scholarly journals Commercial catches and discards composition in the central Tyrrhenian Sea: a multispecies quantitative and qualitative analysis from shallow and deep bottom trawling

2021 ◽  
Vol 22 (3) ◽  
pp. 521
Author(s):  
FRANCESCO TIRALONGO ◽  
EMANUELE MANCINI ◽  
DANIELE VENTURA ◽  
STEPHANIE DE MALERBE ◽  
FRANCESCO PALADINI DE MENDOZA ◽  
...  
Keyword(s):  
Benthic Communities ◽  
Human Consumption ◽  
Tyrrhenian Sea ◽  
Target Species ◽  
Catch Per Unit Effort ◽  
Management Measures ◽  
Starting Point ◽  
The Mean ◽  
Negative Impacts ◽  
Trawl Fisheries

In the Mediterranean Sea, the catch of bottom trawl fisheries is composed of a complex mix of fish and invertebrates with a considerable amount of discards. Seasonal composition of catches and discards of bottom trawls operating at different depths in the central Tyrrhenian Sea were investigated from October 2014 to October 2015. The mean total catch per unit effort (CPUE) ranged between 30.93±8.43 and 27.52±9.88 kg/h in shallow and deep fishing grounds, respectively. The discarded fraction of the catch was 39.9 % in shallow and 43.3% in deep fishing grounds. The mean CPUE of commercial target species were similar in shallow and deep trawling (10.81+5.82 vs 8.92±3.16 kg/h). The commercial bycatch was lower in shallow (6.66±1.25 kg/h) than in deep grounds (8.24±2.91 kg/h), whilst the discards were lower in deep (10.43±5.14 kg/h) than shallow grounds (13.43±5.29 kg/h). Overall, 246 species were caught during fishing operations, out of which 209 were included in discards. The number of species recorded in shallow grounds (199 caught species with 166 discarded) was higher than that recorded in deep grounds (116 caught species with 102 discarded). Fish were the most represented taxa in the shallow discards, followed by echinoderms; crustaceans, and were the main discarded taxa in deep water. Depth was the main factor affecting both commercial catches and discards composition, whereas the season affected the CPUE of main target species only. The results confirmed that discards were higher in shallow than in deep trawling, suggesting that the latter is more efficient than the former in catching fishery resources for human consumption. Understanding the factors that affect discarding is the starting point for adopting management measures to mitigate negative impacts of trawl fisheries on marine resources and benthic communities.

Descriptive statistics

2017 ◽  
Author(s):  
Andrew Gelman ◽  
Deborah Nolan
Keyword(s):  
Descriptive Statistics ◽  
Metabolic Rates ◽  
World Record ◽  
Linear Combinations ◽  
Record Times ◽  
Starting Point ◽  
Statistics Course ◽  
Scatter Plots ◽  
Economic Indexes ◽  
The Mean

Descriptive statistics is the typical starting point for a statistics course, and it can be tricky to teach because the material is more difficult than it first appears. The activities in this chapter focus more on the topics of data displays and transformations, rather than the mean, median, and standard deviation, which are covered easily in a textbook and on homework assignments. Specific topics include: distributions and handedness scores; extrapolation of time series and world record times for the mile run; linear combinations and economic indexes; scatter plots and exam scores; and logarithmic transformations and metabolic rates.

scholarly journals Modeling of Lake Malombe Annual Fish Landings and Catch per Unit Effort (CPUE)

Forecasting ◽  
2021 ◽  
Vol 3 (1) ◽  
pp. 39-55
Author(s):  
Rodgers Makwinja ◽  
Seyoum Mengistou ◽  
Emmanuel Kaunda ◽  
Tena Alemiew ◽  
Titus Bandulo Phiri ◽  
...  
Keyword(s):  
Time Series ◽  
Information Criterion ◽  
Coefficient Of Determination ◽  
Series Data ◽  
Efficiency Coefficient ◽  
Arima Models ◽  
Catch Per Unit Effort ◽  
Annual Fish ◽  
Unit Effort ◽  
The Mean

Forecasting, using time series data, has become the most relevant and effective tool for fisheries stock assessment. Autoregressive integrated moving average (ARIMA) modeling has been commonly used to predict the general trend for fish landings with increased reliability and precision. In this paper, ARIMA models were applied to predict Lake Malombe annual fish landings and catch per unit effort (CPUE). The annual fish landings and CPUE trends were first observed and both were non-stationary. The first-order differencing was applied to transform the non-stationary data into stationary. Autocorrelation functions (AC), partial autocorrelation function (PAC), Akaike information criterion (AIC), Bayesian information criterion (BIC), square root of the mean square error (RMSE), the mean absolute error (MAE), percentage standard error of prediction (SEP), average relative variance (ARV), Gaussian maximum likelihood estimation (GMLE) algorithm, efficiency coefficient (E2), coefficient of determination (R2), and persistent index (PI) were estimated, which led to the identification and construction of ARIMA models, suitable in explaining the time series and forecasting. According to the measures of forecasting accuracy, the best forecasting models for fish landings and CPUE were ARIMA (0,1,1) and ARIMA (0,1,0). These models had the lowest values AIC, BIC, RMSE, MAE, SEP, ARV. The models further displayed the highest values of GMLE, PI, R2, and E2. The “auto. arima ()” command in R version 3.6.3 further displayed ARIMA (0,1,1) and ARIMA (0,1,0) as the best. The selected models satisfactorily forecasted the fish landings of 2725.243 metric tons and CPUE of 0.097 kg/h by 2024.

scholarly journals Faecal bacteria in Perna perna (Linnaeus, 1758) (Mollusca: Bivalvia) for biomonitoring coastal waters and seafood quality

2010 ◽  
Vol 58 (spe3) ◽  
pp. 29-35 ◽  
Author(s):  
Diego Igawa Martinez ◽  
Ana Júlia Fernandes Cardoso de Oliveira
Keyword(s):  
Coastal Waters ◽  
Microbiological Quality ◽  
Perna Perna ◽  
Clearance Rates ◽  
Bacterial Concentration ◽  
Allometric Relations ◽  
The Mean ◽  
Negative Impacts ◽  
Faecal Bacteria

Urban development in coastal areas is intense and leads to the increase of sewage outfall and other negative impacts as consequences. Thus, stringent regulations establishing limits to the microbiological contamination of water and seafood are needed. The objective of this study is to evaluate the usefulness of Enterococci and Thermotolerant Coliform densities in the flesh of mussels Perna perna as an alternative tool for monitoring the microbiological quality of coastal waters. The study also considers allometric relations applied to clearance rates to understand rates of bacterial concentration. Bacterial loads obtained in mussels' flesh were from 50 to 4,300 times greater than in the water sampled in the vicinity of the mussels and some were considered inappropriate for consumption even when the water presented no restrictions. The mean clearance rate obtained for Enterococci retention was 317.7 ml h-1 and this rate (CR) is related to the mussels' size (L) by the equation CR = 28.3229L1.6421. The results showed that bacterial densities in the mussels' tissues may reflect chronic contamination of the environment and that clearance rates are important for taking the best decision in situations where, for example, it is desired to introduce mussels for aquaculture and the evaluation of the water concerned is required.

Fish and invertebrate by-catch in the crab pot fishery in the Isle of Man, Irish Sea

2017 ◽  
Vol 98 (8) ◽  
pp. 2099-2111
Author(s):  
Fikret Öndes ◽  
Michel J. Kaiser ◽  
Lee G. Murray
Keyword(s):  
Irish Sea ◽  
Target Species ◽  
Catch Per Unit Effort ◽  
Isle Of Man ◽  
Ecosystem Effects ◽  
By Catch ◽  
Catch Rates ◽  
Taxonomic Groups ◽  
Catch Composition ◽  
Autumn And Winter

Baited trap or pot fisheries are considered to have relatively few wider ecosystem effects on the marine environment, particularly when compared with towed mobile fishing gear. However, this assumption is rarely tested in the field. This study aimed to determine the composition of non-target species that occur in crustacean pots and to assess spatial and temporal differences in catches in the waters around the Isle of Man, Irish Sea. The data were collected using fishery independent surveys and a questionnaire study. Based on fishery independent surveys, a total of five taxonomic groups and 43 species occurred as by-catch. The dominant by-catch species was velvet crab Necora puber. The by-catch per unit effort (BPUE) for all of the non-target species was low particularly in comparison to towed bottom gear fisheries around the Isle of Man. BPUE of species composition varied considerably between different locations around the Isle of Man. The results of both the fishery independent and questionnaire data suggested that the by-catch rates varied with season with peak BPUE occurring in spring which then declined into autumn and winter. By-catch composition did not decrease significantly with an increasing target species catch. Overall, by-catch was low relative to target species catch which may be partially attributable to the use of escape panels in pot fisheries in the Isle of Man.

Evaluation of heavy metals content in the canned/packed fruit juices from local and imported origin in Lahore, Pakistan

2021 ◽  
Author(s):  
Nazeefa Fatima ◽  
Munazza Khan ◽  
Muhammad Shuaib Kabeer
Keyword(s):  
Heavy Metals ◽  
Atomic Absorption ◽  
Fruit Juices ◽  
Human Consumption ◽  
Acid Digestion ◽  
Digestion Method ◽  
Mean Values ◽  
Nutritive Values ◽  
The Mean ◽  
Mean Concentration

This study was conducted to determine the mean concentration of heavy metals such as lead (Pb), copper (Cu), zinc (Zn), chromium (Cr), manganese (Mn), nickel (Ni), selenium (Se), magnesium (Mg), and iron (Fe) in canned/packed fruits juices, collected from various stores in Lahore in a period of three months. These juices were categorized into four groups; local packed and canned and also imported packed and canned products. Every group consisted of ten samples. By using the di-acid digestion method, the collected samples were digested and analyzed under Atomic Absorption Spectrophotometer (AAS). The results indicated that the mean values of 7 out of 9 tested heavy metals including Pb, Mg, Ni, Fe, Cr, Se and Mn were above permissible limits (set by WHO) in all four understudy groups. Therefore, it was concluded that commercially available fruit juices are not all safe according to their heavy metals content for the human consumption despite their nutritive values.

scholarly journals Quality assessment of Zeus faber (Peter’s fish) ovaries regularly commercialized for human consumption

2018 ◽  
Vol 7 (1) ◽  
Author(s):  
Filippo Giarratana ◽  
Graziella Ziino ◽  
Valerio D'Andrea ◽  
Antonio Panebianco ◽  
Alessandro Giuffrida
Keyword(s):  
Quality Assessment ◽  
Mean Value ◽  
Raw Material ◽  
Human Consumption ◽  
Salmonella Spp ◽  
The Mean ◽  
Fresh Products ◽  
Vibrio Spp ◽  
Zeus Faber

n the last few years, the consumption of fish eggs has increased rapidly, finding widespread use also in mass catering. This increase has involved also those of the Peter’s fish (Zeus faber). Females of this species, by their reproductive characteristics, have highly developed gonads in different periods of the year, making the raw material easy to find. The aim of the present study was to perform a quality assessment of Zeus faber ovaries regularly commercialized for human consumption. A total number of 34 samples, divided in fresh (11) and frozen (23), were processed for microbiological characterization, parasitological and histological evaluations. Fresh and frozen samples have significant (P<0.01) differences in total bacterial charge, with values of 4.75±0.5 Log CFU/g and 3.65±0.7 Log CFU/g respectively. The mean value of Enterobacteriaceae was 2.58±0.7 Log CFU/g in fresh products, while 52.17% (12) of frozen samples reported loads of <1 Log CFU/g. No Salmonella spp. and Listeria monocytogenes were found. Aeromonas spp. was detected in two frozen sample (with loads of 2.2 and <1 Log CFU/g) and in 5 fresh ovaries with value ranged from 1.70 to 3.48 Log CFU/g. Vibrio spp. was found in 4 (36.36%) and 3 (13.04%) of fresh and frozen samples respectively, with loads always <1 Log CFU/g. All 31 Vibrio strains isolated, were identified as Vibrio alginolyticus, and 61.29% (19) of them was positive for the ToxRS factor and 6.45% (2) for ToxR. The 47.06% (16) of total samples showed infestations by larvae of Anisakis Type 1 in the serous and inside the ovary. In this last case, histologically it was found to be free larvae. This study attested satisfactory hygiene conditions for Zeus faber ovaries currently marked for human consumption. The presence of potentially pathogenic strains of V. alginolyticus and Aeromonas spp., but above all the frequent infestation by Anisakis larvae, represent a potentially hazard for the consumer.

Statistical Analyses of High Cycle Fatigue French Data for Austenitic SS

2014 ◽  
Author(s):  
Géraud Blatman ◽  
Thomas Métais ◽  
Jean-Christophe Le Roux ◽  
Simon Cambier
Keyword(s):  
Strain Amplitude ◽  
High Cycle Fatigue ◽  
Experimental Testing ◽  
Austenitic Stainless Steels ◽  
Fatigue Curve ◽  
Statistical Analyses ◽  
Starting Point ◽  
The Mean ◽  
Number Of Cycles ◽  
Selection Of

In the 2009 version of the ASME BPV Code, a set of new design fatigue curves were proposed to cover the various steels of the code. These changes occurred in the wake of publications [1] showing that the mean air curve used to build the former ASME fatigue curve did not always represent accurately laboratory results. The starting point for the methodology to build the design curve is the mean air curve obtained through laboratory testing: coefficients are then applied to the mean air curve in order to bridge the gap between experimental testing and reactor conditions. These coefficients on the number of cycles and on the strain amplitude are equal to 12 and 2 respectively in the 2009 ASME BPV code, using the mean air curve proposal from NUREG/CR-6909 [1]. Internationally, with the same mean air curve, other proposals have emerged and especially in France [2]-[3] where a consensus seems to be reached on the reduction of the coefficient on strain amplitude. This paper provides statistical analyses of the experimental data obtained in France at high-cycle for austenitic stainless steels. It enables to bring arguments for the selection of a coefficient on strain amplitude in the French RCC-M code, where less scatter on the data is witnessed due to fewer material grades.

Workplace Fatigue Within Summer Camp: Perspectives From Camp Health Care Providers and Directors

2019 ◽  
Vol 43 (1) ◽  
pp. 71-87
Author(s):  
Alexsandra Dubin ◽  
Barry A. Garst ◽  
Tracey Gaslin ◽  
Beth E. Schultz
Keyword(s):  
Health Care ◽  
Health Care Providers ◽  
Employee Performance ◽  
Summer Camps ◽  
Future Research ◽  
Care Providers ◽  
Frontline Staff ◽  
Analysis Process ◽  
Starting Point ◽  
Negative Impacts

Background: Summer camps engage millions of youth in enrichment opportunities during the summertime while employing a substantial young adult workforce to provide high-quality programs and services to camp participants. Workplace fatigue has been implicated in camp-related injury and illness events, yet few studies have targeted fatigue among camp employees. Purpose: This study aimed to better understand how fatigue impacted employee performance as well as strategies for reducing the negative impacts of fatigue within camp settings. Methodology/Approach: Focus groups were conducted with camp health care providers and directors, and their responses were analyzed using directed content analysis. The analysis process was guided by sensitizing concepts from the literature. Findings/Conclusions: Emergent themes suggested that camp-related fatigue is conceptualized as a construct of time, types, and causes; is a distinct experience leading to setting-specific outcomes; is managed using administrative and peer supports; and is sometimes perceived in positive ways. Implications: This exploratory study highlighted the unique challenges associated with working in a camp setting and the potential development of fatigue as a starting point informing future research. It suggests that future research should include a broader study population, including frontline staff, as well as possible quantitative measures.

scholarly journals Randomized response surface pathway design with skewed starting point and stochastic dose window

2020 ◽  
Vol 7 (1) ◽  
pp. 18
Author(s):  
Trond Holand ◽  
Øystein Evensen ◽  
Sagita Dewi ◽  
Stig Larsen
Keyword(s):  
Atlantic Salmon ◽  
Response Surface ◽  
Initial Dose ◽  
Salt Water ◽  
Lower Boundary ◽  
Response Variable ◽  
Ct Value ◽  
Starting Point ◽  
Starting Dose ◽  
The Mean

<p class="abstract"><strong>Background:</strong> The aim was to introduce response surface pathway (RSP)-design with skewed starting value and stochastic dose-window to estimate optimal efficacy dose (OED) of BP-C2 after IL-1β stimulation in Atlantic salmon.</p><p class="abstract"><strong>Methods:</strong> 54 healthy smolt of Atlantic salmon between 50 and 100 g before habituated to salt water were included. The study was conducted as a one-dimensional, randomized between-patient three-level RSP designed trial with one interventional- and one response variable and odd outcomes. The interventional variable was intraperitoneal injected BPC2 with skewed starting dose of 0.10 mg/100 g related to the initial dose-window &lt;0.02-0.5 mg/100 g. The response variable was the Ct-value of mRNA IL-1β expression 24 hours after injection.</p><p class="abstract"><strong>Results:</strong> Skewed starting value of 0.10 mg/100 g was chosen in the first design-level with a dose-window of &lt;0.0-0.20]. The three smolt obtained a reduction in Ct-value above 15%, and the dose-window adjusted with the lower boundary equals the previous dose. The five smolt at second design-level received 0.16 mg/100g with a dose-window [0.10-0.22]. Four smolt obtained above 15% and one of 0.5% reduction in cycle threshold (Ct)-value. Six smolt in the third design-level received 0.21 mg/100 g and one 0.16 mg/100 g. The mean Ct-value was reduced from 30.0 in the unstimulated situation to 25.0, 24.8 and 26.4 after BP-C2 stimulation of 0.10, 0.16 and 0.21 mg/100 g, respectively. The OED of BP-C2 related to IL-1β was estimated to 0.14 mg/100 g.</p><p class="abstract"><strong>Conclusions: </strong>Skewed starting value in the initial dose-window made the K-adjustment factor and dose-window stochastic. The RSP-procedure works in accordance to the expectation and estimated OED of BP-C2 sufficiently.</p><strong> </strong>

scholarly journals A Comparative Study between Pre-construction and Construction Phases of Champhai-Zokhawthar Road Construction, Mizoram: Air Quality and Noise Quality Assessments

2019 ◽  
Vol 7 (1) ◽  
pp. 47-53
Author(s):  
Lalven tluanga ◽  
◽  
H. Lalramnghinglova
Keyword(s):  
Economic Growth ◽  
Particulate Matter ◽  
Air Quality ◽  
Comparative Study ◽  
Noise Level ◽  
Road Construction ◽  
Suspended Particulate ◽  
The Mean ◽  
Negative Impacts

In recent years, Mizoram has made immense progress in various sectors and initiated developmental programmes for its economic growth. An important contributing factor to this development and growth is the transport connectivity projects. Although connectivity projects can boost economic growth, its negative effects cannot be neglected. In view of this, the present research studies the impacts of Champhai – Zokhawthar road construction on the air quality and noise quality of the region. This comparative study of the impact on the quality of air and noise pollution in the pre-construction phase and construction phase provide a clear-cut example of the negative impacts caused by road construction and provide a fresh outlook for formulation of improved management plans. Air quality assessment was carried out using High Volume Air Sampler and the following parameters were monitored – suspended particulate matter (SPM), respirable suspended particulate matter (RSPM), nitrogen dioxide (NO2) and sulphur dioxide (SO2). The results indicate that mean SPM concentration was increased by 22.82 µg/m3; RSPM concentration by 14.67 µg/m3; NO2 concentration by 4.08 µg/m3; and SO2 concentration was increased by 0.06 µg/m3 from the pre-construction phase to construction phase. Noise quality assessment was carried out at three sites – Zotlang, Melbuk and Zokhawthar by using Lutron SL-4001 Sound Level Meter and Leq, Lmax and Lmin were recorded and calculated. The mean noise level at Zotlang wasincreased by 8.72 dB (A) and at Melbuk the mean noise level was increased by 9.35 dB (A). However, at Zokhawthar, there was a decrease in mean noise level by 0.13 dB (A). From the present study, it is evident that road construction poses a threat to the air quality and noise quality of the study area and improved measuresneed to betaken to curb its negative impacts

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