bluuebunny/crossref_metadata_2025 huggingface dataset:
Constructing a Small-Region DSGE Model
Authors: Tamegawa Kenichi
Published: March 2013

This paper constructs a tractable dynamic stochastic general equilibrium (DSGE) model of a regional economy that is considered small because it does not affect its national economy. To examine properties of our small-region DSGE model, we conduct several numerical simulations. Notably, fiscal expansion in our model is larger than that in standard DSGE models. This is because the increase in regional output does not raise interest rates, and this leads to the crowding-in effects of investment.
Simulating the Emergence of Mutations and Their Subsequent Evolution in an Age-Structured Stochastic Self-Regulating Process with Two Sexes
Authors: Mode Charles J. , Sleeman Candace K. , Raj Towfique
Published: March 2013

The stochastic process under consideration is intended to be not only part of the working paradigm of evolutionary and population genetics but also that of applied probability and stochastic processes with an emphasis on computer intensive methods. In particular, the process is an age-structured self-regulating multitype branching process with a genetic component consisting of an autosomal locus with two alleles for females and males. It is within this simple context that mutation will be quantified in terms of probabilities that a given allele mutates to the other per meiosis. But, unlike many models that are currently being used in mathematical population genetics, in which natural selection is often characterized in terms of parameters called fitness by genotype or phenotype, in this paper the parameterization of submodules of the model provides a framework for characterizing natural selection in terms of some of its components. One of these modules consists of reproductive success that is quantified in terms of the total expected number of offspring a female contributes to the population throughout her fertile years. Another component consists of survival probabilities that characterize an individual’s ability to compete for limited environmental resources. A third module consists of a parametric function that expresses the probabilities of survival in a birth cohort of individuals by age for both females and males. A forth module of the model as an acceptance matrix of conditional probabilities such female may show a preference for the genotype or phenotype as her male sexual partner. It is assumed that any force of natural selection acts at the level of the three genotypes under consideration for each sex. By assigning values of the parameters in each of the modules under consideration, it is possible to conduct Monte Carlo simulation experiments designed to study the effects of each component of selection separately or in any combination on a population evolving from a given initial population over some specified period of time.
Dynkin's Games and Israeli Options
Authors: Kifer Yuri
Published: March 2013

We start by briefly surveying a research on optimal stopping games since their introduction by Dynkin more than 40 years ago. Recent renewed interest to Dynkin’s games is due, in particular, to the study of Israeli (game) options introduced in 2000. We discuss the work on these options and related derivative securities for the last decade. Among various results on game options we consider error estimates for their discrete approximations, swing game options, game options in markets with transaction costs, and other questions.
Consensus of the Distributed Varying Scale Wireless Sensor Networks
Authors: Mou Jinping , Zhou Wuneng , Wang Tianbo , Ji Chuan , Tong Dongbing
Published: March 2013

Consensus problems are investigated for a type of the distributed varying scale wireless sensor network (VSWSN), where the scale of the network is increasing or decreasing due to the new nodes joining in or the invalid nodes quitting from WSN, respectively. In order to demonstrate the communicating behaviors more realistic, we offer the node attached component sequence for each valid node under the general sleep algorithm. Based on the component sequences, several concepts, such as the local limited intersection connection (LLI connection) and the global limited intersection connection (GLI connection), are provided to display the connectivity of the varying topology. Under certain conditions, the designed protocol ensures that all sensors arrive at the component consensus or the global consensus if the communicating graph is LLI connected or GLI connected, respectively. By the basic theoretical analysis, several consensus criterions are obtained. In the meanwhile, the consensus regions are investigated. The numerical example shows the reliability of the proposed results.
Brazilein fromCaesalpinia sappanL. Antioxidant Inhibits Adipocyte Differentiation and Induces Apoptosis through Caspase-3 Activity and Anthelmintic Activities againstHymenolepis nanaandAnisakis simplex
Authors: Liang Chia-Hua , Chan Leong-Perng , Chou Tzung-Han , Chiang Feng-Yu , Yen Chuan-Min , Chen Pin-Ju , Ding Hsiou-Yu , Lin Rong-Jyh
Published: March 2013

Brazilein, a natural, biologically active compound fromCaesalpinia sappanL., has been shown to exhibit anti-inflammatory and antioxidant properties and to inhibit the growth of several cancer cells. This study verifies the antioxidant and antitumor characteristics of brazilein in skin cancer cells and is the first time to elucidate the inhibition mechanism of adipocyte differentiation, cestocidal activities againstHymenolepis nana, and reduction of spontaneous movement inAnisakis simplex. Brazilein exhibits an antioxidant capacity as well as the ability to scavenge DPPH•and ABTS•+free radicals and to inhibit lipid peroxidation. Brazilein inhibited intracellular lipid accumulation during adipocyte differentiation in 3T3-L1 cells and suppressed the induction of peroxisome proliferator-activated receptorγ(PPARγ), the master regulator of adipogenesis, suggesting that brazilein presents the antiobesity effects. The toxic effects of brazilein were evaluated in terms of cell viability, induction of apoptosis, and the activity of caspase-3 in BCC cells. The inhibition of the growth of skin cancer cells (A431, BCC, and SCC25) by brazilein is greater than that of human skin malignant melanoma (A375) cells, mouse leukemic monocyte macrophage (RAW 264.7 cells), and noncancerous cells (HaCaT and BNLCL2 cells). The anthelmintic activities of brazilein againstHymenolepis nanaare better than those ofAnisakis simplex.
Evaluation of the Antibacterial and Antifungal Potential of Peltophorum africanum: Toxicological Effect on Human Chang Liver Cell Line
Authors: Okeleye Benjamin I. , Mkwetshana Noxolo T. , Ndip Roland N.
Published: March 2013

We assessed the in vitro antimicrobial activity of Peltophorum africanum by means of the agar well and macrodilution methods. The toxicity on a normal human liver cell (Chang liver cell) was determined using the CellTiter‐Blue cell viability assay, and the compounds contained in the fractions were identified using GC‐MS. Zone diameter of inhibition of the extract ranged from 12.5 ± 0.7  to  32 ± 2.8 mm for bacteria and from  7.5 ± 0.7  to  26.4 ± 3.4 mm for yeast. Marked activity of the extract was observed against Plesiomonas shigelloides ATCC 51903, with MIC and MLC values of 0.15625 and 0.3125 mg/mL, respectively. The extract was both bactericidal (MICindex ≤ 2) and bacteriostatic/fungistatic (MICindex > 2) in activity. Lethal dose at 50 (LD50) showed 82.64 ± 1.40 degree of toxicity at 24 hrs, and 95 percentile of cell death dose activity ranged from log 3.12 ± 0.01  to  4.59 ± 0.03. The activity of the eight fractions tested ranged from 1.0 ± 0.5  to  3.7 ± 1.6 mg/mL (IC50) and from  2.1 ± 0.8  to  6.25 ± 0 mg/mL (IC90). The extract was toxic to human Chang liver cell lines.
Positive Periodic Solutions in a Discrete Time Three Species Competition System
Authors: Xu Changjin , Wu Yusen
Published: March 2013

A periodic discrete time three species competition system is investigated. With the aid of differential equations with piecewise constant arguments, a discrete analogue of continuous nonautonomous three species competition system is proposed. By using Gaines and Mawhin's continuation theorem of coincidence degree theory, sufficient conditions for the existence of positive periodic solutions of the model are obtained.
From 2D to 3D: Construction of a 3D Parametric Model for Detection of Dental Roots Shape and Position from a Panoramic Radiograph—A Preliminary Report
Authors: Mazzotta Laura , Cozzani Mauro , Razionale Armando , Mutinelli Sabrina , Castaldo Attilio , Silvestrini-Biavati Armando
Published: March 2013

Objectives. To build a 3D parametric model to detect shape and volume of dental roots, from a panoramic radiograph (PAN) of the patient.Materials and Methods. A PAN and a cone beam computed tomography (CBCT) of a patient were acquired. For each tooth, various parameters were considered (coronal and root lengths and widths): these were measured from the CBCT and from the PAN. Measures were compared to evaluate the accuracy level of PAN measurements. By using a CAD software, parametric models of an incisor and of a molar were constructed employing B-spline curves and free-form surfaces. PAN measures of teeth 2.1 and 3.6 were assigned to the parametric models; the same two teeth were segmented from CBCT. The two models were superimposed to assess the accuracy of the parametric model.Results. PAN measures resulted to be accurate and comparable with all other measurements. From model superimposition the maximum error resulted was 1.1 mm on the incisor crown and 2 mm on the molar furcation.Conclusion. This study shows that it is possible to build a 3D parametric model starting from 2D information with a clinically valid accuracy level. This can ultimately lead to a crown-root movement simulation.
Robust Myocardial Motion Tracking for Echocardiography: Variational Framework Integrating Local-to-Global Deformation
Authors: Ahn Chi Young
Published: March 2013

This paper proposes a robust real-time myocardial border tracking algorithm for echocardiography. Commonly, after an initial contour of LV border is traced at one or two frames from the entire cardiac cycle, LV contour tracking is performed over the remaining frames. Among a variety of tracking techniques, optical flow method is the most widely used for motion estimation of moving objects. However, when echocardiography data is heavily corrupted in some local regions, the errors bring the tracking point out of the endocardial border, resulting in distorted LV contours. This shape distortion often occurs in practice since the data acquisition is affected by ultrasound artifacts, dropouts, or shadowing phenomena of cardiac walls. The proposed method is designed to deal with this shape distortion problem by integrating local optical flow motion and global deformation into a variational framework. The proposed descent method controls the individual tracking points to follow the local motions of a specific speckle pattern, while their overall motions are confined to the global motion constraint being approximately an affine transform of the initial tracking points. Many real experiments show that the proposed method achieves better overall performance than conventional methods.
Noninvasive Characterisation of Foot Reflexology Areas by Swept Source-Optical Coherence Tomography in Patients with Low Back Pain
Authors: Dalal Krishna , Elanchezhiyan D. , Das Raunak , Dalal Devjyoti , Pandey Ravindra Mohan , Chatterjee Subhamoy , Upadhyay Ashish Datt , Maran V. Bharathi , Chatterjee Jyotirmoy
Published: March 2013

Objective. When exploring the scientific basis of reflexology techniques, elucidation of the surface and subsurface features of reflexology areas (RAs) is crucial. In this study, the subcutaneous features of RAs related to the lumbar vertebrae were evaluated by swept source-optical coherence tomography (SS-OCT) in subjects with and without low back pain (LBP).Methods. Volunteers without LBP (n=6(male : female = 1 : 1)) and subjects with LBP (n=15(male : female = 2 : 3)) were clinically examined in terms of skin colour (visual perception), localised tenderness (visual analogue scale) and structural as well as optical attributes as per SS-OCT. From each subject, 6 optical tomograms were recorded from equidistant transverse planes along the longitudinal axis of the RAs, and from each tomogram, 25 different spatial locations were considered for recording SS-OCT image attributes. The images were analysed with respect to the optical intensity distributions and thicknesses of different skin layers by using AxioVision Rel. 4.8.2 software. The SS-OCT images could be categorised into 4 pathological grades (i.e., 0, 1, 2, and 3) according to distinctness in the visible skin layers.Results. Three specific grades for abnormalities in SS-OCT images were identified considering gradual loss of distinctness and increase in luminosity of skin layers. Almost 90.05% subjects were of mixed type having predominance in certain grades.Conclusion. The skin SS-OCT system demonstrated a definite association of the surface features of healthy/unhealthy RAs with cutaneous features and the clinical status of the lumbar vertebrae.
Immune Reconstitution and Risk of Hodgkin's Lymphoma among a Sample of HIV-Infected Male Veterans
Authors: M Kowalkowski , E Chiao
Published: March 2013

Purpose: In contrast to certain AIDS-defining cancers, the incidence of Hodgkin's lymphoma (HL) has increased since the introduction of combined antiretroviral therapy (cART). Although HIV-associated HL has been strongly linked to the Epstein-Barr virus, the causes for the increased incidence of HL in the cART era remain unclear. The aim of this study was to evaluate the effect of cART utilization and possible immune reconstitution inflammatory syndrome (IRIS), through monitoring the activity of immunologic measures (e.g., nadir CD4 prior to cART, recent CD4, percent of time with undetectable HIV viral load), on the incidence of HL among a sample of HIV-infected male veterans. Methods: We performed a retrospective cohort study utilizing data from the Veterans Affairs HIV Clinical Case Registry (VA-CCR) from 1985–2010. HL cases were identified using ICD-9 codes. Women were excluded due to low numbers. We also excluded individuals without identifiable CD4 or viral load measurement, no cART use, <90 days of follow-up, and prevalent HL cases occurring prior to or within 90 days of HIV diagnosis. We analyzed the relationship between immunologic measures associated with cART utilization and the incidence of HL, calculated in multivariable Poisson regression models adjusted for demographic and time-varying immunologic covariates. Results: The final sample included 31,596 cART users, contributing 288,968 person-years and 219 HL cases (IR = 76 per 100,000 person-years). In multivariable regression models, the risk of HL was higher among veterans with recent CD4 <200 copies/cell (IRR = 1.57, 95%CI = 1.05–2.34) and between 200–350 copies/cell (IRR = 1.68, 95%CI = 1.17–2.40), compared to individuals with >350 copies/cell. Also, HL risk was increased among veterans within 1 year (IRR = 2.38, 95%CI = 1.60–3.53) and 1–2 years (IRR = 1.89, 95%CI = 1.27–2.82) after cART initiation, compared to >2 years. Conclusion: Recent CD4 counts <350 copies/cell were associated with an increased risk of HL among cART users. Additionally, risk of HL was increased in the 2 years directly following cART initiation. Findings indicate an EBV-associated IRIS may function in HL development in HIV-infected individuals.
Lamination of the Lateral Geniculate Nucleus of Catarrhine Primates
Authors: de Sousa Alexandra A. , Sherwood Chet C. , Hof Patrick R. , Zilles Karl
Published: March 2013

The lateral geniculate nucleus (LGN) of catarrhine primates - with the exception of gibbons - is typically described as a 6-layered structure, comprised of 2 ventral magnocellular layers, and 4 dorsal parvocellular layers. The parvocellular layers of the LGN are involved in color vision. Therefore, it is hypothesized that a 6-layered LGN is a shared-derived trait among catarrhines. This might suggest that in gibbons the lack of further subdivisions of the parvocellular layers is a recent change, and could be related to specializations of visual information processing in this taxon. To address these hypotheses, the lamination of the LGN was investigated in a range of catarrhine species, including several taxa not previously described, and the evolution of the LGN was reconstructed using phylogenetic information. The findings indicate that while all catarrhine species have 4 parvocellular leaflets, two main patterns of LGN parvocellular lamination occur: 2 undivided parvocellular layers in some species, and 4 parvocellular leaflets (with occasional subleaflets) in other species. LGN size was not found to be related to lamination pattern. Both patterns were found to occur in divergent clades, which is suggestive of homoplasy within the catarrhines in LGN morphology.
The Incidence and Prognosis of Renal Dysfunction following Cardioversion of Atrial Fibrillation
Authors: Hellman Yaron , Cohen Matan J. , Leibowitz David , Loncar Sasa , Gozal David , Haviv Yosef S. , Haber Guy , Afifi Mohamad , Rosenheck Shimon , Lotan Chaim , Pollak Arthur , Gilon Dan
Published: March 2013

Objective: Limited data are available regarding the incidence and clinical impact of renal dysfunction following cardioversion of atrial fibrillation. The objective of this study was to assess the incidence and implications of renal dysfunction following cardioversion of atrial fibrillation. Methods: We conducted a nested case-control study to determine the incidence, timing, risk factors and outcome of atrial fibrillation cardioversion associated with renal dysfunction (AFCARD) in a tertiary medical center. Consecutive patients undergoing direct current cardioversion (DCCV) for atrial fibrillation in our institution during 2008-2009 with measurements of creatinine before and following cardioversion were included. AFCARD was defined as a rise in serum creatinine greater than 25% from baseline within a week following DCCV. Results: One hundred and twelve patients were included in the study, of whom 19 (17%) developed AFCARD. One patient required hemodialysis. Patients with AFCARD had a higher incidence of advanced heart failure, diabetes mellitus and were more frequently treated with digoxin and enoxaparin. Patients with AFCARD had a significantly decreased survival rate at 1 year (63 vs. 92%; p < 0.001). Conclusions: AFCARD is relatively common and is associated with increased mortality. These findings suggest a role for close surveillance of renal function following DCCV.
Endovascular Management of Arteriovenous Malformations of the Brain
Authors: Bruno Jr. Charles A. , Meyers Philip M.
Published: March 2013

Arteriovenous malformations (AVMs) of the brain are rare, complex, vascular lesions that can result in significant morbidity and mortality. Modern treatment of brain AVMs is a multimodality endeavor, requiring a multidisciplinary team with expertise in cerebrovascular neurosurgery, endovascular intervention, and radiation therapy in order to provide all therapeutic options and determine the most appropriate treatment regimen depending on patient characteristics and AVM morphology. Current therapeutic options include microsurgical resection, radiosurgery (focused radiation), and endovascular embolization. Endovascular embolization is primarily used as a preoperative adjuvant before microsurgery or radiosurgery. Palliative embolization has been used successfully to reduce the risk of hemorrhage, alleviate clinical symptoms, and preserve or improve neurological function in inoperable or nonradiosurgical AVMs. Less frequently, embolization is used as ‘primary therapy' particularly for smaller, surgically difficult lesions. Current embolic agents used to treat brain AVMs include both solid and liquid agents. Liquid agents including N-butyl cyanoacrylate and Onyx are the most commonly used agents. As newer embolic agents become available and as microcatheter technology improves, the role of endovascular treatment for brain AVMs will likely expand.
Radiologisch-interventionelle Drainage bei abdomineller Sepsis
Authors: Wiggermann Antonia , Hunold Peter
Published: March 2013

Hintergrund: Durch sekundäre Infektion pankreatischer Nekrosen und Pseudozysten, putride enterische Infektionen und infolge abdominalchirurgischer Eingriffe kann es zur Ausbildung intraabdomineller Abszesse kommen. Diese stellen Foci septischer Dissemination dar. Die anatomische Lage sowie Ausbreitung lässt sich mittels Computertomographie (CT) exakt bestimmen. Einfache Abszesse sind eindeutig abgrenzbar und treten singulär auf. Komplexe Abszessformationen sind häufig multifokal lokalisiert. Bei Abszessformationen >50 mm ist die Indikation zur radiologisch-interventionellen oder chirurgischen Sanierung zu stellen. Methode: In Abhängigkeit von der topographischen Lage des Abszesses erfolgt der Zugang von ventral, perineal, vaginal oder transgluteal. Abszesspunktion und Drainageanlage werden in Direktpunktions-, Tandem-Trokar- oder Seldinger-Technik vorgenommen. Die Punktion wird unter bildgebender Kontrolle mit Fluoroskopie oder Sukzessivsequenzen durchgeführt. Ergebnisse: Die CT-gesteuerte Anlage einer perkutanen Abszessdrainage (PAD) ist im Fall unkomplizierter und gut zugänglicher intraabdomineller Abszesse die Therapie der Wahl. Eine mögliche Verletzung wichtiger Strukturen auf dem Punktionsweg, wie z.B. von Darm, Milz oder großen Gefäßen, stellt jedoch eine Kontraindikation der PAD dar. Schlussfolgerung: Die PAD ist ein sicheres radiologisch-interventionelles Verfahren. Bei geringerer Krankenhausverweildauer und punktionsbedingter Morbidität ist ihr therapeutischer Erfolg mit jenem der chirurgischen Fokussanierung gleichzusetzen.
Rectal Villous Adenoma with McKittrick-Wheelock Syndrome: Report of a Rare Case
Authors: Chen Yu-Hung , Kang Jung-Cheng , Lai Huang-Jen
Published: March 2013

Background: McKittrick-Wheelock syndrome mostly results from colorectal villous adenoma and is characterized by dehydration, hyponatremia, hypokalemia, and prerenal azotemia. Case Report: We report the case of an 84-year-old patient with rectal villous adenoma, presenting with chronic mucous diarrhea for 2 years and subsequent prerenal azotemia. After fluid and electrolyte replenishment, the patient underwent proctectomy and recovered completely. Conclusion: According to a review of the literature, we suggest that surgical resection can achieve a complete recovery.
Therapieziele und Therapieoptionen einer verhaltenstherapeutisch orientierten Ergotherapie
Authors: Linden Michael , Gehrke Guido
Published: March 2013

Hintergrund: Ziel der Ergotherapie ist es, dem Patienten durch den Einsatz von Aktivitäten eine Handlungsfähigkeit im Alltag, gesteigerte Lebensqualität und gesellschaftliche Partizipation zu ermöglichen. Behandlungsziele bei Patienten mit psychischen Störungen umfassen im Einzelnen einen Aktivitätsaufbau und die Förderung des Durchhaltevermögens, der Konzentrationsfähigkeit, der Belastungstoleranz und Ausdauer, der Frustrationstoleranz, der Fähigkeit zu sorgfältigem Arbeiten, zur Arbeitsplanung und Zeiteinteilung, der Kontaktfähigkeit, der Fähigkeit zur Distanzierung von Belastungen sowie der Selbsteinschätzung. Methode: 418 unselektierte Patienten einer Rehabilitationsklinik für psychische und psychosomatische Erkrankungen wurden nach ihren Behandlungszielen in der Ergotherapie befragt. Die darauf ausgerichteten Behandlungsangebote werden beschrieben. Ergebnisse: Patienten erwarten von der Ergotherapie am häufigsten eine bessere Fähigkeit zur Distanzierung von Belastungen (62%), gefolgt von dem Wunsch, ihre Frustrationstoleranz und Gelassenheit zu erhöhen (51%), ihre Konzen tration zu verbessern (50%) sowie das eigene Aktivitätsniveau (40,2%) und Durchhaltevermögen (32,8%) zu steigern und die Selbsteinschätzung (31,8%) zu verbessern. Die niedrigsten Werte fanden sich bezüglich Zeiteinteilung (25,8%), Kontakt fähigkeit (22,7%) sowie Sorgfalt und Arbeitsqualität (12,9%). Die Ergotherapie verfügt zur Erreichung der genannten Therapieziele über eine Reihe von Interventionsmöglichkeiten im Rahmen von Ergotherapiegruppen, Freizeitkompetenzgruppen, Genusstherapiegruppen, Gruppen zur Selbstdarstellung und Selbstpflege, eines Konzentrationstrainings und von Einzelsitzungen. Schlussfolgerungen: Ergotherapie ist der «Salutotherapie» zuzuordnen im Sinne des Wiederaufbaus eines «gesunden Lebens». Bei psychischen Erkrankungen kann sie hinsichtlich der Behandlungsziele wie auch der Interventionsmethoden als psychotherapeutische Methode verstanden werden und stellt mit ihrem handwerklichen Ansatz eine wichtige Ergänzung zu den rein verbalen Psychotherapieformen dar. Schließlich sind die Beobachtungen im Rahmen der Ergotherapie auch eine wichtige Basis bei der Begutachtung der Arbeits- und Leistungsfähigkeit der Patienten.
Characterization of the Reproductive Effects of the Vgf-Derived Peptide TLQP-21 in Female Rats: In vivo and in vitro Studies
Authors: Aguilar Enrique , Pineda Rafael , Gaytán Francisco , Sánchez-Garrido Miguel A. , Romero Magdalena , Romero-Ruiz Antonio , Ruiz-Pino Francisco , Tena-Sempere Manuel , Pinilla Leonor
Published: March 2013

Background: VGF (non-acronymic), a protein expressed in the hypothalamus and pituitary, is involved in the control of metabolism and body weight homeostasis. Different active peptide fragments are generated from VGF, including TLQP-21. Previous studies of our group reported that this molecule participates also in the regulation of reproductive function in male rats, with predominant stimulatory effects. Methods: We report herein a series of studies on the reproductive effects of TLQP-21 in female rats, as evaluated by a combination of in vivo and in vitro analyses. Results: TLQP-21 modestly increased serum LH levels after systemic administration and directly stimulated pituitary LH and FSH secretion in prepubertal female rats, while acute central injection of TLQP-21 was unable to modify LH secretion at this age. Repeated central administration of TLQP-21 during the pubertal transition (between PND-28 and -35) to female rats fed ad libitum advanced the timing of vaginal opening and increased the percentage of animals with signs of ovulation. Moreover, an analogous treatment slightly enhanced ovarian maturation in pubertal female rats subjected to chronic undernutrition, but was unable to rescue the delay of vaginal opening induced by food deprivation. In addition, TLQP-21 oppositely modified LH secretion in adult female rats depending on the stage of the ovarian cycle: it stimulated LH secretion when injected in the morning of diestrus and decreased the magnitude of the preovulatory LH (but not FSH) surge when injected in the afternoon of proestrus. Conclusions: Our data are the first to document the potential involvement of TLQP-21 in the control of reproductive function in female rats.
Quantification in 68Ga-DOTA(0)-Phe(1)-Tyr(3)-Octreotide Positron Emission Tomography/Computed Tomography: Can We Be Impartial about Partial Volume Effects?
Authors: Ruf Juri , Schiefer Jan , Kropf Siegfried , Furth Christian , Ulrich Gerhard , Kosiek Ortrud , Denecke Timm , Pavel Marianne , Pascher Andreas , Wiedenmann Bertram , Amthauer Holger
Published: March 2013

Aim: In combined positron emission tomography/computed tomography (PET/CT) of neuroendocrine neoplasms using 68Ga-DOTA(0)-Phe(1)-Tyr(3)-octreotide (68Ga-DOTATOC), partial volume effects (PVEs) may occur in smaller lesions. This study determined the lesional cutoff size for the occurrence of PVEs in a clinical setting. Methods: Retrospective assessment of 51 PET/CT examinations (16-slice PET/CT device) for malignant PET foci was carried out. In all foci, the maximal standardized uptake value (SUVmax) and maximal lesion diameter on axial CT was documented. Determined SUVmax and lesional sizes were correlated via LOESS regression. In the resulting curve, the cutoff point for SUVmax size dependency was determined visually and mathematically using 2 approximating straight lines. Results: In 45 patients, 313 of 413 PET foci found were malignant, measurable on CT and had a roughly spherical geometry (SUVmax: 2.5-103.3, mean ± SD 20.5 ± 15.18; CT diameter: 5-103 mm, mean ± SD 21.8 ± 13.1 mm). The cutoff lesional size for the occurrence of PVEs was 20.4 mm by the mathematical approach and 25 mm by visual assessment. Conclusion: In 68Ga-DOTATOC imaging, the clinical lesional size threshold is far larger than expected from systemic resolution only. Thus, tracer uptake quantification is only acceptable in sufficiently large lesions.
Coronary Wave Energy
Authors: De Silva Kalpa , Foster Paul , Guilcher Antoine , Bandara Asela , Jogiya Roy , Lockie Tim , Chowiencyzk Phil , Nagel Eike , Marber Michael , Redwood Simon , Plein Sven , Perera Divaka
Published: March 2013

Background—

Revascularization after acute coronary syndromes provides prognostic benefit, provided that the subtended myocardium is viable. The microcirculation and contractility of the subtended myocardium affect propagation of coronary flow, which can be characterized by wave intensity analysis. The study objective was to determine in acute coronary syndromes whether early wave intensity analysis-derived microcirculatory (backward) expansion wave energy predicts late viability, defined by functional recovery.

Methods and Results—

Thirty-one patients (58±11 years) were enrolled after non-ST elevation myocardial infarction. Regional left ventricular function and late-gadolinium enhancement were assessed by cardiac magnetic resonance imaging, before and 3 months after revascularization. The backward-traveling (microcirculatory) expansion wave was derived from wave intensity analysis of phasic coronary pressure and velocity in the infarct-related artery, whereas mean values were used to calculate hyperemic microvascular resistance. Twelve-hour troponin T, left ventricular ejection fraction, and percentage late-gadolinium enhancement mass were 1.35±1.21 µg/L, 56±11%, and 8.4±6.0%, respectively. The infarct-related artery backward-traveling (microcirculatory) expansion wave was inversely correlated with late-gadolinium enhancement infarct mass (
r
=–0.81;
P
<0.0001) and strongly predicted regional left ventricular recovery (
r
=0.68;
P
=0.001). By receiver operating characteristic analysis, a backward-traveling (microcirculatory) expansion wave threshold of 2.8 W m
–2
s
–2
×10
5
predicted functional recovery with sensitivity and specificity of 0.91 and 0.82 (AUC 0.88). Hyperemic microvascular resistance correlated with late-gadolinium enhancement mass (
r
=0.48;
P
=0.03) but not left ventricular recovery (
r
=–0.34;
P
=0.07).

Conclusions—

The microcirculation-derived backward expansion wave is a new index that correlates with the magnitude and location of infarction, which may allow for the prediction of functional myocardial recovery. Coronary wave intensity analysis may facilitate myocardial viability assessment during cardiac catheterization.
Calvatia guzmanii sp. nov. (Agaricaceae, Basidiomycota) from Paraná State, Brazil
Authors: ALVES CAMILA R. , CORTEZ VAGNER G.
Published: March 2013

A new species of Calvatia is described from a semideciduous seasonal forest fragment in the western region of Paraná State, southern Brazil. Calvatia guzmanii is proposed as new based on the combination of dark brown and spiny to velvety exoperidium, prominent subgleba and echinulate-reticulate basidiospores with a short pedicel. A comparison with morphologically similar Calvatia species is giv
Hypotrichous ciliates (Protozoa: Ciliophora) from a temporary pond in Argentina, with redescription of Apoamphisiella hymenophora (Stokes, 1886) Berger, 1999
Authors: KÜPPERS GABRIELA C. , CLAPS MARÍA C.
Published: March 2013

Hypotrichous ciliates collected in the plankton and soil samples from a temporary pond in Buenos Aires province, Argen-tina, were characterized after live observations and protargol impregnation. Apoamphisiella hymenophora (Stokes) Berger is redescribed and the neotype material deposited. Apoamphisiella hymenophora differs from its congeners in having 2 macronuclear nodules, 1 contractile vacuole with anterior and posterior collecting canals, the absence of cortical granules, 2 cirri behind the rightmost frontal cirrus, 1 postoral cirrus, 6 dorsal rows of dikinetids along with scattered dikinetids on the right body margin, and 3–9 caudal cirri arranged in groups at the ends of dorsal rows 1, 2, and 4. Rigidohymena can-dens, R. quadrinucleata, Histriculus histrio, Gastrostyla steinii, and Pseudouroleptus caudatus are new for the Argentine microfauna. Since especially the soil ciliates have been almost unexplored in South America, the results from the present investigation describe and contribute to the knowledge of the diversity of these microorganisms within this geographical region.
Revision of the scolopendrid centipede Digitipes Attems, 1930, from India (Chilopoda: Scolopendromorpha): reconciling molecular and morphological estimates of species diversity
Authors: JOSHI JAHNAVI , EDGECOMBE GREGORY D.
Published: March 2013

Recent work on molecular phylogenetics of Scolopendridae from the Western Ghats, Peninsular India, has suggested the presence of six cryptic species of the otostigmine Digitipes Attems, 1930, together with three species described in previous taxonomic work by Jangi and Dass (1984). Digitipes is the correct generic attribution for a monophyletic group of Indian species, these being united with three species from tropical Africa (including the type) that share a distomedial process on the ultimate leg femur of males that is otherwise unknown in Otostigminae. Second maxillary characters previously used in the diagnosis of Digitipes are dismissed because Indian species do not possess the putatively diagnostic character states. Two new species from the Western Ghats that correspond to groupings identified based on monophyly, sequence diver-gence and coalescent analysis using molecular data are diagnosed based on distinct morphological characters. They are D. jangii and D. periyarensis n. spp. Three species named by Jangi and Dass (Digitipes barnabasi, D. coonoorensis and D. indicus) are revised based on new collections; D. indicus is a junior subjective synonym of Arthrorhabdus jonesii Ver-hoeff, 1938, the combination becoming Digitipes jonesii (Verhoeff, 1938) n. comb. The presence of Arthrorhabdus in In-dia is accordingly refuted. Three putative species delimited by molecular and ecological data remain cryptic from the perspective of diagnostic morphological characters and are presently retained in D. barnabasi, D. jangii and D. jonesii. A molecularly-delimited species that resolved as sister group to a well-supported clade of Indian Digitipes is identified as Otostigmus ruficeps Pocock, 1890, originally described from a single specimen and revised herein. One Indian species originally assigned to Digitipes, D. gravelyi, deviates from confidently-assigned Digitipes with respect to several charac-ters and is reassigned to Otostigmus, as O. gravelyi (Jangi and Dass, 1984) n. comb.
Revision of batfishes (Lophiiformes: Ogcocephalidae) of New Zealand and adjacent waters, with description of two new species of the genus Malthopsis
Authors: HO HSUAN-CHING , ROBERTS CLIVE D. , SHAO KWANG-TSAO
Published: March 2013

Examination and taxonomic review of the batfishes collected from New Zealand and adjacent waters reveals five nominal species: Halieutopsis bathyoreos and Malthopsis mitrigera are recorded from New Zealand for the first time; the synon-ymy of Halieutaea maoria with H. stellata is confirmed, and two new species are described. Malthopsis asparata sp. nov. is unique in having stout principal bucklers with prominent spines. Malthopsis parva sp. nov. differs from congeners in having a naked abdomen, a short rostral spine directed upward, and all principal bucklers blunt.
Relationships between Chinese College Test Takers’ Strategy Use and EFL Reading Test Performance: A Structural Equation Modeling Approach
Authors: Zhang Limei , Zhang Lawrence Jun
Published: March 2013

This article investigates the relationships between test takers’ strategy use and test performance on an EFL reading test. For this study 209 Chinese college students were invited to participate in a reading comprehension test and answer a 30-item strategy use questionnaire. Results showed that two factors underlay test takers’ reading test performance: lexico-grammatical reading ability (LEX-GR) and text comprehension reading ability (TxtCOM). In addition, metacognitive strategy use had a significant and direct effect on cognitive strategy use, implying that the former performed an executive function over the latter. Monitoring strategies were found to have a significant effect on LEX-GR and evaluating strategies significantly affected TxtCOM, suggesting that metacognitive strategy use played an important role on the reading test. Pedagogical implications are also discussed.
The performer’s experience: A case for using qualitative (phenomenological) methodologies in music performance research
Authors: Holmes Patricia , Holmes Christopher
Published: March 2013

The experience of the performer is fundamental to the creation of any music performance, but has as yet received relatively little attention from researchers. Empirical investigation has been undertaken across a range of disciplines (mainly psychology, physiology and psychoacoustics), but hitherto using predominantly quantitative methods. This theoretical article seeks to build on more recent trends towards qualitative research, with the aim of revealing hitherto unexplored aspects of performance, specifically through the subjective world of the performer. To this end, the authors draw on advances in qualitative theory across a range of disciplines, including philosophical reasoning, social science and music education. Cross-discipline theoretical perspectives are offered that centre on both social and cognitive sciences. Theoretical support for a phenomenological approach as a form of philosophical enquiry is discussed, including its potential to illuminate qualitative methods and procedures which have already been shown to be effective in music performance research. Suggestions for further research include the potential to gain insight from a deeper appreciation of the aesthetic embodiment of the artist through more wide-ranging analysis of interview data (for example, relating to the use of metaphor) and also drawing on methodological discussions within other artistic disciplines.
Processing musical form: Behavioural and neurocognitive approaches
Authors: Neuhaus Christiane
Published: March 2013

Simple melodies and short instrumental pieces largely unfold within the temporal limits of working memory. Within short time-spans (typically from 10 to 15 s), listeners can either subsume form parts into higher-order units (chunking process) or perceive them as sequential, and processes like these can happen while listening or in immediate retrospect. This study investigates the listeners’ chunking abilities as well as their assessment of coherence using two eight-measure theme types in AABB and ABAB forms. Double-letter labels (AA and BB) mark pattern similarity, while two-letter labels (AB) indicate pattern contrast. We measured the event-related brain responses (ERPs) while non-musicians listened to musical themes in real-time. Immediately after presentation, each piece of music had to be evaluated as either sequential or non-sequential (hierarchical). The rating results showed that ABAB compared to AABB forms were significantly more often judged as non-sequential (hierarchical). Independent of form type the tendency to chunk form parts seemed stronger when two aspects coincided: when rhythmical contrast between A-parts and B-parts was high, and when melodic contour was upward-downward. In contrast, the event-related potentials were insensitive to mental chunking processes. They merely reflected the brain’s responses to pattern structure. An anterior negative shift (anterior N300) was observed for immediate (AA) as well as for non-immediate repetition (ABA, ABAB) of similar form parts, suggesting pattern matching at phrase onsets on the basis of rhythmical sameness. To our knowledge, this study is the first neurocognitive approach to musical form perception.
Transcranial Direct Current Stimulation (tDCS) of the visual cortex: a proof-of-concept study based on interictal electrophysiological abnormalities in migraine
Authors: Viganò Alessandro , D’Elia Tullia Sasso , Sava Simona Liliana , Auvé Maurie , De Pasqua Victor , Colosimo Alfredo , Di Piero Vittorio , Schoenen Jean , Magis Delphine
Published: March 2013

Background

Preventive pharmacotherapy for migraine is not satisfactory because of the low efficacy/tolerability ratio of many available drugs. Novel and more efficient preventive strategies are therefore warranted. Abnormal excitability of cortical areas appears to play a pivotal role in migraine pathophysiology. Transcranial direct current stimulation (tDCS) is a non-invasive and safe technique that is able to durably modulate the activity of the underlying cerebral cortex, and is being tested in various medical indications. The results of small open studies using tDCS in migraine prophylaxis are conflicting, possibly because the optimal stimulation settings and the brain targets were not well chosen. We have previously shown that the cerebral cortex, especially the visual cortex, is hyperresponsive in migraine patients between attacks and provided evidence from evoked potential studies that this is due to a decreased cortical preactivation level. If one accepts this concept, anodal tDCS over the visual cortex may have therapeutic potentials in migraine prevention, as it is able to increase neuronal firing.

Objective

To study the effects of anodal tDCS on visual cortex activity in healthy volunteers (HV) and episodic migraine without aura patients (MoA), and its potentials for migraine prevention.

Methods

We recorded pattern-reversal visual evoked potentials (VEP) before and after a 15-min session of anodal tDCS over the visual cortex in 11 HV and 13 MoA interictally. Then 10 MoA patients reporting at least 4 attacks/month subsequently participated in a therapeutic study, and received 2 similar sessions of tDCS per week for 8 weeks as migraine preventive therapy.

Results

In HV as well as in MoA, anodal tDCS transiently increased habituation of the VEP N1P1 component. VEP amplitudes were not modified by tDCS. Preventive treatment with anodal tDCS turned out to be beneficial in MoA: migraine attack frequency, migraine days, attack duration and acute medication intake significantly decreased during the treatment period compared to pre-treatment baseline (all p < 0.05), and this benefit persisted on average 4.8 weeks after the end of tDCS.

Conclusions

Anodal tDCS over the visual cortex is thus able to increase habituation to repetitive visual stimuli in healthy volunteers and in episodic migraineurs, who on average lack habituation interictally. Moreover, 2 weekly sessions of anodal tDCS had a significant preventive anti- migraine effect, proofing the concept that the low preactivation level of the visual cortex in migraine patients can be corrected by an activating neurostimulation. The therapeutic results indicate that a larger sham-controlled trial using the same tDCS protocol is worthwhile.
Immunogenic and protective properties of GP5 and M structural proteins of porcine reproductive and respiratory syndrome virus expressed from replicating but nondisseminating adenovectors
Authors: Roques Elodie , Girard Aurélie , St-Louis Marie-Claude , Massie Bernard , Gagnon Carl A , Lessard Martin , Archambault Denis
Published: March 2013

Porcine reproductive and respiratory syndrome virus (PRRSV) is responsible for significant economic losses in the porcine industry. Currently available commercial vaccines do not allow optimal and safe protection. In this study, replicating but nondisseminating adenovectors (rAdV) were used for the first time in pigs for vaccinal purposes. They were expressing the PRRSV matrix M protein in fusion with either the envelope GP5 wild-type protein (M-GP5) which carries the major neutralizing antibody (NAb)-inducing epitope or a mutant form of GP5 (M-GP5m) developed to theoretically increase the NAb immune response. Three groups of fourteen piglets were immunized both intramuscularly and intranasally at 3-week intervals with rAdV expressing the green fluorescent protein (GFP, used as a negative control), M-GP5 or M-GP5m. Two additional groups of pigs were primed with M-GP5m-expressing rAdV followed by a boost with bacterially-expressed recombinant wild-type GP5 or were immunized twice with a PRRSV inactivated commercial vaccine. The results show that the rAdV expressing the fusion proteins of interest induced systemic and mucosal PRRSV GP5-specific antibody response as determined in an ELISA. Moreover the prime with M-GP5m-expressing rAdV and boost with recombinant GP5 showed the highest antibody response against GP5. Following PRRSV experimental challenge, pigs immunized twice with rAdV expressing either M-GP5 or M-GP5m developed partial protection as shown by a decrease in viremia overtime. The lowest viremia levels and/or percentages of macroscopic lung lesions were obtained in pigs immunized twice with either the rAdV expressing M-GP5m or the PRRSV inactivated commercial vaccine.
CD27 expression discriminates porcine T helper cells with functionally distinct properties
Authors: Reutner Katharina , Leitner Judith , Müllebner Andrea , Ladinig Andrea , Essler Sabine E , Duvigneau J Catharina , Ritzmann Mathias , Steinberger Peter , Saalmüller Armin , Gerner Wilhelm
Published: March 2013

Differentiation of porcine T helper cells is still poorly investigated, partly due to a lack of monoclonal antibodies (mAbs) specific for molecules involved in this process. Recently, we identified a mAb specific for porcine CD27 and showed that CD27 is expressed by all naïve CD8α- T helper cells but divides CD8α+ T helper cells into a CD27+ and a CD27- subset. In the present study, detailed phenotypical and functional analyses of these T-helper cell subpopulations were performed. Naïve CD8α-CD27+ T helper cells predominantly resided in various lymph nodes, whereas higher proportions of CD8α+CD27+ and CD8α+CD27- T helper cells were found in blood, spleen and liver. Both CD8α+CD27+ and CD8α+CD27- T helper cells were capable of producing IFN-γ upon in vitro polyclonal stimulation and antigen-specific restimulation. Experiments with sorted CD8α-CD27+, CD8α+CD27+ and CD8α+CD27- T-helper cell subsets following polyclonal stimulation revealed the lowest proliferative response but the highest ability for IFN-γ and TNF-α production in the CD8α+CD27- subset. Therefore, these cells resembled terminally differentiated effector memory cells as described in human. This was supported by analyses of CCR7 and CD62L expression. CD8α+CD27- T helper cells were mostly CCR7- and had considerably reduced CD62L mRNA levels. In contrast, expression of both homing-receptors was increased on CD8α+CD27+ T helper cells, which also had a proliferation rate similar to naïve CD8α-CD27+ T helper cells and showed intermediate levels of cytokine production. Therefore, similar to human, CD8α+CD27+ T helper cells displayed a phenotype and functional properties of central memory cells.