Breathe easy: microbes protect from allergies

Changes in gut microbial composition have been linked to inflammatory bowel disease, obesity and allergies in humans. A new study shows that pattern recognition of commensal bacteria by B cells reduces allergic inflammation in mice, adding to the mounting evidence for the 'hygiene hypothesis' (pages 538–546)

Disruption of the gut microbiome as a risk factor for microbial infections

The discovery that microorganisms can be etiologic agents of disease has driven clinical, research and public health efforts to reduce exposure to bacteria. However, despite extensive campaigns to eradicate pathogens (via antibiotics, vaccinations, hygiene, sanitation, etc.), the incidence and/or severity of multiple immune-mediated diseases including, paradoxically, infectious disease have increased in recent decades. We now appreciate that most microbes in our environment are not pathogenic, and that many human-associated bacteria are symbiotic or beneficial. Notably, recent examples have emerged revealing that the microbiome augments immune system function. This review will focus on how commensal-derived signals enhance various aspects of the host response against pathogens. We suggest that modern lifestyle advances may be depleting specific microbes that enhance immunity against pathogens. Validation of the notion that absence of beneficial microbes is a risk factor for infectious disease may have broad implications for future medical practices

MULTI-DIMENSIONAL COSMOLOGY AND DSR–GUP

A multi-dimensional cosmology with FRW type metric having four-dimensional spacetime and d-dimensional Ricci-flat internal space is considered with a higher-dimensional cosmological constant. The classical cosmology in commutative and Doubly Special Relativity–Generalized Uncertainty Principle (DSR–GUP) contexts is studied and the corresponding exact solutions for negative and positive cosmological constants are obtained. In the positive cosmological constant case, it is shown that unlike the commutative as well as GUP cases, in DSR–GUP case both scale factors of internal and external spaces after accelerating phase will inevitably experience decelerating phase leading simultaneously to a big crunch. This demarcation from GUP originates from the difference between the GUP and DSR–GUP algebras. The important result is that unlike GUP which results in eternal acceleration, DSR–GUP at first generates acceleration but prevents the eternal acceleration at late-times and turns it into deceleration

Semileptonic Dq→K1ℓνD_{q}\to K_{1}\ell \nu and nonleptonic D→K1πD\to K_1 \pi decays in three--point QCD sum rules and factorization approach

We analyze the semileptonic $D_{q}\to K_1 \ell\nu$ transition with $q=u, d, s$, in the framework of the three--point QCD sum rules and the nonleptonic $D\to K_1 \pi$ decay within the QCD factorization approach. We study $D_{q}$ to $K_1(1270)$ and $K_1(1400)$ transition form factors by separating the mixture of the $K_1(1270)$ and $K_1(1400)$ states. Using the transition form factors of the $D\to K_1$, we analyze the nonleptonic $D\to K_1 \pi$ decay. We also present the decay amplitude and decay width of these decays in terms of the transition form factors. The branching ratios of these channel modes are also calculated at different values of the mixing angle $\theta_{K_1}$ and compared with the existing experimental data for the nonleptonic case.Comment: 28 Pages, 20 Figures and 9 Table

Multi-Dimensional Cosmology and GUP

We consider a multidimensional cosmological model with FRW type metric having 4-dimensional space-time and $d$-dimensional Ricci-flat internal space sectors with a higher dimensional cosmological constant. We study the classical cosmology in commutative and GUP cases and obtain the corresponding exact solutions for negative and positive cosmological constants. It is shown that for negative cosmological constant, the commutative and GUP cases result in finite size universes with smaller size and longer ages, and larger size and shorter age, respectively. For positive cosmological constant, the commutative and GUP cases result in infinite size universes having late time accelerating behavior in good agreement with current observations. The accelerating phase starts in the GUP case sooner than the commutative case. In both commutative and GUP cases, and for both negative and positive cosmological constants, the internal space is stabilized to the sub-Planck size, at least within the present age of the universe. Then, we study the quantum cosmology by deriving the Wheeler-DeWitt equation, and obtain the exact solutions in the commutative case and the perturbative solutions in GUP case, to first order in the GUP small parameter, for both negative and positive cosmological constants. It is shown that good correspondence exists between the classical and quantum solutions.Comment: 21 pages, 15 figures, minor revision, references adde

RiPPLE: A crowdsourced adaptive platform for recommendation of learning activities

© 2019, UTS ePRESS. All rights reserved. This paper presents a platform called RiPPLE (Recommendation in Personalised Peer-Learning Environments) that recommends personalized learning activities to students based on their knowledge state from a pool of crowdsourced learning activities that are generated by educators and the students themselves. RiPPLE integrates insights from crowdsourcing, learning sciences, and adaptive learning, aiming to narrow the gap between these large bodies of research while providing a practical platform-based implementation that instructors can easily use in their courses. This paper provides a design overview of RiPPLE, which can be employed as a standalone tool or embedded into any learning management system (LMS) or online platform that supports the Learning Tools Interoperability (LTI) standard. The platform has been evaluated based on a pilot in an introductory course with 453 students at The University of Queensland. Initial results suggest that the use of the RiPPLE platform led to measurable learning gains and that students perceived the platform as beneficially supporting their learning

Spectral, dyeing and antimicrobial properties of some monoazo naphthalimide dyes on polyamide

A series of monoazo disperse dyes based on naphthalimide has been applied on to the nylon fabrics. The build-up values and dyeing properties of these dyes, such as leveling, and wash, light and rub fastnesses on nylon fabrics have been assessed. The dyes N-2-aminomethylpyridine-1,8-naphthalimide- azo-4″-N,N-diethyl meta toluidine (A) and N-2-aminomethylpyridine-1,8-naphthalimide-azo-2″- acetylamino-4″- N,N- diethyl aniline (B) show higher build-up values on polyamide fabrics as compared to the dyes N-2-aminomethylpyridine-1,8-naphthalimide- azo- 4″- N-hydroxy ethyl-N- ethyl aniline (C) and N-2-aminomethylpyridine-1,8-naphthalimide- azo- 4″- N-hydroxy ethyl-N- ethyl aniline quaternized with 1- bromobutane (D). All of the applied dyes exhibit excellent rub fastness, good wash fastness and moderate light fastness on nylon fabrics. In addition, the molar extinction coefficient, wavelengths of the maximum absorption and solvatochromism effects have also been studied using chloroform, toluene, and DMF as solvents. Positive solvatochromism occurs when toluene is replaced by DMF as solvent. The antimicrobial properties of dyed fabrics are evaluated against various bacteria; the dyed fabrics exhibit antimicrobial efficacy against both Gram-positive and Gram-negative bacteria.

Application of Poly(hydroxyalkanoate) In Food Packaging: Improvements by Nanotechnology

The environmental impact of plastic usage is of critical concern and too great to repair. A shift toward biodegradable food packaging is one option. The aim of this review paper is the study of the potential of biodegradable materials for food packaging. The main characteristics in relation to food usage can be narrowed down to mass transfer (gas and water vapor), thermal and mechanical properties. Among several kinds of biodegradable polymers, poly(hydroxyalkanoate) is one of the favorable candidates for food packaging due to its physical and mechanical properties, biodegradability, with low permeability for O2, H2O and CO2 without residues of catalysts and water solubility. The main focus of this article is to address poly(hydroxyalkanoate) as a potential candidate for food packaging. The need of applying biobased polymers in food packaging is presented in the introduction of this study. We also describe the most common biopolymers providing a brief overview of classification and application. This is followed by an outline of biopolymer production and a main section in which the properties of poly(hydroxybutyrate)-based nanocomposites of greatest relevance to food packaging are discussed. Furthermore, several approaches for improvement of poly(hydroxybutyrate) properties are described and the role of nanotechnology to improve its mechanical properties is presented. Finally, the article concludes with a summary as well as some possible future trends