Miracle-dz/UniFAR-FTUs huggingface dataset:
Fifty Percent Reduced-Dose Cerebral CT Perfusion Imaging of Alzheimer’s Disease

To evaluate the value of 50% reduced-dose cerebral computed tomography (CT)perfusion imaging (CTPI) to show the perfusion abnormalities in Alzheimer’s disease (AD), as an attempt to develop a new imaging protocol with lower radiation dose to track the correlation of AD with regional blood flow abnormalities. A total of 52 patients with AD were assigned to the AD group and 28 healthy volunteers served as the control group. All participants were given a 50% reduced-dose cerebral CTPI (current was reduced from 160 to 80 mA) test by a multislice spiral CT scanner. Perfusion parameters of the bilateral frontal cortex, temporal cortex, hippocampus, and basal ganglia were measured, including the cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time to peak (TTP). Both the CBV and CBF values of the measured regions were significantly higher in the healthy control group than in the AD group (P < .05), while the MTT and TTP values of these cerebral areas were significantly lower in the healthy control group than in the AD group (P < .05). Four perfusion parameters, namely the MTT of the left frontal cortex, right temporal cortex, right basal ganglia, and right hippocampus, had the greatest sensitivity and a striking correlation with the incidence of AD. The blood flow per unit of time in the regions of interest was significantly lower in the AD group, which provides new evidence for the existence of microcirculation disturbance and ischemia in AD. The 50% reduced-dose cerebral CTPI scan is valuable to show the regional perfusion abnormalities in the patients with AD.
Barreiras e incentivos à aprendizagem organizacional: um estudo de caso

RESUMO O presente estudo constitui uma investigacao cientifica cujo objetivo e observar e identificar os agentes que facilitam ou dificultam a aprendizagem organizacional em uma empresa. Principia pela contextualizacao do objeto e do objetivo do estudo, seguida da justificativa para a escolha do tema de pesquisa. Apresenta uma revisao do referencial teorico disponivel, mediante analise conceitual e critica dos aspectos mais relevantes pertinentes ao tema. Na sequencia, descreve a opcao metodologica da pesquisa de campo, realizada na modalidade de pesquisa qualitativa exploratoria, que contempla um estudo de caso unico. A investigacao foi realizada na Petrobras, na qual se efetuaram analise documental, observacao nao participante e entrevistas com membros integrantes do corpo gestor da empresa. A visao dos entrevistados revela que a busca da empresa pela sobrevivencia diante das continuas mudancas e em um contexto evolutivo e propicia a aprendizagem, mas ha situacoes em que a aprendizagem e dificultada por barreiras impostas intencionalmente ou nao. Por se tratar de estudo de um caso especifico, a pesquisa nao possibilita que as conclusoes sejam estendidas a outras organizacoes de caracteristicas semelhantes, e tampouco que sejam generalizadas. Contudo, obteve-se uma visao sobre a forma pela qual o fenomeno da aprendizagem ocorre e pode ser facilitado ou prejudicado em uma organizacao.
Disruption of Plasmodium falciparum erythrocyte rosettes by standard heparin and heparin devoid of anticoagulant activity.

We have studied the ability of heparin to disrupt spontaneous rosettes formed between Plasmodium falciparum-infected and uninfected red blood cells, which has been proposed to have importance in the pathogenesis of cerebral malaria. Substantial variation in this activity was found among six laboratory stains of P. falciparum. Rosettes formed by three of these strains were highly sensitive to heparin (50% disruption at 0.5-25 micrograms/ml; 1 microgram/ml corresponds to 0.15 IU/ml). The rosettes formed by two other strains showed a much lower sensitivity (50% disruption at 700-2,500 micrograms/ml), while the rosettes formed by another strain were almost completely resistant to heparin (20% disruption at 6,500 micrograms/ml). The ability of heparin (65 or 650 micrograms/ml) to disrupt rosettes formed by 54 fresh Gambian isolates of P. falciparum also varied. Rosettes of 27 (50%) of the 54 isolates were disrupted to a significant degree (greater than or equal to 15%), while rosettes of the other 27 isolates remained unaffected at the concentrations tested. Heparin was fractionated by molecular weight and/or affinity for antithrombin III. We found that its property of rosette disruption was associated, to some extent, with size (high molecular weight) but not with its anticoagulant potential (affinity for antithrombin III). A heparin fraction with low affinity for antithrombin III and one with combined high molecular weight and low affinity for antithrombin III were as effective at disrupting rosettes as standard heparin, while a chemically modified (N-acetylated) high molecular weight-heparin fraction, similarly devoid of anticoagulant activity, lacked strong anti-rosette potential. (ABSTRACT TRUNCATED AT 250 WORDS)
Simulaciones avanzadas aplicadas al diseño de escáneres y mejora de la calidad de imagen en tomografía por emisión de positrones

Desde la aparicion de los primeros escaneres PET en los anos 70 del siglo pasado, la tomografia por emision de positrones se ha extendido de manera continuada en oncologia, cardiologia y neurologia. La utilizacion de esta tecnica en investigacion preclinica ha supuesto un gran desafio durante la ultima decada, en que se han desarrollado escaneres PET de muy alta resolucion para animales de laboratorio como ratones y ratas. En la actualidad se consiguen imagenes PET con una resolucion submilimetrica con sensibilidades superiores al 10 %. Esto ha sido posible gracias al desarrollo tecnologico de los equipos de deteccion de rayos gamma y la electronica de procesado. Asi mismo, la aparicion de computadores con gran capacidad de calculo, unido al perfeccionamiento de los algoritmos de reconstruccion y al uso generalizado de los metodos de simulacion Monte Carlo en todas las etapas del desarrollo de escaneres, ha supuesto un impulso muy importante en el desarrollo de la tecnica PET. En esta tesis doctoral se ha tratado de mejorar la calidad de las imagenes PET reconstruidas. Para ello se han utilizado de manera intensiva los metodos de simulacion Monte Carlo con el fin de entender a fondo los procesos que tienen lugar en la adquisicion de datos PET. La simulacion realista del PET nos ha permitido introducir mejoras en todas las fases del proceso de formacion de la imagen, desde el diseno del escaner y los detectores que lo componen hasta el calculo de la matriz del sistema utilizada en el proceso de reconstruccion, pasando por la adquisicion y procesado de datos y la introduccion de correcciones sobre los mismos. Gracias a ello, hemos conseguido imagenes con mejor resolucion espacial, mejor relacion senal-ruido y resultados de cuantificacion mas precisos y reproducibles.
Muscle‐specific gene expression during myogensis in the mouse

Over the past decade, significant advances in molecular biological techniques have substantially increased our understanding of in vivo myogenesis, supplementing the information that previously had been obtained from classical embryological and morphological studies of muscle development. In this review, we have attempted to correlate morphogenetic events in developing murine muscle with the expression of genes encoding the MyoD family of myogenic regulatory factors and the contractile proteins. Differences in the pattern of expression of these genes in murine myotomal and limb muscle are discussed in the context of muscle cell lineage and environmetal factors. The differences in gene expression in these two types of muscle suggest that no single coordinated pattern of gene activation is required during the initial formation of the muscles of the mouse. © 1995 Wiley‐Liss, Inc.
Poly-3-hydroxybutyrate-co-3-hydroxyvalerate containing scaffolds and their integration with osteoblasts as a model for bone tissue engineering

Nano/micro engineered polymeric materials offer expansive scope of biomimetic scaffolds for bone tissue engineering especially those involving electrospun biodegradable nanofibers incorporated with inorganic nanoparticles, thus mimicking the extracellular matrix of bone both structurally and chemically. For the first time, poly-3-hydroxybutyrate-co-3-hydroxyvalerate containing natural poly-(α, β)-DL-aspartic acid and inorganic hydroxyapatite nanofibers were fabricated using poly-3-hydroxybutyrate-co-3-hydroxyvalerate: poly-(α, β)-DL-aspartic acid at a ratio of 80:20 (w/w) added with 1% (w/v) of hydroxyapatite, by the process of electrospinning. The surface morphology, chemical, and mechanical properties of electrospun poly-3-hydroxybutyrate-co-3-hydroxyvalerate, poly-3-hydroxybutyrate-co-3-hydroxyvalerate/poly-(α, β)-DL-aspartic acid, and poly-3-hydroxybutyrate-co-3-hydroxyvalerate/poly-(α, β)-DL-aspartic acid/hydroxyapatite nanofibers were characterized by using field emission scanning electron microscope, Fourier transform infrared spectroscopy, and tensile tester, respectively. Human fetal osteoblasts were cultured on different nanofibrous scaffolds for evaluating the cell proliferation, alkaline phosphatase activity, and mineralization. Cells on poly-3-hydroxybutyrate-co-3-hydroxyvalerate/poly-(α, β)-DL-aspartic acid/hydroxyapatite scaffolds demonstrated higher proliferation (30.10%) and mineral deposition (37.60%) than the cells grown on pure poly-3-hydroxybutyrate-co-3-hydroxyvalerate scaffolds. Obtained results highlight the synergistic effect of poly-3-hydroxybutyrate-co-3-hydroxyvalerate, poly-(α, β)-DL-aspartic acid, and hydroxyapatite towards the enhancement of the osteoinductivity and osteoconductivity of human fetal osteoblasts, demonstrating the appropriate physicochemical and biological properties of poly-3-hydroxybutyrate-co-3-hydroxyvalerate/poly-(α, β)-DL-aspartic acid/hydroxyapatite nanofibers to function as a substrate for bone tissue regeneration.
Seasonal variations of accumulation and the isotope record in ice cores: a study with surface snow samples and firn cores from Neumayer station, Antarctica

Abstract At the German wintering base Neumayer, an intensive glacio-meteorological programme has been carried out during the last two decades. A complete meteorological dataset and data from surface snow samples, snow pits, firn cores and weekly accumulation measurements from a stake array are available. We first investigated the attenuation of the seasonal δ18O signal due to water-vapour diffusion in the snowpack. A comparison of surface snow samples and firn cores of different ages shows that only one-third of the seasonal δ18O signal of the surface snow samples remains in the cores after the first year. No further significant change in the amplitude of the seasonal δ18O signal is found later. Changes in the seasonal distribution of accumulation can lead to a bias in ice-core properties. This is studied on a short time-scale, using high-time-resolution data of accumulation, stable-isotope ratios and air temperature. Mean annual δ18O values from firn cores are not well correlated to annual mean air temperatures. However, the correlation is improved considerably by calculating an annual mean air temperature using monthly mean temperatures weighted by monthly accumulation. At Neumayer, it is mainly the cyclonic activity in late winter/early spring that determines whether and how the core data are biased.
Simple power line communication using switching converters

This paper proposes simple power line communication (PLC) method among DC-DC converters in DC distribution network system. In this method, current ripples in the converters' inputs are used as signal carrier whose frequency is modified as a function of information data. The modulator is easily realized by just adding a transistor and a resister to conventional PWM control circuit. Demodulator is also realized by simple analog circuit. With proposed method, the converters are capable of bidirectional data transmissions among all converters in the system. Circuit simulation results show the effectiveness of proposed method.
High expression of Pirh2, an E3 ligase for p27, is associated with low expression of p27 and poor prognosis in head and neck cancers

Downregulation of the cyclin‐dependent kinase inhibitory protein p27 is frequently observed in various cancers due to enhancement of its degradation. We recently reported that p53‐inducible protein with RING‐H2 domain (Pirh2) is a novel ubiquitin ligase for p27, required for the ubiquitylation and consequent degradation of p27 protein. However, there is no reports about the involvement of Pirh2 in both p27 downregulation and pathogenesis in human cancers. In the present study, we investigated them using cultured cell lines and surgical specimens derived from human head and neck squamous cell carcinoma (HNSCC). Depletion of Pirh2 by short interfering RNA induced accumulation of p27 and inhibited the growth of cultured HNSCC cells. By immunohistochemical analysis in 57 cases of HNSCC specimens, higher levels of Pirh2 expression (labeling index ≥ 60%) were found in 61.4% of HNSCC in comparison with 0% of normal mucosa. In addition, 83.3% of HNSCC with lower p27 expression (labeling index < 20%) displayed high Pirh2 levels. Therefore, Pirh2 expression was inversely correlated with p27 expression. Finally, Pirh2 expression was well correlated with poor prognosis. These findings suggest that Pirh2 overexpression may have an important role in the development and maintenance of HNSCC at least partially through p27 degradation, and that Pirh2 may be a potential molecular target for human HNSCC. (Cancer Sci 2009; 100: 866–872)
Comparison of DSP and FPGA realization of neural speed estimator for 2-mass system

In this paper two hardware applications of neural state estimator for the two-mass drive system are presented. One of them is realized in a Digital Signal Processor (DSP), and the second consists in parallel implementation of neural networks in a reconfigurable Field-Programmable Gate Array (FPGA) placed in CompactRIO controller. Described solutions of neural network implementations are used for the estimation of the load-side speed of an electrical drive with elastic joint. Several design and programming problems are presented. Developed neural estimators are tested in the laboratory drive. Application of the neural network with FPGA gives better results, especially on drive system transients. Obtained results show high accuracy of the load speed estimation with the presented neural estimator. High precision of calculation is also obtained in the presence of the load time constant changes.
Quantitative relation between myocardial viability and improvement in heart failure symptoms after revascularization in patients with ischemic cardiomyopathy.

BACKGROUND Studies of patients with coronary artery disease and left ventricular dysfunction have shown that preoperative quantification of myocardial viability may be clinically useful to identify those patients who will benefit most from revascularization both functionally and prognostically. However, the relation between preoperative extent of viability and change in heart failure symptoms has not been documented carefully. We assessed the relation between the magnitude of improvement in heart failure symptoms after coronary artery bypass surgery (CABG) and the extent of myocardial viability as assessed by use of quantitative analysis of preoperative positron emission tomography (PET) images. METHODS AND RESULTS We studied 36 patients with ischemic cardiomyopathy (mean left ventricular ejection fraction, 28 +/- 6%) undergoing CABG. Preoperative extent and severity of perfusion abnormalities and myocardial viability (flow-metabolism mismatch) were assessed by use of quantitative analysis of PET images with 13N ammonia and fluorine-18-deoxyglucose. Each patient's functional status was determined before and after CABG by use of a Specific Activity Scale. Mean perfusion defect size and severity were 63 +/- 13% and 33 +/- 12%, respectively. Total extent of a PET mismatch correlated linearly and significantly with percent improvement in functional status after CABG (r = .87, P < .0001). A blood flow-metabolism mismatch > or = 18% was associated with a sensitivity of 76% and a specificity of 78% for predicting a change in functional status after revascularization. Patients with large mismatches (> or = 18%) achieved a significantly higher functional status compared with those with minimal or no PET mismatch (< 5%) (5.7 +/- 0.8 versus 4.9 +/- 0.7 metabolic equivalents, P = .009). This resulted in an improvement of 107% in patients with large mismatches compared with only 34% in patients with minimal or no PET mismatch. CONCLUSIONS In patients with ischemic cardiomyopathy, the magnitude of improvement in heart failure symptoms after CABG is related to the preoperative extent and magnitude of myocardial viability as assessed by use of PET imaging. Patients with large perfusion-metabolism mismatches exhibit the greatest clinical benefit after CABG.
Pregnancy attributable to interaction between tetracycline and oral contraceptives.

Various drugs, including antibiotics, may be responsible for contraceptive failure and breakthrough bleeding in oral contraceptive (OC) users. A case history is reported of a woman who took OCs for 4 years without a problem. On October 16, 1978 she had a normal withdrawal bleed, and on October 20 she started the next course of Microgynon and also a 5-day course of tetracyline 500 mg 6 hourly for 3 days and also 250 mg 6 hourly for 2 days for sinusitis. She completed the course on October 24. She did not fail to take her OC, had no diarrhea or vomiting but had only a very light 2-day withdrawal bleed on November 14 and 15, 1978. She continued to take her OC for another 2 months until seen at the family planning clinic on January 8, 1979. Her uterus was then the size of at least a 12-week pregnancy. This would have corresponded with a previous menstrual period on about October 15 and indicated that she must have ovulated either when she was taking the tetracycline or in the week after. Termination confirmed the clinical assessment of the duration of pregnancy. The time course of this history of an OC user who had no problems for 4 years suggests that the tetracycline contributed to the contraceptive failure.
Cochlear Implant in Children

With the introduction of the cochlear implant (CI) device, hearing sensation has been restored to many profoundly deaf children. In this article, we will review new issues in cochlear implantation including candidacy, bimodal and bilateral cochlear implant, music and speech perception, and vestibular system involvement in cochlear implant. Abbreviations: IT-MAIS: Infant-Toddler version of the Meaningful Auditory Integration Scale; CI: Cochlear Implant; MAIS: Meaningful Auditory Integration Scale; FAPCI: functioning after Pediatric Cochlear Implantation; PBK: Phonetically Balanced Kindergarten; HINT-C: Hearing in Noise Test sentences for children; ITD: Interaural Time Differences; IID: Interaural Intensity Differences
Cardioinhibition can be the unique manifestation of epilepsy-like syncope.

SUMMARY Sudden death and syncope remain frequently unexplained despite numerous investigations. Here, we report the case of a pacemaker-implanted patient who presented during video-polysomnography recording a complete atrioventricular block simultaneously with an electrical seizure. Remarkably, the patient was completely asymptomatic. He had a history of recurrent syncope previously diagnosed as convulsive vasovagal syncope with cardioinhibition. This observation challenges the current belief that epilepsy-like syncope is a partial complex seizure systematically characterized by a stereotypical clinical course and ending suddenly with syncope. Physicians should know that syncope, followed by jerking movements, of cardiac origin is frequent and often misdiagnosed as epilepsy. Conversely, and although this is a rare condition, they should also be aware of the possibility of epilepsy-like syncope, even in the absence of any other principle symptoms evocative of epilepsy.
Hamiltonian derivation of a gyrofluid model for collisionless magnetic reconnection

We consider a simple electromagnetic gyrokinetic model for collisionless plasmas and show that it possesses a Hamiltonian structure. Subsequently, from this model we derive a two-moment gyrofluid model by means of a procedure which guarantees that the resulting gyrofluid model is also Hamiltonian. The first step in the derivation consists of imposing a generic fluid closure in the Poisson bracket of the gyrokinetic model, after expressing such bracket in terms of the gyrofluid moments. The constraint of the Jacobi identity, which every Poisson bracket has to satisfy, selects then what closures can lead to a Hamiltonian gyrofluid system. For the case at hand, it turns out that the only closures (not involving integro/differential operators or an explicit dependence on the spatial coordinates) that lead to a valid Poisson bracket are those for which the second order parallel moment, independently for each species, is proportional to the zero order moment. In particular, if one chooses an isothermal closure based on the equilibrium temperatures and derives accordingly the Hamiltonian of the system from the Hamiltonian of the parent gyrokinetic model, one recovers a known Hamiltonian gyrofluid model for collisionless reconnection. The proposed procedure, in addition to yield a gyrofluid model which automatically conserves the total energy, provides also, through the resulting Poisson bracket, a way to derive further conservation laws of the gyrofluid model, associated with the so called Casimir invariants. We show that a relation exists between Casimir invariants of the gyrofluid model and those of the gyrokinetic parent model. The application of such Hamiltonian derivation procedure to this two-moment gyrofluid model is a first step toward its application to more realistic, higher-order fluid or gyrofluid models for tokamaks. It also extends to the electromagnetic gyrokinetic case, recent applications of the same procedure to Vlasov and drift- kinetic systems.
The active leaning-based nearest neighbor mean distance novelty detection for large data set

In this paper, we propose a novel algorithm called active learning-based nearest neighbor mean distance (ALNNMD) novelty detection method. And this method can be applied to huge collections of data. ALNNMD is based on the framework of active learning. In each iteration it can choose the instance that most optimizes the current novelty detection model from the data pool, and then remove this instance to the training set. Thus, this method can just use few data samples to get a better novelty detection model, having the advantage of both reducing the size of data sets and optimizing the novelty detection model. Furthermore, a comparative experiment is carried out on the UCI data sets, pointing out the effectiveness of the proposed method.
Multidomain Collocation Methods for the Stream Function Formulation of the Navier-Stokes Equations

In this paper we present a new high-order method for the approximation of the Navier–Stokes equations in rectangularly decomposable domains. The governing equations are written in terms of a stream function. The resulting nonlinear fourth-order equation for the stream function is linearized using Newton’s method. An equivalent variational formulation of the linearized problem is derived from which a collocation scheme is constructed. Pseudospectral approximations which are $C^1 $ continuous at the interfaces between subdomains are used to approximate the solution. The approximations are shown to be $C^3 $ continuous at the interfaces asymptotically as the order of the polynomial approximation within each subdomain is increased. Numerical results are presented for a Stokes problem which show that the approximations are exponentially convergent. The method is used to solve the Navier–Stokes equations in an L-shaped domain for a range of Reynolds numbers. Stream function contours are displayed showing the ma.