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In this paper, we prove several conjectures raised by Zhi-Wei Sun on determinants and permanents by the eigenvectors-eigenvalues identity recently highlighted by Denton, Parke, Tao and Zhang. [ABSTRACT FROM AUTHOR]

In this paper, we study certain determinants involving tangent functions. We prove that for any odd number n ⩾ 3 and s ∈ Z + , the determinant D (n , s) = det (tan s ⁡ π j + k n) 1 ⩽ j , k ⩽ n − 1 ∈ n n − 2 Z . In the special case s = 2, we confirm a conjecture raised by Zhi-Wei Sun in 2019. [ABSTRACT FROM AUTHOR]

In recent years, developing artificial cells of higher complexity has emerged as being key to simulating advanced life behaviors, among which coacervate microdroplets are a promising kind of model artificial cell. Constructing simple coacervate systems in vitro which can subsequently achieve specific responses to environmental stimuli to form coacervate microdroplet communities are fundamental for studying the interactions between liquid–liquid phase separated molecules and the way such interactions determine material properties, composition and phase behavior. Herein, we propose a membrane-free artificial cell based on recombinant spidroin, NT2RepCT, which utilizes the complex structure of spidroin to provide coacervate microdroplets with a unique population morphology in response to environmental stimuli. By changing the environmental conditions such as protein concentration, pH and temperature, the coacervate microdroplets of single-type, regular adhesion-type and irregular adhesion-type were statistically generalized, and it is highlighted that the adhesion-type of coacervate microdroplets depended on the α-helical percentage, complex folding degree of spidroin and internally hydrophobic environment of the coacervate, while it was inversely proportional to the surface hydrophobic environment. Much more interesting, regulation of the non-enzymatic polymerization reaction of oligonucleotides was successfully achieved by adjusting the population morphology of coacervate microdroplets. [ABSTRACT FROM AUTHOR]

We presented an unreported T96R mutation induced transthyretin cardiac amyloidosis (ATTR). The biochemical and biophysical properties were explored to support its pathogenicity. Understanding the biochemical and biophysical nature of genetically mutated transthyretin (TTR) proteins is key to provide precise medical cares for ATTR patients. Genetic testing showed heterozygosity for the T96R pathogenic variant c.347C > G (ATTR p.T116R) after myocardial biopsy confirmed amyloid deposition. Biochemical characterizations revealed slight perturbation of its thermodynamic stability (Cm=3.7 M for T96R, 3.4 M for WT and 2.3 M for L55P (commonly studied TTR mutant)) and kinetic stability (t1/2=39.8 h for T96R, 42 h for WT and 4.4 h in L55P). Crosslinking experiment demonstrated heterozygous subunit exchange between wild-type and TTR T96R protein destabilized the tetramer. Inhibitory effect of tafamidis and diflunisal on TTR T96R fibril formation was slightly less effective compared to WT and L55P. A novel T96R mutation was identified for TTR protein. Biochemical and biophysical analyses revealed slightly destabilized kinetic stability. T96R mutation destabilized heterozygous protein but not proteolytic degradation, explaining its pathogenicity. Inhibitory effect of small molecule drugs on T96R mutation was different, suggesting personalized treatment may be required. [ABSTRACT FROM AUTHOR]

Cell surface engineering is an effective strategy to improve the tolerance of living cells against harsh environments as well as endow cells with various properties and functionalities, which they do not possess inherently. However, the research emphasis on single-cell surface engineering with the emergence of collective functionality is still rare. In this study, we encapsulate a single living cell with TiO2 nanoparticles (Degussa P25, composed of anatase and rutile crystallites) and conductive polymer polypyrrole (PPy). The driving force generated from the nanoparticles TiO2 and PPy could be utilized to manipulate cells that are more than a hundred times their own body size. Different collective behaviors of unicellular organisms can be achieved under various conditions. Especially, the engineered cells could be endowed with a swarming negative phototaxis migration under UV light in the presence of ferrocene methanol (MFc). Given that the collective behaviors of organismic swarms can greatly improve the adaptability and survivability compared to individual ones, we thus anticipate that such a studied technique could open up opportunities for the manipulation of the collective behaviors of unicellular organisms and have great potential in cell therapy as well as biosensors. [ABSTRACT FROM AUTHOR]

(1) Background: The benefits of weight management are widely recognized, and prolonged fasting duration has become a common method for weight control. The suitability of time-restricted eating (TRE) for elderly individuals remains controversial. This study aims to examine the correlation between fasting duration and mortality within a nationally representative cohort of elderly individuals in the United States. (2) Methods: Data were extracted from a prospective cohort study conducted as part of the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018. Participants aged over 60 with complete data on dietary intake and mortality follow-up information were included. Fasting duration was assessed using two 24 h dietary recalls. All the participants were categorized into fasting duration quartiles. Mortality outcomes were ascertained through the National Death Index. Cox proportional hazards regression models were utilized to analyze the association between fasting duration and mortality. (3) Results: The final analysis included 10,561 elderly participants (mean age 69.89, 45.58% male). Individuals with the longest fasting duration (over 12.38 h) had a significantly higher risk of CVD mortality compared to those with a normal fasting duration (10.58-12.38 h). This elevated CVD mortality risk was particularly pronounced in males, individuals over 70 years old, and non-shift workers. A non-linear relationship was observed between fasting duration and all-cause mortality and CVD mortality. (4) Conclusions: Prolonged fasting periods are associated with a higher risk of CVD mortality in the elderly population, although this correlation is not evident for all-cause, cancer, or other-cause mortality. A fasting duration of 11.49 h correlates with the lowest mortality risk. Additionally, elderly individuals with the shortest fasting duration exhibit elevated hazard ratios for both cancer and other-cause mortality. As with any health intervention, clinicians should exercise caution when recommending a fasting regimen that is personalized to the health condition of people who are older. Further research through randomized controlled trials should be conducted to comprehensively investigate the impact of TRE on mortality.