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.

The Seasonality of Marriages and Baptisms in some Devon Seafaring Parishes

2021 ◽  
pp. 5-26
Author(s):  
Marion R Hardy
Keyword(s):  
Seasonal Variations ◽  
Seasonal Pattern ◽  
Seasonal Patterns ◽  
Over Time

This article shows that, for a sample of Devon parishes during the period c.1700–1850, there were seasonalities in the events of marriages and baptisms in general, but that in parishes linked to seafaring, especially in the Newfoundland trade, the seasonal patterns were much greater and occurred in different months. Seasonal variations also declined and changed over time, which in part was due to the changing economies of the maritime parishes, especially after 1800 when the Newfoundland trade changed and declined. It cannot be claimed that this trade was exclusively responsible for the seasonal pattern, but the results confirm that seafaring was linked to the variation in the number of marriages and baptisms from month to month.

scholarly journals Dynamic Simulation of the Crown Net Photosynthetic Rate for Young Larix olgensis Henry Trees

Forests ◽  
2019 ◽  
Vol 10 (4) ◽  
pp. 321
Author(s):  
Qiang Liu ◽  
Longfei Xie ◽  
Fengri Li
Keyword(s):  
Net Photosynthetic Rate ◽  
Dynamic Simulation ◽  
Photosynthetic Rate ◽  
Elevation Angle ◽  
Distribution Model ◽  
Co2 Uptake ◽  
Relative Depth ◽  
Larix Olgensis ◽  
Larix Olgensis Henry

Numerical integration of the instantaneous net photosynthetic rate (An) is a common method for calculating the long-term CO2 uptake of trees, and accurate dynamic simulation of the crown An has been receiving substantial attention. Tree characteristics are challenging to assess given their aerodynamically coarse crown properties, spatiotemporal variation in leaf functional traits and microenvironments. Therefore, the variables associated with the dynamic variations in the crown An must be identified. The relationships of leaf temperature (Tleaf), the vapor pressure deficit (VPD), leaf mass per area (LMA) and the relative depth into the crown (RDINC) with the parameters of the photosynthetic light-response (PLR) model of Larix olgensis Henry were analyzed. The LMA, RDINC and VPD were highly correlated with the maximum net photosynthetic rate (Amax). The VPD was the key variable that mainly determined the variation in the apparent quantum yield (AQY). Tleaf exhibited a significant exponential correlation with the dark respiration rate (Rd). According to the above correlations, the crown PLR model of L. olgensis trees was constructed by linking VPD, LMA and RDINC to the original PLR equation. The model performed well, with a high coefficient of determination (R2) value (0.883) and low root mean square error (RMSE) value (1.440 μmol m−2 s−1). The extinction coefficient (k) of different pseudowhorls within a crown was calculated by the Beer–Lambert equation based on the observed photosynthetically active radiation (PAR) distribution. The results showed that k was not a constant value but varied with the RDINC, solar elevation angle (ψ) and cumulative leaf area of the whole crown (CLA). Thus, we constructed a k model by reparameterizing the power function of RDINC with the ψ and CLA, and the PAR distribution within a crown was therefore well estimated (R2 = 0.698 and RMSE = 174.4 μmol m−2 s−1). Dynamic simulation of the crown An for L. olgensis trees was achieved by combining the crown PLR model and dynamic PAR distribution model. Although the models showed some weakened physiological biochemical processes during photosynthesis, they enabled the estimation of long-term CO2 uptake for an L. olgensis plantation, and the results could be easily fitted to gas-exchange measurements.

scholarly journals Seasonality in schizophrenia—An analysis of a nationwide registry with 110,735 hospital admissions

2020 ◽  
Vol 63 (1) ◽  
Author(s):  
B. Hinterbuchinger ◽  
D. König ◽  
A. Gmeiner ◽  
S. Listabarth ◽  
M. Fellinger ◽  
...  
Keyword(s):  
Seasonal Variations ◽  
Multiple Testing ◽  
Hospital Admissions ◽  
Seasonal Pattern ◽  
Influencing Factor ◽  
Total Sample ◽  
Seasonal Patterns ◽  
Significant Difference ◽  
Level Of Significance ◽  
The Impact

Abstract Background. Seasonal patterns in hospitalizations have been observed in various psychiatric disorders, however, it is unclear whether they also exist in schizophrenia. Previous studies found mixed results and those reporting the presence of seasonality differ regarding the characteristics of these patterns. Further, they are inconclusive whether sex is an influencing factor. The aim of this study was therefore to examine if seasonal patterns in hospitalizations can be found in schizophrenia, with special regard to a possible influence of sex, by using a large national dataset. Methods. Data on all hospital admissions within Austria due to schizophrenia (F20.0–F20.6) for the time period of 2003–2016 were included. Age standardized monthly variation of hospitalization for women and men was analyzed and the level of significance adjusted for multiple testing. Results. The database comprised of 110,735 admissions (59.6% men). Significant seasonal variations were found in the total sample with hospitalization peaks in January and June and a trough in December (p < 0.0001). No significant difference in these patterns was found between women and men with schizophrenia (p < 0.0001). Conclusion. Our study shows that schizophrenia-related hospitalizations follow a seasonal pattern in both men and women. The distribution of peaks might be influenced by photoperiod changes which trigger worsening of symptoms and lead to exacerbations in schizophrenia. Further research is necessary to identify underlying factors influencing seasonal patterns and to assess whether a subgroup of patients with schizophrenia is especially vulnerable to the impact of seasonal variations.

Seasonal Variation of Suicide in the City of São Paulo, Brazil, 1996–2010

Crisis ◽  
2014 ◽  
Vol 35 (1) ◽  
pp. 5-9 ◽  
Author(s):  
Daniel Hideki Bando ◽  
Fernando Madalena Volpe
Keyword(s):  
Seasonal Pattern ◽  
Total Sample ◽  
Sao Paulo ◽  
Seasonal Patterns ◽  
São Paulo ◽  
Health Statistics ◽  
Males And Females ◽  
June July ◽  
The City ◽  
Over Time

Background: In light of the few reports from intertropical latitudes and their conflicting results, we aimed to replicate and update the investigation of seasonal patterns of suicide occurrences in the city of São Paulo, Brazil. Methods: Data relating to male and female suicides were extracted from the Mortality Information Enhancement Program (PRO-AIM), the official health statistics of the municipality of São Paulo. Seasonality was assessed by studying distribution of suicides over time using cosinor analyses. Results: There were 6,916 registered suicides (76.7% men), with an average of 39.0 ± 7.0 observed suicides per month. For the total sample and for both sexes, cosinor analysis estimated a significant seasonal pattern. For the total sample and for males suicide peaked in November (late spring) with a trough in May–June (late autumn). For females, the estimated peak occurred in January, and the trough in June–July. Conclusions: A seasonal pattern of suicides was found for both males and females, peaking in spring/summer and dipping in fall/winter. The scarcity of reports from intertropical latitudes warrants promoting more studies in this area.

scholarly journals Cardiac Parasympathetic Withdrawal and Sympathetic Activity: Effect of Heat Exposure on Heart Rate Variability

2021 ◽  
Vol 18 (11) ◽  
pp. 5934
Author(s):  
Oriol Abellán-Aynés ◽  
Pedro Manonelles ◽  
Fernando Alacid
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Environmental Conditions ◽  
Sympathetic Activity ◽  
Heat Exposure ◽  
Repeated Measurements ◽  
Control Group ◽  
Poincaré Plot ◽  
Activity Effect ◽  
And Control

(1) Background: Research on heart rate variability has increased in recent years and the temperature has not been controlled in some studies assessing repeated measurements. This study aimed to analyze how heart rate variability may change based on environmental temperature during measurement depending on parasympathetic and sympathetic activity variations. (2) Methods: A total of 22 volunteers participated in this study divided into an experimental (n = 12) and control group (n = 10). Each participant was assessed randomly under two different environmental conditions for the experimental group (19 °C and 35 °C) and two identical environmental conditions for the control group (19 °C). During the procedure, heart rate variability measurements were carried out for 10 min. (3) Results: Significantly changes were observed for time and frequency domains as well as Poincaré plot variables after heat exposure (p < 0.05). These findings were not observed in the control group, whose conditions between measurements did not change. (4) Conclusions: The reduction of heart rate variability due to exposure to hot conditions appears to be produced mostly by a parasympathetic withdrawal rather than a sympathetic activation. Therefore, if consecutive measurements have to be carried out, these should always be done under the same temperature conditions.

Seasonal and vertical variations in phytoplankton photosynthetic parameters and primary production in Suruga Bay, Japan

2021 ◽  
Author(s):  
Takashi Yoshikawa ◽  
Rumi Sohrin ◽  
Yumiko Obayashi ◽  
Hiroyuki Matsuura ◽  
Jun Nishikawa ◽  
...  
Keyword(s):  
Primary Production ◽  
Photosynthetic Parameters ◽  
Suruga Bay ◽  
Vertical Variations

scholarly journals Seasonal pattern of hepatitis E virus prevalence in swine in two different geographical areas of China

2013 ◽  
Vol 141 (11) ◽  
pp. 2403-2409 ◽  
Author(s):  
Y. H. LU ◽  
H. Z. QIAN ◽  
A. Q. HU ◽  
X. QIN ◽  
Q. W. JIANG ◽  
...  
Keyword(s):  
Hepatitis E Virus ◽  
Seasonal Pattern ◽  
Eastern China ◽  
Geographical Area ◽  
Hepatitis E ◽  
Southwestern China ◽  
Seasonal Patterns ◽  
Virus Prevalence ◽  
Swine Hepatitis ◽  
A Minor

SUMMARYWe studied seasonal patterns of swine hepatitis E virus (HEV) infection in China. From 2008 to 2011, 4200 swine bile specimens were collected for the detection of HEV RNA. A total of 92/2400 (3·83%) specimens in eastern China and 47/1800 (2·61%) specimens in southwestern China were positive for HEV. Seasonal patterns differing by geographical area were suggested. In eastern China, the major peak of HEV RNA prevalence was during March–April, with a minor peak during September–October, and a dip during July–August. In southwestern China, the peak was during September–October and the dip during March–April. The majority of subtype 4a cases (63/82, 76·83%) were detected in the first half of the year, while the majority of subtype 4b cases (26/29, 89·66%) were concentrated in the second half of the year, suggesting that different subtypes contribute to different peaks. Our results indicate that the distribution of HEV subtypes is associated with seasonal patterns.

Seasonal variation in births in rural East Pakistan

1972 ◽  
Vol 4 (1) ◽  
pp. 107-116 ◽  
Author(s):  
John Stoeckel ◽  
A. K. M. Alauddin Choudhury
Keyword(s):  
Seasonal Variation ◽  
Social Factors ◽  
Seasonal Pattern ◽  
Seasonal Patterns ◽  
First Order ◽  
Monthly Temperature ◽  
Monthly Distribution ◽  
Number Of Births

SummaryAn analysis of the monthly distribution of births in two areas of Matlab Thana, East Pakistan, indicates that there is a seasonal variation in births different from what would be expected by chance. The highest proportion of births occur in the last three months of a year and the lowest proportion between May and July. Investigation into some of the environmental and social factors which might contribute to the seasonal pattern revealed the following: mean minimum monthly temperature 9 months before birth was inversely related to the number of births; all occupations had seasonal patterns different from what would be expected by chance and the business and mill-and-office occupations had distributions significantly different from each other; the distribution of births for all pregnancy orders was different from chance and the distribution for first order pregnancies was significantly different from those for third and fourth or higher orders.

scholarly journals Distribution of guppies Poecilia reticulata (Peters, 1860) and Phalloceros caudimaculatus (Hensel, 1868) along a polluted stretch of the Paraíba do Sul River, Brazil

2009 ◽  
Vol 69 (1) ◽  
pp. 41-48 ◽  
Author(s):  
FG. Araújo ◽  
MG. Peixoto ◽  
BCT. Pinto ◽  
TP. Teixeira
Keyword(s):  
Environmental Conditions ◽  
Poecilia Reticulata ◽  
Condition Factor ◽  
Spatial Separation ◽  
Fishing Effort ◽  
Seasonal Patterns ◽  
Industrial Complex ◽  
Pregnant Females ◽  
Significant Difference ◽  
Paraíba Do Sul River

Cyprinodontiformes fishes (guppies) are widely distributed in Neotropical regions and use deteriorated microhabitats in rivers where few species can occur. This study was carried out in a stretch of the Paraíba do Sul River in bracketing a large urban-industrial complex. The aim was to assess eventual effects that the industrial complex could have on distribution of two closely related fish species of guppies, Phalloceros caudimaculatus and Poecilia reticulata. The area was divided into three zones: Z1, 40 km upriver of the major urban-industrial complex of Volta Redonda; Z2, just down river of the complex; and Z3, 30 km down river of the complex. Six sites (two in each zone) were sampled monthly between November 1998 and October 1999, using a standardized fishing effort with cast net throws, trays lifts and seine hauls, covering different microhabitats, that is, riffles, pools and the proximity of the river's margins. Poecilia reticulata was widely distributed, peaking at Z2, the most polluted area, while P. caudimaculatus showed the highest abundance at Z3, being almost absent in Z1. Both species occurred in high numbers throughout the year but they were scarce between April and June. Females outnumbered males for both species in most size classes and at all sites. Juveniles were more abundant than adults, with non-pregnant females outnumbering pregnant ones. Condition factor was always higher in males than females but only males P. reticulata showed significant difference among the three zones, with the highest values at Z2. The higher number of females confirms the expectation that these species can use very polluted areas and that availability of food provided by organic loads allowed their distribution all over the area. Although these two species have shown indication of spatial separation in the study area, their similar seasonal patterns of occurrence suggest that they respond in a similar way to changes in environmental conditions.

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>

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