bluuebunny/crossref_metadata_2025 huggingface dataset:
Evolution of the Hepatitis E Virus Polyproline Region: Order from Disorder
Authors: Purdy Michael A.
Published: July 2012

The hepatitis E virus (HEV) polyproline region (PPR) is an intrinsically unstructured region (IDR). This relaxed structure allows IDRs, which are implicated in the regulation of transcription and translation, to bind multiple ligands. Originally the nucleotide variability seen in the HEV PPR was assumed to be due to high rates of insertion and deletion. This study shows that the mutation rate is about the same in the PPR as in the rest of the nonstructural polyprotein. The difference between the PPR and the rest of the polyprotein is due to the higher tolerance of the PPR for substitutions at the first and second codon positions. With this higher promiscuity there is a shift in nucleotide occupation of these codons leading to translation of more cytosine residues: a shift that leads to more proline, alanine, serine, and threonine being encoded rather than histidine, phenylalanine, tryptophan, and tyrosine. This pattern of amino acid usage is typical of proline-rich IDRs. Increased usage of cytosine also leads to >22% of all amino acids in the PPR being prolines. Alignments of PPR sequences from HEV strains representing all genotypes indicate that all zoonotic isolates share an ancestor, and the carboxyl half of the PPR is more tolerant of mutations than the amino half. The evolution of HEV PPR, in contrast with that of the rest of the nonstructural polyprotein, is molded by pressures that lead toward increased proline usage with a corresponding decrease in the usage of aromatic amino acids, favoring formation of IDR structures.
Hand-biting and hand-waving paroxysms in epilepsy
Authors: Selikhova Marianna , Scott Catherine , Silva Mark , Rugg-Gunn Furgus
Published: July 2012

A 20-year-old ambidextrous female student with a 15-year history of refractory seizures was admitted to the epilepsy department for a second opinion on her diagnosis and treatment. She developed frequent motor paroxysms at the age of 4–5 years, which appeared resistant to antiepileptic therapy and which have continued to the present day. Over the last 8 years she also had five generalised tonic-clonic seizures. There is a family history of epilepsy on the maternal side. The first type of episode is characterised by left-hand flickering, associated with head turning and loss of awareness. During the second type of attack the patient demonstrates vigorous hand biting which starts without warning. The patient appears disorientated subsequently. EEG telemetry was performed and confirmed the diagnosis of both epilepsy and non-epileptic attacks. Literature reports of the relevant cases are discussed.
Successful salvage using combined radiation and ABMT for patients with recurrent CNS NGGCT following failed initial transplant
Authors: Malone Kyle , Croke Jennifer , Malone Colin , Malone Shawn
Published: July 2012

Intracranial germ cell tumours (GCTs) are a rare and diverse group of tumours. Histology determines the type of treatment, natural history and prognosis. Germinoma GCTs account for the majority and are very radiosensitive. Conversely, non-germinoma GCTs (NGGCTs) are heterogeneous, relatively radioresistant and have a high risk of relapse despite multimodality therapy. Treatment of recurrence in these patients remains a therapeutic challenge. In this report we review the current literature for treatment of recurrent NGGCTs and present a case of recurrent NGGCT who relapsed despite autologous stem cell transplant (ASCT). The patient was successfully cured using multimodality therapy, consisting of repeat ASCT, intensity modulated radiation therapy and stereotactic radiosurgery.
IVIG treatment for VZV-related acute inflammatory polyneuropathy in a child: Figure 1
Authors: Buonsenso Danilo , Focarelli Benedetta , Valentini Piero , Onesimo Roberta
Published: July 2012

Acute inflammatory polyneuropathy is an inflammatory demyelinating disease triggered by an autoimmune mechanism. It follows an infection or an immunisation after a free interval of 2–30 days. We report a case of a 14-year-old boy who develops an acute rapidly progressive paraplegia, urine incontinence and positive Lasegue a week after a characteristic chickenpox rash. Spinal MRI showed diffuse thickening and leptomeningeal enhancement of cauda equina nerve roots. Intravenous immunoglobulins were given and yielded a dramatic clinical and radiological improvement. The patient was discharged without any clinical problems 1 month after the onset of symptoms. We performed a review of the literature, discussing the different forms of varicella-zoster virus-related central and peripheral nervous system complications and management strategies for acute postinfectious encephalomyelitis/radiculitis.
Bilateral facial palsy as a manifestation of Japanese encephalitis: Figure 1
Authors: Verma Rajesh , Praharaj Heramba Narayan
Published: July 2012

Japanese encephalitis is a cause of substantial morbidity and mortality, prevalent mainly in South East nations. It is caused by group B arbovirus and transmitted with bite of infected culex mosquitoes. The clinical features described are: headache, vomiting, altered sensorium, convulsions and both hypokinetic and hyperkinetic movement disorders. In this submission, we described a 68-year-old man suffering from Japanese encephalitis, who presented with bilateral facial palsy with encephalitic features. The bilateral facial palsy has not been reported previously in association with Japanese encephalitis.
Oropharyngeal teratoma, a rare cause of airway obstruction in neonates
Authors: Bahgat Mohammed , Bahgat Yassin , Bahgat Ahmed
Published: July 2012

Oropharyngeal teratomas are extremely rare congenital tumours, and because of their location in the upper airway they represent one of the most unusual causes of airway obstruction during the neonatal period. We report a 2-month-old girl who presented with repeated vomiting, failure to thrive and recurrent bouts of stridor and cyanosis since birth. On examination there was a mass originating from the oropharynx. The mass was excised under general anaesthesia by CO2laser. Histopathological examination revealed a teratoma of the oropharynx. We discuss the clinical presentation, diagnosis and treatment of this case as well as a review of the literature.
Bloody nipple discharge in infancy—report of two cases: Figure 1
Authors: Nascimento Marta , Portela Alexandrina , Espada Filipa , Fonseca Marcelo
Published: July 2012

Bloody nipple discharge (BND) in infancy is an exceptionally rare finding. We report the cases of two children who are 9 and 29 months old. The first case presented with 1 month of bilateral intermittent blood-stained nipple discharge with no other symptoms. The second case presented with 15 days of intermittent right BND and a small palpable mass, without obvious signs of inflammation. The coagulation and hormonal tests were within the age-appropriate reference ranges. Ultrasound examination was normal. Cytological evaluation of nipple discharge showed no malignant cells. Both patients had spontaneous symptoms resolution. BND in paediatric age is usually benign and self-limited and often related to mammary duct ectasia. Unnecessary invasive procedures or treatments should be avoided.
Timing of growth reductions in black spruce stem and branches during the 1970s spruce budworm outbreak1This article is one of a selection of papers from the 7th International Conference on Disturbance Dynamics in Boreal Forests.
Authors: Krause Cornelia , Luszczynski Boris , Morin Hubert , Rossi Sergio , Plourde Pierre-Y.
Published: July 2012

Spruce budworm ( Choristoneura fumiferana (Clemens)) defoliation is known to regularly produce radial growth decrease in black spruce ( Picea mariana (Mill.) Britton, Sterns & Poggenb.) in the boreal forest of Quebec. Some studies have already shown that the first year of defoliation does not induce growth losses in the stem but could occur in other tree parts. We therefore examined the timing and duration of the growth reduction caused by the last outbreak in black spruce by also considering the branches. More than 79% of branches and 65% of stems exhibited a >40% growth decrease.The reduction was first registered in the upper part of the stem before being detected lower in the stem in 87% of the trees. Probabilities of growth reduction in the upper part of the stem were highest in 1976 and 1977. In the lower stem, the probabilities were highest in 1978. An interesting finding was that in 69% of the studied stands, the probability of growth reduction started earlier (1–2 years) in the branches than in the stem at 1.3 m. Branch analysis should be considered whenever questions arise in regard to the evolution of spruce budworm defoliation as well as the timing of observed growth reduction in black spruce.
Increasing nitrogen availability and soil temperature: effects on xylem phenology and anatomy of mature black spruce1This article is one of a selection of papers from the 7th International Conference on Disturbance Dynamics in Boreal Forests.
Authors: Lupi Carlo , Morin Hubert , Deslauriers Annie , Rossi Sergio , Houle Daniel
Published: July 2012

Since plant growth in the boreal forest is often considered to be limited by low temperatures and low N availability and these variables are projected to increase due to climate warming and increased anthropogenic activities, it is important to understand whether and to what extent these disturbances may affect the growth of boreal trees. In this study, the hypotheses that wood phenology and anatomy were affected by increased soil temperatures and N depositions have been tested in two mature black spruce ( Picea mariana (Mill.) BSP) stands at different altitudes in Quebec, Canada. For 3 years, soil temperature was increased by 4 °C during the first part of the growing season and precipitations containing three times the current N concentration were added in the field by frequent canopy applications. Soil warming resulted in earlier onsets of xylogenesis and interacted with N addition producing longer durations of xylogenesis for the treated trees. The effect of warming was especially marked in the phenology of roots, while wood production, in terms of number of tracheids, was not affected by the treatment. Xylem anatomy and soil and needle chemistry showed no effect of the treatments, except for an increase of cell wall thickness in earlywood of treated trees. This short-term experiment with black spruce suggested that previous fertilization studies that used large and unrealistic rates of N addition may have overestimated the impact of N depositions on boreal forest productivity.
The influence of wildfire boundary delineation on our understanding of burning patterns in the Alberta foothills1This article is one of a selection of papers from the 7th International Conference on Disturbance Dynamics in Boreal Forests.
Authors: Andison David W.
Published: July 2012

Under the auspices of ecosystem-based management, historical disturbance patterns are promoted as a means of providing benchmarks for ecosystem sustainability. The associated research in support of this strategy in the boreal forest has substantially increased our understanding of frequencies, sizes, shapes, and severities of wildfires. However, despite the fact that different spatial definitions of wildfires exist in both research and practice, we have not considered the significance or impact of those differences on observed patterns. This study addresses this gap by conducting a sensitivity analysis on the influence of 11 spatial definitions of a wildfire on six pattern metrics for 24 wildfires in the Foothills Natural Region of Alberta. The results suggest that all pattern metrics were sensitive to changes to wildfire delineation, but in particular the total amount of remnants, wildfire shape, and the relationship between pre-burn fuel types and the probability of burning. The results also suggest that simple mortality maps do not necessarily identify multiple disturbed patches within wildfires, an attribute undocumented by previous research. These pattern differences potentially correspond to some fundamental differences in perception of how and why wildfires burn and our understanding of the associated processes and biological responses.
Recent impact of fire on high-altitude balsam fir forests in south-central Quebec1This article is one of a selection of papers from the 7th International Conference on Disturbance Dynamics in Boreal Forests.
Authors: Couillard Pierre-Luc , Payette Serge , Grondin Pierre
Published: July 2012

The dynamics of high-altitude balsam fir ( Abies balsamea (L.) Mill.) forests is mainly driven by insect outbreaks and windthrows. However, very little work has been done on the role of fire on the development and maintenance of this ecosystem. In this study, we document the role of fire in the high-altitude balsam fir forests of the Réserve Faunique des Laurentides (RFL), southern Quebec. Sixteen sites were sampled among six different forest types described according to plant composition and fire evidence. At each site, the diameter structure was recorded and stand age was calculated based on tree-ring dating of individual trees and radiocarbon-dated surficial charcoal samples. Fire played a major role in the recent dynamics of high-altitude fir forests in the RFL. Over the last 250 years, nearly 50% of the study area burned during two fire conflagrations, i.e., around 1815 and in 1878. The fires triggered gradual changes in plant composition and forest structure, as shown by a succession of forest types ranging from white birch ( Betula papyrifera Marsh.) to spruce–fir types. Absence of surficial charcoal older than 300 years suggests that high-altitude forests of the RFL area were not subjected to a constant fire regime. It is possible that recent fires were caused by human activity.
Modern incursions of tropical Radiolaria into the Arctic Ocean
Authors: Bjørklund Kjell R. , Kruglikova Svetlana B. , Anderson O. Roger
Published: July 2012

Abstract. Plankton samples obtained by the Norwegian Polar Institute (August, 2010) in an area north of Svalbard contained an unusual abundance of tropical and subtropical radiolarian taxa (98 in 145 total observed taxa), not typically found at these high latitudes. A detailed analysis of the composition and abundance of these Radiolaria suggests that a pulse of warm Atlantic water entered the Norwegian Sea and finally entered into the Arctic Ocean, where evidence of both juvenile and adult forms suggests they may have established viable populations. Among radiolarians in general, this may be a good example of ecotypic plasticity. Radiolaria, with their high species number and characteristic morphology, can serve as a useful monitoring tool for pulses of warm water into the Arctic Ocean. Further analyses should be followed up in future years to monitor the fate of these unique plankton assemblages and to determine variation in northward distribution and possible penetration into the polar basin. The fate of this tropical fauna (persistence, disappearance, or genetic intermingling with existing taxa) is presently unknown. The current event may not be unique, nor a consequence of global warming, because analyses of sediment samples suggest that several natural pulses of warm water of this kind occurred in the prior century and, indeed, there may be more in years to come.
Cloud mobile gaming
Authors: Wang Shaoxuan , Dey Sujit
Published: July 2012

With the evolution of mobile devices and networks, and the growing trend of mobile Internet access, rich multi-player gaming using mobile devices, similar to PC-based Internet games, has tremendous potential and interest. However, the current client-server architecture for PC-based Internet games, where most of the storage and computational burden of the game lies with the client device, does not work with mobile devices, constraining mobile gaming to either downloadable, single player games, or very light non-interactive versions of the rich multi-player Internet games. In this article, we study a cloud server based mobile gaming approach, termed Cloud Mobile Gaming (CMG), where the burden of executing the gaming engine is put on cloud servers, and the mobile devices just communicate the users' gaming commands to the servers. We analyze the factors affecting the Quality of user Experience (QoE) using the CMG approach, including the game genres, video settings, the conditions of server and client, and the conditions of the wireless network. A Mobile Gaming User Experience (MGUE) model is developed and validated through controlled subjective testing. We also develop a prototype for in-service measuring MGUE, and then use it to characterize user experience achievable using the CMG approach in a mobile cellular network. The MGUE model developed and validated in this article will be helpful for researchers and service providers to develop and assess the performance of future cloud mobile gaming techniques and services.
Behavioral Ethics: Toward a Deeper Understanding of Moral Judgment and Dishonesty
Authors: Bazerman Max H. , Gino Francesca
Published: July 2012

Early research and teaching on ethics focused either on a moral development perspective or on philosophical approaches and used a normative approach by focusing on the question of how people should act when resolving ethical dilemmas. In this article, we briefly describe the traditional approach to ethics and then present a (biased) review of the behavioral approach to ethics. We define behavioral ethics as the study of systematic and predictable ways in which individuals make ethical decisions and judge the ethical decisions of others when these decisions are at odds with intuition and the benefits of the broader society. By focusing on a descriptive rather than a normative approach to ethics, behavioral ethics is better suited than traditional approaches to addressing the increasing demand from society for a deeper understanding of what causes even good people to cross ethical boundaries.
Ocean Acidification and Coral Reefs: Effects on Breakdown, Dissolution, and Net Ecosystem Calcification
Authors: Andersson Andreas J. , Gledhill Dwight
Published: July 2012

The persistence of carbonate structures on coral reefs is essential in providing habitats for a large number of species and maintaining the extraordinary biodiversity associated with these ecosystems. As a consequence of ocean acidification (OA), the ability of marine calcifiers to produce calcium carbonate (CaCO3) and their rate of CaCO3 production could decrease while rates of bioerosion and CaCO3 dissolution could increase, resulting in a transition from a condition of net accretion to one of net erosion. This would have negative consequences for the role and function of coral reefs and the eco-services they provide to dependent human communities. In this article, we review estimates of bioerosion, CaCO3 dissolution, and net ecosystem calcification (NEC) and how these processes will change in response to OA. Furthermore, we critically evaluate the observed relationships between NEC and seawater aragonite saturation state (Ωa). Finally, we propose that standardized NEC rates combined with observed changes in the ratios of dissolved inorganic carbon to total alkalinity owing to net reef metabolism may provide a biogeochemical tool to monitor the effects of OA in coral reef environments.
Role of the Gut in Lipid Homeostasis
Authors: Abumrad Nada A. , Davidson Nicholas O.
Published: July 2012

Intestinal lipid transport plays a central role in fat homeostasis. Here we review the pathways regulating intestinal absorption and delivery of dietary and biliary lipid substrates, principally long-chain fatty acid, cholesterol, and other sterols. We discuss the regulation and functions of CD36 in fatty acid absorption, NPC1L1 in cholesterol absorption, as well as other lipid transporters including FATP4 and SRB1. We discuss the pathways of intestinal sterol efflux via ABCG5/G8 and ABCA1 as well as the role of the small intestine in high-density lipoprotein (HDL) biogenesis and reverse cholesterol transport. We review the pathways and genetic regulation of chylomicron assembly, the role of dominant restriction points such as microsomal triglyceride transfer protein and apolipoprotein B, and the role of CD36, l-FABP, and other proteins in formation of the prechylomicron complex. We will summarize current concepts of regulated lipoprotein secretion (including HDL and chylomicron pathways) and include lessons learned from families with genetic mutations in dominant pathways (i.e., abetalipoproteinemia, chylomicron retention disease, and familial hypobetalipoproteinemia). Finally, we will provide an integrative view of intestinal lipid homeostasis through recent findings on the role of lipid flux and fatty acid signaling via diverse receptor pathways in regulating absorption and production of satiety factors.
Summary of Reported Whale-Vessel Collisions in Alaskan Waters
Authors: Neilson Janet L. , Gabriele Christine M. , Jensen Aleria S. , Jackson Kaili , Straley Janice M.
Published: July 2012

Here we summarize 108 reported whale-vessel collisions in Alaska from 1978–2011, of which 25 are known to have resulted in the whale's death. We found 89 definite and 19 possible/probable strikes based on standard criteria we created for this study. Most strikes involved humpback whales (86%) with six other species documented. Small vessel strikes were most common (<15 m, 60%), but medium (15–79 m, 27%) and large (≥80 m, 13%) vessels also struck whales. Among the 25 mortalities, vessel length was known in seven cases (190–294 m) and vessel speed was known in three cases (12–19 kn). In 36 cases, human injury or property damage resulted from the collision, and at least 15 people were thrown into the water. In 15 cases humpback whales struck anchored or drifting vessels, suggesting the whales did not detect the vessels. Documenting collisions in Alaska will remain challenging due to remoteness and resource limitations. For a better understanding of the factors contributing to lethal collisions, we recommend (1) systematic documentation of collisions, including vessel size and speed; (2) greater efforts to necropsy stranded whales; (3) using experienced teams focused on determining cause of death; (4) using standard criteria for validating collision reports, such as those presented in this paper.
A Numerical Algorithm on the Computation of the Stationary Distribution of a Discrete Time Homogenous Finite Markov Chain
Authors: Zhao Di , Li Hongyi , Su Donglin
Published: July 2012

The transition matrix, which characterizes a discrete time homogeneous
Markov chain, is a stochastic matrix. A stochastic matrix is a special nonnegative matrix with each row summing up to 1. In this paper, we focus on the computation of the
stationary distribution of a transition matrix from the viewpoint of the Perron vector
of a nonnegative matrix, based on which an algorithm for the stationary distribution
is proposed. The algorithm can also be used to compute the Perron root and the
corresponding Perron vector of any nonnegative irreducible matrix. Furthermore, a
numerical example is given to demonstrate the validity of the algorithm.
Comparing Melanoma Invasiveness in Dermatologist- versus Patient-Detected Lesions: A Retrospective Chart Review
Authors: Lamerson Cindy L. , Eaton Kristina , Sax Joel L. , Kashani-Sabet Mohammed
Published: July 2012

This study examined whether patient-identified melanomas were more advanced than dermatologist-identified tumors at routine clinic visits, and whether a personal or family history of skin cancer was associated with patterns of detection. A retrospective chart review was performed on melanoma patients (N=201) in a private dermatology clinic. Variables included age, gender, pattern of detection (i.e., patient or a board certified dermatologist), personal or family history of skin cancer, skin type, and previous sun exposure, as well as tumor location and severity. Dermatologist-diagnosed melanomas were less invasive (P<0.0005), and more likely present on the chest, back, and legs (P<0.01). Conversely, patient-identified lesions were more likely to occur on the face, neck and scalp, be associated with younger patients, and a family history of melanoma, but not other types of skin cancer (P<0.01). In a post-hoc analysis examining these factors as predictors of tumor invasiveness, only diagnostic source was significant. Specifically, dermatologist-identified tumors were significantly less invasive than patient-identified tumors. Although age, family history, and tumor location played roles in the early detection of melanomas, the most important factor was diagnostic source. Thus, board-certified dermatologists play a key role in the early detection of malignant melanoma.
Malignant Mesothelioma of the Tunica Vaginalis: Presenting with Intermittent Scrotal Pain and Hydrocele
Authors: Esen Tarık , Acar Omer , Peker Kamil , Sarman Kemal , Musaoglu Ahmet , Tefekli Ahmet
Published: July 2012

Paratesticular mesotheliomas are very rare tumors. In this paper, we present the management of a 38-year-old male patient with paratesticular malignant mesothelioma who was initially misdiagnosed and treated as recurrent epididymitis. After the final pathology report defining paratesticular mesothelioma during scrotal exploration, he underwent radical orchiectomy and hemiscrotal excision as a complementary, secondary procedure. His metastatic workup did not show any dissemination. Therefore, he did not receive any adjuvant treatment and remained disease-free for more than 2 years.
Hybrid Method with Perturbation for Lipschitzian Pseudocontractions
Authors: Ceng Lu-Chuan , Wen Ching-Feng
Published: July 2012

Assume that F is a nonlinear operator which is Lipschitzian and strongly monotone on a nonempty closed convex subset C of a real Hilbert space H. Assume also that Ω is the intersection of the fixed point sets of a finite number of Lipschitzian pseudocontractive self‐mappings on C. By combining hybrid steepest‐descent method, Mann’s iteration method and projection method, we devise a hybrid iterative algorithm with perturbation F, which generates two sequences from an arbitrary initial point x0 ∈ H. These two sequences are shown to converge in norm to the same point PΩx0 under very mild assumptions.
Nonoscillatory Solutions of Second‐Order Differential Equations without Monotonicity Assumptions
Authors: Wang Lianwen , McKee Rhonda
Published: July 2012

The continuability, boundedness, monotonicity, and asymptotic properties of nonoscillatory solutions for a class of second‐order nonlinear differential equations are discussed without monotonicity assumption for function g. It is proved that all solutions can be extended to infinity, are eventually monotonic, and can be classified into disjoint classes that are fully characterized in terms of several integral conditions. Moreover, necessary and sufficient conditions for the existence of solutions in each class and for the boundedness of all solutions are established.
Modeling of Output Characteristics of a UV Cu+ Ne‐CuBr Laser
Authors: Gocheva-Ilieva Snezhana Georgieva , Voynikova Desislava Stoyanova , Iliev Iliycho Petkov
Published: July 2012

This paper examines experiment data for a Ne‐CuBr UV copper ion laser excited by longitudinal pulsed discharge emitting in multiline regime. The flexible multivariate adaptive regression splines (MARSs) method has been used to develop nonparametric regression models describing the laser output power and service life of the devices. The models have been constructed as explicit functions of 9 basic input laser characteristics. The obtained models account for local nonlinearities of the relationships within the various multivariate subregions. The built best MARS models account for over 98% of data. The models are used to estimate the investigated output laser characteristics of existing UV lasers. The capabilities for using the models in predicting existing and future experiments have been demonstrated. Specific analyses have been presented comparing the models with actual experiments. The obtained results are applicable for guiding and planning the engineering experiment. The modeling methodology can be applied for a wide range of similar lasers and laser devices.
Central Neuropathic Pain in a Patient with Multiple Sclerosis Treated Successfully with Topical Amitriptyline
Authors: Kopsky David J. , Liebregts Remko , Keppel Hesselink Jan M.
Published: July 2012

Central neuropathic pain in patients with multiple sclerosis (MS) is a common debilitating symptom, which is mostly treated with tricyclic antidepressants or antiepileptics. Unfortunately, the use of these drugs is often limited due to adverse events. We investigated the analgesic effect of topical amitriptyline 5% and 10% cream in a patient with central neuropathic pain due to MS. The analgesic effect of topical amitriptyline cream on neuropathic pain was dose related. To evaluate whether this analgesic effect is due to the active compound or placebo, we conducted a double-blind placebo-controlled n-of-1 study with amitriptyline 5% cream and placebo. The instruction was to alternate the creams every week following the pattern ABAB, with an escape possibility of amitriptyline 10% cream. The result was a complete pain reduction after application of cream B, while most of the time cream A did not reduce the pain. The patient could correctly unblind both creams, determining B as active. She noted that in the week of using the active cream no allodynia was present, with a carryover effect of one day.
Open-Water Thrust and Torque Predictions of a Ducted Propeller System with a Panel Method
Authors: Baltazar J. , Falcão de Campos J. A. C. , Bosschers J.
Published: July 2012

This paper discusses several modelling aspects that are important for the performance predictions of a ducted propulsor with a low-order Panel Method. The aspects discussed are the alignment of the wake geometry, the influence of the duct boundary layer on the wake pitch, and the influence of a transpiration velocity through the gap. The analysis is carried out for propeller Ka4-70 operating without and inside a modified duct 19A, in which the rounded trailing edge is replaced by a sharp trailing edge. Experimental data for the thrust and torque are used to validate the numerical results. The pitch of the tip vortex is found to have a strong influence on the propeller and duct loads. A good agreement with the measurements is achieved when the wake alignment is corrected for the presence of the duct boundary layer.
Synthesis, Characterization, and Applications of ZnO Nanowires
Authors: Zhang Yangyang , Ram Manoj K. , Stefanakos Elias K. , Goswami D. Yogi
Published: July 2012

ZnO nanowires (or nanorods) have been widely studied due to their unique material properties and remarkable performance in electronics, optics, and photonics. Recently, photocatalytic applications of ZnO nanowires are of increased interest in environmental protection applications. This paper presents a review of the current research of ZnO nanowires (or nanorods) with special focus on photocatalysis. We have reviewed the semiconducting photocatalysts and discussed a variety of synthesis methods of ZnO nanowires and their corresponding effectiveness in photocatalysis. We have also presented the characterization of ZnO nanowires from the literature and from our own measurements. Finally, a wide range of uses of ZnO nanowires in various applications is highlighted in this paper.
Visual Cortex Plasticity: A Complex Interplay of Genetic and Environmental Influences
Authors: Maya-Vetencourt José Fernando , Origlia Nicola
Published: July 2012

The central nervous system architecture is highly dynamic and continuously modified by sensory experience through processes of neuronal plasticity. Plasticity is achieved by a complex interplay of environmental influences and physiological mechanisms that ultimately activate intracellular signal transduction pathways regulating gene expression. In addition to the remarkable variety of transcription factors and their combinatorial interaction at specific gene promoters, epigenetic mechanisms that regulate transcription have emerged as conserved processes by which the nervous system accomplishes the induction of plasticity. Experience-dependent changes of DNA methylation patterns and histone posttranslational modifications are, in fact, recruited as targets of plasticity-associated signal transduction mechanisms. Here, we shall concentrate on structural and functional consequences of early sensory deprivation in the visual system and discuss how intracellular signal transduction pathways associated with experience regulate changes of chromatin structure and gene expression patterns that underlie these plastic phenomena. Recent experimental evidence for mechanisms of cross-modal plasticity following congenital or acquired sensory deprivation both in human and animal models will be considered as well. We shall also review different experimental strategies that can be used to achieve the recovery of sensory functions after long-term deprivation in humans.
Optimizing Dendritic Cell-Based Immunotherapy: Tackling the Complexity of Different Arms of the Immune System
Authors: Van Brussel Ilse , Berneman Zwi N. , Cools Nathalie
Published: July 2012

Earlier investigations have revealed a surprising complexity and variety in the range of interaction between cells of the innate and adaptive immune system. Our understanding of the specialized roles of dendritic cell (DC) subsets in innate and adaptive immune responses has been significantly advanced over the years. Because of their immunoregulatory capacities and because very small numbers of activated DC are highly efficient at generating immune responses against antigens, DCs have been vigorously used in clinical trials in order to elicit or amplify immune responses against cancer and chronic infectious diseases. A better insight in DC immunobiology and function has stimulated many new ideas regarding the potential ways forward to improve DC therapy in a more fundamental way. Here, we discuss the continuous search for optimal in vitro conditions in order to generate clinical-grade DC with a potent immunogenic potential. For this, we explore the molecular and cellular mechanisms underlying adequate immune responses and focus on most favourable DC culture regimens and activation stimuli in humans. We envisage that by combining each of the features outlined in the current paper into a unified strategy, DC-based vaccines may advance to a higher level of effectiveness.
Nephron-Sparing Surgery for Adenocarcinoma in a Renal Allograft
Authors: Vázquez Alonso Fernando , Cardozo Rodríguez Enrique , Puche Sanz Ignacio , Flores Martin Jose Francisco , Molina Hernandez Jose Miguel , Berrio Campos Raquel , Vicente Prados Javier , Medina Benitez Antonio , Cózar Olmo Jose Manuel
Published: July 2012

The incidence of malignant tumors in recipients of renal allografts is higher than in the general population. Renal cell carcinoma (RCC) accounts for 4.6% of the tumors in transplanted patients; of them, only 10% are found in transplanted kidneys. Transplantectomy has always been the usual treatment. However, during the last years, nephron-sparing surgery of the allograft is more frequently done in well-selected cases, and therefore dialysis can be avoided. We report the case of a 37-year-old female patient with renal transplant, diagnosed with a 4.5 cm tumor in the lower pole of the renal allograft. The patient underwent partial nephrectomy successfully. Six years after surgery, there is no evidence of recurrence of the disease and the patient maintains an adequate renal function.
Neural Network Compensation Control for Output Power Optimization of Wind Energy Conversion System Based on Data-Driven Control
Authors: Li T. , Feng A. J. , Zhao L.
Published: July 2012

Due to the uncertainty of wind and because wind energy conversion systems (WECSs) have strong nonlinear characteristics, accurate model of the WECS is difficult to be built. To solve this problem, data-driven control technology is selected and data-driven controller for the WECS is designed based on the Markov model. The neural networks are designed to optimize the output of the system based on the data-driven control system model. In order to improve the efficiency of the neural network training, three different learning rules are compared. Analysis results and SCADA data of the wind farm are compared, and it is shown that the method effectively reduces fluctuations of the generator speed, the safety of the wind turbines can be enhanced, the accuracy of the WECS output is improved, and more wind energy is captured.
Spatially Nonhomogeneous Periodic Solutions in a Delayed Predator‐Prey Model with Diffusion Effects
Authors: Zhang Jia-Fang
Published: July 2012

This paper is concerned with a delayed predator‐prey diffusion model with Neumann boundary conditions. We study the asymptotic stability of the positive constant steady state and the conditions for the existence of Hopf bifurcation. In particular, we show that large diffusivity has no effect on the Hopf bifurcation, while small diffusivity can lead to the fact that spatially nonhomogeneous periodic solutions bifurcate from the positive constant steady‐state solution when the system parameters are all spatially homogeneous. Meanwhile, we study the properties of the spatially nonhomogeneous periodic solutions applying normal form theory of partial functional differential equations (PFDEs).
Estimation of Insulin Resistance in Mexican Adults by the [13C]Glucose Breath Test Corrected for Endogenous Total CO2Production
Authors: Ibarra-Pastrana Erika , Candia Plata Maria del Carmen , Alvarez Gerardo , Valencia Mauro E.
Published: July 2012

Objective. To evaluate the efficacy of the [13C]glucose breath test for measuring insulin resistance in Mexican adults with different glycemic states.Research Design and Methods. Fifty-eight adults underwent a [13C]glucose breath test with simultaneous measurement of total CO2production by indirect calorimetry, at baseline and 90 minutes after the ingestion of 15 g of dextrose and 25 mg of [13C]glucose. HOMA was used as a marker of insulin resistance.Results. We found an inverse correlation between HOMA and the breath testδ13CO2(‰),r=-0.41(P=0.001). After adjusting for total CO2production, correlations between HOMA and fasting glucose were less strong but remained significant. An ROC curve was constructed usingδ13CO2(‰) and HOMA values; the cut-off point was 9.99‰δ13CO2, corresponding to a sensitivity of 80.0 (95% CI: 51.9, 95.7) and a specificity of 67.4 (95% CI: 51.5, 80.9).Conclusions. The [13C]glucose breath test is a simple noninvasive procedure but was not sufficiently robust for an accurate diagnosis of insulin resistance. Our findings suggest that the test might be helpful in identifying individuals who are not IR, which in turn may contribute to improved diabetes prevention.
PGI2as a Regulator of Inflammatory Diseases
Authors: Dorris Stacy L. , Peebles R. Stokes
Published: July 2012

Prostacyclin, or PGI2, is an end product derived from the sequential metabolism of arachidonic acid via cyclooxygenase and PGI synthase (PGIS). The receptor for PGI2, IP, can be found on a variety of cell types and signaling through this receptor exhibits broad physiological effects. Historically, PGI2has been understood to play a role in cardiovascular health, specifically having powerful vasodilatory effects via relaxation of smooth muscle and inhibiting of platelet aggregation. For these reasons, PGI2has a long history of use for the treatment of pulmonary arterial hypertension (PAH). Only recently, its importance as an immunomodulatory agent has been investigated. PGI2regulates both the innate and adaptive immune systems and its effects are, for the most part, thought to be anti-inflammatory or immunosuppressive in nature, which may have implications for its further clinical use.
Landslide Susceptibility Assessment in Vietnam Using Support Vector Machines, Decision Tree, and Naïve Bayes Models
Authors: Tien Bui Dieu , Pradhan Biswajeet , Lofman Owe , Revhaug Inge
Published: July 2012

The objective of this study is to investigate and compare the results of three data mining approaches, the support vector machines (SVM), decision tree (DT), and Naïve Bayes (NB) models for spatial prediction of landslide hazards in the Hoa Binh province (Vietnam). First, a landslide inventory map showing the locations of 118 landslides was constructed from various sources. The landslide inventory was then randomly partitioned into 70% for training the models and 30% for the model validation. Second, ten landslide conditioning factors were selected (i.e., slope angle, slope aspect, relief amplitude, lithology, soil type, land use, distance to roads, distance to rivers, distance to faults, and rainfall). Using these factors, landslide susceptibility indexes were calculated using SVM, DT, and NB models. Finally, landslide locations that were not used in the training phase were used to validate and compare the landslide susceptibility maps. The validation results show that the models derived using SVM have the highest prediction capability. The model derived using DT has the lowest prediction capability. Compared to the logistic regression model, the prediction capability of the SVM models is slightly better. The prediction capability of the DT and NB models is lower.
Catalytic and Noncatalytic Conversion of Methane to Olefins and Synthesis Gas in an AC Parallel Plate Discharge Reactor
Authors: Khodagholi Mohammad Ali , Irani Mohammad
Published: July 2012

Direct conversion of methane to ethylene, acetylene, and synthesis gas at ambient pressure and temperature in a parallel plate discharge reactor was investigated. The experiments were carried out using a quartz reactor of outer diameter of 9 millimeter and a driving force of ac current of 50 Hz. The input power to the reactor to establish a stable gas discharge varied from 9.6 to maximum 15.3 watts (w). The effects of ZSM5, Fe–ZSM5, and Ni–ZSM5 catalysts combined with corona discharge for conversion of methane to more valued products have been addressed. It was found that in presence or absence of a catalyst in gas discharge reactor, the rate of methane and oxygen conversion increased upon higher input power supplied to the reactor. The effect of Fe–ZSM5 catalyst combined with gas discharge plasma yields C2 hydrocarbons up to 21.9%, which is the highest productions of C2 hydrocarbons in this work. The effect of combined Ni–ZSM5 and gas discharge plasma was mainly production of synthesis gas. The advantage of introducing ZSM5 to the plasma zone was increase in synthesis gas and acetylene production. The highest energy efficiency was 0.22 mmol/kJ, which belongs to lower rate of energy injection to the reactor.
Cancer-Associated Fibroblasts Induce Matrix Metalloproteinase–Mediated Cetuximab Resistance in Head and Neck Squamous Cell Carcinoma Cells
Authors: Johansson Ann-Charlotte , Ansell Anna , Jerhammar Fredrik , Lindh Maja Bradic , Grénman Reidar , Munck-Wikland Eva , Östman Arne , Roberg Karin
Published: July 2012

A growing body of evidence suggests that components of the tumor microenvironment, including cancer-associated fibroblasts (CAF), may modulate the treatment sensitivity of tumor cells. Here, we investigated the possible influence of CAFs on the sensitivity of head and neck squamous cell carcinoma (HNSCC) cell lines to cetuximab, an antagonistic epidermal growth factor receptor (EGFR) antibody. Cetuximab treatment caused a reduction in the proliferation rate of HNSCC cell lines, whereas the growth of HNSCC-derived CAF cultures was unaffected. When tumor cells were cocultured with CAFs in a transwell system, the cetuximab-induced growth inhibition was reduced, and a complete protection from growth inhibition was observed in one of the tumor cell lines investigated. Media that had been conditioned by CAFs offered protection from cetuximab treatment in a concentration-dependent manner, suggesting that the resistance to treatment was mediated by CAF-derived soluble factors. The coculture of HNSCC cell lines with CAFs resulted in an elevated expression of matrix metalloproteinase-1 (MMP-1) in both the tumor cells and CAFs. Moreover, the CAF-induced resistance was partly abolished by the presence of an MMP inhibitor. However, CAFs treated with siRNA targeting MMP-1 still protected tumor cells from cetuximab treatment, suggesting that several MMPs may cooperate to facilitate resistance or that the protective effect is mediated by another member of the MMP family. These results identify a novel CAF-dependent modulation of cetuximab sensitivity and suggest that inhibiting MMPs may improve the effects of EGFR-targeted therapy. Mol Cancer Res; 10(9); 1158–68. ©2012 AACR.
Microwave Properties of Ice-Phase Hydrometeors for Radar and Radiometers: Sensitivity to Model Assumptions
Authors: Johnson Benjamin T. , Petty Grant W. , Skofronick-Jackson Gail
Published: July 2012

A simplified framework is presented for assessing the qualitative sensitivities of computed microwave properties, satellite brightness temperatures, and radar reflectivities to assumptions concerning the physical properties of ice-phase hydrometeors. Properties considered included the shape parameter μ of a gamma size distribution and the melted-equivalent mass median diameter D0, the particle density, the dielectric mixing formula, and the choice of complex index of refraction for ice. These properties are examined for selected radiometer frequencies of 18.7, 36.5, 89.0, and 150.0 GHz and radar frequencies at 2.8, 13.4, 35.6, and 94.0 GHz—consistent with existing and planned remote sensing instruments. Passive and active microwave observables of ice particles are found to be extremely sensitive to the D0 of the size distribution. Similar large sensitivities are found for variations in the ice volume fraction whenever the geometric mass median diameter exceeds approximately ⅛th of the wavelength. At 94 GHz the two-way path-integrated attenuation is potentially large for dense/compact particles. The distribution parameter μ has a comparatively weak effect on any observable: less than 1–2 K in brightness temperature and a maximum of 2.7 dB (S band only) in the effective radar reflectivity. Reversal of the roles of ice and air in the Maxwell Garnett dielectric mixing formula leads to a substantial change in both microwave brightness temperature (~10 K) and radar reflectivity (approximately 2 dB across all frequencies). The choice of the complex index of refraction of ice can produce a 3%–4% change in the brightness temperature depression.
Climate Warming–Related Strengthening of the Tropical Hydrological Cycle
Authors: Zahn Matthias , Allan Richard P.
Published: July 2012

The authors estimate climate warming–related twenty-first-century changes of moisture transports from the descending into the ascending regions in the tropics. Unlike previous studies that employ time and space averaging, here homogeneous high horizontal and vertical resolution data from an Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC AR4) climate model are used. This allows for estimating changes in much greater detail (e.g., the estimation of the distribution of ascending and descending regions, changes in the vertical profile, and separating changes of the inward and outward transports). Low-level inward and midlevel outward moisture transports of the convective regions in the tropics are found to increase in a simulated anthropogenically warmed climate as compared to a simulated twentieth-century atmosphere, indicating an intensification of the hydrological cycle. Since an increase of absolute inward transport exceeds the absolute increase of outward transport, the resulting budget is positive, meaning that more water is projected to converge in the moist tropics. The intensification is found mainly to be due to the higher amount of water in the atmosphere, while the contribution of weakening wind counteracts this response marginally. In addition the changing statistical properties of the vertical profile of the moisture transport are investigated and the importance of the substantial outflow of moisture from the moist tropics at midlevels is demonstrated.