There are more than one million microbial cells in every drop of seawater, and their collective metabolisms not only recycle nutrients that can then be used by larger organisms but also catalyze key chemical transformations that maintain Earth's habitability. Understanding how these microbes interact with each other and with multicellular hosts is critical to reliably quantify any functional as...

Conformal Killing vectors (CKVs) preserve the spacetime metric up to a factor. Homothetic vectors and Killing vectors are special cases of CKVs. Classification of some classes of spacetimes on the basis of CKVs give interesting results showing how homothetic and Killing vectors which form subsets of the set of CKVs can be recovered as a result of the above classification. ∗On leave from: Centre...

Lie derivatives of various geometrical and physical quantities define symmetries and conformal symmetries in general relativity. Thus we obtain motions, collineations, conformal motions and conformal collineations. These symmetries are used not only to find new solutions of Einstein’s field equations but to classify the spaces also. Different classification schemes are presented here. Relations...

Mehdi Eshagh 1, Matloob Hussain 1,2, Robert Tenzer 3,4,* and Mohsen Romeshkani 5 1 Department of Engineering Science, University West, Trollhättan 46186, Sweden; [email protected] (M.E.); [email protected] (M.H.) 2 Department of Earth Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan 3 The Key Laboratory of Geospace Environment and Geodesy, Wuhan University, Wuhan 430079, China ...

SIMD computers are a class of massively parallel computer in which many processors simultaneously execute the same instructions on their own data. This paper briefly reviews the history of the development of SIMD computers, and gives an overview of the state of the art in SIMD computers by comparing the origins, hardware, software, performance, price and marketing of three commercially availabl...

Although the matrix element of the gluon spin operator in nucleon helicity states is known to be independent of some special choices of gauge, we show that it is not invariant under a general gauge transformation. We find that there exists a simple means of obtaining the matrix element in a different choice of gauge from a calculation made in one specific gauge. Similar conclusions hold for oth...

1 Department of Zoology,University of Sargodha,Sargodha, Pakistan 2 Department of Biosciences, COMSATS Institute of Information Technology (CIIT), Park Road, Chakh Shazad, Islamabad, Pakistan 3 Department of Botany,PMAS Arid Agriculture University, Rawalpindi, Pakistan 4 Department of Remote Sensing and GIS, PMAS Arid Agriculture University, Rawalpindi, Pakistan 5 Department of Zoology, PMASAri...

The unintentional injuries due to falls in elderly people give rise to a multitude of health and economic problems due to the growing aging population. The use of early pre-impact fall alarm and self-protective control could greatly reduce fall injuries. This paper aimed to explore and implement a pre-impact fall recognition/alarm method for free-direction fall activities based on understandi...

introduction the khoshk river is originated from golestan and ghalat highlands and flow in a northwest and southeast direction. after traversing a short distance it covers golestan and dukohak from the right and the ghasr ghomshe tributary from the left. then, in a direct cross from the middle of shiraz metro police, it will divide it into half in south and east and at the end it will pour into...