bluuebunny/crossref_metadata_2025 huggingface dataset:
Can Operators Play a Role in Plant Design?
Authors: Qureshi Naeem
Published: September 2013

Operator involvement during all stages of water treatment plant design and construction produces favorable results. When operators have ownership in a project, they'll go beyond the call of duty to efficiently operate the plant.
Dementia: An Evidence-Based Review of Common Presentations and Family-Based Interventions
Authors: Buffington Angela L.H. , Lipski Dorothy M. , Westfall Erin
Published: September 2013

The number of US older adults with dementia is expected to grow over the next several decades. For instance, the number of persons with Alzheimer disease is predicted to increase by 50% by 2030. Physicians commonly come into contact with patients who have dementia and, as such, need to understand its varied presentation. In the current review, the most common types of dementia, including Alzheimer disease, frontotemporal dementia, dementia due to vascular disease, and several others, are described. Characteristics and etiologic findings of cortical and subcortical dementias are differentiated, and cognitive profiles and symptoms of specific types of dementia are reviewed. An osteopathic approach to care, focusing on establishing a relationship with patients and their families, is also discussed.
Medicare Reform and Primary Care Concerns for Future Physicians
Authors: Mitchell Charles H. , Spinelli Robert J.
Published: September 2013

The widening income gap between specialists and primary care physicians (PCPs) has spurred many physician associations to reform the current Resource-Based Relative Value Scale fee schedule and sustainable growth rate expenditure target system. Hoping to better represent primary care, the American Association of Family Physicians formed a task force in 2011 to suggest supplements to the Relative Value Update Committee's procedural code recommendations to the Centers for Medicare and Medicaid Services. In addition, the predicted shortage of PCPs has caused many medical schools to increase class sizes; the scarcity of PCPs has also spurred the founding of new medical schools. Such measures, however, have not been met with more residency program sites or graduate medical education funding. The present article highlights major Medicare reform strategies and explores several issues affecting the field of primary care, including reimbursement, representation, and residency training.
Combining higher-order resummation with multiple NLO calculations and parton showers in GENEVA
Authors: Alioli Simone , Bauer Christian W. , Berggren Calvin , Hornig Andrew , Tackmann Frank J. , Vermilion Christopher K. , Walsh Jonathan R. , Zuberi Saba
Published: September 2013

Abstract

We extend the lowest-order matching of tree-level matrix elements with parton showers to give a complete description at the next higher perturbative accuracy in α

s
at both small and large jet resolutions, which has not been achieved so far. This requires the combination of the higher-order resummation of large Sudakov logarithms at small values of the jet resolution variable with the full next-to-leading-order (NLO) matrix-element corrections at large values. As a by-product, this combination naturally leads to a smooth connection of the NLO calculations for different jet multiplicities. In this paper, we focus on the general construction of our method and discuss its application to e
+
e
− and pp collisions. We present first results of the implementation in the Geneva Monte Carlo framework. We employ N-jettiness as the jet resolution variable, combining its next-to-next-to-leading logarithmic resummation with fully exclusive NLO matrix elements, and Pythia 8 as the backend for further parton showering and hadronization. For hadronic collisions, we take Drell-Yan production as an example to apply our construction. For e
+
e
− → jets, taking α

s
(m
Z) = 0.1135 from fits to LEP thrust data, together with the Pythia 8 hadronization model, we obtain good agreement with LEP data for a variety of 2-jet observables.
Estimation of the ecosystem carbon budget in South Korea between 1999 and 2008
Authors: Yoo Seongjin , Kwak Doo‐Ahn , Cui Guishan , Lee Woo‐Kyun , Kwak Hanbin , Ito Akihiko , Son Yowhan , Jeon Seongwoo
Published: September 2013

A carbon flux model, the vegetation integrated simulator for trace gases, was employed to estimate the carbon budgets of vegetation ecosystems in South Korea. The geographic information system was used to prepare the input variables for the model, such as climate, soil, and land‐cover data, from reliable national inventories. Model simulation results indicated that the annual average gross primary production, net primary production, and soil respiration (SR) for 10 years were 91.89, 40.16, and 62.91 Tg C year−1, respectively. The model also estimated a net ecosystem production with a value of 3.51 Tg C year−1 between 1999 and 2008. Such results indicate that the vegetation ecosystems of South Korea offset 3.3 % of anthropogenic emissions as a net carbon sink. Latitudinal and topographical gradients over the total simulation area were found for all estimates. In addition, the estimates varied between seasons and years, especially in estimates for biomass growth and carbon uptake, because of variations in the weather conditions. Finally, model validation was conducted using measured soil efflux and flux measurement data from the Gwangneung experimental forest (GEF). The estimated SR accounted for 81.6 % of the observed SR at the GEF site (P < 0.005). Further, the model accounted well for the observed phase and amplitude of changes in the summer and autumn seasons.
Coupling Device and Distal Femoral Replacement for Periprosthetic Supracondylar Femur Fractures with an Ipsilateral Total Knee and Hip Replacement
Authors: Grosso Matthew J. , Lipman Joseph , Bostrom Mathias P.
Published: September 2013

Background

Periprosthetic supracondylar fractures in the setting of an ipsilateral total knee and hip replacement are a rare but serious orthopedic challenge.

Description of Technique

In this unique situation, we consider insertion of a custom coupling device with a distal femoral replacement as an appropriate surgical solution that allows for stability and preserves hip and knee functionality, while not relying on the poor healing potential of the remaining intercalary femoral bone.

Patients and Methods

We report the outcomes of two patients who underwent this custom coupling procedure.

Results

These custom devices resulted in successful outcomes with restoration of ambulatory function and range of motion at greater than 14 months follow-up.

Conclusions

We found that this technique provides sufficient stability and preserves functionality in a difficult-to-treat patient population. The results indicate that this technique may be considered as an alternative to more invasive procedures including total femoral replacement and complete femoral allograft constructs.
Chronic lymphocytic leukemia in Kenya: an immunophenotypic and clinicopathologic study
Authors: Mulwa-Babu E. , Paresh D. , Riyat M.
Published: September 2013

Objective

To define cases of chronic lymphocytic leukemia (CLL) by immunophenotypic criteria and describe the associated clinical features in patients diagnosed at Aga Khan University Hospital, Nairobi.

Background

Rising to the growing cancer challenge will require improved diagnostic services. CLL is common in elderly patients. The current international standard in diagnosis incorporates findings of immunophenotyping. Facilities for immunophenotyping have generally been unavailable in Kenya.

Method

A cross-sectional survey was conducted between August 2011 and April 2012. Potential cases were identified based on morphologic criteria. Consecutive samples were obtained and subjected to 3 colour immunophenotyping on a Cytomics FC 500 cytometer. CLL was defined using the Royal Marsden Hospital scoring system. Baseline clinical and diagnostic data were also obtained.

Results

Forty nine cases met the eligibility criteria. Thirty one were known CLL cases, and 18 were newly diagnosed. Median age at diagnosis was 62 years. Male:female ratio was 1.3:1. Black patients (42/49) were more likely to present with high risk disease (Rai stages III-IV) and with higher lymphocyte counts than non-blacks at diagnosis. Twenty six point five percent of patients in this study were diagnosed in Rai stage 0. The prevalence of CD5/CD23 co-expression was found to be 95.9%. CD5 was universally expressed, whereas CD23 was present in all but 2 cases. Both were associated with atypical morphology. Complete absence of light chain expression using a monoclonal antibody was found in 12.2% of cases. Five patients had their diagnosis revised. Of 31 patients on follow-up for CLL, only 5 had had any form of immunophenotyping done.
Forced‐Air Warming Devices and the Risk of Surgical Site Infections
Authors: Kellam Melissa D. , Dieckmann Loraine S. , Austin Paul N.
Published: September 2013

The potential that forced‐air warming systems may increase the risk of surgical site infections (SSIs) by acting as a vector or causing unwanted airflow disturbances is a concern to health care providers. To investigate this potential, we examined the literature to determine whether forced‐air warming devices increase the risk of SSIs in patients undergoing general, vascular, or orthopedic surgical procedures. We examined 192 evidence sources, 15 of which met our inclusion criteria. Most sources we found indirectly addressed the issue of forced‐air warming and only three studies followed patients who were warmed intraoperatively with forced‐air warming devices to determine whether there was an increased incidence of SSIs. All of the sources we examined contained methodological concerns, and the evidence did not conclusively suggest that the use of forced‐air warming systems increases the risk of SSIs. Given the efficacy of these devices in preventing inadvertent perioperative hypothermia, practitioners should continue to use and clean forced‐air warming systems according to the manufacturer's instructions until well‐conducted, large‐scale trials can further examine the issue.
Redes y clusters para la innovación y la transferencia del conocimiento. Impactoen el crecimiento regional en Argentina
Authors: De Arteche Mónica , Santucci Marina , Welsh Sandra Vanessa
Published: September 2013

En el presente documento se realiza un análisis de la situación de los principales clusters de Argentinay cómo estas estructuras asociativas pueden mejorar la generación de innovaciones y generar externa-lidades positivas para la comunidad. Lo anterior se realiza a través de un análisis de tipo descriptivo,abordando el objeto de investigación mediante el estudio de casos. Asimismo se aplicó un modelo degestión de conocimiento con el fin de evaluar los efectos de los clusters en la innovación y la creación deconocimiento valioso. Como conclusión se pudo demostrar la importancia del apoyo institucional desdelas políticas públicas, las características estructurales que deben poseer los clusters y las acciones paradesarrollar el capital estructural, relacional y de innovación
Successes and challenges of establishing a cervical cancer screening and treatment program in western Kenya
Authors: Khozaim Kareem , Orang'o Elkanah , Christoffersen‐Deb Astrid , Itsura Peter , Oguda John , Muliro Hellen , Ndiema Jackline , Mwangi Grace , Strother Matthew , Cu‐Uvin Susan , Rosen Barry , Washington Sierra
Published: September 2013

Objective

To describe the challenges and successes of integrating a public‐sector cervical screening program into a large HIV care system in western Kenya.

Methods

The present study was a programmatic description and a retrospective chart review of data collected from a cervical screening program based on visual inspection with acetic acid (VIA) between June 2009 and October 2011.

Results

In total, 6787 women were screened: 1331 (19.6%) were VIA‐positive, of whom 949 (71.3%) had HIV. Overall, 206 women underwent cryotherapy, 754 colposcopy, 143 loop electrical excision procedure (LEEP), and 27 hysterectomy. Among the colposcopy‐guided biopsies, 27.9% had severe dysplasia and 10.9% had invasive cancer. There were 68 cases of cancer, equating to approximately 414 per 100 000 women per year. Despite aggressive strategies, the overall loss to follow‐up was 31.5%: 27.9% were lost after a positive VIA screen, 49.3% between biopsy and LEEP, and 59.6% between biopsy and hysterectomy/chemotherapy.

Conclusion

The established infrastructure of an HIV treatment program was successfully used to build capacity for cervical screening in a low‐resource setting. By using task‐shifting and evidence‐based, low‐cost approaches, population‐based cervical screening in a rural African clinical network was found to feasible; however, loss to follow‐up and poor pathology infrastructure remain important obstacles.
Patient‐reported outcome of solifenacin treatment among women experiencing urinary urgency and urgency incontinence
Authors: But Igor , Orešković Slavko , Bratuš Dejan , Šprem‐Goldštajn Marina , Hlebič Gregor
Published: September 2013

Objective

To evaluate treatment success and tolerability of solifenacin among women with urinary urgency (UU) and urgency urinary incontinence (UUI).

Methods

In a prospective, observational, multicenter pilot study in Slovenia and Croatia, 100 women with UU and UUI were enrolled between January 2011 and July 2011. Patients received 5 mg of solifenacin once daily for 12 weeks and completed a 3‐day bladder diary, urgency questionnaire, Urogenital Distress Inventory (UDI), and Incontinence Impact Questionnaire (IIQ).

Results

Overall, 91 women completed 12 weeks of treatment. Severity, frequency, and bother of UU significantly had decreased at weeks 4 and 12 (P < 0.001). Improvement in UU led to an improvement in mean IIQ score: a reduction in UU frequency had the greatest impact (P = 0.006). The mean treatment success rate was 74.2% (by visual analog score) and was closely related to the mean change in irritative UDI score (r = 0.39; P < 0.001). Treatment success was greatest for patient perception of intensity of urgency scale (PPIUS; P = 0.003), UU bother (P = 0.017), and micturition frequency (P < 0.026). Dry mouth occurred in 35.2% of women at 4 weeks, and 27.7% at week 12.

Conclusion

Solifenacin treatment was effective and well‐tolerated among women with UU and UUI. All overactive bladder symptoms had improved by week 12.
Patterns of Outdoor Recreational Injury in Northern British Columbia
Authors: Besserer Floyd A. , Caron Nadine R.
Published: September 2013

Objective

The objective of this study was to examine the patterns of severe injury documented at a northern British Columbia regional trauma center based on age, sex, month of year, activity type, injury type, and injury severity as they relate to participation in outdoor recreational activities.

Methods

A retrospective analysis of data abstracted from the British Columbia Trauma Registry for patients sustaining injuries between April 1, 2004, and March 31, 2007, while engaged in outdoor recreational activities in the Northern Health Authority. The British Columbia Trauma Registry inclusion criteria are as follows: 1) admitted for treatment of injuries sustained from the transfer of external energy or force; 2) admitted to the facility within 7 days of injury; and 3) length of stay more than 2 days or in-hospital mortality.

Results

In all, 159 patients met study criteria. August and September were peak injury months (mean 7.3 and 7.0 per month, respectively). The highest injury patterns involved cycling ( n = 31), all-terrain vehicle operation ( n = 30), horseback riding ( n = 22), and snowmobiling ( n = 22). Of the 159 patients, 76.1% were male, with a peak age distribution between 10 years and 19 years (22%). Males were more commonly injured than females among cycling (83.9%), all-terrain vehicle (86.7%), and snowmobile (100%) traumas. Females were more commonly injured from horseback riding events (42.1%).

Conclusions

This study emphasizes the need for rapid translation of research findings into injury prevention awareness and programming in northern British Columbia, particularly relating to cycling, horseback riding, snowmobiling, and all-terrain vehicle operation. Further investigation is required to analyze long-term outcomes for this common injury population.
Active suspensions in thin films: nutrient uptake and swimmer motion
Authors: Lambert Ruth A. , Picano Francesco , Breugem Wim-Paul , Brandt Luca
Published: September 2013

A numerical study of swimming particle motion and nutrient transport is conducted for a semidilute to dense suspension in a thin film. The steady squirmer model is used to represent the motion of living cells in suspension with the nutrient uptake by swimming particles modelled using a first-order kinetic equation representing the absorption process that occurs locally at the particle surface. An analysis of the dynamics of the neutral squirmers inside the film shows that the vertical motion is reduced significantly. The mean nutrient uptake for both isolated and populations of swimmers decreases for increasing swimming speeds when nutrient advection becomes relevant as less time is left for the nutrient to diffuse to the surface. This finding is in contrast to the case where the uptake is modelled by imposing a constant nutrient concentration at the cell surface and the mass flux results to be an increasing monotonic function of the swimming speed. In comparison to non-motile particles, the cell motion has a negligible influence on nutrient uptake at lower particle absorption rates since the process is rate limited. At higher absorption rates, the swimming motion results in a large increase in the nutrient uptake that is attributed to the movement of particles and increased mixing in the fluid. As the volume fraction of swimming particles increases, the squirmers consume slightly less nutrients and require more power for the same swimming motion. Despite this increase in energy consumption, the results clearly demonstrate that the gain in nutrient uptake make swimming a winning strategy for micro-organism survival also in relatively dense suspensions.
Levitation of a drop over a moving surface
Authors: Lhuissier Henri , Tagawa Yoshiyuki , Tran Tuan , Sun Chao
Published: September 2013

We investigate the levitation of a drop gently deposited onto the inner wall of a rotating hollow cylinder. For a sufficiently large velocity of the wall, the drop steadily levitates over a thin air film and reaches a stable angular position in the cylinder, where the drag and lift balance the weight of the drop. Interferometric measurements yield the three-dimensional (3D) air film thickness under the drop and reveal the asymmetry of the profile along the direction of the wall motion. A two-dimensional (2D) model is presented which explains the levitation mechanism, captures the main characteristics of the air film shape and predicts two asymptotic regimes for the film thickness ${h}_{0} $: for large drops ${h}_{0} \sim {\mathit{Ca}}^{2/ 3} { \kappa }_{b}^{- 1} $, as in the Bretherton problem, where $\mathit{Ca}$ is the capillary number based on the air viscosity and ${\kappa }_{b} $ is the curvature at the bottom of the drop; for small drops ${h}_{0} \sim {\mathit{Ca}}^{4/ 5} {(a{\kappa }_{b} )}^{4/ 5} { \kappa }_{b}^{- 1} $, where $a$ is the capillary length.
Comparative study of flexible nasoendoscopic and rigid endoscopic examination for patients with upper aerodigestive tract symptoms
Authors: Fleming J C , Al-Radhi Y , Kurian A , Mitchell D B
Published: September 2013

Introduction:

The objective of the current study was to compare the outcomes of rigid endoscopic procedures with those of pre-operative flexible nasoendoscopy.

Methods:

A total of 253 patients who had undergone rigid endoscopic examination under anaesthesia between 6 January 2010 and 31 August 2011 were identified. Their clinical, surgical and histological records were evaluated.

Results:

A total of 213 patients had a flexible nasoendoscopic procedure performed and recorded pre-operatively, and 82 in this cohort had a specific lesion or area of concern identified. There were 21 confirmed malignant biopsy results, the majority of which were squamous cell carcinoma. No patient with a negative pre-operative endoscopy had a malignant lesion discovered on endoscopic biopsy. The sensitivity and specificity of pre-operative nasoendoscopy were 100 per cent and 66.3 per cent, respectively.

Conclusion:

Diagnostic rigid endoscopic examination of the upper aerodigestive tract remains an important tool for excluding malignancy in high-risk patients, but is an unnecessary procedure in those low-risk patients with normal pre-operative findings.
On the elliptic points of the Hilbert modular group of the totally real cyclotomic cubic field ℚ(ζ9)+
Authors: Arenas A.
Published: September 2013

We determine explicitly the elliptic points with respect to the Hilbert modular group associated with the totally real cyclotomic cubic field ℚ(ζ + ζ−1), where ζ stands for a primitive 9th root of unity.
Patient-centered assessment of cognitive symptoms of depression
Authors: Fehnel Sheri E. , Forsyth Barbara H. , DiBenedetti Dana B. , Danchenko Natalya , François Clément , Brevig Thomas
Published: September 2013

Objective

To identify and explore concepts important to patients with cognitive symptoms of major depressive disorder (MDD) and adapt an existing patient-reported outcome (PRO) measure to assess these symptoms.

Methods

Four focus groups were conducted with MDD patients (n = 33) to elicit relevant concepts and determine whether one of several PRO scales could be used to assess cognitive symptoms of depression. Following selection and minor modification of the Perceived Deficits Questionnaire (PDQ), cognitive debriefing interviews were conducted with additional patients (n = 17) to further refine and adapt this measure for use in MDD. Minor revisions based on patient input yielded the PDQ for Depression (PDQ-D).

Results

Focus group participants reported a variety of cognitive symptoms that were classified into 7 general categories: lack of focus and clear thought, memory problems, difficulty with lexical access, difficulty with divided attention, difficulty with decision making, difficulty thinking quickly, and difficulty learning new things. Limitations in work productivity were the most commonly reported impacts of cognitive symptoms. While suggesting a few modifications, focus group participants reacted positively to the PDQ based on the breadth, specificity, and relevance of the items. Cognitive debriefing participants indicated that the modified PDQ items were generally easy to understand and relevant to their experiences with MDD.

Conclusion

Because cognitive symptoms are burdensome to patients with MDD, their assessment is important to optimize treatment outcomes. The PDQ-D has the potential to supplement existing assessment methods, providing unique information important for both comprehensive evaluation of individuals with MDD and evaluation of new treatments.
Lloyd-Topor completion and general stable models
Authors: LIFSCHITZ VLADIMIR , YANG FANGKAI
Published: September 2013

We investigate the relationship between the generalization of program completion defined in 1984 by Lloyd and Topor and the generalization of the stable model semantics introduced recently by Ferraris et al. The main theorem can be used to characterize, in some cases, the general stable models of a logic program by a first-order formula. The proof uses Truszczynski's stable model semantics of infinitary propositional formulas.
A CLP heap solver for test case generation
Authors: ALBERT ELVIRA , DE LA BANDA MARÍA GARCÍA , GÓMEZ-ZAMALLOA MIGUEL , ROJAS JOSÉ MIGUEL , STUCKEY PETER
Published: September 2013

One of the main challenges to software testing today is to efficiently handle heap-manipulating programs. These programs often build complex, dynamically allocated data structures during execution and, to ensure reliability, the testing process needs to consider all possible shapes these data structures can take. This creates scalability issues since high (often exponential) numbers of shapes may be built due to the aliasing of references. This paper presents a novel CLP heap solver for the test case generation of heap-manipulating programs that is more scalable than previous proposals, thanks to the treatment of reference aliasing by means of disjunction, and to the use of advanced back-propagation of heap related constraints. In addition, the heap solver supports the use of heap assumptions to avoid aliasing of data that, though legal, should not be provided as input.
Compact serialization of Prolog terms (with catalan skeletons, cantor tupling and Gödel numberings)
Authors: TARAU PAUL
Published: September 2013

We describe a compact serialization algorithm mapping Prolog terms to natural numbers of bit-sizes proportional to the memory representation of the terms. The algorithm is a ‘no bit lost’ bijection, as it associates to each Prolog term a unique natural number and each natural number corresponds to a unique syntactically well-formed term.

To avoid an exponential explosion resulting from bijections mapping term trees to natural numbers, we separate the symbol content and the syntactic skeleton of a term that we serialize compactly using a ranking algorithm for Catalan families.

A novel algorithm for the generalized Cantor bijection between ${\mathbb{N}$ and ${\mathbb{N}$k is used in the process of assigning polynomially bounded Gödel numberings to various data objects involved in the translation.
Combining decidability paradigms for existential rules
Authors: GOTTLOB GEORG , MANNA MARCO , PIERIS ANDREAS
Published: September 2013

Existential rules are Datalog rules extended with existential quantifiers in rule-heads. Three fundamental restriction paradigms that have been studied for ensuring decidability of query answering under existential rules are weak-acyclicity, guardedness and stickiness. Towards the identification of even more expressive decidable languages, several attempts have been conducted to consolidate weak-acyclicity with the other two paradigms. However, it is not clear how guardedness and stickiness can be merged; this is the subject of this paper. A powerful and flexible condition, called tameness, is proposed, which allows us to consolidate in an elegant and uniform way guardedness with stickiness.
Late Cretaceous mosasauroids (Reptilia, Squamata) of the Big Bend region in Texas, USA
Authors: Bell Gorden L. , Barnes Kenneth R. , Polcyn Michael J.
Published: September 2013

Upper Cretaceous marine rocks of the Big Bend Region of trans-Pecos Texas preserve a number of marine-adapted mosasauroids. At least three unnamed taxa of basal mosasauroids are represented by remains from shaly limestones in the middle Turonian portion of the Boquillas Formation. These occur along with remains of larger derived mosasaurs referable to Russellosaurina and an undescribed tylosaurine. Derived mosasaurs from the middle to late Coniacian include the first report of Tylosaurus kansasensis outside of Kansas, T. nepaeolicus, Platecarpus planifrons, and Platecarpus aff. P. planifrons. Clidastes liodontus is found in the latest Coniacian or early Santonian part of the Pen Formation. An undescribed species of Ectenosaurus, Clidastes sp. and an indeterminate plioplatecarpine occurs in the middle Santonian to early Campanian interval of the Pen Formation. The mosasaur fauna from the Big Bend region is quite similar to that from the Smoky Hill Chalk of Kansas, a thousand kilometres to the north. We refine the position of the Cenomanian–Turonian boundary within the Ernst Member of the Boquillas Formation, based on ammonite faunas. We also corroborate previous interpretations describing the time-transgressive nature of the onset of deposition of the Pen Formation based on a west-to-east descending level of the Inoceramus (Cremnoceramus) undulatoplicatus FAD.
A K-band delay line based on parasitic reduced artificial left-handed transmission line
Authors: Lee Hyun-Seung , Lee Eun-Gyu , Kim Choul-Young
Published: September 2013

A K-band microstrip delay line based on parasitic reduced left-handed transmission line (LHTL) with interdigital capacitors and shunt inductors is demonstrated with the aid of printed circuit board technology. The proposed delay line has ground slots under the interdigital capacitors to reduce the parasitic capacitance. The time delay of the proposed LHTLs is approximately 2.6 times larger than that of the conventional LHTLs. The input return loss of the proposed LHTL at 24 GHz is −16.9 dB and less than −10 dB from 20.5 to 26.1 GHz.
Novel dual-band multistrip monopole antenna with defected ground structure for WLAN/IMT/BLUETOOTH/WIMAX applications
Authors: Kaur Jaswinder , Khanna Rajesh , Kartikeyan Machavaram
Published: September 2013

In the present work, a novel multistrip monopole antenna fed by a cross-shaped stripline comprising one vertical and two horizontal strips has been proposed for wireless local area network (WLAN)/Industrial, Scientific, and Medical band (ISM)/International Mobile Telecommunication (IMT)/BLUETOOTH/Worldwide Interoperability for Microwave Access (WiMAX) applications. The designed antenna has a small overall size of 20 × 30 mm2. The goal of this paper is to use defected ground structure (DGS) in the proposed antenna design to achieve dual-band operation with appreciable impedance bandwidth at the two operating modes satisfying several communication standards simultaneously. The antenna was simulated using Computer Simulation Technology Microwave Studio (CST MWS) V9 based on the finite integration technique (FIT) with perfect boundary approximation. Finally, the proposed antenna was fabricated and some performance parameters were measured to validate against simulation results. The design procedure, parametric analysis, simulation results along with measurements for this multistrip monopole antenna using DGS operating simultaneously at WLAN (2.4/5.8 GHz), IMT (2.35 GHz), BLUETOOTH (2.45 GHz), and WiMAX (5.5 GHz) are presented.
On the self-organizing process of large scale shear flows
Authors: Newton Andrew P. L. , Kim Eun-jin , Liu Han-Li
Published: September 2013

Self organization is invoked as a paradigm to explore the processes governing the evolution of shear flows. By examining the probability density function (PDF) of the local flow gradient (shear), we show that shear flows reach a quasi-equilibrium state as its growth of shear is balanced by shear relaxation. Specifically, the PDFs of the local shear are calculated numerically and analytically in reduced 1D and 0D models, where the PDFs are shown to converge to a bimodal distribution in the case of finite correlated temporal forcing. This bimodal PDF is then shown to be reproduced in nonlinear simulation of 2D hydrodynamic turbulence. Furthermore, the bimodal PDF is demonstrated to result from a self-organizing shear flow with linear profile. Similar bimodal structure and linear profile of the shear flow are observed in gulf stream, suggesting self-organization.
Microstructure, magnetic and electrical transport properties of melt-spun Ni-Mn-Sb ribbons
Authors: Ray Mayukh K. , Bagani K. , Singh R. K. , Majumdar B. , Banerjee S.
Published: September 2013

The Ni50Mn37Sb13 ribbons were prepared by melt-spinning technique to overcome the brittleness of bulk. A single phase austenite with L21 structure was confirmed in the as-spun and annealed ribbons at room temperature similar to bulk. We observe increments in the martensite transformation temperature (TM) from 238 K to 252 K and in Curie temperature of austenite phase (TCA) from 336 K to 342 K after annealing the as-spun ribbon. The exchange bias, magnetic entropy change (ΔSM), and magnetoresistance are found to increase from 380 Oe to 415 Oe, 1 J/kg-K to 3 J/kg-K (ΔH=50 kOe), and −4% to −13% (ΔH=50 kOe), respectively, after annealing the as-spun ribbon. The possible reasons for observed behaviour are discussed.
Relaxor nature in lead-free Sr5LaTi3Nb7O30 tetragonal tungsten bronze ceramics
Authors: Li Zhu Xiao , Li Kun , Asif Rafiq Muhammad , Qiang Liu Xiao , Ming Chen Xiang
Published: September 2013

Lead-free tetragonal tungsten bronze Sr5LaTi3Nb7O30 ceramics were prepared and the correlation of the relaxor nature and crystal structure was studied using dielectric spectroscopy and powder X-ray diffraction. Three dielectric relaxations were observed below the deviation temperature TD ∼ 330 K. Relaxation I and II followed the Vogel-Fulcher law with the freezing temperatures of 189 K and ∼90 K. Low temperature relaxation III, which was first observed in filled tungsten bronze, followed well the Arrhenius law. Dielectric response becomes static below 50 K. Polarization-field (P-E) hysteresis loops were evaluated from 183 K to 298 K. Pr value of 0.41μC/cm2 was observed at 183 K. Deviation of lattice parameter c from the linear contraction and increasing of tetragonality (c/a ratio) were observed below TD, reflecting the structure change during the formation of polar nanoregions and the following freezing process. Opposite tendency was observed below 100 K for all the lattice parameters, corresponding to relaxation III. Generally, the main dielectric relaxation I and II were attributed to flipping and breathing of polar nanoregions along c axis, while the concerted rotations of the oxygen octahedra in the ab plane were suggested as the origin of relaxation III.
Spin rectification induced by dynamical Hanle effect
Authors: Sakimura Hiroto , Matsumoto Takahiko , Ando Kazuya
Published: September 2013

Dynamic response of spin accumulation to a time-dependent magnetic field has been investigated in a ferromagnetic/nonmagnetic bilayer under ferromagnetic resonance. In this system, magnetization precession driven by a microwave generates direct-current (dc) and alternate-current (ac) spin accumulation in the nonmagnetic layer by the spin pumping. The ac spin accumulation is coupled with the microwave magnetic field through a dynamical Hanle spin precession, giving rise to rectified spin accumulation comparable with the dc spin accumulation directly generated by the spin pumping.
Highly luminescent, high-indium-content InGaN film with uniform composition and full misfit-strain relaxation
Authors: Fischer A. M. , Wei Y. O. , Ponce F. A. , Moseley M. , Gunning B. , Doolittle W. A.
Published: September 2013

We have studied the properties of thick InxGa1−xN films, with indium content ranging from x ∼ 0.22 to 0.67, grown by metal-modulated epitaxy. While the low indium-content films exhibit high density of stacking faults and dislocations, a significant improvement in the crystalline quality and optical properties has been observed starting at x ∼ 0.6. Surprisingly, the InxGa1−xN film with x ∼ 0.67 exhibits high luminescence intensity, low defect density, and uniform full lattice-mismatch strain relaxation. The efficient strain relaxation is shown to be due to a critical thickness close to the monolayer range. These films were grown at low temperatures (∼400 °C) to facilitate indium incorporation and with precursor modulation to enhance surface morphology and metal adlayer diffusion. These findings should contribute to the development of growth techniques for nitride semiconductors under high lattice misfit conditions.
Thermal analysis of silver nanoparticles for flexible printed antenna fabrication
Authors: Ankireddy Krishnamraju , Iskander Mina , Vunnam Swathi , Anagnostou Dimitris E. , Kellar Jon , Cross William
Published: September 2013

In this study, the temperature assisted decomposition/desorption behavior of short-chain single and mixed carboxylic acid encapsulants from the core of silver nanoparticles was investigated using thermogravimetric analysis and differential scanning calorimetry, and these particles were used to fabricate a flexible printed antenna. The decomposition temperatures of the single encapsulant particles increased with increasing chain length of encapsulants, whereas the decomposition temperatures for mixed encapsulant particles are close to the average of the corresponding decomposition temperatures of single encapsulant nanoparticles. These experimentally identified decomposition temperatures were utilized for sintering the printed antenna on a flexible substrate. The printed antenna showed a significantly low return loss of 22 dB. The antenna performance and radiation pattern are similar to a reference prototype antenna made of copper.
Decorating Semiconductor Silver-Tetracyanoquinodimethane Nanowires with Silver Nanoparticles from Ionic Liquids
Authors: Zhao Chuan , Xiao Changlong , Chan Hubert M. , Lu Xunyu
Published: September 2013

Hybrid semiconducting silver-tetracyanoquinodimethane (AgTCNQ) nanowires decorated with Ag nanoparticles have been synthesized at room temperature in the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate. Hydroquinone was applied to reduce Ag+ and TCNQ to silver nanoparticles, and TCNQ–, respectively, under ambient conditions. AgTCNQ nanowires were formed via spontaneous electrolysis between Ag metal nanoparticles and TCNQ, and reaction between Ag+ and TCNQ–. Microscopic, spectroscopic, and X-ray characterizations all confirmed the formation of crystalline Ag nanoparticle–AgTCNQ nanowire hybrid structures. The ionic liquid was used as a reaction medium, but also as a stabilizing (or blocking) agent to control the nucleation and growth rate of AgTCNQ wires.
Reproductive cycle of the barred sorubim Pseudoplatystoma fasciatum (Linnaeus, 1766), in the upper delta of the Orinoco River, Delta Amacuro State, Venezuela
Authors: Silva-Acuña Annie , Barrios Alexander José
Published: September 2013

Pseudoplatystoma fasciatum represents one of the most important items in the continental fisheries of Venezuela. The great fishing pressure exerted on this species has decimated the populations in the Orinoco River Delta and other regions of the country. The current condition of the population in the delta region is unknown and information about basic biological parameters is unavailable. Hence, population and reproductive parameters of this catfish were determined in this region. Results showed that the size interval was from 30 to 105 cm total length (TL), generally smaller than the size range found in other regions of the country. The largest value for the gonadal index for females was 116, recorded in July. Size at maturity of 50% of females was 46.38 cm TL, a smaller value than others reported for the Orinoco River Basin. Maturation of oocytes was synchronous, showing a single total spawning per year. The capture of P. fasciatum was continuous throughout the year, including mature individuals during the reproductive season, suggesting a possible utilization of the delta region as reproductive site. A total of 61% of the individuals were below the minimum legal size, indicating deficient management of this fishery resource in the Orinoco River Delta.
Cell-sized liposomes reveal how actomyosin cortical tension drives shape change
Authors: Carvalho Kevin , Tsai Feng-Ching , Lees Edouard , Voituriez Raphaël , Koenderink Gijsje H. , Sykes Cecile
Published: September 2013

Significance

Animal cells continuously move, divide, and transmit forces by actively reorganizing their internal scaffold or cytoskeleton. Molecular motors pull actin filaments together and generate contraction of the cytoskeleton underneath the cell membrane. We address the detailed mechanism of contraction by using a minimal in vitro assay: a liposome membrane to which we attach actin filaments and molecular motors in a controlled manner. We reproduce contraction like in cells. We show that the scaffold needs to be tightly attached to the membrane for efficient contraction, but, under some conditions, efficient contraction can lead to liposome destruction. These results suggest that cells must precisely control their contractility to remain intact during cellular events.
Multiple origins of pyrethroid insecticide resistance across the species complex of a nontarget aquatic crustacean,
Hyalella azteca
Authors: Weston Donald P. , Poynton Helen C. , Wellborn Gary A. , Lydy Michael J. , Blalock Bonnie J. , Sepulveda Maria S. , Colbourne John K.
Published: September 2013

Significance

The crustacean,
Hyalella azteca
, is commonly used in environmental monitoring to test the toxicity of water or sediment. We show that among three laboratory cultures and seven wild populations of
H. azteca
, there is a more than 550-fold variation in sensitivity to widely used pyrethroid insecticides. Some individuals have attained resistance by mutations in the voltage-gated sodium channel, the target site for pyrethroid toxicity. Similar mutations have been found in agricultural pests targeted by pyrethroids, but this study indicates that runoff of terrestially applied urban and agricultural pesticides has been sufficient to induce resistance in a nontarget aquatic species on multiple, independent occasions. Our results have far-reaching implications for biomonitoring programs in general and especially those relying on
H. azteca
.
Adult and larval traits as determinants of geographic range size among tropical reef fishes
Authors: Luiz Osmar J. , Allen Andrew P. , Robertson D. Ross , Floeter Sergio R. , Kulbicki Michel , Vigliola Laurent , Becheler Ronan , Madin Joshua S.
Published: September 2013

Significance

Marine organisms disperse mostly by ocean currents as larval propagules. Therefore, it is commonly thought that the duration of the larval stage is the fundamental determinant of geographic range size. Using a global compilation of reef fish traits, we test an alternative hypothesis: adult traits associated with population establishment and persistence in novel areas are better predictors of geographic range size than larval traits. We conclude that colonization success is as primary determinant of successful range extension and of geographic range size among tropical reef fishes.
Self-organized optical device driven by motor proteins
Authors: Aoyama Susumu , Shimoike Masahiko , Hiratsuka Yuichi
Published: September 2013

Significance

Certain nanomaterials, such as protein molecules, produce various advanced functions when incorporated into an ordered system and, therefore, have large potential for use in engineering devices. To explore how to assemble a functional device from protein components, we have tried to create a molecular device inspired by a fish pigment cell, “melanophore.” We induced ordered assembly of protein molecules through self-organization of the proteins in a specific artificial microstructure and thereby succeeded in producing a melanophore-like optical device. We believe that self-organization of molecules in microstructures can be a powerful method for assembling functional molecular systems in future nanotechnology.
Shear stress triggers insertion of voltage-gated potassium channels from intracellular compartments in atrial myocytes
Authors: Boycott Hannah E. , Barbier Camille S. M. , Eichel Catherine A. , Costa Kevin D. , Martins Raphael P. , Louault Florent , Dilanian Gilles , Coulombe Alain , Hatem Stéphane N. , Balse Elise
Published: September 2013

Significance

The heart is continuously subjected to mechanical forces. The atria in particular are susceptible to changes in the mechanical environment due to their unique position as “pressure sensors.” Here, we show that increased shear stress induces the recruitment of potassium channels from intracellular storage pools to the plasma membrane, via signaling pathways that link the extracellular matrix to the cytoskeleton. This process is altered in myocytes experiencing chronically increased mechanical stress. The incorporation of channels into the membrane causes changes in the electrical activity of the myocyte and may be an important way for cells to adapt to increased mechanical forces.
3. Ideology at the crossroads of theory
Authors: Freeden Michael
Published: September 2013

Why did ideology come to stay as a category of political and philosophical analysis? ‘Ideology at the crossroads of theory’ shows how the illuminating ideas of a few theorists were sustained by concrete political developments. The advent of mass politics in Europe saw the consolidation of traditions of political thought such a liberalism, conservatism, and socialism. These movements and frameworks for political debate began to develop a life of their own, and these political traditions impelled individuals and groups to political action. The philosopher, Wittgenstein, played an important role in the further development of ideology.
4. The struggle over political language
Authors: Freeden Michael
Published: September 2013

Developments in linguistics provided another external source of inspiration for students of ideology. ‘The struggle over political language’ explores the contribution of language to the development of ideology. The meaning of language — in particular the emphasis on grammar and semantics — played a critical role in enabling similar ideologies to be expressed in their own specific terms. Making sense of ideological texts became an increasingly important role for political theorists. From this emerged the four Ps of ideological composition: proximity, priority, permeability, and proportionality. These have provided an important tool for complex comparative analysis of ideologies.
9. Stimuli and responses: seeing and feeling ideology
Authors: Freeden Michael
Published: September 2013

Ideology has been dealt with as it is found in written and spoken languages but in ‘Stimuli and responses: seeing and feeling ideologies’ three further themes are introduced. Firstly, ideology appears in many non-verbal forms. Second, even as textual discourse, ideology includes metaphors and stories that are not directly decodable as political language. Third, ideology concerns not only the rational and the irrational, the cognitive and the unconscious, but the emotional as well. Over the last century, with the advent of film and television, as well as the mass production of art and advertising, the virtual messages of ideology have been conveyed in new forms.
3. Explanation in science
Authors: Okasha Samir
Published: September 2013

What exactly is scientific explanation? ‘Explanation in science’ begins with Carl Hempel's covering law model of explanation, which says that to explain a phenomenon is to show that its occurrence follows deductively from a general law, perhaps supplemented by other laws and/or particular facts, all of which must be true. This model does not deal with symmetry or irrelevance. The covering law model implies that explanation should be a symmetric relation, but in fact it is asymmetric. Also, a good explanation of a phenomenon should contain information that is relevant to the phenomenon's occurrence. Causality-based accounts of scientific explanation and the concepts of reduction and multiple realization are also explained.
3. Party organizations: What do they look like? What do they do?
Authors: Maisel L. Sandy
Published: September 2013

‘Party Organisations: What do they look like? What do they do?’ examines each of those questions and reveals that political party organizations in the US reflect the nation's federal system. The party is organized at each electoral level. The main purpose of the party is to assist their candidates to get into office. The party organization does not define party policy nor do its leaders exercise much authority of those elected under the party label. This is a situation that has changed quite markedly over the last century as changes have taken place in the electoral process.
Global Warming: A Very Short Introduction
Authors: Maslin Mark
Published: September 2013

Global warming is arguably the most critical and controversial issue facing the world in the twenty-first century. Global Warming: A Very Short Introduction provides a concise and accessible explanation of the key topics in the debate: how and why changes are occurring, setting these changes in the context of past global climate change, looking at the predicted impact of climate change, exploring the political controversies of recent years, and explaining the proposed solutions. Recent developments from US policy to the UK Climate Change Bill, and where we now stand with the Kyoto Protocol are described.