bluuebunny/crossref_metadata_2025 huggingface dataset:
OPTICAL AMPLIFIER WITH FLAT-GAIN AND WIDEBAND OPERATION UTILIZING HIGHLY CONCENTRATED ERBIUM-DOPED FIBERS
Authors: HAMIDA B. A. , CHENG X. S. , NAJI A. W. , AHMAD H. , AL-KHATEEB W. , KHAN S. , HARUN S. W.
Published: April 2012

In this paper, we proposed a flat-gain and wide-band erbium doped fiber amplifier (EDFA) using two chirped fiber Bragg grating (CFBG) in serial configuration for double-pass operation. The amplifier consists of two sections of Erbium-doped fiber (EDF) operating in C-band and L-band respectively. A CFBG is used in each section to reflect the amplified signal back to the active area so that the overall gain spectrum can be enhanced and flattened. It is also observed that the gain of the amplifier produces a relatively higher gain with the Bismuth-based EDF (Bi-EDF) in the first stage compared to that of silica-based EDF (Si-EDF), especially in a longer wavelength region. The small signal gain of more than 19 dB is obtained within a wavelength region from 1545 to 1605 nm by the use of Bi-EDF with a small noise figure penalty. With a Si-EDF, the flat gain spectrum is observed within a wavelength region ranging from 1535 nm to 1605 nm with a gain variation of less than 2 dB at input signal of 0 dBm. This shows that the proposed serial double-pass amplifier may find its broad applications in wavelength division multiplexing long-haul systems as well as local optical networks.
SEARCH FOR THE OPTIMAL PARAMETERS OF RELAXING NONLINEARITY TO OBTAIN SELF-TRAPPING OF AN ULTRASHORT PULSE IN A PHOTONIC CRYSTAL
Authors: NOVITSKY D. V.
Published: April 2012

We theoretically study the conditions for realization of trapping of a femtosecond pulse inside a one-dimensional photonic crystal with the relaxing cubic nonlinearity. A number of variants is considered: focusing and defocusing nonlinearities of the layers, a half-linear system, structures with differing values of nonlinearity parameters of periodically alternating layers. The results seem to be useful to make the optimal choice of the system characteristics to obtain self-trapping.
AN INTEGRATED FRAMEWORK FOR THE STUDY OF ORGANIZATIONAL INNOVATION
Authors: ARISS SONNY S. , DEILAMI VAFA SABOORI
Published: April 2012

Despite the many attempts of researchers to integrate the innovation literature, it continues to be fragmented and its results not cumulative. After a thorough review of the literature, this article proposes an integrative framework that reconciles the theories of innovation by having the types of innovation on one dimension and the degrees of innovation on the other dimension to reduce the confusion in the field and further the development of a workable theory of innovation management. The many factors that influence innovation are then identified and categorized along a four-by-four framework to lead to a comprehensive classification that will reduce the ambiguity and inconsistency in the innovation literature. The implications of this framework for future research on innovation as a profitable product or service are addressed.
TRANSFORMING KNOWLEDGE INTO ACTION TO REACH INNOVATION CAPACITY IN HIGH-TECH SMES
Authors: CHEN TE FU
Published: April 2012

The study aims to explore how high-tech small-to-medium-sized enterprises (SMEs) utilize integrative innovation resource strategy to transforming knowledge into action to reach innovation capacity via integrating innovation culture, knowledge management (KM), managing and organizing innovation, to achieve sustained innovation and value creation, and then to reach KM performances. The study uses multidimensional perspectives to construct an integrative innovation model, and through four case studies to examine this model, compares the distinct features between smaller and larger high-tech SMEs in utilizing integrative innovation resource strategy.

The finding indicates predicting whether an innovative action will progress through an organization, and effectively planning the action, requires managers to identify, understand, and analyze all individual and organizational support that might bear on the action. Management and other integrated processes set up support for action that protect the organization's identity.
APPLICATION OF THE PLASTICITY MODELS THAT INVOLVE THREE STRESS INVARIANTS
Authors: ZHANG TINGTING , GAO XIAOSHENG , WEBLER BRYAN A. , COCKERAM BRIAN V. , HAYDEN MATTHEW , GRAHAM STEPHEN M.
Published: April 2012

Increasing experimental evidence shows that the classical J2plasticity theory may not fully describe the plastic response of many materials, including some metallic alloys. In this paper, the effect of stress state on plasticity and the general forms of the yield function and flow potential for isotropic materials are assumed to be functions of the first invariant of the stress tensor (I1) and the second and third invariants of the deviatoric stress tensor (J2and J3). A 5083 aluminum alloy, Nitronic 40 (a stainless steel), and Zircaloy-4 (a zirconium alloy) were tested under tension, compression, torsion, combined torsion–tension and combined torsion–compression at room temperature to demonstrate the applicability of a proposed I1-J2-J3dependent model. The I1-J2-J3dependent plasticity model was implemented in ABAQUS via a user defined subroutine. The model parameters were determined and validated by comparing the numerically predicted and experimentally measured load versus displacement and/or torque versus twist angle curves. The results showed that the proposed model incorporating the I1-J2-J3dependence produced output that matched experimental data more closely than the classical J2plasticity theory for the loading conditions and materials tested.
A SIX-LINK KINEMATIC CHAIN MODEL OF HUMAN BODY USING KANE'S METHOD
Authors: RAMBELY A. S. , FAZROLROZI
Published: April 2012

A biomechanics model of six-link kinematic chain of human body is developed by using Kane's method. The kinematic data comprise of six segments; foot, calf, thigh, trunk, upper arm and forearm, are obtained through data collection of walking, running and jumping using the Vicon Nexus system. The motion capture system uses 12 Vicon MX-3+ cameras and 12 Vicon MX-F40 cameras, two DV (50 Hz) cameras and a force plate (100 Hz). Inverse dynamics approach is used to obtain the unknown value of torques produced by joint segments during walking, running and jumping activities. The results show that the largest value of torques produced occurs at the foot segment.
A NUMERICAL COMPARISON OF LANGRANGE AND KANE'S METHODS OF AN ARM SEGMENT
Authors: RAMBELY AZMIN SHAM , HALIM NORHAFIZA AB. , AHMAD ROKIAH ROZITA
Published: April 2012

A 2-D model of a two-link kinematic chain is developed using two dynamics equations of motion, namely Kane's and Lagrange Methods. The dynamics equations are reduced to first order differential equation and solved using modified Euler and fourth order Runge Kutta to approximate the shoulder and elbow joint angles during a smash performance in badminton. Results showed that Runge-Kutta produced a better and exact approximation than that of modified Euler and both dynamic equations produced better absolute errors.
MODELING POLIO DATA USING THE FIRST ORDER NON-NEGATIVE INTEGER-VALUED AUTOREGRESSIVE, INAR(1), MODEL
Authors: VAZIFEDAN TURAJ , SHITAN MAHENDRAN
Published: April 2012

Time series data may consists of counts, such as the number of road accidents, the number of patients in a certain hospital, the number of customers waiting for service at a certain time and etc. When the value of the observations are large it is usual to use Gaussian Autoregressive Moving Average (ARMA) process to model the time series. However if the observed counts are small, it is not appropriate to use ARMA process to model the observed phenomenon. In such cases we need to model the time series data by using Non-Negative Integer valued Autoregressive (INAR) process. The modeling of counts data is based on the binomial thinning operator. In this paper we illustrate the modeling of counts data using the monthly number of Poliomyelitis data in United States between January 1970 until December 1983. We applied the AR(1), Poisson regression model and INAR(1) model and the suitability of these models were assessed by using the Index of Agreement(I.A.). We found that INAR(1) model is more appropriate in the sense it had a better I.A. and it is natural since the data are counts.
PROBABILITY MODELS FOR THE DISTRIBUTION OF COPEPODS IN DIFFERENT COASTAL ECOSYSTEMS ALONG THE STRAITS OF MALACCA
Authors: MATIAS-PERALTA HAZEL MONICA , GHODSI ALIREZA , SHITAN MAHENDRAN , YUSOFF FATIMAH MD.
Published: April 2012

Copepods are the most abundant microcrustaceans in the marine waters and are the major food resource for many commercial fish species. In addition, changes in the distribution and population composition of copepods may also serve as an indicator of global climate changes. Therefore, it is important to model the copepod distribution in different ecosystems. Copepod samples were collected from three different ecosystems (seagrass area, cage aquaculture area and coastal waters off shrimp aquaculture farm) along the coastal waters of the Malacca Straits over a one year period. In this study the major statistical analysis consisted of fitting different probability models. This paper highlights the fitting of probability distributions and discusses the adequateness of the fitted models. The usefulness of these fitted models would enable one to make probability statements about the distribution of copepods in three different ecosystems.
STUDY OF STOCHASTIC SYSTEMS FOR EPIDEMIC DISEASE MODELS
Authors: CHAHARBORJ SARKHOSH SEDDIGHI , MOHD RIZAM A. B. , FUDZIAH I.
Published: April 2012

As we know there are two kind of systems in modeling epidemic disease, deterministic systems and stochastic systems. This two systems relate to deterministic and stochastic epidemic disease models, respectively. Almost we use deterministic model for big population size and stochastic model for small population size. To use stochastic models for epidemic disease models, can obtain good results with less error. Study and solving of full stochastic models has not been yet investigated so more. In this article we use the homotopy analysis method to solve the full stochastic susceptible-infective epidemic disease model in disease-free equilibrium point.
LOADING CONTAINERS WITH ANTS
Authors: YAP CHING NEI , LEE LAI SOON , MAJID ZANARIAH ABDUL , SEOW HSIN VONN
Published: April 2012

Loading containers is like loading a subset of given three-dimensional rectangular boxes of different sizes into a three-dimensional rectangular container of fixed dimensions in order to achieve optimal space utilization. In this paper, Ant Colony Optimization (ACO) with its probabilistic decision rule is used to construct towers of boxes and to arrange them into the container. Some initial computational results on benchmark data set will be presented.
THE EFFECT OF NETWORK PARAMETERS ON PI-SIGMA NEURAL NETWORK FOR TEMPERATURE FORECASTING
Authors: HUSAINI NOOR AIDA , GHAZALI ROZAIDA , NAWI NAZRI MOHD , ISMAIL LOKMAN HAKIM
Published: April 2012

In this paper, we present the effect of network parameters to forecast temperature of a suburban area in Batu Pahat, Johor. The common ways of predicting the temperature using Neural Network has been applied for most meteorological parameters. However, researchers frequently neglected the network parameters which might affect the Neural Network's performance. Therefore, this study tends to explore the effect of network parameters by using Pi Sigma Neural Network (PSNN) with backpropagation algorithm. The network's performance is evaluated using the historical dataset of temperature in Batu Pahat for one step-ahead and benchmarked against Multilayer Perceptron (MLP) for comparison. We found out that, network parameters have significantly affected the performance of PSNN for temperature forecasting. Towards the end of this paper, we concluded the best forecasting model to predict the temperature based on the comparison of our study.
NATURE-INSPIRED COGNITIVE EVOLUTION TO PLAY MS. PAC-MAN
Authors: TAN TSE GUAN , TEO JASON , ANTHONY PATRICIA
Published: April 2012

Recent developments in nature-inspired computation have heightened the need for research into the three main areas of scientific, engineering and industrial applications. Some approaches have reported that it is able to solve dynamic problems and very useful for improving the performance of various complex systems. So far however, there has been little discussion about the effectiveness of the application of these models to computer and video games in particular. The focus of this research is to explore the hybridization of nature-inspired computation methods for optimization of neural network-based cognition in video games, in this case the combination of a neural network with an evolutionary algorithm. In essence, a neural network is an attempt to mimic the extremely complex human brain system, which is building an artificial brain that is able to self-learn intelligently. On the other hand, an evolutionary algorithm is to simulate the biological evolutionary processes that evolve potential solutions in order to solve the problems or tasks by applying the genetic operators such as crossover, mutation and selection into the solutions. This paper investigates the abilities of Evolution Strategies (ES) to evolve feed-forward artificial neural network's internal parameters (i.e. weight and bias values) for automatically generating Ms. Pac-man controllers. The main objective of this game is to clear a maze of dots while avoiding the ghosts and to achieve the highest possible score. The experimental results show that an ES-based system can be successfully applied to automatically generate artificial intelligence for a complex, dynamic and highly stochastic video game environment.
ROUTING VEHICLES WITH ANTS
Authors: TAN WEN FANG , LEE LAI SOON , MAJID ZANARIAH ABDUL , SEOW HSIN VONN
Published: April 2012

Routing vehicles involve the design of an optimal set of routes for a fleet of vehicles to serve a number of customers with known demands. This research develops an Ant Colony Optimization for the vehicle routing with one central depot and identical vehicles. The procedure simulates the behavior of real ants that always find the shortest path between their nest and a food source through a form of communication, pheromone trail. Finally, preliminary results on the learning of the algorithm testing on benchmark data set will be presented in this paper.
CRITERIA OF COMPACTNESS IN Lp - SPACES
Authors: CHILIN V.I. , RAKHIMOV B.A.
Published: April 2012

The problems of mathematical biology, as a rule, are formulated in terms of independent and depended (unknown) variables (functions), and operators (mostly differential operators). These variables belong to some spaces and operators acting in these spaces. Both, unknown variables and operators, follow the main rules of these spaces as metrics, topology and etc. In applications a solution of the problem will be constructed by approximation methods based on metrics/topology of the space. In this convergence of the constructed approximations essentially depends on compactness.
Staged, Open, No-Ischemia Nephron-Sparing Surgery for Bilateral-Multiple Kidney Tumors in a Patient with Birt-Hogg-Dubé Syndrome
Authors: Tefekli Ahmet , Akkaya Ayşe Deniz , Peker Kamil , Gümüş Terman , Vural Metin , Cezayirli Fatin , Musaoglu Ahmet , Esen Tarık
Published: April 2012

Hereditary kidney cancer patients with bilateral multiple kidney tumors represent challenges in the era of rapidly growing minimal invasive treatment techniques. Birt-Hogg-Dubé Syndrome (BHDS) is an autosomal dominant genodermatosis characterized by a triad of benign skin tumors (fibrofolliculomas, trichodiscomas, acrochordons) together with an increased risk of developing malignant renal tumors and pulmonary disease such as pneumothoraces and multiple lung cysts. The morbidity and mortality of the affected patients is determined by the presence of the kidney tumors, which tend to be multifocal and bilateral, as observed in other hereditary kidney cancer syndromes like von Hippel-Lindau disease, familial leiomyomatosis, and hereditary papillary renal cell carcinoma. Herein, a patient with BHDS, presenting with synchronous bilateral multiple kidney tumors, is reported. The report describes the management of kidney tumors with two-stage open nephron-sparing surgery in which the nonvascular clamping technique was utilized.
Effects of Histamine H4 Receptor Ligands in a Mouse Model of Gastric Ulceration
Authors: Adami Maristella , Pozzoli Cristina , Menozzi Alessandro , Bertini Simone , Passeri Benedetta , Cantoni Anna Maria , Smits Rogier , de Esch Iwan , Leurs Rob , Coruzzi Gabriella
Published: April 2012

Aim: In the present study we examined whether histamine H4 receptors (H4Rs) have a role in gastric ulcerogenesis using a mouse model of gastric damage. Methods: The H4R antagonist JNJ7777120 and the H4R agonists VUF8430 and VUF10460 were investigated in fasted CD-1 mice against the ulcerogenic effect induced by co-administration of indomethacin (IND, 30 mg/kg s.c.) and bethanechol (BET, 5 mg/kg i.p.). Both macroscopic and histologic lesions were examined. Strain-related differences were investigated by testing JNJ7777120 also in NMRI, BALB/c and C57BL/6J mice. Results: Neither JNJ7777120 nor the H4R agonists displayed effects in the normal stomach at any dose tested (10 and 30 mg/kg s.c.). As expected, IND+BET provoked several lesions in the fundic mucosa, which were significantly reduced by JNJ7777120 (10 and 30 mg/kg s.c.). The gastroprotective effect of JNJ7777120 (10 and 30 mg/kg s.c.) was observed in CD-1, NMRI and BALB/c, but not in C57BL/6J, mice. In CD-1 mice, the H4R agonists VUF8430 and VUF10460 (both at 10 and 30 mg/kg s.c.) did not modify the damage induced by IND+BET, however VUF8430 (10 mg/kg s.c.) prevented the gastroprotection induced by JNJ7777120 (10 mg/kg s.c.). Conclusions: Data obtained with selective ligands suggest that the H4R may have a role in mouse gastric ulcerogenesis. If confirmed in humans, these data would emphasize the potential advantage of H4R blockers as gastrosparing anti-inflammatory drugs. The lack of effects of JNJ7777120 in C57BL/6J mice has to be carefully considered in the pharmacological characterization of H4R functions and/or new selective ligands.
Human Energy Budget Modeling in Urban Parks in Toronto and Applications to Emergency Heat Stress Preparedness
Authors: Vanos Jennifer K. , Warland Jon S. , Gillespie Terry J. , Slater Graham A. , Brown Robert D. , Kenny Natasha A.
Published: April 2012

The current study tests applications of the Comfort Formula (COMFA) energy budget model by assessing the moderating effects of urban parks in contrast to streets, and it also looks at the influence of park types (“open” or “treed”). Exploration into energy budget modeling is based on empirical meteorological data collected in Toronto, Ontario, Canada, on fair-weather days plus the effects of a heat wave and climate change, at various metabolic activity levels. Park cooling temperature intensities ranged from 3.9° to 6.0°C, yet human energy budgets were more closely correlated to incoming solar radiation than to air temperature. A strong linear dependence was found, with absorbed radiation (correlation coefficient squared r2 = 0.858) explaining the largest fraction of energy budget output. Hence, although the four parks that were examined are classified as urban green space, the distinctive treed areas showed a greater budget decrease than did open park areas (−25.5 W m−2). The greatest difference in budget decrease was found when modeling the highest metabolic rate, giving −20 W m−2 for “whole park,” −32 W m−2 for treed sections, and −3 W m−2 in open park areas. These results are intuitive within energy budget modeling and indicate that blocking radiant energy is a vital aspect in lowering high budgets under the conditions tested. Strong empirical support was provided through successful prediction of emergency-response calls during a heat wave in Toronto (5–7 July 2010) and surrounding days. Calls were found to be significantly dependent on the energy budget estimations (r2 = 0.860). There is great potential for outdoor energy budget modeling as a meaningful guide to heat stress forecasting, future research, and application in bioclimatic urban design for improving thermal comfort.
Histopathological and Postoperative Behavioral Comparison of Rodent Oral Tongue Resection
Authors: Shires Courtney B. , Saputra Jennifer M. , King Lauren , Thompson Jerome W. , Heck Detlef H. , Sebelik Merry E. , Boughter John D.
Published: April 2012

Objective

To compare operative time and hemostasis of fiber‐enabled CO2 laser (FECL) energy to that of the electrocautery (EC) technique for oral tongue resection, to compare return to oral intake and preoperative weight after FECL and EC resection, and to compare histologic changes in adjacent tissue after FECL and EC resection.

Study Design

Prospective animal study.

Setting

Research laboratory.

Subjects and Methods

The CO2 laser fiber and the Bovie cautery were each used to resect the anterior tongue in 15 adult rats. Fixative perfusion and killing were performed on postoperative day 0 (n = 10), 3 (n = 10), or 7 (n = 10). Body weight, food intake, and water intake were recorded daily for 3‐ and 7‐day survival rats. After preparation for histologic analysis, the tongue tissue was graded with a mucosal wound‐healing scale (MWHS).

Results

A higher incidence of intraoperative bleeding and shorter operative times were noted in the EC group. No statistically significant difference in postoperative food or water intake between the EC and FECL groups was noted. The FECL group returned to baseline weight by postoperative day 6. MWHS scores were lower in the EC group by postoperative day 3 and lower in the FECL group by postoperative day 7.

Conclusions

Both EC and FECL are effective for resection of the tongue in rats. EC has the advantage of shorter operative time and lower MWHS scores by postoperative day 3; FECL has the advantages of less intraoperative bleeding, faster return to baseline body weight, and lower MWHS score by postoperative day 7.
Mesial Temporal Sclerosis in a Cohort of Children With SCN1A Gene Mutation
Authors: Van Poppel Katherine , Patay Zoltan , Roberts Donna , Clarke Dave F. , McGregor Amy , Perkins F. Frederick , Wheless James W.
Published: April 2012

Mesial temporal sclerosis is uncommon in childhood but has been associated with febrile status epilepticus. SCN1A gene mutations are linked to multiple epilepsy syndromes with patients frequently presenting with prolonged febrile seizures. After observing mesial temporal sclerosis in a child with SCN1A gene mutation, we retrospectively reviewed magnetic resonance imaging (MRI) findings in all patients with SCN1A gene mutation identified between 2005 and 2010. We identified 20 patients with SCN1A mutations. Six patients had evidence of definite mesial temporal sclerosis with 2 patients having bilateral abnormalities. Another 4 patients were defined as having possible mesial temporal sclerosis. This patient group revealed that 50% had findings consistent with definite or possible mesial temporal sclerosis and many did not have a history of prolonged febrile seizures. We conclude that mesial temporal sclerosis is a common finding in children with SCN1A mutations. Many of these children will have Dravet syndrome but not all.
Mumps Virus–Associated Acute Encephalopathy
Authors: Watanabe Masahiro , Suyama Kazuhide , Hashimoto Koichi , Sato Masatoki , Ohara Shinichiro , Abe Yusaku , Kawasaki Yukihiko , Yamaguchi Seiji , Saijo Masayuki , Hosoya Mitsuaki
Published: April 2012

We describe a fatal case of mumps virus–associated acute encephalopathy. In terms of the clinical course and cytokine as well as chemokine profiles, the pathogenesis in our case was different from that of mumps meningoencephalitis but was similar to that of influenza virus–associated acute encephalopathy.
Platelet Counts and Coagulation Tests Prior to Neuraxial Anesthesia in Patients With Preeclampsia
Authors: Sultan Pervez , Butwick Alexander
Published: April 2012

This retrospective, descriptive study aimed to assess hematologic testing practices in 100 patients with preeclampsia undergoing neuraxial blockade (NB). Prior to NB, platelet (PLT) count was performed in 61 (98%) of 62 women in labor and in 37 (97%) of 38 women undergoing cesarean delivery (CD). No patients had a pre-NB PLT count <70 × 109/L. Pre-NB tests for prothrombin time (PT) and activated partial thromboplastin time (APTT) were less common and varied among laboring patients (15 [24%] of 62) and patients prior to CD (18 [47%] of 38). Prior to NB, PT and APTT values were within normal limits in all patients. The time intervals between laboratory testing and NB ranged from <2 to >12 hours. The lack of consistency in pre-NB coagulation testing and the variable time intervals between laboratory tests and NB may be due to a lack of consensus among anesthesiologists for determining “safe” hemostatic conditions for NB placement in patients with preeclampsia.
“From High Skill to High School”
Authors: Slade Bonnie
Published: April 2012

From High Skill to High School details the experiences of immigrant professionals in an adult education employment program. This research reveals that immigrants with graduate degrees and years of international work experience are put through curriculum designed for adolescents with limited work experience, and collectively perform more than 1.92 million hours of unpaid work annually in both community-based organizations and for-profit companies. In this mixed-method research project combining institutional ethnography with Reader’s Theatre, the Reader’s Theatre serves as a powerful medium to detail the process of deskilling. While Reader’s Theatre complements the institutional ethnographic analysis by vividly bringing the data to life, representational issues emerge in combining the two approaches. For the playwright, the Reader’s Theatre may seem overly detailed and less aesthetically pleasing. These details, however, are necessary to the analysis as they are vital clues to the social organization of power for the institutional ethnographer.
Multiple sclerosis and progressive resistance training: a systematic review
Authors: Kjølhede T , Vissing K , Dalgas U
Published: April 2012

Recently progressive resistance training (PRT) has been recognised as an effective tool in the rehabilitation of persons with multiple sclerosis (MS). The objective of this study was to systematically review the literature of PRT studies for persons with MS. A comprehensive literature search (PubMed, SveMed+, Embase, Cochrane, PEDro, SPORTDiscus and Bibliotek.dk) was conducted. Identified papers were rated according to the PEDro-scale. Sixteen studies were included and scored between 3 and 8 of 11 total points on the PEDro-scale, showing a general lack of blinding. Strong evidence regarding the beneficial effect of PRT on muscle strength was observed. Regarding functional capacity, balance and self-reported measures (fatigue, quality of life and mood) evidence is less strong, but the tendency is overall positive. Indications of an effect on underlying mechanisms such as muscle morphological changes, neural adaptations and cytokines also exist, but the studies investigating these aspects are few and inconclusive. PRT has a positive effect on muscle strength for persons with MS. Heterogeneous results exist regarding the effect on functional capacity and self-reported measures probably because of differences in training protocols, samples sizes, type and severity of MS. The area of underlying mechanisms deserves more attention in future research.
Archiving digital narrative: Some issues
Authors: Abba Tom
Published: April 2012

The complexities of archiving digital content, particularly those story forms reliant on multiple platforms, highlights technical, cultural and curatorial issues that remain difficult to reconcile coherently. Seeking to frame the issues within this special Debates section, this essay outlines issues facing the field of digital storytelling; examining narrative form, instantiation and subsequent archival.
Postcards as representation of a destination image: The case of Berlin
Authors: Milman Ady
Published: April 2012

The study adopted a qualitative approach to assess the role of postcards in representing a destination image. Twenty-five postcard racks were sampled in a variety of retail outlets in Berlin, using an observation and photography of the postcards. The 150 postcards sampled were analyzed and sorted according to the pictorial content and other iconic symbols featured on the postcards using certain photographic typologies employed in previous research. The findings revealed that unlike many other large metropolitan cities, Berlin was distinctively represented in its postcards. The analysis concluded that the postcards lacked human portrayal and featured a limited sample of its cultural and heritage attractions. Instead, the majority of the postcards featured Cold War themes, as well as generic icons and legendary mascots of the city. The lack of a focus representation of contemporary Berlin in tourists’ postcards may be explained by Berlin’s historical, economic, political, and social background. Recommendations for developing more pertinent images of the tourist experiences to be featured on postcards are discussed.
The protective effects of ginsenoside Rg1 against hypertension target-organ damage in spontaneously hypertensive rats
Authors: Chen Hui , Yin Jun , Deng Yanpin , Yang Min , Xu Lingling , Teng Fukang , Li Defang , Cheng Yufan , Liu Sha , Wang Dong , Zhang Tingting , Wu Wanying , Liu Xuan , Guan Shuhong , Jiang Baohong , Guo Dean
Published: April 2012

Background

Although a number of medicines are available for the management of hypertension, the organ damage induced by hypertension is not resolved. The aim of this study was to investigate the protection of ginsenoside Rg1 (Rg1) against vascular remodeling and organ damage in spontaneously hypertensive rats (SHR).

Methods

Male SHR were treated with 5, 10 or 20 mg/kg Rg1 through intraperitoneal injection per day for 1 month. SHR or Wistar-Kyoto rats (WKY) receiving vehicle (saline) was used as control. Blood pressure detection and pathological stain, transmission electron microscope, immunohistochemical assay were used to elucidate the protection of Rg1.

Results

Blood pressures were not different between control SHR rats and Rg1 treated SHR rats, but Rg1 improved the aortic outward remodeling by lowering the lumen diameter and reducing the media thickness according the histopathological and ultrastructural detections. Rg1 also protected the retinal vessels against inward remodeling detected by immunohistochemical assay. Furthermore, Rg1 attenuated the target heart and kidney damage with improvement on cardiac and glomerular structure.

Conclusions

These results suggested that Rg1 held beneficial effects on vascular structure and further protected against the organ-damage induced by hypertension. These findings also paved a novel and promising approach to the treatment of hypertensive complications.
Outcomes of prolonged mechanic ventilation: a discrimination model based on longitudinal health insurance and death certificate data
Authors: Lu Hsin-Ming , Chen Likwang , Wang Jung-Der , Hung Mei-Chuan , Lin Ming-Shian , Yan Yuan-Horng , Chen Cheng-Ren , Fan Po-Sheng , Huang Lynn Chu , Kuo Ken N
Published: April 2012

Background

This study investigated prognosis among patients under prolonged mechanical ventilation (PMV) through exploring the following issues: (1) post-PMV survival rates, (2) factors associated with survival after PMV, and (3) the number of days alive free of hospital stays requiring mechanical ventilation (MV) care after PMV.

Methods

This is a retrospective cohort study based on secondary analysis of prospectively collected data in the national health insurance system and governmental data on death registry in Taiwan. It used data for a nationally representative sample of 25,482 patients becoming under PMV (> = 21 days) during 1998-2003. We calculated survival rates for the 4 years after PMV, and adopted logistic regression to construct prediction models for 3-month, 6-month, 1-year, and 2-year survival, with data of 1998-2002 for model estimation and the 2003 data for examination of model performance. We estimated the number of days alive free of hospital stays requiring MV care in the immediate 4-year period after PMV, and contrasted patients who had low survival probability with all PMV patients.

Results

Among these patients, the 3-month survival rate was 51.4%, and the 1-year survival rate was 31.9%. Common health conditions with significant associations with poor survival included neoplasm, acute and unspecific renal failure, chronic renal failure, non-alcoholic liver disease, shock and septicaemia (odd ratio < 0.7, p < 0.05). During a 4-year follow-up period for patients of year 2003, the mean number of days free of hospital stays requiring MV was 66.0 in those with a predicted 6-month survival rate < 10%, and 111.3 in those with a predicted 2-year survival rate < 10%. In contrast, the mean number of days was 256.9 in the whole sample of patients in 2003.

Conclusions

Neoplasm, acute and unspecific renal failure, shock, chronic renal failure, septicemia, and non-alcoholic liver disease are significantly associated with lower survival among PMV patients. Patients with anticipated death in a near future tend to spend most of the rest of their life staying in hospital using MV services. This calls for further research into assessing PMV care need among patients at different prognosis stages of diseases listed above.
Visualisation of cerebrospinal fluid flow patterns in albino Xenopus larvae in vivo
Authors: Mogi Kazue , Adachi Takeshi , Izumi Susumu , Toyoizumi Ryuji
Published: April 2012

Background

It has long been known that cerebrospinal fluid (CSF), its composition and flow, play an important part in normal brain development, and ependymal cell ciliary beating as a possible driver of CSF flow has previously been studied in mammalian fetuses in vitro. Lower vertebrate animals are potential models for analysis of CSF flow during development because they are oviparous. Albino Xenopus laevis larvae are nearly transparent and have a straight, translucent brain that facilitates the observation of fluid flow within the ventricles. The aim of these experiments was to study CSF flow and circulation in vivo in the developing brain of living embryos, larvae and tadpoles of Xenopus laevis using a microinjection technique.

Methods

The development of Xenopus larval brain ventricles and the patterns of CSF flow were visualised after injection of quantum dot nanocrystals and polystyrene beads (3.1 or 5.8 μm in diameter) into the fourth cerebral ventricle at embryonic/larval stages 30-53.

Results

The fluorescent nanocrystals showed the normal development of the cerebral ventricles from embryonic/larval stages 38 to 53. The polystyrene beads injected into stage 47-49 larvae revealed three CSF flow patterns, left-handed, right-handed and non-biased, in movement of the beads into the third ventricle from the cerebral aqueduct (aqueduct of Sylvius). In the lateral ventricles, anterior to the third ventricle, CSF flow moved anteriorly along the outer wall of the ventricle to the inner wall and then posteriorly, creating a semicircle. In the cerebral aqueduct, connecting the third and fourth cerebral ventricles, CSF flow moved rostrally in the dorsal region and caudally in the ventral region. Also in the fourth ventricle, clear dorso-ventral differences in fluid flow pattern were observed.

Conclusions

This is the first visualisation of the orchestrated CSF flow pattern in developing vertebrates using a live animal imaging approach. CSF flow in Xenopus albino larvae showed a largely consistent pattern, with the exception of individual differences in left-right asymmetrical flow in the third ventricle.
Construction of a novel Pichia pastoris strain for production of xanthophylls
Authors: Araya-Garay José Miguel , Ageitos José M , Vallejo Juan A , Veiga-Crespo Patricia , Sánchez-Pérez Angeles , Villa Tomás G
Published: April 2012

In this study, we used the yeast carotenogenic producer Pichia pastoris Pp-EBIL strain, which has been metabolically engineered, by heterologously expressing β-carotene-pathway enzymes to produce β-carotene, as a vessel for recombinant astaxanthin expression. For this purpose, we designed new P. pastoris recombinant-strains harboring astaxanthin-encoding genes from carotenogenic microorganism, and thus capable of producing xanthophyllic compounds. We designed and constructed a plasmid (pGAPZA-WZ) containing both the β-carotene ketolase (crtW) and β-carotene hydroxylase (crtZ) genes from Agrobacterium aurantiacum, under the control of the GAP promoter and containing an AOX-1 terminator. The plasmid was then integrated into the P. pastoris Pp-EBIL strain genomic DNA, producing clone Pp-EBILWZ. The recombinant P. pastoris (Pp-EBILWZ) cells exhibited a strong reddish carotenoid coloration and were confirmed, by HPLC, to produce not only the previous described carotenoids lycopene and β-carotene, but also de novo synthesized astaxanthin.
The determination of nest depth in founding queens of leaf-cutting ants (Atta vollenweideri): idiothetic and temporal control
Authors: Fröhle Kerstin , Roces Flavio
Published: April 2012

Leaf-cutting ant queens excavate a founding nest consisting of a vertical tunnel and a final horizontal chamber. Nest foundation is very time consuming, and colony success depends on the excavated depth. Although shallow nests may be energetically cheaper to dig, queens may be more exposed to the changing environment. Deeper chambers, in contrast, may be climatically more stable, but are more expensive to dig. We investigated the mechanisms underlying the control of nest depth in queens of the leaf-cutting ant Atta vollenweideri. We focused on the use of internal information for the control of nest depth, and therefore maintained the soil and environmental conditions invariant during the different laboratory experiments. We compared the tunnel lengths excavated by queens that were able to complete their nests earlier, faster or slower than under standard conditions. An earlier and faster nest completion was obtained by offering queens either pre-excavated tunnels of different lengths, soils at different temperatures, or soft sandy soils. A slower nest excavation was induced by offering queens harder dry soils, and by delaying the start of digging several days after the nuptial flight. Results indicate that the determination of nest depth was a regulated process involving the use of internal references: queens excavated their tunnels either until a particular depth was reached or for some predetermined length of time. Queens appear to monitor their movements while walking up und down the tunnel, and to compare this sensory information with a motor command that represents a preset tunnel length to be excavated before switching to chamber digging. In addition to this form of idiothetic control, results indicate that the elapsed digging time also feeds back onto the control system. It is argued that the determination of nest depth, i.e. the transition from tunnel to chamber digging, is initiated either after a preset tunnel length is reached, or as soon as a maximal time interval has elapsed, irrespective of the excavated tunnel length. A control system using both idiothetic and temporal information, as demonstrated in the present study, allows queens to flexibly react to different soil conditions, and therefore avoid excessive time and energy investments. Possible mechanisms underlying the control of chamber size are also discussed.
INT6 interacts with MIF4GD/SLIP1 and is necessary for efficient histone mRNA translation
Authors: Neusiedler Julia , Mocquet Vincent , Limousin Taran , Ohlmann Theophile , Morris Christelle , Jalinot Pierre
Published: April 2012

The INT6/EIF3E protein has been implicated in mouse and human breast carcinogenesis. This subunit of the eIF3 translation initiation factor that includes a PCI domain exhibits specific features such as presence in the nucleus and ability to interact with other important cellular protein complexes like the 26S proteasome and the COP9 signalosome. It has been previously shown that INT6 was not essential for bulk translation, and this protein is considered to regulate expression of specific mRNAs. Based on the results of a two-hybrid screen performed with INT6 as bait, we characterize in this article the MIF4GD/SLIP1 protein as an interactor of this eIF3 subunit. MIF4GD was previously shown to associate with SLBP, which binds the stem–loop located at the 3′ end of the histone mRNAs, and to be necessary for efficient translation of these cell cycle–regulated mRNAs that lack a poly(A) tail. In line with the interaction of both proteins, we show using the RNA interference approach that INT6 is also essential to S-phase histone mRNA translation. This was observed by analyzing expression of endogenous histones and by testing heterologous constructs placing the luciferase reporter gene under the control of the stem–loop element of various histone genes. With such a reporter plasmid, silencing and overexpression of INT6 exerted opposite effects. In agreement with these results, INT6 and MIF4GD were observed to colocalize in cytoplasmic foci. We conclude from these data that INT6, by establishing interactions with MIF4GD and SLBP, plays an important role in translation of poly(A) minus histone mRNAs.
Introduction to the Special Issue on Analytics in Sports, Part I: General Sports Applications
Authors: Fry Michael J. , Ohlmann Jeffrey W.
Published: April 2012

Sports is a rapidly growing application area for analytics. The use of analytics is pervasive in the professional sports community as evidenced by the increased role for those practicing sports analytics in front-office management and coaching. Part I of this Special Issue on Analytics in Sports is devoted to the application of a variety of methodologies to a broad range of sports. The papers analyze golf, hockey, baseball, motorcycle racing, and college football. The methodologies employed draw from many areas of analytics including optimization, probabilistic modeling, and choice models.
Cervical Spinal Erythropoietin Induces Phrenic Motor Facilitation via Extracellular Signal-Regulated Protein Kinase and Akt Signaling
Authors: Dale Erica A. , Satriotomo Irawan , Mitchell Gordon S.
Published: April 2012

Erythropoietin (EPO) is typically known for its role in erythropoiesis but is also a potent neurotrophic/neuroprotective factor for spinal motor neurons. Another trophic factor regulated by hypoxia-inducible factor-1, vascular endothelial growth factor (VEGF), signals via ERK and Akt activation to elicit long-lasting phrenic motor facilitation (pMF). Because EPO also signals via ERK and Akt activation, we tested the hypothesis that EPO elicits similar pMF. Using retrograde labeling and immunohistochemical techniques, we demonstrate in adult, male, Sprague Dawley rats that EPO and its receptor, EPO-R, are expressed in identified phrenic motor neurons. Intrathecal EPO at C4 elicits long-lasting pMF; integrated phrenic nerve burst amplitude increased >90 min after injection (63 ± 12% baseline 90 min after injection;p< 0.001). EPO increased phosphorylation (and presumed activation) of ERK (1.6-fold vs controls;p< 0.05) in phrenic motor neurons; EPO also increased pAkt (1.6-fold vs controls;p< 0.05). EPO-induced pMF was abolished by the MEK/ERK inhibitor U0126 [1,4-diamino-2,3-dicyano-1,4-bis(o-aminophenylmercapto)butadiene] and the phosphatidylinositol 3-kinase/Akt inhibitor LY294002 [2-(4-morpholinyl)-8-phenyl-1(4H)-benzopyran-4-one], demonstrating that ERK MAP kinases and Akt are both required for EPO-induced pMF. Pretreatment with U0126 and LY294002 decreased both pERK and pAkt in phrenic motor neurons (p< 0.05), indicating a complex interaction between these kinases. We conclude that EPO elicits spinal plasticity in respiratory motor control. Because EPO expression is hypoxia sensitive, it may play a role in respiratory plasticity in conditions of prolonged or recurrent low oxygen.
Evidence for a Fragile X Mental Retardation Protein-Mediated Translational Switch in Metabotropic Glutamate Receptor-Triggered Arc Translation and Long-Term Depression
Authors: Niere Farr , Wilkerson Julia R. , Huber Kimberly M.
Published: April 2012

Group 1 metabotropic glutamate receptor (mGluR)-stimulated protein synthesis and long-term synaptic depression (mGluR-LTD) are altered in the mouse model of fragile X syndrome,Fmr1knock-out (KO) mice.Fmr1encodes fragile X mental retardation protein (FMRP), a dendritic RNA binding protein that functions, in part, as a translational suppressor. It is unknown whether and how FMRP acutely regulates LTD and/or the rapid synthesis of new proteins required for LTD, such as the activity-regulated cytoskeletal-associated protein (Arc). The protein phosphatase PP2A dephosphorylates FMRP, which contributes to translational activation of some target mRNAs. Here, we report that PP2A and dephosphorylation of FMRP at S500 are required for an mGluR-induced, rapid (5 min) increase in dendritic Arc protein and LTD in rat and mouse hippocampal neurons. InFmr1KO neurons, basal, dendritic Arc protein levels and mGluR-LTD are enhanced, but mGluR-triggered Arc synthesis is absent. Lentiviral-mediated expression of wild-type FMRP inFmr1KO neurons suppresses basal dendritic Arc levels and mGluR-LTD, and restores rapid mGluR-triggered Arc synthesis. A phosphomimic of FMRP (S500D) suppresses steady-state dendritic Arc levels but does not rescue mGluR-induced Arc synthesis. A dephosphomimic of FMRP (S500A) neither suppresses dendritic Arc nor supports mGluR-induced Arc synthesis. Accordingly, S500D-FMRP expression inFmr1KO neurons suppresses mGluR-LTD, whereas S500A-FMRP has no effect. These data support a model in which phosphorylated FMRP functions to suppress steady-state translation of Arc and LTD. Upon mGluR activation of PP2A, FMRP is rapidly dephosphorylated, which contributes to rapid new synthesis of Arc and mGluR-LTD.
A Reversible Early Oxidized Redox State That Precedes Macromolecular ROS Damage in Aging Nontransgenic and 3xTg-AD Mouse Neurons
Authors: Ghosh Debolina , LeVault Kelsey R. , Barnett Aaron J. , Brewer Gregory J.
Published: April 2012

The brain depends on redox electrons from nicotinamide adenine dinucleotide (reduced form; NADH) to produce ATP and oxyradicals (reactive oxygen species [ROS]). Because ROS damage and mitochondrial dysregulation are prominent in aging and Alzheimer's disease (AD) and their relationship to the redox state is unclear, we wanted to know whether an oxidative redox shift precedes these markers and leads to macromolecular damage in a mouse model of AD. We used the 3xTg-AD mouse model, which displays cognitive deficits beginning at 4 months. Hippocampal/cortical neurons were isolated across the age span and cultured in common nutrients to control for possible hormonal and vascular differences. We found an increase of NAD(P)H levels and redox state in nontransgenic (non-Tg) neurons until middle age, followed by a decline in old age. The 3xTg-AD neurons maintained much lower resting NAD(P)H and redox states after 4 months, but the NADH regenerating capacity continuously declined with age beginning at 2 months. These redox characteristics were partially reversible with nicotinamide, a biosynthetic precursor of NAD+. Nicotinamide also protected against glutamate excitotoxicity. Compared with non-Tg neurons, 3xTg-AD neurons had more mitochondria/neuron and lower glutathione (GSH) levels that preceded age-related increases in ROS levels. These GSH deficits were again reversible with nicotinamide in 3xTg-AD neurons. Surprisingly, low macromolecular ROS damage was only elevated after 4 months in the 3xTg-AD neurons if antioxidants were removed. The present data suggest that a more oxidized redox state and a lower antioxidant GSH defense can be dissociated from neuronal ROS damage, changes that precede the onset of cognitive deficits in the 3xTg-AD model.