Clinical features of pneumonia in extreme old age

The clinical features of 70 people over the age of 85 with radiologically positive pneumonia were studied. It was shown that the classical presenting symptoms of pneumonia were often absent and 81 % had one or more acute ’geriatric’ features such as acute confusion, recent onset of falls, recent worsening immobility or recent onset of incontinence, at the time of presentation. An increased risk of mortality was associated with acute confusion, dementia, central cyanosis and long term immobility. Well kept body temperature and respiratory rate charts provide a useful early warning of possible pneumonia in very elderly in patients and the finding of a raised body temperature with a raised respiratory rate should always prompt the need to rule out lower respiratory tract infection.peer-reviewe

Designing Optimal Quantum Detectors Via Semidefinite Programming

We consider the problem of designing an optimal quantum detector to minimize the probability of a detection error when distinguishing between a collection of quantum states, represented by a set of density operators. We show that the design of the optimal detector can be formulated as a semidefinite programming problem. Based on this formulation, we derive a set of necessary and sufficient conditions for an optimal quantum measurement. We then show that the optimal measurement can be found by solving a standard (convex) semidefinite program followed by the solution of a set of linear equations or, at worst, a standard linear programming problem. By exploiting the many well-known algorithms for solving semidefinite programs, which are guaranteed to converge to the global optimum, the optimal measurement can be computed very efficiently in polynomial time. Using the semidefinite programming formulation, we also show that the rank of each optimal measurement operator is no larger than the rank of the corresponding density operator. In particular, if the quantum state ensemble is a pure-state ensemble consisting of (not necessarily independent) rank-one density operators, then we show that the optimal measurement is a pure-state measurement consisting of rank-one measurement operators.Comment: Submitted to IEEE Transactions on Information Theor

Organizational Citizenship Behaviours - Antecedents, Outcomes & Paradoxes: A Literature Review

Organizational Citizenship Behaviours(OCBs) have asignificant impact on how employees go over and beyondat the workplace and form a competitive edge for theirfirms. Grounded in industrial-organizational psychology,OCBs provide insights for leaders and managers to alignand engage staff to improve organizational effectiveness.While a lot of studies have focused on the benefits ofcitizenship behaviours, there are paradoxes which needmore attention. This paper reviews the literature onOCBs, the antecedents, outcomes and paradoxes whenexcessive OCBs can come in the way of organizationalsuccess

APPLICATION FOR PROVIDING ACCURATE PHOTO TIMESTAMP

An application for providing a photo with an accurate timestamp in a computing device is disclosed. The application displays the correct time of the captured photo, and uses image processing and backend logic to fix the timestamp and location for the photo within a few hours of that time. Using the application, a user can geolocate each photo which can result in improved photo classification and searching

Investigations of Novel Mechanisms of Action for Anti-Bacterial and Anti-Cancer Agent Development

The development of drugs and therapeutic agents for combating infections and human malignancies continues to be a forefront area in both academic and industrial research. This is driven by the rapid emergence of multi-drug resistant bacterial strains and accumulating mutations in cancer targets that is quickly rendering our current arsenal of drugs ineffective for these therapies. Unless new drugs with novel mechanisms of action are identified and developed at a faster pace, we face a losing battle in managing these diseases. The first part of this work concerns with the natural product Simocyclinone D8 (SD8). Simocyclinone D8 is an angucyclinone antibiotic that inhibits DNA gyrase with a novel mechanism of action that has been termed competitive inhibition. Simocyclinone D8 was found to inhibit the growth of both Gram-(+ve) and Gram-(–ve) organisms and also inhibit a fluoroquinolone resistant mutant of DNA gyrase. Inspired by the structure and novel mechanism of action that SD8 displays, we synthesized analogues based on the co-crystal structure of SD8 with DNA gyrase. These compounds were found to inhibit DNA gyrase, albeit by a different mechanism of action than that of SD8. We also conducted studies towards the total chemical synthesis of SD8 and made three out of the four fragments in SD8 in decent yields. The second part of this work is focused on the development of a substrate-competitive covalent inhibitor for protein kinase B (AKT). AKT is a valid target for cancer research with two compounds currently in late stage clinical trials. Developing substrate- competitive inhibitors for kinases is a novel approach in targeting them, with very few examples in the literature. This mechanism has been postulated to overcome common resistance mutations that cancer targets harbor. A major drawback in this approach is the low binding affinity for peptide substrates by kinases. We circumvented this problem of affinity by utilizing a covalent mode of binding and synthesized a potent non-peptide active-site directed irreversible compound that inhibits AKT. Further studies on this compound are underway and are expected to yield a compound that can be used as a therapeutic agent or as a probe for AKT

Solid angle subtended by a cylindrical detector at a point source in terms of elliptic integrals

The solid angle subtended by a right circular cylinder at a point source located at an arbitrary position generally consists of a sum of two terms: that defined by the cylindrical surface ($\Omega_{cyl}$) and the other by either of the end circles ($\Omega_{circ}$). We derive an expression for $\Omega_{cyl}$ in terms of elliptic integrals of the first and third kinds and give similar expressions for $\Omega_{circ}$ using integrals of the first and second kinds. These latter can be used alternatively to an expression also in terms of elliptic integrals, due to Philip A. Macklin and included as a footnote in Masket (Rev. Sci. Instr., 28 (3), 191-197, 1957). The solid angle subtended by the whole cylinder when the source is located at an arbitrary location can then be calculated using elliptic integrals.Comment: 10 pages, 3 figures, LaTex. Typos corrected. References added. Accepted in Rad. Phys. Che