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Background: Age estimation plays a crucial role in identifying an unknown individual in the event of any mass disaster or crime. One of the important noninvasive procedures that may have an impact on determining an individual's age is exfoliative cytology. Aim and Objective: Exfoliated buccal mucosa cells were used in the study to determine the participant's age by assessing the changes in nuclear diameter (ND), nuclear–cytoplasmic (N: C) ratio, and cell diameter (CD). Materials and Methods: With the help of a moistened wooden spatula and a light scraping motion, buccal smears were taken from 100 healthy and normal individuals across various age groups. The samples were then preserved with 95% ethanol and stained using ultrafast Papanicolaou stain. Cell and nuclear diameter were measured for each of these cells using the ImageJ software, and N: C was calculated from the two parameters. The N: C was calculated from CD and ND for each subject. One-way ANOVA tests were used for statistical analysis. Results: A significant difference in the diameter of cell and nucleus with the individual's age (P < 0.05) was noticed. The N: C ratio reduces with increasing age but is not consistent. Conclusion: Buccal smears show age-related alterations that could be utilized as an effective tool for age estimation.

Bacterial growth and behavior have been studied in microgravity in the past, but little focus has been directed to cell size despite its impact on a myriad of processes, including biofilm formation, which is impactful regarding crew health. To interrogate this characteristic, supernatant aliquots of P. aeruginosa cultured on different materials and media on board the International Space Station (ISS) as part of the Space Biofilms Project were analyzed. For that experiment, P. aeruginosa was grown in microgravity—with matching Earth controls—in modified artificial urine medium (mAUMg-high Pi) or LB Lennox supplemented with KNO3, and its formation of biofilms on six different materials was assessed. After one, two, and three days of incubation, the ISS crew terminated subsets of the experiment by fixation in paraformaldehyde, and aliquots of the supernatant were used for the planktonic cell size study presented here. The measurements were obtained post-flight through the use of phase contrast microscopy under oil immersion, a Moticam 10+ digital camera, and the FIJI image analysis program. Statistical comparisons were conducted to identify which treatments caused significant differences in cell dimensions using the Kruskal–Wallis and Dunn tests. There were statistically significant differences as a function of material present in the culture in both LBK and mAUMg-high Pi. Along with this, the data were also grouped by gravitational condition, media, and days of incubation. Comparison of planktonic cells cultured in microgravity showed reduced cell length (from 4% to 10% depending on the material) and diameter (from 1% to 10% depending on the material) with respect to their matching Earth controls, with the caveat that the cultures may have been at different points in their growth curve at a given time. In conclusion, smaller cells were observed on the cultures grown in microgravity, and cell size changed as a function of incubation time and the material upon which the culture grew. We describe these changes here and possible implications for human space travel in terms of crew health and potential applications. [ABSTRACT FROM AUTHOR]

Background: Age estimation plays a crucial role in identifying an unknown individual in the event of any mass disaster or crime. One of the important noninvasive procedures that may have an impact on determining an individual's age is exfoliative cytology. Aim and Objective: Exfoliated buccal mucosa cells were used in the study to determine the participant's age by assessing the changes in nuclear diameter (ND), nuclear-cytoplasmic (N: C) ratio, and cell diameter (CD). Materials and Methods: With the help of a moistened wooden spatula and a light scraping motion, buccal smears were taken from 100 healthy and normal individuals across various age groups. The samples were then preserved with 95% ethanol and stained using ultrafast Papanicolaou stain. Cell and nuclear diameter were measured for each of these cells using the ImageJ software, and N: C was calculated from the two parameters. The N: C was calculated from CD and ND for each subject. One-way ANOVA tests were used for statistical analysis. Results: A significant difference in the diameter of cell and nucleus with the individual's age (P < 0.05) was noticed. The N: C ratio reduces with increasing age but is not consistent. Conclusion: Buccal smears show age-related alterations that could be utilized as an effective tool for age estimation. [ABSTRACT FROM AUTHOR]

Bacterial growth and behavior have been studied in microgravity in the past, but little focus has been directed to cell size despite its impact on a myriad of processes, including biofilm formation, which is impactful regarding crew health. To interrogate this characteristic, supernatant aliquots of P. aeruginosa cultured on different materials and media on board the International Space Station (ISS) as part of the Space Biofilms Project were analyzed. For that experiment, P. aeruginosa was grown in microgravity—with matching Earth controls—in modified artificial urine medium (mAUMg-high Pi) or LB Lennox supplemented with KNO3, and its formation of biofilms on six different materials was assessed. After one, two, and three days of incubation, the ISS crew terminated subsets of the experiment by fixation in paraformaldehyde, and aliquots of the supernatant were used for the planktonic cell size study presented here. The measurements were obtained post-flight through the use of phase contrast microscopy under oil immersion, a Moticam 10+ digital camera, and the FIJI image analysis program. Statistical comparisons were conducted to identify which treatments caused significant differences in cell dimensions using the Kruskal–Wallis and Dunn tests. There were statistically significant differences as a function of material present in the culture in both LBK and mAUMg-high Pi. Along with this, the data were also grouped by gravitational condition, media, and days of incubation. Comparison of planktonic cells cultured in microgravity showed reduced cell length (from 4% to 10% depending on the material) and diameter (from 1% to 10% depending on the material) with respect to their matching Earth controls, with the caveat that the cultures may have been at different points in their growth curve at a given time. In conclusion, smaller cells were observed on the cultures grown in microgravity, and cell size changed as a function of incubation time and the material upon which the culture grew. We describe these changes here and possible implications for human space travel in terms of crew health and potential applications.

Harmful cyanobacterial blooms in eutrophic water bodies pose a major threat to the environment and to human health. The morphological functional traits of cyanobacteria play important roles in maintaining their competitive advantages. To explore the regulatory mechanisms of the morphological functional traits of different bloom-forming cyanobacteria, we performed a one-year-long phytoplankton survey from November 2016 to October 2017 in Lake Chaohu, China. The colony size and cell diameter of the dominant cyanobacteria were measured, and their relationships were analyzed. The results showed that Dolichospermum flos-aquae and Microcystis aeruginosa were the dominant cyanobacteria in the lake. Microcystis was the dominant species during the summer; the growth of Dolichospermum growth surpassed that of Microcystis, and Dolichospermum became the dominant species in the late autumn, winter and spring. From winter to spring, the colony size of Dolichospermum decreased from 222.25 μm to 10.51 μm, and the individual cell diameter increased from 6.5 μm to 7.4 μm. From summer to autumn, Dolichospermum showed enlarged colony sizes and reduced cell diameters. The Microcystis colony size increased from 83.71 μm in the spring to 196.71 μm in the summer and autumn, while cells diameter remained essentially at 3–4 μm from March to October in Lake Chaohu. The relationship between colony size and cell diameter in Dolichospermum was significantly positive, while that of Microcystis was not significant. These results suggest that Dolichospermum may maintain biomass through a trade-off between cell diameter and colony size, and that a flexible morphological regulatory mechanism exists. This study seeks to improve our understanding of how bloom-forming cyanobacteria maintain their dominance by regulating their morphological traits. [ABSTRACT FROM AUTHOR]

Abstract Among bacteria and archaea, maximum relative growth rate, cell diameter, and genome size are widely regarded as important influences on ecological strategy. Via the most extensive data compilation so far for these traits across all clades and habitats, we ask whether they are correlated and if so how. Overall, we found little correlation among them, indicating they should be considered as independent dimensions of ecological variation. Nor was correlation evident within particular habitat types. A weak nonlinearity (6% of variance) was found whereby high maximum growth rates (temperature‐adjusted) tended to occur in the midrange of cell diameters. Species identified in the literature as oligotrophs or copiotrophs were clearly separated on the dimension of maximum growth rate, but not on the dimensions of genome size or cell diameter.

Quantitative traits such as maximum growth rate and cell radial diameter are one facet of ecological strategy variation across bacteria and archaea. Another facet is substrate-use pathways, such as iron reduction or methylotrophy. Here, we ask how these two facets intersect, using a large compilation of data for culturable species and examining seven quantitative traits (genome size, signal transduction protein count, histidine kinase count, growth temperature, temperature-adjusted maximum growth rate, cell radial diameter and 16S rRNA operon copy number). Overall, quantitative trait variation within groups of organisms possessing a particular substrate-use pathway was very broad, outweighing differences between substrate-use groups. Although some substrate-use groups had significantly different means for some quantitative traits, standard deviation of quantitative trait values within each substrate-use pathway mostly averaged between 1.6 and 1.8 times larger than standard deviation across group means. Most likely, this wide variation reflects ecological strategy: for example, fast maximum growth rate is likely to express an early successional or copiotrophic strategy, and maximum growth varies widely within most substrate-use pathways. In general, it appears that these quantitative traits express different and complementary information about ecological strategy, compared with substrate use. [ABSTRACT FROM AUTHOR]

The paper deals with the description of method, proposed by authors, that determining the essential geometric characteristics of the metal foam structure with using of the analytical imaging software. Method use economically available technical apparatus and software with emphasis on maximum consideration of the measurement uncertainty by Kline-McClintock method. The image analysis used three kinds of metal foams with a pore density of 10 to 40 pores per inch. The most important parameter - the size of a metal foam cell ranged from 1,165 mm (for 40 PPI) through a 2,262 mm (for 20 PPI) to 5,660 mm (for 10 PPI).

Interdependent partitions located in three-dimensional porous structures pose a problem for understanding the flow field, which differs significantly from the flow in traditional porous media. The structure of open cell foam requires the use of various flow laws (Darcy, Forchmeyer, or the direct solution of the Navier–Stokes equations, because the value of medium permeability is unknown in advance). The purpose of this work is to determine the effect of smoothing in the open cell foam structure on the resistance of the medium. As a characteristic of the resistance, the pressure drop has been considered for the given gas flow rate. The main parameters of porous medium are the cell diameter, the fiber diameter, and the porosity. Thus, we have determined the parameter that makes the greatest contribution to the pressure drop change. The computer model of open cell foam has been presented as an ordered set of intersecting spheres. For hydrodynamic calculation, we have used the ANSYS Fluent software package. We have compared the calculation results of pressure drop with the experimental data of other authors. It has been established that the model of a porous medium using of automatic smoothing of all the faces (performed by AutoCAD package) provides the biggest pressure drop at a fixed value of the porosity of the foam compare to the model with smoothed faces manually and the model without smoothing. Thus, the approximation of an elementary porous cell substantially distorts the flow field. It is not good in the detailed simulation of the open cell foam material. In addition, we have made calculations of the pressure drop with different fixed parameters of the medium – porosity, cell diameter, and fiber diameter of the medium. The calculations have shown that hydrodynamics is determined by the fiber diameter of the porous structure.

Among bacteria and archaea, maximum relative growth rate, cell diameter, and genome size are widely regarded as important influences on ecological strategy. Via the most extensive data compilation so far for these traits across all clades and habitats, we ask whether they are correlated and if so how. Overall, we found little correlation among them, indicating they should be considered as independent dimensions of ecological variation. Nor was correlation evident within particular habitat types. A weak nonlinearity (6% of variance) was found whereby high maximum growth rates (temperature‐adjusted) tended to occur in the midrange of cell diameters. Species identified in the literature as oligotrophs or copiotrophs were clearly separated on the dimension of maximum growth rate, but not on the dimensions of genome size or cell diameter. [ABSTRACT FROM AUTHOR]

Summary: Wood density is the product of carbon allocation for structural growth and reflects the trade‐off between mechanical support and water conductivity. We tested a conceptual framework based on the assumption that micro‐density depends on direct and indirect relationships with endogenous and exogenous factors.The dynamics of wood formation, including timings and rates of cell division, cell enlargement, and secondary wall deposition, were assessed from microcores collected weekly between 2002 and 2016 from five black spruce stands located along a latitudinal gradient in Quebec, Canada. Cell anatomy and micro‐density were recorded by anatomical analyses and X‐ray measurements.Our structural equation model explained 80% of micro‐density variation within the tree‐ring with direct effects of wall thickness (σ = 0.61), cell diameter (σ = −0.51), and photoperiod (σ = −0.26). Wood formation dynamics had an indirect effect on micro‐density. Micro‐density increased under longer periods of cell‐wall deposition and shorter durations of enlargement.Our results fill a critical gap in understanding the relationships underlying micro‐density variation in conifers. We demonstrated that short‐term responses to environmental variations could be overridden by plastic responses that modulate cell differentiation. Our results point to wood formation dynamics as a reliable predictor of carbon allocation in trees. [ABSTRACT FROM AUTHOR]

Harmful cyanobacterial blooms in eutrophic water bodies pose a major threat to the environment and to human health. The morphological functional traits of cyanobacteria play important roles in maintaining their competitive advantages. To explore the regulatory mechanisms of the morphological functional traits of different bloom-forming cyanobacteria, we performed a one-year-long phytoplankton survey from November 2016 to October 2017 in Lake Chaohu, China. The colony size and cell diameter of the dominant cyanobacteria were measured, and their relationships were analyzed. The results showed that Dolichospermum flos-aquae and Microcystis aeruginosa were the dominant cyanobacteria in the lake. Microcystis was the dominant species during the summer; the growth of Dolichospermum growth surpassed that of Microcystis, and Dolichospermum became the dominant species in the late autumn, winter and spring. From winter to spring, the colony size of Dolichospermum decreased from 222.25 μm to 10.51 μm, and the individual cell diameter increased from 6.5 μm to 7.4 μm. From summer to autumn, Dolichospermum showed enlarged colony sizes and reduced cell diameters. The Microcystis colony size increased from 83.71 μm in the spring to 196.71 μm in the summer and autumn, while cells diameter remained essentially at 3–4 μm from March to October in Lake Chaohu. The relationship between colony size and cell diameter in Dolichospermum was significantly positive, while that of Microcystis was not significant. These results suggest that Dolichospermum may maintain biomass through a trade-off between cell diameter and colony size, and that a flexible morphological regulatory mechanism exists. This study seeks to improve our understanding of how bloom-forming cyanobacteria maintain their dominance by regulating their morphological traits.

A recent study proposed the novel classification of the family Mycobacteriaceae based on the genome analysis of core proteins in 150 Mycobacterium species. The results from these analyses supported the existence of five distinct monophyletic groups within the genus Mycobacterium. That is, Mycobacterium has been divided into two novel genera for rapid grower Mycobacteroides and Mycolicibacterium, and into three genera for slow grower Mycolicibacter, Mycolicibacillus, and an emended genus Mycobacterium, which include all the major human pathogens. Here, cryo-TEM examinations of 1,816 cells of 31 species (34 strains) belonging to the five novel genera were performed. The fundamental morphological properties of every single cell, such as cell diameter, cell length, cell perimeter, cell circularity, and aspect ratio were measured and compared between these genera. In 50 comparisons on the five parameters between any two genera, only five comparisons showed “non-significant” differences. That is, there are non-significant differences between slow grower genus Mycolicibacillus and genus Mycobacterium in average cell diameter (p = 0.15), between rapid grower genus Mycobacteroides and slow grower genus Mycobacterium in average cell length (p > 0.24), between genus Mycobacteroides and genus Mycobacterium (p > 0.68) and between genus Mycolicibacter and genus Mycolicibacillus (p > 0.11) in average cell perimeter, and between genus Mycolicibacterium and genus Mycobacterium in circularity (p > 0.73). The other 45 comparisons showed significant differences between the genera. Genus Mycobacteroides showed the longest average cell diameter, whereas the genus Mycolicibacter showed the shortest average diameter. Genus Mycolicibacterium showed the most extended average cell length, perimeter, and aspect ratio, whereas the genus Mycolicibacillus showed the shortest average cell length, perimeter, and aspect ratio. Genus Mycolicibacillus showed the highest average cell circularity, whereas genus Mycobacterium showed the lowest average cell circularity. These fundamental morphological data strongly support the new classification in the family Mycobacteriaceae, and this classification is rational and effective in the study of the members of the family Mycobacteriaceae. Because both the genus Mycolicibacterium and the genus Mycobacterium contain many species and showed larger significant standard deviations in every parameter, these genera may be divided into novel genera which show common genotype and phenotypes in morphology and pathogenicity.

New insights into the intra-annual dynamics of tree-ring formation can improve our understanding of tree-growth response to environmental conditions at high-resolution time scales. Obtaining this information requires, however, a weekly monitoring of wood formation, sampling that is extremely time-intensive and scarcely feasible over vast areas. Estimating the timing of cambial and xylem differentiation by modeling thus represents an interesting alternative for obtaining this important information by other means. Temporal dynamics of cambial divisions can be extracted from the daily tree-ring growth rate computed by the Vaganov–Shashkin (VS) simulation model, assuming that cell production is tightly linked to tree-ring growth. Nonetheless, these predictions have yet to be compared with direct observations of wood development, i.e., via microcoring, over a long time span. We tested the performance of the VS model by comparing the observed and predicted timing of wood formation in black spruce [Picea mariana (Mill.)]. We obtained microcores over 15 years at 5 sites along a latitudinal gradient in Quebec (Canada). The measured variables included cell size and the timing of cell production and differentiation. We calibrated the VS model using daily temperature and precipitation recorded by weather stations located on each site. The predicted and observed timing of cambial and enlarging cells were highly correlated (R2 = 0.8); nonetheless, we detected a systematic overestimation in the predicted timing of cambial cells, with predictions delayed by 1–20 days compared with observations. The growth rate of cell diameter was correlated with the predicted growth rate assigned to each cambial cell, confirming that cell diameter developmental dynamics have the potential to be inferred by the tree-ring growth curve of the VS model. Model performances decrease substantially in estimating the end of wood formation. The systematic errors suggest that the actual relationships implemented in the model are unable to explain the phenological events in autumn. The mismatch between the observed and predicted timing of wood formation in black spruce within our study area can be reduced by better adapting the VS model to wet sites, a context for which this model has been rarely used.

A recent study proposed the novel classification of the family Mycobacteriaceae based on the genome analysis of core proteins in 150 Mycobacterium species. The results from these analyses supported the existence of five distinct monophyletic groups within the genus Mycobacterium. That is, Mycobacterium has been divided into two novel genera for rapid grower Mycobacteroides and Mycolicibacterium , and into three genera for slow grower Mycolicibacter , Mycolicibacillus , and an emended genus Mycobacterium , which include all the major human pathogens. Here, cryo-TEM examinations of 1,816 cells of 31 species (34 strains) belonging to the five novel genera were performed. The fundamental morphological properties of every single cell, such as cell diameter, cell length, cell perimeter, cell circularity, and aspect ratio were measured and compared between these genera. In 50 comparisons on the five parameters between any two genera, only five comparisons showed "non-significant" differences. That is, there are non-significant differences between slow grower genus Mycolicibacillus and genus Mycobacterium in average cell diameter (p = 0.15), between rapid grower genus Mycobacteroides and slow grower genus Mycobacterium in average cell length (p > 0.24), between genus Mycobacteroides and genus Mycobacterium (p > 0.68) and between genus Mycolicibacter and genus Mycolicibacillus (p > 0.11) in average cell perimeter, and between genus Mycolicibacterium and genus Mycobacterium in circularity (p > 0.73). The other 45 comparisons showed significant differences between the genera. Genus Mycobacteroides showed the longest average cell diameter, whereas the genus Mycolicibacter showed the shortest average diameter. Genus Mycolicibacterium showed the most extended average cell length, perimeter, and aspect ratio, whereas the genus Mycolicibacillus showed the shortest average cell length, perimeter, and aspect ratio. Genus Mycolicibacillus showed the highest average cell circularity, whereas genus Mycobacterium showed the lowest average cell circularity. These fundamental morphological data strongly support the new classification in the family Mycobacteriaceae , and this classification is rational and effective in the study of the members of the family Mycobacteriaceae. Because both the genus Mycolicibacterium and the genus Mycobacterium contain many species and showed larger significant standard deviations in every parameter, these genera may be divided into novel genera which show common genotype and phenotypes in morphology and pathogenicity. [ABSTRACT FROM AUTHOR]

New insights into the intra-annual dynamics of tree-ring formation can improve our understanding of tree-growth response to environmental conditions at high-resolution time scales. Obtaining this information requires, however, a weekly monitoring of wood formation, sampling that is extremely time-intensive and scarcely feasible over vast areas. Estimating the timing of cambial and xylem differentiation by modeling thus represents an interesting alternative for obtaining this important information by other means. Temporal dynamics of cambial divisions can be extracted from the daily tree-ring growth rate computed by the Vaganov–Shashkin (VS) simulation model, assuming that cell production is tightly linked to tree-ring growth. Nonetheless, these predictions have yet to be compared with direct observations of wood development, i.e., via microcoring, over a long time span. We tested the performance of the VS model by comparing the observed and predicted timing of wood formation in black spruce [ Picea mariana (Mill.)]. We obtained microcores over 15 years at 5 sites along a latitudinal gradient in Quebec (Canada). The measured variables included cell size and the timing of cell production and differentiation. We calibrated the VS model using daily temperature and precipitation recorded by weather stations located on each site. The predicted and observed timing of cambial and enlarging cells were highly correlated (R 2 = 0.8); nonetheless, we detected a systematic overestimation in the predicted timing of cambial cells, with predictions delayed by 1–20 days compared with observations. The growth rate of cell diameter was correlated with the predicted growth rate assigned to each cambial cell, confirming that cell diameter developmental dynamics have the potential to be inferred by the tree-ring growth curve of the VS model. Model performances decrease substantially in estimating the end of wood formation. The systematic errors suggest that the actual relationships implemented in the model are unable to explain the phenological events in autumn. The mismatch between the observed and predicted timing of wood formation in black spruce within our study area can be reduced by better adapting the VS model to wet sites, a context for which this model has been rarely used. [ABSTRACT FROM AUTHOR]

Aim: The purpose of the investigation was to analyze the relationships between the defensiveness, diameter of the worker's baby cell and the production of honey bees (Apis mellifera) in the highlands of Ecuador. Methods: 75 bee colonies were evaluated in the months of March-April, May-July (during the production stage) and September, at altitudes between 2 600 and 3 274 m a.s.l. To each colony the defense was determined through the flag technique, the diameter of the cells was obtained through the measurement of ten cells of the worker's honeycomb and the honey production was determined by difference of weight. Results: An average value of 14 stingers/min was found, the maximum and minimum values for this behavioral trait were 47 and 4 stingers/min; for the diameter of the 10 cells, an average of 5.28 cm was found, with maximum and minimum values of 5.50 and 4.95 cm, respectively. A significant correlation was identified (-0.358 **), which indicates that colonies with greater defensiveness had a smaller cell diameter. The production showed an average of 25.08 kg of honey / colony, unrelated to the variables under study. Conclusions: There were no relationships between production and the other variables under study, so it would be possible to select less defensive colonies and with larger cell diameters, without affecting honey production. [ABSTRACT FROM AUTHOR]

Background and Aims Secondary growth is a process related to the formation of new cells that increase in size and wall thickness during xylogenesis. Temporal dynamics of wood formation influence cell traits, in turn affecting cell patterns across the tree ring. We verified the hypothesis that cell diameter and cell wall thickness are positively correlated with the duration of their differentiation phases. Methods Histological sections were produced by microcores to assess the periods of cell differentiation in black spruce [ Picea mariana (Mill.) B.S.P.]. Samples were collected weekly between 2002 and 2016 from a total of 50 trees in five sites along a latitudinal gradient in Quebec (Canada). The intra-annual temporal dynamics of cell differentiation were estimated at a daily scale, and the relationships between cell traits and duration of differentiation were fitted using a modified von Bertalanffy growth equation. Key Results At all sites, larger cell diameters and cell wall thicknesses were observed in cells that experienced a longer period of differentiation. The relationship was a non-linear, decreasing trend that occasionally resulted in a clear asymptote. Overall, secondary wall deposition lasted longer than cell enlargement. Earlywood cells underwent an enlargement phase that lasted for 12 d on average, while secondary wall thickness lasted 15 d. Enlargement in latewood cells averaged 7 d and secondary wall deposition occurred over an average of 27 d. Conclusions Cell size across the tree ring is closely connected to the temporal dynamics of cell formation. Similar relationships were observed among the five study sites, indicating shared xylem formation dynamics across the entire latitudinal distribution of the species.The duration of cell differentiation is a key factor involved in cell growth and wall thickening of xylem, thereby determining the spatial variation of cell traits across the tree ring. [ABSTRACT FROM AUTHOR]

The paper deals with the description of method, proposed by authors, that determining the essential geometric characteristics of the metal foam structure with using of the analytical imaging software. Method use economically available technical apparatus and software with emphasis on maximum consideration of the measurement uncertainty by Kline-McClintock method. The image analysis used three kinds of metal foams with a pore density of 10 to 40 pores per inch. The most important parameter - the size of a metal foam cell ranged from 1,165 mm (for 40 PPI) through a 2,262 mm (for 20 PPI) to 5,660 mm (for 10 PPI). [ABSTRACT FROM AUTHOR]

Plants exhibit morphological and anatomical adaptations to cope the environmental constraints of their habitat. How can mechanisms for adapting to contrasting environmental conditions change the patterns of tree rings formation? In this study, we explored differences in climatic conditions of permafrost and non-permafrost zones and assessed their influence on radial growth and wood traits of Larix gmelinii Rupr (Rupr) and Larix sibirica L., respectively. We quantified the contribution of xylem cell anatomy to the tree-ring width variability. Comparison of the anatomical tree-ring parameters over the period 1963–2011 was tested based on non-parametric Mann-Whitney U test. The generalized linear modeling shows the common dependence between TRW and the cell structure characteristics in contrasting environments, which can be defined as non-specific to external conditions. Thus, the relationship between the tree-ring width and the cell production in early- and latewood are assessed as linear, whereas the dependence between the radial cell size in early- and latewood and the tree-ring width becomes significantly non-linear for both habitats. Moreover, contribution of earlywood (EW) and latewood (LW) cells to the variation of TRW (in average 56.8% and 24.4% respectively) was significantly higher than the effect of cell diameters (3.3% (EW) and 17.4% (LW)) for the environments. The results show that different larch species from sites with diverging climatic conditions converge towards similar xylem cell structures and relationships between xylem production and cell traits. The work makes a link between climate and tree-ring structure, and promotes a better understanding the anatomical adaptation of larch species to local environment conditions.

Voltage-gated K+ (KV) currents play a crucial role in regulating pain by controlling neuronal excitability, and are divided into transient A-type currents (IA) and delayed rectifier currents (IK). The dorsal root ganglion (DRG) neurons are heterogeneous and the subtypes of KV currents display different levels in distinct cell sizes. To observe correlations of the subtypes of KV currents with DRG cell sizes, KV currents were recorded by whole-cell patch clamp in freshly isolated mouse DRG neurons. Results showed that IA occupied a high proportion in KV currents in medium- and large-diameter DRG neurons, whereas IK possessed a larger proportion of KV currents in small-diameter DRG neurons. A lower correlation was found between the proportion of IA or IK in KV currents and cell sizes. These data suggest that IA channels are mainly expressed in medium and large cells and IK channels are predominantly expressed in small cells. [ABSTRACT FROM AUTHOR]

Aims: The present study was undertaken as a baseline study to evaluate the nuclear diameter (ND), cell diameter (CD) and nuclear-cytoplasmic ratio (N:C) and their variation with age in normal buccal smears of female subjects. Materials and Methods: Buccal smears were collected from 400 apparently healthy individuals. After fixation in 95% alcohol, the smears were stained using the standard Papanicolaou laboratory procedure. The CD and ND were measured using a stage micrometer and an ocular micrometer. Statistical analysis of the data was performed using the one-way analysis of variance to evaluate the difference in the ND, CD and N:C with age in females. Multiple range tests by Tukey-honestly significant difference procedure were performed to evaluate the significance between various age groups. Results: The results showed an increase in ND and CD from the 5-10 age groups to 15-35 age groups. In the 15-35 age groups, there was a decline in ND and CD when comparing the first and the second half of the menstrual cycle, but the difference was not significant. There was further decline in ND and CD in the 45-60 age groups. Variations were also seen in ratio N: C. Pattern of exfoliation also varied in each age group. Conclusion: Age-related alterations are observed in buccal smears.

Extreme climate events are of key importance for forest ecosystems. However, both the inherent infrequency, stochasticity and multiplicity of extreme climate events, and the array of biological responses, challenges investigations. To cope with the long life cycle of trees and the paucity of the extreme events themselves, our inferences should be based on long-term observations. In this context, tree rings and the related xylem anatomical traits represent promising sources of information, due to the wide time perspective and quality of the information they can provide.Here we test, on two high-elevation conifers (Larix decidua and Picea abies sampled at 2100 m a.s.l. in the Eastern Alps), the associations among temperature extremes during the growing season and xylem anatomical traits, specifically the number of cells per ring (CN), cell wall thickness (CWT) and cell diameter (CD). To better track the effect of extreme events over the growing season, tree rings were partitioned in 10 sectors. Climate variability has been reconstructed, for 1800-2011 at monthly resolution and for 1926-2011 at daily resolution, by exploiting the excellent availability of very long and high quality instrumental records available for the surrounding area, and taking into account the relationship between meteorological variables and site topographical settings.Summer temperature influenced anatomical traits of both species, and tree-ring anatomical profiles resulted as being associated to temperature extremes. Most of the extreme values in anatomical traits occurred with warm (positive extremes) or cold (negative) conditions. However, 0% - 34% of occurrences did not match a temperature extreme event. Specifically, CWT and CN extremes were more clearly associated to climate than CD, which presented a bias to track cold extremes.Dendroanatomical analysis, coupled to high-quality daily-resolved climate records, seems a promising approach to study the effects of extreme events on trees, but further investigations are needed to improve our comprehension of the critical role of such elusive events in forest ecosystems.

Objective: The present study was undertaken to evaluate the nuclear diameter (ND), cell diameter (CD) and nuclear-cytoplasmic ratio (N:C) and their variation with age and sex in normal gingival smears. Study Design: Gingival smears were collected from 320 apparently healthy individuals. After fixation in 95% alcohol, the smears were stained using standard papanicolaou laboratory procedure. The cell and nuclear diameters were measured using image analysis software (KS lite 2.0). Statistical analysis of the data was done using one-way ANOVA, Students ′t′ test and Tukey-HSD procedure. Results: The results showed an increase in ND from the 1-20 group to 21-40 age group in males. Above 40 years, there was a decrease in ND. In females, the ND was high in 21-40 age group; and then from 41 years, ND gradually decreased but the difference was not significant. The CD in males and females was low in the 1-20 age group and then it gradually increased. However, the difference was not significant between the ages 20 and 60 years. After 60, there was a decrease in CD. Similar changes are also seen in the ratio N:C in both males and females. The ND, CD and N:C irrespective of the age were high in females. The difference in CD was insignificant, except in the 0-20 age group, where females had significantly more cell diameters. Irrespective of the gender, the ND, CD and N:C increased from 0-20 age group to 20-40 age group. After 40, there is a steady decrease in ND, CD and N:C. Conclusion: Age-related and sex-related alterations are observed in gingival smears.

We hypothesized that cells with different diameter have different division rates, which could affect lipid productivity (lipid content × biomass productivity). In the present work we assessed the influence of cell diameter, as a sorting parameter, on both biomass and lipid productivity of Chlorococcum littorale . Prior to sorting, cells were grown in a batch-wise nitrogen run-out including a long nitrogen depleted phase (N −) to stop cell division, thus only having vegetative cells (Pre-sorting). Cell sorting was done at the end of this N − phase using FACS (fluorescence assisted cell sorting) based on forward scatter as a proxy for diameter (size ranges (μm): 5–6 (small), 8–9 (medium), 11–14 (large) and 5–14 (control)). The sorting was done in 2 pools: multiple-cell (100 cells) and single-cell. After sorting, cells were recovered under low-light for 2 weeks, and used to start the Post-sorting experiment (analogous to Pre-sorting). The populations derived from different sorted pools, single-cell and multiple-cell, showed similar size distributions after re-growth. No difference was observed in biomass and lipid productivities among Post-sorting cells and when compared to Pre-sorting cells under nitrogen depletion. We concluded that cellular size had no effect on both biomass and lipid productivity of C. littorale . [ABSTRACT FROM AUTHOR]