Existence of Positive Solutions for m-Point Boundary Value Problem for Nonlinear Fractional Differential Equation

We investigate an m-point boundary value problem for nonlinear fractional differential equations. The associated Green function for the boundary value problem is given at first, and some useful properties of the Green function are obtained. By using the fixed point theorems of cone expansion and compression of norm type and Leggett-Williams fixed point theorem, the existence of multiple positive solutions is obtained

Effect of Cathodic Polarization of n-TiO_2 Thin Films on Their Photoresponse towards Water Splitting Reactions

Cathodic reduction of Titanium oxide (n-TiO_2) thin films was investigated as an alternative approach to customary hydrogen modification of n-TiO_2 under hydrogen gas stream at high temperature. Hydrogen modification of n-TiO_2 was carried out electrochemically under cathodic polarization. The photo-response of the electrochemically hydrogen modified n-TiO_2 (HM-n-TiO_2) exhibited a four-fold enhancement in their photoresponse compared to n-TiO_2 during water splitting under solar simulated light. The photoactivity of HM-n-TiO_2 suffers a substantial decrease after heat-treatment at 200°C, remarkably the photoactivity of these samples was fully repaired after re-hydrogenation under similar conditions. The electrodes were characterized using electrochemical and spectroscopic techniques

Derivative-order-dependent stability and transient behaviour in a predator–prey system of fractional differential equations

In this paper, the static and dynamic behaviour of a fractional-order predator–prey model are studied, where the nonlinear interactions between the two species lead to multiple stable states. As has been found in many previous systems, the stability of such states can be dependent on the fractional order of the time derivative, which is included as a phenomenological model of memory-effects in the predator and prey species. However, what is less well understood is the transient behaviour and dependence of the observed domains of attraction for each stable state on the order of the fractional time derivative. These dependencies are investigated using analytical (for the stability of equilibria) and numerical (for the observed domains of attraction) techniques. Results reveal far richer dynamics compared to the integer-order model. We conclude that, as well as the species and controllable parameters, the memory effect of the species will play a role in the observed behaviour of the system

Epigenetic Influences of Mobile Genetic Elements on Ciliate Genome Architecture and Evolution

Mobile genetic elements (MGEs) are transient genetic material that can move either within a single organism\u27s genome or between individuals or species. While historically considered “junk” DNA (i.e., deleterious or at best neutral), more recent studies reveal the potential adaptive advantages MGEs provide in lineages across the tree of life. Ciliates, a group of single-celled microbial eukaryotes characterized by nuclear dimorphism, exemplify how epigenetic influences from MGEs shape genome architecture and patterns of molecular evolution. Ciliate nuclear dimorphism may have evolved as a response to transposon invasion and ciliates have since co-opted transposons to carry out programmed DNA deletion. Another example of the effect of MGEs is in providing mechanisms for lateral gene transfer (LGT) from bacteria, which introduces genetic diversity and, in several cases, may drive ecological specialization in ciliates. As a third example, the integration of viral DNA, likely through transduction, provides new genetic materials and can change the way host cells defend themselves against other viral pathogens. We argue that the acquisition of MGEs through non-Mendelian patterns of inheritance, coupled with their effects on ciliate genome architecture and persistence throughout evolutionary history, exemplify how the transmission of mobile elements should be considered a mechanism of transgenerational epigenetic inheritance

Evaluating 5-nitrothiazoles as trypanocidal agents

OA Monitor ExerciseOA Monitor ExerciseThe growth inhibitory properties of a 5-nitrothiazole series was evaluated against Trypanosoma brucei. A subset of related compounds displayed the greatest potency towards the parasite while exhibiting little cytotoxic effect on mammalian cells, with this anti-parasitic activity being dependent on expression of a type I nitroreductase by the trypanosome. We conclude that the 5-nitrothiazole class of nitroheterocycle may represent new leads in the treatment of human African trypanosomiasis.BAV acknowledges financial support by FONDECYT Postdoctorado 313036

Skin Biophysical Characteristics in Patients with Keratoconus: A Controlled Study

Background. Keratoconus is a relatively common corneal disease causing significant visual disability. Individuals with connective tissue disorders that affect the skin such as Marfan’s syndrome and Ehlers-Danlos syndrome or patients with atopic dermatitis show an increased prevalence of keratoconus. It seems that there are some concurrent alterations of skin and cornea in patients with keratoconus. Objective. We plan to compare skin biophysical characteristics in patients with keratoconus and healthy controls. Methods. Forty patients with keratoconus (18 females and 22 males) with mean (SD) age of 33.32 (9.55) years (range 19–56) and 40 healthy controls were recruited to this study. Skin biophysical characteristics including cutaneous resonance running time (CRRT), stratum corneum hydration, and melanin values were measured in patients and controls. Results. The median CRRT, stratum corneum hydration, and melanin measurements were significantly lower in patients with keratoconus in comparison with healthy controls. Conclusion. There are some alterations of skin biophysical properties in patients with keratoconus. Therefore, the assessment of these skin parameters could provide us some clues to the possible common biophysical variations of cornea and skin tissue in diseases such as keratoconus