Functional responses of haemocytes in the clam Tapes philippinarum from the Lagoon of Venice: fishing impact and seasonal variations

2003 ◽  
Vol 60 (8) ◽  
pp. 949-958 ◽  
Author(s):  
Valerio Matozzo ◽  
Luisa Da Ros ◽  
Loriano Ballarin ◽  
Francesca Meneghetti ◽  
Maria Gabriella Marin
Keyword(s):  
Seasonal Variations ◽  
Seasonal Pattern ◽  
Environmental Parameters ◽  
Neutral Red ◽  
Fishing Effort ◽  
Physiological Status ◽  
Lagoon Of Venice ◽  
Functional Responses ◽  
Tapes Philippinarum ◽  
Fishing Impact

In the last few years, the Manila clam (Tapes philippinarum) has been subjected to intense fishing effort in the Lagoon of Venice owing to their commercial importance. Because of the lack of data concerning fishing-induced immunomodulation in bivalves, the consequences of fishing impact on functional responses of clam haemocytes were investigated. Clams were seasonally collected from September 2000 to July 2001 from three sites: S. Angelo, a free-fishing area, and Chioggia, inside a licensed area for clam culture, in two zones characterised by fishing and non fishing, respectively. Haematocrit, phagocytosis, Neutral Red retention time, and lysozyme and superoxide dismutase activities were evaluated. No clear fishing effect was recorded, whereas a seasonal pattern of the cell para meters analysed was revealed. Alterations in functional responses of haemocytes seem to be more closely dependent on seasonal variations in both environmental parameters and physiological status of clams than on stress caused by fishing, and they may also be related to adaptation strategies of bivalves.

scholarly journals Diversity and Dynamics of Seaweed Associated Microbial Communities Inhabiting the Lagoon of Venice

2020 ◽  
Vol 8 (11) ◽  
pp. 1657
Author(s):  
Abdul-Salam Juhmani ◽  
Alessandro Vezzi ◽  
Mohammad Wahsha ◽  
Alessandro Buosi ◽  
Fabio De Pascale ◽  
...  
Keyword(s):  
Microbial Communities ◽  
Bacterial Communities ◽  
Host Response ◽  
Environmental Parameters ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Nutrient Concentrations ◽  
Lagoon Of Venice ◽  
Anthropogenic Stressors ◽  
Rich Diversity

Seaweeds are a group of essential photosynthetic organisms that harbor a rich diversity of associated microbial communities with substantial functions related to host health and defense. Environmental and anthropogenic stressors may disrupt the microbial communities and their metabolic activity, leading to host physiological alterations that negatively affect seaweeds’ performance and survival. Here, the bacterial communities associated with one of the most common seaweed, Ulva laetevirens Areshough, were sampled over a year at three sites of the lagoon of Venice affected by different environmental and anthropogenic stressors. Bacterial communities were characterized through Illumina sequencing of the V4 hypervariable region of 16S rRNA genes. The study demonstrated that the seaweed associated bacterial communities at sites impacted by environmental stressors were host-specific and differed significantly from the less affected site. Furthermore, these communities were significantly distinct from those of the surrounding seawater. The bacterial communities’ composition was significantly correlated with environmental parameters (nutrient concentrations, dissolved oxygen saturation, and pH) across sites. This study showed that several more abundant bacteria on U. laetevirens at stressed sites belonged to taxa related to the host response to the stressors. Overall, environmental parameters and anthropogenic stressors were shown to substantially affect seaweed associated bacterial communities, which reflect the host response to environmental variations.

scholarly journals A cross-sectional study of factors affecting seasonality in bipolar disorder

2014 ◽  
Vol 20 (2) ◽  
pp. 2 ◽  
Author(s):  
Pankaj Kumar Mittal ◽  
Shubham Mehta ◽  
Ram Kumar Solanki ◽  
Mukesh Kumar Swami ◽  
Parth Singh Meena
Keyword(s):  
Bipolar Disorder ◽  
Seasonal Variations ◽  
Affective Disorders ◽  
Seasonal Pattern ◽  
Cross Sectional Study ◽  
Sectional Study ◽  
Cross Sectional ◽  
Factors Affecting ◽  
Behavioural Patterns ◽  
Assessment Questionnaire

<p><strong>Background.</strong> Researchers have evinced interest in the effect of seasonal variations on mood and behavioural patterns in affective disorders. </p><p><strong>Objective. </strong>To study seasonality in bipolar disorder (BD) patients and also the factors affecting this seasonality. </p><p><strong>Method. </strong>Forty-nine patients with BD in euthymic phase were recruited and analysed using<strong> </strong>the<strong> </strong>Seasonal Pattern Assessment Questionnaire and Morningness-Eveningness Questionnaire. </p><p><strong>Results. </strong>Most of the patients were morning types but chronotype had no influence on seasonality. Age of patient and number of episodes were the most important factors affecting seasonality in BD. </p><p><strong>Conclusion. </strong>Seasonality and its influencing factors must be considered while managing bipolar disorder.</p>

scholarly journals Spatial and Seasonal Variations of Standardized Photosynthetic Parameters under Different Environmental Conditions for Young Planted Larix olgensis Henry Trees

Forests ◽  
2018 ◽  
Vol 9 (9) ◽  
pp. 522 ◽  
Author(s):  
Qiang Liu ◽  
Fengri Li
Keyword(s):  
Environmental Conditions ◽  
Seasonal Variations ◽  
Seasonal Pattern ◽  
Repeated Measurements ◽  
Seasonal Patterns ◽  
Photosynthetic Parameters ◽  
Relative Depth ◽  
Larix Olgensis ◽  
Vertical Variations ◽  
Larix Olgensis Henry

Understanding the spatial and seasonal variations in leaf physiology is critical for accurately modeling the carbon uptake, physiological processes and growth of entire canopies and stands. For a 17-year-old Larix olgensis Henry plantation, vertical whorl-by-whorl sampling and analyses of seasonally repeated measurements of major photosynthetic parameters were conducted, and the correlations between photosynthetic parameters and environmental conditions, leaf morphological traits and spatial position within the crown were analyzed. According to the correlations, the photosynthetic parameters were standardized based on the environmental conditions to avoid the influence of the changing environment on the patterns of spatial and seasonal variations of photosynthetic parameters. The results showed that the standardized light-saturated net photosynthetic rate (SPmax), standardized dark respiration (SRd) and standardized stomatal conductance under saturated light (Sgs-sat) were all negatively related to the relative depth into the crown (RDINC) throughout the growing season. However, their vertical patterns were different during the development of the phenological phase. In addition, different gradients of environmental conditions also influenced the values and the range of the vertical variation in photosynthesis. High temperature and low humidity usually resulted in smaller values and weaker vertical variations of SPmax and Sgs-sat, but larger values and more obvious vertical variations in SRd. SPmax and Sgs-sat usually exhibited a parabolic seasonal pattern in different vertical positions within the crown; however, SRd generally followed a concave pattern. These seasonal patterns were all weaker with increasing RDINC. Different environments also exhibited a significant influence on the seasonal patterns of photosynthesis. We suggested that standardization is necessary before analyzing spatial and seasonal variations. A single environmental condition could not represent the spatial and seasonal patterns under all gradients of the environment. Spatial and seasonal variations should be simultaneously analyzed because they are related to each other.

scholarly journals Current Understanding of the Driving Mechanisms for Spatiotemporal Variations of Atmospheric Speciated Mercury: A Critical Review

2016 ◽  
Author(s):  
Huiting Mao ◽  
Irene Cheng ◽  
Leiming Zhang
Keyword(s):  
Boundary Layer ◽  
Northern Hemisphere ◽  
Seasonal Variations ◽  
Seasonal Pattern ◽  
High Elevation ◽  
Future Research ◽  
Free Troposphere ◽  
Spatiotemporal Variations ◽  
Driving Mechanisms ◽  
Diurnal Patterns

Abstract. Understanding of spatial and temporal variations of atmospheric speciated mercury can advance our knowledge of mercury cycling in various environments. This review summarized spatiotemporal variations of total gaseous mercury or gaseous elemental mercury (TGM/GEM), gaseous oxidized mercury (GOM), and particulate-bound mercury (PBM) in various environments including oceans, continents, high elevation, the free troposphere, and low to high latitudes. In the marine boundary layer (MBL), the oxidation of GEM was generally thought to drive the diurnal and seasonal variations of TGM/GEM and GOM in most oceanic regions, leading to lower GEM and higher GOM from noon to afternoon and higher GEM during winter and higher GOM during spring-summer. At continental sites, the driving mechanisms of TGM/GEM diurnal patterns included surface and local emissions, boundary layer dynamics, GEM oxidation, and mountain-valley winds at high elevation sites. Oxidation of GEM and entrainment of GOM from the free troposphere influenced the diurnal patterns of GOM at continental sites. No pronounced diurnal variation was found for Tekran measured PBM at MBL and continental sites. Seasonal variations in TGM/GEM at continental sites were attributed to increased winter combustion, increased surface emissions during summer, and monsoons in Asia. GEM oxidation, free tropospheric transport, anthropogenic emissions, and wet deposition appeared to affect the seasonal pattern of GOM at continental sites. Since measurements were predominantly in the northern hemisphere (NH), increased PBM at continental sites during winter was primarily due to local/regional coal combustion and wood burning emissions. Long-term TGM measurements from the MBL and continental sites indicated an overall declining trend consistent with those of anthropogenic and natural emissions and potentially redox chemistry. The latitudinal gradient in TGM/GEM showed an increase from the southern to northern hemisphere due largely to the vast majority of Hg emissions in the NH. This gradient was insignificant during summer probably as a result of weaker meridional mixing. Aircraft measurements indicated no significant GEM gradient with altitude over the field campaign regions; however depletion of GEM was observed in air masses under stratospheric influence. Remaining questions and issues related to factors potentially contributing to the observed spatiotemporal variations were identified, and recommendations for future research needs were provided.

scholarly journals Spring peaks and autumn troughs identified in peripheral inflammatory markers during the peripartum period

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Hanna E. Henriksson ◽  
Richard A. White ◽  
Stavros I. Iliadis ◽  
Emma Fransson ◽  
Fotios C. Papadopoulos ◽  
...  
Keyword(s):  
Seasonal Variations ◽  
Inflammatory Markers ◽  
Inflammatory Marker ◽  
Seasonal Pattern ◽  
Cell Types ◽  
Seasonal Fluctuations ◽  
Clear Cut ◽  
Chemotactic Protein ◽  
Peripartum Period ◽  
Proximity Extension Assay

Abstract Seasonal variations have recently been described in biomarkers, cell types, and gene expression associated with the immune system, but so far no studies have been conducted among women in the peripartum period. It is of note that pregnancy complications and outcomes, as well as autoimmune diseases, have also been reported to exhibit seasonal fluctuations. We report here a clear-cut seasonal pattern of 23 inflammatory markers, analysed using proximity-extension assay technology, in pregnant women. The inflammatory markers generally peaked in the spring and had a trough in the autumn. During the postpartum period we found seasonality in one inflammatory marker, namely monocyte chemotactic protein 4 (MCP-4). Our findings suggest that seasonal variations in peripheral inflammatory markers are only observed during pregnancy. The results of this study could be valuable to professionals working within the field of immunology-related areas, and provide insight for the understanding of obstetric complications.

scholarly journals Quantifying relative fishing impact on fish populations based on spatio-temporal overlap of fishing effort and stock density

2013 ◽  
Vol 70 (3) ◽  
pp. 618-627 ◽  
Author(s):  
Morten Vinther ◽  
Margit Eero
Keyword(s):  
Fishing Effort ◽  
Fish Populations ◽  
Fishing Mortality ◽  
Fishing Impact ◽  
Management Measures ◽  
Stock Assessments ◽  
Spatio Temporal ◽  
Substantial Decline ◽  
The Impact ◽  
Temporal Overlap

Abstract Vinther, M., and Eero, M. 2013. Quantifying relative fishing impact on fish populations based on spatio-temporal overlap of fishing effort and stock density. – ICES Journal of Marine Science, 70: 618–627. Evaluations of the effects of management measures on fish populations are usually based on the analyses of population dynamics and estimates of fishing mortality from stock assessments. However, this approach may not be applicable in all cases, in particular for data-limited stocks, which may suffer from uncertain catch information and consequently lack reliable estimates of fishing mortality. In this study we develop an approach to obtain proxies for changes in fishing mortality based on effort information and predicted stock distribution. Cod in the Kattegat is used as an example. We use GAM analyses to predict local cod densities and combine this with spatio-temporal data of fishing effort based on VMS (Vessel Monitoring System). To quantify local fishing impact on the stock, retention probability of the gears is taken into account. The results indicate a substantial decline in the impact of the Danish demersal trawl fleet on cod in the Kattegat in recent years, due to a combination of closed areas, introduction of selective gears and changes in overall effort.

scholarly journals Atmospheric diurnal and semi-diurnal variations observed with GPS radio occultation soundings

2009 ◽  
Vol 9 (6) ◽  
pp. 25409-25441 ◽  
Author(s):  
F. Xie ◽  
D. L. Wu ◽  
C. O. Ao ◽  
A. J. Mannucci
Keyword(s):  
Seasonal Variations ◽  
Radio Occultation ◽  
Seasonal Pattern ◽  
Local Maximum ◽  
Diurnal Variations ◽  
Vertical Resolution ◽  
Solar Forcing ◽  
Diurnal Amplitude ◽  
High Vertical Resolution ◽  
The Tropics

Abstract. Diurnal and semi-diurnal variations, driven by solar forcing, are two fundamental modes in the Earth's weather and climate system. Radio occultation (RO) measurements from the six COSMIC satellites (Constellation Observing System for Meteorology Ionosphere and Climate) provide rather uniform global coverage with high vertical resolution, all-weather and diurnal sampling capability. This paper analyzes the diurnal and semi-diurnal variations of both temperature and refractivity from two-year (2007–2008) COSMIC RO measurements in the troposphere and stratosphere. The RO observations reveal both propagating and trapped vertical structures of diurnal and semi-diurnal variations, including transition regions near the tropopause where data with high vertical resolution are critical. In the tropics the diurnal amplitude in refractivity decreases with altitude from a local maximum in the planetary boundary layer and reaches the minimum around 14 km and then further increase amplitude in the stratosphere. The upward propagating component of the migrating diurnal tides in the tropics is clearly captured by the GPS RO measurements, which show a downward progression in phase from upper troposphere to the stratopause with a vertical wavelength of about 25 km. Below 500 hPa (~5.5 km), seasonal variations of the peak diurnal amplitude in the tropics follow the solor forcing change in latitude, while at 30 km the seasonal pattern reverses with the diurnal amplitude peaking at the opposite side of the equator relative to the solar forcing. Polar regions shows large diurnal variations in the stratosphere with strong seasonal variations and the cause(s) of these variations require further investigations.

Sign in / Sign up

Export Citation Format

Share Document