Affine connection representation of gauge fields

There are two ways to unify gravitational field and gauge field. One is to represent gravitational field as principal bundle connection, and the other is to represent gauge field as affine connection. Poincar\'{e} gauge theory and metric-affine gauge theory adopt the first approach. This paper adopts the second. In this approach: (i) Gauge field and gravitational field can both be represented by affine connection; they can be described by a unified spatial frame. (ii) Time can be regarded as the total metric with respect to all dimensions of internal coordinate space and external coordinate space. On-shell can be regarded as gradient direction. Quantum theory can be regarded as a geometric theory of distribution of gradient directions. Hence, gauge theory, gravitational theory, and quantum theory all reflect intrinsic geometric properties of manifold. (iii) Coupling constants, chiral asymmetry, PMNS mixing and CKM mixing arise spontaneously as geometric properties in affine connection representation, so they are not necessary to be regarded as direct postulates in the Lagrangian anymore. (iv) The unification theory of gauge fields that are represented by affine connection can avoid the problem that a proton decays into a lepton in theories such as $SU(5)$. (v) There exists a geometric interpretation to the color confinement of quarks. In the affine connection representation, we can get better interpretations to the above physical properties, therefore, to represent gauge fields by affine connection is probably a necessary step towards the ultimate theory of physics.Comment: 36 page

Necessity for quantum coherence of nondegeneracy in energy flow

In this work, we show that the quantum coherence among non-degenerate energy subspaces (CANES) is essential for the energy flow in any quantum system. CANES satisfies almost all of the requirements as a coherence measure, except that the coherence within degenerate subspaces is explicitly eliminated.We show that the energy of a system becomes frozen if and only if the corresponding CANES vanishes, which is true regardless of the form of interaction with the environment. However, CANES can remain zero even if the entanglement changes over time. Furthermore, we show how the power of energy flow is bounded by the value of CANES. An explicit relation connecting the variation of energy and CANES is also presented. These results allow us to bound the generation of system-environment correlation through the local measurement of the system's energy flow

Effects of Rashba spin-orbit coupling and a magnetic field on a polygonal quantum ring

Using standard quantum network method, we analytically investigate the effect of Rashba spin-orbit coupling (RSOC) and a magnetic field on the spin transport properties of a polygonal quantum ring. Using Landauer-Buttiker formula, we have found that the polarization direction and phase of transmitted electrons can be controlled by both the magnetic field and RSOC. A device to generate a spin-polarized conductance in a polygon with an arbitrary number of sides is discussed. This device would permit precise control of spin and selectively provide spin filtering for either spin up or spin down simply by interchanging the source and drain

Review of Disabled Elderly in China and Tanzania: The Experience and the Challenges

In everywhere there is a sharp increase in population ageing, where the need for amending or creating laws and management that could cover the needs of the disabled elderly in the population. Though, there is no single converging paradigm and countries are experimenting with a number of different approaches.Providing and financing long-term care of the elderly among the most pressing policy issues facing the aging population. A growing population at risk for chronical disability the the very old promises to generate unprecedented right in the demand for long-term care.China demographic change, fueled by declining levels of fertility, which means that China has one of the fastest growing elderly populations in the world. The health of this population segment will have obvious implications for future formal and informal care costs, an issue that is of great concern to Chinese policy makers (Riley, 2004).Tanzania a least developed country located in east Africa is experiencing a rapid aging of elderly where the elderly are living longer. Scholars have suggested that the rapid aging in countries like Tanzania, occurring under premature levels of infrastructure and economic development, may represent extreme challenges for health and social systems to meet the demand for care of aging populations (Frenk, Bobadilla, Stern, Frejka, & Lozano, 1991; Cutler, 2001)A number of studies have illustrated about urban/rural health inequalities among older adults in specific country’s’, though, there is no study that have tried to relate or discuss about two developing country and present the experience and challenges such as in this article aim to illustrate about China and Tanzania. The effort of these two countries is important because there is much to be learned by these two countries in defining the range of policy option and in identifying successful and unsuccessful practices. The review of Tanzania is based on the data in the of HBS 2007 and the review of China is based on National Bureau of Statistics.The advantages and shortcomings of the two systems were analyzed with recommendations for future developments. Such comparisons across nations can inform social policy debates in China and Tanzania as to how to prepare for population aging. The originality of such comparison can shed light on issues for LTC service development in other countries especially the emerging economy ones. Keywords: Elderly Disability, Developing countries, Long term-care and China and Tanzani

Two Adjacent Phenylalanines In the NMDA Receptor GluN2A Subunit M3 Domain Interactively Regulate Alcohol Sensitivity and Ion Channel Gating

The N-methyl-d-aspartate (NMDA) receptor is a key target of ethanol action in the central nervous system. Alcohol inhibition of NMDA receptor function involves small clusters of residues in the third and fourth membrane-associated (M) domains. Previous results from this laboratory have shown that two adjacent positions in the M3 domain, F636 and F637, can powerfully regulate alcohol sensitivity and ion channel gating. In this study, we report that these positions interact with one another in the regulation of both NMDA receptor gating and alcohol action. Using dual mutant cycle analysis, we detected interactions among various substitution mutants at these positions with respect to regulation of glutamate EC50, steady-state to peak current ratios (Iss:Ip), mean open time, and ethanol IC50. This interaction apparently involves a balancing of forces on the M3 helix, such that the disruption of function due to a substitution at one position can be reversed by a similar substitution at the other position. For example, tryptophan substitution at F636 or F637 increased or decreased channel mean open time, respectively, but tryptophan substitution at both positions did not alter open time. Interestingly, the effects of a number of mutations on receptor kinetics and ethanol sensitivity appeared to depend upon subtle structural differences, such as those between the isomeric amino acids leucine and isoleucine, as they could not be explained on the basis of sidechain molecular volume or hydrophilicity

Gait recognition using normalized shadows

WOS:000426986000189 (Nº de Acesso Web of Science)Surveillance of public spaces is often conducted with the help of cameras placed at elevated positions. Recently, drones with high resolution cameras have made it possible to perform overhead surveillance of critical spaces. However, images obtained in these conditions may not contain enough body features to allow conventional biometric recognition. This paper introduces a novel gait recognition system which uses the shadows cast by users, when available. It includes two main contributions: (i) a method for shadow segmentation, which analyzes the orientation of the silhouette contour to identify the feet position along time, in order to separate the body and shadow silhouettes connected at such positions; (ii) a method that normalizes the segmented shadow silhouettes, by applying a transformation derived from optimizing the low rank textures of a gait texture image, to compensate for changes in view and shadow orientation. The normalized shadow silhouettes can then undergo a gait recognition algorithm, which in this paper relies on the computation of a gait energy image, combined with linear discriminant analysis for user recognition. The proposed system outperforms the available state-of-the-art, being robust to changes in acquisition viewpoints.info:eu-repo/semantics/acceptedVersio

China : a rich flora needed of urgent conservation

China is one of the richest countries in plant biodiversity in the world. Besides to a rich flora, which contains about 33.000 vascular plants (being 30.000 of these angiosperms, 250 gymnosperms, and 2.600 pteridophytes), there is a extraordinary ecosystem diversity. In addition, China also contains a large pool of both wild and cultivated germplasm; one of the eight original centers of crop plants in the world was located there. China is also considered one of the main centers of origin and diversification for seed plants on Earth, and it is specially profuse in phylogenetically primitive taxa and/or paleoendemics due to the glaciation refuge role played by this area in the Quaternary. The collision of Indian subcontinent enriched significantly the Chinese flora and produced the formation of many neoendemisms. However, the distribution of the flora is uneven, and some local floristic hotspots can be found across China, such as Yunnan, Sichuan and Taiwan. Unfortunately, threats to this biodiversity are huge and have increased substantially in the last 50 years. The combined effects of habitat destruction and/or fragmentation, environmental contamination, overexploitation of natural resources and, in lower extent, introduction of exotic species, have produced an irremediable damage to plant biodiversity; furthermore, the economic and population growth have contributed to this deterioration. Currently it is considered that up to 5.000 species of flora are endangered in China, and some taxa have already become extinct. Although government authorities have done some efforts in order to preserve biodiversity in recent years, there is still a lot of work to do. China has established a extense network of nature reserves and protected areas, covering more than 16% of the total land area; nevertheless, lack of budget and staff are common trends in their management. Ex situ conservation is still also deficient, primarily due to botanical gardens are not representative of the several local floras and they often have not adequate sizes and amount of species. The lack of an efficient environmental legislation and education are also root causes which enhance the loss of Chinese plant biodiversity