scholarly journals New data on the distribution and abundance of Dendrolimus sibiricus (Tshetverikov, 1908) (Lepidoptera: Lasiocampidae) in the Komi Republic.

Author(s):  
Alexander Lukin

Abstract The Siberian silkworm (Dendrolimus sibiricus Tschetv.) is a defoliator pest that poses a significant threat to coniferous forest stands. Over the past decades, several large outbreaks of this species have occurred in Siberia (Russia), which has led to changes in forest ecosystems and an increase of expenses involved in reforestation. Adults capture new territories in the process of migration, therefore, a set of measures is needed to register the number and prevent further dispersal of the moth. One of methods of trapping is glue traps with synthetic pheromone. 16 district forestries located in the middle taiga subzone, with a total area of 151 850 hectares, were surveyed as a part of the phytosanitary monitoring of the Siberian silkworm in the Komi Republic (Russia). Analysis of 773 pheromone traps showed 414 males of the target species that were identified by their genitals. The highest indicators of catchability were found in three district forestries. Taking into account the results obtained, it was proposed to continue the monitoring using the pheromone traps, to survey more northern forest districts and to carry out subsequent searches for preimaginal stages of the silkworm in the forest districts of Priluzsky district. The study will be useful for predicting the further spread of the silkworm and for developing optimal containment and control of the pest.

2003 ◽  
Vol 3 (10) ◽  
pp. 926-931 ◽  
Author(s):  
Muhammad Faheem Mali . ◽  
Daud-ur-Rehman . ◽  
Mansoor Ahmed Bajwa . ◽  
Naveed Latif Lodhi . ◽  
Liaquat Ali . ◽  
...  

Insects ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 441
Author(s):  
Junheon Kim ◽  
Young Hak Jung ◽  
Sang-Myeong Lee

The pine wood nematode (PWN), Bursaphelenchus xylophilus, causes lethal pine wilt disease (PWD) in Asia and Europe and has become a serious threat to global pine forest ecosystems. In Korea, Monochamus saltuarius transmits PWN not only to Pinus densiflora, but also to Pinus koraiensis, which is widely distributed across eastern Asia. The diel rhythmicity of M. saltuarius in response to its aggregation pheromone was studied with the aim of providing reliable data for the prevention of PWD and control of Monochamus spp. Using a spray dispenser controlled with an electronic timer, M. saltuarius pheromone and attractants (PA) were sprayed to determine the diel rhythm of the response to PA. The spraying period was divided into four time periods: 05:00–11:00 (time period A), 11:00–17:00 (time period B), 17:00–23:00 (time period C), and 23:00–05:00 (time period D). The largest number of M. saltuarius was caught in time period B, followed by A, C, and D. It could be concluded that the flight activity of M. saltuarius in response to PA was diurnal. The results of this study improve the understanding of the behavioral biology of M. saltuarius, allowing for the development of pest management strategies to prevent the spread of PWN and control its vector.


2018 ◽  
Author(s):  
Gaolei Zhan ◽  
Younes Makoudi ◽  
Judicael Jeannoutot ◽  
Simon Lamare ◽  
Michel Féron ◽  
...  

Over the past decade, on-surface fabrication of organic nanostructures has been widely investigated for the development of molecular electronic devices, nanomachines, and new materials. Here, we introduce a new strategy to obtain alkyl oligomers in a controlled manner using on-surface radical oligomerisations that are triggered by the electrons/holes between the sample surface and the tip of a scanning tunnelling microscope. The resulting radical-mediated mechanism is substantiated by a detailed theoretical study. This electron transfer event only occurs when <i>V</i><sub>s</sub> < -3 V or <i>V</i><sub>s</sub> > + 3 V and allows access to reactive radical species under exceptionally mild conditions. This transfer can effectively ‘switch on’ a sequence leading to formation of oligomers of defined size distribution due to the on-surface confinement of reactive species. Our approach enables new ways to initiate and control radical oligomerisations with tunnelling electrons, leading to molecularly precise nanofabrication.


1997 ◽  
Vol 62 ◽  
Author(s):  
A. De Schrijver ◽  
L. Nachtergale ◽  
L. De Temmerman ◽  
J. M.F. Frechilla ◽  
S. Mussche ◽  
...  

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2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kwang-il Kim ◽  
Eunjeong Ji ◽  
Jung-yeon Choi ◽  
Sun-wook Kim ◽  
Soyeon Ahn ◽  
...  

AbstractWe analyzed the Korean National Health and Nutrition Examination Survey (KNHANES) database to determine the trends of hypertension treatment and control rate in Korea over the past 10 years. In addition, we tried to investigate the effect of chronic medical conditions on hypertension management. We investigated the hypertension prevalence, awareness, treatment, and control rate from 2008 to 2017. KNHANES, which uses a stratified multistage sampling design, is a cross-sectional, nationally representative survey conducted by the Korean government. A total of 59,282 adults (≥ 20 years) were included, which was representative of the total population of around 40 million Koreans per year. The mean age was 50.7 ± 16.4 years and 42.6% were male. The prevalence of hypertension, hypercholesterolemia, diabetes mellitus, and obesity significantly increased over the 10 years. During this period, the hypertension treatment and control rate significantly improved. Hypertension treatment rate was significantly lower in the younger age group compared to the older age group, but the control rate among the treated patients was not significantly different between age groups. The treatment and control rates of hypertension were higher in patients with multimorbidity, which implies that it has a favorable effect on the treatment and control of hypertension. Hypertension treatment and control rate have improved over the past 10 years. The higher treatment and control rate in patients with multimorbidity suggest that the more aggressive surveillance might be associated with the improvement of hypertension treatment and control rate in Korea.


Algorithms ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 174
Author(s):  
Wenxiao Zhao

The stochastic approximation algorithm (SAA), starting from the pioneer work by Robbins and Monro in 1950s, has been successfully applied in systems and control, statistics, machine learning, and so forth. In this paper, we will review the development of SAA in China, to be specific, the stochastic approximation algorithm with expanding truncations (SAAWET) developed by Han-Fu Chen and his colleagues during the past 35 years. We first review the historical development for the centralized algorithm including the probabilistic method (PM) and the ordinary differential equation (ODE) method for SAA and the trajectory-subsequence method for SAAWET. Then, we will give an application example of SAAWET to the recursive principal component analysis. We will also introduce the recent progress on SAAWET in a networked and distributed setting, named the distributed SAAWET (DSAAWET).


1969 ◽  
Vol 34 ◽  
pp. 368-384 ◽  
Author(s):  
Sebastian Payne

In recent discussions of the origins and process of animal domestication (Reed, 1961, Zeuner, 1963), both authors rely on two kinds of evidence: on the one hand, the present distributions and characteristics of the different breeds of whatever animal is being discussed, together with its feral and wild relatives, and, on the other hand, the past record, given by literary and pictorial sources and the bones from archaeological and geological sites. Increased recognition of the limitations of the past record, whether in the accuracy of the information it appears to give (as in the case of pictorial sources), or in the certainty of the deductions we are at present capable of drawing from it (this applies especially to the osteological record), has led these authors to argue mainly from the present situation, using the past record to confirm or amplify the existing picture.Arguing from the present, many hypotheses about the origins and process of domestication are available. The only test we have, when attempting to choose between these, lies in the direct evidence of the past record. The past record, it is freely admitted, is very fragmentary: the information provided by the present situation is more exact, ranges over a much wider field, and is more open to test and control. Nevertheless, the past record, however imperfect it is, is the only direct evidence we have about the process of domestication.


2014 ◽  
Vol 31 (5) ◽  
pp. 3-20 ◽  
Author(s):  
John Urry

Energy forms and their extensive scale are remarkably significant for the ways that societies are organized. This article shows the importance of how societies are ‘energized’ and especially the global growth of ‘fossil fuel societies’. Much social thought remains oblivious to the energy revolution realized over the past two to three centuries which set the ‘West’ onto a distinct trajectory. Energy is troubling for social thought because different energy systems with their ‘lock-ins’ are not subject to simple human intervention and control. Analyses are provided here of different fossil fuel societies, of coal and oil, with the latter enabling the liquid, mobilized 20th century. Consideration is paid to the possibilities of reducing fossil fuel dependence but it is shown how unlikely such a ‘powering down’ will be. The author demonstrates how energy is a massive problem for social theory and for 21st-century societies. Developing post-carbon theory and especially practice is far away but is especially urgent.


2003 ◽  
Vol 83 (5) ◽  
pp. 581-587 ◽  
Author(s):  
J. D. MacDonald ◽  
W. H. Hendershot

The concentrations of metals in soils are spatially heterogeneous and soil sampling carried out when studying metals in forest ecosystems is often inadequate. We examined the spatial variability of Cd, Cu, Mn, Ni, Pb and Zn in northern forest ecosystems on a transect with distance from two point source emitters with the goal of providing basic information about the distribution and variability of metals in these soils. Samples were taken under six sampling points at four depths from three experimental sites on each of the two transects. Soils were analysed for acid digestible metals, pH and organic carbon content. Standard deviation, coefficients of variation, mean and medians were analysed for each horizon of each site. It was observed that Cu and Mn variability is higher in closer proximity to the point source while the variability of Zn increased with decreasing soil pH. In Sudbury, emitted metals Ni and Cu accumulate together in soils, whereas in Rouyn-Noranda, with the exception of Cd and Zn, metal concentrations were not related in forest floors. Observations suggest that physical factors influencing where metals are deposited as well as the inherent variability in soil chemical characteristics, and the distance from the point source can all act together to result in high variability in soil metal concentrations in a single forest site. Sampling in the interest of relating vegetation metal concentrations or response to soil metals should be carried out on an individual plant basis with multiple samples taken for each individual. Soil samples taken at intervals of 1 to 1.7 m will provide relative error in estimating soil concentrations of 10% or 20%, respectively. Key words: Spatial variability, trace metals, podzolic soils, smelter emissions


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