bluuebunny/crossref_metadata_2025 huggingface dataset:
Controlling the particle size of amorphous iron nanoparticles
Authors: Cao X. , Koltypin Yu , Kataby G. , Prozorov R. , Gedanken A.
Published: September 2007

A method for controlling the particle size of amorphous iron, which was prepared by the sonication of iron pentacarbonyl [Fe(CO)5], is reported in this paper. The sonolysis was performed on neat Fe(CO)5 and its solutions in decane whose concentrations were 4 M, 1 M, and 0.25 M. The iron nanoparticles were subjected to TEM (Transmission Electron Micrograph), ESR (Electron Spin Resonance), TGA (Thermogravimetric Analysis), DSC (Differential Scanning Calorimctry), and Quantum Design SQUID magnetization measurement. The measured properties demonstrated a strong dependence on the concentration of the solution, e.g., particle size.
Precursor pathway to superconducting HgBa2(Ca0.86Sr0.14)2Cu3O8+δ with a Tc of 132 K
Authors: Hur Nam H. , Kim Nae H. , Park Yong K. , Park Jong C.
Published: September 2007

Polycrystalline samples of HgBa2(Ca0.86Sr0.14)2Cu3O8+δ (denoted as Hg-1223) were prepared by a precursor route, which involves the reaction between HgO and two precursors: Ba2CuO3+x and Ca0.14CuO2. X-ray powder diffraction analysis revealed that the Hg-1223 is isostructural with pristine HgBa2Ca2Cu3O8−δ and TlBa2Ca2Cu3O9−δ. The Hg-1223 has tetragonal symmetry with space group P4/mmm, and lattice parameters a = 3.8648(2) Å and c = 16.0319(2) Å. The as-synthesized Hg-1223 sample has a Tc of about 126 K. After annealing in an oxygen atmosphere at 280 °C for 10 h, the Tc increased to 132 K. Using this precursor pathway, Hg-1223 samples can be reproducibly synthesized.
NdBCO melting and solidification by a zone-melting method
Authors: Yao X. , Furuya K. , Nakamura Y. , Wen J. , Endoh A. , Sumida M. , Shiohara Y.
Published: September 2007

In the Nd-Ba-Cu-O system, a directional structure produced by a peritectic reaction has been observed. On heating, the sintered Nd1Ba2Cu3O6+δ (Ndl23) precursor formed a rod-like directional structure of Nd4Ba2Cu2O10 (Nd422) phase. These Nd422 rods became thicker from the melting interface to the solidified interface. The [100] direction of Nd422 crystal is parallel to the axis of Nd422 rod and the sample pulling direction. Moreover, Nd422 rod spacing was observed as a function of growth rate and decreased with an increase of growth rate. In addition, with an increase of growth rate, Ndl23 solidified interface morphologies changed from planar, cellular to equiaxed.
New method for rapid determination of crystal orientation via Kikuchi patterns
Authors: Van Bakel G.P.E.M. , Seidman D.N.
Published: September 2007

Kikuchi electron diffraction patterns are used extensively to determine crystal orientations via transmission electron microscopy (TEM) or in the electron backscattering pattern (EBSP) mode of scanning electron microscopy (SEM). A new method is presented that is capable of finding crystal orientations, the camera length, and the projection center from only one pattern per grain using a least-squares technique. This method eliminates the need to perform an alignment with a reference crystal in the backscattering mode. Application to a Σ = 13a silicon bicrystal is presented for TEM patterns and EBSP's. A complete analysis of the propagation of random measurement errors into the disorientation axis/angle pair is carried out. The root mean square deviation from the nominal disorientation angle is found to be 0.3°in the case of TEM and 0.5°in the case of EBSP. The root mean square inclination between the nominal and measured disorientation axis is found to be 1°in the case of TEM and 0.5°in the case of EBSP.
Investigation of structurally less-ordered areas in the Nb filaments of a heavily cold-rolled Cu-20 wt. % Nb in situ composite
Authors: Raabe D. , Hangen U.
Published: September 2007

A fiber-reinforced in situ metal matrix composite (MMC) consisting of copper (Cu) and 20 mass% niobium (Nb) was produced by large strain cold rolling. The rolled MMC revealed a very high strength combined with good electrical conductivity. The microstructure of single Nb filaments was investigated employing transmission electron microscopy (TFM). In heavily rolled specimens (∊max = 99.4%) randomly arranged dislocations as well as dislocation cells were observed. Furthermore, structurally less-ordered areas were discovered, the size of which frequently extended over the entire filament width. The shrinkage of these zones during heating was directly observed in the TEM. The impact of such structurally less-ordered areas on the strength was assessed. The discovery of the degradation of structural regularity in the Nb filaments of heavily cold-worked Cu-20 wt. % Nb shows that the underlying microstructural mechanisms responsible for the high strengths observed are far from being understood and that the strain-hardening models for Cu-based in situ composites currently discussed do not yet account for all relevant microstructural features.
Novel thin films of titanium dioxide particles synthesized by a sol-gel process
Authors: Nagpal V.J. , Davis R.M. , Desu S.B.
Published: September 2007

Novel thin films of ultrafine titanium dioxide particles dispersed in a matrix of hydroxypropylcellulose (HPC) polymer have been made on quartz and silicon substrates. The titanium dioxide particles were made by the hydrolysis and condensation of titanium tetraethoxide (TEOT) in solutions of HPC in a mixture of ethanol and water. HPC controlled the particle size by adsorbing at the particle surface during the growth process and generating repulsive steric forces. The TiO2/HPC composite films were transparent in the visible region and completely blocked ultraviolet radiation at 300 nm. These films were crack-free and uniform in composition and thickness. Transparent films of amorphous TiO2 were made by burning out the HPC at 500 °C. These films were highly uniform and had no macroscopic cracks. X-ray diffraction revealed a transition to the anatase form upon sintering at 600 °C. A film sintered at 700 °C had a porosity of 38%. The crystalline films remained transparent until they densified at 800 °C.
A model for microwave processing of compositionally changing ceramic systems
Authors: Skamser Daniel J. , Thomas Jeffrey J. , Jennings Hamlin M. , Lynn Johnson D.
Published: September 2007

A finite-difference model was used to simulate the temperature and composition distributions produced inside a specimen heated with microwave energy during a process involving a change in composition. The dielectric properties of the specimen change with composition, resulting in nonuniform microwave power absorption and steady-state temperature gradients. When the specimen becomes less lossy as it reacts, or if the changes in the microwave heating properties are gradual, the reaction proceeds relatively uniformly and the volumetric microwave heating creates an inside-out reaction profile leading to increased conversions for processes such as reaction bonding and chemical vapor infiltration (CVI). If the specimen becomes more lossy as it reacts, then the reaction proceeds nonuniformly with rapid reaction rates in the hottest parts of the specimen and little or no reaction in the cooler areas. The process may then occur as a reaction front which moves along the specimen, as with combustion synthesis. This type of processing has potential advantages and disadvantages depending on the system.
Phase characterization and burning rate in the self-propagating high-temperature synthesis of titanium borides
Authors: Ahn Chi-Won , Kwon Oh-Choon , Cho Kurn , Sohn Hong Yong , Lee Hyung-Bock
Published: September 2007

Combustion synthesis of titanium borides from Ti and B binary powder mixtures having molar ratios B/Ti of 1.9 to 2.4 resulted in the formation of TiB2 as the primary phase and TiB as the secondary phase. The amount of TiB decreased when the particle size of the Ti in the powder mixtures became small and when the B content was increased. The results are discussed in terms of the homogeneity of reactant powder mixtures and the degree of boron saturation of the Ti-B melt. The burning rate increased from 11 to 15 mm/s as the titanium particle size decreased from −100 to −325 mesh with the same boron particle size of –325 mesh.
Effects of Electroshock on Bluegill Feeding and Susceptibility to Predation
Authors: Wahl David H. , Einfalt Lisa M. , Callahan Sean P.
Published: September 2007

Electrofishing is a common technique used for the collection of freshwater fish. Although acute effects on fish (e.g., injury and mortality) have been examined, indirect behavioral effects (e.g., feeding and susceptibility to predation) have been relatively ignored. In the laboratory, we examined the effects of electroshock on food consumption by two size-classes of bluegills Lepomis macrochirus and on vulnerability to predation for one size-class. In aquaria, juvenile bluegills (47–55 mm) showed reduced feeding for up to 3 h postshock and no effects thereafter; adults (143–157 mm) exhibited reduced feeding for up to 12 h postshock. In 2.5-m-diameter pools, electroshocked bluegills were more vulnerable than control fish to predation by largemouth bass Micropterus salmoides when a predator was introduced immediately after electroshock, but vulnerability did not differ when the predator was introduced at 10 min postshock. We conclude that electrofishing inhibits feeding and increases vulnerability to predation but only for a short time. For bluegill populations, electrofishing can be an effective sampling technique for research and management with minimal negative consequences.
Prevalence of HBV-genotypes in immigrants affected by HBV-related chronic active hepatitis
Authors: Palumbo Emilio , Scotto Gaetano , Faleo Giuseppina , Cibelli Donatella Concetta , Saracino Annalisa , Angarano Gioacchino
Published: September 2007

BACKGROUND: The genetic heterogeneity of the HBV genome has been established and eight genotypes can be classified according to the criterion of >8% differences in the complete nucleotide sequence of the viral genome. AIMS: To evaluate the prevalence of HBV-infection in a population of immigrants and to determine in patients with detectable serum HBV-DNA the HBV-genotypes. METHODS: Between January 2005 and December 2005 a total of 556 immigrants were tested for HBsAg. In HBsAg positive patients the biochemical and virological activity of infection and the possible presence of co-infections (HCV, HDV, HIV) were evaluated. In patients with detectable serum HBV DNA, the HBV-genotype was determined by INNOLiPA. RESULTS: Among the 556 subjects tested, 60 (10.7%) resulted HBsAg positive. All were men, and 42 (70%) come from Africa, 10 (16.6%) from Asia and 9 (14.4%) from East-Europe. 28/60 (46.6%) patients presented normal ALT levels (<40 IU/L) and undetectable serum HBV DNA (<100 copies/mL in real-time PCR), while 32 (53.4%) patients had ALT levels above laboratory normal values and detectable serum HBV DNA. Genotype distribution was as follow: genotype E, 16 (50%), genotype D, 9 (28.1%), genotype A, 7 (21.9%). CONCLUSION: Our study evidences a moderate prevalence of HBV-infection in immigrants, particularly in sub-Saharan African people, and the potentiality of migratory flow in the introduction of genotype non-D hepatitis B virus, potentially characterized by a different natural history and, possibly, a different response to antiviral treatment.
MR imaging for evaluation of lesions of the cranial vault: a pictorial essay
Authors: Amaral Lázaro , Chiurciu Miriam , Almeida João Ricardo , Ferreira Nelson Fortes , Mendonça Renato , Lima Sérgio Santos
Published: September 2007

PURPOSE: A variety of diseases affect the calvaria. They may be identified clinically as palpable masses or incidentally in radiologic examinations. There are many diagnostic possibilities, including congenital, neoplastic, inflammatory and traumatic lesions. The purpose of this study is to illustrate the main calvarial lesions through MR imaging, their signal intensity and extension to neighboring sites. METHOD: A retrospective analysis of 81 cases, from November 1996 to July 2001, was conducted. The examinations were performed on a 1.5 T equipment and each one of the cases was pathologically proven. RESULTS: The results were: dermoid cysts [4 cases (5%)], epidermoid cysts [2 cases (2.5%)], cephalocele [14 cases (17.5%)], sinus pericranii [3 cases (3.7%)], leptomeningeal cysts [4 cases (5%)], Langerhans cell histiocytosis [10 cases (12.5%)], lipoma [4 cases (5%)], fibrous dysplasia [13 cases (16.2%)], osteoma [8 cases (10%)], hemangioma [1 case (1.2%)], meningioma [3 cases (3.7%)], chondrosarcoma [5 cases (6.2%)], hemangiosarcoma [1 case (1.2%)], multiple myeloma [3 cases (3.7%)], sarcomatous transformation of Paget disease [1 case (1.3%)], and metastasis [5 cases (6.2%)]. CONCLUSION: MRI identifies bone marrow abnormalities and invasion of adjacent tissues at an early stage. Therefore, it is an essential method when it commes to properly evaluating calvarial lesions.
Unruptured intracranial aneurysm presenting with epiletic seizure
Authors: Sena José C. , Reynier Yves , Alliez Bernard
Published: September 2007

Intracranial aneurysms are frequently present with subarachnoid hemorrhage.Less often they produce suggestive symptoms of cranial nerve dysfunction or intracranial tumor when very large. Their association with epilepsy has rarely been reported; such concurrence may not be a coincidence. When the patient presents with epileptiforme attacks the presence of an intracranial aneurysm is rarely considered. In this paper we report the case of a 45-years-old patient with an unruptured aneurysm of the middle cerebral artery with a 10 years history of epileptic seizure.
Multi-minicore disease revisited
Authors: Nucci Anamarli , Queiroz Luciano S. , Zambelli Helder J.L. , Martins Filho José
Published: September 2007

Multi-minicore disease (MmD) is an infrequent congenital myopathy, defined by structural changes in optic and electron microscopy, namely, multiple small areas lacking oxidative enzyme activity and focal disorganization of contractile proteins involving at most a few sarcomeres. The classical form of the disease manifests as more or less severe hypotonia and generalized weakness with predominance in axial and proximal limb muscles. Clinical variants also exist. Usually MmD is inherited as an autosomal recessive trait. Genetic heterogeneity is recognized and up to now mutations in the genes of RYR1 and SEPN1 have been detected. We record three unrelated cases of MmD. Case 1, with the classical benign form, was followed-up for 15 years. Case 2, presenting pharyngolaryngeal involvement and severe delay of head control, improved gradually, until independent gait was acquired at age of six years. A moderate restriction of daily life activities remains. Case 3, of antenatal-onset, was expressed by arthrogryposis of hands, predominance of scapular girdle deficit and a stable course after ten years on physiotherapy. All cases were selected by the characteristic morphological abnormalities in biceps brachii samples, including electron microscopy. Emphasis is given to case 2 due to type 1 fiber uniformity and mild endomysial fibrosis, posing a difficult differential diagnosis with congenital muscular dystrophy were it not for the significant number of multi-minicores.
Neurological manifestations of celiac disease
Authors: Siqueira Neto José Ibiapina , Costa Ana Carolina Leite Vieira , Magalhães Francisco George , Silva Gisele Sampaio
Published: September 2007

Celiac disease (CD/ Nontropicalsprue, gluten-sensitive enteropathy) is a malabsortive condition in which an allergic reaction to the cereal grain-protein gluten (present in wheat, rye and barley) causes small intestine mucosal injury. The onset is in the first four decades of life, with a female to male ratio of 2:1. It may be associated with a wide spectrum of neurological manifestations including cerebellar ataxia, epileptic seizures, dementia, neuropathy, myopathy and multifocal leucoencephalopathy. We report three patients with neurological manifestations related with CD: one with cerebellar ataxia, one with epilepsy and one with cognitive impairment. The diagnosis of CD was confirmed by serologic tests (antiendomysial and antigliadin antibodies) and biopsy of the small intestine. In two patients the neurological symptoms preceded the gastrointestinal abnormalities and in all of them gluten restriction failed to improve the neurological disability. Conclusion: CD should be ruled out in the differential diagnosis of neurological dysfunction of unknown cause, including ataxia, epilepsy and dementia. A gluten free diet, the mainstay of treatment, failed to improve the neurological disability.
Fibrilação atrial crônica, AVC e anticoagulação: sub-uso de warfarina ?
Authors: Cabral Norberto L. , Volpato Dalton , Ogata Tatiana Rosa , Ramirez Tenille , Moro Carla , Gouveia Sergio
Published: September 2007

OBJETIVO: Correlacionar acidente vascular cerebral (AVC) cardioembólico em portadores de fibrilação atrial (FA) crônica não valvular, potencialmente evitáveis, previamente acompanhados por cardiologistas, sem restrições ao uso da warfarina, com o grau de absorção das recomendações e limitações publicadas sobre anticoagulação e FA. MÉTODO: Registramos prospectivamente todos os casos de AVC internados em dois hospitais de Joinville.Na presença de FA, foi questionado aos pacientes se sabiam da existência da arritmia, freqüência de visitas a cardiologistas e uso prévio de warfarina. Posteriormente aplicamos um questionário transversal a 11 cardiologistas sobre o FA, anticoagulação e AVC. RESULTADOS: Entre 167 pacientes com AVC, 22 tinham FA prévia e AVC isquêmico. Destes, 15 tinham consultado previamente um cardiologista. Nove pacientes faleceram, sete tiveram alta anticoagulados e seis não receberam warfarina. O questionário evidenciou que 91% dos colegas conheciam as recomendações publicadas, mas somente 54 % deles consideravam-nas aplicáveis para pacientes do serviço público. CONCLUSÃO: A anticoagulação na FA reduz 68% o risco relativo para AVC/ano. Logo, 11 dos 22 pacientes poderiam ter evitado o evento. Extrapolando a incidência em 1997 e a população atual, podemos considerar que 4% de todos os AVC por ano em Joinville são potencialmente evitáveis.
A clinical epidemiological study of 251 cases of amyotrophic lateral sclerosis in the south of Brazil
Authors: Werneck Lineu Cesar , Bezerra Ruth , Silveira Neto Octavio da , Scola Rosana Herminia
Published: September 2007

OBJECTIVE: To study the clinical forms of amyotrophic lateral sclerosis (ALS) and the possible presence of risk factors in order to verify if there is any difference between cases in Paraná, Brazil. METHOD: We studied 251 cases, all of which fulfilled the diagnosis criteria proposed in El Escorial (WFN). Between 1977 and 2004, 157 male and 94 female patients were examined. RESULTS: 220 cases were classified as ALS-Spinal Onset (ALS-SO), 24 as ALS-Bulbar Onset (ALS-BO) and 7 as Familial ALS. The mean age at time of evaluation was 54.4±12.3 years, and symptoms had started 17.9±15.7months previously. In the group studied, statistical relationships were found between heavy occupations and males; previous surgeries and females; ALS-BO and dysphagia and dysarthria in females; and ALS-SO and males, cramps, weakness, muscle atrophy, hypertonia, increased deep tendon reflex and abnormal gait. CONCLUSION: The average age at time of evaluation was lower than that registered in the literature but similar to the Brazilian series. Domestic work and heavy occupations appear to be related to precocious perception of the symptoms by interference with daily functions. The socioeconomically higher classes seek medical care early. There was no relationship with exposure to toxic agents or trauma.
Central nervous system hemorrhage in thrombocytopenic patients: computed tomographic findings in 21 cases
Authors: Gasparetto Emerson L. , Benites Filho Paulo R. , Davaus Taísa , Carvalho Neto Arnolfo de
Published: September 2007

OBJETIVE: To describe the CT scan findings of 21 thrombocytopenic patients with central nervous system (CNS) hemorrhage. METHOD: Retrospective study of the computed tomography (CT) of 21 platelet-depleted patients with CNS hemorrhage. One patient presented two episodes of hemorrhagic episode with different intervals. The clinical data were obtained by the review of the medical records. Two radiologists analyzed the films and reached the decisions by consensus. The following findings were studied: type of bleeding, number of lesions, topography, laterality, size and associated findings. RESULTS: Intraparenchymal hemorrhage (IPH) was the most common findings, found in 20 cases, being six of them associated with subarachnoid and intraventricular hemorrhages. The size of the lesions varied between 1.8 and 10.5 cm. The parietal lobes were more commonly affected (n=11, 50%), followed by the temporal (n=7, 31.8%), frontal (n=7, 31.8%) and occipital (n=2, 9.09%) lobes. In 15 cases (68.2%) there was a single area of hemorrhage and in the remaining cases there were multiple hemorrhages. Associated findings were found in 20 cases. The most prevalent were edema (n=17, 77.3%), hydrocephalus (10, 45.4%) and midline shift (n=9, 41%). CONCLUSION: The most frequent CT scan findings in thrombocytopenic patients with CNS hemorrhage are single IPH, located mostly in the parietal, temporal and frontal lobes, with varied sizes and associated with edema, hydrocephalus and midline shift.
Reabilitação vestibular em pacientes com esclerose múltipla remitente-recorrente
Authors: Pavan Karina , Marangoni Bruna E.M. , Schmidt Kizi B. , Cobe Fernanda A. , Matuti Gabriela S. , Nishino Lúcia K. , Thomaz Rodrigo B. , Mendes Maria Fernanda , Lianza Sérgio , Tilbery Charles Peter
Published: September 2007

A esclerose múltipla (EM) é doença desmielinizante, inflamatória, que acomete a substância branca do sistema nervoso central, e sensações vestibulares anormais (vertigem, desequilíbrio) são freqüentes. A reabilitação vestibular (RV) é determinada por mecanismos de adaptações, substituições e compensações neurais. Este estudo avaliou a melhora da vertigem central ou periférica em pacientes com EM remitente-recorrente submetidos à RV (exercícios de Cawthorne-Cooksey), através da escala de Berg e Dizziness Handicap Inventory (DHI). Nesta amostra de 4 casos a RV, realizada em um período de 2 meses, demonstrou a melhora em 3 pacientes avaliados pela escala de Berg e em 2 pacientes quando avaliados pela DHI.
Early destructive lesions in the developing brain: clinical and electrographic correlates
Authors: Low Cristiane , Garzon Eliana , Carrete Jr. Henrique , Vilanova Luis Celso , Yacubian Elza Márcia T. , Sakamoto Américo C.
Published: September 2007

OBJECTIVE: Early brain insults can cause cavitary lesions including porencephaly (POR) and multicystic encephalopathy (MCE). The objective of this study was to investigate clinical and electrographic correlates associated to these types of destructive brain lesions. METHOD: Patients with POR and MCE were selected and submitted to clinical and Video-EEG monitoring. The following variables were analyzed: demographic data, type of lesion, presence of gliosis, perinatal complications, epilepsy, brain atrophy, and presence and frequency of epileptiform discharges. RESULTS: Twenty patients were included, 65% males, 35% females, ages ranging from 1 to 40 years, 14 with MCE and 6 with POR. Eighteen patients had hemiparesis, 19 had epilepsy (current or in the past), seven of them had refractory seizures, and 16 had epileptiform discharges. All patients with MCE had gliosis while only 2 with POR had it. CONCLUSIONS: No correlation was observed between type of lesion and clinical and electrographical outcome. However, a positive correlation was observed between frequency of discharges and presence of brain atrophy, and between MCE and gliosis.
Avaliação da vertical visual subjetiva em indivíduos brasileiros normais
Authors: Kanashiro Aline M. Kozoroski , Pereira Cristiana Borges , Maia Fernanda Martins , Scaff Milberto , Barbosa Egberto Reis
Published: September 2007

A função otolítica pode ser avaliada pela Vertical Visual Subjetiva (VVS) que determina a capacidade de um indivíduo julgar se objetos estão na posição vertical na ausência de outras referências visuais. O objetivo deste estudo foi avaliar a VVS em indivíduos brasileiros normais usando um aparelho portátil. As medidas da VVS foram realizadas em 160 indivíduos (16 a 85 anos). O valor médio da VVS foi obtido após dez ajustes. A VVS teve valores médios entre -2,0º e +2,4º (média=0,18º, e DP=0,77º). Não houve diferença entre as médias da VVS em relação à idade (teste de Kruskal-Wallis; p=0,40), mas as faixas etárias maiores tiveram variância maior (teste de Levene; p=0,016). Os valores da VVS encontrados neste estudo foram semelhantes aos registrados na literatura. Não houve diferença nas médias das inclinações da VVS de acordo com a idade, mas foi encontrada maior variância entre indivíduos mais idosos.
Intracranial meningiomas: magnetic resonance imaging findings in 78 cases
Authors: Gasparetto Emerson L. , Leite Claudia da Costa , Lucato Leandro T. , Barros Cristiano Ventorin de , Marie Sueli K.N. , Santana Pedro , Aguiar Paulo Henrique Pires de , Rosemberg Sérgio
Published: September 2007

OBJECTIVE: To present the magnetic resonance (MR) imaging findings of 78 patients with meningiomas diagnosed in a single institution. METHOD: 78 patients with histological proven intracranial meningioma were studied. There were 52 female and 26 male patients (median=56 years). All MR imaging examinations were performed with 1.5-T MR imaging unit with standard protocol. The images were studied by two neuroradiologists, who reached the decisions regarding the findings by consensus. RESULTS: Most of the tumors showed low signal on T1- (60%) and high signl on T2- (68%) and FLAIR (69%) weighted images. Also, the lesions showed heterogeneous signal on T1 (60%), T2 (68%) and FLAIR (64%) sequences. After contrast administration, 83% (n=65) of the tumors presented acentuated and 17% (n=13) showed moderate enhancement. The tumors were located in the frontal lobe in 44% of the cases, in the parietal lobe in 35%, the occipital lobe in 19% and the temporal lobe in 12% of the patients. Areas of vasogenic edema around the tumors were seen in 90% of the cases. Twenty six per cent of the cases showed bone infiltration, and the dural tail sign was seen in 59% of the tumors. CONCLUSION: Intracranial meningiomas usually show heterogeneous low signal on T1- and high signal on T2-weighted and FLAIR images, with intense enhancement after contrast administration. The frontal and parietal lobes are commonly affected. In addition, brain edema, dural tail sign and bone infiltration are the most frequent associated findings.
Cortical asymmetry: catching an object in free fall
Authors: Velasques Bruna , Machado Sergio , Portella Cláudio Elidio , Silva Julio Guilherme , Terra Patrícia , Ferreira Camila , Basile Luis , Cagy Mauricio , Piedade Roberto , Ribeiro Pedro
Published: September 2007

The main goal of the present study was to analyze theta asymmetry through quantitative electroencephalography (qEEG) when individuals were exposed to a sequential motor task, i.e. catching a ball. The sample was composed of 23 healthy subjects, male and female, between 25 and 40 years of age. A two-way factor Anova was applied to compare pre and post moments related to the balls' drop and scalp regions (i.e., frontal and parieto-occipital cortices). The first analysis of the frontal region compared electrodes in the left, right and left/right hemispheres combined, with the frontal midline electrode (FZ) included in the analysis. The results showed moment and region main effects. The second analysis compared left versus right hemisphere without the FZ site. The findings demonstrated an interaction effect between moment and region. The first parieto-occipital analysis, comparing left, right and central regions, with PZ included in all regions, showed main effects of moment and region. The second analysis, comparing left, right (without Pz) and central regions strictly demonstrated a region main effect. Thus, we observed an asymmetric pattern in the frontal cortex (i.e., planning and response selection) when the subjects were waiting for the balls' drop. Moreover, the left hemisphere seems to engage differently from the other regions when the central nervous system needs to prepare for a motor action. On the other hand, the parieto-occipital cortex, which is related to attentive processes, demonstrated a more asymmetric activity towards the right region which implies a participation of this area in cognitive strategies in this particular task. Taken together, we concluded that the adopted experimental approach can be useful to explore several others directions combining sensorimotor integration tasks with different pathologies, such as depression, Alzheimer's and Parkinson's diseases.
Changes in cortical relative power in patients submitted to a tendon transfer: a pre and post surgery study
Authors: Silva Julio Guilherme , Knackfuss Irocy Guedes , Portella Cláudio Elidio , Machado Sergio , Velasques Bruna , Bastos Victor Hugo do Vale , Queiroz Ricardo de Andrade , Neves Marco Antonio Orsini , Pacheco Mariana , Vorkapic Camila Ferreira , Cagy Mauricio , Piedade Roberto , Ribeiro Pedro
Published: September 2007

The aim of this study is analyze possible modifications in the cerebral cortex, through quantitative electroencephalography (qEEG) in patients submitted to a tendon transfer procedure (posterior tibialis) by the Srinivasan's technique. Four subjects (2 men and 2 women), 49.25 age average (SD±21.4) were studied. All subjects have been through surgical procedure due to leprosy and had, at least, two years of drop foot condition. The qEEG measured the electrocortical activity (relative power) between 8 and 25 Hz frequencies pre and post surgery. A paired t test analyzed all data (p<0,05). The results show significant alterations in the alpha relative power, electrodes F7 (p=0.01) and F8 (p=0.021). Altogether, based on findings of the current literature, we can conclude that the tendon transfer procedure suggests electrocortical alterations sensitive to specific qEEG bands.
Beta and alpha electroencephalographic activity changes after acute exercise
Authors: Moraes Helena , Ferreira Camila , Deslandes Andréa , Cagy Mauricio , Pompeu Fernando , Ribeiro Pedro , Piedade Roberto
Published: September 2007

Exercise has been widely related to changes in cortical activation and enhanced brain functioning. Quantitative electroencephalography (qEEG) is frequently used to investigate normal and pathological conditions in the brain cortex. Therefore, the aim of the present study was to observe absolute power alterations in beta and alpha frequency bands after a maximal effort exercise. Ten healthy young volunteers were submitted to an eight-minute resting EEG (eyes closed) followed by a maximal exercise test using a mechanical cycle ergometer. Immediately after the exercise, another identical eight-minute EEG was recorded. Log transformation and paired student's t-test compared the pre and post exercise values (p<0.05). Results indicated a significant absolute power increase in beta after exercise at frontal (Fp1, F3 and F4) and central (C4) areas, which might be related to increased cortical activation.
Relief of primary cervical dystonia symptoms by low frequency transcranial magnetic stimulation of the premotor cortex: case report
Authors: Allam Nasser , Brasil-Neto Joaquim Pereira , Brandão Pedro , Weiler Fernanda , Barros Filho Jairo de , Tomaz Carlos
Published: September 2007

OBJECTIVE: To evaluate the effect of low-frequency repetitive transcranial magnetic stimulation (rTMS) on the symptoms of a patient with primary segmental dystonia (PSD). METHOD: 1200 TMS pulses at a frequency of 1Hz, over the premotor cortex, with an intensity of 90% of the motor threshold (MT), using an eight-shaped coil; a total of 5 sessions were carried out. RESULTS: A reduction of 50 percent in the neck subset of the Burke, Fahn and Marsden torsion dystonia scale (BFM) was observed in our patient. CONCLUSION: The reduction in the BFM scale supports the concept that rTMS of the premotor cortex may reduce specific motor symptoms in PSD.
Lipoxygenase activity in Brazilian rice cultivars with variable resistance to leaf blast disease
Authors: Sandhu Sardul Singh , Mazzafera Paulo , Azini Luiz Ernesto , Bastos Cândido Ricardo , Colombo Carlos Augusto
Published: September 2007

Eight rice lines viz. CNA 8983, IAC-1732, IAC-1733, IAC-1748, IAC-1736, IAC-201, Volano and Arborea were evaluated in greenhouse for resistance against the leaf blast disease caused by Magnoparthe gracea. Lines CNA 8983, IAC 1732, IAC 1733 and IAC 1748 showed satisfactory resistance against the blast fungus while IAC 1736 and IAC 201 were intermediate and Volano and Arborea susceptible. All lines did not have lipoxygenase activity increased by methyljasmonic acid, however enzyme activity showed a positive relationship with resistance.
Heterosis and combining ability analyses from the partial diallel
Authors: Viana José Marcelo Soriano
Published: September 2007

This study discusses from the theoretical standpoint the analyses of heterosis and combining ability from the partial diallel. Aiming at to investigate the information provided by the genetic parameters, simulation studies were realized. The genetic model adjusted considered one gene, groups of six populations, three degrees of dominance (|d/a| equal to 0.5, 1 and 2, representing partial, complete and overdominance) and random allelic frequencies. For each degree of dominance 50 replications were performed. The model for heterosis analysis does not need to be restricted. The unrestricted model gives the same information as the restricted one. The model for combining ability is restricted. The restrictions of the partial-G2 model of GERALDI and MIRANDA-FILHO do not satisfy the parametric values of the specific combining ability effects. As in the complete diallel analysis, from the theoretical point of view there is no differences between the analysis of heterosis and combining ability. The analysis of differences in gene frequencies among the populations of the two groups is more efficient when it considers the heterosis and not the specific heterosis - or the specific heterosis effects or the effects of specific combining ability - mainly for genes whose frequencies are contrasting in the groups.
Produtividade e qualidade da silagem de milho e sorgo em função da época de semeadura
Authors: Von Pinho Renzo Garcia , Vasconcelos Ramon Correia de , Borges Iran Dias , Resende Adauton Vilela de
Published: September 2007

Com o objetivo de avaliar a influência de diferentes épocas de semeadura na produtividade e qualidade de cultivares de milho e sorgo para silagem e também verificar a possibilidade de substituição do milho pelo sorgo para produção de silagem, foram instalados experimentos em três épocas de semeadura, em área do Departamento de Agricultura da Universidade Federal de Lavras, no ano agrícola 2002/2003. Foram avaliados três grupos de cultivares - três cultivares de sorgo duplo propósito, três de sorgo forrageiro e três de milho, em três épocas de semeadura - 19/11/2002, 19/12/2002 e 18/1/2003). O delineamento utilizado foi o de blocos casualizados, em esquema fatorial 3 (grupos de cultivares) x 3 (épocas de semeadura), com quatro repetições. Avaliaram-se produtividade de matéria seca (MS), participação de panícula ou espiga na MS, e as porcentagens de proteína bruta, fibra em detergente neutro (FDN), fibra em detergente ácido (FDA) e lignina. Observou-se efeito significativo para cultivares e épocas de semeadura para todas as características avaliadas. Constatou-se a presença de interação cultivares*épocas para a produtividade de matéria seca (MS), participação de panícula ou espiga na MS e porcentagem de proteína bruta. Independentemente de época semeadura, com o milho se tem silagem com menor teor de fibra do que com qualquer tipo de sorgo e produtividade de matéria seca semelhante à do sorgo forrageiro e maior do que o sorgo duplo propósito. A maior produção de matéria seca de milho e sorgo, para forragem, é obtida na semeadura em novembro. Silagem de milho e sorgo de maior valor nutritivo é obtida na semeadura de janeiro. Do ponto de vista de produção e de qualidade nutricional da forragem, não é viável a substituição da silagem de milho pela de sorgo.
Produtividade de grãos e exportação de nutrientes de cultivares de arroz irrigadas por aspersão em conseqüência da época de semeadura
Authors: Crusciol Carlos Alexandre Costa , Soratto Rogério Peres , Arf Orivaldo
Published: September 2007

No sistema irrigado por aspersão, o uso de cultivares e épocas adequadas de semeadura podem possibilitar a obtenção de altos níveis de produtividade do arroz de terras altas. No entanto, são escassas as informações sobre a exportação de nutrientes pelos grãos dessa cultura nesse sistema de produção. Este trabalho objetivou avaliar o efeito da época de semeadura na produtividade e exportação de nutrientes pelos grãos de cultivares de arroz de terras altas (IAC 201, IAC 202, Carajás, CNA 7800 e CNA 7801), irrigados por aspersão. Os experimentos foram desenvolvidos nos anos agrícolas de 1995/1996 e 1996/1997, em Latossolo Vermelho distrófico, em Selvíria (MS). As semeaduras foram realizadas no início da segunda quinzena de setembro, outubro, novembro, dezembro, janeiro e fevereiro, de cada ano. Foi utilizado o delineamento de blocos ao acaso, em esquema de parcela subdividida, com quatro repetições. A época de semeadura influenciou a produtividade de grãos e exportação de nutrientes pelos grãos. A semeadura realizada em novembro proporcionou maior exportação de nutrientes por promover produtividades mais elevadas. Em épocas de semeadura antecipada (setembro), com a cultivar Carajás, a produtividade e a exportação de nutrientes foram superiores às demais; já nas semeaduras de outubro a dezembro, a cultivar CNA 7801 se destacou. No sistema irrigado por aspersão, é possível semeadura em fevereiro com produtividade acima 3.900 kg ha-1 utilizando as cultivares IAC 201 e Carajás.
Influência de seis porta-enxertos sobre a produção de clones superiores de seringueira
Authors: Cardinal Átila Bento Beleti , Gonçalves Paulo de Souza , Martins Antônio Lúcio Mello
Published: September 2007

Na cultura da seringueira [Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell.-Arg.] o método de propagação mais utilizado é a enxertia. No entanto, observa-se que a uniformidade esperada pela propagação vegetativa não é verificada em condições de campo, pois altas variações para as variáveis vigor e produção de borracha são detectadas em seringais comerciais, causados pela influência dos porta-enxertos utilizados. Com base nesse impedimento e na importância econômica da cultura para o Estado de São Paulo, este trabalho teve por objetivo principal indicar as melhores combinações de clones com porta-enxertos clonais para plantio no Estado, visando-se à alta produção de borracha. Foram analisados dados de cinco anos de produção de borracha seca de um experimento em parcela subdividida com quatro repetições, desenvolvido em Pindorama (SP). Os tratamentos constaram de seis porta-enxertos (GT 1; IAN 873; PB 235; RRIM 600; RRIM 701 e sementes não-selecionadas - SNS) e seis enxertos (GT 1; IAN 873; PB 235; PR 107; RRIM 600 e RRIM 701), totalizando 36 diferentes combinações, e os métodos de análise constaram de análise de variância individual e comparação de médias. Observou-se efeito pronunciado de porta-enxertos sobre a variável analisada, bem como comportamento diferencial entre as combinações testadas. A partir dos resultados, pôde-se concluir que os porta-enxertos PB 235, GT 1 e IAN 873 foram os que proporcionaram maiores rendimentos, podendo ser recomendados com segurança para as condições do Planalto Paulista; o uso de SNS como porta-enxerto não é recomendado, pois os rendimentos foram muito baixos quando comparado aos demais porta-enxertos testados.
Distribuição temporal da precipitação pluvial mensal observada no Posto Meteorológico do Instituto Agronômico, em Campinas, SP
Authors: Blain Gabriel Constantino , Piedade Sonia Maria de Stefano , Camargo Marcelo Bento Paes de , Giarolla Angélica
Published: September 2007

O conceito de alteração climática está atrelado à definição do termo clima. Assim, o primeiro passo no estudo de possíveis mudanças e de suas implicações nos diversos setores da sociedade e em especial na agricultura, é a correta caracterização do regime das variáveis meteorológicas de uma região, que não deve ser desassociada da dinâmica das condições do tempo. O objetivo deste trabalho é caracterizar a distribuição temporal de precipitação pluvial mensal no posto meteorológico do Instituto Agronômico localizado no município de Campinas (1890 a 2005), buscando-se tendências no regime desse elemento. A fim de avaliar possíveis mudanças na distribuição de freqüência de precipitação pluvial, os 116 anos de dados foram subdivididos em quatro períodos de igual duração: de 1890 a 1918 (P1); de 1919 a 1947 (P2); de 1948 a 1976 (P3) e de 1977 a 2005 (P4). Os 48 agrupamentos (quatro períodos de cada um dos 12 meses) foram, então, comparados por meio da função densidade de probabilidade gama. O grau de assimetria das distribuições pluviométricas mensais, evidenciado pelas grandes diferenças entre a média e a moda, mostrou ser discutível a consistência dos balanços hídricos climatológicos que utilizam valores médios mensais de chuva. O estudo não detectou tendência na variabilidade dos totais pluviométricos, na escala temporal utilizada, mostrando não ter havido mudanças significativas no regime de precipitação pluvial da série do posto meteorológico do Instituto Agronômico em Campinas (SP).
Desempenho de genótipos de trigo introduzidos do México no Estado de São Paulo
Authors: Biudes Gustavo Barnabé , Carmago Carlos Eduardo de Oliveira , Ferreira Filho Antonio Wilson Penteado , Azevedo Filho Joaquim Adelino
Published: September 2007

Os trigos mexicanos apresentam características agronômicas de interesse podendo ser recomendados para cultivo em condições de solo onde o alumínio não é um fator limitante ou serem utilizados como fontes genéticas em programas de melhoramento. O objetivo deste estudo foi avaliar o comportamento agronômico de 18 linhagens de trigo introduzidos do Centro Internacional de Melhoramento do Milho e Trigo, Cimmyt, México e duas cultivares-controle IAC-24 e IAC-289, em um experimento instalado em Monte Alegre do Sul (SP), em condições de solo corrigido e irrigado por aspersão, no período de 1999-2002. Avaliaram-se os seguintes caracteres: produção de grãos, altura de plantas, acamamento, ciclo da emergência ao florescimento, comprimento da espiga, número de espiguetas por espiga, número de grãos por espiga e por espigueta e massa de cem grãos. L1 (SERI M 82) e L15 (DESCONHECIDO) destacaram-se para produção de grãos. L1 destacou-se pelo ciclo tardio, alto número de espiguetas por espiga e de grãos por espiga e baixa massa de cem grãos e L15, pela precocidade para florescer e elevada massa de cem grãos. L3 (FASAN) e L16 (KAUZ*2//TC*6/RL5406(RL6043)/3/KAUZ) destacaram-se pelo porte baixo; L6 (PRINIA) e L8 (CHIL/BUC), pelas espigas compridas; L3, pelo alto número de espiguetas por espiga; L9 (MUNIA/KAUZ) pelo grande número de grãos por espiga e por espigueta, e L18 (CETTIA), pelos grãos mais pesados. Em pelo menos dois anos, houve tendência de se obter maior produção de grãos em plantas semi-anãs mais altas com ciclo mais curto. Plantas produtivas apresentaram grãos pesados, espigas compridas com maior número de espiguetas e de grãos.
Seletividade de inseticidas a Orius insidiosus
Authors: Torres Fabrícia Zimermann Vilela , Carvalho Geraldo Andrade , Souza Jander Rodrigues de , Rocha Liuz Carlos Dias
Published: September 2007

A utilização de produtos fitossanitários seletivos a inimigos naturais é importante para o sucesso de programas de manejo integrado de pragas em agroecossistemas. Objetivou-se investigar efeitos letais e subletais de inseticidas empregados para o controle de pragas da roseira sobre ovos e ninfas de quinto ínstar de Orius insidiosus (Say) Hemiptera: Anthocoridae, em condições laboratoriais. Formulações comerciais dos seguintes inseticidas foram diluídas em água destilada (concentração em g i.a./100 ml): endosulfam (0,021), formetanato (0,04), espinosade (0,0144) e deltametrina (0,0008). O tratamento testemunha foi somente com água destilada. Os bioensaios foram mantidos em câmara climática a 25 ± 2ºC, UR de 70 ± 10% e fotofase de 12 horas. Ovos do predador colocados em hastes de picão-preto (Bidens pilosa L.) foram imersos nas caldas inseticidas por cinco segundos. As ninfas de quinto ínstar do predador foram tratadas com os inseticidas em torre de Potter. O efeito total dos inseticidas foi estimado e enquadrados em classes toxicológicas de acordo com a IOBC. O inseticida deltametrina foi nocivo a ovos e ninfas de quinto ínstar de O. insidiosus; endosulfam, formetanato e espinosade foram levemente nocivos. Endosulfam e formetanato não afetaram negativamente as características reprodutivas de fêmeas oriundas de ovos tratados. Endosulfam e espinosade reduziram o número de ovos colocados por fêmeas oriundas de ninfas de quinto ínstar que receberam tratamento, e espinosade afetou negativamente a viabilidade desses ovos.
Modelo de vegetação potencial para a Região Nordeste decorrente da precipitação pluvial
Authors: Nascimento Robson de Sousa , Brito José Ivaldo Barbosa de
Published: September 2007

O presente trabalho aplica o modelo de Rey para calcular a vegetação potencial da Região Nordeste do Brasil e, assim, verificar se esse modelo identifica os principais tipos de vegetação dessa região. O método utilizado para calcular a taxa de Evapotanspiração (ET) é embasado na equação de Penman-Monteith. O modelo também inclui parâmetros fixados e as variáveis altura da vegetação e índice de área foliar (IAF). De modo geral, o modelo conseguiu reproduzir bem os biomas da região Nordeste do Brasil, principalmente a Caatinga, o Cerrado e a Mata Atlântica.
Efeito protetor do nifurtimox contra a reativação parasitária em pacientes cronicamente infectados pelo Trypanosoma cruzi e tratados com corticóide em virtude de afecções associadas
Authors: Rassi Anis , Amato Neto Vicente , Siqueira Astolpho Ferraz de , Leite Maurício Sérgio Brasil
Published: September 2007

Pacientes na fase crônica da doença de Chagas foram tratados com corticóide em virtude de afecções associadas e, a fim de tentar coibir reativação da infecção pelo Trypanosoma cruzi, houve uso concomitante do nifurtimox. Levando em conta o verificado em pesquisa anterior, quando corticóide de fato promoveu aumento da parasitemia detectada pelo xenodiagnóstico, pôde ser notado que o nifurtimox mostrou-se apto a evitar a citada acentuação parasitária, podendo tal constatação ser útil em procedimentos assistenciais, quando circunstancialmente estiverem presentes doença de Chagas e imunodepressão.