Bow-Tie Microstrip Antenna Design

In this paper, the bow-tie microstrip antennas have been designed with two different angles of 40° and 80°. An investigaton on the effect of the angle to the return loss and radiation patterns had been carried out. The impedance matching network with the niicrostrip transmission line feeding was used in this study. Simulation and measurement results for the return loss and radiation patterns were presented

The Twin Higgs: Natural Electroweak Breaking from Mirror Symmetry

We present `twin Higgs models', simple realizations of the Higgs as a pseudo-Goldstone boson that protect the weak scale from radiative corrections up to scales of order 5 - 10 TeV. In the ultra-violet these theories have a discrete symmetry which interchanges each Standard Model particle with a corresponding particle which transforms under a twin or mirror Standard Model gauge group. In addition, the Higgs sector respects an approximate global SU(4) symmetry. When this global symmetry is broken, the discrete symmetry tightly constrains the form of corrections to the pseudo-Goldstone Higgs potential, allowing natural electroweak symmetry breaking. Precision electroweak constraints are satisfied by construction. These models demonstrate that, contrary to the conventional wisdom, stabilizing the weak scale does not require new light particles charged under the Standard Model gauge groups.Comment: 5 pages. Updated to the journal versio

Nephrectomy for a case of intrarenal dermoid cyst: was it an appropriate decision?

Dermoid cyst in a kidney is rarely seen. We report a case of intrarenal dermoid cyst which mimics malignant renal tumour and discuss the dilemma in managing this disease

Patient-Related Barriers to Timely Dialysis Access Preparation: A Qualitative Study of the Perspectives of Patients, Family Members, and Health Care Providers

Rational & Objective A key aspect of smooth transition to dialysis is the timely creation of a permanent access. Despite early referral to kidney care, initiation onto dialysis is still suboptimal for many patients, which has clinical and cost implications. This study aimed to explore perspectives of various stakeholders on barriers to timely access creation. Study Design Qualitative study. Setting & Participants Semi-structured interviews with 96 participants (response rate, 67%), including patients with stage 4 chronic kidney disease (n = 30), new hemodialysis patients with (n = 18) and without (n = 20) permanent access (arteriovenous fistula), family members (n = 19), and kidney health care providers (n = 9). Analytical Approach Thematic analysis. Results Patients reported differential levels of behavioral activation toward access creation: avoidance/denial, wait and see, or active intention. 6 core themes were identified: (1) lack of symptoms, (2) dialysis fear and practical concerns (exaggerated fear, pain, cost, lifestyle disruptions, work-related concerns, burdening their families), (3) evaluating value against costs/risks of access creation (benefits, threat of operation, viability, prompt for early initiation), (4) preference for alternatives, (5) social influences (hearsay, family involvement, experiences of others), and (6) health care provider interactions (mistrust, interpersonal tension, lack of clarity on information). Themes were common to all groups, whereas nuanced perspectives of family members and health care providers were noted in some subthemes. Limitations Response bias. Conclusions Individual, interpersonal, and psychosocial factors compromise dialysis preparation and contribute to suboptimal dialysis initiation. Our findings support the need for interventions to improve patient and family engagement and address emotional concerns and misperceptions about preparing for dialysis

Pair production of charged Higgs bosons in the Left-Right Twin Higgs model at the ILC and LHC

Left-Right twin Higgs(LRTH) model predicts the existence of a pair of charged Higgs $\phi^{\pm}$. In this paper, we study the production of the charged Higgs bosons pair $\phi^{\pm}$ via the process $e^{+}e^{-}\to \phi^{+}\phi^{-}$ at the International Linear Collider(ILC). The numerical results show that the production rates are at the level of several tens fb, this process can produce the adequate distinct multi-jet final states and the SM background can be efficiently reduced. We also discuss the charged Higgs boson pair production via the process $q\bar{q}\to \phi^{+}\phi^{-}$ at the $CERN$ Large Hadron Collider(LHC) and estimate there production rates. We find that, as long as the charged Higgs bosons are not too heavy, they can be abundantly produced at the LHC. The possible signatures of these new particles might be detected at the ILC and LHC experiments.Comment: 15 pages, 5 figures, discussion extended, reference added, typos fixed, revised version to be published in Eur.Phys.J.

Nambu-Goldstone Dark Matter and Cosmic Ray Electron and Positron Excess

We propose a model of dark matter identified with a pseudo-Nambu-Goldstone boson in the dynamical supersymmetry breaking sector in a gauge mediation scenario. The dark matter particles annihilate via a below-threshold narrow resonance into a pair of R-axions each of which subsequently decays into a pair of light leptons. The Breit-Wigner enhancement explains the excess electron and positron fluxes reported in the recent cosmic ray experiments PAMELA, ATIC and PPB-BETS without postulating an overdensity in halo, and the limit on anti-proton flux from PAMELA is naturally evaded.Comment: 3 figure

Chemical Pressure and Physical Pressure in BaFe_2(As_{1-x}P_{x})_2

Measurements of the superconducting transition temperature, T_c, under hydrostatic pressure via bulk AC susceptibility were carried out on several concentrations of phosphorous substitution in BaFe_2(As_{1-x}P_x)_2. The pressure dependence of unsubstituted BaFe_2As_2, phosphorous concentration dependence of BaFe_2(As_{1-x}P_x)_2, as well as the pressure dependence of BaFe_2(As_{1-x}P_x)_2 all point towards an identical maximum T_c of 31 K. This demonstrates that phosphorous substitution and physical pressure result in similar superconducting phase diagrams, and that phosphorous substitution does not induce substantial impurity scattering.Comment: 5 pages, 4 figures, to be published in Journal of the Physical Society of Japa

Disappearing scales in carps: Re-visiting Kirpichnikov's model on the genetics of scale pattern formation

The body of most fishes is fully covered by scales that typically form tight, partially overlapping rows. While some of the genes controlling the formation and growth of fish scales have been studied, very little is known about the genetic mechanisms regulating scale pattern formation. Although the existence of two genes with two pairs of alleles (S&s and N&n) regulating scale coverage in cyprinids has been predicted by Kirpichnikov and colleagues nearly eighty years ago, their identity was unknown until recently. In 2009, the ‘S’ gene was found to be a paralog of fibroblast growth factor receptor 1, fgfr1a1, while the second gene called ‘N’ has not yet been identified. We re-visited the original model of Kirpichnikov that proposed four major scale pattern types and observed a high degree of variation within the so-called scattered phenotype due to which this group was divided into two sub-types: classical mirror and irregular. We also analyzed the survival rates of offspring groups and found a distinct difference between Asian and European crosses. Whereas nude × nude crosses involving at least one parent of Asian origin or hybrid with Asian parent(s) showed the 25% early lethality predicted by Kirpichnikov (due to the lethality of the NN genotype), those with two Hungarian nude parents did not. We further extended Kirpichnikov's work by correlating changes in phenotype (scale-pattern) to the deformations of fins and losses of pharyngeal teeth. We observed phenotypic changes which were not restricted to nudes, as described by Kirpichnikov, but were also present in mirrors (and presumably in linears as well; not analyzed in detail here). We propose that the gradation of phenotypes observed within the scattered group is caused by a gradually decreasing level of signaling (a dose-dependent effect) probably due to a concerted action of multiple pathways involved in scale formation

Economic Constrained Transfer Capability Assessment

Following the deregulation of electric power utilities around the globe, it has been widely acknowledged that quantifying power system transfer capability is of increasingly importance in today's large-scale and interconnected power system operation and planning procedures. This paper introduces a novel framework to evaluate transfer capability incorporating electricity market dispatching considerations, which we termed it as economic constrained transfer capability (ETC) problem. A mathematical model of a multi-objective optimization (MOOP) approach is presented to solve this ETC problem. The proposed methodology has been tested on a classical 3-machine 9-bus system and the IEEE 30-bus system. Preliminary simulation results from several case studies are presented with relevant analyses and discussions