Browse

1 - 10 of 307 items :

  • Evolutionary Biology x
Clear All

Abstract

Malnutrition among adolescents is an important public health issue in India. The aim of the present study was to assess nutritional status and body composition characteristics of adolescent girls and their interrelationships with physical activity and socioeconomic status (SES). Nutritional status and body composition characteristics were assessed in terms of body mass index (BMI), upper arm muscle area by height (UAMAH) and percent body fat (PBF) among 276 Tibetan adolescent girls from Kangra district, Himachal Pradesh. Overall, 12.7% of the girls were in the wasting category (using Z-score based classification for UAMAH) and 9.8% were thin. About 16.3% girls were obese. Significant variabilities of PBF have been observed with respect to age and levels of physical activity and wasting. Adolescent girls were observed to have higher lean body mass than body fat.

Abstract

The ratio of index finger to ring finger length (2D:4D) is a sexually dimorphic feature and widely used as an indicator of prenatal androgen-estrogen exposure. Several studies have investigated the relationship between the 2D:4D ratio and the onset of the first menstrual period (menarche) in women.

The present study tested the association patterns between 2D:4D ratio and age at menarche. Furthermore, the impact of methods of measuring finger lengths was considered.

Two samples were used to conduct the study. One sample consisted of 110 women who self-measured their finger lengths. The finger length measurements in the second sample (88 women) were taken from one trained observer using the caliper-based technique. Age at menarche was determined using a retrospective method.

Women from the first sample reported an average age for the onset of the first menstrual bleeding at 12.9 (SD = 1.4) years of age. There was no significant association between the left and right 2D:4D ratio and the age at menarche. The second sample showed a mean age at menarche at 12.8 (SD = 1.3) years of age. Here, the right hand 2D:4D ratio and age at menarche were significantly correlated (p<0.001).

A more feminine 2D:4D ratio was significantly associated with an earlier menarcheal age only in the sample with direct finger length measurements by a trained investigator. The sample using self-measurements yielded no significant associations between menarcheal age and 2D:4D. The use of a reliable and well-founded methodology is essential for obtaining meaningful results.

Abstract

In order to gain an insight into scholars’ concerns emerging from the COVID-19 crisis, we asked scientists from all over the world about their attitudes and predictions regarding the repercussions of this current crisis on academia. Our data showed that the academic world was placed in an unprecedented situation. Results further showed that everybody worked on-line, conducting studies was impossible or highly impeded, and lab work was difficult. Almost a quarter of all scientists participating in our survey were anxious about their scientific employment, and over 25% expected serious financial losses as a consequence of the pandemic. Moreover, we identified sex differences regarding the severity of the COVID-19 impact in the majority of questions. We inferred from this that women perceived to be in a worse situation than men.

Abstract

Biological ageing can be tentatively defined as an intrinsic and inevitable degradation of biological function that accumulates over time at every level of biological organisation from molecules to populations. Senescence is characterised by a progressive loss of physiological integrity, leading to impaired function and increased vulnerability to death. With advancing age, all components of the human body undergo these cumulative, universal, progressive, intrinsic and deleterious (CUPID) changes. Although ageing is not a disease per se, age is the main risk factor for the development of a panoply of age-related diseases. From a mechanistic perspective, a myriad of molecular processes and components of ageing can be studied. Some of them seem especially important and they are referred to as the hallmarks of ageing. There is compelling evidence that senescence has evolved as an emergent metaphenomenon that originates in the difficulty in maintaining homeodynamics in biological systems. From an evolutionary perspective, senescence is the inevitable outcome of an evolutionarily derived equilibrium between the amount of resources devoted to somatic maintenance and the amount of resources devoted to sexual reproduction. Single-target, single-molecule and disease-oriented approaches to ageing are severely limited because they neglect the dynamic, interactive and networking nature of life. These limitations notwithstanding, many authors promote single-target and disease-oriented approaches to senescence, e.g. repurposed drugs, claiming that these methods can enhance human health and longevity. Senescence is neither a disease nor a monolithic process. In this review, the limitations of these methods are discussed. The current state of biogerontology is also summarised.

Abstract

The subject of the research was to assess the level of functional physical fitness of people aged 65 and over, taking into account the sex of the respondents, and to estimate the direction of changes in the functional physical fitness of the respondents as a result of participation in programmed physical activities of a University of the Third Age. The research on the level of functional physical fitness was carried out both among men and women aged 65 and over (104 men – 29% of the respondents and 251 women – 71% of the respondents), in total 355 people who are members of the Universities of the Third Age in Rzeszów, Mielec, Jasło, Zamość, and Seniors’ Clubs in Rzeszów, Stalowa Wola, Przemyśl, Krosno and Lubaczów. The Functional Senior Fitness Test by Rikli and Jones (1999) was used to objectively analyse the level of functional physical fitness in the study group. The individual tests of the Functional Senior Fitness Test give the opportunity to assess the muscle strength of the lower and upper body, flexibility in the upper and lower body areas, agility and dynamic balance as well as the aerobic endurance of the senior citizen.

The research procedure assumed two studies to assess the level of functional physical fitness of people over 65 using the Functional Senior Fitness Test among seniors who are members of Universities of the Third Age participating in physical activities. Study 2 was conducted 6 months after study 1. In order to obtain reliable and credible results of individual tests and to maintain similar conditions for all participants, study 1 was conducted at the University of the Third Age at the beginning of the winter semester, and study 2 at the end of the first half of the academic year. The number of respondents was n = 86.

Men showed statistically significantly higher results in muscle strength in upper and lower parts of the body and aerobic endurance, women in flexibility of upper and lower parts of the body. Regular participation in physical activities among people over 65 has a significant statistical impact on the achievement of higher results in individual motor skills.

Sex significantly differentiates the level of functional physical fitness in selected age groups. A significantly higher level of functional physical fitness was presented by men in the test of muscle strength in in upper and lower parts of the body, agility and dynamic balance, and aerobic endurance, while women showed higher results in flexibility of upper and lower parts of the body.

The analysis of the results of the preliminary (study 1) and repeated (study 2) functional fitness level allows us to find significant differences in the results of the Functional Senior Fitness Test. It is worth noting that the regular participation in programmed physical activities organized at U3A contributed to an improvement in individual motor skills, such as the strength of the lower and upper body and aerobic endurance.

Abstract

The present study attempted to identify sex of an individual using a fingerprint ridge density at three topological areas in the North Indian population. The study population consisted of 134 males and 136 females aged 17 to 25 years (mean age 19.34±2.12). Ridge density (RD) at radial, ulnar and proximal topological areas of the distal phalanges were determined on the surface area of 25mm2. Fingerprint ridge density in a defined area was significantly higher among females as compared to their male counterparts at radial, ulnar and proximal topological areas for both hands. Sexual dimorphic ratio also supported this trend for all three counting areas in right and left hands. Univariate discriminant function analysis explained that the left 2 radial (L2R) (88.1%) had the highest percentage of accuracy for sex identification, followed by the left 3 ulnar (L3U) (82.1%) and the right 2 ulnar (R2U) (81.6%). Multivariate discriminant function analysis showed that the radial topological area of the left hand was the best predictor of sex with the overall accuracy of 84.4%with following discriminant function equation −8.263 − 0.236(L1R) + + 0.321(L2R) + 0.269(L3R) + 0.268(L4R) − 0.067(L5R).

It can be inferred that ridge density in the radial topological area of left hand is the most reliable tool for identifying the sex of an individual.

Abstract

The course of menopause transition (MT) is associated with peculiarities of alterations occurring in a woman’s body, in particular, in the structure of bone tissue. Considering that bones of the paranasal sinuses (BPNSs) play a natural defense role against the spread of dental infection, their structure is important in dentistry. However, no information was found pertaining to changes of BPNSs during MT – a time when dental maladies increase in many women.

The aim of our study was to collate density of BPNSs with status of adrenal steroids in women during MT, since the pattern of their changes determines the course of MT.

Cross-sectional associations were examined between bone density of PNSs assessed by Spiral Computed Tomography and Serum content of testosterone (T), sex hormone binding globulin (SHBG), free androgen index (FAI), insulin, dehydroepiandrosterone sulfate (DHEAS), Adione, and Adiol in 113 women of perimenopausal age (age range from 45 to 55 years) who had already experienced premenopausal menstrual decline (amenorrhea less than 2 years).

Strong positive (r = 0.73) correlation between minimal bone density of maxillary sinus in women with level of DHEAS was detected. It is important to note, that the correlation between minimal density of the lower wall of frontal sinus is a weak positive (0.3). Therefore, it can be suggested that bone tissue of the maxillary sinus is more sensitive to changes in DHEAS.

The study showed that the level of male steroids, in particular DHEAS, affected the state of bone tissue in participants older than 50 years of age.

Abstract

The period of adolescence includes biological, psychological and social maturation. All these processes complement and affect each other. The ultimate goal is the transition from childhood to adulthood which enables individuals to become socialized beings, who are psychologically mature and able to pass on their genetic inheritance. In the process of reaching full maturity, adolescents are exposed to both positive and negative stimuli the socio-cultural environment. In the process of socialization, the influence of peers, and the maturing into social roles is important. At the same time, adolescents mature biologically. A holistic understanding of the sequence of changes that occur during adolescence foregrounds the significance of biology in informing emotions and cognition. Research conducted on adolescents from Wrocław, Poland, showed the impact that physical development plays on social development within a school peer group. Adolescents with a slower pace of maturity, lower BMI, and lower body height achieved the lowest social status in the group’s hierarchy. These adolescents also became victims of peer rejection. The role of scapegoat assigned to them highlighted and completed the symptomatic rejection process, which highlighted negative social group behaviours. In contrast, their peers from the same classes, with higher biological parameters, became leaders in the school’s social groups. Furthermore, sociometric ‘stars’, leaders and gray eminences, compared to scapegoats, achieved maturity faster, and had greater body height and higher BMI among all age groups.