Oscillation, synchrony, and multi-factor patterns between cereal aphids and parasitoid populations in southern Brazil

2021 ◽  
pp. 1-8
Author(s):  
Eduardo Engel ◽  
Douglas Lau ◽  
Wesley A. C. Godoy ◽  
Mauricio P. B. Pasini ◽  
José B. Malaquias ◽  
...  
Keyword(s):  
Neotropical Region ◽  
Meteorological Variables ◽  
Regulatory Function ◽  
Cereal Aphids ◽  
Annual Peak ◽  
Spring Transition ◽  
Favorable Temperature ◽  
Positive Effect ◽  
Second Peak

Abstract In different parts of the world, aphid populations and their natural enemies are influenced by landscapes and climate. In the Neotropical region, few long-term studies have been conducted, maintaining a gap for comprehension of the effect of meteorological variables on aphid population patterns and their parasitoids in field conditions. This study describes the general patterns of oscillation in cereal winged aphids and their parasitoids, selecting meteorological variables and evaluating their effects on these insects. Aphids exhibit two annual peaks, one in summer–fall transition and the other in winter-spring transition. For parasitoids, the highest annual peak takes place during winter and a second peak occurs in winter–spring transition. Temperature was the principal meteorological regulator of population fluctuation in winged aphids and parasitoids during the year. The favorable temperature range is not the same for aphids and parasitoids. For aphids, temperature increase resulted in population growth, with maximum positive effect at 25°C. Temperature also positively influenced parasitoid populations, but the growth was asymptotic around 20°C. Although rainfall showed no regulatory function on aphid seasonality, it influenced the final number of insects over the year. The response of aphids and parasitoids to temperature has implications for trophic compatibility and regulation of their populations. Such functions should be taken into account in predictive models.

Crop rotations with clover and their productivity

2020 ◽  
Author(s):  
Ol'ga Gladysheva ◽  
Oksana Artyuhova ◽  
Vera Svirina
Keyword(s):  
Forest Soil ◽  
Crop Rotation ◽  
Gray Forest Soil ◽  
Arable Land ◽  
Perennial Grasses ◽  
Crop Rotations ◽  
Field Crop ◽  
Pure Steam ◽  
Positive Effect

The results of long-term research in experiments with crop rotations with different clover saturation are presented. It is shown that the cluster has a positive effect on the main indicators of vegetation of dark-gray forest soil. The introduction of two fields of perennial grasses into the six-field crop rotation significantly increases both the humus reserves and increases the productivity of arable land by 1.5–2 times compared to the crop rotation with a field of pure steam.

The depressing (negative) effect of oestradiol benzoate on the in vitro secretion of LH and FSH by the pituitary gland of the LRH-pretreated long-term ovariectomized rat changes into the augmentative (positive) effect after discontinuation of the LRH-pretreatment

1985 ◽  
Vol 110 (3) ◽  
pp. 329-337 ◽  
Author(s):  
G. A. Schuiling ◽  
H. Moes ◽  
T. R. Koiter
Keyword(s):  
Depressing Effect ◽  
Ovx Rats ◽  
Gonadotrophin Secretion ◽  
Oestradiol Benzoate ◽  
Negative Effect ◽  
Positive Effect ◽  
Perifusion System

Abstract. The effect of pretreatment in vivo with oestradiol benzoate on in vitro secretion of LH and FSH was studied in long-term ovariectomized (OVX) rats both at the end of a 5-day continuous in vivo pretreatment with LRH and 4-days after cessation of such LRH pretreatment. Rats were on day 0 sc implanted with osmotic minipumps which released LRH at the rate of 250 ng/h. Control rats were implanted with a piece of silicone elastomer with the dimensions of a minipump. On days 2 and 4 the rats were injected with either 3 μg EB or with oil. On day 5 part of the rats were decapitated and the in vitro autonomous (i.e. non-LRH-stimulated) and 'supra-maximally' LRHstimulated release of LH and FSH was studied using a perifusion system. From other rats the minipumps were removed on day 5 and perifusion was performed on day 9. On the 5th day of the in vivo LRH pretreatment the pituitary LH/FSH stores were partially depleted; the pituitaries of the EB-treated rats more so than those of the oil-injected rats. EB alone had no significant effect on the content of the pituitary LH- and FSH stores. On day 9, i.e. 4 days after removal of the minipumps, the pituitary LH and FSH contents had increased in both the oil- and the EB injected rats, but had not yet recovered to control values. In rats not subjected to the 5-days pretreatment with LRH EB had a positive effect on the supra-maximally LRH-stimulated secretion of LH and FSH as well as on the non-stimulated secretion of LH. EB had no effect on the non-stimulated secretion of FSH. After 5 days of in vivo pretreatment with LRH only, the in vitro non-stimulated and supra-maximally LRH-stimulated secretion of both LH and FSH were strongly impaired, the effect correlating well with the LRH-induced depletion of the pituitary LH/FSH stores. In such LRH-pretreated rats EB had on day 5 a negative effect on the (already depressed) LRH-stimulated secretion of LH (not on that of FSH). EB had no effect on the non-stimulated LH/FSH secretion. It could be demonstrated that the negative effect of the combined LRH/EB pretreatment was mainly due to the depressing effect of this treatment on the pituitary LH and FSH stores: the effect of oestradiol on the pituitary LRH-responsiveness (release as related to pituitary gonadotrophin content) remained positive. In LRH-pretreated rats, however, this positive effect of EB was smaller than in rats not pretreated with LRH. Four days after removal of the minipumps there was again a positive effect of EB on the LRH-stimulated secretion of LH and FSH as well as on the non-stimulated secretion of LH. The positive effect of EB on the pituitary LRH-responsiveness was as strong as in rats which had not been exposed to exogenous LRH. The non-stimulated secretion of FSH was again not affected by EB. The results demonstrate that the effect of EB on the oestrogen-sensitive components of gonadotrophin secretion consists of two components: an effect on the pituitary LRH-responsiveness proper, and an effect on the pituitary LH/FSH stores. The magnitude of the effect of EB on the LRH-responsiveness is LRH dependent: it is very weak (almost zero) in LRH-pretreated rats, but strong in rats not exposed to LRH as well as in rats of which the LRH-pretreatment was stopped 4 days previously. Similarly, the effect of EB on the pituitary LH and FSH stores is LRH-dependent: in the absence of LRH, EB has no influence on the contents of these stores, but EB can potentiate the depleting effect of LRH on the LH/FSH-stores. Also this effect disappear after cessation of the LRH-pretreatment.

Удобрение огурца в Западной Сибири

2018 ◽  
Author(s):  
Т.А. Кuznetsova ◽  
N.А. Коlpakov
Keyword(s):  
Organic Fertilizers ◽  
Control Variant ◽  
Positive Effect ◽  
Different Doses

Показано, что длительное применение как минеральных, так и органических удобрений в различных дозах и сочетаниях положительно влияет на урожайность огурца. Установлено, что в условиях 14-й ротации урожайность на всех вариантах опыта была выше, чем на контрольном варианте и составила 16,4–22,3 т/га, против 16,0 т/га в контроле.The authors show that the long-term use of both mineral and organic fertilizers in different doses and combinations has a positive effect on the yield of cucumber. It was found that under 14 rotation conditions the yield on all variants of the experiment was higher than on the control variant and amounted to 16.4–22.3 t/ha, against 16.0 t/ha on the control.

Possibilities and prospects of conservative therapy for endometriosis, as a chronical progressing disease (review of literature)

GYNECOLOGY ◽  
2020 ◽  
Vol 22 (1) ◽  
pp. 14-18 ◽  
Author(s):  
Tatyana Yu. Pestrikova ◽  
Elena A. Yurasova ◽  
Igor V. Yurasov
Keyword(s):  
Quality Of Life ◽  
Abnormal Uterine Bleeding ◽  
Modern Medicine ◽  
Reproductive Age ◽  
Aim Analysis ◽  
Scientific Publications ◽  
Terra Incognita ◽  
Positive Effect

Relevance. Endometriosis is a common gynecological disease that affects up to 10% of women of reproductive age worldwide and is the main cause of pain and infertility. Endometriosis is a disease, although it has been known for a long time, nevertheless, in many ways it represents terra incognita for modern medicine. Aim. Analysis of literature on the feasibility of long-term and the use of the drug dienogest 2 mg (Vizanne), which has a positive effect on the quality of life of patients with endometriosis. Materials and methods. To write this review, a search was made for domestic and foreign publications in Russian and international search engines (PubMed, eLibrary, etc.) over the past 13 years. The review included articles from peer-reviewed literature. Results. The review presents data on the difficulties of verifying the diagnosis of endometriosis due to a combination of this pathology with pain, infertility, abnormal uterine bleeding. The pathogenesis of the origin of endometriosis-associated pain is presented. The efficacy of the use of the drug dienogest (Vizanne), which has a powerful antiproliferative effect that reduces the main symptoms of endometriosis (pain, bleeding), is substantiated. The expediency of long-term and safe use of the drug dienogest (Vizanne), which has a positive effect on the quality of life of patients with endometriosis, has been proved. Conclusions. Numerous scientific publications confirm the feasibility of prolonged use of the drug dienogest (Vizanne), to achieve remission during endometriosis.

PENGARUH INFRASTRUKTUR SECARA SPASIAL TERHADAP KONVERGENSI PERTUMBUHAN EKONOMI DI INDONESIA

INFO ARTHA ◽  
2017 ◽  
Vol 1 ◽  
pp. 17-28
Author(s):  
Anisa Fahmi
Keyword(s):  
Economic Growth ◽  
Regional Economics ◽  
Developed Countries ◽  
Road Infrastructure ◽  
Long Run ◽  
Catch Up ◽  
The Developed Countries ◽  
Positive Effect ◽  
Neoclassical Growth Theory

Motivated by inter-regional disparities condition that occurs persistently, this study examines the Indonesian economy in the long run in order to know whether it tends to converge or diverge. This convergence is based on the Solow Neoclassical growth theory assuming the existence of diminishing returns to capital so that when the developed countries reach steady state conditions, developing countries will continuously grow up to 'catch-up' with developed countries. Based on regional economics perspective, each region can not be treated as a stand-alone unit,therefore, this study also focuses on the influence of spatial dependency and infrastructure. Economical and political situations of a region will influence policy in that region which will also have an impact to the neighboring regions. The estimation results of spatial cross-regressive model using fixed effect method consistently confirmed that the Indonesian economy in the long term will likely converge with a speed of 8.08 percent per year. Other findings are road infrastructure has a positive effect on economic growth and investment and road infrastructure are spatially showed a positive effect on economic growth. In other words, the investment and infrastructure of a region does not only affect the economic growth of that region but also to the economy of the contiguous regions. 

scholarly journals Implementation Intentions to Reduce Smoking: A Systematic Review of the Literature

2020 ◽  
Author(s):  
Charlotte J Hagerman ◽  
Rebecca K Hoffman ◽  
Sruthi Vaylay ◽  
Tonya Dodge
Keyword(s):  
Systematic Review ◽  
Implementation Intentions ◽  
Experimental Studies ◽  
Implementation Intention ◽  
Promising Tool ◽  
Current Systematic Review ◽  
Long Term Follow Up ◽  
Positive Effect

Abstract Implementation intentions are a goal-setting technique in which an individual commits to perform a particular behavior when a specific context arises. Recently, researchers have begun studying how implementation intention (II) interventions can facilitate antismoking efforts. The current systematic review synthesized results of experimental studies that tested the effect of an II intervention on smoking cognitions and behavior. Of 29 reviewed articles, 11 studies met inclusion criteria. Nine studies (81.8%) tested an II intervention as a cessation tool for current smokers, whereas two tested II interventions as a tool to prevent smoking among predominantly nonsmoking adolescents. A majority of the studies (66.7%) testing II interventions as a cessation tool reported a positive effect on cessation at long-term follow-up. Of the two studies testing II interventions as a tool for prevention, one study found a positive effect on long-term follow-up. Methodology varied between the studies, highlighting the discrepancies between what researchers consider “implementation intentions” to be. II interventions are a promising tool for antismoking efforts, but more research is necessary to determine the best methodology and the populations for whom this intervention will be most effective. Implications Brief, free, and easily scalable, II interventions to prevent smoking are highly attractive for antismoking efforts. This review outlines the circumstances under which II interventions have demonstrated effectiveness in helping people resist smoking cigarettes. We illuminate gaps in the existing literature, limitations, methodological discrepancies between studies, and areas for future study.

scholarly journals The Demerger Impact upon Sustainable Development of Economic Entities: Evidence from Romania

2021 ◽  
Vol 13 (15) ◽  
pp. 8316
Author(s):  
Camelia Mirela Baba ◽  
Constantin Duguleană ◽  
Marius Sorin Dincă ◽  
Liliana Duguleană ◽  
Gheorghița Dincă
Keyword(s):  
Sustainable Development ◽  
Business Strategies ◽  
The Sustainable Development ◽  
Ex Post ◽  
Before And After ◽  
Almost All ◽  
The Impact ◽  
Profitability Ratios ◽  
Positive Effect

The Covid-19 induced economic crisis has significantly affected almost all businesses from nearly every sector, causing severe financial problems, lack of cash assets, and decrease of revenues. In this context, the economic entities were forced to look for adjustment and rescue solutions of their activities. One possible solution for the recovery and reorganization of economic entities’ activities is demerger. This paper evaluates the impact of demerger upon the sustainable development of economic entities in terms of economic efficiency and financial performances. To achieve this goal, a statistical analysis of profitability ratios before and after the demerger, as well as a structural analysis of 268 demerger projects for the April 2012–April 2021 period, were performed. The results attest there are no significant differences between the ex-ante and ex-post financial performances. However, demerger seems to have a positive effect upon analyzed companies helping them to overcome economic hardships, rethink their business strategies, and continue their activity in the medium and long-term time horizon.

Crevice Corrosion Studies on Corrosion Resistant Alloys in Stagnant Natural Seawater

2012 ◽  
Vol 610-613 ◽  
pp. 276-279
Author(s):  
Laura L. Machuca ◽  
Stuart I. Bailey ◽  
Rolf Gubner
Keyword(s):  
Crevice Corrosion ◽  
Corrosion Potential ◽  
Natural Seawater ◽  
Corrosion Resistant ◽  
Testing Procedures ◽  
Corrosion Studies ◽  
Long Term Performance ◽  
Term Performance ◽  
Positive Effect

Crevice corrosion (CC) was investigated for a number of selected corrosion resistant alloys in natural seawater containing microorganisms for up to 18 months under stagnant conditions. Experimental controls consisted of tests in natural seawater filtered in accordance with hydrostatic testing procedures. The corrosion potential of alloys was monitored throughout exposure and corrosion was evaluated by weight loss and 3D optical microscopy. CC was initiated on several alloys and corrosion rates in time indicated a positive effect of seawater filtration on the long-term performance of the alloys. Microbial adhesion, as indicated by fluorescence microscopy, occurred mainly outside the crevice and differed according to the nature of the substratum surface.

Long-term data indicates that supplementary food enhances the number of breeding pairs in a Cape Vulture Gyps coprotheres colony

2016 ◽  
Vol 27 (1) ◽  
pp. 140-152 ◽  
Author(s):  
DANA G. SCHABO ◽  
SONJA HEUNER ◽  
MICHAEL V. NEETHLING ◽  
SASCHA RÖSNER ◽  
ROGER UYS ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Breeding Success ◽  
Food Sources ◽  
Breeding Colony ◽  
Supplementary Food ◽  
Adequate Food ◽  
Vulture Conservation ◽  
Positive Effect ◽  
Term Data

SummaryThe number of vultures is declining in many parts of the world due to numerous threats, such as poisoning and collisions with power-lines as well as the lack of adequate food sources. Vulture restaurants, i.e. supplementary feeding stations, have become a widespread conservation tool aimed at supporting vulture colonies. However, it is poorly understood how vulture restaurants influence population dynamics and whether they affect breeding success of vulture populations. We used a 12-year dataset from a breeding colony of the Cape Vulture Gyps coprotheres and a nearby vulture restaurant in South Africa to investigate the effect of supplementary food on population dynamics and breeding success. We found a significantly positive effect of supplementary food during the nest-building stage on the number of breeding pairs. However, breeding success, i.e. the proportion of successful nests, did not depend on supplementary food during the incubation and rearing stage. Especially during the critical rearing stage, the amount of food supplied might not have been sufficient to meet food demands of the colony. Still, our results indicate that carefully managed vulture restaurants might stabilise vulture colonies and can therefore aid vulture conservation.

scholarly journals Effects of Organic Energy Crop Rotations and Fertilisation with the Liquid Digestate Phase on Organic Carbon in the Topsoil

Agronomy ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1393
Author(s):  
Karin S. Levin ◽  
Karl Auerswald ◽  
Hans Jürgen Reents ◽  
Kurt-Jürgen Hülsbergen
Keyword(s):  
Organic Carbon ◽  
Organic Farming ◽  
Biogas Production ◽  
Crop Rotations ◽  
Energy Crop ◽  
Long Term Effects ◽  
Liquid Digestate ◽  
Organic Farmers ◽  
Positive Effect

Combining organic farming and biogas production from agricultural feedstocks has been suggested as a way of achieving carbon (C) neutrality in Europe. However, as the long-term effects of C removal for methane production on soil organic carbon (SOC) are unclear, organic farmers in particular have questioned whether farm biogas production will have a positive effect on soil fertility. Eight years of data from an organic long-term field trial involving digestate fertilisation and various crop rotations (CRs) with differing proportions of clover-grass leys were used to calculate C inputs based on the CANDY model, and these modelled changes compared with measured changes in SOC content (SOCc) over the same period. Measured SOCc increased by nearly 20% over the eight years. Digestate fertilisation significantly increased SOCc. Fertilised plots with the highest proportion of clover-grass in the CR had the highest SOCc. The C inputs from clover-grass leys, even if they only made up 25% of the CR, were high enough to increase SOCc, even with the removal of all aboveground biomass and without fertilisation. Our results show that biogas production based on clover-grass leys could be an important part of sustainable farming, improving or maintaining SOCc and improving nutrient flows, particularly in organic farming, while simultaneously providing renewable energy.

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