scholarly journals Habitat use and abundance of goliath grouper Epinephelus itajara in Brazil: a participative survey

2014 ◽  
Vol 12 (4) ◽  
pp. 803-810 ◽  
Author(s):  
Vinicius J. Giglio ◽  
Johnatas Adelir-Alves ◽  
Leopoldo C. Gerhardinger ◽  
Fabiano C. Grecco ◽  
Felippe A. Daros ◽  
...  

Developing survey strategies for threatened species is often limited by access to sufficient individuals to acquire information needed to design appropriate conservation measures. The goliath grouper (Epinephelus itajara) is a large reef fish, globally classified as critically endangered. In Brazil, fishing has been prohibited since 2002. Herein we investigated habitat use and abundance of E. itajara in Brazil drawn from a participative survey, which engaged volunteer divers in data-collection. A total of 188 reports were recorded between 2005 to 2011 throughout 13 Brazilian states. Our results revealed that habitat type influenced the relationship between total length and depth of occurrence of E. itajara. We observed a significant difference between habitats, artificial presented a nonlinear and natural an asymptotic relationship. This study underscores the importance of developing conservation measures addressing specific habitats and locations to enhance population recovery. Artificial structures (shipwrecks and manmade reefs) are critical habitats that must be considered as highly sensitive areas to E. itajara strategic conservation policies. We suggest the creation and implementation of marine protected areas, as key strategies for E. itajaraconservation, especially for artificial habitats and aggregation sites.

2010 ◽  
Vol 88 (11) ◽  
pp. 1052-1062 ◽  
Author(s):  
M. Pellerin ◽  
C. Calenge ◽  
S. Saïd ◽  
J.- M. Gaillard ◽  
H. Fritz ◽  
...  

In most previous studies of habitat selection, the use of a given habitat type is assumed to be directly proportional to its availability. However, the use and (or) the selection of a given habitat may be conditional on the availability of that habitat. We aim here to (i) identify the environmental variables involved in habitat selection, (ii) identify classes of individuals with similar patterns of habitat selection, and (iii) assess whether habitat use changes with changing availability of habitat types, within monthly home ranges of female western roe deer ( Capreolus capreolus (L., 1758)). We found that some females adjust their habitat use according to the distribution of resources within habitats. Females with similar home ranges in terms of resource quantity and quality showed similar patterns of habitat selection. Differences in habitat use between 2 years with contrasting resource availability showed that temporal changes of environmental conditions influenced the pattern of habitat selection by female roe deer. Habitat selection also differed between periods of the life cycle likely because of contrasted energy requirements. This study shows that the relationship between habitat use by herbivores and habitat availability is nonproportional, and that the availability of resources influences use mostly at intermediate values.


2004 ◽  
Vol 55 (1) ◽  
pp. 105 ◽  
Author(s):  
A. R. Thompson

To elucidate factors that affect patterns of habitat use by a goby, Ctenogobiops feroculus, which interacts mutualistically with an alpheid shrimp, Alpheus djeddensis, goby density and habitat type were surveyed along the north shore of Moorea, French Polynesia. Although linear and quadratic multiple regression models both described the relationship between goby density and habitat as being statistically significant, more than twice the variation was accounted for by the quadratic model compared with the linear model. Further evaluation using univariate scatter plots confirmed that goby density correlated non-linearly with habitat as maximal goby density occurred in locations with approximately 71% sand and 29% rubble. Next, an aquarium-based, habitat choice experiment demonstrated that shrimp prefer to burrow in sand–rubble compared with pure sand, and that shrimp are unable to build tunnels in pure sand because burrows collapse in this substrate. This research shows that habitat choice by one organism (e.g. a shrimp) can, because of positive interactions, affect the distribution of another species (e.g. a goby). In addition, it highlights the importance of assessing non-linear relationships in studies of habitat use and, when appropriate, using statistical methods that do not rely on linear assumptions.


2000 ◽  
Vol 39 (01) ◽  
pp. 10-15 ◽  
Author(s):  
S. P. Müller ◽  
Ch. Reiners ◽  
A. Bockisch ◽  
Katja Brandt-Mainz

Summary Aim: Tumor scintigraphy with 201-TICI is an established diagnostic method in the follow-up of differentiated thyroid cancer. We investigated the relationship between thyroglobulin (Tg) level and tumor detectability. Subject and methods: We analyzed the scans of 122 patients (66 patients with proven tumor). The patient population was divided into groups with Tg above (N = 33) and below (N = 33) 5 ng/ml under TSH suppression or above (N = 33) and below (N = 33) 50 ng/ml under TSH stimulation. Tumor detectability was compared by ROC-analysis (True-Positive-Fraction test, specificity 90%). Results: There was no significant difference (sensitivity 75% versus 64%; p = 0.55) for patients above and below 5 ng/ml under TSH suppression and a just significant difference (sensitivity 80% versus 58%; p = 0.04) for patients above and below 50 ng/ml under TSH stimulation. In 18 patients from our sample with tumor, Tg under TSH suppression was negative, but 201-TICI-scan was able to detect tumor in 12 patients. Conclusion: Our results demonstrate only a moderate dependence of tumor detectability on Tg level, probably without significant clinical relevance. Even in patients with slight Tg elevation 201-TICI scintigraphy is justified.


1989 ◽  
Vol 121 (4) ◽  
pp. 513-519 ◽  
Author(s):  
Hiroshi Tomita ◽  
Masamichi Ogawa ◽  
Takashi Kamijo ◽  
Osamu Mori ◽  
Eiji Ishikawa ◽  
...  

Abstract. GH values were determined by a highly sensitive sandwich enzyme immunoassay in the 1st morning and/or 24-h accumulated urine samples in 94 children (short stature 70, including 14 with complete GH deficiency, 9 with partial GH deficiency, and 47 with GH-normal short stature; Turner's syndrome, 10, and simple obesity, 14). GH values were also determined in the 2nd to 4th urine samples taken on the same day together with the 1st morning urine in 5 of them. GH values in the 1st morning urine correlated significantly with those of the 24-h urine and with serum peak and mean GH values during nocturnal sleep as a physiological GH secretion test. The 2nd to 4th urines had lower GH concentrations than the 1st morning urine. The GH value of the 1st morning urine in complete GH deficiency was significantly lower than those in GH-normal short stature, partial GH deficiency and Turner's syndrome. However, no significant difference was detected in urinary GH values between complete GH deficiency and simple obesity. We conclude that 1st morning urinary GH estimation may be useful for differentiation of complete GH deficiency from other causes of short stature, but may be difficult for the distinction between complete GH deficiency and obesity with normal GH secretory ability.


Author(s):  
Ma. Dulce C. Guillena

Gonado-somatic index and fecundity are tools for measuring the sexual maturity and ability of animals to reproduce.  This study investigates the reproduction of Trichiurus lepturus. Specifically, this aimed to determine the sex ratio, the GSI, the relationship between fecundity and total length, fecundity and total weight, fecundity and ovary weight. The Descriptive Method of research was used.  Percentage and chi-square was utilized in determining the percentage of occurrence and sex ratio respectively.   Pearson r Product Moment Coefficient of Correlation was used to determine the relationships of the parameters. The study revealed that females outnumbered males and the sex ratio for different month showed significant difference.  Spawning season was observed to occur in November and December as revealed in its GSI values and it synchronized with the full and new moon phases.  Fecundity is positively correlated with body weight, body size, and ovary weight where ovary weight is observed to be the best index for fecundity.  The results of this study could be used further for formal stock assessment of cutlassfish fishery.


Agrometeoros ◽  
2018 ◽  
Vol 26 (1) ◽  
Author(s):  
Ronaldo Matzenauer ◽  
Bernadete Radin ◽  
Alberto Cargnelutti Filho

O objetivo deste trabalho foi avaliar a relação entre o fenômeno El Niño Oscilação Sul - ENOS e o rendimento de grãos de soja e de milho no Rio Grande do Sul e verificar a hipótese de que os eventos El Niño são favoráveis e os eventos La Niña são prejudiciais ao rendimento de grãos das culturas. Foram utilizados dados de rendimento de grãos dos anos agrícolas de 1974/75 a 2016/17, e relacionados com as ocorrências de eventos ENOS. Foram analisados os dados de rendimento observados na colheita e os dados estimados com a remoção da tendência tecnológica. Os resultados mostraram que não houve diferença significativa do rendimento médio de grãos de soja e de milho na comparação entre os eventos ENOS. Palavras-chave: El Niño, La Niña, safras agrícolas. Abstract – The objective of this work was to evaluate the relationship between the El Niño Southern Oscillation (ENSO) phenomenon with the grain yield of soybean and maize in Rio Grande do Sul state, Brazil and to verify the hypothesis that the El Niño events are favorable and the La Niña events are harmful to the culture’s grain yields. Were used data from the agricultural years of 1974/75 to 2016/17, and related to the occurrence of ENOS events. We analyzed income data observed at harvest and estimated data with technological tendency was removed. The results showed that there was no significant difference in the average yield of soybeans and corn in the comparison between events.


2019 ◽  
Author(s):  
Siddharth Garg

Objective: The aim of this paper was to examine the relationship between income, subjective wellbeing, and culture among people from a higher socio-economic class across the world. Rationale: Ed Diener proposed the law of diminishing marginal utility as an explanation for differences in subjective wellbeing among different income groups across different countries (Diener, Ng, & Tov, Balance in life and declining marginal utility of diverse resources, 2009). Thus, people with higher incomes would experience less subjective wellbeing due to income, and culture should emerge as a significant predictor. Method: Data from this study came from another study (https://siddharthgargblog.wordpress.com/2019/07/14/love-for-money/). I used an online survey to collect data on annual income in US dollars, subjective wellbeing (WHO-5), and country of residence (Indicator of Culture). 96 responses (Indians = 24, Foreigners = 72) were entered in IBM SPSS and a regression analysis was conducted. The raw dataset used in this study can be found at https://doi.org/10.6084/m9.figshare.8869040.v1Results: ANOVA showed a significant difference (p < 0.05) between Indians and foreigners on levels of subjective wellbeing. Linear regression shows the regression coefficient of culture to be significant (Beta = -.254, p = .014) but the regression coefficient of income was not found to be significant. The overall model was found to explain 8.2% of the variance in wellbeing.Conclusion: The sample of this study is too small to make any kind of generalization; it does lend a little bit of support to the idea of diminishing marginal utility of income on subjective wellbeing and provides a rationale for further research.


2015 ◽  
Vol 72 (2) ◽  
pp. 123-131 ◽  
Author(s):  
Marko Igic ◽  
Nebojsa Krunic ◽  
Ljiljana Aleksov ◽  
Milena Kostic ◽  
Aleksandra Igic ◽  
...  

Background/Aim. The vertical dimension of occlusion is a very important parameter for proper reconstruction of the relationship between the jaws. The literature describes many methods for its finding, from the simple, easily applicable clinically, to quite complicated, with the use of one or more devices for determination. The aim of this study was to examine the possibility of determining the vertical dimension of occlusion using the vocals ?O? and ?E? with the control of values o btained by applying cognitive functions. Methods. This investigation was performed with the two groups of patients. The first group consisted of 50 females and 50 males, aged 18 to 30 years. In this group the distance between the reference points (on top of the nose and chin) was measured in the position of the mandible in the vertical dimension of occlusion, the vertical dimension at rest and the pronunciation of the words ?OLO? and ?ELE?. Checking the correctness of the particular value for the word ?OLO? was also performed by the phonetic method with the application of cognitive exercises when the patients counted from 89 to 80. The obtained difference in the average values i n determining the vertical dimension of occlusion and the ?OLO? and ?ELE? in the first group was used as the reference for determining the vertical dimension of occlusion in the second group of patients. The second group comprised of 31 edentulous persons (14 females and 17 males), aged from 54 to 85 years who had been made a complete denture. Results. The average value obtained for the vertical dimension of rest for the entire sample was 2.16 mm, for the word ?OLO? for the entire sample was 5.51 mm and for the word ?ELE? for the entire sample was 7.47 mm. There was no statistically significant difference between the genders for the value of the vertical dimension at rest, ?ELE? and ?OLO?. There was a statistically significant difference between the values f or the vertical dimension at rest, ?OLO? and ?ELE? for both genders. There was a statistically significant correlation between the value for the vertical dimension at rest, ?OLO? and ?ELE?, for both groups of subjects. Conclusion. Determining the vertical dimension of occlusion requires 5.5 mm subtraction from the position of the mandible in pronunciation of the word ?OLO? or 7.5 mm in pronunciation of the word ?ELE?.


2021 ◽  
pp. 1-8
Author(s):  
Mustafa Avcu ◽  
Mehmet Metin ◽  
Raşit Kılıç ◽  
Muhammed Alpaslan

Background: In this study, optic coherence tomography (OCT) examination was performed to check whether there was any interaction between ophthalmic axonal structures in unilateral tinnitus patients, and the relationship between optic nerve thickness and cochlear nerve thickness was evaluated. Objective: The aim of the study was to evaluate the relatioship between hearing loss, tinnitus, and nerve thicknesses. Study Design: Prospective study. Setting: Tertiary referral university hospital. Patients: The study included 88 patients with unilateral tinnitus, for which no organic cause could be found in physical examination, psychiatric evaluation, or with imaging methods. Study groups were formed of the tinnitus side and control groups were formed of the healthy side as follows: Group 1 (Non-tinnitus side normal hearing values – n = 30), Group 2 (non-tinnitus side minimal hearing loss – n = 27), Group 3 (non-tinnitus side moderate hearing loss – n = 31), Group 4 (tinnitus side normal hearing values – n = 25), Group 5 (tinnitus side minimal hearing loss – n = 25), and Group 6 (tinnitus side moderate hearing loss – n = 38). Intervention: Retinal nerve fiber layer (RNFL) thickness was evaluated with OCT, and the cochlear nerve cross-sectional area was evaluated with MRI. Main Outcome Measures: RNFL measurements were taken with OCT from the subfoveal area (RNFL-SF) and 1.5 mm temporal to the fovea (RNFL-T µm) and nasal (RNFL-N µm) sectors. On MRI, 3 measurements were taken along the nerve from the cerebellopontine angle as far as the internal auditory canal, and the mean value of these 3 measurements was calculated. Results: When the groups were evaluated in respect of cochlear nerve thickness, a significant difference was seen between Group 1 and both the groups with hearing loss and the tinnitus groups. In the subgroup analysis, a statistically significant difference was determined between Group 1 and Groups 3, 4, 5, and 6 (p = 0.013, p = 0.003, p < 0.001, and p < 0.001, respectively). When the groups were evaluated in respect of the RNFL-SF (µm), RNFL-T (µm), and RNFL-N (µm) values, the differences were determined to be statistically significant (p < 0.001 for all). In the correlation analysis, a negative correlation was determined between hearing loss and cochlear nerve diameter (r: −0.184, p = 0.014), and RNFL-N (r: −0.272, p < 0.001) and between tinnitus and cochlear nerve diameter (r: −0.536, p < 0.001), and RNFL-T (r: −0.222, p < 0.009). Conclusion: The study results clearly showed a relationship between cochlear nerve fiber thickness and hearing loss and the severity of tinnitus in cases with unilateral tinnitus and that there could be neurodegenerative factors in the disease etiology. A similar relationship seen with the RNFL supports the study hypothesis.


2021 ◽  
pp. 1-7
Author(s):  
Emre Erdem ◽  
Ahmet Karatas ◽  
Tevfik Ecder

<b><i>Introduction:</i></b> The effect of high serum ferritin levels on long-term mortality in hemodialysis patients is unknown. The relationship between serum ferritin levels and 5-year all-cause mortality in hemodialysis patients was investigated in this study. <b><i>Methods:</i></b> A total of 173 prevalent hemodialysis patients were included in this study. The patients were followed for up to 5 years and divided into 3 groups according to time-averaged serum ferritin levels (group 1: serum ferritin &#x3c;800 ng/mL, group 2: serum ferritin 800–1,500 ng/mL, and group 3: serum ferritin &#x3e;1,500 ng/mL). Along with the serum ferritin levels, other clinical and laboratory variables that may affect mortality were also included in the Cox proportional-hazards regression analysis. <b><i>Results:</i></b> Eighty-one (47%) patients died during the 5-year follow-up period. The median follow-up time was 38 (17.5–60) months. The 5-year survival rates of groups 1, 2, and 3 were 44, 64, and 27%, respectively. In group 3, the survival was lower than in groups 1 and 2 (log-rank test, <i>p</i> = 0.002). In group 1, the mortality was significantly lower than in group 3 (HR [95% CI]: 0.16 [0.05–0.49]; <i>p</i> = 0.001). In group 2, the mortality was also lower than in group 3 (HR [95% CI]: 0.32 [0.12–0.88]; <i>p</i> = 0.026). No significant difference in mortality between groups 1 and 2 was found (HR [95% CI]: 0.49 [0.23–1.04]; <i>p</i> = 0.063). <b><i>Conclusion:</i></b> Time-averaged serum ferritin levels &#x3e;1,500 ng/mL in hemodialysis patients are associated with an increased 5-year all-cause mortality risk.


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