scholarly journals Species composition of ichthyoplankton assemblages: a response to seasonal temperature changes

2019 ◽  
Author(s):  
ÇETIN KESKIN ◽  
DANIEL PAULY
Keyword(s):  
Eastern Mediterranean ◽  
Geometric Mean ◽  
Taxonomic Composition ◽  
Sea Surface ◽  
Seasonal Temperature ◽  
Type Ii ◽  
Temperature Changes ◽  
Preferred Temperatures ◽  
The Mean ◽  
Of Greece

The ‘mean temperature of the catch’ (MTC; Cheung et al. 2013, Nature 497: 365-368.) was computed for 59 ichthyoplankton surveys conducted in several regions of the Eastern Mediterranean (off the coasts of Greece and Turkey) and in the Black and Marmara Seas. This covered 162 fish species whose preferred temperatures (PTs) were derived mainly from the data used to derive Aquamaps (see www.aquamaps.org).  The (geometric mean) MTCs estimates from these 59 surveys correlated strongly with observed sea surface temperatures (SSTs), once account of the sampling regions was taken. Here, this relationship is quantified using a Type II or ‘functional’ (multiple) regression. Overall, the results suggested that the MTC could be an important descriptor of the taxonomic composition and temperature affinities of ichthyoplankton assemblages.

scholarly journals Spatial Variability and Trends of Marine Heat Waves in the Eastern Mediterranean Sea over 39 Years

2021 ◽  
Vol 9 (6) ◽  
pp. 643
Author(s):  
Omneya Ibrahim ◽  
Bayoumy Mohamed ◽  
Hazem Nagy
Keyword(s):  
Spatial Variability ◽  
Mediterranean Sea ◽  
Heat Waves ◽  
Eastern Mediterranean ◽  
Aegean Sea ◽  
Sea Surface ◽  
Sea Level Pressure ◽  
Eastern Mediterranean Sea ◽  
Marine Life ◽  
The Mean

Marine heatwaves (MHWs) can cause devastating impacts on marine life. The frequency of MHWs, gauged with respect to historical temperatures, is expected to rise significantly as the climate continues to warm. The MHWs intensity and count are pronounced with many parts of the oceans and semi enclosed seas, such as Eastern Mediterranean Sea (EMED). This paper investigates the descriptive spatial variability and trends of MHW events and their main characteristics of the EMED from 1982 to 2020 using Sea Surface Temperature (SST) data obtained from the National Oceanic and Atmospheric Administration Optimum Interpolation ([NOAA] OI SST V2.1). Over the last two decades, we find that the mean MHW frequency and duration increased by 40% and 15%, respectively. In the last decade, the shortest significant MHW mean duration is 10 days, found in the southern Aegean Sea, while it exceeds 27 days off the Israeli coast. The results demonstrate that the MHW frequency trend increased by 1.2 events per decade between 1982 and 2020, while the MHW cumulative intensity (icum) trend increased by 5.4 °C days per decade. During the study period, we discovered that the maximum significant MHW SST event was 6.35 °C above the 90th SST climatology threshold, lasted 7 days, and occurred in the year 2020. It was linked to a decrease in wind stress, an increase in air temperature, and an increase in mean sea level pressure.

scholarly journals   Reactions of grape varieties to climate changes in North East Slovenia

2012 ◽  
Vol 58 (No. 1) ◽  
pp. 34-41 ◽  
Author(s):  
S. Vršič ◽  
T. Vodovnik
Keyword(s):  
Growth Period ◽  
Soluble Solids ◽  
Seasonal Temperature ◽  
Total Acidity ◽  
Temperature Changes ◽  
Grape Berries ◽  
Growing Period ◽  
North East ◽  
The Mean ◽  
Grape Varieties

This work examined the trend of changes in temperature from 1950 to 2009 recorded by the Maribor meteorological station, and from 1980 to 2009 the dynamics of grape ripening of early-, medium late-, and late-ripening vine varieties in the Slovenian Styria wine-growing region in North East Slovenia. Based on the data associated with the content of soluble solids, total acidity, and the recommended date of harvest in a particular year, the trends towards shortening of the grapevine growing period were calculated. In general, temperature changes were more significant since 1980 than between 1950 and 1979. The mean annual and seasonal temperature significantly increased, i.e. 0.06°C per year. The growing season was shortened in all studied varieties from 15 to 27 days. Trends showed significantly decreasing content of total acidity, which can be considered explicitly as a consequence of higher temperatures during the growth period and ripening of grape berries. Grapes now ripen at temperatures which are approximately by 2°C higher than 30 years ago. Regarding the total acidity content of the late-ripening varieties, the influence of higher temperatures is positive. Minor changes were found in precipitations rates.  

scholarly journals Millennial-scale sea surface temperature changes in the eastern Mediterranean (Nile River Delta region) over the last 27,000 years

2010 ◽  
Vol 25 (1) ◽  
Author(s):  
Isla S. Castañeda ◽  
Enno Schefuß ◽  
Jürgen Pätzold ◽  
Jaap S. Sinninghe Damsté ◽  
Syee Weldeab ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Eastern Mediterranean ◽  
River Delta ◽  
Sea Surface ◽  
Nile River ◽  
Delta Region ◽  
Temperature Changes ◽  
Millennial Scale

scholarly journals 200 Year interruption of Holocene sapropel formation in the Adriatic Sea

1997 ◽  
Vol 16 (2) ◽  
pp. 97-108 ◽  
Author(s):  
E. J. Rohling ◽  
F. J. Jorissen ◽  
H. C. De Stigter
Keyword(s):  
Deep Water ◽  
Adriatic Sea ◽  
Eastern Mediterranean ◽  
Mediterranean Area ◽  
Sea Surface ◽  
Stable Mode ◽  
Temperature Changes ◽  
Geochemical Study ◽  
Eastern Mediterranean Area ◽  
Reservoir Age

Abstract. An interruption of Holocene sapropel S1 is found in cores from various subbasins of the eastern Mediterranean. In core IN68-9 from the Adriatic Sea, sapropel S1 is dated between 8300 and 6340 BP, interrupted between 7100 and 6900 BP (14C years uncorrected for reservoir age). Lithology and variations in the foraminiferal faunas suggest that the interruption is genuine, and not the result of resedimentation. The results indicate that S1 was deposited within a period of enhanced levels of productivity (resulting from increased seasonal contrasts) which started around 9300 BP and ended around 5200 BP. The onset, interruption, and final ending of S1 deposition in the Adriatic Sea, however, appear to have been triggered by changes in ventilation of the basin related to changes in sea surface temperature (SST). Although the rough estimates of SST change are relatively small (< 2°C), they still are significant when compared with the relative SST changes considered necessary to upset convection in the Adriatic. Moreover, recent studies show that the influence of the inferred temperature changes should be viewed in combination with that of reduced salinities due to (1) the deglaciation, and (2) increased humidity in the eastern Mediterranean area during the deposition of S1. The lithological and benthic foraminiferal evidence that sapropel formation in the Adriatic Sea ended around 6340 BP contrasts with the conclusion from a recent geochemical study that sapropel formation in the open eastern Mediterranean would have ended as late as 5000 BP. More significantly, the results of the present study combined with other reports on sapropel interruptions suggest that the process of sapropel formation is not a very stable mode in the basin, but that it may be relatively easily interrupted in response to subtle rearrangements in the balance between productivity and, especially, deep water ventilation.

DMSA-scintigraphy in paediatrics: Is the evaluation of the geometric mean necessary for the calculation of the differential renal function?

2001 ◽  
Vol 40 (04) ◽  
pp. 107-110 ◽  
Author(s):  
B. Roßmüller ◽  
S. Alalp ◽  
S. Fischer ◽  
S. Dresel ◽  
K. Hahn ◽  
...  
Keyword(s):  
Renal Function ◽  
Geometric Mean ◽  
Region Of Interest ◽  
Posterior View ◽  
Renal Abnormality ◽  
Anterior View ◽  
Differential Renal Function ◽  
The Mean ◽  
The Right ◽  
To Receive

SummaryFor assessment of differential renal function (PF) by means of static renal scintigraphy with Tc-99m-dimer-captosuccinic acid (DMSA) the calculation of the geometric mean of counts from the anterior and posterior view is recommended. Aim of this retrospective study was to find out, if the anterior view is necessary to receive an accurate differential renal function by calculating the geometric mean compared to calculating PF using the counts of the posterior view only. Methods: 164 DMSA-scans of 151 children (86 f, 65 m) aged 16 d to 16 a (4.7 ± 3.9 a) were reviewed. The scans were performed using a dual head gamma camera (Picker Prism 2000 XP, low energy ultra high resolution collimator, matrix 256 x 256,300 kcts/view, Zoom: 1.6-2.0). Background corrected values from both kidneys anterior and posterior were obtained. Using region of interest technique PF was calculated using the counts of the dorsal view and compared with the calculated geometric mean [SQR(Ctsdors x Ctsventr]. Results: The differential function of the right kidney was significantly less when compared to the calculation of the geometric mean (p<0.01). The mean difference between the PFgeom and the PFdors was 1.5 ± 1.4%. A difference > 5% (5.0-9.5%) was obtained in only 6/164 scans (3.7%). Three of 6 patients presented with an underestimated PFdors due to dystopic kidneys on the left side in 2 patients and on the right side in one patient. The other 3 patients with a difference >5% did not show any renal abnormality. Conclusion: The calculation of the PF from the posterior view only will give an underestimated value of the right kidney compared to the calculation of the geometric mean. This effect is not relevant for the calculation of the differntial renal function in orthotopic kidneys, so that in these cases the anterior view is not necesssary. However, geometric mean calculation to obtain reliable values for differential renal function should be applied in cases with an obvious anatomical abnormality.

The global dynamics of stochastic Holling type II predator-prey models with non constant mortality rate

Filomat ◽  
2017 ◽  
Vol 31 (18) ◽  
pp. 5811-5825
Author(s):  
Xinhong Zhang
Keyword(s):  
Mortality Rate ◽  
Stochastic Model ◽  
Sufficient Conditions ◽  
Positive Periodic Solution ◽  
Global Dynamics ◽  
Type Ii ◽  
Predator Prey ◽  
Persistence In The Mean ◽  
The Mean ◽  
Predator Prey Models

In this paper we study the global dynamics of stochastic predator-prey models with non constant mortality rate and Holling type II response. Concretely, we establish sufficient conditions for the extinction and persistence in the mean of autonomous stochastic model and obtain a critical value between them. Then by constructing appropriate Lyapunov functions, we prove that there is a nontrivial positive periodic solution to the non-autonomous stochastic model. Finally, numerical examples are introduced to illustrate the results developed.

Flow cytometric identification and isolation of hypertrophic type II pneumocytes after partial pneumonectomy

1989 ◽  
Vol 257 (3) ◽  
pp. C528-C536 ◽  
Author(s):  
B. D. Uhal ◽  
S. R. Rannels ◽  
D. E. Rannels
Keyword(s):  
Gradient Centrifugation ◽  
Type Ii Cells ◽  
Type Ii ◽  
Acridine Orange Staining ◽  
Flow Cytometric ◽  
Percoll Density Gradient Centrifugation ◽  
Type Ii Pneumocytes ◽  
The Mean ◽  
Cellular Dna ◽  
The Right

Type II pneumocytes were isolated by either Percoll density gradient centrifugation or by immunoglobulin G (IgG) panning from the lungs of normal rats and the right lung of rats subjected to left pneumonectomy. Cells were studied at 7- (pnx-7) and 15- (pnx-15) days postoperative, times during and after, respectively, rapid compensatory growth of the right lung. Acridine orange staining permitted resolution of type II cells from contaminants on the basis of high red fluorescence (greater than 590 nm). Simultaneous measurement of forward-angle light scatter (FALS) suggested a shift of pnx-7 cells toward greater size, which was reversed in pnx-15 cells. By Percoll gradient isolation, approximately 15% of pnx-7 cells analyzed were above the mean FALS of control cells. In contrast, approximately 30% of the pnx-7 cells isolated by IgG panning were above the mean FALS of corresponding control cells. Biochemical analyses of pnx-7 cells separated by cell sorting into "high FALS" and "low FALS" subgroups revealed that high FALS type II cells contained 50% more protein (P less than 0.05) and 140% more RNA (P less than 0.01) than low FALS cells, with no significant change in cellular DNA content. These data are consistent with previous studies of type II cells isolated from the lungs of pneumonectomized animals and confirm the presence of hypertrophic cells in these preparations. They provide a foundation from which to design further flow cytometric studies of the role of hypertrophic type II pneumocytes in compensatory lung growth.

scholarly journals Absolute seasonal temperature estimates from clumped isotopes in bivalve shells suggest warm and variable greenhouse climate

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Niels J. de Winter ◽  
Inigo A. Müller ◽  
Ilja J. Kocken ◽  
Nicolas Thibault ◽  
Clemens V. Ullmann ◽  
...  
Keyword(s):  
Seasonal Variability ◽  
Sea Water ◽  
Isotope Composition ◽  
Sea Surface ◽  
Mean Annual Temperature ◽  
Seasonal Temperature ◽  
Sea Surface Temperatures ◽  
Surface Temperatures ◽  
Temperature Reconstructions ◽  
Bivalve Shells

AbstractSeasonal variability in sea surface temperatures plays a fundamental role in climate dynamics and species distribution. Seasonal bias can also severely compromise the accuracy of mean annual temperature reconstructions. It is therefore essential to better understand seasonal variability in climates of the past. Many reconstructions of climate in deep time neglect this issue and rely on controversial assumptions, such as estimates of sea water oxygen isotope composition. Here we present absolute seasonal temperature reconstructions based on clumped isotope measurements in bivalve shells which, critically, do not rely on these assumptions. We reconstruct highly precise monthly sea surface temperatures at around 50 °N latitude from individual oyster and rudist shells of the Campanian greenhouse period about 78 million years ago, when the seasonal range at 50 °N comprised 15 to 27 °C. In agreement with fully coupled climate model simulations, we find that greenhouse climates outside the tropics were warmer and more seasonal than previously thought. We conclude that seasonal bias and assumptions about seawater composition can distort temperature reconstructions and our understanding of past greenhouse climates.

scholarly journals Minimal Invasive Surgery for Gastroesophageal Reflux Disease and Hiatus Hernia—Our Experience: A Case Series with Review of Literature

2021 ◽  
Author(s):  
Rafique Umer Harvitkar ◽  
Abhijit Joshi
Keyword(s):  
Retrospective Study ◽  
Gastroesophageal Reflux Disease ◽  
Gastroesophageal Reflux ◽  
Operating Time ◽  
Type I ◽  
Type Ii ◽  
The Mean ◽  
Gerd Symptoms

Abstract Introduction Laparoscopic fundoplication (LF) has almost completely replaced the open procedure performed for gastroesophageal reflux disease (GERD) and hiatus hernia (HH). Several studies have suggested that long-term results with surgery for GERD are better than a medical line of management. In this retrospective study, we outline our experience with LF over 10 years. Also, we analyze the factors that would help us in better patient selection, thereby positively affecting the outcomes of surgery. Patients and Methods In this retrospective study, we identified 27 patients (14 females and 13 males) operated upon by a single surgeon from 2010 to 2020 at our institution. Out of these, 25 patients (12 females and 13 males) had GERD with type I HH and 2 (both females) had type II HH without GERD. The age range was 24 to 75 years. All patients had undergone oesophago-gastro-duodenoscopy (OGD scopy). A total of 25 patients had various degrees of esophagitis. Two patients had no esophagitis. These patients were analyzed for age, sex, symptoms, preoperative evaluation, exact procedure performed (Nissen’s vs. Toupet’s vs. cruroplasty + gastropexy), morbidity/mortality, and functional outcomes. They were also reviewed to examine the length of stay, length of procedure, complications, and recurrent symptoms on follow-up. Symptoms were assessed objectively with a score for six classical GERD symptoms preoperatively and on follow-up at 1-, 4- and 6-weeks postsurgery. Further evaluation was performed after 6 months and then annually for 2 years. Results 14 females (53%) and 13 males (48%) with a diagnosis of GERD (with type I HH) and type II HH were operated upon. The mean age was 46 years (24–75 years) and the mean body mass index (BMI) was 27 (18–32). The range of duration of the preoperative symptoms was 6 months to 2 years. The average operating time dropped from 130 minutes for the first 12 cases to 90 minutes for the last 15 cases. The mean hospital stay was 3 days (range: 2–4 days). In the immediate postoperative period, 72% (n = 18) of the patients reported improvement in the GERD symptoms, while 2 (8%) patients described heartburn (grade I, mild, daily) and 1 (4%) patient described bloating (grade I, daily). A total of 5 patients (20%) reported mild dysphagia to solids in the first 2 postoperative weeks. These symptoms settled down after 2 to 5 weeks of postoperative proton-pump inhibitor (PPI) therapy and by adjusting consistency of oral feeds. There was no conversion to open, and we observed no perioperative mortality. There were no patients who underwent redo surgeries in the series. Conclusion LF is a safe and highly effective procedure for a patient with symptoms of GERD, and it gives long-term relief from the symptoms. Stringent selection criteria are necessary to optimize the results of surgery. Experience is associated with a significant reduction of operating time.

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