bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and Fabrication of Vertically-Integrated CMOS Image Sensors
Authors: Skorka Orit , Joseph Dileepan
Published: April 2011

Technologies to fabricate integrated circuits (IC) with 3D structures are an emerging trend in IC design. They are based on vertical stacking of active components to form heterogeneous microsystems. Electronic image sensors will benefit from these technologies because they allow increased pixel-level data processing and device optimization. This paper covers general principles in the design of vertically-integrated (VI) CMOS image sensors that are fabricated by flip-chip bonding. These sensors are composed of a CMOS die and a photodetector die. As a specific example, the paper presents a VI-CMOS image sensor that was designed at the University of Alberta, and fabricated with the help of CMC Microsystems and Micralyne Inc. To realize prototypes, CMOS dies with logarithmic active pixels were prepared in a commercial process, and photodetector dies with metal-semiconductor-metal devices were prepared in a custom process using hydrogenated amorphous silicon. The paper also describes a digital camera that was developed to test the prototype. In this camera, scenes captured by the image sensor are read using an FPGA board, and sent in real time to a PC over USB for data processing and display. Experimental results show that the VI-CMOS prototype has a higher dynamic range and a lower dark limit than conventional electronic image sensors.
Study on the Context-Aware Middleware for Ubiquitous Greenhouses Using Wireless Sensor Networks
Authors: Hwang Jeonghwang , Yoe Hyun
Published: April 2011

Wireless Sensor Network (WSN) technology is one of the important technologies to implement the ubiquitous society, and it could increase productivity of agricultural and livestock products, and secure transparency of distribution channels if such a WSN technology were successfully applied to the agricultural sector. Middleware, which can connect WSN hardware, applications, and enterprise systems, is required to construct ubiquitous agriculture environment combining WSN technology with agricultural sector applications, but there have been insufficient studies in the field of WSN middleware in the agricultural environment, compared to other industries. This paper proposes a context-aware middleware to efficiently process data collected from ubiquitous greenhouses by applying WSN technology and used to implement combined services through organic connectivity of data. The proposed middleware abstracts heterogeneous sensor nodes to integrate different forms of data, and provides intelligent context-aware, event service, and filtering functions to maximize operability and scalability of the middleware. To evaluate the performance of the middleware, an integrated management system for ubiquitous greenhouses was implemented by applying the proposed middleware to an existing greenhouse, and it was tested by measuring the level of load through CPU usage and the response time for users’ requests when the system is working.
Optimization of Urea-EnFET Based on Ta2O5 Layer with Post Annealing
Authors: Lue Cheng-En , Yu Ting-Chun , Yang Chia-Ming , Pijanowska Dorota G. , Lai Chao-Sung
Published: April 2011

In this study, the urea-enzymatic field effect transistors (EnFETs) were investigated based on pH-ion sensitive field effect transistors (ISFETs) with tantalum pentoxide (Ta2O5) sensing membranes. In addition, a post N2 annealing was used to improve the sensing properties. At first, the pH sensitivity, hysteresis, drift, and light induced drift of the ISFETs were evaluated. After the covalent bonding process and urease immobilization, the urea sensitivity of the EnFETs were also investigated and compared with the conventional Si3N4 sensing layer. The ISFETs and EnFETs with annealed Ta2O5 sensing membranes showed the best responses, including the highest pH sensitivity (56.9 mV/pH, from pH 2 to pH 12) and also corresponded to the highest urea sensitivity (61 mV/pCurea, from 1 mM to 7.5 mM). Besides, the non-ideal factors of pH hysteresis, time drift, and light induced drift of the annealed samples were also lower than the controlled Ta2O5 and Si3N4 sensing membranes.
Caging the Beast: TRIM5α Binding to the HIV-1 Core
Authors: Diaz-Griffero Felipe
Published: April 2011

The potent HIV-1 inhibitor TRIM5α blocks HIV-1 infection by accelerating the uncoating of HIV-1. TRIM5α is known to form higher-order self-association complexes that contribute to the avidity of TRIM5α for the HIV-1 capsid, and are essential to inhibit infection; these higher-order self-association complexes are dependent upon an intact B-box 2 domain. Even though the ability to form higher-order self-association complexes resembles the clathrin triskelion that forms a protein array, or cage, around the endocytic vesicle, evidence for the ability of TRIM5α to assemble a similar type of structure surrounding the HIV-1 core has been lacking. Recent work by Ganser-Pornillos, Chandrasekaran and colleagues has now demonstrated the ability of the restriction factor TRIM5α to “cage” or “net” the HIV-1 core by forming an hexagonal array on the surface of the viral capsid [1]. This hexagonal array is strikingly similar in design to the array formed by the clathrin triskelion on the surface of the clathrin-coated endocytic vesicle. This remarkable finding represents an important advance on our understanding of the restriction factor TRIM5α, and suggests that TRIM5α cages the HIV-1 core in order to terminate infection. The present note discusses the implications of this discovery.
Detection of interaction between biomineralising proteins and calcium carbonate microcrystals
Authors: Rademaker Hanna , Launspach Malte
Published: April 2011

The natural composite nacre is characterised by astonishing mechanical properties, although the main constituent is a brittle mineral shaped as tablets interdispersed by organic layers. To mimic the natural formation process which takes place at ambient conditions an understanding of the mechanism responsible for a defined microstructure of nacre is necessary. Since proteins are assumed to be involved in this mechanism, it is advantageous to identify distinct proteins interacting with minerals from the totality of proteins contained in nacre. Here, we adopted and modified a recently published approach given by Suzuki et al. Suzuki, M.; Saruwatari, K.; Kogure, T.; Yamamoto, Y.; Nishimura, T.; Kato, T.; Nagasawa, H. Science 2009, 325, 1388–1390. doi:10.1126/science.1173793 that gives a hint of specific protein–mineral interactions. Synthesised aragonite or calcite microcrystals were incubated with a protein mixture extracted from nacre of Haliotis laevigata. After incubation the mineral phase was dissolved and investigated for attached proteins. The results give a hint of one protein that seems to bind specifically to aragonite and not to calcite. The presented protocol seems to be suitable to detect mineral binding proteins quickly and therefore can point to proteins whose mineral binding capabilities should be investigated further.
Effect of a Geriatric Nurse Education Program on the Knowledge, Attitudes, and Certification of Hospital Nurses
Authors: Donahue Moreen , Kazer Meredith Wallace , Smith Lisa , Fitzpatrick Joyce J.
Published: April 2011

Although nurses are the primary care providers for hospitalized and vulnerable older adults living in the community, they are generally not prepared in geriatric care. This study examined the effect of a 21-hour nursing education program on nurses’ knowledge and attitudes regarding care of older adults and the geriatric nursing certification of the participants. The program was offered to 92 nurses in three cohorts over a 1-year period. Participants completed pre- and posttest measures of geriatric knowledge and attitudes. Significant differences were found between pretest and posttest knowledge and attitudes. Program evaluation and success in achieving certification in gerontological nursing also indicated a positive effect of the program.
Innovations in Bereavement Education
Authors: Wright Patricia Moyle
Published: April 2011

Advanced practice nursing students provide care for clients and families in numerous settings where they will encounter end-of-life issues. Thus, graduate nursing education should include information on current trends in thanatology, such as the debate over the proposed complicated grief criteria and the paradigmatic shift toward evidence-based grief theory. In this article, an innovative approach to teaching bereavement content to graduate nursing students during a 3-hour class is presented. The assignments were developed specifically for adult learners with clinical experience. Students’ responses to the learning activities and recommendations for modifications of the teaching methods are presented.
Transforming Attitudes of Nursing Students: Evaluating a Service-Learning Experience
Authors: Loewenson Karen M. , Hunt Roberta J.
Published: April 2011

Homelessness is a compelling social and public health issue. Nurse educators are challenged to better prepare graduates to serve this growing segment of the population. Clinical experiences with those experiencing homelessness allow students a better understanding of this population and may foster more compassionate care. This pretest-posttest intervention study examined nursing students’ attitudes toward homelessness before and after participation in a service-learning clinical rotation with families experiencing homelessness. Twenty-three students enrolled in a public health nursing course at a small midwestern university participated in the research. The Attitudes Toward Homelessness Inventory was used to measure students’ attitudes at the beginning and end of the course. Data analysis using descriptive statistics revealed significant differences in both global and specific attitudes toward people experiencing homelessness. These results suggest the clinical experiences positively influenced students’ attitudes and support the value of integrating service-learning clinical opportunities with homeless individuals into nursing curricula.
Bridging the Gap Between Clinical Experience and Client Access: Community Engagement
Authors: Riedford Katherine B.
Published: April 2011

Service-learning involvement can be a useful adjunct to a traditional educational experience and can provide clinical exposure in mental health practice settings for undergraduate nursing students. Education and practice collaboratives in community settings benefit community partners through the service provided by students to the respective community organizations. Benefits to students are obvious through greater exposure to community agencies, avenues to meet academic clinical course objectives, and incentives for their critical and independent thinking. An overview of the process of engaging students in community engagement opportunities that provide clinical hours in an undergraduate mental health course is presented.
Wavefront-optimized Surface Ablation With the Allegretto Wave Eye-Q Excimer Laser Platform: 12-month Visual and Refractive Results
Authors: Gambato Catia , Catania Anton Giulio , Vujosevic Stela , Midena Edoardo
Published: April 2011

Purpose:

To evaluate the wavefront-optimized algorithm of the Allegretto Wave Eye-Q (Wavelight AG) 400-Hz excimer laser platform.

Methods:

Three hundred three eyes of 303 patients treated with advanced surface ablation were evaluated prospectively. Topical mitomycin C (MMC) was used when ablation was ≥80 μm. Efficacy, safety, and predictability at 12 months were quantified with subjective refraction, visual acuity (logMAR), and slit-lamp examination.

Results:

Mean postoperative uncorrected distance visual acuity (UDVA) was 20/20.5 (0.01±0.05 logMAR). Postoperative UDVA was equal or better than preoperative corrected distance visual acuity (CDVA) in 94.7% of eyes. Efficacy index was 1.05. Corrected distance visual acuity was maintained (93.7%) or improved (5.9%) in 99.6% of treated eyes. No patient lost ≥2 lines. Safety index was 1.05. Haze at 12 months was grade ≤0.5 in 98% of treated eyes and grade ≤1 in 100% of treated eyes. Mean postoperative manifest refraction spherical equivalent (MRSE) was −0.03±0.15 diopters (D). Postoperative MRSE was within ±0.50 D in 99% of eyes. Overcorrection was documented in 0.66% and undercorrection in 0.33% of eyes.

CONCLUSIONS:

The wavefront-optimized algorithm of the Allegretto Wave Eye-Q excimer laser platform showed good efficacy, safety, and predictability in advanced surface ablation, with or without MMC intraoperative use.
Early Hepatocellular Carcinoma: Transplantation versus Resection: The Case for Liver Resection
Authors: Merchant Nishant , David Calvin S. , Cunningham Steven C.
Published: April 2011

The optimal surgical treatment of hepatocellular carcinoma on well-compensated cirrhosis is controversial. Advocates of liver transplantation cite better long-term survival, lower risk of recurrence, and the ability of transplantation to treat both the HCC and the underlying liver cirrhosis. Transplantation, however, is not universally available to all appropriate-risk candidates because of a lack of sufficient organ donors and in addition suffers from the disadvantages of requiring a more complex pre- and postoperative management associated with risks of inaccessibility, noncompliance, and late complications. Resection, by contrast, is much more easily and widely available, avoids many of those risks, is by many accounts as effective at achieving similar long-term survival, and still allows for safe, subsequent liver transplantation in cases of recurrence. Here, arguments are made in favor of resection being easier, safer, simpler, and comparably effective in the treatment of HCC relative to transplantation, and therefore being the optimal initial treatment in cases of hepatocellular carcinoma on well-compensated cirrhosis.
Cord Blood-Derived Hematopoietic Stem/Progenitor Cells: Current Challenges in Engraftment, Infection, andEx VivoExpansion
Authors: Kita Katsuhiro , Lee Jong O. , Finnerty Celeste C. , Herndon David N.
Published: April 2011

Umbilical cord blood has served as an alternative to bone marrow for hematopoietic transplantation since the late 1980s. Numerous clinical studies have proven the efficacy of umbilical cord blood. Moreover, the possible immaturity of cells in umbilical cord blood gives more options to recipients with HLA mismatch and allows for the use of umbilical cord blood from unrelated donors. However, morbidity and mortality rates associated with hematopoietic malignancies still remain relatively high, even after cord blood transplantation. Infections and relapse are the major causes of death after cord blood transplantation in patients with hematopoietic diseases. Recently, new strategies have been introduced to improve these major problems. Establishing better protocols for simple isolation of primitive cells andex vivoexpansion will also be very important. In this short review, we discuss several recent promising findings related to the technical improvement of cord blood transplantation.
A Biocompatible Nanocomposite for Glucose Sensing
Authors: Rahimi Parvaneh , Ghourchian Hedayatollah , Rafiee-Pour Hossain-Ali , Norouzi Parviz , Ganjali Mohammad Reza
Published: April 2011

A nanocomposite containing amine functionalized multiwalled carbon nanotubes and a room temperature ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate) was prepared and applied for glucose oxidase (GOx) immobilization on glassy carbon electrode. The proposed nanocomposite provided a favorable microenvironment to preserve the bioactivity of GOx. It could also effectively facilitate the enzyme direct electron transfer to the electrode. This brought about a remarkable improvement in the sensitivity of the glucose biosensor. Under the optimum experimental conditions, the formal potential of GOx was about −467.5 mV. Moreover, the sensitivity and response time of the biosensor toward glucose were 1277 μA mM-1 cm-2and 6 s, respectively. The biosensor provided a linear dynamic response between 0.1 and 43 μM with a very low detection limit of 63 nM. Also, the values for apparent Michaelis-Menten constant and maximum current were obtained as 18 μM and 2.7 μA, respectively.
Functionally Relevant Residues of Cdr1p: A Multidrug ABC Transporter of Human Pathogenic Candida albicans
Authors: Prasad Rajendra , Sharma Monika , Rawal Manpreet Kaur
Published: April 2011

Reduced intracellular accumulation of drugs (due to rapid efflux) mediated by the efflux pump proteins belonging to ABC (ATP Binding Cassette) and MFS (Major Facilitators) superfamily is one of the most common strategies adopted by multidrug resistance (MDR) pathogenic yeasts. To combat MDR, it is essential to understand the structure and function of these transporters so that inhibitors/modulators to these can be developed. The sequence alignments of the ABC transporters reveal selective divergence within much conserved domains of Nucleotide-Binding Domains (NBDs) which is unique to all fungal transporters. Recently, the role of conserved but divergent residues of Candida Drug Resistance 1 (CDR1), an ABC drug transporter of human pathogenic Candida albicans, has been examined with regard to ATP binding and hydrolysis. In this paper, we focus on some of the recent advances on the relevance of divergent and conserved amino acids of CaCdr1p and also discuss as to how drug interacts with Trans Membrane Domains (TMDs) residues for its extrusion from MDR cells.
Do Somatic Mitochondrial DNA Mutations Contribute to Parkinson's Disease?
Authors: Clark Joanne , Dai Ying , Simon David K.
Published: April 2011

A great deal of evidence supports a role for mitochondrial dysfunction in the pathogenesis of Parkinson's disease (PD), although the origin of the mitochondrial dysfunction in PD remains unclear. Expression of mitochondrial DNA (mtDNA) from PD patients in “cybrid” cell lines recapitulates the mitochondrial defect, implicating a role for mtDNA mutations, but the specific mutations responsible for the mitochondrial dysfunction in PD have been difficult to identify. Somatic mtDNA point mutations and deletions accumulate with age and reach high levels in substantia nigra (SN) neurons. Mutations in mitochondrial DNA polymeraseγ(POLG) that lead to the accumulation of mtDNA mutations are associated with a premature aging phenotype in “mutator” mice, although overt parkinsonism has not been reported in these mice, and with parkinsonism in humans. Together these data support, but do not yet prove, the hypothesis that the accumulation of somatic mtDNA mutations in SN neurons contribute to the pathogenesis of PD.
Endothelial Progenitor Cells in Acute Ischemic Kidney Injury: Strategies for Increasing the Cells' Renoprotective Competence
Authors: Patschan D. , Patschan S. , Müller G. A.
Published: April 2011

Acute ischemic kidney injury is the most frequent cause of acute renal failure in daily clinical practice. It has become increasingly recognized that microvascular endothelial cell dysfunction (ED) in peritubular capillaries inhibits the process of postischemic renal reperfusion. ED can serve as therapeutic target in the management of acute ischemic kidney injury. Postischemic reflow can be restored by systemic administration of either mature endothelial cells or of endothelial progenitor cells. Endothelial progenitor cells EPCs can be cultured from the peripheral circulation of humans and different animals. The cells act vasoprotectively by direct and indirect mechanisms. The protective effects of EPCs in acute ischemic kidney injury can be stimulated by preincubating the cells with different agonistic mediators. This paper summarizes the currently available data on strategies to improve the renoprotective activity of EPCs in acute ischemic kidney injury.
Three cases of bone metastases in patients with gastrointestinal stromal tumors
Authors: Di Scioscio Valerio , Greco Laura , Pallotti Maria Caterina , Pantaleo Maria Abbondanza , Maleddu Alessandra , Nannini Margherita , Bazzocchi Alberto , Di Battista Monica , Mandrioli Anna , Lolli Cristian , Saponara Maristella , Giorgio Garzillo , Biasco Guido , Zompatori Maurizio
Published: April 2011

Gastrointestinal stromal tumors (GISTs) are rare, but represent the most common mesenchymal neoplasms of the gastrointestinal tract. Tumor resection is the treatment of choice for localized disease. Tyrosine kinase inhibitors (imatinib, sunitinib) are the standard therapy for metastatic or unresectable GISTs. GISTs usually metastasize to the liver and peritoneum. Bone metastases are uncommon. We describe three cases of bone metastases in patients with advanced GISTs: two women (82 and 54 years of age), and one man (62 years of age). Bones metastases involved the spine, pelvis and ribs in one patient, multiple vertebral bodies and pelvis in one, and the spine and iliac wings in the third case. The lesions presented a lytic pattern in all cases. Two patients presented with multiple bone metastases at the time of initial diagnosis and one patient after seven years during the follow-up period. This report describes the diagnosis and treatment of the lesions and may help clinicians to manage bones metastases in GIST patients.
Uncorrected Tetralogy of Fallot in a 25-Year Old Nigerian African
Authors: Ojji Dike B. , Babalola Akinola O. , Falase Ayodele O.
Published: April 2011

Tetralogy of Fallot is the most common form of cyanotic congenital heart disease. Survival after the age of 12 years without corrective surgery is rare. We present the case of a 25 year-old man with uncorrected tetralogy of Fallot. Possible reasons for the longetivity in this patient are left ventricular hypertrophy and systemic to pulmonary shunting through internal mammary arteries.
A Jackknife and Voting Classifier Approach to Feature Selection and Classification
Authors: Taylor Sandra L. , Kim Kyoungmi
Published: April 2011

With technological advances now allowing measurement of thousands of genes, proteins and metabolites, researchers are using this information to develop diagnostic and prognostic tests and discern the biological pathways underlying diseases. Often, an investigator's objective is to develop a classification rule to predict group membership of unknown samples based on a small set of features and that could ultimately be used in a clinical setting. While common classification methods such as random forest and support vector machines are effective at separating groups, they do not directly translate into a clinically-applicable classification rule based on a small number of features. We present a simple feature selection and classification method for biomarker detection that is intuitively understandable and can be directly extended for application to a clinical setting. We first use a jackknife procedure to identify important features and then, for classification, we use voting classifiers which are simple and easy to implement. We compared our method to random forest and support vector machines using three benchmark cancer ‘omics datasets with different characteristics. We found our jackknife procedure and voting classifier to perform comparably to these two methods in terms of accuracy. Further, the jackknife procedure yielded stable feature sets. Voting classifiers in combination with a robust feature selection method such as our jackknife procedure offer an effective, simple and intuitive approach to feature selection and classification with a clear extension to clinical applications.
Blockade of Caspase-2 Activity Inhibits Ischemia/Reperfusion-Induced Mitochondrial Reactive Oxygen Burst and Cell Death in Cardiomyocytes
Authors: Shao Zuo-Hui , Wojcik Kimberly R. , Qin Yimin , Li Chang-Qing , Hoek Terry L. Vanden , Hamann Kimm J.
Published: April 2011

We previously showed that initiator caspases-2 and −8 are prominently activated in ischemia/reperfusion (I/R)-induced injury in cardiomyocytes, but while blockade of caspase-2 activity enhanced cell survival, blockade of caspase-8 activity did not protect cardiomyocytes. Because apoptotic death in these cells is characterized by a burst of reactive oxygen species (ROS) at reperfusion and their survival by inhibition of this burst, we examined the effects of blocking caspase-2 and caspase-8 activities on ROS production. Caspase-2 inhibition blocked the reperfusion-induced ROS burst, while inhibition of caspase-8 did not. We also examined effects of caspase inhibition on mitochondrial membrane potential (ΔΨm) and mitochondrial function and found that blocking caspase-2, but not caspase-8, allowed recovery of ΔΨm and mitochondrial functionality. Furthermore, knockdown of caspase-2 by small-interfering (si)RNA confirmed caspase-2 participation in cytochrome c release, which correlates with loss of ΔΨm and cell death in these cardiomyocytes.
Irreducible Representations of Inner Quasidiagonal C*-Algebras
Authors: Blackadar Bruce , Kirchberg Eberhard
Published: April 2011

It is shown that a separable C*-algebra is inner quasidiagonal if and only if it has a separating family of quasidiagonal irreducible representations. As a consequence, a separable C*-algebra is a strong NF algebra if and only if it is nuclear and has a separating family of quasidiagonal irreducible representations. We also obtain some permanence properties of the class of inner quasidiagonal C*-algebras.
The Group Aut (μ) is Roelcke Precompact
Authors: Glasner Eli
Published: April 2011

Following a similar result of Uspenskij on the unitary group of a separable Hilbert space, we show that, with respect to the lower (or Roelcke) uniform structure, the Polish group G = Aut(μ) of automorphisms of an atomless standard Borel probability space (X, μ) is precompact. We identify the corresponding compactification as the space of Markov operators on L2(μ) and deduce that the algebra of right and left uniformly continuous functions, the algebra of weakly almost periodic functions, and the algebra of Hilbert functions on G, i.e., functions on G arising from unitary representations, all coincide. Again following Uspenskij, we also conclude that G is totally minimal.
Magnitude and seasonality of wetland methane emissions from the Hudson Bay Lowlands (Canada)
Authors: Pickett-Heaps C. A. , Jacob D. J. , Wecht K. J. , Kort E. A. , Wofsy S. C. , Diskin G. S. , Worthy D. E. J. , Kaplan J. O. , Bey I. , Drevet J.
Published: April 2011

Abstract. The Hudson Bay Lowlands (HBL) is the second largest boreal wetland ecosystem in the world and an important natural source of global atmospheric methane. We quantify the HBL methane emissions by using the GEOS-Chem chemical transport model to simulate aircraft measurements over the HBL from the ARCTAS and pre-HIPPO campaigns in May–July 2008, together with continuous 2004–2008 surface observations at Fraserdale (southern edge of HBL) and Alert (Arctic background). The difference in methane concentrations between Fraserdale and Alert is shown to be a good indicator of HBL emissions, and implies a sharp seasonal onset of emissions in late May (consistent with the aircraft data), a peak in July–August, and a seasonal shut-off in September. The model, in which seasonal variation of emission is mainly driven by surface temperature, reproduces well the observations in summer but its seasonal shoulders are too broad. We suggest that this reflects the suppression of emissions by snow cover and greatly improve the model simulation by accounting for this effect. Our resulting best estimate for HBL methane emissions is 2.3 Tg a−1, several-fold higher than previous estimates (Roulet et al., 1994; Worthy et al., 2000).
The role of tropical deep convective clouds on temperature, water vapor, and dehydration in the tropical tropopause layer (TTL)
Authors: Chae J. H. , Wu D. L. , Read W. G. , Sherwood S. C.
Published: April 2011

Abstract. Temperature and water vapor variations due to clouds in the tropical tropopause layer (TTL) are investigated using co-located MLS, CALIPSO, and CloudSat data. Convective cooling occurs only up to the cloud tops, with warming above these heights in the TTL. Water vapor and ozone anomalies above the cloud tops are consistent with the warming being due to downward motion. Thicker clouds are associated with larger anomalies. Environmental water vapor below cloud tops can be either higher or lower than when clouds are absent, depending on the cloud top height. The critical factor determining the sign of this change appears to be the relative humidity. In general cloud-forming processes hydrate the environment below 16 km, where the air after mixing between cloud and the environmental air does not reach saturation, but clouds dehydrate above 16 km, as the larger temperature drop and the high initial relative humidity cause supersaturation to occur. Negative water vapor anomalies above cloud tops compared to clear skies suggest another dehydration mechanism operating above the detected cloud layers.
Chemical ageing and transformation of diffusivity in semi-solid multi-component organic aerosol particles
Authors: Pfrang C. , Shiraiwa M. , Pöschl U.
Published: April 2011

Abstract. Recent experimental evidence underlines the importance of reduced diffusivity in amorphous semi-solid or glassy atmospheric aerosols. This paper investigates the impact of diffusivity on the ageing of multi-component reactive organic particles representative of atmospheric cooking aerosols. We apply and extend the recently developed KM-SUB model in a study of a 12-component mixture containing oleic and palmitoleic acids. We demonstrate that changes in the diffusivity may explain the evolution of chemical loss rates in ageing semi-solid particles, and we resolve surface and bulk processes under transient reaction conditions considering diffusivities altered by oligomerisation. This new model treatment allows prediction of the ageing of mixed organic multi-component aerosols over atmospherically relevant time scales and conditions. We illustrate the impact of changing diffusivity on the chemical half-life of reactive components in semi-solid particles, and we demonstrate how solidification and crust formation at the particle surface can affect the chemical transformation of organic aerosols.
Observations of an auroral streamer in a double oval configuration
Authors: Amm O. , Nakamura R. , Takada T. , Kauristie K. , Frey H. U. , Owen C. J. , Aikio A. , Kuula R.
Published: April 2011

Abstract. During the late evening and night of 14 September 2004, the nightside auroral oval shows a distinct double oval configuration for several hours after a substorm onset at ~18:45 UT. This structure is observed both by the IMAGE satellite optical instruments focusing on the Southern Hemisphere, and by the MIRACLE ground-based instrument network in Scandinavia. At ~21:17 UT during the recovery phase of the substorm, an auroral streamer is detected by these instruments and the EISCAT radar, while simultaneously the Cluster satellites observe a bursty bulk flow in the conjugate portion of the plasma sheet in the magnetotail. Our combined data analysis reveals significant differences between the ionospheric equivalent current signature of this streamer within a double oval configuration, as compared to previously studied streamer events without such a configuration. We attribute these differences to the presence of an additional poleward polarization electric field between the poleward and the equatorward portions of the double oval, and show with a simple model that such an assumption can conceptually explain the observations. Further, we estimate the total current transferred in meridional direction by this recovery phase streamer to ~80 kA, significantly less than for previously analysed expansion phase streamer events. Both results indicate that the development of auroral streamers is dependent on the ambient background conditions in the magnetosphere-ionosphere system. The auroral streamer event studied was simultaneously observed in the conjugate Northern and Southern Hemisphere ionosphere.
Process-based distributed modeling approach for analysis of sediment dynamics in a river basin
Authors: Kabir M. A. , Dutta D. , Hironaka S.
Published: April 2011

Abstract. Modeling of sediment dynamics for developing best management practices of reducing soil erosion and of sediment control has become essential for sustainable management of watersheds. Precise estimation of sediment dynamics is very important since soils are a major component of enormous environmental processes and sediment transport controls lake and river pollution extensively. Different hydrological processes govern sediment dynamics in a river basin, which are highly variable in spatial and temporal scales. This paper presents a process-based distributed modeling approach for analysis of sediment dynamics at river basin scale by integrating sediment processes (soil erosion, sediment transport and deposition) with an existing process-based distributed hydrological model. In this modeling approach, the watershed is divided into an array of homogeneous grids to capture the catchment spatial heterogeneity. Hillslope and river sediment dynamic processes have been modeled separately and linked to each other consistently. Water flow and sediment transport at different land grids and river nodes are modeled using one dimensional kinematic wave approximation of Saint-Venant equations. The mechanics of sediment dynamics are integrated into the model using representative physical equations after a comprehensive review. The model has been tested on river basins in two different hydro climatic areas, the Abukuma River Basin, Japan and Latrobe River Basin, Australia. Sediment transport and deposition are modeled using Govers transport capacity equation. All spatial datasets, such as, Digital Elevation Model (DEM), land use and soil classification data, etc., have been prepared using raster "Geographic Information System (GIS)" tools. The results of relevant statistical checks (Nash-Sutcliffe efficiency and R–squared value) indicate that the model simulates basin hydrology and its associated sediment dynamics reasonably well. This paper presents the model including descriptions of the various components and the results of its application on two case study areas.
Development of Black Sea nowcasting and forecasting system
Authors: Korotaev G. K. , Oguz T. , Dorofeyev V. L. , Demyshev S. G. , Kubryakov A. I. , Ratner Y. B.
Published: April 2011

Abstract. The paper presents the development of the Black Sea community nowcasting and forecasting system under the Black Sea GOOS initiative and the EU framework projects ARENA, ASCABOS and ECOOP. One of the objectives of the Black Sea Global Ocean Observing System project is a promotion of the nowcasting and forecasting system of the Black Sea, in order to implement the operational oceanography in the Black Sea region. The first phase in the realization of this goal was the development of the pilot nowcasting and forecasting system of the Black Sea circulation in the framework of project ARENA funded by the EU. The ARENA project included the implementation of advanced modeling and data assimilation tools for near real time prediction. Further progress in development of the Black Sea nowcasting and forecasting system was made in the frame of ASCABOS project, which was targeted at strengthening the communication system, ensuring flexible and operative infrastructure for data and information exchange between the Black Sea partners and end-users. The improvement of the system was made in the framework of the ECOOP project. As a result it was transformed into a real-time mode operational nowcasting and forecasting system. The paper provides the general description of the main parts of the system: circulation and ecosystem models, data assimilation approaches, the system architecture as well as their qualitative and quantitative calibrations.
Living Donor Liver Transplantation for Caroli's Disease: A Report of Two Cases
Authors: Steinbrück Klaus , Enne Marcelo , Fernandes Reinaldo , Martinho Jose M. , Pacheco-Moreira Lúcio F.
Published: April 2011

Caroli's disease (CD) is a rare autosomal recessive disorder characterized by intrahepatic cystic dilatation of the bile ducts. Patients with bilobar or progressive disease may require orthotopic liver transplantation (OLT). In the MELD era, living donor liver transplantation (LDLT) raised as the ultimate treatment option for these patients, once their MELD score is usually low. Herein, we describe 2 cases of patients (a 2-year-old girl and a 19-year-old teenager) that successfully underwent LDLT as a treatment for diffuse CD. The good postoperative courses of the two cases indicate that LDLT is a feasible option in the treatment of this disorder, even in complicated or early age patients.
Affine Projection Algorithm Using Regressive Estimated Error
Authors: Zhang Shu , Zhi Yongfeng
Published: April 2011

An affine projection algorithm using regressive estimated error (APA-REE) is presented in this paper. By redefining the iterated error of the affine projection algorithm (APA), a new algorithm is obtained, and it improves the adaptive filtering convergence rate. We analyze the iterated error signal and the stability for the APA-REE algorithm. The steady-state weights of the APA-REE algorithm are proved to be unbiased and consist. The simulation results show that the proposed algorithm has a fast convergence rate compared with the APA algorithm.
Emergency Pancreaticoduodenectomy in Duodenal Paraganglioma: Case Report
Authors: Parray Fazl Q. , Lone Iqbal M. , Chowdri Nisar A. , Wani Imtiaz , Wani Mehmood A. , Gulzar G. M. , Thakur Natasha
Published: April 2011

Duodenal gangliocytic paraganglioma (DGP) is a rare tumor that characteristically occurs in the second part of duodenum. These appear as submucosal masses that protrude into the lumen of a duodenum. Gastrointestinal bleeding is the commonest manifestation of DGP. Metastatic spread to regional lymph nodes occurs rarely. Surgical resection is the treatment of choice for DGP. A case of a DGP is reported in young female who presented with a recurrent upper gastrointestinal bleeding. Upper gastrointestinal endoscopy (UGIE) documented a mass in the ampullary region with ulceration in its middle which was bleeding. Recurrent gastrointestinal bleeding necessitated an emergency pancreaticoduodenectomy. Histopathology of specimen documented gangliocytic paraganglioma.
Photodynamic Therapy for Basal Cell Carcinoma in Recessive Dystrophic Epidermolysis Bullosa
Authors: Lee Myn Wee , Varigos George , Foley Peter , Ross Gayle
Published: April 2011

A 22-year-old male with recessive dystrophic epidermolysis bullosa with a large superficial and nodular basal cell carcinoma on his right forehead was treated with photodynamic therapy. The treatment was well tolerated, and the site healed well. Patients with epidermolysis bullosa are at increased risk of developing skin cancers, particularly squamous cell carcinomas. However, basal cell carcinomas are rare in recessive dystrophic epidermolysis bullosa. As patients with epidermolysis bullosa have recurrent blistering and poor wound healing, surgery may not be the optimal choice in treating skin cancers. We present this case to highlight that photodynamic therapy may be a helpful and safe technique in the treatment of superficial skin cancers in patients with epidermolysis bullosa, as an alternative to more radical methods.
Downstaging of TURBT-Based Muscle-Invasive Bladder Cancer by Radical Cystectomy Predicts Better Survival
Authors: van Dijk P. R. , Ploeg M. , Aben K. K. H. , Weijerman P. C. , Karthaus H. F. M. , van Berkel J. Th. H. , Viddeleer A. C. , Geboers A. , van Boven E. , Witjes J. A. , Kiemeney L. A. L. M.
Published: April 2011

Differences between clinical (cT) and pathological tumor (pT) stage occur often after radical cystectomy (RC) for muscle-invasive bladder cancer. In order to evaluate the impact of downstaging on recurrence and survival, we selected patients from a large, contemporary, population-based series of 1,409 patients with MIBC. We included all patients who underwent RC (N=643) and excluded patients who received (neo)adjuvant therapy, those with known metastasis at time of diagnosis, and those with nonurothelial cell tumors. Disease outcomes were defined as recurrence-free survival (RFS) and relative survival (RS), as a good approximation of bladder cancer-specific survival. After applying the exclusion criteria, 375 patients were eligible for analysis. Tumor downstaging was found to be common after RC; in 99 patients (26.4%), tumor downstaging to non-muscle-invasive stages at RC occurred. Hydronephrosis at baseline and positive lymph nodes at RC occurred significantly less often in these patients. In 62 patients, no tumor was left in the cystectomy specimen. pT stage was pT1 in 20 patients and pTis in 17 patients. Patients with tumor downstaging have about a 30% higher RFS and RS compared to those without. Consequently, tumor downstaging is a favorable marker for prognosis after RC.
Study of Carbon Nanotube-Supported Platinum Nanocatalyst Fabricated with Sodium Formate Reducing Agent in Ethylene Glycol Suspension
Authors: Mason C. W. , Kannan A. M.
Published: April 2011

A simple method to prepare a durable, low platinum-loading catalyst layer for the cathode in a proton exchange membrane fuel cell is tested and described. Multiwalled carbon nanotubes (MWCNTs) are functionalized with citric acid and then suspended in ethylene glycol. Here, platinum nanoparticles (~4 nm) are loaded onto the surface of the MWCNTs after hexachloroplatinic acid is reduced by aqueous sodium formate. A peak performance of 813 mW⋅cm−2 was achieved with a total membrane electrode assembly (MEA) platinum catalyst loading of 0.2 mg⋅cm−2 (0.1 mg⋅cm−2 anode/0.1 mg⋅cm−2 cathode), in H2/O2 (ambient pressure), at 80°C, with a Nafion 212 membrane. Peak power density only decreased by 23% after 1500 potentials cycles (ranged from 0.1 to 1.2 V, and vice versa, with a 50 mV/s scan rate, flowing H2/N2 at 80°C). Transmission electron microscopy (TEM) images show the morphology and distribution of the platinum nanoparticles loaded onto the surface of the MWCNTs.
Potential Effects of Host Height and Phenology on Adult Susceptibility to Foliar Attack in Tropical Dry Forest Grass
Authors: Santos Bráulio A. , Quesada Mauricio , Rosas Fernando , Benítez-Malvido Julieta
Published: April 2011

Identifying the sources of variation in plant susceptibility to herbivore and pathogen attack is critical to understand ecological processes determining species abundance and diversity in tropical forests. We assessed the potential effect of tiller height and phenology on standing levels of herbivore and pathogen damage on adults of the woody perennial grass Lasiacis ruscifolia in the tropical dry forest of Chamela, Mexico. Analyses revealed that adult susceptibility to pathogens was greater in small and fruiting tillers than in taller and leaf flushing tillers. Adult susceptibility to herbivores, on the other hand, varied greatly among plants and had no relationship with tiller height and phenology. Our findings suggest that adults highly susceptible to pathogen attack could augment the negative density and distance dependence effects predicted by the Janzen-Connell hypothesis, with potential consequences for the local distribution of the studied species in the forest.
A Novel Dynamic Bandwidth Allocation Mechanism for Star-Ring-Based EPON
Authors: Hwang I-Shyan , Lee Jhong-Yue , Shyu Zen-Der
Published: April 2011

Ethernet Passive Optical Network (EPON) is proposed as a simple, cost-effective and scalable solution for bandwidth bottlenecks in access networks which can enhance the system performance because it transmits the aggregated high-speed traffic from hundreds of subscribers. Dynamic Bandwidth Allocation (DBA) mechanism has not yet been seriously considered for use in star-ring EPON architecture. In this paper, a distributed QoS-based dynamic bandwidth allocation (DQ-DBA) scheduling mechanism for the star-ring-based EPON architecture including optical line terminal (OLT), Sub-OLT and ONUs has been proposed to improve the system performance of traditional tree-based EPON architecture. In DQ-DBA, the highest-priority traffic of each ONU is directed to the OLT by the tree structure; moreover, the lower-priority traffic on each ONU is transmitted to the Sub-OLT by ring architecture. This approach can effectively resolve the idle period problem and reduce the overloading of OLT in conventional DBA mechanisms. Exhaustive simulation experiments are performed to compare the system performance between the tree and the star-ring architectures and validate the effectiveness of the proposed mechanism. Simulation results show that the proposed DQ-DBA mechanism in star-ring architecture can reduce packet delay and jitter for the high-priority traffic, thus ensuring the quality of service (QoS) regardless of subscriber numbers.
Copper Perchlorate Hexahydrate: An Efficient Catalyst for the Green Synthesis of Polyhydroquinolines under Ultrasonication
Authors: Puri Saurabh , Kaur Balbir , Parmar Anupama , Kumar Harish
Published: April 2011

Copper perchlorate hexahydrate as an efficient catalyst was used for the synthesis of polyhydroquinolines by four-component condensation reaction of aldehyde, ethyl acetoacetate, dimedone, and ammonium acetate in excellent yields and short reaction times at room temperature under ultrasound irradiation. This novel synthetic method is especially favoured because it provides a synergy between copper perchlorate hexahydrate and ultrasound irradiation which offers the advantages of high yields, short reaction times, simplicity, and easy workup compared to the conventional methods reported in the literature.