Population Fluctuations Research Articles

Development of colistin resistance via heteroresistance modeling in Klebsiella pneumoniae: A diagnostic study

Purpose: Colistin heteroresistance mediates the failure of antibiotic treatments, is prone to lead to colistin resistance, and has been frequently reported in <i>Klebsiella pneumoniae</i>. This study investigated origins of the increase in colistin resistance following colistin exposure to colistin-heteroresistant <i>K. pneumoniae</i>.Methods: A modeled colistin-heteroresistant <i>K. pneumoniae</i> strain (i.e., mimicking colistin- heteroresistant [m-CL<sup>HR</sup>]) was generated using a susceptible <i>K. pneumoniae</i> strain ATCC 10031 and its resistance-induced mutant. Heteroresistance patterns were investigated through population analysis profiling (PAP), competition assays, and fluctuation and stability tests. An <i>in vitro</i> time-killing assay for colistin was performed for the m-CL<sup>HR</sup> to identify the change in susceptible and resistant populations before and after colistin exposure.Results: The generated m-CL<sup>HR</sup> strain showed a typical heteroresistance pattern for colistin in PAP, and its competition assay did not show fitness costs for any population. The ratio of resistant cells to susceptible cells did not deviate significantly from the range of heteroresistance in the fluctuation test, while the ratios of resistant cells preserved their stability. The <i>in vitro</i> time-killing assay thus showed that the resistant cells increased upon colistin exposure; sequencing analyses confirmed that the surviving resistant cells did not originate from susceptible cells by mutation. This study successfully modeled a colistin-heteroresistant <i>K. pneumoniae</i> strain, i.e., m-CL<sup>HR</sup>.Conclusion: In this modeled heteroresistant strain, only the colistin-resistant population survived the colistin treatment—this suggests that the development of colistin resistance from heteroresistant strain is because of the selection of a resistant population and not by the induction of resistance through mutations in susceptible populations.

Taking the beat of the Arctic: are lemming population cycles changing due to winter climate?

Reports of fading vole and lemming population cycles and persisting low populations in some parts of the Arctic have raised concerns about the spread of these fundamental changes to tundra food web dynamics. By compiling 24 unique time series of lemming population fluctuations across the circumpolar region, we show that virtually all populations displayed alternating periods of cyclic/non-cyclic fluctuations over the past four decades. Cyclic patterns were detected 55% of the time (n = 649 years pooled across sites) with a median periodicity of 3.7 years, and non-cyclic periods were not more frequent in recent years. Overall, there was an indication for a negative effect of warm spells occurring during the snow onset period of the preceding year on lemming abundance. However, winter duration or early winter climatic conditions did not differ on average between cyclic and non-cyclic periods. Analysis of the time series shows that there is presently no Arctic-wide collapse of lemming cycles, even though cycles have been sporadic at most sites during the last decades. Although non-stationary dynamics appears a common feature of lemming populations also in the past, continued warming in early winter may decrease the frequency of periodic irruptions with negative consequences for tundra ecosystems.

Circadian Variation of Immune Cell Populations in Preterm Human Milk: A Preliminary Study.

Introduction: Breast milk contains both nutritional and non-nutritional components for the newborn, with some of the latter exhibiting marked diurnal variations in concentration. This study aimed to analyze the circadian behavior of specific immune cell populations and proinflammatory cytokines present in the transitional milk of premature infants. Methods: The study quantified cellular components, including stem and immune cells, using flow cytometry. Additionally, ELISA assays were employed to measure proinflammatory cytokine concentrations. Results: Flow cytometry analyses revealed a diurnal rise in the percentage of CD23+, CD32+, CD36+, CD2+, and Tγδ cell populations. Conversely, nocturnal increases were observed in the percentage of CD16+, CD19+, and CD4+ populations. Notably, CD3+ and CD8+ populations did not exhibit any rhythmic variations. Proinflammatory cytokine concentrations were found to be higher in daytime milk samples compared to those collected at night. Conclusion: This study demonstrates rhythmic fluctuations in both immune cell populations and proinflammatory cytokine concentrations within the transitional milk of premature mothers.

The influence of climate oscillations and geological events on population differentiation of Camponotus japonicus in the Chinese mainland.

Camponotus japonicus (Hymenoptera: Formicidae) is an omnivorous social insect which builds sizable colonies in sparse woodlands or cropland and spreads across multiple climatic zones in the Chinese mainland. This study aims to reveal the role of climate changes and geological events in driving the genetic structure of social insect populations by investigating the phylogenetics and historical demography of C. japonicus in the Chinese mainland. Phylogenetic analyses were conducted based on the mitochondria DNA dataset using MrBayes and IQ-TREE. We constructed a haplotype network, calculated analyses of molecular variance, estimated the divergence time, and reconstructed the maximum clade credibility tree. Mismatch distribution and Bayesian skyline plots were used to infer historical population fluctuations. Additionally, ecological niche modeling was employed to predict the potential distribution of the species during the present, mid-holocene, and last glacial maximum periods in the Chinese mainland. The phylogenetic tree and median-joining network analyses support the presence of four distinct lineages in C. japonicus. These lineages exhibit significant genetic differentiation and limited gene flow. The divergence among the four lineages began in the early Pleistocene, approximately 1.41 million years ago (Ma). Subsequently, the central lineage diverged from both the northern and southern lineages around 1.16 Ma, while the northern and southern lineages diverged from each other at approximately 1.07 Ma. Population expansion was observed in the southern, central, and northern lineages prior to the last glacial maximum, while the Yunnan-Sichuan lineage experienced a slight increase in population size in more recent times. The predicted distribution of the species corresponds well with the actual distribution. Furthermore, the current suitable habitat areas in northern Xinjiang, southern Tibet, and the southeast coastal regions have significantly decreased compared to the last glacial maximum and the mid-holocene periods. Our results suggest that climate oscillations and geological events play an important role in driving genetic patterns and differentiation of C. japonicus. Mountain barriers isolate populations from each other, hinder the flow of genes, and effectively prevent the spread of this species. But at the same time, it also formed refugia at low altitudes areas such as Qinling-Bashan Mountains and Yanshan-Taihang Mountains and provide suitable habitats during glaciation. This study provides a good model for understanding how complex climate changes and geological events affect population genetic differentiation of social insects in the Chinese mainland.

Beneath the Surface: Investigating soil microbial and metazoa communities at various depths in a natural desert ecosystem inhabited by Karelinia caspia

Soil organisms play a pivotal role in terrestrial ecosystems, sparking growing curiosity about the comprehensive diversity of subterranean biota across large ecological levels. Soil inhabitants’ exhibit varied responses to soil physicochemical properties (SPPs) across desert ecosystem. Yet, the knowledge of their population dynamics across different soil depths (SDs) in the indigenous natural dominant zone of Karelinia caspia, a primary desert shrub in China, remains limited. This study employed advanced illumina sequencing to assess soil bacteria, fungi, archaea, protist, and metazoa populations across six distinct SDs (0 to 100 cm) within the K. caspia desert landscape. Our findings indicate a descending alpha diversity pattern in bacteria, archaea, and protists as soil depth increases, contrary to fungi and metazoa, which exhibit the opposite trend. SDs significantly shape soil biota beta diversity, notably impacting bacteria, protists, and fungi, as revealed by Non-Metric Dimensional Scaling. Prominent classes include Actinobacteria, Sordariomycetes, Nitrososphaeria, Spirotrichea, and Nematoda for soil bacteria, fungi, archaea, protists, and metazoa, respectively. Correlation analysis between predominant biotic communities' vertical distribution and SPPs variations revealed total potassium (TK) and pH's pronounced influence on bacteria, while fungi were affected by total nitrogen (TN) and soil water content (SWC). Archaea exhibit sensitivity to SWC, available potassium (AK), and available phosphorus (AP); protists respond to C/N-Ratio, nitrate (NO3), and total phosphorus (TP); metazoa correlate with SWC, pH, and NO3. Overall, these findings offer valuable insights regarding population fluctuations of soil biota within naturally established K. caspia across vertical soil strata within China's desert ecosystem.

Determination of Adult Population Fluctuation, Infection Rate of European Grapevine Moth [Lobesia botrana (Denis & Schiffermüller) (Lepidoptera: Tortricidae)] in the Vineyards of Hazro District (Diyarbakır)

Üzüm hem taze hem de kuru olarak insan beslenmesinde tüketilen önemli bir meyvedir. Bununla birlikte Türkiye ekonomisi için üzüm önemli bir ihraç ürünüdür. Bağlarda bitki koruma açısından birçok zararlı böcek ve hastalık etmeni bulunmaktadır. Bağ alanlarında çiçek ve salkımda beslenerek verim ve kaliteyi olumsuz etkileyen ana zararlı Salkım güvesi Lobesia botrana Denis & Schiffermüller (Lepidoptera: Tortricidae)’dir. Bu çalışma, mazruni üzüm çeşidinin yoğun olarak yetiştirildiği Diyarbakır ili Hazro ilçesinde bağlarında 2021-2022 yılları arasında her biri 10’ar dekar olan iki bağda eşeysel çekici tuzaklar kullanılarak yürütülmüştür. Bağlarda ana zararlı olan Salkım güvesi’nin erginlerinin doğaya ilk çıkış zamanı, ergin popülasyon değişimi, aktif olarak doğada bulunduğu süre, döl sayısı ile bağlardaki salkımların bulaşıklık oranının belirlenmesi amaçlanmıştır. Çalışma sonucunda L. botrana ergin eşeysel çekici tuzaklarda ilk olarak 18 Nisan tarihinde ve erginlerin son olarak ta 14 Kasım tarihinde tespit edilmiştir. L. botrana ergin uçuşlarının bağ alanlarında yaklaşık 8 ay süreyle doğada aktif oldukları saptanmıştır. Zararlının 2021 yılında Hürriyet mahallesinde toplam 296 ergin/tuzak sayılmış olup, en fazla haftalık popülasyon yoğunluğu 21 Ekim (21 ergin/tuzak), Yazgı mahallesinde ise toplam 1844 ergin/tuzak sayılmış olup, en fazla haftalık popülasyon yoğunluğu 8 Temmuz (198 ergin/tuzak) tarihinde tespit edilmiştir. 2022 yılında ise, Hürriyet mahallesinde toplam 663 ergin/tuzak sayılmış olup, en fazla haftalık popülasyon yoğunluğu 27 Haziran (80 ergin/tuzak), Yazgı mahallesinde ise toplam 2055 ergin/tuzak sayılmış olup, en fazla haftalık popülasyon yoğunluğu 20 Haziran (233 ergin/tuzak) tarihinde tespit edilmiştir. Popülasyon yoğunluğuna bağlı olarak zararlının bölgede hasattan önce 3, hasat sonrası ise 1 olmak üzere yılda 4 tepe noktasını oluşturduğu ve doğa şartlarında tahmini olarak 4 döl verebildiği belirlenmiştir. Hürriyet mahallesindeki bağda salkımların zararlı ile bulaşık oranının yıllara göre sırasıyla %5 ve %23, Yazgı mahallesindeki bağda ise salkımların zararlı ile bulaşık oranının yıllara göre sırasıyla %25 ve %45 oranında olduğu tespit edilmiştir.

Stabilizing effects of spatially heterogeneous disturbance via reduced spatial synchrony on a rocky shore community.

Understanding how synchronous species fluctuations affect community stability is a main research topic in ecology. Yet experimental studies evaluating how changes in disturbance regimes affect the synchrony and stability of populations and communities remain rare. We hypothesized that spatially heterogeneous disturbances of moderate intensity would promote metacommunity stability by decreasing the spatial synchrony of species fluctuations. To test this hypothesis, we exposed rocky shore communities of algae and invertebrates to homogeneous and gradient-like spatial patterns of disturbance at two levels of intensity for 4 years and used synchrony networks to characterize community responses to these disturbances. The gradient-like disturbance at low intensity enhanced spatial β diversity compared to the other treatments and produced the most heterogeneous and least synchronized network, which was also the most stable in terms of population and community fluctuations. In contrast, homogeneous disturbance destabilized the community, enhancing spatial synchronization. Intense disturbances always reduced spatial β diversity, indicating that strong perturbations could destabilize communities via biotic homogenization regardless of their spatial structure. Our findings corroborated theoretical predictions, emphasizing the importance of spatially heterogeneous disturbances in promoting stability by amplifying asynchronous spatial and temporal fluctuations in population and community abundance. In contrast to other networks, synchrony networks are vulnerable to the removal of most peripheral nodes, which are less synchronized, but may contribute more to stability than other nodes by dampening large fluctuations in species abundance. Our findings suggest that climate change and direct anthropogenic disturbance can compromise the stability of ecological communities through combined effects on diversity and synchrony, as well as further affecting ecosystems through habitat loss.

Illustrating the current geographic distribution of Diaphorina citri (Hemiptera: Psyllidae) in Campeche, Mexico: a maximum entropy modeling approach

Abstract Diaphorina citri Kuwayama (Asian citrus psyllid) is a quarantine pest found in at least 60 countries, causing indirect damage as a primary vector of pathogens associated with Huanglongbing in citrus trees. Huanglongbing-infected trees die within 3–8 years, accompanied by economic losses in citriculture. D. citri has spread in Mexico to several states and is a high risk to Mexican citriculture due to its ability to cause damage and the lack of a disease cure. The primary objective of this research was to enhance our understanding of the current status of D. citri in southeastern Mexico. This study analyzed the distribution of D. citri in Campeche, Mexico from 2013 to 2020. The study generated 572,619 D. citri records from 40,620 yellow sticky traps deployed in 10 of the 12 municipalities of the state. We employed advanced MaxEnt and DivaGIS software to accomplish this study. Results showed population fluctuations with a peak during June and July from 2013 to 2019 and July and September in 2020. The study found a higher presence of D. citri in Campeche, Tenabo, Carmen, Champotón, and Escárcega and a higher incidence in Citrus latifolia Tanaka ex Q. Jiménez and Citrus sinensis (L.) Osbeck crops. The variance in the number of D. citri adults captured per year and the dispersion index (a parameter measuring the ability of insects to leave one ecosystem and move to another in search of suitable conditions for their survival and reproduction) was greater than the annual mean, demonstrating a spatially distributed, right-skewed aggregate. The elliptical polygon or standard deviation ellipse indicated the tendency for a less elongated ellipse in 2013–2014. From 2015 to 2018 D. citri expanded north towards Hecelchakán and south towards Champotón, Escárcega, and Carmen. In 2019, D. citri expanded north towards Champotón, Campeche, Tenabo, Hecelchakán, and Calkiní. The months with the most activity between 2013 and 2020 were May, June, July, and August, with June having the highest numbers collected. The results of the enveloped tests (parameter measuring how environmental conditions influence the spatial patterns of insect populations) showed the adaptability of D. citri to different conditions. D. citri prefers temperatures of 24.6–27.9 °C and 1,050–1,500 mm of rainfall. Areas with high-risk for D. citri are coastal and northern parts of the study area. Central Campeche is suitable, and southern parts have low to medium risk. Our research shows the relationship between climatic factors and the distribution of D. citri in the state of Campeche, Mexico. Moreover, our findings will be crucial for implementing effective surveillance measures in areas where the probability model indicates the potential presence of D. citri. This is especially significant due to the remarkable adaptability of D. citri to diverse environmental conditions.

Sporadic diurnal fluctuations of cyanobacterial populations in oligotrophic temperate systems can prevent accurate characterization of change and risk in aquatic systems

Cyanobacteria increasingly threaten recreational water use and drinking water resources globally. They require dynamic monitoring to account for variability in their distribution arising from diel cycles associated with oscillatory vertical migration. While this has been discussed in marine and eutrophic freshwater contexts, reports of diurnal vertical migration of cyanobacteria in oligotrophic freshwater lakes are scant. Typical monitoring protocols do not reflect these dynamics and frequently focus only on surface water sampling approaches, and either ignore sampling time or recommend large midday timeframes (e.g., 10AM-3PM), thereby preventing accurate characterization of cyanobacterial community dynamics. To evaluate the impact of diurnal migrations and water column stratification on cyanobacterial abundance and composition, communities were characterized in a shallow well-mixed lake interconnected to a thermally stratified lake in the Turkey Lakes Watershed (Ontario, Canada) using amplicon sequencing of the 16S rRNA gene across a multi-time point sampling series in 2018 and 2022. This work showed that cyanobacteria are present in oligotrophic lakes and their community structure varies (i) diurnally, (ii) across the depth of the water column, (iii) interannually within the same lake and (iv) between different lakes that are closely interconnected within the same watershed. It underscored the need for integrating multi-timepoint, multi-depth discrete sampling guidance into lake and reservoir monitoring programs to describe cyanobacteria community dynamics and signal change to inform risk management associated with the potential for cyanotoxin production. Ignoring variability in cyanobacterial community dynamics (such as that reported herein) and reducing sample numbers can lead to a false sense of security and missed opportunities to identify and mitigate changes in trophic status and associated risks such as toxin or taste and odor production, especially in sensitive, oligotrophic systems.

Balancing: A solution to our distorted indices of transient dynamics

AbstractBecause populations are at the mercy of random disturbances large and small, they rarely, if ever, converge on predicted long‐term behaviors. Therefore, when employing matrix population models, ecologists study the dynamics of populations that depart from stable distributions. Necessary for such studies are indices of transient dynamics that measure the size of short‐term population fluctuations. These indices advance our understanding of population dynamics by revealing that population growth rate in a single timestep can far exceed the stable population growth rate. Despite their value, indices of transient behavior possess two major shortcomings: they are scale dependent and easily distorted by outsized population classes. Distortion occurs whenever immature classes, due to their sheer size, carry greater weight in the calculation of population size than mature classes. Beluga sturgeon (Huso huso), for example, have an immature age class (eggs) that is several orders of magnitude larger than its mature age classes. To remove the undue influence of outsized classes, I use balancing, which rescales classes by the stable population distribution and makes the indices of transient dynamics scale invariant. I apply balancing to 1800 population projection matrices for various species across the Animal Kingdom, using reactivity and the Henrici metric of non‐normality as indices of transient dynamics. I found that balancing profoundly changes the picture of which populations have the greatest or least potential transient dynamics. Using a population projection matrix for northern pike (Esox lucius), I demonstrate how balancing influences pseudospectra contour plots that are used to infer transient dynamics.

Predicting potential distribution of the Rhinoncus sibiricus under climatic in China using MaxEnt.

In recent years, buckwheat (Fagopyrum spp.) is being increasingly damaged by the Siberian tortoise beetle (Rhinoncus sibiricus Faust). Adults and nymphs feed on leaf tissues and caulicles, thus damaging its stems and leaves. In this study, we investigated the habits, distribution, and environmental impact of R. sibiricus using MaxEnt, an ecological niche model. Geographic information about the infestation site from previous field surveys and climatic data from 2013 to 2018 were organized and optimized using R. The impact factors were calculated using MaxEnt software. The results indicate that population fluctuations in R. sibiricus are related to changes in temperature, humidity, and their spatial distribution. Under current climatic conditions, R. sibiricus is mainly distributed in northern China, with sporadic distribution in south-western China. The values for a survival probability threshold > 0.3 were: precipitation during the wettest month (bio13), 70.31-137.56 mm; mean temperature of the coldest quarter (bio11), -15.00-0.85°C; mean temperature of the warmest quarter (bio10), 11.88-23.16°C; precipitation during the coldest quarter (biol9), 0-24.39 mm. The main factors contributing > 70% to the models were precipitation during the wettest month and coldest quarter, and mean temperature during the warmest and coldest quarters. Under both future climate models, the center of the fitness zone moves northward. Our results will be useful in guiding administrative decisions and support farmers interested in establishing control and management strategies for R. sibiricus. This study could also serve as a reference for future research on other invasive pests.

Crustal thickness variation of the Dabie orogenic belt: Insights from detrital zircon evidence and geological significance

The Dabie orogenic belt is characterized by widely distributed Mesozoic ultrahigh-pressure metamorphic rocks. Together with the Qinling orogenic belt, it constitutes one of the most important collisional orogens in eastern Asia. Because of intense continental subduction and collision during the Mesozoic and subsequent denudation, it remains controversial whether pre-Mesozoic convergent events happened in the region of the Dabie orogenic belt. In this study, we reconstruct the crustal thickness variation of the Dabie orogenic belt based on detrital zircon data. Results reveal three stages of crustal thickening at ca. 900-800 Ma, ca. 530-400 Ma, and ca. 250-210 Ma that are likely associated with three major convergent events that happened between the North and South China Blocks since the Neoproterozoic. The first thickening stage is possibly related to long-term subduction-accretion-collision processes along the northern margin of the South China Block. The second one corresponds to early Paleozoic ocean closure and the arc-continent collision that happened between the North and South China Blocks. The third one is a most significant thickening that represents the final collision between the North and South China Blocks during the Mesozoic. The turning point (ca. 210 Ma) of the crustal thickness curve represents the cessation of ultradeep subduction and constrains the completion of Mesozoic continental collision. Late Archean crustal thinning may be related to the onset of plate tectonics. Overall, the fluctuations of crustal thickness and detrital zircon age populations from sediments of the Dabie orogenic belt suggest interaction among Chinese continental blocks is consistent with the evolution of global supercontinent cycles.

Survival of Listeria monocytogenes on Frozen Vegetables during Long-term Storage at −18 and −10°C

Two recent listeriosis outbreaks have occurred in the United States and Europe due to contaminated individually quick-frozen (IQF) vegetables. While one of the outbreaks was due to frozen vegetables considered ready-to-eat (RTE), the other was linked to frozen corn whose packaging contained cooking instructions and was considered not-ready-to-eat (NRTE). However, consumers may thaw certain frozen vegetables and consume without cooking. Since no data is available on the survivability of L. monocytogenes on IQF vegetables during frozen storage, this study examined the population of six different strains (comprising lineages 1/2a, 1/2b, and 4b) on IQF vegetables during long-term storage. Individual strains were inoculated onto an IQF vegetable mix at 4 log CFU/g and stored at −18 or −10°C for 360 days. Although fluctuations in populations of all strains were observed on the vegetables during storage, no significant differences based on strain, lineages, or temperature were observed. Overall, L. monocytogenes populations were only reduced by up to 0.47 and 0.59 log CFU/g after 360 days at −18 and −10°C, respectively. Results from this study suggest that L. monocytogenes is able to persist on IQF vegetables for extended time periods with no significant reduction in population. Future studies could evaluate the survival and growth of L. monocytogenes on IQF vegetables during thawing and storage.

Recent increasing homogenisation in Austrian butterfly communities over the past decades

In Europe, abundance, biomass and species richness of many insect taxa declined during the last decades. This decline might be accompanied by long‐term temporal changes in community composition and dominance orders. Here, we use the data base of the natural history museum of Salzburg based on museum records and field books on Austrian butterflies covering the years 1945–2018 and asked 1) whether and how community composition of important butterfly guilds changed and 2) whether these changes are in accordance with reciprocal shifts in species abundances leading to increased functional stability. In comparisons of annual changes in dominance orders, we found an increasing tendency of compositional stability of dominant species. The trend was most pronounced in generalist and dispersive species, while dominant grassland, xerothermophilic and sedentary species tended to decrease in relative abundance. We also demonstrate a temporal trend towards increasing regional stability in relative abundance rank orders. We did not find compelling evidence for reciprocal shifts in abundances of dominant and subdominant species of the same guild and of asynchronous population fluctuations as required by models that link abundance compensation and functional stability. Our study highlights the ongoing trend towards faunal homogenisation at regional spatial scales in the European Alps.

On the duration of face-to-face contacts

The analysis of social networks, in particular those describing face-to-face interactions between individuals, is complex due to the intertwining of the topological and temporal aspects. We revisit here both, using public data recorded by the sociopatterns wearable sensors in some very different sociological environments, putting particular emphasis on the contact duration timelines. As well known, the distribution of the contact duration for all the interactions within a group is broad, with tails that resemble each other, but not precisely, in different contexts. By separating each interacting pair, we find that the fluctuations of the contact duration around the mean-interaction time follow however a very similar pattern. This common robust behavior is observed on 7 different datasets. It suggests that, although the set of persons we interact with and the mean-time spent together, depend strongly on the environment, our tendency to allocate more or less time than usual with a given individual is invariant, i.e. governed by some rules that lie outside the social context. Additional data reveal the same fluctuations in a baboon population. This new metric, which we call the relation “contrast”, can be used to build and test agent-based models, or as an input for describing long duration contacts in epidemiological studies.

Population Dynamic of Fruit Fly Pests Bactrocera spp. in Salacca Orchard in Relation to Host Plants and Climate Factors

Fruit flies are an economic important of pest on horticultural crops. One of the commodities that are affected much due to fruit fly attack is salacca var. pondoh. The number of fruit flies attacking salacca increased from 2018 to 2021. The aims of the research was to study the population dynamics in salacca orchards in relation to climate factors and host plants. The research was conducted from July 2022 to May 2023 in salacca orchards that are members of the Salacca Farmers Association Mitra Turindo in Wonokerto, Turi, Sleman, Yogyakarta, Indonesia. The methods were counting the number of fruit flies trapped in three observation groups with different levels of sanitation and host plants around salacca orchards. Descriptive and arithmetic methods were used to determine the pattern of population oscillation among the three observation groups and differences in sanitation levels and host plants around the salacca orchards. The result showed that population fluctuations of <em>Bactrocera</em> spp. in salacca orchards were correlated with rainfall and relative humidity and less correlated with temperature and wind speed. Fruit fly abundance was lower in salacca orchards with better sanitation and fewer host plants around the salacca orchard.

The role of job crafting as an employee strategy in responding to organizational change and job satisfaction in health units in Greece: Cross sectional study

Background: In recent decades, in the context of organizational change, Job crafting is the process in which the redesign of work takes place, employees change their labor boundaries and labor relations to find meaning in them. Material and Method: Data were collected from 112 health care workers from the public and private sector regardless of specialty with a random sampling method. The data was collected by a questionnaire that included three parts: demographics, scale of organizational commitment, job satisfaction. The data was analyzed with SPSS version 24.0 using descriptive statistics, Pearson correlation, variance analysis and t-test. Purpose: To investigate job crafting as a strategy of employees in Health Units in Greece regarding organizational change and the factors that affect job satisfaction. Results: A statistically significant positive correlation was identified between the RCT scale and the MSQ satisfaction scale (r=0.299, p=0.002<a=0.05). The hypothesis of homogeneity of variations is not rejected for the Job crafting and RCT scales by Levene's test (p-values>a=0.05), while it is rejected for the MSQ scale (F=3.757, p-value=0.027<a=0.05). Subsequently, there was no statistically significant relationship between the Job Crafting scales, RCT of the questionnaire and age group (p-values>a=0.05) with application of One Way ANOVA. There was also no statistically significant difference (χ2(3)=2.068, p-value=0.558>a=0.05) so there is no differentiation in the degree of agreement of the MSQ scale per educational level. Finally, the hypothesis of equality of population fluctuations is not rejected (Vene test, F=2,507, p=0,116) and a statistically significant relationship between the Job Crafting scale in relation to the employment agency (t=-2,607, p=0,01) emerged. Conclusions: Job crafting has a positive impact on organizational change and job satisfaction is positively linked to the implementation of Job crafting. Planning and managing organizational change is a complex and difficult task for organizational managers. Reactions to organizational change can be multiple, often ambiguous and complex. Employees can respond to change in unexpected ways. They don't just face change, but they may also be actively involved with it and play an active role in influencing its direction. On the one hand, organizations and, on the other hand, managers should turn to work redesign interventions, leave room for employees to change their work routine and provide them with opportunities to "match" their work to their strengths, skills and preferences.

Deer in the extreme north-east of Russia: Koryak ecotype (Rangifer Tarandus L.)

Purpose: the study of economic and significant indicators of the Koryak ecotype of the northern deer.Materials and methods. The model for the study of the Koryak ecotype was the livestock of animals in agricultural enterprises for breeding the northern deer in the Kamchatka Peninsula during the stable development of the industry, with a total number of more than 125 thousand individuals. The entire number of deer was contained in 86 herds, on average in one herd, up to 1,400-1500 animals fell. Zootechnical information was taken from annual reports of deer farms. In the study of farms, indicators used in the reindeer husbandry industry were taken: the number of deer at the beginning of the year; the uterus in the structure of the herd (the number of important and heels in % to the total number of deer); offspring - received living calves at the end of the hotel per 100 uterus, %; DWT - a business exit of calves at the end of the year per 100 uterus, %; SVP - the safety of the adult number of deer at the end of the year, %; Production of meat in live weight, taking into account growth per 100 January deer, in C; Live weight of sexual age groups, kg.Results. The reindeer husbandry of the territory was distinguished by high quality indicators. The specific gravity of the uterus in the structure of the herd was maintained at 60 % and higher. The deer of this ecotype has good reproductive properties, on average at the end of the hotel there were more than 86 calves per 100 queens. The business yield of young animals at the end of the year on average ecotip was 80.6 % with fluctuations from 73 to 86.5 %, which confirms the high reproductive properties and viability of the young deer group of the northern deer. The safety indicator of the adult livestock at the end of the year was at the level of 93.9 % with fluctuations in individual populations from 90.4 % to 96.5 %. The production of meat in live weight, taking into account the growth of 100 deer according to individual scope, was flukes from 28 to 31.5 c, with an average ecotype value over 29.2 c. In terms of live weight of the Koryak ecotype deer, they exceeded the analogues of the sexual age groups of deer in the Chukotsk AO by 1.0-7.7 %, which confirms their high household chores. When crossing the deer of the Koryak ecotype and the Chukotka breed, a manifestation of heterosis was noted, since the estates significantly exceeded both initial parental forms in live weight, the preservation of the livestock, the business exit of young animals increased, and the production of meat increased. The identification of highly productive ecotypes and the creation on their basis of in -breed structures will increase the productivity of the northern deer.

Comparison of three indirect methods for density estimation of the wild boar (Sus scrofa) in different habitats in South Korea

Increasing human-wild boar conflicts in South Korea have led to a demand for effective management strategies. Absolute abundance, rather than relative indices, is needed for the long-term monitoring and population control of wild boars. Indirect methods for density estimation have become increasingly popular because they are cost-effective and do not have the risk of capture probability bias. We compared three indirect methods, including the non-invasive capture-recapture model (NICRM), random encounter model (REM), and fecal standing crop (FSC), in two different sites characterized by specific habitats (urban and agricultural environments). NICRM and REM reflected population fluctuation and hunting intensity assumptions at both sites; however, FSC did not reflect the latter. While using NICRM, efforts are needed for achieving a low genotyping error rate; this model would achieve more reliable results in low-density areas. REM with accurate parameter information (i.e., daily range, detection zone, and camera placement) could be the most effective density estimation method for long-term monitoring in South Korean environments. Conversely, FSC may not be recommended because of many factors, such as decomposition rate, rainfall, biased distribution of feces that might affect pellet groups. Additionally, the density estimates from this study can provide information for developing effective management strategies in South Korean environments.

Resource limitation and population fluctuation drive spatiotemporal order in microbial communities.

Microbial communities display complex spatiotemporal behaviors leading to spatially-structured and ordered organization driven by species interactions and environmental factors. Resource availability plays a pivotal role in shaping the dynamics of bacterial colonies. In this study, we delve into the intricate interplay between resource limitation and the emergent properties of a growing colony of two visually distinct bacterial strains having similar growth and mechanical properties. Employing an agent-based modeling and computer simulations, we analyze the resource-driven effect on segregation and sectoring, cell length regulation and nematic ordering within a growing colony. We introduce a dimensionless parameter referred to as the active layer thickness, derived from nutrient diffusion equations, indicating effective population participation due to local resource availability. Our results reveal that lower values of active layer thickness arising from decreased resource abundance lead to rougher colony fronts, fostering heightened population fluctuations within the colony and faster spatial genetic diversity loss. Our temporal analyses unveil the dynamics of mean cell length and fluctuations, showcasing how initial disturbances evolve as colonies are exposed to nutrients and subsequently settle. Furthermore, examining microscopic details, we find that lower resource levels yield diverse cell lengths and enhanced nematic ordering, driven by the increased prevalence of longer rod-shaped cells. Our investigation sheds light on the multifaceted relationship between resource constraints and bacterial colony dynamics, revealing insights into their spatiotemporal organization.