Tree densities and sex ratios in breeding populations of dioecious Central Amazonian Myristicaceae

1990 ◽  
Vol 6 (2) ◽  
pp. 239-248 ◽  
Author(s):  
David D. Ackerly ◽  
Judy M. Rankin-De-Merona ◽  
William A. Rodrigues

ABSTRACTThe densities of the breeding populations and the sex of all flowering individuals were recorded for five dioecious canopy tree species of Central Amazonian Myristicaceae, in 11 study areas of the Minimum Critical size of Ecosystems Project totalling 22.5 ha. Adult population densities were extremely low, ranging from 0.38 to 1.61 ha–1 for the five species studied. In a 10 ha study plot the mean distance to the nearest flowering conspecific ranged from 48 to 100 m, while the mean distance to the nearest opposite sex conspecific was 147 m. The two most abundant species, Iryanthera macrophylla and Virola calophylla, both showed male-biased sex ratios, of 23:9 and 20:6, respectively. The size class distribution of males, females and non-flowering individuals in V. calophylla suggests that earlier reproductive maturation of male plants may provide a partial explanation for this bias. In I. macrophylla, since 95% of the individuals were observed flowering, the observed ratio is representative of the population, and may be caused by sex shifts from male to female. The low reproductive densities, combined with the skewed sex ratios and overlapping generations of these species, create very small effective breeding populations, placing species such as these at great risk in the face of deforestation and habitat fragmentation.

2014 ◽  
Vol 10 (6) ◽  
pp. 20140148 ◽  
Author(s):  
Amanda C. Hahn ◽  
Claire I. Fisher ◽  
Lisa M. DeBruine ◽  
Benedict C. Jones

The sex ratio of the local population influences mating-related behaviours in many species. Recent experiments show that male-biased sex ratios increase the amount of financial resources men will invest in potential mates, suggesting that sex ratios influence allocation of mating effort in humans. To investigate this issue further, we tested for effects of cues to the sex ratio of the local population on the motivational salience of attractiveness in own-sex and opposite-sex faces. We did this using an effort-based key-press task, in which the motivational salience of facial attractiveness was assessed in samples of faces in which the ratio of male to female images was manipulated. The motivational salience of attractive opposite-sex, but not own-sex, faces was greater in the own-sex-biased (high competition for mates) than in the opposite-sex-biased (low competition for mates) condition. Moreover, this effect was not modulated by participant sex. These results present new evidence that sex ratio influences human mating-related behaviours. They also present the first evidence that the perceived sex ratio of the local population may modulate allocation of mating effort in women, as well as men.


Author(s):  
David L Freytag ◽  
Michael G Alfertshofer ◽  
Konstantin Frank ◽  
Dmitry V Melnikov ◽  
Nicholas Moellhoff ◽  
...  

Abstract Background Our understanding of the functional anatomy of the face is constantly improving. To date, it is unclear whether the anatomic location of the line of ligaments has any functional importance during normal facial movements such as smiling. Objectives It is the objective of the present study to identify differences in facial movements between the medial and lateral midface by means of skin vector displacement analyses derived from 3D imaging and to further ascertain whether the line of ligaments has both a structural and functional significance in these movements. Methods The study sample consisted of 21 healthy volunteers (9 females & 12 males) of Caucasian ethnic background with a mean age of 30.6 (8.3) years and a mean BMI of 22.57 (2.5) kg/m 2. 3D images of the volunteers’ faces in repose and during smiling (Duchenne type) were taken. 3D imaging-based skin vector displacement analyses were conducted. Results The mean horizontal skin displacement was 0.08 (2.0) mm in the medial midface (lateral movement) and was -0.08 (1.96) mm in the lateral midface (medial movement) (p = 0.711). The mean vertical skin displacement (cranial movement of skin toward the forehead/temple) was 6.68 (2.4) mm in the medial midface whereas it was 5.20 (2.07) mm in the lateral midface (p = 0.003). Conclusions The results of this study provide objective evidence for an antagonistic skin movement between the medial and the lateral midface. The functional boundary identified by 3D imaging corresponds to the anatomic location of the line of ligaments.


2021 ◽  
pp. 140349482110100
Author(s):  
Ralph Catalano

Aims: To determine whether differences between Norway’s and Sweden’s attempts to contain SARS-CoV-2 infection coincided with detectably different changes in their all-cause mortality sex ratios. Measuring temporal variation in the all-cause mortality sex ratio before and during the pandemic in populations exposed to different constraints on risky behavior would allow us to better anticipate changes in the ratio and to better understand its association with infection control strategies. Methods: I apply time Box–Jenkins modeling to 262 months of pre-pandemic mortality sex ratios to arrive at counterfactual values of 10 intra-pandemic ratios. I compare counterfactual to observed values to determine if intra-pandemic ratios differed detectably from those expected as well as whether the Norwegian and Swedish differences varied from each other. Results: The male to female mortality sex ratio in both Norway and Sweden increased during the pandemic. I, however, find no evidence that the increase differed between the two countries despite their different COVID-19 containment strategies. Conclusion: Societal expectations of who will die during the COVID-19 pandemic will likely be wrong if they assume pre-pandemic mortality sex ratios because the intra-pandemic ratios appear, at least in Norway and Sweden, detectably higher. The contribution of differences in policies to reduce risky behavior to those higher ratios appears, however, small.


1950 ◽  
Vol 40 (3) ◽  
pp. 227-232 ◽  
Author(s):  
E. M. Crook ◽  
D. J. Watson

The CO2 concentration in the atmosphere of a potato clamp varied between 0·06 and 0·86%. The sum of CO2 and oxygen concentrations remained approximately constant at 21%. The CO2 concentration increased with time from December to April. This was attributed to increase in the rate of respiration of the potatoes caused by rise of temperature. Wind blowing in the direction normal to the face of the clamp reduced the COa concentration, presumably by causing external air to flow through the clamp coverings. A multiple regression of CO2 concentration on temperature of the potatoes at the time of sampling, and on the mean component of wind velocity normal to the clamp face estimated over a period of 3 hr. before the time of sampling, accounted for 64% of the variance between sampling occasions.Unsaturated compounds were detected in the clamp atmosphere by absorption in bromine; the concentration of these, expressed as ethylene, varied between 0·004 and 0·025%.The magnitude of CO2 accumulation and oxygen depletion in the clamp atmosphere was too small to produce effects of practical importance on the storage behaviour of the potatoes. If the unsaturated compounds were ethylene, the concentration present was sufficient to cause appreciable retardation of sprouting.


2021 ◽  
pp. 1-11
Author(s):  
Michel Garenne ◽  
Susan Thurstans ◽  
André Briend ◽  
Carmel Dolan ◽  
Tanya Khara ◽  
...  

Abstract The study investigates sex differences in the prevalence of undernutrition in sub-Saharan Africa. Undernutrition was defined by Z-scores using the CDC-2000 growth charts. Some 128 Demographic and Health Surveys (DHS) were analysed, totalling 700,114 children under-five. The results revealed a higher susceptibility of boys to undernutrition. Male-to-female ratios of prevalence averaged 1.18 for stunting (height-for-age Z-score <−2.0); 1.01 for wasting (weight-for-height Z-score <−2.0); 1.05 for underweight (weight-for-age Z-score <−2.0); and 1.29 for concurrent wasting and stunting (weight-for-height and height-for-age Z-scores <−2.0). Sex ratios of prevalence varied with age for stunting and concurrent wasting and stunting, with higher values for children age 0–23 months and lower values for children age 24–59 months. Sex ratios of prevalence tended to increase with declining level of mortality for stunting, underweight and concurrent wasting and stunting, but remained stable for wasting. Comparisons were made with other anthropometric reference sets (NCHS-1977 and WHO-2006), and the results were found to differ somewhat from those obtained with CDC-2000. Possible rationales for these patterns are discussed.


2019 ◽  
Vol 48 (6) ◽  
pp. 1526-1534
Author(s):  
Sarah L. Chen ◽  
David R. Maldonado ◽  
Cammille C. Go ◽  
Cynthia Kyin ◽  
Ajay C. Lall ◽  
...  

Background: There is a plethora of literature on outcomes after hip arthroscopic surgery in the adult population; however, outcomes in the adolescent population have not been as widely reported. Additionally, as adolescents represent a very active population, it is imperative to understand their athletic activity and return to sport after hip arthroscopic surgery. Purpose: To analyze patient-reported outcomes (PROs) after hip arthroscopic surgery in adolescents (aged 10-19 years) and present a return-to-sport analysis in the athletic adolescent subgroup. Study Design: Systematic review; Level of evidence, 4. Methods: The PubMed, Embase, and Cochrane databases were searched according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines to identify articles that reported PROs after hip arthroscopic surgery in adolescents. The standardized mean difference was calculated to compare the effect size of hip arthroscopic surgery on various PROs. For the athletic subgroup, a return-to-sport summary was also provided. Results: Ten studies, with 618 adolescent hips and a collective study period of December 2004 to February 2015, were included in this systematic review. Across all studies, the mean age was 15.8 years (range, 11.0-19.9 years), and female patients composed approximately 56.7% of the entire cohort. The mean follow-up was 34.5 months (range, 12-120 months). The modified Harris Hip Score (mHHS) was reported in 9 studies, and at latest follow-up, scores were excellent in 4 studies (range, 90-95) and good in the remaining 5 studies (range, 82.1-89.6). All adolescents also showed significant improvement on the Non-Arthritic Hip Score (NAHS), the Hip Outcome Score–Activities of Daily Living (HOS-ADL), the HOS–Sport-Specific Subscale (HOS-SSS), the physical component of the 12-Item Short Form Health Survey (SF-12P), a visual analog scale for pain (VAS), and both versions of the International Hip Outcome Tool (iHOT-12 and iHOT-33) at latest follow-up ( P < .05). Further, mean improvements reported in all studies surpassed reported values of the minimal clinically important difference and patient acceptable symptomatic state for the mHHS, HOS-ADL, HOS-SSS, and iHOT-33. Finally, the collective return-to-sport rate among athletic adolescents was 84.9%. Conclusion: In the setting of labral tears and femoroacetabular impingement, hip arthroscopic surgery can safely be performed in adolescents and leads to significant functional improvement. Furthermore, athletic adolescents return to sport at high levels after hip arthroscopic surgery.


Sports ◽  
2018 ◽  
Vol 6 (4) ◽  
pp. 118
Author(s):  
Edem Appiah-Dwomoh ◽  
Anja Carlsohn ◽  
Frank Mayer

Long-distance race car drivers are classified as athletes. The sport is physically and mentally demanding, requiring long hours of practice. Therefore, optimal dietary intake is essential for health and performance of the athlete. The aim of the study was to evaluate dietary intake and to compare the data with dietary recommendations for athletes and for the general adult population according to the German Nutrition Society (DGE). A 24-h dietary recall during a competition preparation phase was obtained from 16 male race car drivers (28.3 ± 6.1 years, body mass index (BMI) of 22.9 ± 2.3 kg/m2). The mean intake of energy, nutrients, water and alcohol was recorded. The mean energy, vitamin B2, vitamin E, folate, fiber, calcium, water and alcohol intake were 2124 ± 814 kcal/day, 1.3 ± 0.5 mg/day, 12.5 ± 9.5 mg/day, 231.0 ± 90.9 ug/day, 21.4 ± 9.4 g/day, 1104 ± 764 mg/day, 3309 ± 1522 mL/day and 0.8 ± 2.5 mL/day respectively. Our study indicated that many of the nutrients studied, including energy and carbohydrate, were below the recommended dietary intake for both athletes and the DGE.


2017 ◽  
Vol 4 (S) ◽  
pp. 100
Author(s):  
M.I. Muradov ◽  
K.B. Mukhamedkerim ◽  
A. ABaiguzeva ◽  
K.E. Kazantaev ◽  
D.Zh. Koshkarbaev

Background: To provide quantitative objective data demonstrating the longevity and amount of volume augmentation in the fatty dystrophy of the facial tissue obtained with autologous lipofilling.   Methods: In our clinic had been operated 8 patients for last 2 years with fatty dystrophy of the facial tissue. A prospective analysis of all patients who underwent at our private practice and were followed up for at least 1,5 year. Surgery was performed under general anesthesia it is necessary for clear results tissue correction. We based on the literature has seen numerous clinical reports highlighting the benefits of autologous fat transfer for face from that areas, fat was collected from the abdomen (most frequently used donor site), hips, outer thighs (saddle-bags), internal knee or thigh, with quantitative volume measurements evaluating the amount of postoperative volume change.   Results: Twenty eight patients were included in the study. The mean follow-up time was 18 months. The mean amount of autologous fat injected into each face region was 10-70 mL. Hypercorrection was performed after 3 months and it was 20-50% of the initial injected fat volume. Overall, the mean absolute volume augmentation measured at their last (after 6 month) post operative visit was 10-25%. There was variability between patients in the volume amount and percentage that remained. The resorption process was observed in two patients after 6 month. We made correction with hyaluronic acid and silicone implants.   Conclusion: To our knowledge, this study is the first clinical quantification in our practise of autologous fat transfer and/or grafting in the literature that provides definitive evidence on the amount as well as the resultant longevity in the face. Autologous fat transfer to the face has definite long-term volume augmentation results. On average, approximately 25-35% of the injected volume remains at 18 months. However, some variability exists in the percentage of  volume that remains that may require a touch-up procedure.


Author(s):  
Saeedeh Shirdel ◽  
◽  
Setareh Esmaeeli ◽  
Kaveh Alavi ◽  
Pezhman Ghaemmaghami ◽  
...  

Objective: Verbal fluency is a cognitive function that can be easily assessed in bedside and provide useful data for clinical assessment of a variety of cognitive functions. We decided to provide a standardized test for the assessment of verbal fluency in Persian language, including both phonemic and semantic fluency subtests. Method: First, three letters (P, D, and Sh) and three categories (animals, fruits, and objects of kitchen) were selected based on a pilot study and a panel of specialists. Then, we selected 500 Persian speaking participants (47.8% male) that were 18 to 65 years old via convenient sampling from general population. Participants were stratified according to age, gender, and education. They performed the verbal fluency test. Results: The mean number of generated words in letter fluency and semantic fluency (±SD) were 8.3±4.1 and 18.0±5.5, respectively. Age, educational level, and mother tongue were associated with letter fluency. Semantic fluency was associated with age, gender, education level, and mother tongue. Conclusion: For a more reliable clinical assessment, we suggest to use all of the three letters and three semantic categories for each subject, calculate the mean of the produced words and compare them with the suggested cut-points provided for each subcategory. Age was negatively correlated with the number of generated words in letter fluency (r=-0.33; p<0.001) and semantic fluency tasks (r=-0.26; p<0.001). In letter fluency task, there was not a statistically significant difference between males and females according to the number of generated words (P=0.057). However, in semantic fluency, female participants generated more words (p=0.005). Mother tongue (Farsi) showed a significant effect both on letter fluency (t=5.55, p<0.001) and semantic fluency (t=9.41, p<0.001). Level of education had a significant association with both letter fluency (F=117.23, p<0.001) and semantic fluency (F=64.48, p<0.001).


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