Seasonal changes in populations of sheep tick, Ixodes ricinus (L., 1758) (Acari: Ixodinae) in natural biotopes of St. Petersburg and Leningrad province, Russian Federation

2019 ◽  
Vol 24 (4) ◽  
pp. 701
Author(s):  
Luydmila Anatolyevna Grigoryeva ◽  
N.k. Tokarevich ◽  
O.A. Freilikhman ◽  
E.P. Samoylova ◽  
G.A. Lunina

Changes in the seasonal activity and age composition of adults and nymphs in populations of the Ixodes ricinus in northwestern Russia have been studied. Adult ticks and nymphs were collected on flag twice a month from April to October in 2014–2016. They were investigated for biological age (light-optical preparations of the midgut after staining fat with Sudan III). DNA isolated from ticks was analyzed using real-time PCR (fluorescent probe technology) for the presence of Borrelia burgdorferi s.l. pathogens based on amplification of the 16SrRNA and Hbb gene fragments.        The season of activity of the adults shows one peak, the largest numbers show up in July–August (September). The population of adults is composed of two generations. The first generation is active from the beginning of the season until nearly its end, mid-October. Until the end of June, young individuals with large fat reserves predominate in the population. From July to the end of September, the adult population is formed mainly of mature individuals. Older individuals in the population appear from mid-July, and become dominating only in August and, mainly, in September. Ticks of the second generation, as young individuals, were recorded from the end of August until the end of the season of activity. The active nymphs were captured from late April until late October. The season of activity of nymphs begins and ends with a 100% content of young individuals. The spring population (April–May) consists of young nymphs, in June the proportions of young and mature are equalized, in July and August the ratio of mature and old nymphs is balanced, in September old individuals prevail, which were not found in October. The first generation is the nymphs who have hatched from August to October during the previous season, and the second one is the nymphs hatching in August of the current year. The lifespan of adults and nymphs can reach 13–15 months. The proportion of infected ticks in May and June is 24.5% and 25%, with the highest rates of in the young (10–12 months) part of population (70–85% of individuals). In July, the number of mature (12–13 months) individuals increases (up to 75–95%), at the same time the average values of infection fall to 20.8%. In August, the shares of mature (45–55%) and old -13–15 months (45–55%) individuals are approximately balanced. Borrelia contamination is also decreasing (14.3%). In September, the number of mature individuals (29.7%) was about 2 times lower than the old ones (65.3%), and the infection rate decreased to 11.4%.        The population of nymphs and adults is composed of two tick generations in the season of activity. The season of activity of adult ticks is holistic; it is not interrupted during the summer months. Infection of adults with Borrelia decreases simultaneously with the ageing of the population.

2019 ◽  
Author(s):  
Zac Wylde ◽  
Foteini Spagopoulou ◽  
Amy K Hooper ◽  
Alexei A Maklakov ◽  
Russell Bonduriansky

Individuals within populations vary enormously in mortality risk and longevity, but the causes of this variation remain poorly understood. A potentially important and phylogenetically widespread source of such variation is maternal age at breeding, which typically has negative effects on offspring longevity. Here, we show that paternal age can affect offspring longevity as strongly as maternal age does, and that breeding age effects can interact over two generations in both matrilines and patrilines. We manipulated maternal and paternal ages at breeding over two generations in the neriid fly Telostylinus angusticollis. To determine whether breeding age effects can be modulated by the environment, we also manipulated larval diet and male competitive environment in the first generation. We found separate and interactive effects of parental and grandparental ages at breeding on descendants’ mortality rate and lifespan in both matrilines and patrilines. These breeding age effects were not modulated by grandparental larval diet quality or competitive environment. Our findings suggest that variation in maternal and paternal ages at breeding could contribute substantially to intra-population variation in mortality and longevity.


2020 ◽  
Vol 54 (s41) ◽  
pp. 89-115
Author(s):  
Einat Gonen

Abstract This paper presents a diachronic study of Modern Hebrew agreement between numerals and their quantified nouns. This research is possible thanks to the discovery of two rare collections of recordings from the 1950s and 1960s, which document four generations of speakers and have become important sources of spoken Early Modern Hebrew. On the basis of these two corpora, I compare numeral agreement in the first two generations of speakers with present-day usage and analyze trends of change and conversation in Modern Hebrew. The study shows that the first generation of speakers (“Gen1”) largely acquired the gender distinction of cardinals. However, in contrast to other agreement issues that educated Gen1 speakers realized fully, numeral use showed variation and absence of agreement in a small set of cases. Moreover, some linguistic features of Gen1 Hebrew found in this study no longer characterize Present-Day Hebrew; among these features is prosodic conditioning, which led to a Gen1 tendency to use the feminine form of the numeral ‘four’ with masculine nouns more frequently than was the case with other numerals.


1986 ◽  
Vol 118 (4) ◽  
pp. 351-359 ◽  
Author(s):  
M.T. AliNiazee

AbstractSeasonal history, adult flight activity, and damage of the obliquebanded leafroller, Choristoneura rosaceana (Harris), on filbert were studied during a 7-year period between 1976 and 1984. Data from periodic field counts and moth catches in sex-attractant traps indicated two generations per year. The first-generation adult capture peak was generally higher than the second, except in 1978 when about an equal number of moths were trapped from both generations. A physiological time scale, using degree-days (DD), was devised for predicting emergence of obliquebanded leafroller adults. The first adults from overwintering larvae emerged at approximately 374 DD above a threshold of 10 °C starting 1 March. A total of 1172 DD were required between the first and the last adult emergence during the first generation and about 519 DD during the second generation. The obliquebanded leafroller causes both foliar and nut damage in filbert orchards of Oregon. Foliar damage was insignificant, but nut damage, caused exclusively by the first-generation larvae during June and early July, was highly destructive. Larval feeding on nuts caused staining and premature drop of infested nuts resulting in substantial yield reduction in heavily infested orchards.


Author(s):  
A. V. Nozdracheva ◽  
T. A. Semenenko ◽  
S. G. Mardanly ◽  
S. V. Rotanov

Aim. Qualitative and quantitative evaluation of humoral immunity regarding causative agents of controllable infections in pregnant women in Moscow. Materials and methods. Sera of 559 pregnant and 201 non-pregnant women were studied for the presence of antibodies against measles and rubella virus by ELISA. Results. A significant proportion of individuals seronegative to measles was detected among pregnant (21.5%) and non-pregnant (29.1%) women aged 18 - 45, that exceeds the level acceptable by regulatory requirements by 3.1 and 4.2 times, respectively. The parameter increased with age and among seropositive individuals a high concentration of IgG against measles was noted. This gives evidence, that older individuals are not covered by measles vaccination enough, and a significant part of them has post-infection immunity that is higher and more robust compared with post-vaccination. Regarding rubella infection, a more favorable situation was established: proportion of seronegative individuals among the examined was 8.9 and 10.5%, respectively. The proportion of seronegative individuals decreased with age, and by age 36 - 45 reached the minimal 4,7%. A maximum amount of rubella seronegative individuals was detected in the 26-30 age group - 12.5%, as well as maximum proportion of individuals who have high concentration of specific IgG. An increase of the amount of seronegative results was observed with the increase of gestation period for both infections. Correlation between intensity of immunity against measles and rubella in the examined women was not present. Conclusion. Means for development of extra vaccination of the adult population and execution of laboratory examination of pregnant and women planning pregnancy are proposed regarding not only rubella, but also measles.


2013 ◽  
Vol 47 (1) ◽  
pp. 438 ◽  
Author(s):  
I. Thabet ◽  
A. Kilias ◽  
A. Koroneos ◽  
S. Kamh

The study deals with the petrography of the granitoid rocks intruding the five (A to E) domes of Hafafit Culmination. The morphological characteristics of zircon crystals are also examined, in order to elucidate the genesis of zircon and their host Hafafit granitoids. The granitoid rocks are tonalites, granodiorites and quartz diorites, all exhibiting gneissic texture. The zircon crystals from all the rock types intruding each one of the domes are examined in detail for colour, inclusions, crystal length, crystal width, elongation ratio, crystal form and habit, degree of roundness and corrosion, and are distinguished in groups on the basis of the previous characteristics. Two generations of zircons have been recognized; the first generation with magmatic features and the second one with post magmatic features. The first generation of zircon is attributed to the subduction, magmatic and deformation events while the second generation of zircon is attributed to metamorphism.


2021 ◽  
Vol 29 ◽  
pp. 41-46
Author(s):  
V. A. Katsan ◽  
A.I. Potopalsky ◽  
B.O. Zadorozhnii

Aim. The investigation of the influence of the constituents of Izatison, DMSO and PEG400, on the oat growth and its grain productivity during 2 generations after the seed treatment became the aim of this study for the elucidation of mechanism of Izatison stimulant influence. Methods. The broad scale of the concentrations of the solvents composition in the proportion, to be as in Izatison, was used. The plants were grown in the field. The growth processes were evaluated by the stem height on the tubing stage. The grain productivity was characterized by the panicle length, the grains number in the panicle and of theirs weight. Results. The dependence of influence of the solvents composition on the stem growth from its concentration was detected in the first generation. In some variants the negative influence was revealed on the grains number in the panicle and on theirs weight. The stimulation of the growth regardless from the solvents concentration was observed in the second generation and the more pronounced negative effect on the grain productivity. Conclusions. The solvents DMSO and PEG400 are able to influence on the oat growth and its productivity, and that effect was manifested also in 2 generation after the seed treatment. Keywords: Izatison, DMSO, PEG400, oat growth and grain productivity.


2017 ◽  
Vol 9 (4) ◽  
pp. 1994-2003
Author(s):  
Hemant Sharma ◽  
Maha Singh Jaglan ◽  
S. S. Yadav

Biology of pink stem borer, Sesamia inferens (Walker) (Lepidoptera: Noctuidae) was conducted during 2015-16 in laboratories of CCS Haryana Agricultural University, Regional Research Station, Karnal on HQPM 1 (hybrid) and HKI 1128 (inbred) for two generations at room temperature. Results on biology of S. inferens in the first generation revealed that incubation period varied from 10-14 days on HQPM 1 and 11-15 days on HKI 1128. The larval duration lasted for 21-37 days on HQPM 1 and 24-39 days on HKI 1128. The adult longevity of male and female ranged from 6-7 days and 7-8 days on HQPM 1 and 5-7 days and 6-7 days on HKI 1128, respectively. The total life span ranged from 63-72 days for female and 45-58 days for male on HQPM 1 and 65-74 days for female and 49-62 days for male on HKI 1128, respectively in the first generation. The total life span in second generation ranged 94-107 days for female and 83-96 days for male on HQPM 1 and 98-112 days for female and 86-101 days for male on HKI 1128. The biology of an insect pest is a condition precedent to find out its management strategies. The biology of S. inferens on maize has not yet been studied in north western part of the country. Having regards to the fact that no systematic work on this aspect has been carried out, studies were conducted on biology of this pest for developing efficient pest management strategies.


2012 ◽  
Vol 23 (2) ◽  
pp. 65-76
Author(s):  
Willi Goetschel

This paper examines Rosenzweig?s philosophic project in the context of his time as a critical intervention in the discussion of the place of Jewish thought in the university and in society. If Hermann Cohen represented the first generation of Jewish philosophers claiming that participation in the university is constitutive for the institution?s claim to universalism, the second generation-represented by Martin Buber - was more diffident about the university and its openness. For Buber, literary modernism offered what the university would refuse. Disappointed about the failure of the recognition of the efforts of the previous two generations, Rosenzweig represents the third generation. He turns the situation into a creative response anchoring philosophy as a project that calls for a resolute move outside the university.


2003 ◽  
Vol 131 (5-6) ◽  
pp. 244-248 ◽  
Author(s):  
Slobodan Nikolic ◽  
Jelena Micic ◽  
Slobodan Savic ◽  
Milan Gajic

INTRODUCTION Each fracture of long or pelvic bones as well as large contusions of subcutaneous fat tissue cause releasing of fat globules that rapidly penetrate into circulation through the ruptured veins of the injured tissue, and reach the lung circulation [1,2]. During the first phase, fat emboli block the functional lung circulation by their mechanical effect in capillaries producing so called isolated post-traumatic lung fat embolism [3]. The surface layer of a fat embolus, which is practically in liquid state, behaves as a membrane of very high density, i.e., as it is under high pressure which obstruct the blood stream [4] that is finally stopped at the level of lung blood vessels with diameter of approximately 20 ? [5].This pathophysiological mechanism produces cor pulmonale acutum, with poor pathological findings [8]. Nowadays, the post-mortem diagnosis of lung fat embolism is based on microscopical examination of tissue specimens, usually prepared with special histological staining (Sudan III) [9]. The grading of fat embolism according to Sevitt's criteria is generally accepted [10]. Taking of slices from apicoventral areas of the lungs has been recommended [11]. With longer outliving period, the total number of fat emboli in the lung circulation gradually decreases, due to their disintegration and resorption. It has been stated that fat globules completely disappear about 4-6 weeks after injury, and that they should not be searched for microscopically in this post-traumatic phase [11]. OBJECTIVES The aim of our work was to determine whether the age of injured, their gender, total severity of trauma, outliving period, and hypovole-mic shock that develops after injuring, may induce development of more severe forms of post-traumatic lung fat embolism. MATERIAL AND METHODS A prospective histological study was performed on the autopsy material of the Institute of Forensic Medicine in Belgrade. The analyzed sample consisted of individuals with injuries that might be a source of fat emboli (fractures of long bones, large contusions of subcutaneous fat tissue). The lung slices were systematically taken and stained with special fat staining (Sudan III). In each particular case, the grade of lung fat embolism was counted on the basis of microscopical appearance, according to Sevitt's criteria. The total severity of trauma was estimated by calculation of the Injury Severity Score (ISS) [13,14]. In no cases from the analyzed sample, the fat embolism was mentioned as either singular or plural cause of death. The obtained results were analyzed by means of appropriates statistical methods (ANOVA LSD-test, x2 test, Man-Whitney test, Fischer's test of correct probability). RESULTS AND DISCUSSION The analyzed sample included 58 fatally injured individuals, 39 males and 19 females. The average age was 54.10 years (SD=16.56), the average value of ISS was 34.69 (SD=5.88), and the average outliving period was 3.74 days (SD=5.88). However, all these data look differently when the analyzed sample has been stratified and analyzed according to the estimated grade of lung fat embolism. It was not showed that severity of lung fat embolism depends on sex of the injured (^2=0.842 p>0.05). The groups with the slightest and the most severe grade of lung fat embolism are statistically significantly different in relation to age of individuals (ANOVA, p=0.017). By means of LSD test, it has been showed that the group with the most severe grade of lung fat embolism (grade III) is statistically significantly different comparing to other two groups (with grade I and II) in relation to the age of injured (the values are p=0.16 and p=0.19 respectively, and the both groups are less than p=0.05). In the group with the most severe grade of lung fat embolism, the older individuals are statistically significantly represented comparing to othertwo groups. CONCLUSION The analysis of our sample showed that the most severe grade of post-traumatic lung fat embolism (microscopical grade III according to Sevitt's criteria) was determined in older individuals, more severely injured, and with shorter outliving period. The severity of fat embolism depends neither on sex of the injured, nor on development of post-traumatic hypovolemic shock. The obtained results related to the influence of hypovolemic shock on severity of fat embolism should be accepted with a caution. Namely, sometimes there is an intention to simplify a procedure of creating of autopsy conclusion about the cause of death, so that loss of blood is not mentioned at all, in spite of fact that it could have been a concurrent cause of death, while in other cases exsanguination is designated as a sole cause of death, forgetting the possibility that fat embolism could have really been the immediate cause of death.


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