Pelvic Angiography and the Diagnosis of Carcinoma of the Uterine Cervix

The hospital records and pelvic arteriograms of 31 patients with suspected, persistent or recurrent carcinoma of the uterine cervix were reviewed. The method used was found to be highly accurate in diagnosing and localizing tumors and was considered most helpful in suspected pelvic wall recurrences. Tumor encasement of the vessels can be mimicked by perivascular, postoperative and post radiation fibrosis. Tumor vessels and tumor stain are the better angiographic indicators of the presence of recurrent or persistent disease.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135472/1/ijgo00175.pd

Dissociation Between Attention and Consciousness During a Novel Task: an ERP Study

While consciousness and attention seem to be tightly connected, recent evidence has suggested that one of these processes can be present in the absence of the other. Recent researches showed that observers can pay attention to an invisible (unconscious) stimulus, and that a stimulus can be clearly perceived (seen) in the absence of attention. We have proposed a novel psychophysical task to explore neural correlates of top-down attention and consciousness. The task is meant to confirm that these two processes can occur independently of each other. EEG was recorded during realizations of the task and target-locked event-related potentials (ERPs) for masked and unmasked conditions were constructed. Time features corresponding to the P100, N150, and P300 components were extracted for each channel separately. Utilizing these features, we employed some common classifiers for classification of the fourfold state. Our task could separate attention and consciousness successfully through their neural correlates. The results indicate that some of the mentioned components changed when attention or consciousness occurs. By comparing difference waves in each condition separately, our results introduce new ERP correlates of attention and consciousness. We also revealed that parieto-occipital areas are the most relevant areas for dissociation between attention and consciousness. To our knowledge, this is the first time that these correlates are introduced in a separable mode, and that the classification accuracies are reported for this purpose.Як вважають, увага та усвідомлення тісно поєднані, проте результати недавніх досліджень дають підстави думати, що один із цих процесів може реалізуватися за відсутності другого. У новітніх експериментах виявилося, що спостерігачі можуть приділяти увагу невидимому (неусвідомлюваному) стимулу і що стимул може чітко розпізнаватися (диференціюватися) за відсутності уваги. Ми запропонували нове психофізіологічне завдання для дослідження нервових корелятів змін рівнів уваги та усвідомлення. Цільові ЕЕГпотенціали, пов’язані з подією (ППП), відводили в умовах пред’явлення замаскованих та незамаскованих візуальних патернів. Часові характеристики компонентів P100, N150 та P300 визначалися роздільно для відведень по кожному ЕЕГканалу. З урахуванням цих характеристик були використані певні загальні класифікатори для параметрів, спостережуваних у всіх чотирьох стимуляційних станах. У нашому тесті ефекти уваги та усвідомлення могли бути успішно розділені відповідно до їх нервових ЕЕГ-корелятів. Згідно з отриманими результатами, згадані вище компоненти ППП змінюються залежно від того, як проявляється увага або усвідомлення. Роздільне порівняння відмінностей між хвилями ППП для кожної з умов дозволило виявити нові кореляти уваги та усвідомлення, що відбиваються в ППП. Показано також, що тім’яно-потиличні кортикальні зони є структурами, найбільшою мірою пов’язаними з дисоціацією ефектів уваги та усвідомлення. Як ми вважаємо, ці кореляти вперше представлені з використанням методики, котра дозволяє їх розрізнити, і наведені дані щодо точності такої диференціації

Golestan cohort study of oesophageal cancer: feasibility and first results

To investigate the incidence of oesophageal cancer (EC) in the Golestan province of North-East Iran, we invited 1349 rural and urban inhabitants of Golestan province aged 35–80 to undergo extensive lifestyle interviews and to provide biological samples. The interview was repeated on a subset of 130 participants to assess reliability of questionnaire and medical information. Temperature at which tea was consumed was measured on two occasions by 110 subjects. Samples of rice, wheat and sorghum were tested for fumonisin contamination. An active follow-up was carried out after 6 and 12 months. A total of 1057 subjects (610 women and 447 men) participated in this feasibility study (78.4% participation rate). Cigarette smoking, opium and alcohol use were reported by 163 (13.8%), 93 (8.8%) and 39 (3.7%) subjects, respectively. Tobacco smoking was correlated with urinary cotinine (κ=0.74). Most questionnaire data had κ >0.7 in repeat measurements; tea temperature measurement was reliable (κ=0.71). No fumonisins were detected in the samples analysed. During the follow-up six subjects were lost (0.6%), two subjects developed EC (one dead, one alive); in all, 13 subjects died (with cause of death known for 11, 84.6%). Conducting a cohort study in Golestan is feasible with reliable information obtained for suspected risk factors; participants can be followed up for EC incidence and mortality

Highly Conductive Multifunctional Graphene Polycarbonate Nanocomposites

Graphene nanosheet bisphenol A polycarbonate nanocomposites (0.027 2.2 vol %) prepared by both emulsion mixing and solution blending methods, followed by compression molding at 287 C, exhibited dc electrical percolation threshold of approx.0.14 and approx.0.38 vol %, respectively. The conductivities of 2.2 vol % graphene nanocomposites were 0.512 and 0.226 S/cm for emulsion and solution mixing. The 1.1 and 2.2 vol % graphene nanocomposites exhibited frequency-independent behavior. Inherent conductivity, extremely high aspect ratio, and nanostructure directed assembly of the graphene using PC nanospheres are the main factors for excellent electrical properties of the nanocomposites. Dynamic tensile moduli of nanocomposites increased with increasing graphene in the nanocomposite. The glass transition temperatures were decreased with increasing graphene for the emulsion series. High-resolution electron microscopy (HR-TEM) and small-angle neutron scattering (SANS) showed isolated graphene with no connectivity path for insulating nanocomposites and connected nanoparticles for the conductive nanocomposites. A stacked disk model was used to obtain the average particle radius, average number of graphene layers per stack, and stack spacing by simulation of the experimental SANS data. Morphology studies indicated the presence of well-dispersed graphene and small graphene stacking with infusion of polycarbonate within the stacks

Fabrication of Graphene–Polyimide Nanocomposites with Superior Electrical Conductivity

We report on the fabrication of a novel class of lightweight materials, polyimide–graphene nanocomposites (0.01–5 vol %), with tunable electrical conductivity. The graphene–polyimide nanocomposites exhibit an ultra-low graphene percolation threshold of 0.03 vol % and maximum dc conductivity of 0.94 S/cm, which we attribute to excellent dispersion, extraordinary electron transport in the well-dispersed graphene, high number density of graphene nanosheets, and the π–π interactions between the aromatic moieties of the polyimide and the carbon rings in graphene. The dc conductivity data are shown to follow the power-law dependence on the graphene volume fraction near the percolation threshold. The ac conductivity of the nanocomposites is accurately represented by the extended pair-approximation model. The exponent <i>s</i> of the approximation is estimated to be 0.45–0.61, indicating anomalous diffusion of charge particles and a fractal structure for the conducting phase, lending support to the percolation model. Low-temperature dc conductivity of the nanocomposites is well-approximated by the thermal fluctuation-induced tunneling. Wide-angle X-ray scattering and transmission electron microscopy were utilized to correlate the morphology with the electrical conductivity. The lack of maxima in X-ray indicates the loss of structural registry and short-range ordering