Nonextensive statistical mechanics applied to protein folding problem: kinetics aspects

A reduced (stereo-chemical) model is employed to study kinetic aspects of globular protein folding process, by Monte Carlo simulation. Nonextensive statistical approach is used: transition probability p i j between configurations i &#8594; j is given by p i j =[1 +(1 - q)&#916;Gi j/kB T ]1/(1-q), where q is the nonextensive (Tsallis) parameter. The system model consists of a chain of 27 beads immerse in its solvent; the beads represent the sequence of amino acids along the chain by means of a 10-letter stereo-chemical alphabet; a syntax (rule) to design the amino acid sequence for any given 3D structure is embedded in the model. The study focuses mainly kinetic aspects of the folding problem related with the protein folding time, represented in this work by the concept of first passage time (FPT). Many distinct proteins, whose native structures are represented here by compact self avoiding (CSA) configurations, were employed in our analysis, although our results are presented exclusively for one representative protein, for which a rich statistics was achieved. Our results reveal that there is a specific combinations of value for the nonextensive parameter q and temperature T, which gives the smallest estimated folding characteristic time (t). Additionally, for q = 1.1, (t) stays almost invariable in the range 0.9 < T < 1.3, slightly oscillating about its average value <img border=0 width=32 height=32 src="../../../../../../../img/revistas/bjp/v39n2a/a16txt01.gif" align=absmiddle > or = 27 ±&#963;, where &#963; = 2 is the standard deviation. This behavior is explained by comparing the distribution of the folding times for the Boltzmann statistics (q &#8594; 1), with respect to the nonextensive statistics for q = 1.1, which shows that the effect of the nonextensive parameter q is to cut off the larger folding times present in the original (q &#8594; 1) distribution. The distribution of natural logarithm of the folding times for Boltzmann statistics is a triple peaked Gaussian, while, for q = 1.1 (Tsallis), it is a double peaked Gaussian, suggesting that a log-normal process with two characteristic times replaced the original process with three characteristic times. Finally we comment on the physical meaning of the present results, as well its significance in the near future works

The effect of local thermal fluctuations on the folding kinetics: a study from the perspective of the nonextensive statistical mechanics

Protein folding is a universal process, very fast and accurate, which works consistently (as it should be) in a wide range of physiological conditions. The present work is based on three premises, namely: ($i$) folding reaction is a process with two consecutive and independent stages, namely the search mechanism and the overall productive stabilization; ($ii$) the folding kinetics results from a mechanism as fast as can be; and ($iii$) at nanoscale dimensions, local thermal fluctuations may have important role on the folding kinetics. Here the first stage of folding process (search mechanism) is focused exclusively. The effects and consequences of local thermal fluctuations on the configurational kinetics, treated here in the context of non extensive statistical mechanics, is analyzed in detail through the dependence of the characteristic time of folding ($\tau$) on the temperature $T$ and on the nonextensive parameter $q$.The model used consists of effective residues forming a chain of 27 beads, which occupy different sites of a $3-$D infinite lattice, representing a single protein chain in solution. The configurational evolution, treated by Monte Carlo simulation, is driven mainly by the change in free energy of transfer between consecutive configurations. ...Comment: 19 pages, 3 figures, 1 tabl

Awareness and Behaviors Regarding COVID-19 among Albanian Undergraduates

The coronavirus disease 2019 (COVID-19) pandemic has led to the adoption of restriction measures that have had notable consequences on the health and wellbeing of individuals. This survey was carried out on a sample of 905 Albanian undergraduates to assess their knowledge about COVID-19 and their health-related behaviors and communication changes during lockdown. The students were invited to complete a pre-validated questionnaire during lessons. The results show that the majority of the surveyed students were able to answer correctly about the main epidemiological features of the disease. The level of knowledge was proven to be proportional to the students' education level (enrollment year and age). No considerable relationship emerged with respect to diet or smoking. On the other hand, a relevant portion of the sample (37.6%) declared decreased physical activity (PA). Finally, a notable increase in the intensity and frequency of communication with their peers and with their parents was declared by 34.7% and 50.8% of the sample, respectively. Lifestyle variables were found to be mutually related, as were communication outcomes. The participants showed a satisfactory awareness regarding the COVID-19 epidemic. However, the registered reduction in PA may represent a public health issue and should be addressed with adequate policies. The use of electronic media seems to have increased communication habits in this population group

Capturing the Features of Physical Activity in Old Adults during the COVID-19 Pandemic: Results of an Italian Survey

The restriction measures adopted to control the COVID-19 pandemic had significant consequences on individuals’ lifestyles. This study is aimed at assessing the amount and type of habitual physical activity (PA) in older adults during the advanced phase of the pandemic and their possible relationships with sociodemographic aspects. A questionnaire that included sociodemographic characteristics and the Physical Activity Scale for the Elderly (PASE) was administered online to elderly subjects living in the Apulia region, South Italy. A sample of 939 participants (57.1% F; mean age 75.9 ± 6.3) was obtained. In total, 68.8% of female respondents reported a decrease in PA during the pandemic, while 55.1% of men maintained their previous levels (&lt;0.001). The total PASE score did not differ between gender groups (median value 91.7 in males vs. 90.0 in females; p = 0.067). However, differences were registered in leisure activities, particularly regarding walking (23.8 ± 14.8 in males vs. 20.2 ± 14.6 in females; p = 0.001). Higher PA levels were related with lower age (OR 0.253; 95% CI 0.192–0.333; p = 0.001). Since inactivity can affect elderly health and wellbeing, and considering the impact of the COVID-19 lockdown on this habit, health promotion strategies to counteract the negative effects of the pandemic should include interventions aimed at increasing PA in this sub-group of the population, especially among women and elderly subjects

Climate Changes, Natural Resources Depletion, COVID-19 Pandemic, and Russian-Ukrainian War: What Is the Impact on Habits Change and Mental Health?

Climate Change, Natural Resources Depletion, COVID-19, and Wars are some of the great challenges of our time. The consequences will affect psychological well-being and could have a harmful impact on mental health. This study aimed to assess the level of preoccupation and fears surrounding issues of the 21st-century and the implication for psychological well-being of the general population from Central/Southern Italy among different age groups. A questionnaire that included sociodemographic characteristics, topics formulated ad-hoc about preoccupation, fears, habits, and willingness to change habits in the future related to the 21st-century challenges, and the Depression Anxiety Stress Scales 21 (DASS-21) was administered online. A sample of 1831 participants (61% F; mean age 47.71 ± 17.30) was obtained. Results showed that young adults and older adults, respectively, reported greater and less psychological well-being. Young adults reported higher scores for preoccupation, changing habits, and willingness to change habits in the future, while older adults reported the lowest scores except for changing habits, also controlling for gender. Results for this variable, as well as correlations between the many variables described, rely on the specificity of age, and 21st-century challenges. Moreover, the main fears related to the 21st-century concerns were different based on both age and gender. In conclusion, the various stresses of the 21st-century discussed in this study have a relationship with personal well-being, and it is important to consider potential global mental health issues resulting from these stressors

Knowledge and lifestyle behaviors related to covid-19 pandemic in people over 65 years old from southern Italy

Background: Control measures adopted during the COVID-19 pandemic had a considerable impact on human daily life and lifestyles. Adherence to the recommended measures is influenced by knowledge and attitudes towards the disease. This cross-sectional study aimed to assess the level of knowledge regarding COVID-19, the related control measures, and lifestyle behaviors adopted during the pandemic in a sample of elderly Italian people. Methods: A web-based questionnaire investigating socio-demographic characteristics, knowledge of COVID-19, the related preventive measures, and lifestyle changes that occurred during the pandemic, were distributed to ≥65 years old people living in South Italy. Results: A satisfactory level of knowledge about COVID-19 and the related control measures has been found in the enrolled sample. However, a decrease in physical activity, as well as worsening sleeping and dietary habits, were found in roughly 60% of participants. Females were impacted greater by these lifestyle changes. Conclusions: Participants in this study showed a good level of knowledge regarding COVID-19 and its prevention. Nevertheless, they reported an increase in unhealthy habits that may have important health consequences in the long term and should be addressed by public health interventions targeted at older people

Acceptance of covid-19 vaccination in the elderly: A cross-sectional study in Southern Italy

In Italy, at the end of 2020, a voluntary immunization plan against COVID-19 was in-troduced, involving elderly among the first target categories. The aim of this study was to assess, through an online questionnaire, the acceptance of COVID-19 vaccination in a sample of older adults from southern Italy. Of a total of 1041 respondents (41.7% males, mean age 76.6 ± 6.5), 965 (92.7%) were vaccinated or willing to be vaccinated against COVID-19, although less than half of the sample was favorable to vaccinations and agreed with mandatory immunization. Acceptance of COVID-19 vaccination was found to be positively related with higher educational level (OR = 1.875, CI95% = 1.113–3.161; p = 0.018) and having social/mass media as a main source of information (OR = 2.415 CI95% = 1.358–4.296, p = 0.003). On the contrary, an inverse relationship was found between acceptance of COVID-19 vaccination and having fulfilled the questionnaire after the intro-duction of green pass (OR = 0.218, CI95% = 0.129–0.369; p &lt; 0.001). Therefore, although this evidence needs to be further confirmed, it is possible to agree with previous studies reporting that compulsory measures, such as green pass implementation, must be accompanied by effective education and information strategies of the target population

Knowledge and acceptance of COVID-19 vaccination among undergraduate students from central and southern Italy

At the end of 2020, the Italian Ministry of Health launched a national vaccination campaign to counteract the COVID-19 pandemic. The present study aimed at appraising levels of knowledge about and acceptance of COVID-19 vaccination in a sample of Italian undergraduates during the first phase of the immunization plan. A web-based questionnaire was administered to students attending universities in Bari, Naples, and Rome during the period February–April 2021. Of the total of 3226 participants, 91.9% were keen to receive a COVID-19 vaccination. More than 80% gave correct answers to questions about COVID-19 vaccine administration, functioning, and effects on community health. However, only 63.8% identified the correct composition of the available vaccines. Knowledge was found to be related to sociodemographic features and COVID-19 vaccination acceptance (p &lt; 0.05). COVID-19 vaccination acceptance was found to be related to having a previous vaccination against influenza (OR 3.806, CI 95% 1.181–12.267; p = 0.025) and knowledge (OR 4.759, CI 95% 2.106– 10.753; p = 0.000). These results show a good level of awareness about COVID-19 vaccination in this population, which may indicate the effectiveness of communication strategies accompanying the COVID-19 immunization campaign in Italy