bluuebunny/crossref_metadata_2025 huggingface dataset:
Balance of Inhibitory and Excitatory Synaptic Activity Is Altered in Fast-Spiking Interneurons in Experimental Cortical Dysplasia
Authors: Zhou Fu-Wen , Chen Huan-Xin , Roper Steven N.
Published: August 2009

Cortical dysplasia (CD) is a common cause of intractable epilepsy in children and adults. We have studied rats irradiated in utero as a model of CD to better understand mechanisms that underlie dysplasia-associated epilepsy. Prior studies have shown a reduction in the number of cortical interneurons and in the frequency of inhibitory postsynaptic currents (IPSCs) in pyramidal cells in this model. They have also shown a reduced frequency of spontaneous and miniature excitatory postsynaptic currents (EPSCs) in the surviving cortical interneurons. However, the inhibitory synaptic contacts were not examined in that study. The current experiments were performed to assess inhibitory synaptic activity in fast-spiking (FS) interneurons in irradiated rats and controls and the balance of excitatory and inhibitory synaptic activity in these cells. Whole cell recordings were obtained from layer IV FS cells in controls and comparable FS cells in irradiated rats. The frequency of spontaneous and miniature IPSCs was reduced in dysplastic cortex, but the amplitude of these currents was unchanged. Stimulus-evoked IPSCs showed short-term depression in control and short-term facilitation in dysplastic cortex. Simultaneous recording of spontaneous EPSCs and IPSCs showed a shift in the ratio of excitation-to-inhibition in favor of inhibition in FS cells from dysplastic cortex. The same shift toward inhibition was seen when miniature EPSCs and IPSCs were examined. These results show that FS cells in dysplastic cortex have a relative lack of excitatory drive. This may result in an important class of inhibitory cells that are less able to perform their normal function especially in periods of increased excitatory activity.
Characterizing Learning by Simultaneous Analysis of Continuous and Binary Measures of Performance
Authors: Prerau M. J. , Smith A. C. , Eden Uri T. , Kubota Y. , Yanike M. , Suzuki W. , Graybiel A. M. , Brown E. N.
Published: August 2009

Continuous observations, such as reaction and run times, and binary observations, such as correct/incorrect responses, are recorded routinely in behavioral learning experiments. Although both types of performance measures are often recorded simultaneously, the two have not been used in combination to evaluate learning. We present a state-space model of learning in which the observation process has simultaneously recorded continuous and binary measures of performance. We use these performance measures simultaneously to estimate the model parameters and the unobserved cognitive state process by maximum likelihood using an approximate expectation maximization (EM) algorithm. We introduce the concept of a reaction-time curve and reformulate our previous definitions of the learning curve, the ideal observer curve, the learning trial and between-trial comparisons of performance in terms of the new model. We illustrate the properties of the new model in an analysis of a simulated learning experiment. In the simulated data analysis, simultaneous use of the two measures of performance provided more credible and accurate estimates of the learning than either measure analyzed separately. We also analyze two actual learning experiments in which the performance of rats and of monkeys was tracked across trials by simultaneously recorded reaction and run times and the correct and incorrect responses. In the analysis of the actual experiments, our algorithm gave a straightforward, efficient way to characterize learning by combining continuous and binary measures of performance. This analysis paradigm has implications for characterizing learning and for the more general problem of combining different data types to characterize the properties of a neural system.
Substantia Nigra Output to Prefrontal Cortex Via Thalamus in Monkeys. II. Activity of Thalamic Relay Neurons in Delayed Conditional Go/No-Go Discrimination Task
Authors: Tanibuchi Ikuo , Kitano Hiroyuki , Jinnai Kohnosuke
Published: August 2009

The present report investigated the involvement of primate nigro-thalamo-cortical projections in discrimination of visual signals with behavioral meaning. We tested the extracellular unit activity of mediodorsal (MD) and ventral anterior (VA) thalamic neurons monosynaptically receiving inhibitory input from the substantia nigra pars reticulata (SNr) and projecting to the frontal cortex in Japanese monkeys performing a delayed conditional go/no-go discrimination task. In the task two colored stimuli (S1, S2) intervened by delay period required the monkeys lifting a lever (go) or not (no-go); the same and different colored pairs of S1 and S2 meant go and no-go signals, respectively. Prominent task-relevant responses were sustained activity with color preference to S1 during delay period and S2-related activity with different firing rates between go and no-go trials. In particular, a high proportion of such go/no-go differential S2-related activity was found in thalamic relay neurons, receiving input from the caudolateral SNr and projecting to the prefrontal area (PSv) ventral to the principal sulcus, in the rostrolateral MD. The findings suggest that the caudolateral SNr–rostrolateral MD–PSv pathways may be possible conduits of signals coding the behavioral meaning of the visual stimuli and thus may be responsible for generating similar neuronal activity in the PSv.
Chronic Recanalization of Dissection of the Distal Anterior Cerebral Artery: Case Report and Review of the Literature
Authors: Asano Shuichiro , Hara Tetsuo
Published: August 2009

The natural history of atraumatic idiopathic dissection of the distal anterior cerebral artery is still unclear. We present a 38-year-old man who had dissection of the leftA2segment of this vessel associated with subintimal hematoma and infarction. Because of complete stroke in acute stage, he did not undergo surgery. About three months later, administration of aspirin (100 mg/day) was started. At nine months, magnetic resonance angiography revealed complete recanalization of theA2dissection. To assess the outcome of dissection, we should observe the patient for at least one year.
Global Asymptotic Stability of 3‐Species Mutualism Models with Diffusion and Delay Effects
Authors: Wang Chang-you , Wang Shu , Yan Xiang-ping
Published: August 2009

In this paper, the Lotka‐Volterra 3‐species mutualism models
with diffusion and delay effects is investigated. A simple and easily
verifiable condition is given to ensure the global asymptotic stability of
the unique positive steady‐state solution of the corresponding steady‐state
problem in a bounded domain with Neumann boundary condition. Our
approach to the problem is based on inequality skill and the method of the
upper and lower solutions for a more general reaction—diffusion system.
Finally, some numerical simulations are given to illustrate our results.
Output Feedback Stabilization of Linear Time‐Varying Uncertain Delay Systems
Authors: Hashimoto Tomoaki , Amemiya Takashi
Published: August 2009

This paper investigates the output feedback stabilization problem of linear time‐varying uncertain delay systems with limited measurable state variables. Each uncertain parameter and each delay under consideration may
take arbitrarily large values. In such a situation, the locations of uncertain entries in the system matrices play an important role. It has been shown that if a system has a particular configuration called a triangular configuration,
then the system is stabilizable irrespective of the given bounds of uncertain variations. In the results so far obtained, the stabilization problem has been reduced to finding the proper variable transformation such that
an M‐matrix stability criterion is satisfied. However, it still has not been shown whether the constructed variable transformation enables the system to satisfy the M‐matrix stability condition. The objective of this paper is to
show a method that enables verification of whether the transformed system satisfies the M‐matrix stability condition.
Peroxisome Proliferator‐Activated Receptor Agonists: Do They Increase Cardiovascular Risk?
Authors: Aljada Ahmad , Shah Kshitij Ashwin , Mousa Shaker A.
Published: August 2009

Cardiovascular disease is a major cause of morbidity and mortality among people with type 2 diabetes mellitus. The peroxisome proliferator‐activated receptor (PPAR) agonists have a significant role on glucose and fat metabolism. Thiazolidinediones (TZDs) are predominantly PPARγ
agonists, and their primary benefit appears to be the prevention of diabetic complications by improving glycemic control and lipid profile. Recently, the cardiovascular safety of rosiglitazone was brought to center stage following meta analyses and the interim analysis of the RECORD trial. Current evidence points to rosiglitazone having a greater risk of myocardial ischemic events than placebo, metformin, or sulfonylureas. This review article discusses the mechanism of action of PPAR agonists and correlates it with clinical and laboratory outcomes in the published literature. In addition, this review article attempts to discuss some of the molecular mechanisms regarding the association between TZDs therapy and the nontraditional cardiovascular risks.
Primary Cardiac Angiosarcoma: A Fatal Disease
Authors: Antonuzzo L. , Rotella V. , Mazzoni F. , Doni L. , Bianchini D. , Garbini F. , Maio V. , Di Costanzo F.
Published: August 2009

A 42-year-old man with a cardiac tamponade underwent an urgent pericardiotomy that showed tumoral tissue, covering the surface of the right atrium. The tumor was then partially excised, and the histological examination revealed the presence of a moderately-differentiated angiosarcoma. The patient was then referred to the oncology unit and scheduled for a chemotherapy schedule including Epirubicin (60 mg/m2, on days 1 and 2) plus Ifosfamide (2000 mg/m2, on days 1 to 3) and Uromitexan (2000 mg/m2at hours 0, 4, 8 after IFO). All drugs were administered every three weeks. After two cycles, a restaging work-up revealed a partial remission. The treatment was continued for another two cycles. A new evaluation by cardiac MRI evidenced a local and distant (lung) progression of disease. The patient died after three months. This paper confirms that cardiac angiosarcoma is a fatal disease, and the prognosis is usually 6–11 months from time of diagnosis.
Short Bowel Patients Treated for Two Years with Glucagon-Like Peptide 2: Effects on Intestinal Morphology and Absorption, Renal Function, Bone and Body Composition, and Muscle Function
Authors: Jeppesen P. B. , Lund P. , Gottschalck I. B. , Nielsen H. B. , Holst J. J. , Mortensen J. , Poulsen S. S. , Quistorff B. , Mortensen P. B.
Published: August 2009

Background and aims. In a short-term study, Glucagon-like peptide 2 (GLP-2) has been shown to improve intestinal absorption in short bowel syndrome (SBS) patients. This study describes longitudinal changes in relation to GLP-2 treatment for two years.Methods. GLP-2, 400 micrograms, s.c.,TID, were offered, to eleven SBS patients keeping parenteral support constant. 72-hour nutritional balance studies were performed at baseline, weeks 13, 26, 52 during two years intermitted by an 8-week washout period. In addition, mucosal morphometrics, renal function (by creatinine clearance), body composition and bone mineral density (by DEXA), biochemical markers of bone turnover (by s-CTX and osteocalcin, PTH and vitamin D), and muscle function (NMR, lungfunction, exercise test) were measured.Results. GLP-2 compliance was 93%. Three of eleven patients did not complete the study. In the remaining 8 patients, GLP-2 significantly reduced the fecal wet weight from approximately 3.0 to approximately 2.0 kg/day. This was accompanied by a decline in the oral wet weight intake, maintaining intestinal wet weight absorption and urinary weight constant. Renal function improved. No significant changes were demonstrated in energy intake or absorption, and GLP-2 did not significantly affect mucosal morphology, body composition, bone mineral density or muscle function.Conclusions. GLP-2 treatment reduces fecal weight by approximately 1000 g/d and enables SBS patients to maintain their intestinal fluid and electrolyte absorption at lower oral intakes. This was accompanied by a 28% improvement in creatinine clearance.
Extracorporeal Cardiac Shock Wave Therapy Ameliorates Clinical Symptoms and Improves Regional Myocardial Blood Flow in a Patient with Severe Coronary Artery Disease and Refractory Angina
Authors: Prinz Christian , Lindner Oliver , Bitter Thomas , Hering Detlef , Burchert Wolfgang , Horstkotte Dieter , Faber Lothar
Published: August 2009

Different therapeutic options are being used for chronic coronary artery disease (CAD). We report about a 51-year-old female with CAD and refractory angina pectoris despite maximally tolerated medical therapy and after both percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG). The patient received cardiac shock wave therapy (CSWT) over a period of 6 month. There was no arrhythmia during or after treatment; enzyme levels were normal at all times. PET imaging showed a substantial improvement of myocardial stress perfusion. Since the patient reported that she now was fully capable to deal with her everyday life, further treatment options were postponed. Our case report suggests that ultrasound-guided CSWT is able to improve symptoms and perfusion in ischemic myocardium.
Flux Reflection Model of the Ferroresonant Circuit
Authors: Miličević Kruno , Flegar Ivan , Pelin Denis
Published: August 2009

The paper presents a linear model of ferroresonant circuit with flux reflection. The proposed model—flux reflection model—derives from observations of typical flux waveforms of nonlinear coil during ferroresonant steady states. Simulation results of the flux reflection model are compared with simulation results of the usual nonlinear model as well as with measurements carried out on the
physical model of the ferroresonant circuit. The flux reflection model enables a novel comprehension
of the ferroresonant circuit behavior and simplifies the modeling of the nonlinear coil in the
ferroresonant circuit.
Rigorous Coupled‐Wave Analysis of Surface Plasmon Enhancement from Patterned Immobilization on Nanogratings
Authors: Hoa Xuyen D. , Tabrizian Maryam , Kirk Andrew G.
Published: August 2009

We numerically evaluate the optical response of a Kretschmann surface plasmon resonance (SPR) biosensor featuring metallic nanogratings and patterned immobilization of surface receptors. Parameters are chosen such that the biosensor is operated near the generated bandgap of the surface plasmon dispersion. In this paper, we demonstrate that the sensitivity can be increased by concentrating the surface receptors and adsorbed analytes on regions where the field intensity is the greatest. Specifically, a surface presenting receptors on the grating mesas is shown to be twice as sensitive as that of a uniformly functionalized corrugated surface. The grating geometries are also studied; it is found that higher aspect ratio features show increased SPR response. The analysis differs from existing studies of enhanced SPR as the sensitivity improvement originating from the concentration and mapping of surface receptors to the plasmon field distribution is studied rather than the absorption or scattering enhancement effect of the nanostructures.
Numerical Treatment of Fixed Point Applied to the Nonlinear Fredholm Integral Equation
Authors: Berenguer M. I. , Fernández Muñoz M. V. , Garralda Guillem A. I. , Ruiz Galán M.
Published: August 2009

The authors present a method of numerical approximation of the fixed point of an operator, specifically the integral one associated with a nonlinear Fredholm integral equation, that uses strongly the properties of a classical Schauder basis in the Banach space "Equation missing".
Mobile Messaging Services-Based Personal Electrocardiogram Monitoring System
Authors: Tahat Ashraf A.
Published: August 2009

A mobile monitoring system utilizing Bluetooth and mobile messaging services (MMS/SMSs) with low-cost hardware equipment is proposed. A proof of concept prototype has been developed and implemented to enable transmission of an Electrocardiogram (ECG) signal and body temperature of a patient, which can be expanded to include other vital signs. Communication between a mobile smart-phone and the ECG and temperature acquisition apparatus is implemented using the popular personal area network standard specification Bluetooth. When utilizing MMS for transmission, the mobile phone plots the received ECG signal and displays the temperature using special application software running on the client mobile phone itself, where the plot can be captured and saved as an image before transmission. Alternatively, SMS can be selected as a transmission means, where in this scenario, dedicated application software is required at the receiving device. The experimental setup can be operated for monitoring from anywhere in the globe covered by a cellular network that offers data services.
TJ-41 Induces Apoptosis and Potentiates the Apoptotic Effects of 5-FU in Breast Cancer Cell Lines
Authors: Volate Suresh , Hudson Robert , Wang Desuo , Muga Stephanie , Wargovich Michael
Published: August 2009

Recent studies suggest that TJ-41, a herbal drug, possesses chemotherapeutic effects. Accordingly, this study was undertaken to investigate the anticarcinogenic effects of TJ-41 on human breast cancer cells lines. TJ-41 inhibited the proliferation of human breast cancer cell lines dose dependently. Flow cytometric analysis showed that this decrease in DNA synthesis is to be associated with induction of apoptosis. In both cell lines, apoptosis was abolished by caspase-9 inhibitor Z-LEHD-fmk but was weakly inhibited by caspase-8 inhibitor Z-IETD-fmk, indicating that caspase-9 activation was involved in TJ-41 induced apoptosis. Additionally, TJ-41 stimulated phosphorylation of c-Jun NH2-terminal kinase (JNK) and pretreatment of breast cancer cells with JNK inhibitor SP600125 completely abolished TJ-41 induced apoptosis. Our data also demonstrate that combined treatment of TJ-41 and 5-FU significantly potentiates the apoptotic effects of 5-FU in both breast cancer cell lines. Taken together, these data suggest that TJ-41 might provide a novel chemotherapeutic treatment for breast cancer.
Effects of Aquajogging in Obese Adults: A Pilot Study
Authors: Wouters Eveline J. M. , Van Nunen Annemieke M. A. , Geenen Rinie , Kolotkin Ronette L. , Vingerhoets Ad J. J. M.
Published: August 2009

Aim and Method. To examine in obese people the potential effectiveness of a six-week, two times weekly aquajogging program on body composition, fitness, health-related quality of life, and exercise beliefs. Fifteen otherwise healthy obese persons participated in a pilot study.Results. Total fat mass and waist circumference decreased 1.4 kg (P=.03) and 3.1 cm (P=.005), respectively. The distance in the Six-Minute Walk Test increased 41 meters (P=.001). Three scales of the Impact of Weight on Quality of Life-Lite questionnaire improved: physical function (P=.008), self-esteem (P=.004), and public distress (P=.04). Increased perceived exercise benefits (P=.02) and decreased embarrassment (P=.03) were observed.Conclusions. Aquajogging was associated with reduced body fat and waist circumference and improved aerobic fitness and quality of life. These findings suggest the usefulness of conducting a randomized controlled trial with long-term outcome assessments.
Fyn and Src Are Effectors of Oncogenic Epidermal Growth Factor Receptor Signaling in Glioblastoma Patients
Authors: Lu Kan V. , Zhu Shaojun , Cvrljevic Anna , Huang Tiffany T. , Sarkaria Shawn , Ahkavan David , Dang Julie , Dinca Eduard B. , Plaisier Seema B. , Oderberg Isaac , Lee Yohan , Chen Zugen , Caldwell Jeremy S. , Xie Yongmin , Loo Joseph A. , Seligson David , Chakravari Arnab , Lee Francis Y. , Weinmann Roberto , Cloughesy Timothy F. , Nelson Stanley F. , Bergers Gabriele , Graeber Thomas , Furnari Frank B. , James C. David , Cavenee Webster K. , Johns Terrance G. , Mischel Paul S.
Published: August 2009

Activating epidermal growth factor receptor (EGFR) mutations are common in many cancers including glioblastoma. However, clinical responses to EGFR inhibitors are infrequent and short-lived. We show that the Src family kinases (SFK) Fyn and Src are effectors of oncogenic EGFR signaling, enhancing invasion and tumor cell survival in vivo. Expression of a constitutively active EGFR mutant, EGFRvIII, resulted in activating phosphorylation and physical association with Src and Fyn, promoting tumor growth and motility. Gene silencing of Fyn and Src limited EGFR- and EGFRvIII-dependent tumor cell motility. The SFK inhibitor dasatinib inhibited invasion, promoted tumor regression, and induced apoptosis in vivo, significantly prolonging survival of an orthotopic glioblastoma model expressing endogenous EGFRvIII. Dasatinib enhanced the efficacy of an anti-EGFR monoclonal antibody (mAb 806) in vivo, further limiting tumor growth and extending survival. Examination of a large cohort of clinical samples showed frequent coactivation of EGFR and SFKs in glioblastoma patients. These results establish a mechanism linking EGFR signaling with Fyn and Src activation to promote tumor progression and invasion in vivo and provide rationale for combined anti-EGFR and anti-SFK targeted therapies. [Cancer Res 2009;69(17):6889–98]
A Critique of the UK NICE Guidance for the Detection and Management of Individuals with Chronic Kidney Disease
Authors: Khwaja Arif , Throssell David
Published: August 2009

The increasing global prevalence of chronic kidney disease (CKD) and end-stage renal disease (ESRD) has significant public health and economic implications. The recently published UK National Institute for Health and Clinical Excellence (NICE) clinical guidelines for the early identification and management of CKD provide a framework of disease management for both primary and secondary care with the stated aim of reducing the progression of CKD and the associated risk of cardiovascular death. Identification of at-risk individuals with proteinuria and inhibition of the renin-angiotensin system are the cornerstones of this strategy. However, the vast majority of patients with CKD will not develop ESRD and it is far from clear whether the NICE recommendations will reduce either ESRD or cardiovascular death associated with CKD.
Skin Efficacy and Biophysical Assessment of Glycerol-Containing Hydrocolloid Patches
Authors: De Paepe K. , Wibaux A. , Ward C. , Rogiers V.
Published: August 2009

Hydrocolloid patches are developed with 10, 20 and 30% (w/w) glycerol as the main active ingredient. By making use of two experimental forearm models, skin efficacy and its dependency on the glycerol concentration applied were compared with a blank reference patch, a commercialized protective patch and a cosmetic barrier cream. Skin hydration and transepidermal water loss measurements were combined with skin erythema assessments. After a single application to healthy skin, a clear concentration-dependent effect of glycerol-containing patches was observed with – for the highest glycerol content – a 31% increase in skin hydration and an improvement in skin barrier properties of 15%. This glycerol-containing patch also accelerated barrier recovery of mechanically irritated skin after stripping with cyanoacrylate tape. After 7 days of repetitive application, a significantly hydrating effect of the 30% glycerol-containing patch was observed, which was of the same order of magnitude as observed for the cosmetic barrier cream, the latter being applied twice daily. The effects seen were maximal after 3 days of patch application.
Immunohistochemical Examinations of Sex Hormone Receptors in Benign Vocal Fold Lesions
Authors: Cohen Eleonore , Kolbus Andrea , van Trotsenburg Michael , Rudas Margarethe , Horvat Reinhard , Schneider Berit
Published: August 2009

Background: Acquired benign vocal fold lesions are among the most common causes of voice problems. Since the local impact of estrogen and progesterone receptors in laryngeal tissue is discussed controversially, the presence of sex hormone receptors in benign vocal fold alterations needs to be clarified. Goal of the Study: To investigate the expression of estrogen-α receptors (ER-α), estrogen-β receptors (ER-β), progesterone receptors (PR) and androgen receptors (AR) in acquired benign vocal fold alterations. Methods: Laryngeal epithelial specimens of 14 patients (13 female, 1 male) taken intraoperatively were investigated using immunohistochemistry in order to objectify ER-α, ER-β, PR and AR. Macroscopically and histopathologically diagnosed edemas of Reinke’s space (n = 10), vocal fold polyps (n = 3) and vocal fold nodules (n = 1) were enrolled in this study. Results: No specific nuclear immunohistochemical staining could be seen in the biopsies taken. Only unspecific staining patterns could be observed. Conclusion: Sex hormone receptors could not be detected in the specimens tested, thus, any direct influence of sex hormones on the development of benign vocal fold lesions is rather unlikely. The results of this study confirm the impact of vocal fold stress and biomechanical abnormalities on their development due to voice overstraining and abuse.
The Effectiveness of Collaborative Medicine Reviews in Delaying Time to Next Hospitalization for Patients With Heart Failure in the Practice Setting
Authors: Roughead Elizabeth E. , Barratt John D. , Ramsay Emmae , Pratt Nicole , Ryan Philip , Peck Robert , Killer Graeme , Gilbert Andrew L.
Published: August 2009

Background—

Randomized controlled trials have demonstrated that collaborative medication reviews can improve outcomes for patients with heart failure. We aimed to determine whether these results translated into Australian practice, where collaborative reviews are nationally funded.

Methods and Results—

This retrospective cohort study using administrative claims data included veterans 65 years and older receiving bisoprolol, carvedilol, or metoprolol succinate for which prescribing physicians indicated treatment was for heart failure. We compared those exposed to a general practitioner–pharmacist collaborative home medication review with those who did not receive the service. The service includes physician referral, a home visit by an accredited pharmacist to identify medication-related problems, and a pharmacist report with follow-up undertaken by the physician. Kaplan-Meier analyses and Cox proportional hazards models were used to compare time until next hospitalization for heart failure between the exposed and unexposed groups. There were 273 veterans exposed to a home medicines review and 5444 unexposed patients. Average age in both groups was 81.6 years (no significant difference). The median number of comorbidities was 8 in the exposed group and 7 in the unexposed (
P
<0.0001). Unadjusted results showed a 37% reduction in rate of hospitalization for heart failure at any time (hazard ratio, 0.63; 95% CI, 0.44 to 0.89). Adjusted results showed a 45% reduction (hazard ratio, 0.55; 95% CI, 0.39 to 0.77) among those who had received a home medicines review compared with the unexposed patients.

Conclusion—

Medicines review in the practice setting is effective in delaying time to next hospitalization for heart failure in those treated with heart failure medicines.
Spatial Selective Attention Affects Early Extrastriate But Not Striate Components of the Visual Evoked Potential
Authors: Clark Vincent P. , Hillyard Steven A.
Published: August 2009

The effects of spatial selective attention on sensory processing in visual cortical areas were investigated by means of visual evoked potential (VEP) recordings and source localization techniques. Patterned stimuli were rapidly presented in random order to the left and right visual fields while subjects maintained central fixation and attended to one visual field at a time. Attended stimuli evoked enhanced P1 (100–130 msec) and N1 (120–200 msec) components of the VEP, whereas no effects of attention were observed on the C1 (50–100 msec) or P2 (200–240 msec) components. Spatiotemporal dipole modeling of the early VEP sources was carried out in relation to MRI-defined cortical anatomy. The dipolar generator of the C1 component was found to lie in calcarine cortex, the human homologue of area V1, whereas the attention-sensitive P1 generator was localized to ventral-lateral occipital cortex, within extrastriate area 19. These results support the hypothesis that spatial attention does not affect the initial activity evoked in area V1 but rather produces an enhancement within extrastriate visual areas of sensory signals arising from stimuli at attended locations.
Can We Lose Memory for Music? A Case of Music Agnosia in a Nonmusician
Authors: Peretz Isabelle
Published: August 2009

A follow-up study of a patient, C.N., with a severe auditory agnosia limited to music is reported. After bilateral temporal lobe damage, C.N., whose cognitive and speech functions are otherwise normal, is totally unable to identify or to experience a sense of familiarity with musical excerpts that were once highly familiar to her. However, she can recognize the lyrics that usually accompany the songs. She can also identify familiar sounds, such as animal cries. Thus, her agnosia appears highly specific to music. The functional nature of her deficit has been investigated through various perceptual tasks. She was initially severely impaired in processing pitch sequential structure but has always enjoyed normal processing of temporal structure. This selective disturbance for sequential pitch information can hardly account for her tune agnosia since processing of pitch variations has dramatically improved over the years. This recovery was not accompanied by any signs of improvement in music recognition, which remains extremely poor. Moreover, the fact that she has never been able to hum tunes from memory argues for a basic memory disturbance. Thus, she was tested here with a series of tests aiming at assessing her memory for familiar and unfamiliar music. The results show that C.N. has now recovered most perceptual skills and that despite a transient ability to exhibit knowledge of familiar music under restricted circumstances, she is markedly impaired at naming a tune and at judging its familiarity, as well as at memorizing familiar as well as novel music. This deficit was found to be not only modality-specific but music-specific as well. The findings suggest the existence of a perceptual memory that is specialized for music and that can be selectively damaged so as to prevent most forms of recognition ability.
Enhancement of Perceived Visual Intensity by Auditory Stimuli: A Psychophysical Analysis
Authors: Stein Barry E. , London Nancy , Wilkinson Lee K. , Price Donald D.
Published: August 2009

Judgments of the intensity of a stimulus are dependent on the level of central nervous system activity it generates. Generally, it is assumed that such judgments are based on activity along modality-specific pathways. Thus, visual intensity judgments would be based on unimodal visual activity. However, many neurons do not fit neatly within modality-specific categories, but can be influenced by more than one sensory modality. Often the “multisensory” effect is quite pronounced. If these multisensory neurons participate in such fundamental functions as perceived intensity, the presence of a nonvisual (i.e., auditory) cue may have a significant effect on the perceived intensity of a visual cue. The results of the present study were consistent with such a hypothesis. A brief, broad-band auditory stimulus was found to significantly enhance the perceived intensity of an LED. The effect was most pronounced at the lowest visual intensities, and was evident regardless of the location of the auditory cue. However, it was present only at the location of visual fixation. Yet, despite the significant influence of the auditory cue, and its differential effect at different visual intensities, a power function that maintains the proportionality among perceived visual intensities was retained.
A Neural Mechanism for Involuntary Attention Shifts to Changes in Auditory Stimulation
Authors: Schröger Erich
Published: August 2009

Involuntary switching to task-irrelevant sound change was studied by measuring event-related brain potentials (ERPs) and behavioral performance in a dichotic listening paradigm. Pairs of tones (S1 and S2) were presented and subjects were instructed to ignore S1 (delivered to the left ear) and to make a go/no-go response to the subsequent S2 (delivered to the right ear). On most trials, the task-irrelevant S1 was of standard frequency, but occasionally it deviated from the standard frequency either by a small or large amount. It was predicted that deviant stimuli were automatically detected and that they could involuntarily capture attention. If they lead to attention switching, less capacity should be available for the processing of target tones resulting in impaired processing of S2. As in many previous studies, deviant tones elicited the mismatch negativity (MMN), which is a component of the ERP indicating automatic change detection. Furthermore, targets preceded by a deviant tone elicited a smaller N1 wave and were detected less effectively than targets preceded by a standard tone. This impaired processing of targets following task-irrelevant changes occurred only with short S1–S2 intervals (Experiment I) but not with long ones (Experiment II). The results support a model claiming that the auditory system possesses a change detection system that monitors the acoustic input and may produce an attentional “interrupt” signal when a deviant occurs. The involuntary attentional capture caused by this signal leads to impoverished processing of closely succeeding stimuli.
Object-Centered Attentional Biases in the Intact Brain
Authors: Reuter-Lorenz Patricia A. , Drain Maxwell , Hardy-Morais Corinne
Published: August 2009

By simulating neglect-like effects in neurologically intact observers, we evaluated whether normal attentional allocation can be object centered. In a series of three experiments, observers detected a small gap on the left or right side of a configuration presented in either the left of right visual field. The figures were positioned so that on different trials, the left and right sides would fall in the same retinotopic, hemispatial, and environmental location. Thus, only the location with respect to an object-centered frame varied. We found opposite patterns of bias within each visual field: For figures in the left visual field, left gaps were detected better than right gaps, whereas in the right visual field the opposite pattern was evident. Control conditions indicate that these biases are not due to masking from eccentric contours and depend on the left and right segments being united into a single form. These results indicate that opposing orientational biases of the left and right hemispheres can operate within an object-centered frame in the normal brain. This evidence converges with patient studies and single-unit electrophysiology to reveal the importance of a relatively late, abstract locus for visual selection.
MRI-Based Topographic Parcellation of Human Neocortex: An Anatomically Specified Method with Estimate of Reliability
Authors: Caviness Verne S. , Meyer James , Makris Nikos , Kennedy David N.
Published: August 2009

We describe a system of parcellation of the human neocortex, based upon magnetic resonance images, that conserves the topographic uniqueness of the individual brain. Subdivision of the neocortex, according to this system, is based entirely upon the configuration of a specified set of cerebral landmarks, principally neocortical fissures. These are present but unique in the details of their configurations in each individual brain. We introduce here a computer-assisted algorithm that ensures that a skilled investigator can execute the parcellation routine in a manageable period of time. Secondly, we outline a comprehensive set of conventions that specify how the boundaries of parcellation units are defined by anatomic landmarks. The average interobserver agreement in voxel assignment to parcellation units within the overall neocortex was 80.2%.
A Specific Role for the Right Parahippocampal Gyrus in the Retrieval of Object-Location: A Positron Emission Tomography Study
Authors: Owen Adrian M. , Milner Brenda , Petrides Michael , Evans Alan C.
Published: August 2009

A plethora of studies, across many species, have now demonstrated that the hippocampal region plays a critical role in memory for spatial location. In spite of this compelling evidence, a number of important neuropsychological and neuroanatomical issues remain unresolved. In the present study, the functional anatomy of object-location memory was investigated using positron emission tomography (PET) with magnetic resonance imaging (MRI). Regional cerebral blood flow (rCBF) was measured while normal volunteers encoded, and then retrieved, the locations of eight familiar objects presented on a computer screen. In two analogous conditions, designed to fractionate object-location memory into its component processes, the subjects were simply required to encode, and then to retrieve, eight distinct locations represented by identical white boxes on the screen. An increase in rCBF was observed in the region of the right parahippocampal gyrus corresponding to entorhinal cortex when the Retrieving Location condition was subtracted from the Retrieving Object-Location condition. In contrast, when the Encoding Location condition was subtracted from the Encoding Object-Location condition, no significant rCBF changes were observed in the hippocampal region although significant activation was observed, bilaterally, in the anterior fusiform gyrus. In addition, the two encoding conditions activated left-hemisphere regions preferentially, whereas the two retrieval conditions activated right-hemisphere regions.

Together, these findings suggest that the human right hippocampal region is critically involved in retrieving information that links object to place. The secondary finding that encoding and retrieval appear to be lateralized to the left and right hemispheres respectively, is discussed with reference to current models of episodic memory, and alternative hypotheses are considered.
The Role of Neuronal Synchronization in Response Selection: A Biologically Plausible Theory of Structured Representations in the Visual Cortex
Authors: Roelfsema Pieter R. , Engel Andreas K. , König Peter , Singer Wolf
Published: August 2009

Recent experimental results in the visual cortex of cats and monkeys have suggested an important role for synchronization of neuronal activity on a millisecond time scale. Synchronization has been found to occur selectively between neuronal responses to related image components. This suggests that not only the firing rates of neurons but also the relative timing of their action potentials is used as a coding dimension. Thus, a powerful relational code would be available, in addition to the rate code, for the representation of perceptual objects. This could alleviate difficulties in the simultaneous representation of multiple objects. In this article we present a set of theoretical arguments and predictions concerning the mechanisms that could group neurons responding to related image components into coherently active aggregates. Synchrony is likely to be mediated by synchronizing connections; we introduce the concept of an interaction skeleton to refer to the subset of synchronizing connections that are rendered effective by a particular stimulus configuration. If the image is segmented into objects, these objects can typically be segmented further into their constituent parts. The synchronization behavior of neurons that represent the various image components may accurately reflect this hierarchical clustering. We propose that the range of synchronizing interactions is a dynamic parameter of the cortical network, so that the grain of the resultant grouping process may be adapted to the actual behavioral requirements.

It can be argued that different aspects of purposeful behavior rely on separable processes by which sensory input is transformed into adjustments of motor activity. Indeed, neurophysiological evidence has suggested separate processing streams originating in the primary visual cortex for object identification and sensorimotor coordination. However, such a separation calls for a mechanism that avoids interference effects in the presence of multiple objects, or when multiple motor programs are simultaneously prepared. In this article we suggest that synchronization between responses of neurons in both the visual cortex and in areas that are involved in response selection and execution might allow for a selective routing of sensory information to the appropriate motor program.
On Three Extant Sources of the Qur'an Transcribed in Hebrew
Authors: Paudice Aleida
Published: August 2009

This paper focuses on three extant sources of transcriptions of the Qur'an into Hebrew characters: manuscript Arab N. 5 found in the library of the Morgenländische Gesellschaft, the fragments of the Qur'an from the Cairo Genizah kept in the Cambridge University Library, and manuscript Vat. Ebr. 357 from the Vatican Library in Rome. The article focuses in particular on the Halle manuscript, a transcription of which is given in the appendix. The transcriptions of the Qur'an examined here show how each one was produced in a different milieu and served specific purposes. The fragments from the Cairo Genizah and the Halle manuscript served similar polemical purposes and were written in countries under Muslim rule, where knowledge of Arabic was important for the relations with the authorities and, certainly in Egypt, was a part of everyday life. By contrast, the Vatican manuscript places itself in a very different context, that of the cultural milieu of Jewish and Christian philosophers and scholars in the period of the Italian Renaissance.
Polish-Jewish Relations in the Kingdom of Poland During the First World War
Authors: Zieliński Konrad
Published: August 2009

The First World War, and particularly the occupation by the Central States, had a great impact upon the relations of the Jews with the Poles. During this period, Polish-Jewish relations deteriorated. The growing economic problems as well as the rise of the nationalistic mood accompanying the approaching independence supported this tendency. At the same time, the new social and political situation, the relative liberalism of the occupying forces, the free elections, the activities of self-government, and the emergence of the Polish autonomous institutions created new possibilities for Polish-Jewish cooperation. Yet more often they actually multiplied the areas of conflict. In the autumn of 1918 there had been pogroms in the Kingdom of Poland: Polish-Jewish relations apparently worsened in big cities as well as in the small towns and the countryside, which earlier had been relatively free from anti-Semitism.
Evaluation of AATSR and TMI Satellite SST Data
Authors: Reynolds Richard W. , Gentemann Chelle L. , Corlett Gary K.
Published: August 2009

The purpose of this paper is to investigate two satellite instruments for SST: the infrared (IR) Advanced Along Track Scanning Radiometer (AATSR) and the microwave (MW) Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI). Because of its dual view, AATSR has a potential for lower biases than other IR products such as the Advanced Very High Resolution Radiometer (AVHRR), while the tropical TMI record was available for a longer period of time than the global MW instrument, the Advanced Microwave Scanning Radiometer (AMSR).

The results show that the AATSR IR retrievals are good quality with biases lower than or as low as other satellite retrievals between 50°S and 50°N. Furthermore, the dual-view algorithm reduces the influence of aerosol contamination. However, the AATSR coverage is roughly half that of AVHRR. North of 50°N there appear to be biases and high variability in summer daytime retrievals, with smaller but consistent biases observed below 50°S. TMI data can significantly improve coverage offshore in regions where IR retrievals are reduced by cloud cover. However, TMI data have small-scale biases from land contamination that should be removed by modifying the land–sea mask to remove more coastal regions.
The Influence of Upper-Tropospheric Potential Vorticity on Convective Morphology
Authors: Schumann Melissa R. , Roebber Paul J.
Published: August 2009

Extensive research has illuminated the roles that buoyancy and vertical wind shear have in determining convective mode. The goal of this study is to examine synoptic forcing, as measured by the form of the waves on the dynamic tropopause and the strength of the resultant temperature advection, together with the environmental variables that are currently used to differentiate storm type. Logistic regression is used to make this discrimination and provides the preliminary results. First, multicellular lines and isolated rotating cells are associated with weaker synoptic forcing. Second, where an upper-level feature is present, multicellular convection (lines and clusters combined) is favored relative to isolated storms when there is stronger synoptic forcing, the shape of the upper-level potential vorticity (PV) feature is elongated, and there is a more southerly component in the deep-layer (0–6 km) mean wind. Third, when an upper-level feature is present and the convection is multicellular, clusters are favored relative to lines when the upper wave is not cut off (i.e., a wave structure promoting advection), provided that the deep-layer shear is not oriented at an optimal angle relative to a preexisting meridional boundary (as shown by prior research). Finally, if the convection is isolated, rotating storms may be favored for a broad area of PV advection, as measured by the relative equality of the zonal and meridional axes of the advection area, suggesting the importance of broader-scale destabilization. These findings are used to formulate testable hypotheses. Future model-based experiments using PV surgery or PV regression methods are proposed to clearly elucidate the dynamics behind these relationships.
Relationship between Precipitation Forecast Errors and Skill Scores of Dichotomous Forecasts
Authors: Tartaglione Nazario
Published: August 2009

In this paper, the sensitivities of the equitable threat score (ETS) and the true skill score (TSS), obtained with a 2 × 2 contingency table, to continuous precipitation forecast errors are investigated. Two idealized error models are adopted to describe the difference between forecasts and perfect observations. The observations consist of a time series generated by a multiplicative cascade model. The forecasts are constructed by adding the modeled errors to the observations. Two examples that are representative of two precipitation regimes are considered. Monte Carlo simulations of the modeled errors are performed to compute the score uncertainties.

Monotonic relationships between the precipitation forecast errors and the two skill scores are found. It is shown that the precipitation regime and the event frequency influence these relationships and the score uncertainties. The score uncertainties also depend on the forecast errors. Furthermore, it is shown that a relationship exists between the ETS and TSS when the forecast errors are very large. Results suggest that more information should be provided together with the scores and their uncertainties in order to provide a complete picture of the forecast performance.