scholarly journals Diel variation in abundance and size of the seabob shrimp Xiphopenaeus kroyeri (Crustacea, Penaeoidea) in the Ubatuba region, Southeastern Brazil

2010 ◽  
Vol 82 (2) ◽  
pp. 369-378 ◽  
Author(s):  
Sabrina M. Simões ◽  
Rogerio C. Costa ◽  
Adilson Fransozo ◽  
Antonio L. Castilho

The objective of the present study was to analyze diel variation in the abundance and size of the seabob shrimp Xiphopenaeus kroyeri in the Ubatuba region, state of São Paulo, during the year 2000. In each season of the year, collections were made in the day and at night on 9 transects at depths ranging from 2 to 40 m. The estimated shrimp amount was of 28,878 individuals. Although the catch rate was higher during the day (15,853 shrimp), this did not differ significantly from the catch at night (13,025). The catch rate was higher in daytime on most transects, but was higher at night at locations where fine and very fine sand predominated. The majority of juveniles were caught during the day. The mean size (CL) was 14.43 ± 4.02 mm for day and 14.82 ± 4.28 mm for night samples, and the difference was significant (Student's t-test, df = 2, 429, t = 2.27, p = 0.02). The largest individuals were caught during the night. None of the three models that have been proposed in the literature to account for differences in the diurnal catch pattern of penaeid species can be applied to X. kroyeri. Our results provide evidence that sediment type not only influenced the catch rate in the analyzed periods, but also determined which models might fit the behavior of this species.

2014 ◽  
Vol 62 (3) ◽  
pp. 225-234
Author(s):  
Mateus Lopes ◽  
Adilson Fransozo ◽  
Antonio Leão Castilho ◽  
Rogerio Caetano da Costa

Diel variation in the abundance and size of Pleoticus muelleri in the Ubatuba region was investigated during 2000. During each season of the year, sampling was conducted during the day and at night at 8 depths, from 5 to 40 m. The estimated number of shrimp was 955 individuals, 272 collected during the day and 683 at night. There was a difference in the abundance of P. muelleri between day and night (χ², p=2.33E-40). The abundance during the day and at night differed by season with the exception of the spring (χ², p=0.06). The abundance during both periods also differed by depth, except at 15 and 30 m, where it was not significant (χ², p=0.84 and 0.06, respectively). The shrimp caught at night were generally smaller than those caught during the day (Kolmogorov-Smirnov, p<0.01). Pleoticus muelleri juveniles were found primarily at night. This tendency could have influenced the lower mean size for this period. The sediment type and the bottom temperature appear to influence the behavior of this species and consequently the catch rate during the periods analyzed.


2020 ◽  
pp. 77-83
Author(s):  
Zhanna Kalmatayeva

The purpose of the article was to study the problems of domestic violence of women and its consequences in Kazakhstan. The analysis of the results of the study of self-attitude and self-esteem of women subjected to domestic violence. Revealed there is a correlation between the level of self-attitude of domestic violence victims and the non-differentiated I-concept. 140 women participated in the present study, 70 women are control group which not subjected to domestic violence and 70 women of them who have currently reported domestic violence in the Crisis Center "Umit" in Nur-Sultan in the period from November 2017 to October 2019. Quantitative research method was used in terms of survey model by implementing a psychological test “The self-attitude test questionnaire (SA)” that assesses self-relation, differentiated by self-esteem, self-sympathy, self-interest, and expectations of self-reliance of participants. Also, during the study was used personal questionnaire “Who am I?” a variant of non-standardized self-report, approaching the projective methods of personality research. Descriptive statistics were used to analyze the answers in terms of their levels of the participants’ self-esteem and self-relation and further, since it was revealed according to the results reflect the difference in the two groups by the values obtained from these scales, the Student's t-test for independent groups was used [2] was used to reveal whether there is any correlation between the components of the scale. The obtained results can be used to interventions and training of family for counselors in order to promote women's self-esteem and self-relation.


2015 ◽  
Vol 27 (3) ◽  
pp. 275-288 ◽  
Author(s):  
Olívia Penatti Pinese ◽  
José Fernando Pinese ◽  
Kleber Del Claro

Abstract Aims: Vereda wetlands are among the most important aquatic habitats in Brazilian savannah (Cerrado) because of their association with river springs and its relevancy for biodiversity conservation. This study aimed to determine and compare the biodiversity of zooplankton in vereda lakes, differentiated by the presence or absence of aquatic macrophytes at an environmental reserve in Uberlândia, Minas Geais, Southeastern Brazil. Zooplanctonic abundance patterns and their relation with environmental parameters were also discussed and presented through multivariate statistics. Methods Twelve samples were taken at water surface, at 15-day intervals in 2006. It was observed a total richness of 75 species, including 12 genera, 29 species and one sub-species as new records for Minas Gerais State. Results Rotifers were the predominant group and Lecanidae was the most diverse family. Among cladocerans, Chydoridae showed the greatest richness and Bosminidae the highest abundance. Few adult copepods were sampled in this study, but nauplii were very frequent. Cyclopidae was the most common family among copepods and there was no record of Calanoida. Conclusions The difference in composition among the studied lakes was remarkable. The lake with macrophytes showed the greatest richness but the lowest density, and the opposite situation occurred in the other lake. This can be explained by the fact that aquatic macrophytes, as primary producers, exert a bottom-up effect on zooplankton community, sustaining a high local diversity in contrast with a low numeric abundance of these microorganisms. Therefore, this pattern may have been created by the surround heterogeneity and, at the same time, by the reduction of available minerals of the system caused by macrophyte matter fixation. Many studies on zooplankton need to be developed in palm swamp communities in order to better comprehend the biological diversity and the energy balance in different habitats for the conservation of aquatic ecosystems.


2017 ◽  
Vol 11 (3) ◽  
pp. 26-32
Author(s):  
Anna Dobrzycka ◽  
Iwona Wilk

Background: Primary menstrual pain affects approximately 45-95% of women between 20-25 years of age. A non-invasive method in reducing menstrual pain by relaxing muscle tension is a massage. It brings the structural tension to normal levels and restores correct blood flow in the pelvic region. Aim of the study: The aim of this study was to test the usefulness of a self-massage in reducing the primary menstrual pain. Materials and methods: Out of 180 female students, 34 women aged 19-30 were qualified for the study with the use of a survey. Pittsburgh Sleep Quality Index questionnaire and visual analog pain scale (VAS) were used for the assessment before and after the therapy. Women in the experimental group performed tensegrity selfmassage a few days before the onset of bleeding for two menstrual cycles. Results were analyzed using Student’s t test and one-way analysis of variance (ANOVA). Results: Applying the self-massage statistically proved to significantly reduce the perception of pain (p=0.001) and the number of days with pain (p=0.007) in the experimental group. Within this group, the difference was noted in all participants except one. In addition, a third measurement was taken in order to assess the duration of the effect. The result of the average pain and number of days of pain after the extension was higher than in the second evaluation, but significantly lower than before the experiment. The significance was in accordance with the evaluation of pain, p=0.002 and number of days p=0.03. Evaluation of the quality of sleep in the experimental group was significantly better (p = 0.04) than before treatment. Conclusions: Self-massage reduces primary menstrual pain in women and can be used as an assisted form of self-therapy. It improves the quality of sleep.


2021 ◽  
Vol 8 ◽  
Author(s):  
Annabell Moser ◽  
Iain Pheasant ◽  
William N. MacPherson ◽  
Bhavani E. Narayanaswamy ◽  
Andrew K. Sweetman

Sediment profiling imaging (SPI) is a versatile and widely used method to visually assess the quality of seafloor habitats (e.g., around fish farms and oil and gas rigs) and has been developed and used by both academics and consultancy companies over the last 50 years. Previous research has shown that inserting the flat viewport of an SPI camera into the sediment can have an impact on particle displacement pushing oxygenated surface sediments to deeper sediment depths and making anthropogenically-disturbed sediment appear healthier than they may actually be. To investigate the particle displacement that occurs when a flat plate is inserted into seafloor sediments, a testing device, termed the SPI purpose-built sediment chamber (SPI-PUSH) was designed and used in a series of experiments to quantify smearing where luminophores were used to demonstrate the extent of particle displacement caused by a flat plate being pushed into the sediment. Here, we show that the plate of the SPI-PUSH caused significant smearing, which varied with sediment type and the luminophore grain size. The mean particle smearing measured directly behind the inserted plate was 2.9 ± 1.5 cm for mud sediments with sand-like luminophores, 4.3 ± 2.5 cm for fine sand sediments with sand-like luminophores and 1.9 ± 1.1 cm for medium sand sediments with mud-like luminophores. When the mean depth of particle smearing was averaged over a larger sediment volume (11 cm3) next to the inserted plate, substantial differences were seen between the plate-insertion experiments and controls highlighting the potential extent of smearing artefacts that may be produced when a SPI camera penetrates the seafloor. This experimental data shows that future studies using the SPI camera, or any other periscope-like device (e.g., planar optodes) need to acknowledge that smearing may be significant. Furthermore, it highlights that a correction factor may need to be applied to these data (e.g., the depth of apparent redox potential discontinuity layer) to correctly interpret SPI camera images and better determine the effect of anthropogenic impacts on seafloor habitats.


2020 ◽  
Vol 1 (1) ◽  
pp. 66-71
Author(s):  
Syahril Nedi ◽  
Yolanda Manik ◽  
Elizal Elizal

The purpose of this researched was to analize the consistency of organic material and sediment fraction on estuary in dumai river. The research was with purposive sampling on four stutions. The analysis of sediment fraction in estuary in dumai river had been dominated by mud substract. The result mean size wened very fine sand, of consistency organic material is ranging 7,37 - 24,01 mg/l. The result sorting value wered poorly kurtosis value were ektremly leptokurtic, and skewness dominant value were negative. Difference of fine grafain and type of sediment on estuary in Dumai River had effect by physics and chemical factor.


Author(s):  
Larissa Chaves Cardoso FERNANDES ◽  
Patrícia Moreira RABELLO ◽  
Bianca Marques SANTIAGO ◽  
Marcus Vitor Diniz de CARVALHO ◽  
Manoel Raimundo de SENA JÚNIOR ◽  
...  

ABSTRACT Objetive To determine the percentage of correctness of the Orbital Index (OI) for estimation of sex, ancestry and age in Brazilian skulls. Methods Cross-sectional study of 183 human dry skulls from the southeastern Brazil. A total of 100 skeletons were males and 83 females; of which 36 were aged up to 39 years, 60 aged between 40 and 59 years, and 87 aged 60 years or older. As for ancestry, 103 were from white, 51 mixed race, and 29 black individuals. The OI was calculate by the formula = height/width x 100. The data were submitted to Student’s t test, F (ANOVA), Tukey and Kruskal Wallis tests as well as to discriminant analysis, with a 5% significance level. Results The sample was characterized as mesoseme, with a mean age of 56.62 (±19.97) years. No significant difference was observed (p=0.511) between the OI in females (right: 86.43 ± 6.58 and left: 86.70 ± 5.93) and males (right: 85.78 ± 6.69 and left: 86.37 ± 6.20). There were no significant differences between age, ancestry and the variables analyzed (p>0.05). The right and left orbital widths were significantly dimorphic between sexes (p<0.001). The percentage of correctness of the method for estimation of sex, age and ancestry was found to be 65.6%, 43.7%, and 43.6%, respectively. Conclusions The OI is not an appropriate method for estimation of sex, ancestry and estimation of age in this Brazilian sample. The methodology should be expanded to other population groups so that it can be improved.


Abstract.—Spiny dogfish <em>Squalus acanthias </em>have been an important component of the Strait of Georgia fisheries from the late 1800s to the late 1940s, when the fishery collapsed owing to overfishing and changes in market demand. The stock population levels have sustained a commercial fishery of approximately 2,000 metric tons since 1978. Recent concerns regarding the status of dogfish stocks worldwide have reprioritized the status assessment of dogfish in British Columbia. Longline research surveys were conducted for dogfish in the Strait of Georgia in 1986, 1989, and 2005. Additional sources of information are catch and effort data collected through logbook records from the commercial longline fishery. Recent improvements in gear configuration resulted in a switch in the mid-1990s from traditional J hooks to circle hooks, which makes direct comparison of catch rates difficult. In November 2004 a calibration experiment using J hooks and circle hooks demonstrated that, overall, spiny dogfish catch per unit effort (CPUE) for circle-hook gear was 1.6–1.7 times higher than that for J-hook gear. After applying this conversion to the commercial longline CPUE data available for 1980–1984 and 2000–2004, no significant trend in catch rate over time was detected. The catch rate observed in the longline research survey actually increased in 2005 compared to 1986 and 1989. In both fisheries and research data, the proportion of smaller spiny dogfish in the size distribution has increased, reducing the overall mean size. The decline in mean size is probably due to an increase in recruitment of juvenile fish. However, caution in management of this stock is warranted given that the current commercial fishery is now landing a large proportion (estimated 80%) of immature fish. Increased fishing pressure on juveniles could have implications for the abundance of mature fish in upcoming decades.


2019 ◽  
Vol 218 (9) ◽  
pp. 2841-2853 ◽  
Author(s):  
Claire Strothman ◽  
Veronica Farmer ◽  
Göker Arpağ ◽  
Nicole Rodgers ◽  
Marija Podolski ◽  
...  

Dynamic organization of microtubule minus ends is vital for the formation and maintenance of acentrosomal microtubule arrays. In vitro, both microtubule ends switch between phases of assembly and disassembly, a behavior called dynamic instability. Although minus ends grow slower, their lifetimes are similar to those of plus ends. The mechanisms underlying these distinct dynamics remain unknown. Here, we use an in vitro reconstitution approach to investigate minus-end dynamics. We find that minus-end lifetimes are not defined by the mean size of the protective GTP-tubulin cap. Rather, we conclude that the distinct tubulin off-rate is the primary determinant of the difference between plus- and minus-end dynamics. Further, our results show that the minus-end–directed kinesin-14 HSET/KIFC1 suppresses tubulin off-rate to specifically suppress minus-end catastrophe. HSET maintains its protective minus-end activity even when challenged by a known microtubule depolymerase, kinesin-13 MCAK. Our results provide novel insight into the mechanisms of minus-end dynamics, essential for our understanding of microtubule minus-end regulation in cells.


2018 ◽  
Vol 32 (12n13) ◽  
pp. 1840032
Author(s):  
Lijuan Qian ◽  
Shaobo Song ◽  
Lisha Jiang ◽  
Xiaolu Li ◽  
Jianzhong Lin

The breakup of viscoelastic liquid films are investigated experimentally and analytically. The breakup phenomena of viscoelastic liquid film are recorded by the time resolved high speed camera. Video images reveal the difference behavior of liquid bubble breakup for Newtonian and viscoelastic liquid. For the Newtonian liquid, cylindrical ligaments are stretched into droplets with large distributions of drop size. For the viscoelastic liquid, the pinch-off point is located on the liquid connections to the nozzle and finally the main part of the ligament no longer elongates. Furthermore, a dispersion relation based on the stability analysis is involved to predict the ligament length and drop mean size after breakup for liquid film. The calculated ligament length is validated by the measured drop mean size at higher air-to-liquid mass flow ratio.


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