New data on Pinctada radiata (Leach, 1814) (Bivalvia: Pteriidae) in the Adriatic Sea

Slavica Petović; Vesna Mačić

doi:10.32582/aa.58.2.14

New data on Pinctada radiata (Leach, 1814) (Bivalvia: Pteriidae) in the Adriatic Sea

Acta Adriatica ◽

10.32582/aa.58.2.14 ◽

2017 ◽

Vol 58 (2) ◽

pp. 357-361

Author(s):

Slavica Petović ◽

Vesna Mačić

Keyword(s):

Standard Deviation ◽

Adriatic Sea ◽

Shell Height ◽

Pinctada Radiata

The first recorded population of Pinctada radiata in the Adriatic Sea was observed on the pier in Porto Montenegro marina (Tivat, Montenegro), in August 2016. Numerous individuals inhabited pier walls at a depth of 5 m. The shell height (SH) values for the 15 randomly collected individuals of P. radiata ranged between 32.2 mm and 52.1 mm with an average SH value of 38.3 mm (standard deviation ±6.1). Further surveys in Montenegro will provide information on the establishment of the observed population and what is its impact on local biodiversity.

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Comparative morphometric study of the invasive pearl oyster Pinctada radiata along the Tunisian coastline

Biologia ◽

10.2478/s11756-010-0023-9 ◽

2010 ◽

Vol 65 (2) ◽

Cited By ~ 5

Author(s):

Sabiha Tlig-Zouari ◽

Lotfi Rabaoui ◽

Ikram Irathni ◽

Moctar Diawara ◽

Oum Hassine

Keyword(s):

Size Structure ◽

Shell Height ◽

Maximum Size ◽

Pearl Oyster ◽

Morphometric Study ◽

Distribution Analysis ◽

Relative Growth ◽

Size Groups ◽

Bizerta Lagoon ◽

Pinctada Radiata

AbstractIn order to study the relative growth of the pearl oyster Pinctada radiata in Tunisia, a total of 330 individuals of this species were collected from six sites along the Tunisian coastline. Quantitative measurements of collected oysters were conducted for shell height, shell length, shell width, hinge length, height and width of the nacreous part and wet weight. The size structure of the sampled populations was described and the relative growth between different morphometric characteristics was estimated as allometric growth lines for the six P. radiata samples. It appeared that the majority of examined samples were dominated by large individuals that exceed a shell height of 42 mm. The maximum size (100.5 mm), recorded in Bizerta lagoon, is bigger than that recorded elsewhere in particular in the Red Sea. Size distribution analysis also showed that the majority of P. radiata samples were dominated by two or more size groups. Differences of allometric regression were found between the examined samples for the tested relationships. Moreover, the Factorial Discriminant Analysis, coupled with Ascending Hierarchic Classification, classified the sub-populations according to geographic locations.

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Stratigraphic changes in shell size of a turritellid gastropod in the Holocene fossil record of the Po prodelta (Northern Adriatic Sea)

10.5194/egusphere-egu21-9604 ◽

2021 ◽

Author(s):

Angela Scheidl ◽

Michaela Berensmeier ◽

Rafal Nawrot ◽

Paolo G. Albano ◽

Adam Tomašových ◽

...

Keyword(s):

Water Depth ◽

Similar Pattern ◽

Adriatic Sea ◽

Size Structure ◽

Shell Height ◽

Sediment Cores ◽

Northern Adriatic Sea ◽

Shell Size ◽

Northern Adriatic ◽

Lower Abundance

<div> Over the last century, the northern Adriatic Sea has faced multiple ecological threats such as hypoxic events, eutrophication, pollution by heavy metals and plastics, and bottom trawling. These impacts were associated with major changes in the composition of benthic communities, particularly a decline in the abundance of Turritellinella tricarinata (= Turritella communis), the dominant gastropod species in the previously widespread Turritella-biocenosis of the northern Adriatic muddy bottoms. In this study, we reconstruct changes in abundance and size structure of T. tricarinata populations over the last 6000 years to better understand the drivers responsible for its recent decline and to provide a historical baseline for assessing potential recovery. We studied sediment cores from two locations in the western Northern Adriatic Sea: (1) distal zones of Po prodelta based on a 3-meter-long gravity core collected at 31 m water depth comprising a condensed record of the last ~9,100 years, (2) proximal zones of Po prodelta based on five 1.5-meter-long piston cores taken at 21 m water depth in the Po prodelta, which capture the last 100-150 years. Core chronologies are based on radiocarbon-calibrated amino-acid racemization analyses of bivalve shells. We analysed changes in the abundance and shell height of T. tricarinata in each increment of the cores. In total, 600 specimens have been measured. All stations show a similar pattern in shell abundance: a climax in the early 20th century and a strong decrease in the late 20th century. The proximal records of Po prodelta show a negative correlation between abundance and median shell size, with larger size and lower abundance in the late the 20th century, a period characterized by recurrent severe hypoxic events. The 3-meter-long offshore core contains on average smaller specimens, but reflects a similar pattern: the number of larger specimens (>10 mm) and median shell sizes increase slightly towards the core top while total abundance declines. This trend towards larger shell size and lower abundance may reflect the complex effect of nutrient enrichment in a highly disturbed environment. During the last century Turritella communis might experience higher growth rates and lower predation but simultaneously reduced recruitment due to hypoxia and pollution. </div>

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Nucleic Acid Molecules Prepared by Monolayer Techniques

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100094140 ◽

1972 ◽

Vol 30 ◽

pp. 178-179

Author(s):

Dimitrij Lang

Keyword(s):

Electron Microscopy ◽

Standard Deviation ◽

Nucleic Acid ◽

Cytochrome C ◽

Nucleic Acids ◽

Contour Length ◽

Sample Standard Deviation ◽

Molecular Weights ◽

Length Measurements ◽

Protein Monolayer

The success of the protein monolayer technique for electron microscopy of individual DNA molecules is based on the prevention of aggregation and orientation of the molecules during drying on specimen grids. DNA adsorbs first to a surface-denatured, insoluble cytochrome c monolayer which is then transferred to grids, without major distortion, by touching. Fig. 1 shows three basic procedures which, modified or not, permit the study of various important properties of nucleic acids, either in concert with other methods or exclusively:1) Molecular weights relative to DNA standards as well as number distributions of molecular weights can be obtained from contour length measurements with a sample standard deviation between 1 and 4%.

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Reliability of the Minimum Masking Level as Outcome Variable in Tinnitus Clinical Research

American Journal of Audiology ◽

10.1044/2020_aja-20-00047 ◽

2020 ◽

Vol 29 (3) ◽

pp. 429-435

Author(s):

Patricia C. Mancini ◽

Richard S. Tyler ◽

Hyung Jin Jun ◽

Tang-Chuan Wang ◽

Helena Ji ◽

...

Keyword(s):

Standard Deviation ◽

High Frequency ◽

Pearson Correlation ◽

Correlation Coefficients ◽

Outcome Variable ◽

Reliable Estimate ◽

Moderate Correlation ◽

Trained Subjects ◽

The Relationship ◽

Minimum Intensity

Purpose The minimum masking level (MML) is the minimum intensity of a stimulus required to just totally mask the tinnitus. Treatments aimed at reducing the tinnitus itself should attempt to measure the magnitude of the tinnitus. The objective of this study was to evaluate the reliability of the MML. Method Sample consisted of 59 tinnitus patients who reported stable tinnitus. We obtained MML measures on two visits, separated by about 2–3 weeks. We used two noise types: speech-shaped noise and high-frequency emphasis noise. We also investigated the relationship between the MML and tinnitus loudness estimates and the Tinnitus Handicap Questionnaire (THQ). Results There were differences across the different noise types. The within-session standard deviation averaged across subjects varied between 1.3 and 1.8 dB. Across the two sessions, the Pearson correlation coefficients, range was r = .84. There was a weak relationship between the dB SL MML and loudness, and between the MML and the THQ. A moderate correlation ( r = .44) was found between the THQ and loudness estimates. Conclusions We conclude that the dB SL MML can be a reliable estimate of tinnitus magnitude, with expected standard deviations in trained subjects of about 1.5 dB. It appears that the dB SL MML and loudness estimates are not closely related.

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Bedingungen für den Erfolg übergewichtiger und adipöser Kinder in einem ambulanten Programm zur Gewichtsreduktion durch Veränderungen des Lebensstils

Zeitschrift für Kinder- und Jugendpsychiatrie und Psychotherapie ◽

10.1024/1422-4917/a000059 ◽

2010 ◽

Vol 38 (5) ◽

pp. 351-360 ◽

Cited By ~ 1

Author(s):

Wilfried Pott ◽

Georg Fröhlich ◽

Özgür Albayrak ◽

Johannes Hebebrand ◽

Ursula Pauli-Pott

Keyword(s):

Body Mass Index ◽

Standard Deviation ◽

Body Mass ◽

Standard Deviation Score ◽

Psychische Belastung ◽

Deviation Score ◽

Höheres Alter

Fragestellung: Es wurde der Frage nachgegangen, ob sich erfolgreiche Teilnehmer eines ambulanten familienzentrierten Gewichtskontrollprogramms durch spezifische familiäre und psychologische Charakteristiken auszeichnen. Einbezogen wurden die psychosoziale Risikobelastung der Familie, Depressivität und Bindungsstil der Hauptbezugsperson, der Body mass index (BMI) und der BMI-Standardabweichungswert («Standard deviation score», SDS) des teilnehmenden Kindes und der Familienmitglieder sowie die individuelle psychische Belastung des teilnehmenden Kindes. Methodik: Die Daten wurden per Interview und Fragebogen vor dem Behandlungsbeginn erhoben. Von 136 in das Programm aufgenommenen übergewichtigen und adipösen Kindern zwischen 7 und 15 Jahren beendeten 116 das 12-monatige Interventionsprogramm. Von diesen zeigten 100 (85,3 %) eine Reduktion des BMI-SDS und 79 (68.1 %) eine mehr als 5 %ige Reduktion des BMI-SDS. Diese «erfolgreichen» Kinder wurden mit 56 «nicht erfolgreichen» (Abbrecher und Kinder mit einer 5 %igen oder geringeren Reduktion des BMI-SDS) verglichen. Ergebnisse: Nicht erfolgreiche Kinder unterschieden sich von den erfolgreichen durch ein höheres Alter, eine höhere psychosoziale Risikobelastung, Depressivität und einen vermeidenden Bindungsstil der Mutter sowie durch das Vorhandensein adipöser Geschwister. In einer logistischen Regressionsanalyse zeigten sich mütterliche Depressivität und das Vorhandensein adipöser Geschwister als beste und voneinander unabhängige Prädiktoren. Schlussfolgerungen: Um die spezifischen Bedürfnisse der Familien zu erfüllen und einen Misserfolg zu verhindern, sollten zusätzliche Programmbausteine zur spezifischen Unterstützung von Jugendlichen mit adipösen Geschwistern und Müttern mit Depressionen und vermeidenden Bindungsstil entwickelt werden. Die Wirksamkeit dieser Module muss dann in weiteren Studien überprüft werden.

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