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The role of sociality in the demography of animals has become an intense focus of research in recent decades. However, efforts to understand the sociality–demography nexus have hitherto focused on single species or isolated taxonomic groups. Consequently, we lack generality regarding how sociality associates with demographic traits within the Animal Kingdom. Here, I propose a continuum of sociality, from solitary to tightly social, and test whether this continuum correlates with the key demographic properties of 152 species, from jellyfish to humans. After correction for body mass and phylogenetic relationships, I show that the sociality continuum is associated with key life history traits: more social species live longer, postpone maturity, have longer generation time and greater probability of achieving reproduction than solitary, gregarious, communal or colonial species. Contrary to the social buffering hypothesis, sociality does not result in more buffered populations. While more social species have a lower ability to benefit from disturbances, they display greater resistance than more solitary species. Finally, I also show that sociality does not shape reproductive or actuarial senescence rates. This cross-taxonomic examination of sociality across the demography of 13 taxonomic classes highlights key ways in which individual interactions shape most aspects of animal demography. This article is part of the discussion meeting issue 'Understanding age and society using natural populations'. [ABSTRACT FROM AUTHOR]

The life history traits of the invasive slug, Deroceras laeve, occurring in the Darjeeling Himalayas, India, were estimated under laboratory conditions using the hatchlings from eggs of field-collected D. laeve. The growth pattern of D. laeve was found to be logarithmic, rapidly increased initially, and reached a stable condition till death. The maximum life span of D. laeve was 138 ± 3.48 days, with slightly higher mortality during the juvenile period, which decreased gradually at older ages. The pre-reproductive period of 37 ± 2.7 days, reproductive period of 100.8 ± 5.2 days, and 5.4 ± 1.72 days post-reproductive period of D. laeve were observed. D. laeve attained sexual maturity during 38 ± 2.7 days, and the age-specific fecundity increased with increasing age. The hatchability of the eggs was observed to be > 75% following the incubation period of 14.25 ± 0.49 days. The net reproductive value (R0), generation time (Tc), and finite rate of increase (λ) were 40.01, 12.48 weeks, and 1.455, respectively. Apparently, the earlier sexual maturity, high net reproductive rate, and shorter generation time of D. laeve are indicative of its invasive nature as well as prospective range expansion in similar geographic locations. [ABSTRACT FROM AUTHOR]

Background: The slow breeding cycle presents a significant challenge in legume research and breeding. While current speed breeding (SB) methods promise faster plant turnover, they encounter space limitations and high costs. Enclosed environments risk pest and disease outbreaks, and supplying water and electricity remains challenging in many developing nations. Here, we propose an innovative natural speed breeding (nSB) approach to achieve two generation cycles per rabi season under natural open field conditions in chickpea. This cost-effective, environmentally friendly method offers a location-specific alternative to prevalent SB techniques. Results: Two field experiments were conducted. First, 11-day-old fresh immature green (FIG) seeds exhibited an 80% germination rate, reducing the duration of the breeding cycle by 14%. In second, abiotic stresses such as atmospheric, nutrient, soil, and water stresses reduced the duration of the breeding cycle by 40%, 18%, 15%, and 18%, respectively. Despite the shortened generation time, we consistently obtained a minimum of 4–6 pods plant-1, ensuring continuity in the subsequent breeding cycle without compromising the nSB process. Conclusion: Our investigation revealed that the combination of this location advantage (40%) with the sowing of FIG seeds (14%) enables Baramati to achieve progress from F2 to F5 in 1.5 years, with two generation cycles per rabi (cool) season. Using the nSB method can save 3 years, marking a notable reduction from the conventional six-year timeline. Moreover, incorporating the additional abiotic stresses mentioned above will further reduce the generation advancement time. Therefore, nSB accelerates generation turnover and reduces varietal improvement time at a low cost. [ABSTRACT FROM AUTHOR]

Abstract Background The slow breeding cycle presents a significant challenge in legume research and breeding. While current speed breeding (SB) methods promise faster plant turnover, they encounter space limitations and high costs. Enclosed environments risk pest and disease outbreaks, and supplying water and electricity remains challenging in many developing nations. Here, we propose an innovative natural speed breeding (nSB) approach to achieve two generation cycles per rabi season under natural open field conditions in chickpea. This cost-effective, environmentally friendly method offers a location-specific alternative to prevalent SB techniques. Results Two field experiments were conducted. First, 11-day-old fresh immature green (FIG) seeds exhibited an 80% germination rate, reducing the duration of the breeding cycle by 14%. In second, abiotic stresses such as atmospheric, nutrient, soil, and water stresses reduced the duration of the breeding cycle by 40%, 18%, 15%, and 18%, respectively. Despite the shortened generation time, we consistently obtained a minimum of 4–6 pods plant-1, ensuring continuity in the subsequent breeding cycle without compromising the nSB process. Conclusion Our investigation revealed that the combination of this location advantage (40%) with the sowing of FIG seeds (14%) enables Baramati to achieve progress from F2 to F5 in 1.5 years, with two generation cycles per rabi (cool) season. Using the nSB method can save 3 years, marking a notable reduction from the conventional six-year timeline. Moreover, incorporating the additional abiotic stresses mentioned above will further reduce the generation advancement time. Therefore, nSB accelerates generation turnover and reduces varietal improvement time at a low cost.

This study was aimed to investigate the physicochemical structure of fresh and dried Aloe Vera gel (AVG) and its adequacy as a prebiotic in the preparation of Synbiotic fermented milk with Bif. Lactis BB-12, in addition to its effect on the survival of these bacteria during 28 days of cold storage. The results indicated that the yield of the gel was % 64.56±1.157, and the moisture content, total solids (TS) and total soluble solids (TSS) in the fresh gel were % 98.23±0.0816, %1.777±0.0103 and % 1.56±0.0816 respectively. The pH of fresh and dried gel was 4.48±0.0105 and 4.63±0.01, respectively, meanwhile the acidity was 0.083±0.00121 and 0.058±0.0083, respectively (expressed as malic acid). Addition of 0.03%, 0.05% of dried and 3%,5% of fresh AVG to treatments under study which represented as B1, B2, B3, and B4 respectively, reduced the generation time (GT) to 71.91, 68.49, 80.14 and 95.17 min, respectively as compared to that of the control treatment B0 (AVG free), which was 112.52 min. The pH value decreased in treatments B0, B1, B2, B3, and B4 to 4.45, 4.41, 4.36, 4.39 and 4.38, respectively, as the acidity increased to 1.13, 1.18, 1.26, 1.20 and 1.21%, respectively. [ABSTRACT FROM AUTHOR]

Considering fast-changing environment, emerging pathogens, and the imminent need to feed a global population that is predicted to increase to 9–10 billion people by the year 2050, plant breeders are faced with the challenge of exploring more efficient crop improvement strategies. The urgency to enhance crops under these conditions has become a paramount concern for scientists worldwide, as current crop enhancement projects progress at a pace insufficient to meet the growing food demand. Traditional breeding methods, which often take over 10 years to develop high-performing cultivars with desired traits, are proving to be inadequate. However, a new approach known as Speed breeding presents a game-changing opportunity for crop improvement in the face of a changing world offering the potential to significantly accelerate the development, marketing, and commercialization of improved plant varieties. Speed breeding, a methodology that manipulates temperature, light duration, and intensity to accelerate plant development, has emerged as a promising solution for achieving climate resilience, long-term yield, and nutritional security. Recent innovations in breeding technologies, including genotyping, marker-assisted selection (MAS), high throughput phenotyping, genomic selection (GS), overexpression/knock-down transgenic techniques, and genome editing, can be combined with speed breeding to achieve more precise and expedited outcomes in crop enhancement. This review explores the key opportunities and challenges associated with speed breeding to guide pre-breeding and breeding programs. To achieve more efficient outcomes in enhancing major food crops, this review highlights various alternative approaches and strategies adopted for speed breeding. Integrating speed breeding with existing technologies will be essential for future crop breeding success, and concerted efforts and ongoing research holds the potential to pave the way for a resilient and productive agricultural future. [ABSTRACT FROM AUTHOR]

By quantifying key life history parameters in populations, such as growth rate, longevity, and generation time, researchers and administrators can obtain valuable insights into its dynamics. Although point estimates of demographic parameters have been available since the inception of demography as a scientific discipline, the construction of confidence intervals has typically relied on approximations through series expansions or computationally intensive techniques. This study introduces the first mathematical expression for calculating confidence intervals for the aforementioned life history traits when individuals are unidentifiable and data are presented as a life table. The key finding is the accurate estimation of the confidence interval for r , the instantaneous growth rate, which is tested using Monte Carlo simulations with four arbitrary discrete distributions. In comparison to the bootstrap method, the proposed interval construction method proves more efficient, particularly for experiments with a total offspring size below 400. We discuss handling cases where data are organized in extended life tables or as a matrix of vital rates. We have developed and provided accompanying code to facilitate these computations. • Analytical confidence intervals for life history parameters in demography. • The most relevant finding is the expression for the CI for the growth rate. • The method is more efficient than bootstrap, especially if sample size is small. [ABSTRACT FROM AUTHOR]

Cicadas have amongst the longest development times and are also amongst the largest insects. Cicadas feed exclusively on xylem fluid, which is nutritionally dilute and difficult to obtain. One possible explanation for their slow development is that poor nutrition limits their growth rate. An analysis of 30 cicada species with known development times is consistent with this hypothesis as species with more equatorial distributions grew more rapidly than those at higher latitudes. A second possible explanation is that prolonged development maximizes net reproductive rate because there is little risk of mortality once early instar cicada nymphs establish feeding sites. Extended development probably allows nymphs to store resources and produce more offspring. Spittlebugs also feed obligately on xylem fluid and grow at similarly slow rates although they attain small adult sizes. Unlike cicadas, spittlebugs do not have steep survivorship curves and have shorter development times. The life histories of cicadas and spittlebugs are therefore consistent with both hypotheses. Cicada development times may be limited if (1) the risk of nymphal mortality equals increased fecundity associated with prolonging development, (2) fluctuating conditions sometimes favour rapid development times, or (3) host plant quality changes over time and penalizes nymphs that cannot relocate feeding sites.

Background: This study identified the risk factors for severe acute respiratory syndrome coronavirus 2 infection among household contacts of index patients and determined the incubation period (IP), serial interval, and estimates of secondary infection rate in Kerala, India. Methods: We conducted a cohort study in three districts of Kerala among the inhabitants of households of reverse transcriptase polymerase chain reaction‐positive coronavirus disease 2019 patients between January and July 2021. About 147 index patients and 362 household contacts were followed up for 28 days to determine reverse transcriptase polymerase chain reaction positivity and the presence of total antibodies against SARS‐CoV‐2 on days 1, 7, 14, and 28. Results: The mean IP, serial interval, and generation time were 1.6, 3, and 3.9 days, respectively. The secondary infection rate at 14 days was 43.0%. According to multivariable regression analysis persons who worked outside the home were protected (adjusted odds ratio [aOR], 0.45; 95% confidence interval [CI], 0.24–0.85), whereas those who had kissed the coronavirus disease 2019‐positive patients during illness were more than twice at risk of infection (aOR, 2.23; 95% CI, 1.01–5.2) than those who had not kissed the patients. Sharing a toilet with the index patient increased the risk by more than twice (aOR, 2.5; 95% CI, 1.42–4.64) than not sharing a toilet. However, the contacts who reported using masks (aOR, 2.5; 95% CI, 1.4–4.4) were at a higher risk of infection in household settings. Conclusions: Household settings have a high secondary infection rate and the changing transmissibility dynamics such as IP, serial interval should be considered in the prevention and control of SARS‐CoV‐2. [ABSTRACT FROM AUTHOR]

The IUCN Red List of Threatened Species is an authoritative tool in biodiversity conservation. Whilst IUCN criteria have been applied successfully to groups such as birds and mammals, a Red List assessment of British seaweeds in 2021 revealed that the categories to which seaweed species were assigned were dependent on how the criteria were applied. Here, this seaweed assessment is used as a case study with which to evaluate the IUCN methodology for use with 'non-standard' groups of organisms. A data-driven assessment of red (Rhodophyta), green (Chlorophyta) and brown (Phaeophyceae) seaweeds, which applied three (A, B and D) of the five IUCN criteria (A–E), categorized 13% of 617 British species as threatened. Following peer review, only 7% of species were categorized as threatened (1% Critically Endangered—CR, 3% Endangered—EN, 3% Vulnerable—VU), and 55% as Data Deficient. This reduction in species categorized as threatened suggests that strict application of the IUCN criteria may, at least for the seaweeds, over-estimate threat. As a result of this assessment, recommendations include the need for a more unified monitoring system and a review of the suitability for/application of the IUCN assessment criteria to some types of organisms. For example, in clonal populations, it is not possible to count individuals, and complex life histories cause additional complications. IUCN criteria must be applicable to a wide range of organisms, including seaweeds. [ABSTRACT FROM AUTHOR]

Abstract Background The serial interval is the period of time between symptom onset in the primary case and symptom onset in the secondary case. Understanding the serial interval is important for determining transmission dynamics of infectious diseases like COVID-19, including the reproduction number and secondary attack rates, which could influence control measures. Early meta-analyses of COVID-19 reported serial intervals of 5.2 days (95% CI: 4.9–5.5) for the original wild-type variant and 5.2 days (95% CI: 4.87–5.47) for Alpha variant. The serial interval has been shown to decrease over the course of an epidemic for other respiratory diseases, which may be due to accumulating viral mutations and implementation of more effective nonpharmaceutical interventions. We therefore aggregated the literature to estimate serial intervals for Delta and Omicron variants. Methods This study followed Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. A systematic literature search was conducted of PubMed, Scopus, Cochrane Library, ScienceDirect, and preprint server medRxiv for articles published from April 4, 2021, through May 23, 2023. Search terms were: (“serial interval” or “generation time”), (“Omicron” or “Delta”), and (“SARS-CoV-2” or “COVID-19”). Meta-analyses were done for Delta and Omicron variants using a restricted maximum-likelihood estimator model with a random effect for each study. Pooled average estimates and 95% confidence intervals (95% CI) are reported. Results There were 46,648 primary/secondary case pairs included for the meta-analysis of Delta and 18,324 for Omicron. Mean serial interval for included studies ranged from 2.3–5.8 days for Delta and 2.1–4.8 days for Omicron. The pooled mean serial interval for Delta was 3.9 days (95% CI: 3.4–4.3) (20 studies) and Omicron was 3.2 days (95% CI: 2.9–3.5) (20 studies). Mean estimated serial interval for BA.1 was 3.3 days (95% CI: 2.8–3.7) (11 studies), BA.2 was 2.9 days (95% CI: 2.7–3.1) (six studies), and BA.5 was 2.3 days (95% CI: 1.6–3.1) (three studies). Conclusions Serial interval estimates for Delta and Omicron were shorter than ancestral SARS-CoV-2 variants. More recent Omicron subvariants had even shorter serial intervals suggesting serial intervals may be shortening over time. This suggests more rapid transmission from one generation of cases to the next, consistent with the observed faster growth dynamic of these variants compared to their ancestors. Additional changes to the serial interval may occur as SARS-CoV-2 continues to circulate and evolve. Changes to population immunity (due to infection and/or vaccination) may further modify it.

Mesocyclops leuckarti is a zooplankton that is potentially suitable as a live food for freshwater fish larvae. Aquaculture farmers often struggled to create nutritious live feed to maximize the production of larval fish. This study aimed to determine the effects of different enrichments on life-table parameters, protein, lipid and fatty acid content of M. leuckarti when enriched with different dietary enrichments. In this study, five treatments for raising the copepod were compared: rice bran, soybean meal, Chlorella sp., Spirulina sp., and unenriched (control). The results showed that M. leuckarti after 16 days of cultivation enriched with rice bran produced a higher population density (53.3 ind/ml) and survival rate (97.4%) than when cultivated with any of the other diets. In terms of nutritional value, protein content was higher in M. leuckarti enriched with rice bran (52% DW) and soybean meal (53% DW). However, lipid content was highest in M. leuckarti enriched with rice bran (14% DW). Fatty acids, such as α -linolenic acid ALA (7.21%) and docosahexaenoic acid DHA (6.26%) were higher in M. leuckarti enriched with rice bran. Eicosapentaenoic acid EPA (7.16%) and arachidonic acid ARA (7.74%) were higher in M. leuckarti enriched with Chlorella sp. This study suggests that organic by-products are better sources for strengthening and improving the growth performance and life history of this copepod, and possibly also of zooplankton organisms in general. [ABSTRACT FROM AUTHOR]

In this report I examine tradeoffs involving body size, age, and resource allocation within the framework of the Equal Fitness Paradigm (EFP) in six species of plethodontid salamanders of the genus Desmognathus in two assemblages in the southern Blue Ridge Mountains of North Carolina. The species are representative of the three life-history modes associated with habitat utilization in Desmognathus, namely stream, streamside, and forest. The two assemblages include the largest and smallest members of the genus. Among species, I recorded a negative correlation between body size and relative offspring size, a positive correlation between body size and lifetime offspring number, but negative correlations between body size and both lifetime reproductive investment and productivity, as reflected in the decrease in body size with increasing relative offspring size. In comparing these trends with published data on variation in these parameters in animals generally, I conclude that desmognathan salamanders lie at the slow end of the fast–slow axis in the pace-of-life model of life-history evolution. I discuss possible population regulatory mechanisms that operate on these populations, as a function of life-history mode, with special emphasis on streamside species. I suggest that retention of a brief larval phase in streamside species reflects tradeoffs among dispersal-related traits, including survival and growth. [ABSTRACT FROM AUTHOR]

In recent years, a large number of microplastics (MPs) appeared in the aquatic environment, causing serious pollution. In order to study the influence of MP concentrations on freshwater zooplankton, polystyrene microspheres (PS) of 0.5 μm were used in this study as experimental reagents, and Moina macrocopa, which was dominant zooplankton in the Pearl River Basin of China, was selected as the experimental object. The experiment was divided into four treatment groups plus a control group, and it was conducted for 15 days. The treatment groups had MP concentrations of 10, 10², 10³ and 104 pieces/mL. The survival time, reproduction rate, the total offspring, and the time of first pregnancy of Moina macrocopa were counted every day, and the intrinsic growth rate, generation time, and net reproduction rate were calculated. The results showed that the survival time of Moina macrocopa decreased with the increase of the MP concentration, and the MP concentration had more influence on the reproduction rate. Except for the 10 pieces/mL treatment group, no reproduction occurred in other treatment groups, and the reproduction rate gradually decreased with the increase of age. The life table showed that only the control group and the 10 pieces/mL treatment group had an intrinsic growth rate, and the intrinsic growth rate of the treatment group was far lower than that of the control group. Our experimental results provide basic data and a theoretical basis for further understanding the toxic effects of MPs on freshwater zooplankton. [ABSTRACT FROM AUTHOR]

Demographic research utilizing vital rates and life tables is a standard aspect of planning protection and management strategies for wildlife populations. The Blackbuck Antilope cervicapra population at Point Calimere Wildlife Sanctuary, Tamil Nadu, has undergone fluctuations in recent decades. The cause remains elusive, and conservation efforts may be hampered by a lack of population data. This study aimed to estimate demographic parameters using population count and age-sex classification data collected for the years 2017-2020. The overall mean population estimate derived from line-transect distance sampling was 719, with annual estimates of 716, 727, 711, and 722 for the years 2017-2020 respectively. In total, 64% of Blackbucks counted were adults, 19% subadults, and 17% fawns. Mortality was highest for adult and subadult classes for the composite female class, and fawn mortality was 20%. The net reproductive rate (R0) was as low as 3.28 offspring per generation contrasted with a rather longer mean generation time (G) as 4.75 years. Thus, the study observes a decrease in Blackbuck numbers postulated in earlier research to be driven principally by a conglomerate of factors, including reduction of usable space and interspecific resource competition. Our findings provide a baseline demography of the species and highlights the value of long-term demographic monitoring of age sex classes to understand the evolution of life histories. [ABSTRACT FROM AUTHOR]

Climate change can affect the length and timing of seasons, which in turn can alter the time available for insects to complete their life cycles and successfully reproduce. Intraspecific hybridization between individuals from genetically distinct populations, or admixture, can boost fitness in populations experiencing environmental challenges. Admixture can particularly benefit small and isolated populations that may have high genetic load by masking deleterious alleles, thereby immediately increasing fitness, and also by increasing the genetic variation available for adaptive evolution. To evaluate the effects of admixture on populations exposed to a novel life cycle constraint, we used the red flour beetle, Tribolium castaneum, as a model system. Distinct laboratory lineages were kept isolated or mixed together to create populations containing 1–4 lineages. We then compared the fitness of admixed populations to 1‐lineage populations while subjecting them to a shortened generation time for three generations. Admixture did not influence fitness after two generations. In contrast, in the third generation, admixed populations had significantly greater fitness compared with 1‐lineage populations. The timing of the increase in fitness for the admixed populations suggests that adaptation to the novel environmental constraint occurred in the experimental populations. Our study highlights the importance of admixture for facilitating rapid adaptation to changes in seasonality, and more broadly to environmental change. [ABSTRACT FROM AUTHOR]

Wang et al. (2023) recently proposed an approach to infer the history of human generation intervals from changes in mutation profiles over time. As the relative proportions of different mutation types depend on the ages of parents, binning variants by the time they arose allows for the inference of changes in average paternal and maternal generation intervals. Applying this approach to published allele age estimates, Wang et al. (2023) inferred long-lasting sex differences in average generation times and surprisingly found that ancestral generation times of West African populations remained substantially higher than those of Eurasian populations extending tens of thousands of generations into the past. Here, we argue that the results and interpretations in Wang et al. (2023) are primarily driven by noise and biases in input data and a lack of validation using independent approaches for estimating allele ages. With the recent development of methods to reconstruct genome-wide gene genealogies, coalescence times, and allele ages, we caution that downstream analyses may be strongly influenced by uncharacterized biases in their output. [ABSTRACT FROM AUTHOR]

We analyzed the first 255 PCR-confirmed cases of monkeypox in Italy in 2022. Preliminary estimates indicate mean incubation period of 9.1 (95% CI 6.5–10.9) days, mean generation time of 12.5 (95% CI 7.5–17.3) days, and reproduction number among men who have sex with men of 2.43 (95% CI 1.82–3.26).

Background: The serial interval is the period of time between symptom onset in the primary case and symptom onset in the secondary case. Understanding the serial interval is important for determining transmission dynamics of infectious diseases like COVID-19, including the reproduction number and secondary attack rates, which could influence control measures. Early meta-analyses of COVID-19 reported serial intervals of 5.2 days (95% CI: 4.9–5.5) for the original wild-type variant and 5.2 days (95% CI: 4.87–5.47) for Alpha variant. The serial interval has been shown to decrease over the course of an epidemic for other respiratory diseases, which may be due to accumulating viral mutations and implementation of more effective nonpharmaceutical interventions. We therefore aggregated the literature to estimate serial intervals for Delta and Omicron variants. Methods: This study followed Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. A systematic literature search was conducted of PubMed, Scopus, Cochrane Library, ScienceDirect, and preprint server medRxiv for articles published from April 4, 2021, through May 23, 2023. Search terms were: ("serial interval" or "generation time"), ("Omicron" or "Delta"), and ("SARS-CoV-2" or "COVID-19"). Meta-analyses were done for Delta and Omicron variants using a restricted maximum-likelihood estimator model with a random effect for each study. Pooled average estimates and 95% confidence intervals (95% CI) are reported. Results: There were 46,648 primary/secondary case pairs included for the meta-analysis of Delta and 18,324 for Omicron. Mean serial interval for included studies ranged from 2.3–5.8 days for Delta and 2.1–4.8 days for Omicron. The pooled mean serial interval for Delta was 3.9 days (95% CI: 3.4–4.3) (20 studies) and Omicron was 3.2 days (95% CI: 2.9–3.5) (20 studies). Mean estimated serial interval for BA.1 was 3.3 days (95% CI: 2.8–3.7) (11 studies), BA.2 was 2.9 days (95% CI: 2.7–3.1) (six studies), and BA.5 was 2.3 days (95% CI: 1.6–3.1) (three studies). Conclusions: Serial interval estimates for Delta and Omicron were shorter than ancestral SARS-CoV-2 variants. More recent Omicron subvariants had even shorter serial intervals suggesting serial intervals may be shortening over time. This suggests more rapid transmission from one generation of cases to the next, consistent with the observed faster growth dynamic of these variants compared to their ancestors. Additional changes to the serial interval may occur as SARS-CoV-2 continues to circulate and evolve. Changes to population immunity (due to infection and/or vaccination) may further modify it. [ABSTRACT FROM AUTHOR]

Let R be a commutative Noetherian ring. We prove that if R is either an equidimensional finitely generated algebra over a perfect field, or an equidimensional equicharacteristic complete local ring with a perfect residue field, then the annihilator of the singularity category of R coincides with the Jacobian ideal of R up to radical. We establish a relationship between the annihilator of the singularity category of R and the cohomological annihilator of R under some mild assumptions. Finally, we give an upper bound for the dimension of the singularity category of an equicharacteristic excellent local ring with isolated singularity. This extends a result of Dao and Takahashi to non-Cohen–Macaulay rings. [ABSTRACT FROM AUTHOR]

The growth of bacterial populations has been described as a dynamic process of continuous reproduction and cell death. However, this is far from the reality. In a well fed, growing bacterial population, the stationary phase inevitably occurs, and it is not due to accumulated toxins or cell death. A population spends the most time in the stationary phase, where the phenotype of the cells alters from the proliferating ones, and only the colony forming unit (CFU) decreases after a while, not the total cell concentration. A bacterial population can be considered as a virtual tissue as a result of a specific differentiation process, in which the exponential-phase cells develop to stationary-phase cells and eventually reach the unculturable form. The richness of the nutrient had no effect on growth rate or on stationary cell density. The generation time seems not to be a constant value, but it depended on the concentration of the starter cultures. Inoculations with serial dilutions of stationary populations reveal a so-called minimal stationary cell concentration (MSCC) point, up to which the cell concentrations remain constant upon dilutions; that seems to be universal among unicellular organisms. [ABSTRACT FROM AUTHOR]

Increasing antimicrobial resistance has caused a great interest in natural products as alternatives or potentiators of antibiotics. The objective of this study was to isolate individual tannins from crude chestnut extract as well as to determine the influence of both crude extracts (tannic acid extract, chestnut extract) and individual pure tannins (gallic acid, vescalin, vescalagin, castalin, castalagin) on the growth of Gram-positive Staphylococcus aureus bacteria. Their antibacterial activity was monitored by measuring the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) as well as the duration of the lag phase, growth rate and generation time. The effect of growth medium strength on the MIC of different tannins was also investigated. Bacterial growth was followed spectrophotometrically, and MIC values were determined by the microdilution method. The MIC values of various isolated compounds allowed us to determine the bioactive compounds and their contribution to antimicrobial activity. It was found that MIC values increase with increasing growth medium strength and that the lag phase lengthens with increasing tannin concentrations, while the growth rates decrease. Comparing the results of the two studies, the antimicrobial activity of tannins against S. aureus was not as pronounced as in the case of E. coli, which may indicate that a different mechanism of action is responsible for the antimicrobial effects of tannins on Gram-positive than on Gram-negative bacteria, or that a different mechanism is more pronounced. [ABSTRACT FROM AUTHOR]

Although control measures to tackle bovine tuberculosis (bTB) in cattle have been successful in many parts of Europe, this disease has not been eradicated in areas where Mycobacterium bovis circulates in multi-host systems. Here we analyzed the resurgence of 11 M. bovis genotypes (defined based on spoligotyping and MIRU-VNTR) detected in 141 farms between 2007 and 2019, in an area of Southwestern France where wildlife infection was also detected from 2012 in 65 badgers. We used a spatially-explicit model to reconstruct the simultaneous diffusion of the 11 genotypes in cattle farms and badger populations. Effective reproduction number R was estimated to be 1.34 in 2007–2011 indicating a self-sustained M. bovis transmission by a maintenance community although within-species Rs were both < 1, indicating that neither cattle nor badger populations acted as separate reservoir hosts. From 2012, control measures were implemented, and we observed a decrease of R below 1. Spatial contrasts of the basic reproduction ratio suggested that local field conditions may favor (or penalize) local spread of bTB upon introduction into a new farm. Calculation of generation time distributions showed that the spread of M. bovis has been more rapid from cattle farms (0.5–0.7 year) than from badger groups (1.3–2.4 years). Although eradication of bTB appears possible in the study area (since R < 1), the model suggests it is a long-term prospect, because of the prolonged persistence of infection in badger groups (2.9–5.7 years). Supplementary tools and efforts to better control bTB infection in badgers (including vaccination for instance) appear necessary. [ABSTRACT FROM AUTHOR]

Since the mid‐2010s, Phytophthora infestans clones that have been dominant in Western Europe from the beginning of the 21st century, for example, EU_13_A2, EU_6_A1 and EU_1_A1, are being replaced by several other emerging clones, including EU_37_A2. The objective of this study was to determine whether the main drivers for the success of EU_37_A2 in Western Europe are associated with decreased fungicide sensitivity, increased virulence and/or aggressiveness. Axenic P. infestans cultures were sampled in the 2016 and 2017 growing seasons from potato crops in France and the United Kingdom. Amongst these, four genotypes were identified: EU_37_A2, EU_13_A2, EU_1_A1 and EU_6_A1. Although a wide range of fluazinam sensitivity was found amongst individual isolates, clonal lines EU_13_A2 and EU_37_A2 showed decreased sensitivity to fluazinam. EU_37_A2 overcame the R5 differential cultivar more often than isolates of EU_1_A1 or EU_6_A1. However, this does not explain the competitive advantage of EU_37_A2 over the virulent EU_13_A2. The fittest genotype, as measured by aggressiveness under controlled conditions, was EU_6_A1, followed by EU_37_A2, EU_13_A2 and then EU_1_A1. EU_37_A2 isolates also showed a shorter latent period than either EU_6_A1 or EU_13_A2, which could favour its long‐term persistence. Overall, the data suggest that the emergence of EU_37_A2 in Western Europe was driven by its resistance to a then‐major fungicide and shorter generation time. This conclusion is further supported by the fact that EU_37_A2 emergence was slowed by the progressive reduction in the use of fluazinam as a single active ingredient in the years following its initial detection. [ABSTRACT FROM AUTHOR]

Examining temporal changes in the growth and generation time of fish species can be valuable for understanding population responses to different management measures and environmental conditions. Atlantic herring (Clupea harengus-Linnaeus, 1758) is an ecologically and commercially important pelagic forage fish species that occupies the southern Gulf of St. Lawrence. Here, we developed von Bertalanffy growth curves and estimated yearly values of generation time for NAFO Division 4TVn Atlantic herring for the years from 1988 to 2021. The results indicate a temporal reduction in the growth and generation time of both spring and fall spawning herring. Over the time series, the generation time of spring and fall spawners reduced by approximately 1 and 2 years, respectively. Furthermore, the average generation time of spring spawners across the time series (6.23 years (95% CI: 5.78–6.85 years)) was approximately 1 year lower than that of fall spawners (7.52 years (6.82–8.34 years)). Overall, the findings of this study can be used to better inform stock assessments and rebuilding plans for 4TVn spring and fall spawning Atlantic herring and highlight the importance of examining temporal trends in growth and generation time for more effective management of fish stocks. [ABSTRACT FROM AUTHOR]

Species across a wide range of taxa and habitats are shifting phenological events in response to climate change. While advances are common, shifts vary in magnitude and direction within and among species, and the basis for this variation is relatively unknown. We examine previously suggested patterns of variation in phenological shifts in order to understand the cue–response mechanisms that underlie phenological change. Here, we review what is known about the mechanistic basis for nine factors proposed to predict phenological change (latitude, elevation, habitat type, trophic level, migratory strategy, ecological specialization, species’ seasonality, thermoregulatory mode, and generation time). We find that many studies either do not identify a specific underlying mechanism or do not evaluate alternative mechanistic hypotheses, limiting the ability of scientists to predict future responses to global change with accuracy. We present a conceptual framework that emphasizes a critical distinction between environmental (cue-driven) and organismal (response-driven) mechanisms causing variation in phenological shifts and discuss how this distinction can reduce confusion in the field and improve predictions of future phenological change.

I present a simulation model on vital statistics, absolute abundance (N, total number of individuals that ever lived) and preservation rate (p, minimum number of fossils known divided by N) of Tyrannosaurus rex. It is based on a published age‐structured population model that assumes a reptile or bird‐like reproduction for T. rex to estimate its age‐specific survival rates. My model applies input variables and equations from a recently published model on N and p. This model yielded 2.5 billion T. rex individuals (N) and one fossil per 80 million individuals (p). The average N values calculated by my model were at minimum 27.6% and p values at maximum 361.5% that of a previous model and uncertainties in all output variables were always larger in my model. The equation on output variable 'population density' introduced the largest uncertainty to N and p. The output variable 'generation time' differed the most between models, but for N and p, the huge size of the input area modelled and geological longevity minimized this difference. Unlike my model, the generation time as well as life expectancies, gross reproduction rates, and reproductive values of individuals calculated from the previous model all strongly contradicted our current understanding of the biology of T. rex and of other theropods. Their values also disagreed with those of large extant reptiles, birds and mammals. All of these shortcomings of the previous model favour the assessment of individual and population characteristics of T. rex and of other extinct species using my model. [ABSTRACT FROM AUTHOR]

Temporal autocorrelation in environmental conditions influences population dynamics through its effects on vital rates. However, a comprehensive understanding of how and to what extent temporal autocorrelation shapes population dynamics is still lacking because most empirical studies have unrealistically assumed that environmental conditions are temporally independent. Mast seeding is a biological event characterized by highly fluctuating and synchronized seed production at the tree population scale as well as a marked negative temporal autocorrelation. In the current context of global change, mast seeding events are expected to become more frequent, leading to strengthened negative temporal autocorrelations and thereby amplified cyclicality in mast seeding dynamics. Theory predicts that population growth rates are maximized when the environmental cyclicality of consumer resources and their generation times are closely matched. To test this prediction, we took advantage of the long-term monitoring of a wild boar population, a widespread seed consumer species characterized by a short generation time (∼2 years). As expected, simulations indicated that its stochastic population growth rate increased as mast seeding dynamics became more negatively autocorrelated. Our findings demonstrate that accounting for temporal autocorrelations in environmental conditions relative to the generation time of the focal population is required, especially under conditions of global warming, where the cyclicality in resource dynamics is likely to change. [ABSTRACT FROM AUTHOR]

Quantitative information on epidemiological quantities such as the incubation period and generation time of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants is scarce. We analysed a dataset collected during contact tracing activities in the province of Reggio Emilia, Italy, throughout 2021. We determined the distributions of the incubation period for the Alpha and Delta variants using information on negative polymerase chain reaction tests and the date of last exposure from 282 symptomatic cases. We estimated the distributions of the intrinsic generation time using a Bayesian inference approach applied to 9724 SARS-CoV-2 cases clustered in 3545 households where at least one secondary case was recorded. We estimated a mean incubation period of 4.9 days (95% credible intervals, CrI, 4.4–5.4) for Alpha and 4.5 days (95% CrI 4.0–5.0) for Delta. The intrinsic generation time was estimated to have a mean of 7.12 days (95% CrI 6.27–8.44) for Alpha and of 6.52 days (95% CrI 5.54–8.43) for Delta. The household serial interval was 2.43 days (95% CrI 2.29–2.58) for Alpha and 2.74 days (95% CrI 2.62–2.88) for Delta, and the estimated proportion of pre-symptomatic transmission was 48–51% for both variants. These results indicate limited differences in the incubation period and intrinsic generation time of SARS-CoV-2 variants Alpha and Delta compared to ancestral lineages. [ABSTRACT FROM AUTHOR]

Recent studies have suggested that the human germline mutation rate and spectrum evolve rapidly. Variation in generation time has been linked to these changes, though its contribution remains unclear. We develop a framework to characterize temporal changes in polymorphisms within and between populations, while controlling for the effects of natural selection and biased gene conversion. Application to the 1000 Genomes Project dataset reveals multiple independent changes that arose after the split of continental groups, including a previously reported, transient elevation in TCC>TTC mutations in Europeans and novel signals of divergence in C>Gand T>A mutation rates among population samples. We also find a significant difference between groups sampled in and outside of Africa in old T>C polymorphisms that predate the out-of-Africa migration. This surprising signal is driven by TpG>CpG mutations and stems in part from mis-polarized CpG transitions, which are more likely to undergo recurrent mutations. Finally, by relating the mutation spectrum of polymorphisms to parental age effects on de novo mutations, we show that plausible changes in the generation time cannot explain the patterns observed for different mutation types jointly. Thus, other factors – genetic modifiers or environmental exposures – must have had a non-negligible impact on the human mutation landscape.

Quantitative information on epidemiological quantities such as the incubation period and generation time of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants is scarce. We analysed a dataset collected during contact tracing activities in the province of Reggio Emilia, Italy, throughout 2021. We determined the distributions of the incubation period for the Alpha and Delta variants using information on negative polymerase chain reaction tests and the date of last exposure from 282 symptomatic cases. We estimated the distributions of the intrinsic generation time using a Bayesian inference approach applied to 9724 SARS-CoV-2 cases clustered in 3545 households where at least one secondary case was recorded. We estimated a mean incubation period of 4.9 days (95% credible intervals, CrI, 4.4–5.4) for Alpha and 4.5 days (95% CrI 4.0–5.0) for Delta. The intrinsic generation time was estimated to have a mean of 7.12 days (95% CrI 6.27–8.44) for Alpha and of 6.52 days (95% CrI 5.54–8.43) for Delta. The household serial interval was 2.43 days (95% CrI 2.29–2.58) for Alpha and 2.74 days (95% CrI 2.62–2.88) for Delta, and the estimated proportion of pre-symptomatic transmission was 48–51% for both variants. These results indicate limited differences in the incubation period and intrinsic generation time of SARS-CoV-2 variants Alpha and Delta compared to ancestral lineages. [ABSTRACT FROM AUTHOR]

Physiological characterization show that all the strains have more growth in nitrogen enriched medium compared to nitrogen deficient medium. The growth measurement in terms of dry weight indicated that genus Westiellopsis has produced the maximum biomass. Therefore it has more growth rate and minimum generation time. [ABSTRACT FROM AUTHOR]

We analyzed the first 255 PCR-confirmed cases of monkeypox in Italy in 2022. Preliminary estimates indicate mean incubation period of 9.1 (95% CI 6.5-10.9) days, mean generation time of 12.5 (95% CI 7.5-17.3) days, and reproduction number among men who have sex with men of 2.43 (95% CI 1.82-3.26). [ABSTRACT FROM AUTHOR]

We used published data from outbreak investigations of monkeypox virus clade I in the Democratic Republic of the Congo to estimate the distributions of critical epidemiological parameters. We estimated a mean incubation period of 9.9 days (95% credible interval [CrI] 8.5-11.5 days) and a mean generation time of 17.2 days (95% CrI 14.1-20.9 days) or 11.3 days (95% CrI 9.4-14.0 days), depending on the considered dataset. Presymptomatic transmission was limited. Those estimates suggest generally slower transmission dynamics in clade I than in clade IIb. The time-varying reproduction number for clade I in the Democratic Republic of the Congo was estimated to be below the epidemic threshold in the first half of 2024. However, in the South Kivu Province, where the newly identified subclade Ib has been associated with sustained human-to-human transmission, we estimated an effective reproduction number above the epidemic threshold (95% CrI 0.96-1.27).

Iteroparous species may reproduce at many different ages, resulting in a reproductive dispersion that affects the damping of population perturbations, and varies among life histories. Since generation time (Tc) is known to capture aspects of life‐history variation, such as life‐history speed, does Tc also determine reproductive dispersion (S) or damping time (τ)? Using phylogenetically corrected analyses on 633 species of animals and plants, we find, firstly, that reproductive dispersion S scales isometrically with Tc. Secondly, and unexpectedly, we find that the damping time (τ) does not scale isometrically with generation time, but instead changes only as Tcb with b<1 (also, there is a similar scaling with S). This non‐isometric scaling implies a novel demographic contrast: increasing generation times correspond to a proportional increase in reproductive dispersion, but only to a slower increase in the damping time. Thus, damping times are partly decoupled from the slow‐fast continuum, and are determined by factors other than allometric constraints. [ABSTRACT FROM AUTHOR]

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Summary: Background: Starting from the final months of 2021, the SARS-CoV-2 Omicron variant expanded globally, swiftly replacing Delta, the variant that was dominant at the time. Many uncertainties remain about the epidemiology of Omicron; here, we aim to estimate its generation time. Methods: We used a Bayesian approach to analyze 23,122 SARS-CoV-2 infected individuals clustered in 8903 households as determined from contact tracing operations in Reggio Emilia, Italy, throughout January 2022. We estimated the distribution of the intrinsic generation time (the time between the infection dates of an infector and its secondary cases in a fully susceptible population), realized household generation time, realized serial interval (time between symptom onset of an infector and its secondary cases), and contribution of pre-symptomatic transmission. Findings: We estimated a mean intrinsic generation time of 6.84 days (95% credible intervals, CrI, 5.72–8.60), and a mean realized household generation time of 3.59 days (95%CrI: 3.55–3.60). The household serial interval was 2.38 days (95%CrI 2.30–2.47) with about 51% (95%CrI 45–56%) of infections caused by symptomatic individuals being generated before symptom onset. Interpretation: These results indicate that the intrinsic generation time of the SARS-CoV-2 Omicron variant might not have shortened as compared to previous estimates on ancestral lineages, Alpha and Delta, in the same geographic setting. Like for previous lineages, pre-symptomatic transmission appears to play a key role for Omicron transmission. Estimates in this study may be useful to design quarantine, isolation and contact tracing protocols and to support surveillance (e.g., for the accurate computation of reproduction numbers). Funding: The study was partially funded by EU grant 874850 MOOD.

The growth of bacterial populations has been described as a dynamic process of continuous reproduction and cell death. However, this is far from the reality. In a well fed, growing bacterial population, the stationary phase inevitably occurs, and it is not due to accumulated toxins or cell death. A population spends the most time in the stationary phase, where the phenotype of the cells alters from the proliferating ones, and only the colony forming unit (CFU) decreases after a while, not the total cell concentration. A bacterial population can be considered as a virtual tissue as a result of a specific differentiation process, in which the exponential-phase cells develop to stationary-phase cells and eventually reach the unculturable form. The richness of the nutrient had no effect on growth rate or on stationary cell density. The generation time seems not to be a constant value, but it depended on the concentration of the starter cultures. Inoculations with serial dilutions of stationary populations reveal a so-called minimal stationary cell concentration (MSCC) point, up to which the cell concentrations remain constant upon dilutions; that seems to be universal among unicellular organisms.

Examining temporal changes in the growth and generation time of fish species can be valuable for understanding population responses to different management measures and environmental conditions. Atlantic herring (Clupea harengus-Linnaeus, 1758) is an ecologically and commercially important pelagic forage fish species that occupies the southern Gulf of St. Lawrence. Here, we developed von Bertalanffy growth curves and estimated yearly values of generation time for NAFO Division 4TVn Atlantic herring for the years from 1988 to 2021. The results indicate a temporal reduction in the growth and generation time of both spring and fall spawning herring. Over the time series, the generation time of spring and fall spawners reduced by approximately 1 and 2 years, respectively. Furthermore, the average generation time of spring spawners across the time series (6.23 years (95% CI: 5.78–6.85 years)) was approximately 1 year lower than that of fall spawners (7.52 years (6.82–8.34 years)). Overall, the findings of this study can be used to better inform stock assessments and rebuilding plans for 4TVn spring and fall spawning Atlantic herring and highlight the importance of examining temporal trends in growth and generation time for more effective management of fish stocks.

Common lilac is an important flowering shrub that accounts for ≈$20 million of sales in the U.S. nursery industry. Cultivar improvement in common lilac has been ongoing for centuries, yet little research has focused on shortening the multiple-year juvenility period for lilacs and the subsequent time required between breeding cycles. The practice of direct-sowing of immature “green” seed has been shown to reduce juvenility in some woody plants, but it has not been reported for common lilac. This study investigated the effects of seed maturity [weeks after pollination (WAP)], pregermination seed treatment (direct-sown vs. cold-stratified), and postgermination seedling chilling on the germination percentage, subsequent plant growth, and time to flower on lilac seedlings. All seedlings were derived from the female parent ‘Ludwig Spaeth’ and the male parent ‘Angel White’. Seeds harvested at 15 and 20 WAP resulted in 58% (sd ± 9.9%) and 80% (sd ± 9.0%) germination, respectively, which were similar to that of dry seed collected at 20 WAP with stratification (62% ± 4.2%). Seedlings from the green seed collected at 15 and 20 WAP were also approximately three-times taller than those of dry seed groups DS1, DS2, and DS3 after the first growing season. Over the next two growing seasons, there were no differences in seedling height across all treatments. Flowering occurred at the beginning of the fourth season and without differences among treatments. These results indicate that the collection and direct sowing of immature, green seed can be used to successfully grow lilac seedlings, but that they do not reduce the juvenility period. However, this method can provide more vegetative growth in year one to observe early vegetative traits such as leaf color, and it can provide more material for DNA extraction to support molecular research.

background. The effective reproduction number Re(t) is a critical measure of epidemic potential. Re(t) can be calculated in near real time using an incidence time series and the generation time distribution: the time between infection events in an infector-infectee pair. In calculating Re(t), the generation time distribution is often approximated by the serial interval distribution: the time between symptom onset in an infector-infectee pair. However, while generation time must be positive by definition, serial interval can be negative if transmission can occur before symptoms, such as in covid-19, rendering such an approximation improper in some contexts. methods. We developed a method to infer the generation time distribution from parametric definitions of the serial interval and incubation period distributions. We then compared estimates of Re(t) for covid-19 in the Greater Toronto Area of Canada using: negative-permitting versus non-negative serial interval distributions, versus the inferred generation time distribution. results. We estimated the generation time of covid-19 to be Gamma-distributed with mean 3.99 and standard deviation 2.96 days. Relative to the generation time distribution, non-negative serial interval distribution caused overestimation of Re(t) due to larger mean, while negative-permitting serial interval distribution caused underestimation of Re(t) due to larger variance. implications. Approximation of the generation time distribution of covid-19 with non-negative or negative-permitting serial interval distributions when calculating Re(t) may result in over or underestimation of transmission potential, respectively.

The distribution of the generation time (the interval between individuals becoming infected and transmitting the virus) characterises changes in the transmission risk during SARS-CoV-2 infections. Inferring the generation time distribution is essential to plan and assess public health measures. We previously developed a mechanistic approach for estimating the generation time, which provided an improved fit to data from the early months of the COVID-19 pandemic (December 2019-March 2020) compared to existing models (Hart et al., 2021). However, few estimates of the generation time exist based on data from later in the pandemic. Here, using data from a household study conducted from March to November 2020 in the UK, we provide updated estimates of the generation time. We considered both a commonly used approach in which the transmission risk is assumed to be independent of when symptoms develop, and our mechanistic model in which transmission and symptoms are linked explicitly. Assuming independent transmission and symptoms, we estimated a mean generation time (4.2 days, 95% credible interval 3.3–5.3 days) similar to previous estimates from other countries, but with a higher standard deviation (4.9 days, 3.0–8.3 days). Using our mechanistic approach, we estimated a longer mean generation time (5.9 days, 5.2–7.0 days) and a similar standard deviation (4.8 days, 4.0–6.3 days). As well as estimating the generation time using data from the entire study period, we also considered whether the generation time varied temporally. Both models suggest a shorter mean generation time in September-November 2020 compared to earlier months. Since the SARS-CoV-2 generation time appears to be changing, further data collection and analysis is necessary to continue to monitor ongoing transmission and inform future public health policy decisions.

Background: Coronavirus disease 2019 (COVID-19) has caused a heavy disease burden globally. The impact of process and timing of data collection on the accuracy of estimation of key epidemiological distributions are unclear. Because infection times are typically unobserved, there are relatively few estimates of generation time distribution.Methods: We developed a statistical framework to jointly estimate generation time and incubation period from human-to-human transmission pairs, accounting for sampling biases. We applied the framework on 80 laboratory-confirmed human-to-human transmission pairs in China. We further inferred the infectiousness profile, serial interval distribution, proportions of presymptomatic transmission, and basic reproduction number (R0) for COVID-19.Results: The estimated mean incubation period was 4.8 days (95% confidence interval [CI], 4.1-5.6), and mean generation time was 5.7 days (95% CI, 4.8-6.5). The estimated R0 based on the estimated generation time was 2.2 (95% CI, 1.9-2.4). A simulation study suggested that our approach could provide unbiased estimates, insensitive to the width of exposure windows.Conclusions: Properly accounting for the timing and process of data collection is critical to have correct estimates of generation time and incubation period. R0 can be biased when it is derived based on serial interval as the proxy of generation time. [ABSTRACT FROM AUTHOR]

The growth kinetics of Lactobacillus acidophilus in black rice milk, white rice milk and MRS Broth were calculated by applying the experimental data to the Gompertz equation using DataFit software. The survival of L. acidophilus in black rice and white rice milk was monitored during storage (4°C, 20 days). The shortest lag phase duration (1.45 h) and the highest maximum population density (7.48 log CFU/mL) were in black rice milk (P <0.05). The generation time in black rice milk (1.31 h) was longer than in white rice milk (0.58 h) but shorter than in MRS Broth (2.22 h, P <0.05). L. acidophilus population declined in both milk at 4°C, but higher in black rice than white rice at the end of the storage period. It was concluded that black rice supports the growth of L. acidophilus compared to white rice and MRS Broth while contributing to its survival during cold storage. [ABSTRACT FROM AUTHOR]

The aim of this work was to characterize the response of cyanobacterium Synechocystis PCC 6803 and green microalgae Chlorella sorokiniana UTEX 1230 to 100 Gy gamma irradiation with respect to generation time and their content in valuable biochemical compounds. The 60Co irradiation was carried out as previously described (MOISESCU et al., 2019) but the biological material (both the cyanobacterium and the microalga) was prepared in a slightly different way. Experimental results showed that in 100 Gy gamma irradiated Synechocystis PCC 6803 there are differences with respect to the growth rate, compared to the control. For Chlorella sorokiniana UTEX 1230, the experimental results showed that in 100 Gy gamma irradiated cells there are differences in the growth rate, total proteins, carotenes, total lipids and chlorophylls (i.e., chlorophyll a and b as well as biomass, when the cultures where scaled up from 50mL to 10 L). The results are discussed given the potential biotechnological applications, as well as from a fundamental scientific point of view. [ABSTRACT FROM AUTHOR]

ABSTRACT Bloodstream infections (BSI) are a major public health burden due to high mortality rates and the cost of treatment. The impact of BSI is further compounded by a rise in antibiotic resistance among Gram-negative species associated with these infections. Escherichia coli, Serratia marcescens, Klebsiella pneumoniae, Enterobacter hormaechei, Citrobacter freundii, and Acinetobacter baumannii are all common causes of BSI, which can be recapitulated in a murine model. The objective of this study was to characterize infection kinetics and bacterial replication rates during bacteremia for these six pathogens to gain a better understanding of bacterial physiology during infection. Temporal observations of bacterial burdens of the tested species demonstrated varied abilities to establish colonization in the spleen, liver, or kidney. K. pneumoniae and S. marcescens expanded rapidly in the liver and kidney, respectively. Other organisms, such as C. freundii and E. hormaechei, were steadily cleared from all three target organs throughout the infection. In situ replication rates measured by whole-genome sequencing of bacterial DNA recovered from murine spleens demonstrated that each species was capable of sustained replication at 24 h postinfection, and several species demonstrated