scholarly journals Reproductive traits of Goby Glossogobius sparsipapillus Akihito and Meguro, 1976 in Tra Vinh Province, Vietnam

2021 ◽  
Vol 42 (3(SI)) ◽  
pp. 879-886
Author(s):  
N.K. Ho ◽  
◽  
T.M. Nguyen ◽  
Q.M. Dinh ◽  
◽  
...  

Aim: This study was conducted to contribute data on the reproductive biology such as sex proportion, spawning season and pattern, fecundity and its relation to fish size, and length at first mature of the commercial fish Glossogobius sparsipapillus in Tra Vinh province, Vietnam. Methodology: Fish was collected monthly using trawling nets at four sampling sites during dry and wet seasons between July 2019 to June 2020. Next, fish was stored in ice before transporting to the laboratory. In laboratory, total length, body weight, and sex before removing gonads were examined histologically. Results: Female G. sparsipapillus (806 individuals) out numbered males (591 individuals). This goby was a multi-spawner as different developmental stages of oocytes and spermatocytes were present in the cross-section of testes and ovaries. A combined analysis of frequency of mature ovaries and GSI showed that this goby could spawn throughout the study period with the mean peak from July to October. The batch fecundity was 17,537 SE and related positively to fish length and weight, indicating it increased as fish grew Interpretation: This study results in an enhanced understanding of this species' reproductive biology for better sustainable management and brood stock study in studied regions.

2019 ◽  
Vol 1 (2) ◽  
Author(s):  
Khin May Chit Maung ◽  
Phan Minh-Thu ◽  
Nyo Nyo Tun

Reproductive biology of Leiognathus splendens was studied by using the samples collected from the catches of trawl fisheries in Myeik coastal waters during January to December 2014. Spawning takes place throughout the year, with a peak during April-May and September-December. The observed length at first maturity was 9.0 cm total length in males and 8.4 cm in females. The mean gonadosomatic index was more prominently in females (2.5) than males (1.5). Sex ratio (1 male: 1.1 females) also indicates the general dominant of females over males  Fecundity varied from 6120 to 58412 eggs. Relationship of fecundity to fish length, fish weight and ovary weight showed that fecundity is more related to the gonad weight (r=0.9) than length (r=0.8) and weight of fish (r=0.7)


Author(s):  
Yuri Aleksandrovich Severov ◽  
Firdauz Mubarakovna Shakirova ◽  
Vladimir Vyacheslavovich Kuznetsov ◽  
Vyacheslav Alekseevich Kuznetsov

The results of six-year observations (2012-2017) in the Meshinsky Gulf of the Kuibyshev reservoir concerning the evaluation of the reproduction efficiency of the main commercial fish of this section of the reservoir have been reviewed and analyzed. Data are given on the species composition of prolarvae and larvae of fish in the coastal part of the reservoir. It has been established that the most abundant in the studied years was the fry of roach, bream and silver bream; the larvae of carp and ruff were least common in catches. A method for estimating yields by catches of fish larvae based on deviations in the mean value of the catch has been proposed. According to these data, in 2012-2017 there was one high-yielding generation, in the remaining years - medium-yielding. It is shown that the dynamics of the number of fish larvae in the coastal region depends on the course of spawning and obeys the normal distribution in time. Analysis of the relative indices of the quantity of larvae - pieces/catches and pieces/1m of the coastal area in the studied years has been given. A method is described for calculating the absolute abundance of fish larvae in the littoral by the example of the Meshinsky Gulf. According to calculated data, the average number of early juveniles in the littoral of the Meshinsky Gulf in 2012-2017 was about 4 billion specimens, which corresponds to the figures obtained in previous years in the Sviyazhsky Gulf of the Kuibyshev Reservoir. The study results have great practical importance and can serve as data for prediction of catches and determining the state of ecological system of the reservoir.


2021 ◽  
Vol 23 (2) ◽  
pp. 39-50
Author(s):  
Zeliha Erdoğan ◽  
Hatice Torcu Koç ◽  
Fatih Özdemir

Abstract We studied the reproductive traits in 23 of 190 individuals of Capoeta umbla caught monthly in the Solhan Creek of the Murat River between April 2017 and March 2018. The sex ratio (F:M) was found to be 1:1.11. The macroscopic examination of the gonads and gonado-somatic index indicated that the reproductive period lasted from May to August with peak activity in May. The fecundity ranged from 2,000 to 9,000 oocytes, and it correlated with the total length and body weight. This work represents the first attempt to investigate the reproductive traits of the Capoeta umbla population in the Solhan Creek. The results provide information on the reproductive biology and contribute to the conservation of the fish population and its sustainable management.


2019 ◽  
Vol 1 (2) ◽  
Author(s):  
Khin May Chit Maung ◽  
Phan Minh-Thu ◽  
Nyo Nyo Tun

Reproductive biology of Leiognathus splendens was studied by using the samples collected from the catches of trawl fisheries in Myeik coastal waters during January to December 2014. Spawning takes place throughout the year, with a peak during April-May and September-December. The observed length at first maturity was 9.0 cm total length in males and 8.4 cm in females. The mean gonadosomatic index was more prominently in females (2.5) than males (1.5). Sex ratio (1 male: 1.1 females) also indicates the general dominant of females over males  Fecundity varied from 6120 to 58412 eggs. Relationship of fecundity to fish length, fish weight and ovary weight showed that fecundity is more related to the gonad weight (r=0.9) than length (r=0.8) and weight of fish (r=0.7)


2021 ◽  
Vol 22 (15) ◽  
pp. 8256
Author(s):  
Adolfas K. Gaigalas ◽  
Yu-Zhong Zhang ◽  
Linhua Tian ◽  
Lili Wang

A stochastic model of the flow cytometer measurement process was developed to assess the nature of the observed coefficient of variation (CV%) of the mean fluorescence intensity (MFI) from a population of labeled microspheres (beads). Several sources of variability were considered: the total number of labels on a bead, the path through the laser beam, the optical absorption cross-section, the quantum yield, the numerical aperture of the collection optics, and the photoelectron conversion efficiency of the photomultiplier (PMT) cathode. The variation in the number of labels on a bead had the largest effect on the CV% of the MFI of the bead population. The variation in the path of the bead through the laser beam was minimized using flat-top lasers. The variability in the average optical properties of the labels was of minor importance for beads with sufficiently large number of labels. The application of the bead results to the measured CV% of labeled B cells indicated that the measured CV% was a reliable measure of the variability of antibodies bound per cell. With some modifications, the model can be extended to multicolor flow cytometers and to the study of CV% from cells with low fluorescence signal.


2021 ◽  
pp. 039139882110322
Author(s):  
Frédéric J Baud ◽  
Vanessa Seif ◽  
Pascal Houzé ◽  
Jean-Herlé Raphalen ◽  
Benoît Pilmis ◽  
...  

Introduction: Adsorption of gentamicin in a polyacrylonitrile filter was previously evidenced in a session lasting 6 h using the NeckEpur model. We extended the study over three consecutive days to mimic the 72-h life span of a filter. Methods: Prismaflex® monitor and ST150® filter were used in the continuous diafiltration (CDF) mode at a 2.5 L/h flowrate. The daily session started with a 6-h session of CDF. Thereafter, the 5-L central compartment was changed using a bag free of gentamicin to assess gentamicin release over the following 18 h. Experiments were repeated on Day 2 and stopped at the end of the 6-h session of CDF on Day 3. The experiment was performed in duplicate. Results: At a 2.5 L/h diafiltration flowrate, the mean daily clearances of gentamicin were 5.5, 4.0, and 3.3 L/h, respectively. The mean diafiltration and adsorption ratios in the daily elimination of gentamicin were 32/68%, 58/42%, and 88/12%, respectively. During days 1 and 2, the mean amount of gentamicin released from the ST150® filter were 14 and 34 mg, respectively. Conclusion: The pharmacokinetics of gentamicin over 3 days is strongly altered by adsorption in the same filter with a progressive decrease of elimination by adsorption, suggesting saturation of the filter. One limitation of our study results from the mode of administration using a bolus dose instead of an infusion over 30 min. Adsorption adds a clearance to those of diafiltration. The time-dependency of gentamicin clearance precludes using a constant dosage regimen over the filter’s life span.


Entropy ◽  
2021 ◽  
Vol 23 (4) ◽  
pp. 468
Author(s):  
Pentti Nieminen ◽  
Sergio E. Uribe

Proper peer review and quality of published articles are often regarded as signs of reliable scientific journals. The aim of this study was to compare whether the quality of statistical reporting and data presentation differs among articles published in ‘predatory dental journals’ and in other dental journals. We evaluated 50 articles published in ‘predatory open access (OA) journals’ and 100 clinical trials published in legitimate dental journals between 2019 and 2020. The quality of statistical reporting and data presentation of each paper was assessed on a scale from 0 (poor) to 10 (high). The mean (SD) quality score of the statistical reporting and data presentation was 2.5 (1.4) for the predatory OA journals, 4.8 (1.8) for the legitimate OA journals, and 5.6 (1.8) for the more visible dental journals. The mean values differed significantly (p < 0.001). The quality of statistical reporting of clinical studies published in predatory journals was found to be lower than in open access and highly cited journals. This difference in quality is a wake-up call to consume study results critically. Poor statistical reporting indicates wider general lower quality in publications where the authors and journals are less likely to be critiqued by peer review.


2021 ◽  
Vol 13 (9) ◽  
pp. 5274
Author(s):  
Xinyang Yu ◽  
Younggu Her ◽  
Xicun Zhu ◽  
Changhe Lu ◽  
Xuefei Li

Development of a high-accuracy method to extract arable land using effective data sources is crucial to detect and monitor arable land dynamics, servicing land protection and sustainable development. In this study, a new arable land extraction index (ALEI) based on spectral analysis was proposed, examined by ground truth data, and then applied to the Hexi Corridor in northwest China. The arable land and its change patterns during 1990–2020 were extracted and identified using 40 Landsat TM/OLI images acquired in 1990, 2000, 2010, and 2020. The results demonstrated that the proposed method can distinguish arable land areas accurately, with the User’s (Producer’s) accuracy and overall accuracy (kappa coefficient) exceeding 0.90 (0.88) and 0.89 (0.87), respectively. The mean relative error calculated using field survey data obtained in 2012 and 2020 was 0.169 and 0.191, respectively, indicating the feasibility of the ALEI method in arable land extracting. The study found that arable land area in the Hexi Corridor was 13217.58 km2 in 2020, significantly increased by 25.33% compared to that in 1990. At 10-year intervals, the arable land experienced different change patterns. The study results indicate that ALEI index is a promising tool used to effectively extract arable land in the arid area.


2013 ◽  
Vol 19 (2) ◽  
pp. 171 ◽  
Author(s):  
Saulat Jahan ◽  
Basem Henary

Research in primary health care (PHC) is underdeveloped and scarce, especially in developing countries. It is important to understand the attitudes and aspirations of PHC physicians for the promotion of research. The aim of this study was to determine the attitudes of PHC physician managers toward research in Qassim province and to identify barriers that impede performing research in the PHC system. The study was based on social cognitive theory framework, and was pre-experimental with a ‘one-group pre-test–post-test’ design. The study participants were physician managers in PHC administration, Qassim. The participants’ attitudes were measured by adapting statements from the Attitude Towards Research scale. The intervention was the 1-day training program ‘Introduction to Research in Primary Health Care’. A total of 23 PHC physicians participated in the study. The mean age of the participants was 45.4 (±1.6) years, and the mean years of work experience was 16.2 (±2.2) years. Only one participant had an article published in a peer-reviewed journal. The results of the study showed that PHC physicians had a baseline positive attitude toward research that was further enhanced after participating in an introductory research-training program. During the pre-test, out of the total score of 63, the mean score on attitude toward research was 48.35 (±6.8) while the mean total attitude score in the post-test was 49.7 (±6.6). However, the difference was not statistically significant at P < 0.05. The item with the highest score regarded the role of research in the improvement of health care services, while the lowest-scoring item was about support from administration to conduct research. The participants recognised lack of skills, lack of training and inadequate resources as major barriers in conducting research. Our study results suggest that the PHC physicians’ positive attitudes toward research can be further improved through in-service training. To promote research in PHC in Qassim, regular research-training programs and incentives for conducting research should be provided to the PHC physicians.


1984 ◽  
Vol 106 (1) ◽  
pp. 252-257 ◽  
Author(s):  
D. E. Metzger ◽  
C. S. Fan ◽  
S. W. Haley

Modern high-performance gas turbine engines operate at high turbine inlet temperatures and require internal convection cooling of many of the components exposed to the hot gas flow. Cooling air is supplied from the engine compressor at a cost to cycle performance and a design goal is to provide necessary cooling with the minimum required cooling air flow. In conjunction with this objective, two families of pin fin array geometries which have potential for improving airfoil internal cooling performance were studied experimentally. One family utilizes pins of a circular cross section with various orientations of the array with respect to the mean flow direction. The second family utilizes pins with an oblong cross section with various pin orientations with respect to the mean flow direction. Both heat transfer and pressure loss characteristics are presented. The results indicate that the use of circular pins with array orientation between staggered and inline can in some cases increase heat transfer while decreasing pressure loss. The use of elongated pins increases heat transfer, but at a high cost of increased pressure loss. In conjunction with the present measurements, previously published results were reexamined in order to estimate the magnitude of heat transfer coefficients on the pin surfaces relative to those of the endwall surfaces. The estimate indicates that the pin surface coefficients are approximately double the endwall values.


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