning in March and continued with a single spawning period from August to September. The mean length at first maturity (Lm 50%) for females was 83.6 Cm. The sex ratio was M:F = 0.97:1 which was not significantly (P > 0.05) different among samples (χ2 test). Isometric growth for this species was approved

Do Patients with Penetrating Abdominal Stab Wounds Require Laparotomy?

Background: The optimal management of hemodynamically stable asymptomatic patients with anterior abdominal stab wounds (AASWs) remains controversial. The goal is to identify and treat injuries in a safe cost-effective manner. Common evaluation strategies are local wound exploration (LWE), diagnostic peritoneal lavage (DPL), serial clinical assessment (SCAs) and computed tomography (CT) imaging. Making a decision about the right time to operate on a patient with a penetrating abdominal stab wound, especially those who have visceral evisceration, is a continuing challenge. Objectives: Until the year 2010, our strategy was emergency laparotomy in patients with penetrating anterior fascia and those with visceral evisceration. This survey was conducted towards evaluating the results of emergency laparotomy. So, better management can be done in patients with penetrating abdominal stab wounds. Patients and Methods: This retrospective cross-sectional study was performed on patients with abdominal penetrating trauma who referred to Al- Zahra hospital in Isfahan, Iran from October 2000 to October 2010. It should be noted that patients with abdominal blunt trauma, patients under 14 years old, those with lateral abdomen penetrating trauma and patients who had unstable hemodynamic status were excluded from the study. Medical records of patients were reviewed and demographic and clinical data were collected for all patients including: age, sex, mechanism of trauma and the results of LWE and laparotomy. Data were analyzed with PASW v.20 software. All data were expressed as mean ± SD. The distribution of nominal variables was compared using the Chi-squared test. Also diagnostic index for LWE were calculated. A two-sided P value less than 0.05 was considered to be statistically significant. Results: During the 10 year period of the study, 1100 consecutive patients with stab wounds were admitted to Al-Zahra hospital Isfahan, Iran. In total, about 150 cases had penetrating traumas in the anterior abdomen area. Sixty-three (42%) patients were operated immediately due to shock, visceral evisceration or aspiration of blood via a nasogastric tube on admission. Organ injury was seen in 78% of patients with visceral evisceration. Among these 87 cases, 29 patients’ (33.3%) anterior fascia was not penetrated in LWE. So, they were observed for several hours and discharged from the hospital without surgery. While for the remaining 58 patients (66.6%), whose LWE detected penetration of anterior abdominal fascia, laparotomy was performed which showed visceral injuries in 11 (18%) cases. Conclusions: All in all, 82 percent of laparotomies in patients with penetrated anterior abdominal fascia without visceral evisceration, who had no signs of peritoneal irritation, were negative. So, we recommended further evaluation in these patients. However, visceral evisceration is an indication for exploratory laparotomy, since in our study; the majority of patients had organ damages

A Novel Two-Channel Continuous-Time Time-Interleaved 3rd-order Sigma- Delta Modulator with Integrator-Sharing Topology

this paper presents a 3rd-order two-path Continuous-Time Time-Interleaved (CTTI) delta-sigma modulator which is implemented in standard 90nm CMOS technology. The architecture uses a novel method to resolve the delayless feedback path issue arising from the sharing of integrators between paths. By exploiting the concept of the time-interleaving techniques and through the use time domain equations, a conventional single path 3rd-order Discrete-Time (DT) ΔΣ modulator is converted into a corresponding two-path Discrete-Time Time-Interleaved (DTTI) counterpart. The equivalent Continuous-Time Time-Interleaved version derived from the DTTI ΔΣ modulator by determining the DT loop filters and converting them to the equivalent Continuous-Time (CT) loop filters through the use of the Impulse Invariant Transformation. Sharing the integrators between two paths of the reported modulator makes it robust to path mismatch effects compared to the typical Time-Interleaved (TI) modulators which have individual integrators in all paths. The modulator achieves a dynamic range of 12 bits with an OverSampling Ratio (OSR) of 16 over a bandwidth of 10MHz and dissipates only 28mW of power from a 1.8-V supply. The clock frequency of the modulator is 320MHz but integrators, quantizers and DACs operate at 160MHz

NEUTRINOS FROM PRIMORDIAL BLACK HOLES

The emission of particles from black holes created in the early Universe has detectable astrophysical consequences. The most stringent bound on their abundance has been obtained from the absence of a detectable diffuse flux of 100 MeV photons. Further scrutiny of these bounds is of interest as they, for instance, rule out primordial black holes as a dark matter candidate. We here point out that these bounds can, in principle, be improved by studying the diffuse cosmic neutrino flux. Measurements of near-vertical atmospheric neutrino fluxes in a region of low geomagnetic latitude can provide a competitive bound. The most favorable energy to detect a possible diffuse flux of primordial black hole origin is found to be a few MeV. We also show that measurements of the diffuse $\nu _\tau$ flux is the most promising to improve the existing bounds deduced from gamma-ray measurements. Neutrinos from individual black hole explosions can be detected in the GeV-TeV energy region. We find that the kilometer-scale detectors, recently proposed, are able to establish competitive bounds.Comment: 19 pages plus 9 uuencoded and compressed postscript figure

The study on fishing and resource management of kilka fisheries within southern Caspian Sea

The project of the Study on fishing and resource management of fisheries within Southern Caspian Sea was conducted on the base of an agreement made between fisheries organization (Shilat) and the Iranian fishery research organization (IFRO) signed in 2010. The study has several phases. The final report of the fishery on fishing and resource management of fisheries within Southern Caspian Sea (Gilan, Mazandaran & Golestan provinces) is consisted of several sections such as: 1- The Survey status of biology and catch of Kilka fishes , Bony fishes and Estrogen fishes and also the status of aquatic resource conservation in the Southern part of Caspian Sea 2- Fishing analysis in the Southern part of Caspian Sea 3- Fisheries development Strategies, policies and plans in the Southern part of Caspian Sea In this survey and library-based study, internal and external environmental factors of shilat activities are considered. Using SWOT analysis method, current situation of fisheries is investigated. In this regard, all fisheries activities were divided into four groups, then, the strengths, weaknesses, opportunities and treats of internal and external environment will be analyzed. A considerable number of tables and matrixes were prepared and policies and strategies as seen of final report were carried out

Study forming of growth rings in the Caspian bony fishes (Step 1: Common carp Cyprinus carpio Linnaeus, 1758)

The ichthyology studies at fish tagging was referred to more than 100 years ago. Tagging is utilized for the estimation of stock amount, population frequency and project or calculating of survival and growth value. There are many various methods for fish tagging are used for juvenile to adult fish. The current study was carried out at Ghare-su research station during 2011-2013. 250 of carp fingerlings (Cyprinus carpio) were tagged by bath with tetracycline manner (pH=6, 500mg/l). The fork length and weight of fish were 10-12 mm and 2-4 g, respectively. Also, fish were fed twice a day. The second and third tagging stages were performed at November 2012 and July 2014, respectively. After otolith was extracted, it was washed water and dry at lab room air. The tagged rings or loops (annuali) were observed by lab loupe with 10X and 40 X magnifications. The results showed that a narrow band was formed after the first tagging of carp fingerlings, as it was seen at the end of otolith edge. It was demonstrated that tetracycline was absorbed and the tagged ring or loop (annuli) was newly formed at external or out of othlith edge. There was not observed any fish death, when carp fingerlings were tagged by OTC bath manner. It said that the first OTC band will be seen, the first sign of the formed OTC band was observed at external margin of otoilith after 6th month , of course , from 4th month, this sign was formed at the most external of otoilth edge but with added the following region, it can be hardly distinguished. The formed band in relative to second tagging was similar to the first band but there was no discrepancy or difference with together

The study of fluctuation of large pelagic stock (yellowfin tuna, skipjack tuna, longtail tuna, Narrow-barred Spanish mackerel) in order to optimum exploitation in the Persian Gulf & Oman sea

The study of fluctuation of large pelagic stock (yellowfin tuna, skipjack tuna, longtail tuna, Narrow-barred Spanish mackerel ) in order to optimum exploitation in the Persian Gulf & Oman sea This study was carried out from 2005-07 in order to acquire some biological characteristics and population dynamic parameters for stock management and responsible fisheries. Thunnus albacares (yellowfin tuna), katsuwonus pelamis (skipjack tuna), Thunnus tonggol (longtail tuna) and scomberomorus commerson (Narrow- barred Spanish mackerel) were sampled. In total, length frequency of 9345 specimens of yellowfin tuna were analyzed. Size range was 37-172 cm. Teleost fishes were the most dominant prey species observed in this study (42%), Occurrence of Potunus Pelagicus was found to be the second (28%).Sthenoteuthis oualaniensis (22%), Natosquilla (5%) and octopus (3%) also were identified in the gut content of the yellowfin tuna. Length of maturity (50%) of yellow fin tuna was estimated 77.2 cm and spawning season was started from May. 8443 specimens of skipjack with size range of 32-90 cm were sampled. 48% of food items were teleost fishes. Squid and shrimp were also identified. Spawning season was begun from June. Growth parameters & fishing mortalities of yellow fin tuna and skipjack tuna were also estimated. Size range if longtail tuna was from 26-125cm Length infinity was estimated 132.3 cm with growth parameter of 0.35 per year. In total 10451 specimens of narrow- barred Spanish mackerel were sampled. Size range was from 20-164 cm. Teleost fishes were the most dominant prey species observed in the study (91.3%). Crustaceans (0.6%) and Indian squid (0.2%) also were identified in the specimens. Length maturity (50%) was estimated 83.6cm

The study on fishing and resource management of bony fisheries within southern Caspian Sea

The project of the Study on fishing and resource management of fisheries within Southern Caspian Sea was conducted on the base of an agreement made between fisheries organization (Shilat) and the Iranian fishery research organization (IFRO) signed in 2010. In this library-based study the current situation of bony fish fisheries and biology of these species has been surveyed in Iranian waters of the Caspian Sea . In this survey internal and external environmental factors of bony fishes activities were considered. Using SWOT analysis method, current situation of fisheries was investigated..One of the most important strategies for conserving anadromous species such as Caspian kutum , common carp, roach, bream and …. is rehabilitation of the natural spawning ground in rivers, coastal lagoon specially Anzali lagoon .By conducting this strategy not only restocks of bony fishes is done ,but also reduced the cost of artificial restocking programs and releasing fingerlings .In short term , it is nessesary to enhance the stocks of the species that have low catch is done by huge releasing of the fingerlings and study the qualification of the program

Ecological interaction between commercial fishes in the Persian Gulf

An ecosystem-based management fishery is a new way of looking at management of living resources. Trophic levels of basic food items, feeding habits, growth and mortality rate of 20 exploited fish species (including commercial and bycatch) are investigated in the Persian Gulf (from the provinces of Khuzestan, Bushehr and Hormozgan) from 2010 to 2012. The model considers trophic interactions among 12 functional group of the ecosystem involving Phytoplankton, Zeoplankton, Cephalopods, Shrimp, Infauna Benthos, Epifaunal Macrobenthos, Demersal Zoobenthos Feeders, Small Pelagic Planktivorous Fish, Benthoplagic Feeder, Piscivorous, Large Benthic Carnivores And Small Benthic Carnivores. In general 7452 of stomach contents samples were analyzed based on the weight and numerical method and were detected about 40 preys. The results demonstrated gaps in our knowledge on the food web structure. The mean trophic levels were varied from L. klunzingeri (2) to S. tumbil (4.64), while the total catch of some species were fluctuating widely. Result of our study showed that Total mortality varied between 0.45 per year (A. suppositus) to 9.5 per year (P. indicus) and food consumption rate also fluctuated by 1.9 (L. johni ) to 89 (L. lineolatus). The results indicated that some fish species including sardine, Anchovies, small carangids, S. stridens with high frequency in ecosystem, have been occupied in the food web as a wasp-waist. The model showed that most hunters groups live in middle levels in the food web such as N. japonicas, A. latus, P. kaakan, L. nebolusus, P. indicus and T. lepturus . Analysis the catch rate during 2001-2011 reveled that there is a clear trend of declining most of fish species catches in this research except for T. lepturus, P. kaakan and sparids which lead to upset the fundamental ecological balance of the Persian Gulf in future

Biomass estimation of demersal resources in the Persian Gulf and Oman Sea by Swept Area Method

Regarding to monitor of demersal resources in the Persian Gulf and Oman Sea, and also biomass and CPUA estimation of them, a series of research cruises (5 cruises per year) were carried out by R/V Ferdows-1covering the area from 49 00 E in the west (Khoozestan provice) to 61 25 E in the east (Gwater) in a 5 years program form 2004 up to 2008 (no cruise in 2006). The study area was stratified into 17 strata (A to Q) of which 10 starta (A to J) were in the Persian Gulf and 7 strata (K to Q) were in the Oman Sea, covering the depths of 10-50m in the Persian Gulf and 10-100m in the Oman Sea. A total of 316 stations were randomly selected. The biomass and CPUA were estimated by Swept Area method. The comparison between two regions indicated that the percentage of density of demersal fishes in the Persian Gulf during years 2004, 2005, 2007 and 2008 were 3.3, 3.9, 2.3 and 2.4 times more than the Oman Sea and totally 70-80% of total biomass was calculated for the Persian Gulf. Also a comparison among 17 starta, the highest biomass was found for starta C & D in the Bushehr province waters. The amount of CPUA for both regions of the Persian Gulf and Oman Sea was compared and it was concluded that in years 2004 and 2005, the mean CPUA in the Persian Gulf was partially higher than the Oman Sea with 1.06 & 1.20 times more; and on the contrary for the next two years this value was higher in the Oman Sea with 1.3 times more. The highest CPUA of demersal resources for the Oman Sea belonged to the strata K & O for years 2004, 2007 and 2008 and for year 2005 was for L and strata. It can be concluded that the north-west of Oman Sea has the best condition of biomass of commercial and non-commercial species and the O stratum will be in the second ranking. With review the mean CPUA in different depth-layers for years 2004, 2005, 2007 and 2008, it was concluded that with increasing the depth, the mean CPUA is decreased in which the CPUA values in depth-layer 10-20m for these years were 8.3, 3.0, 2.1 & 1.6 times more than depth-layer 50-100m. The comparison of mean CPUA for 10 strata of the Persian Gulf showed that in years 2004 and 2005, the mean CPUA of demersal fishes in the Hormuzgan province waters was higher than in Bushehr province waters (1.2 times more). In total, the highest maen CPUA belonged to F (Naiband to Mogham) and G (Mogham to Farour) in Hormuzgan waters. On the contrary, in years 2007 and 2008 this value in Bushehr waters was 1.3 times higher than western part of Hormuzgan waters with the highest value in D stratum(Boordekhoon to Dayyer). Also the comparison of mean CPUA for different depth-layers, it was found that the mean CPUA has ascending trend with increasing the depth, with the highest value in depth-laer of 30-50m in which contains the 55-68% of total biomass. The lowest biomass is found in depth-layers of 10-30m. Totally, the minimum CPUA and biomass for both commercial and non-commercial species belonged to a stratum located in Khouzestan province waters and it was shown the over-exploitation of resources in this area. The comparison between commercial and non-commercial groups in both ecosystems , it was concluded that the density of commercial species was higher than non-commercial ones , and in all years the Persian Gulf indicated higher values than the Oman Sea