Stem Radial Growth Is Negatively Related to Tree Defoliation and Damage in Conifers, Northern Italy

Although several manipulative experiments provided evidence for a negative effect of defoliation on tree growth, results from observational studies were less univocal. This may be due to the ability of observed defoliation to reflect the health status of individual trees, to the influence of site condition and to the amplitude of time window used for growth assessment. Here, we investigated the relationship between two tree health indicators (crown defoliation, damage symptoms) and annual (measured by tree-ring width on 69 Norway spruce trees) and periodical (5-year and 10-year diameter increments, 346 trees from five coniferous species) tree growth. Data originated from 14 (seven for tree rings) ICP Forests Level I plots in Trentino, northern Italy. Diameter, defoliation and damage were measured between 1997 and 2011 as part of the annual crown condition survey, while cores for tree-rings were collected on a sub-sample of trees in 2012. We carried out regression modeling combined with model selection in one-step (periodical data) and two-step (annual data) approaches, using moving averages for the annual data with varying time window widths. Our results indicated an overall negative correlation between defoliation and annual or periodical stem diameter growth. The relationship between defoliation and growth changes in relation to the time window considered, and becomes stronger when data are aggregated over longer time windows (>3 years), when also the occurrence of damage symptoms plays a significant role. The effect of the amplitude of the time windows for data aggregation is probably due to the mechanisms behind the defoliation-growth relationship, which may change according to the causal factors involved. In particular, when larger time windows are considered, short-term fluctuations are likely to be smoothed out, and more general patterns may emerge. We concluded that radial growth is significantly negatively related to defoliation, and this supports the use of defoliation as a rapid indicator for forest health and vitality.

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Impact of COVID-19 pandemic on HIV viremia: a single-center cohort study in northern Italy

AIDS Research and Therapy ◽

10.1186/s12981-021-00355-x ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Ilaria Izzo ◽

Canio Carriero ◽

Giulia Gardini ◽

Benedetta Fumarola ◽

Erika Chiari ◽

...

Keyword(s):

Time Window ◽

Time Windows ◽

Continuum Of Care ◽

Northern Italy ◽

Hiv Diagnosis ◽

Hiv Patients ◽

Before And After ◽

Missed Visits ◽

Hiv Continuum Of Care ◽

The Impact

Abstract Background Brescia Province, northern Italy, was one of the worst epicenters of the COVID-19 pandemic. The division of infectious diseases of ASST (Azienda Socio Sanitaria Territoriale) Spedali Civili Hospital of Brescia had to face a great number of inpatients with severe COVID-19 infection and to ensure the continuum of care for almost 4000 outpatients with HIV infection actively followed by us. In a recent manuscript we described the impact of the pandemic on continuum of care in our HIV cohort expressed as number of missed visits, number of new HIV diagnosis, drop in ART (antiretroviral therapy) dispensation and number of hospitalized HIV patients due to SARS-CoV-2 infection. In this short communication, we completed the previous article with data of HIV plasmatic viremia of the same cohort before and during pandemic. Methods We considered all HIV-patients in stable ART for at least 6 months and with at least 1 available HIV viremia in the time window March 01–November 30, 2019, and another group of HIV patients with the same two requisites but in different time windows of the COVID-19 period (March 01–May 31, 2020, and June 01–November 30, 2020). For patients with positive viremia (PV) during COVID-19 period, we reported also the values of viral load (VL) just before and after PV. Results: the percentage of patients with PV during COVID-19 period was lower than the previous year (2.8% vs 7%). Only 1% of our outpatients surely suffered from pandemic in term of loss of previous viral suppression. Conclusions Our efforts to limit the impact of pandemic on our HIV outpatients were effective to ensure HIV continuum of care.

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Drought Enhances the Role of Competition in Mediating the Relationship between Tree Growth and Climate in Semi-Arid Areas of Northwest China

Forests ◽

10.3390/f10090804 ◽

2019 ◽

Vol 10 (9) ◽

pp. 804 ◽

Cited By ~ 3

Author(s):

Kanglong Lu ◽

Ning Chen ◽

Cankun Zhang ◽

Xiaoxue Dong ◽

Changming Zhao

Keyword(s):

Climate Variability ◽

Water Use Efficiency ◽

Water Use ◽

Tree Growth ◽

Radial Growth ◽

Intrinsic Water Use Efficiency ◽

Adverse Weather ◽

Significant Difference ◽

Use Efficiency ◽

The Relationship

Climate variability can exert a powerful impact on biotic competition, but past studies have focused largely on short-lived species, with a lack of attention to long-lived species such as trees. Therefore, there is a need to evaluate how competition regulates the climate-growth relationship in mature trees. We sampled the dominant tree species, Picea wilsonii Mast., on Xinglong Mountain, China, and studied the above issues by analyzing the relationship between tree radial growth, precipitation, and competition. In relatively wet years (precipitation > average), there was no significant difference in climate sensitivity between different competition classes. However, trees suffering from highly competitive stress were more sensitive to climate variability in all years, and particularly in the subset of years that was relatively drought (precipitation < average). These results suggest that competition enhances its ability to regulate tree growth response to climate variability in adverse weather conditions. Competition for resources between trees was asymmetrical, and an increase in height could give trees a disproportionate benefit. Thus, at trunk-level, both basal area incremental growth and intrinsic water-use efficiency of trees subjected to low competitive stress were significantly higher than trees that are subjected to highly competitive stress. Although the intrinsic water-use efficiency of trees under highly competitive stress increased more rapidly as the drought level increases, this did not change the fact that the radial growth of them declined more. Our research is valuable for the development of individual-tree growth models and advances our understanding for forest management under global climate change.

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EXPRESS: Influence of Time to Endovascular Stroke Treatment on Outcomes in the Early versus Extended Window Paradigms

International Journal of Stroke ◽

10.1177/17474930211006304 ◽

2021 ◽

pp. 174749302110063

Author(s):

Raul Nogueira ◽

Tudor G Jovin ◽

Diogo C. Haussen ◽

Rishi Gupta ◽

ashutosh Jadhav ◽

...

Keyword(s):

Functional Disability ◽

Time Window ◽

Time Windows ◽

Extended Time ◽

Primary Analysis ◽

Anterior Circulation ◽

Time To Treatment ◽

Stroke Treatment ◽

The Impact ◽

The Relationship

Background The effect of time from stroke onset to thrombectomy in the extended time window remains poorly characterized. Aim We aimed to analyze the relationship between time to treatment and clinical outcomes in the early versus extended time windows. Methods Proximal anterior circulation occlusion patients from a multicentric prospective registry were categorized into early (â¤6-hours) or extended (>6-24-hours) treatment window. Patients with baseline NIHSSâ¥10 and intracranial ICA or MCA-M1-segment occlusion and pre-morbid mRS0-1 (âDAWN-likeâ cohort) served as the population for the primary analysis. The relationship between time to treatment and 90-day mRS, analyzed in ordinal (mRS shift) and dichotomized (good outcome, mRS0-2) fashion, was compared within and across the extended and early-windows. Results A total of 1603 out of 2008 patients qualified. Despite longer time to treatment (9[7-13.9]vs.3.4[2.5-4.3] hours,p<0.001), extended-window patients (n=257) had similar rates of symptomatic intracranial hemorrhage (0.8%vs.1.7%,p=0.293) and 90-day-mortality (10.5%vs.9.6%,p=0.714) with only slightly lower rates of 90-day good outcomes (50.4%vs.57.6%,p=0.047) versus early-window patients (n=709). Time to treatment was associated with 90-day disability in both ordinal (aOR,â¥1-point mRS shift:0.75;95%CI[0.66-0.86],p<0.001) and dichotomized (aOR,mRS0-2:0.73;95%CI[0.62-0.86],p<0.001) analyses in the early- but not in the extended-window (aOR, mRS shift:0.96;95%CI[0.90-1.02],p=0.15; aOR,mRS0-2:0.97;95%CI[0.90-1.04],p=0.41). Early-window patients had significantly lower 90-day functional disability (aOR, mRS shift:1.533;95%CI[1.138-2.065],p=0.005) and a trend towards higher rates of good outcomes (aOR,mRS0-2:1.391;95%CI[0.972-1.990],p=0.071). Conclusions The impact of time to thrombectomy on outcomes appears to be time dependent with a steep influence in the early followed by a less significant plateau in the extended window. However, every effort should be made to shorten treatment times regardless of ischemia duration.

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Tree rings of Pinus nigra from the Vienna basin region (Austria) show evidence of change in climatic sensitivity in the late 20th century

Canadian Journal of Forest Research ◽

10.1139/x07-189 ◽

2008 ◽

Vol 38 (4) ◽

pp. 744-759 ◽

Cited By ~ 35

Author(s):

Sofia Leal ◽

Derek Eamus ◽

Michael Grabner ◽

Rupert Wimmer ◽

Paolo Cherubini

Keyword(s):

Growth Rate ◽

20Th Century ◽

Tree Rings ◽

Tree Growth ◽

Water Availability ◽

Summer Precipitation ◽

Pinus Nigra ◽

Vienna Basin ◽

Late 20Th Century ◽

The Relationship

The width of tree rings of Pinus nigra Arn. trees growing near the ecological limits for the species, in the Vienna basin, Austria, showed a strong and positive correlation with spring–summer precipitation, indicating a dependence of growth on water availability during the growing season. During the late 20th century, tree rings grew wider than expected given the predicted relationship between rainfall and growth rate observed in the early 20th century. This resulted in models of the relationship between climate and growth rate systematically overestimating the total spring–summer (April–July) precipitation over the last half of the 20th century. Analysis of the temporal stability of the relationship between tree growth and climate variables shows a decrease in the sensitivity of the growth of tree rings to spring–summer precipitation towards the end of the 20th century. This change in sensitivity suggests that tree growth was no longer primarily dependent on water availability. We propose that there was an improvement in water-use efficiency arising from a stimulation of photosynthesis and declining stomatal conductance as a consequence of the increasing CO2 concentration in the atmosphere and that this effect was enhanced by a relatively high input of N due to the proximity of N emission sources.

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How effectively do drought indices capture health outcomes? An investigation from rural Australia

Weather Climate and Society ◽

10.1175/wcas-d-20-0119.1 ◽

2021 ◽

Author(s):

Emma Austin ◽

Anthony S. Kiem ◽

Jane Rich ◽

David Perkins ◽

Brian Kelly

Keyword(s):

Time Window ◽

Empirical Studies ◽

Time Windows ◽

Drought Indices ◽

Drought Duration ◽

South Wales ◽

The Individual ◽

Global Threat ◽

The Impact ◽

The Relationship

AbstractDrought is a global threat to public health. Increasingly, the impact of drought on mental health and wellbeing is being recognised. This paper investigates the relationship between drought and wellbeing to determine which drought indices most effectively capture wellbeing outcomes. A thorough understanding of the relationship between drought and wellbeing must consider the: (i) three aspects of drought (duration, frequency and magnitude); (ii) different types of drought (e.g. meteorological, agricultural, etc.); and (iii) the individual context of specific locations, communities and sectors. For this reason, we used a variety of drought types, drought indices, and time windows to identify the thresholds for wet and dry epochs that enhance and suppress impacts to wellbeing. Four postcodes in New South Wales (NSW), Australia are used as case studies in the analysis to highlight the spatial variability in the relationship between drought and wellbeing. The results demonstrate that the relationship between drought indices and wellbeing outcomes differs temporally, spatially and according to drought type. This paper objectively tests the relationship between commonly used drought indices and wellbeing outcomes to establish if current methods of quantifying drought effectively capture wellbeing outcomes. For funding, community programs and interventions to result in successful adaptation, it is essential to critically choose which drought index, time window and wellbeing outcome to use in empirical studies. The uncertainties associated with these relationships must be accounted for and it must also be realized that results will differ based on these decisions.

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The Nexus between Financial Development and Human Development: The Case of Developing Countries

Journal of Emerging Economies and Islamic Research ◽

10.24191/jeeir.v8i2.8735 ◽

2020 ◽

Vol 8 (2) ◽

pp. 68

Author(s):

Bilgehan Tekin

Keyword(s):

Developing Countries ◽

Private Sector ◽

Human Development ◽

Financial Development ◽

Cointegration Analysis ◽

Annual Data ◽

Causality Analysis ◽

Development Index ◽

Development Levels ◽

The Relationship

The purpose of this study to examine the relationship between financial development and human development in the health and welfare dimensions of developing countries. This study aims to determine whether the financial developments of the countries have an effect on the basic human development of the individuals and whether human development indicators have an impact on financial development. In this study, the relationship between financial development and human development has been tried to be revealed by using data obtained from developing countries. Financial development levels of the countries were measured with the developed financial development index. The index is calculated by using M3 / GDP, private sector loans / GDP and loans to banks from private sector / GDP ratios. The human development index is calculated by considering various health indicators and GNP per capita. The data includes annual data for the period 1970-2016. Pedroni and Kao cointegration analysis and Dumitrescu & Hurlin panel causality analysis were performed in the study. According to the results of the study, the cointegration relationship was determined between the two variables. There is also a two-way causality between the variables.

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Reply to “Comment on ‘The Impact of Recent Forcing and Ocean Heat Uptake Data on Estimates of Climate Sensitivity’”

Journal of Climate ◽

10.1175/jcli-d-18-0669.1 ◽

2020 ◽

Vol 33 (1) ◽

pp. 397-404 ◽

Cited By ~ 1

Author(s):

Nicholas Lewis ◽

Judith Curry

Keyword(s):

Time Windows ◽

Internal Variability ◽

Historical Record ◽

Cmip5 Models ◽

Temperature Record ◽

Ocean Heat Uptake ◽

Transient Climate Response ◽

Total Uncertainty ◽

The Impact ◽

The Relationship

AbstractCowtan and Jacobs assert that the method used by Lewis and Curry in 2018 (LC18) to estimate the climate system’s transient climate response (TCR) from changes between two time windows is less robust—in particular against sea surface temperature bias correction uncertainty—than a method that uses the entire historical record. We demonstrate that TCR estimated using all data from the temperature record is closely in line with that estimated using the LC18 windows, as is the median TCR estimate using all pairs of individual years. We also show that the median TCR estimate from all pairs of decade-plus-length windows is closely in line with that estimated using the LC18 windows and that incorporating window selection uncertainty would make little difference to total uncertainty in TCR estimation. We find that, when differences in the evolution of forcing are accounted for, the relationship over time between warming in CMIP5 models and observations is consistent with the relationship between CMIP5 TCR and LC18’s TCR estimate but fluctuates as a result of multidecadal internal variability and volcanism. We also show that various other matters raised by Cowtan and Jacobs have negligible implications for TCR estimation in LC18.

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Comparison of the Radial Growth Response of Picea crassifolia to Climate Change in Different Regions of the Central and Eastern Qilian Mountains

Forests ◽

10.3390/f12081015 ◽

2021 ◽

Vol 12 (8) ◽

pp. 1015

Author(s):

Xuan Wu ◽

Liang Jiao ◽

Dashi Du ◽

Changliang Qi ◽

Ruhong Xue

Keyword(s):

Climate Change ◽

Tree Growth ◽

Central Region ◽

Radial Growth ◽

Growing Season ◽

Qilian Mountains ◽

Growth Patterns ◽

Total Precipitation ◽

Picea Crassifolia ◽

The Qilian Mountains

It is important to explore the responses of radial tree growth in different regions to understand growth patterns and to enhance forest management and protection with climate change. We constructed tree ring width chronologies of Picea crassifolia from different regions of the Qilian Mountains of northwest China. We used Pearson correlation and moving correlation to analyze the main climate factors limiting radial growth of trees and the temporal stability of the growth–climate relationship, while spatial correlation is the result of further testing the first two terms in space. The conclusions were as follows: (1) Radial growth had different trends, showing an increasing followed by a decreasing trend in the central region, a continuously increasing trend in the eastern region, and a gradually decreasing trend in the isolated mountain. (2) Radial tree growth in the central region and isolated mountains was constrained by drought stress, and tree growth in the central region was significantly negatively correlated with growing season temperature. Isolated mountains showed a significant negative correlation with mean minimum of growing season and a significant positive correlation with total precipitation. (3) Temporal dynamic responses of radial growth in the central region to the temperatures and SPEI (the standardized precipitation evapotranspiration index) in the growing season were unstable, the isolated mountains to total precipitation was unstable, and that to SPEI was stable. The results of this study suggest that scientific management and maintenance plans of the forest ecosystem should be developed according to the response and growth patterns of the Qinghai spruce to climate change in different regions of the Qilian Mountains.

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How Does Radial Growth of Water-Stressed Populations of European Beech (Fagus sylvatica L.) Trees Vary under Multiple Drought Events?

Forests ◽

10.3390/f12020129 ◽

2021 ◽

Vol 12 (2) ◽

pp. 129

Author(s):

Tamalika Chakraborty ◽

Albert Reif ◽

Andreas Matzarakis ◽

Somidh Saha

Keyword(s):

Soil Water ◽

Fagus Sylvatica ◽

Tree Growth ◽

Radial Growth ◽

Basal Area ◽

European Beech ◽

Canopy Openness ◽

Fagus Sylvatica L ◽

The Impact ◽

Neighborhood Competition

European beech (Fagus sylvatica L.) trees are becoming vulnerable to drought, with a warming climate. Existing studies disagree on how radial growth varies in European beech in response to droughts. We aimed to find the impact of multiple droughts on beech trees’ annual radial growth at their ecological drought limit created by soil water availability in the forest. Besides, we quantified the influence of competition and canopy openness on the mean basal area growth of beech trees. We carried out this study in five near-natural temperate forests in three localities of Germany and Switzerland. We quantified available soil water storage capacity (AWC) in plots laid in the transition zone from oak to beech dominated forests. The plots were classified as ‘dry’ (AWC < 60 mL) and ‘less-dry’ (AWC > 60 mL). We performed dendroecological analyses starting from 1951 in continuous and discontinuous series to study the influence of climatic drought (i.e., precipitation-potential evapotranspiration) on the radial growth of beech trees in dry and less-dry plots. We used observed values for this analysis and did not use interpolated values from interpolated historical records in this study. We selected six drought events to study the resistance, recovery, and resilience of beech trees to drought at a discontinuous level. The radial growth was significantly higher in less-dry plots than dry plots. The increase in drought had reduced tree growth. Frequent climatic drought events resulted in more significant correlations, hence, increased the dependency of tree growth on AWC. We showed that the recovery and resilience to climatic drought were higher in trees in less-dry plots than dry plots, but it was the opposite for resistance. The resistance, recovery, and resilience of the trees were heterogeneous between the events of drought. Mean growth of beech trees (basal area increment) were negatively impacted by neighborhood competition and positively influenced by canopy openness. We emphasized that beech trees growing on soil with low AWC are at higher risk of growth decline. We concluded that changes in soil water conditions even at the microsite level could influence beech trees’ growth in their drought limit under the changing climate. Along with drought, neighborhood competition and lack of light can also reduce beech trees’ growth. This study will enrich the state of knowledge about the ongoing debate on the vulnerability of beech trees to drought in Europe.

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A hybrid ant colony algorithm based on multiple strategies for the vehicle routing problem with time windows

Complex & Intelligent Systems ◽

10.1007/s40747-021-00401-1 ◽

2021 ◽

Author(s):

Hongguang Wu ◽

Yuelin Gao ◽

Wanting Wang ◽

Ziyu Zhang

Keyword(s):

Vehicle Routing ◽

Vehicle Routing Problem ◽

Ant Colony Algorithm ◽

Time Window ◽

Time Windows ◽

Ant Colony ◽

Routing Problem ◽

Multiple Strategies ◽

Hard Time ◽

Mutation Operation

AbstractIn this paper, we propose a vehicle routing problem with time windows (TWVRP). In this problem, we consider a hard time constraint that the fleet can only serve customers within a specific time window. To solve this problem, a hybrid ant colony (HACO) algorithm is proposed based on ant colony algorithm and mutation operation. The HACO algorithm proposed has three innovations: the first is to update pheromones with a new method; the second is the introduction of adaptive parameters; and the third is to add the mutation operation. A famous Solomon instance is used to evaluate the performance of the proposed algorithm. Experimental results show that HACO algorithm is effective against solving the problem of vehicle routing with time windows. Besides, the proposed algorithm also has practical implications for vehicle routing problem and the results show that it is applicable and effective in practical problems.

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