British Library Electronic Table of Contents (United Kingdom)

In the autonomous unmanned helicopter landing problem, the position of the unmanned helicopter relative to the landmark is very important. A camera carried on the unmanned helicopter can capture an image of the landmark. In earlier research, it was reported that the camera position could be estimated by features extracted from the landmark image. However, it is necessary that the landmark image should be complete, or with only slight deficiencies, in order for this estimation process to be possible. In this article, we report on an innovative design for an estimation made from a camera position giving an incomplete single image of the landmark. An adaptive neuro-fuzzy inference system (ANFIS) is used to construct the mapping relation between the features of complete and incomplete landmark...

UK PubMed Central (United Kingdom)

AbstractObjectiveThis study aimed at determining the standing spinal landmark that corresponds to the inferior tip of the scapula and determining the accuracy of experienced...Full Text Available

UK PubMed Central (United Kingdom)

A historical account of the important landmarks in man's experience with the high altitude environment is followed by comments on the important stages in the understanding of its physiological effects....Full Text Available

UK PubMed Central (United Kingdom)

There is a requirement for a noninvasive technique to monitor stem cell differentiation. Several candidates based on optical spectroscopy are discussed in this review: Fourier transform infrared (FTIR)...Full Text Available

International Nuclear Information System (INIS)

In the case of injuries of the ankle joint, an imaging technique is expected to reveal the state of the bones, ligaments, and articular cartilage. Irrespective of novel imaging techniques, a plain radiography will be made in order to obtain a first picture of the injury. Examples are given, showing that further orientation along the Lauge-Hansen classification scheme of this type of injury helps to completely ascertain the damage to the Articulatio talocruralis. Further examinations applying specific methods such as arthrography will detect possible, isolated syndesmosis ruptures; lesions of the ligaments can also be directly detected by CT or MRT. The articular cartilage and its lesions can be visualized by a combination of CT and arthrography, but are better shown by the completely non-invasive MRT. This latter method also gives insight into pathological processes with the bone. It allows to detect necrotic bone regions and their ...

UK PubMed Central (United Kingdom)

We have established a reliable method to induce invasive and non-invasive carcinomas in the heterotopically transplanted urinary bladder of rats by repeated injection of N-methyl-N-nitrosourea (MNU),...Full Text Available

CERN Document Server

This paper deals with the computation of sectional curvature for the manifolds of~$N$ landmarks (or feature points) in~$D$ dimensions, endowed with the Riemannian metric induced by the group action of diffeomorphisms. The inverse of the metric tensor for these manifolds (i.e.~the cometric), when written in coordinates, is such that each of its elements depends on at most~$2D$ of the~$ND$ coordinates. This makes the matrices of partial derivatives of the cometric very sparse in nature, thus suggesting solving the highly non-trivial problem of developing a formula that expresses sectional curvature in terms of the cometric and its first and second partial derivatives (we call this Mario's formula). We apply such formula to the manifolds of landmarks and in particular we fully explore the case of geodesics on which only two points have non-zero momenta and compute the sectional curvatures of 2-planes spanned by the tangents to such geodesics. The ...

British Library Electronic Table of Contents (United Kingdom)

In this paper we focus on appearance features describing the manual component of Sign Language particularly the Local Binary Patterns. We compare the performance of these features with geometric moments describing the trajectory and shape of hands. Since the non-manual component is also very important for sign recognition we localize facial landmarks via Active Shape Model combined with Landmark detector that increases the robustness of model fitting. We test the recognition performance of individual features and their combinations on a database consisting of 11 signers and 23 signs with several repetitions. Local Binary Patterns outperform the geometric moments. When the features are combined we achieve a recognition rate up to 99.75% for signer dependent tests and 57.54% for signer indep...

UK PubMed Central (United Kingdom)

Tumour hypoxia represents a significant challenge to the curability of human tumours leading to treatment resistance and enhanced tumour progression. Tumour hypoxia can be detected by non-invasive and...Full Text Available

UK PubMed Central (United Kingdom)

Tumour hypoxia represents a significant challenge to the curability of human tumours leading to treatment resistance and enhanced tumour progression. Tumour hypoxia can be detected by non-invasive and...Full Text Available

International Nuclear Information System (INIS)

Bone integrity and mineral status were studied with a noninvasive method in uremic patients with severe secondary hyperparathyroidism undergoing maintenance hemodialysis.

Science.gov (United States)

Autofluorescence spectroscopy has been a widely explored technique for in vivo and noninvasive diagnosis of pre-cancer lesions in epithelium where 90% cancers originate. For extracting more accurate fluorescence information for cancer diagnosis, depth-resolved fluorescence measurements are crucial to assess NADH and FAD in non-keratinized epithelial layer and collagen in stromal layer, respectively. In this study, we achieved the depth-resolved fluorescence spectral measurements of squamous epithelial tissue based on confocal technique. We found that in non-keratinized epithelial layer the fluorescence signals excited at 405 nm were the combination of NADH and FAD fluorescence and could be used for evaluating the redox ratio. Moreover, we found that confocal time-resolved autofluorescence measurements of epithelial tissue with 405 nm excitations could provide the information on the layered tissue structure. All depth-resolved autofluorescence decays were accurately ...

International Nuclear Information System (INIS)

The frequency of peripheral pulmonary artery stenosis in patients after surgical repair of tetralogy of Fallot (TOF) ranges from 20 to 40%. This can be either primary or secondary to the surgical intervention. The influence of resulting lung perfusion alterations on the life quality of patients is difficult to predict. The aim of this study was to compare the utility of the diagnostic procedures in this group of patients, with particular focus on lung perfusion scintigraphy. This study comprised 104 patients who underwent repair of TOF at ages from 5 months to 25 years. The patients have been followed up for from 4.2 to 25 years. On the basis of chest X-ray peripheral pulmonary artery stenosis was suspected in 11 patients, in 12 on the basis of echocardiography examination. Lung perfusion scintigraphy has been performed on 87 patients. The disturbances in lung perfusion (mostly in the left lung) were show by means of lung perfusion scintigraphy in 43 (49%) of patients. In 27 of them ...

International Nuclear Information System (INIS)

The puborectalis syndrome is a defecation disorder supported by the nonrelaxation of puborectalis sling with consequent dyschezia. They report on a series of 98 patients submitted to clinical examination, defecography, anorectal manometry, electromyography and intestinal transit time studies. The main symptoms of puborectalis syndrome in their patients were incomplete defecation (89 %) and intermittent evacuation (63 %); 28 % of patients turned to finger defecation. In all patients, defecography showed an abnormal increase in puborectalis impression on the posterior anorectal wall, reduced anorectal angle opening under straining (mean value: 113 deg) and prolonged expulsion time with barium pooling in the ampulla (mean evacuation time: 38 seconds). Such anorectal abnormalities as rectal mucosal prolapse (47 cases) and anterior rectocele (36 cases) were also associated. In 33 of 98 patients (34 % of cases), sling assessment by bidigital palpation at preliminary clinical examination ...

Environmental Research Database

DescriptionAt present, measurement of rumen pH for differnt diets and feeding regimes is only possible through direct sampling of the rumen fluid. Such invasive procedures are not practical at the farm level and they have ethical implications for research programmes. This approach also has limitations to its reliability due to spatial variations in acidity within the rumen. Mathematical modelling offers a non-invasive real-time alternative for monitoring rumen pH, and the purpose of the research propose [continued...

Science.gov (United States)

Engines of Creation 2.0: The Coming Era of Nanotechnology -- Updated and Expanded, is an ebook-only version available for free to readers exclusively through WOWIO. In addition to an updated "look and feel" for the ebook, Engines of Creation 2.0 has been expanded to include the first known lecture on nanotechnology by physicist Richard Feynman, the landmark open letter debate between Dr. Drexler and the late nanotech pioneer and Nobel laureate Dr. Richard Smalley, analysis of the debate by Ray Kurzweil, and a number of new additions by Dr. Drexler, including his advice to aspiring nanotechnologists.

UK PubMed Central (United Kingdom)

Non-invasive electrophysiological and imaging techniques have recently made investigation of the intact behaving human brain possible. One of the most intriguing new research areas that have developed...Full Text Available

UK PubMed Central (United Kingdom)

The noninvasive assessment of cardiac function is of first importance for the diagnosis of cardiovascular diseases. Among all medical scanners only a few enables radiologists to evaluate the local cardiac...Full Text Available

UK PubMed Central (United Kingdom)

Acoustic pharyngometry is a relatively new noninvasive method that quantifies geometrically complexed pharyngeal dimensions. Our study aimed to investigate the predictability and usefulness of acoustic...Full Text Available

UK PubMed Central (United Kingdom)

Breath analysis is a powerful noninvasive technique for the diagnosis and monitoring of respiratory diseases, including asthma and chronic obstructive pulmonary disease (COPD). Nitric oxide...Full Text Available

UK PubMed Central (United Kingdom)

IntroductionColorectal cancer (CRC) is the second leading cause of cancer-related deaths, but currently available non-invasive screening programs have achieved only...Full Text Available

UK PubMed Central (United Kingdom)

The bulbar conjunctiva is one of the few areas in which blood flow in the peripheral vasculature can be directly and noninvasively observed in the human. Although extensive literature exists describing...Full Text Available

UK PubMed Central (United Kingdom)

IntroductionA rare side effect of antipsychotic medication is neuroleptic malignant syndrome, mainly characterized by hyperthermia, altered mental state, haemodynamic dysregulation,...Full Text Available

Science.gov (United States)

Cancer is a severe threat to human health. Early detection is considered the best way to increase the chance for survival. While the traditional cancer detection method, biopsy, is invasive, noninvasive optical diagnostic techniques are revolutionizing the way that cancer is diagnosed. Reflectance spectroscopy is one of these optical spectroscopy techniques showing promise as a diagnostic tool for pre-cancer detection. When a neoplasia occurs in tissue, morphologic and biochemical changes happen in the tissue, which in turn results in the change of optical properties and reflectance spectroscopy. Therefore, a pre-cancer can be detected by extracting optical properties from reflectance spectroscopy. This dissertation described the construction of a fiberoptic based reflectance system and the development of a series of modeling studies. This research is aimed at establishing an improved understanding of the optical properties of mucosal tissues by analyzing ...

Energy Technology Data Exchange (ETDEWEB)

The superconducting Tevatron accelerator at Fermi National Accelerator Laboratory (Fermilab) has surpassed twenty years of operation. The Tevatron is still the highest energy particle accelerator in the world and will remain so until the commissioning of the LHC in Europe later this decade. The Tevatron has operated in a Fixed Target mode, accelerating a proton beam into stationary targets/detectors, as well as a Colliding Beam mode, continuously colliding counter rotating beams of protons and antiprotons. Upon completion, the Tevatron cryogenic system became the world's largest helium refrigeration system. In 1993, the Tevatron cryogenic system was given the designation of International Historic Mechanical Engineering Landmark by the American Society of Mechanical Engineers. The operational history, experiences and statistics of the Tevatron, with an emphasis on the cryogenic system, is presented. Improvements, upgrades and current challenges of the ...

Energy Technology Data Exchange (ETDEWEB)

Advances in the theory and practice of stress corrosion cracking (SCC) are reviewed for the period 1965-1990. The proceedings of two landmark conferences are used as a basis for discussion: Ohio State University (1967) and Kohler, WI (1988). The discussion is developed around the following topics: metal-environment combinations, testing, fractography, metallurgical aspects, electrochemical aspects and crack chemistry, mechanisms, and prediction and mitigation. It is concluded that the main developments since 1967 are the recognition of the lack of specificity of SCC environments, the use of slow strain rate and fracture mechanics testing, quantitative SEM fractography, studies of grain boundary structure and compositions, transient electrochemistry of bare metal surfaces, measurement and modelling of crack chemistry, elaboration of several SCC models, including slip-dissolution and film induced cleavage, and mitigation by alloy development or anodic protection. ...

CERN Document Server

The discovery of atomic nucleus by E. Rutherford, at the beginning of the twentieth century, was the Nuclear Physics original landmark. From then, a series of experiments in which beams of particles composed of neutrons, protons and others, brought to collide with a nucleus in order to unravel its structure or produce artificial elements through nuclear transmutation, were triggered. With the development of experimental equipment, a number of other nuclear phenomena have been observed, such as beta decay, nuclear fission and fusion, M\\"oesbauer effect, etc. In view of the global political and economic landscape and the contemporary educational trends, this work suggest alternative topics in nuclear physics that can be discussed at the conceptual level in high school teaching, where the main focus lies in the historical and technological importance of such phenomena in society.

CERN Document Server

FastSLAM is a framework for simultaneous localization using a Rao-Blackwellized particle filter. In FastSLAM, particle filter is used for the mobile robot pose (position and orientation) estimation, and an Extended Kalman Filter (EKF) is used for the feature location's estimation. However, FastSLAM degenerates over time. This degeneracy is due to the fact that a particle set estimating the pose of the robot loses its diversity. One of the main reasons for loosing particle diversity in FastSLAM is sample impoverishment. It occurs when likelihood lies in the tail of the proposal distribution. In this case, most of particle weights are insignificant. Another problem of FastSLAM relates to the design of an extended Kalman filter for landmark position's estimation. The performance of the EKF and the quality of the estimation depends heavily on correct a priori knowledge of the process and measurement noise covariance matrices (Q and R) that are in most applications ...

Energy Technology Data Exchange (ETDEWEB)

Diagnostic x-ray spectrometry, a method based on x-ray fluorescence analysis, was used for noninvasive determination of iron and zinc in two distinct skin areas, representing predominantly dermal and epidermal tissues, in 56 patients with beta-thalassemia major and intermedia. The mean iron levels in the skin of patients with beta-thalassemia major and intermedia were elevated by greater than 200% and greater than 50%, respectively, compared with control values. The zinc levels of both skin areas examined were within the normal range. The data indicate that the rate and number of blood transfusions, which correlated well with serum ferritin levels (r . 0.8), are not the only factors that determine the amount of iron deposition in the skin (r less than 0.6). Other sources of iron intake contribute to the total iron load in the tissues, particularly in patients who are not given multiple transfusions. The noninvasive quantitation of skin levels ...

Energy Technology Data Exchange (ETDEWEB)

Purpose: The purpose of this study was to observe the process of fixation in liver specimens non-invasively by means of magnetic resonance. The fixation process of several formaldehyde-containing solutions was monitored with MRI and MRS at two different temperatures. Materials and Methods: Liver specimens were conserved in aqueous fixative solutions containing formaldehyde concentrations of 0.7, 1.8, 4 and 7.2% and at different temperatures of 5 C and 20 C. MRI was performed with T1-, T2- and PD-weighted TSE sequences, a 2D FLASH-sequence with and without magnetization transfer, and a FISP 3D-sequence on a clinical 1.5 Tesla MR whole-body unit, and MRS with {sup 1}H-spectroscopic methods (STEAM-sequence) on a 3 Tesla MR whole-body unit. Results: The diffusion of formaldehyde into the tissue was best identified on PD- and T1-weighted images as a band under the liver surface with increasing thickness, penetrating especially fast during the first three days. ...

Energy Technology Data Exchange (ETDEWEB)

A novel non-invasive approach to the on-line identification of BWR two-phase flow regimes is investigated. The proposed approach receives neutron radiography images of coolant flow recordings as its input and performs feature extraction on each image via simple and directly computable statistical operators. The extracted features are subsequently used as inputs to an ensemble of self-organizing maps whose outputs demonstrate swift and accurate classification of each image into its corresponding flow regime. The novelty of the approach lies in the use of the self-organizing map which generates the different classes by itself, according to feature similarity of the corresponding images; this contrasts traditional artificial neural networks where the user has to define both the number of distinct classes as well as to supply separate training vectors for each class.

ScienceCinema

...english ...

International Nuclear Information System (INIS)

During their life, intervertebral discs undergo degenerative changes which need not necessarily become lesions. Conventional X-rays do not provide information on the condition of the intervertebral discs, so MRT or CT are recommended as primary techniques as they are non-invasive. Invasive methods like myelography and especially discography should not be used unless a case is highly problematic. In infants with pains in the back, MRT should be carried out as early as possible as there is nearly always an organic cause. (orig.)

Science.gov (United States)

The non-invasiveness of autofluorescence technology may reduce sampling error and time delay for histopathology diagnosis. We establish biophotonic methods and guidelines to visualize and interpret early epithelial tissue changes that signify disease. Flexible and rigid fiber endomicroscopy instrumentation design parameters feasible for translation towards clinical use are in development.

International Nuclear Information System (INIS)

Purpose: To determine the value of MRI in the preoperative evaluation of chronic paranasal sinusitis and to compare the results with CT and intraoperative findings. Method/Materials: 42 patients with clinical signs of chronic paranasal sinusitis underwent MRI after CT evaluation on one day, with subsequent functional endoscopic sinus surgery on the next day. Coronary CT was obtained with 5-mm slices and table-feed in the prone position, while MRI was performed in the supine position with coronary T_2-TSE+pd and coronary and transverse HASTE, each with 5-mm slice thickness. Aquisition time in MRI was less than 8 minutes. Two radiologists reviewed the CT and MRI scans for signs of sinusitis and detection of anatomical landmarks. The results were correlated with the intraoperative findings. Results: MRI offered no artifacts of dental work and showed more often high quality pictures than CT. CT and MRI demonstrated a good correlation in the detection of mucosal ...

Energy Technology Data Exchange (ETDEWEB)

Magnetic resonance imaging (MRI) as a diagnostic imaging tool relies on the generation of magnetic fields, whereas the computerized tomography (CT) uses X-radiation. The fundamental principle of MRI is the magnetic resonance of paramagnetic atomic nuclei. These nuclei, as e.g. protons (= hydrogen nuclei), are aligned in required orientation by application of a strong magnetic field. Upon simultaneous application of an electromagnetic high-frequency field perpendicular to the axis of the basic magnetic field, and in response to periodical changing of the electromagnetic field at a given frequency, the originally aligned paramagnetic nuclei are forced into a movement similar to that of a ``whipping top``. When the resonance frequency is shut off, the nuclei return to their former, aligned positions, inducing a weak signal in a coil. The series of signals generated by multiple repetition of this process of excitation of nuclei and their return to aligned rest is used as input to a ...

Energy Technology Data Exchange (ETDEWEB)

In less than a decade computed tomography (CT scanning) had a profound impact on diagnostic radiology. Radiology of the orbit is no exception. As early as 1973, reports published in the radiological literature indicated that this new noninvasive imaging method was a highly effective way of demonstrating intraorbital mass lesions. As CT scanners became widely available, computed tomography became a significant adjunct to ophthalmological diagnosis. Today the main indications for CT scanning of the orbit are: (1) suspected mass lesions, most frequently presenting as exophthalmos, (2) orbital trauma, including foreign bodies, (3) some congenital anomalies, and (4) suspicion of extension into the orbit of extraorbital disease processes. Along with ultrasonography, another new noninvasive imaging technique, CT has replaced a number of more invasive and often less effective diagnostic methods, such as orbital pneumography, venography, and ...

British Library Electronic Table of Contents (United Kingdom)

Transplantation has emerged as the therapy of choice for many patients with end organ failure. One of the major goals is to tailor immunosuppressive therapy to the individual needs of every patient to balance the risk for rejection and over-immunosuppression. This will require diagnostic tools that can detect harmful processes in the allograft early, and that can be measured repeatedly. This review will consider recent advances in our understanding of the molecular nature of these processes and how this information is being utilized to design novel diagnostic assays to non-invasively monitor allografts. Highlighted is the need for large-scale prospective multi-centre studies to validate assays that show early promise in single centre studies.

Energy Technology Data Exchange (ETDEWEB)

A primary goal of noninvasive studies of human vision is to identify and characterize multiple visual areas in the human brain analogous to those identified in studies of nonhuman primates. By combining functional MEG measurements with images of individual anatomy derived from MRI, the authors hope to determine the location and arrangement of multiple visual areas in human cortex and to probe their functional significance. The authors have identified several different visual areas thus far which appear to be topographically organized. This paper focuses on the retinotopic characterization of the primary visual area (V1) in humans.

Energy Technology Data Exchange (ETDEWEB)

Bone integrity and mineral status were studied with a noninvasive method in uremic patients with severe secondary hyperparathyroidism undergoing maintenance hemodialysis. [Italian] Gli autori propongono un metodo non invasivo per studiare la densita' minerale e le caratteristiche geometriche e biomeccaniche dell'osso nei pazienti uremici affetti da iperparatiroidismo secondario grave.

International Nuclear Information System (INIS)

Supplementing the collection of artificial neural network methodologies devised for monitoring energy producing installations, a general regression artificial neural network is proposed for the identification of the two-phase flow that occurs in the coolant channels of boiling water reactors. The utilization of a limited number of image features derived from radiography images affords the proposed approach with efficiency and non-invasiveness. Additionally, the application of counter-clustering to the input patterns prior to training accomplishes an 80% reduction in network size as well as in training and test time. Cross-validation tests confirm accurate on-line flow regime identification.

Science.gov (United States)

Severe Crohn's Disease; Anxiety

International Nuclear Information System (INIS)

The direct injection of steam into a water pool is a method of heat transfer used in many process industries. The amount of research in this area however is limited to the nuclear industry, with applications relating to reactor cooling systems. Electrical resistance tomography (ERT), a low cost, non-invasive and which has high temporal resolution characteristics, can be used as a visualization tool for the resistivity distribution for the steam injection into water pool such as IRWST. In this paper, three dimensional resistivity distribution of the process is obtained through ERT using iterative Gauss-Newton method. Numerical experiments are performed by assuming different resistive objects in the water pool. Numerical results show that ERT is successful in estimating the resistivity distribution for the injection of steam in the water pool

British Library Electronic Table of Contents (United Kingdom)

Porous flow occurs in a wide range of materials and applies to many commercially relevant applications such as oil recovery, chemical reactors and contaminant transport in soils. Typically, breakthrough and pressure curves of column floods are used in the laboratory characterization of these materials. These characterization methods lack the detail to easily and unambiguously resolve flow mechanisms with similar effects at the core scale that can dominate at the aquifer or oil field scale, as well as the effects of geometry that control the flow at interfaces as in a perforated well or the inlet of an improperly designed column. Non-invasive imaging techniques such as MRI have been shown to provide a far more detailed characterization of the properties of the solid matrix and flow, but usu...

British Library Electronic Table of Contents (United Kingdom)

Summary Status epilepticus or other brain-damaging insults launch a cascade of events that may lead to the development of epilepsy. MRI techniques available today, including T2- and T1-weighted imaging, functional MRI, manganese enhanced MRI (MEMRI), arterial spin labeling (ASL), diffusion tensor imaging (DTI), and phase imaging, can detect not only damage caused by status epilepticus but also plastic changes in the brain that occur in response to damage. Optimal balance between damage and recovery processes is a key for planning possible treatments, and noninvasive imaging has the potential to greatly facilitate this process and to make personalized treatment plans possible.

International Nuclear Information System (INIS)

A noninvasive method is described for estimating local cerebral blood flow (LCBF) and local partition coefficients by means of computed tomographic scanning during inhalation of 30% stable xenon gas in oxygen. Time-dependent xenon concentrations in arterial blood and brain tissue during the wash-in and washout phases are used to calculate partition coefficients and LCBF values by means of a least-squares curve-fitting analysis. Control values for partition coefficient and LCBF obtained from control subjects with minor head trauma in the chronic stage were compatible with those in several past reports, and reproducibility was satisfactory. The theoretic grounds underlying this new method of curve-fitting analysis are discussed.

International Nuclear Information System (INIS)

Somatostatin receptor scintigraphy (SRS) is a valuable method for the detection of somatostatin receptor-positive lesions. Most gastrinomas (over-)express the somatostatin receptor subtype 2 which can be targeted by In-111 labeled Octreotide. Different studies show a high sensitivity of SRS for the localization and staging of gastrinomas. SRS seems to be superior to other non-invasive imaging modalities and has been proven to significantly contribute to patient management. However, the sensitivity depends on the size and exact localization of the tumors. Smaller lesions and lesions located in the duodenum show a significantly lower sensitivity. In any case, SRS belongs to the routine imaging procedure for gastrinomas for localization and staging and can also be used for evaluation of the tumor progression. (author)

International Nuclear Information System (INIS)

Fetal MRI examines non-invasively the unborn fetus. Ultrafast MRI sequences effectively suppress fetal motion. Multiple case reports and studies have shown that fetal MRI is particularly helpful in the evaluation of the central nervous system. The high contrast-to-noise ratio, the high spatial resolution, the multiplanar capabilities, the large field of view and the simultaneous visualisation of fetal and maternal structures have proven to be advantageous. Fetal MRI is particularly helpful in the evaluation of the normal and pathological development of the brain. Despite the fact that no side effects have been reported or are to be expected, the use of MRI during pregnancy is still limited to the second and third trimester of pregnancy. Magnetic resonance imaging contrast media are not to be used as it passes the placenta. Ultrasound remains the primary screening modality for fetal pathology; fetal MRI can serve as an adjunct or second-line imaging modality. ...

British Library Electronic Table of Contents (United Kingdom)

Objective:EEG source imaging provides important information regarding the underlying neural activity from noninvasive electrophysiological measurements. The aim of the present study was to evaluate source reconstruction techniques by means of the intracranial electrocorticograms (ECoGs) and functional MRI.Methods:Five source imaging algorithms, including the minimum norm least square (MNLS), LORETA with Lp-norm (p equal to 1, 1.5 and 2), sLORETA, the minimum Lp-norm (p equal to 1 and 1.5; when p=2, the MNLS method is mathematically equivalent to the minimum Lp-norm) and L1-norm (the linear programming) methods, were evaluated in a group of 10 human subjects, in a paradigm with somatosensory stimulation. Cortical current density (CCD) distributions were estimated from the scalp somatosensor...

British Library Electronic Table of Contents (United Kingdom)

Breath analysis could offer a non-invasive means of intravenous drug monitoring if robust correlations between drug concentrations in breath and blood can be established. In this study, propofol blood and breath concentrations were determined in an animal model under varying physiological conditions. Propofol concentrations in breath were determined by means of two independently calibrated analytical methods: continuous, real-time proton transfer reaction mass spectrometry (PTR-MS) and discontinuous solid-phase micro-extraction coupled with gas chromatography mass spectrometry (SPME-GC-MS). Blood concentrations were determined by means of SPME-GC-MS. Effects of changes in pulmonary blood flow resulting in a decreased cardiac output (CO) and effects of dobutamine administration resulting in...

British Library Electronic Table of Contents (United Kingdom)

The evaluation of hepatic histology and treatment of hepatitis C virus (HCV)/HIV-coinfected patients is rapidly changing. HCV has become an important cause of mortality in HIV-infected patients. Consequently, assessment of liver histology in all coinfected patients is particularly important. The evaluation of hepatic histology is shifting from reliance on the liver biopsy toward noninvasive modalities. Additionally, the importance of HCV-associated morbidity and mortality in HIV-infected patients has prompted increasing numbers of these patients to be HCV treatment candidates. Prospective trials in coinfected patients have reported lower sustained virologic responses compared to HCV-monoinfected patients. Consequently, the numbers of coinfected nonresponders to pegylated interferon/ribavir...

International Nuclear Information System (INIS)

A prospective comparative study with pathology was performed to assess the clinical value of Computed Tomography (CT) and endoscopic ultrasound (EUS) for nodal staging in lung cancer. A total of 329 nodal stations were dissected or sampled and 755 lymph nodes were examined at histology. On a pre-station basis, CT had greater sensitivity (74%) than EUS (56%), but EUS was more specific (83% versus 93%). The accuracy rates of the two techniques were similar. In conclusion, endoscopic ultrasound should be part of a routine preoperative diagnostic approach to non-small-cell lung cancer., because of its high specificity. Results can be improved when EUS and CT are combined., which suggests that these imaging modalities should be used together in selected patients for the noninvasive staging of non-small-cell lung cancer to identify local lymphatic spread.

International Nuclear Information System (INIS)

... carbon 14 cholera gels labelling membranes molecules proteins receptors

DEFF Research Database (Denmark)

Udgivelsesdato: 2008-Sep

Science.gov (United States)

An improved method for measuring distillation curves reveals the physicochemical properties of complex fluids such as fuels. PMID:20041713

Energy Technology Data Exchange (ETDEWEB)

The centromere is the most characteristic landmark of eukaryotic chromosomes. Centromeres function as the site for kinetochore assembly and spindle attachment, allowing for the faithful pairing and segregation of sister chromatids during cell division. Characterization of centromeric DNA is not only essential to understand the structure and organization of plant genomes, but it is also a critical step in the development of plant artificial chromosomes. The centromeres of most model eukaryotic species, consist predominantly of long arrays of satellite DNA. Determining the precise DNA boundary of a centromere has proven to be a difficult task in multicellular eukaryotes. We have successfully cloned and sequenced the centromere of rice chromosome 8 (Cen8), representing the first fully sequenced centromere from any multicellular eukaryotes. The functional core of Cen8 spans ~800 kb of DNA, which was determined by chromatin immunoprecipitation (ChIP) using an antibody ...

Science.gov (United States)

The Canadian Soldier Information Requirements Technology Demonstration (SIREQ TD) soldier modernization research and development program has conducted experiments to help determine the types and amount of information needed to support wayfinding across a range of terrain environments, the most effective display modality for providing the information (visual, auditory or tactile) that will minimize conflict with other infantry tasks, and to optimize interface design. In this study, seven different visual helmet-mounted display (HMD) designs were developed based on soldier feedback from previous studies. The displays and an in-service compass condition were contrasted to investigate how the visual HMD interfaces influenced navigation performance. Displays varied with respect to their information content, frame of reference, point of view, and display features. Twelve male infantry soldiers used all eight experimental conditions to locate bearings to waypoints. From a constant location, ...

International Nuclear Information System (INIS)

A study was performed to investigate the size of pharyngeal cavity and sexual differences between Korean adult mal e and female by introducing linear analysis of the lateral cephalogram. The radiograms were composed of 46 adult male aged 24.64 and 52 adult female aged 22.74 respectively. In order to study and measure the pharyngeal area, the following skeletal landmarks were selected: S,N,A,Ptm, B,H,H', M ,S-N, FH and CV, and the angle CV-FH was measured to provide a factor for correction of error resulting from improper he ad positioning of subjects, especially in the relative positions of A and H, while radiography. All points to be measured were projected at right angles to the Frankfort plane. For the purpose of measuring the anteroposterior dimensions of pharyngeal cavity the distances were measured in A-Ptm, A-S, S-Ptm and CV-H, and vertical measurements were made in SN-A, SN-PNS, SN-H' and M-H. The obtained results were as follows: 1. The pharyngeal cavity ...

International Nuclear Information System (INIS)

Several series of pyrimidine nucleosides were evaluated as part of a larger program to develop non-invasive brain imaging agents. The interaction of these antitumor/antiviral nucleosides with an NBMPR-sensitive murine erythroctye nucleoside transporter was evaluated by determining their inhibitory effect (K_i) on zero-trans influx of thymidine. Within each series of compounds, which had F, Cl, Br or I as halogen substituents, an increase in size of the halogen atom or a decrease in electronegativity decreased affinity for the transporter. Partition coefficients (P) of these pyrimidine nucleosides were measured to determine their potential to diffuse across the blood-brain-barrier (BBB). Most of the pyrimidine nucleosides had lower P values (log P < 0.9), and were considered to be poor candidates for simple diffusion across the BBB, although an active BBB transport mechanism for some nucleosides could be operative. For a given series, it was found that log P ...

Energy Technology Data Exchange (ETDEWEB)

A scintimetric study using Tc-99m MDP was made of 54 patients with delayed union, nonunion, or late segmental collapse of the femoral head, 4-92 months after femoral neck fracture. In radiographically verified collapse, the radionuclide uptake ratio between the femoral head on the fractured and on the intact side (HHR) was significantly higher than in fractures resulting in delayed union or nonunion. On the basis of scintimetric and radiographic findings, the patients with healing disturbances could be divided into three groups, characterized by the following features: (1) Satisfactory post-reduction position of the fracture without subsequent redisplacement and a high HHR, which as a rule turned out to be delayed union; (2) The same radiographic pattern but with a lower HHR, which in most cases resulted in nonunion; (3) Inadequate reduction or early redisplacement of the fracture with a high HHR, which resulted in nonunion. The fractional precision in discriminating between different ...

Energy Technology Data Exchange (ETDEWEB)

Non-invasive methods are described for estimating local cerebal blood flows (LCBF) and local partition coefficients (Llambda) during inhalation of 30 % stable xenon gas (Xe) in oxygen during CT scanning. After the denitrogenation with pure oxygen breathing, 30 % Xe is inhaled for four minutes to minimize subanesthetic effects with a rubber facemask and the delivery system of Xe. Local time-..delta.. Hounsfield units curve during the Xe wash-in and wash-out phase is utilized in order to calculate Llambda and LCBF using a least squares curve fitting analysis. Calculated Llambda and LCBF with the new method manifested reasonable distribution between the grey and white matters, and reproducibility was excellent in our study. Several case studies of patients with cerebral infarction are presented to demonstrate the characterization of Llambda and LCBF patterns in various tissues and theoretical grounds underlying the new method of curve fitting analysis are discussed.

International Nuclear Information System (INIS)

MRI provides a non-invasive diagnostic tool complementing echocardiography on one hand, and showing advantages over echocardiography, on the other hand, especially after corrective procedures. The multiple different MRI sequences need to be adapted to examinations of children and patients with congenital heart disease (CHD), and can be used to detect morphologic changes, blood-flow in the heart and thoracic vessels and diastolic or systolic function of myocardium. Several factors determine the success of the examination of a complex congenital heart disease or a postoperative situs. Pediatric radiologists and radiologists experienced in congenital heart diseases have to work in close cooperation. Echocardiography should be performed before MRI. The results of prior examinations and the clinical history of the patients, including possible palliative or reconstructive operations, must be available before MRI to guide the planning of the examination. With a systematic ...

Energy Technology Data Exchange (ETDEWEB)

The diagnosis of dialysis-related amyloid (AB-amyloid) has been based usually on clinical and radiological criteria. Following the discovery that beta 2-microglobulin was the major protein of this amyloid, we isolated and radiolabelled uremic plasma beta 2-microglobulin. After intravenous injection, gamma-camera images of selected joint areas were obtained from 42 patients who were on regular hemodialysis therapy. Positive scans involving the shoulder, hip, knee and carpal regions were found in 13 of 14 patients treated for more than 10 years and 10 of 16 patients treated for 5 to 10 years. Patients treated for less time had negative scans. Specificity was indicated by negative scans in non-amyloid inflammatory lesions in control hemodialysis patients. Up to 48-fold tracer enrichment was detected in excised AB-amyloid containing tissue as compared to amyloid-free tissue. These findings suggest that circulating radiolabelled beta 2-microglobulin is taken up by the amyloid deposits. This ...

International Nuclear Information System (INIS)

Functional imaging of the pharynx used to be the domain of cineradiography, CT and ultrafast CT. The development of modern MRI techniques led to new access to functional disorders of the pharynx. The aim of this study was to implement a new MRI technique to examine oropharyngeal obstructive mechanisms in patients with obstructive sleep apnea (OSA). Sixteen patients suffering from OSA and 6 healthy volunteers were examined on a 1.5 T whole-body imager ('Vision', Siemens, Erlangen Medical Engineering, Germany) using a circular polarized head coil. Imaging was performed with 2D flash sequences in midsagittal and axial planes. Patients and volunteers were asked to breathe normally through the nose and to simulate snoring and the Mueller maneuver during magnetic resonance imaging (MRI). Prior to MRI, all patients underwent an ear, nose and throat (ENT) examination, functional fiberoptic nasopharyngoscopy and polysomnography. A temporal resolution of 6 images/s and an in-plane resolution of ...

Energy Technology Data Exchange (ETDEWEB)

A methodology for assessing the impact of subacute concentrations of organometallic agents on bioenergetic and oxidative damage processes in animals, cells and energy transducing subcellular organelles is being developed. Several of the assays are noninvasive and thus lend themselves to human tests. At the whole-animal level we utilize a treadmill chamber where physiological parameters of exercising animals are monitored. These include parameters of whole animals' work performance such as oxygen consumption, carbon dioxide evolution and endurance. Oxidative damage can be monitored in experiments by analyzing expired air of the animals for ethane and n-pentane. These alkanes correlate with lipid peroxidation in vivo. At the cellular and subcellular levels, respiratory activity, lipid peroxidation and free radical species are assayed. Respiratory activity is measured in muscle homogenates and isolated mitochondria using substrates which feed into different ...

Energy Technology Data Exchange (ETDEWEB)

Modern imaging technologies visualize different aspects of disease in a non-invasive way. Considerable progress has been made in the fusion of images from different imaging modalities using software approaches. One goal of fusion software is to align anatomical and functional images and allow improved spatial localization of abnormalities. The resulting correlation of the anatomical and functional images may clarify the nature of the abnormality and help diagnose or stage the underlying disease. Whereas successful image fusion software has been developed for the brain, only limited success has been achieved for image alignment in other parts of the body. The development and current status of alternative approaches are presented. Dual-modality imaging is described with devices where two modalities are combined and mounted in a single gantry. The use of existing scanner technology ensures that no compromises are made in the clinical efficacy of either the anatomical ...

International Nuclear Information System (INIS)

Mammography has emerged as a reliable non-invasive technique for the early detection of breast cancer--the second leading cause of cancer-related mortality among American women. The radiographic appearance of the female breast consists of radiolucent (dark) regions due to fat and radiodense (light) regions due to connective and epithelial tissue. The amount of radiodense tissue can be used as a marker for predicting breast cancer risk. This paper presents the development of an algorithm for estimating the percentage of radiodense tissue in a digitized mammogram. The technique involves determining a dynamic threshold for segmenting radiodense indications in mammograms. Both the mammographic image and the threshold are modeled as Gaussian random variables. This work is intended to support a concurrent study at the Fox Chase Cancer Center (FCCC) exploring the association between dietary patterns and breast cancer risk. Mammograms have been obtained from an existing ...

Energy Technology Data Exchange (ETDEWEB)

A non-invasive, wide-band electromagnetic (EM) impedance difference system for shallow subsurface electrical structure characterization in environmental and engineering problems has been developed at the Lawrence Berkeley National Laboratory (LBNL). Electrical parameters of interest are electrical conductivity and dielectric permittivity that are deduced from the impedance difference data. The prototype system includes a magnetic loop transmitter, which operates between 0.1 MHz and 100 MHz, an electrical dipole antenna for observing the electric field, and a loop antenna for measuring the magnetic field.All antennas are mounted on a cart made of non-metallic material for easy movement of the whole array for profiling. Surface EM impedance difference is obtained by taking the difference of the ratios of the electric fields to the magnetic fields at selected frequencies at two different levels. Numerical simulations will be presented to verify this new approach. A ...

UK PubMed Central (United Kingdom)

BackgroundLate-onset sepsis in the premature infant is frequently revealed by severe, unusual and recurrent bradycardias. In view of the high morbidity and mortality...Full Text Available

Science.gov (United States)

... herbaceous and low succulents (mostly Sesuvium portulacastrum, also Ipomea sp., Euphorbia sp.). Local informants revealed that historic colonies ... vegetation (Sesuvium portulacastrum, Suriana maritima, ...

Science.gov (United States)

Evolution in Space Radio Telescopes Reveal Youngest Stellar Corpse Gas Clouds in Whirlpool Galaxy Yield Important Clues Supporting Theory on Spiral Arms Starbust-driven Winds...

UK PubMed Central (United Kingdom)

The rapidly emerging science of epigenetics and epigenomic medicine promises to reveal novel insights into the susceptibility to and the onset and progression of epileptic disorders. Epigenetic...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Intracapsular femoral neck fractures remain unsolved fractures even after improvement in techniques of diagnosis and internal fixation. Individuals who sustain displaced femoral neck fractures are at high risk of developing avascular necrosis and non-union. Although several methods for predicting the viability of femoral head have been reported, they are not effective or widely used because of unreliability, potential complications and technical difficulties. Dynamic MRI was introduced in the recent past as a simple, non-invasive technique to predict the femoral head viability after the femoral neck fractures. In this study role of dynamic MRI was studied in 30 patients with 31 intracapsular femoral neck fractures. Fractures were divided in to three types according to dynamic curve patterns on MRI evaluation and were followed up for 6 months to 2 years to observe the final outcome. Sensitivity, Specificity and the Accuracy of dynamic MRI in predicting vascularity ...

Energy Technology Data Exchange (ETDEWEB)

Purpose: To determine the value of MRI in the preoperative evaluation of chronic paranasal sinusitis and to compare the results with CT and intraoperative findings. Method/Materials: 42 patients with clinical signs of chronic paranasal sinusitis underwent MRI after CT evaluation on one day, with subsequent functional endoscopic sinus surgery on the next day. Coronary CT was obtained with 5-mm slices and table-feed in the prone position, while MRI was performed in the supine position with coronary T{sub 2}-TSE+pd and coronary and transverse HASTE, each with 5-mm slice thickness. Aquisition time in MRI was less than 8 minutes. Two radiologists reviewed the CT and MRI scans for signs of sinusitis and detection of anatomical landmarks. The results were correlated with the intraoperative findings. Results: MRI offered no artifacts of dental work and showed more often high quality pictures than CT. CT and MRI demonstrated a good correlation in the detection of mucosal ...

International Nuclear Information System (INIS)

Full text: Radiotherapy treatment planning (RTP) relies heavily on medical imaging. Until recently, the most important planning tool was the treatment simulator. The kilovoltage radiographic capabilities in a treatment simulator enabled the boundaries of treatment fields to be visualized with respect to bony anatomic landmarks. Perhaps the most important advance in treatment planning in recent years is the ability to visualize the passage of the beams with respect to a more accurate geometrical representation of the tumor and other soft tissue structures. This 'virtual simulation' uses a computer-based representation of a patient to determine the extent of the disease and the location of radiation sensitive normal tissue. Computer tomographic (CT) imaging produces a high-resolution three-dimensional representation of anatomy that can be correlated with other image sets such as magnetic resonance images (MRI) of function. Positron emission tomographic (PET) imaging ...

UK PubMed Central (United Kingdom)

BackgroundPuccinia striiformis f. sp. tritici is a fungal pathogen causing stripe rust, one of the most important wheat diseases worldwide. The...Full Text Available

UK PubMed Central (United Kingdom)

Forward and reverse genetic experiments have both played important roles in revealing critical aspects of mammalian signal transduction pathways in cell culture experiments. Only recently have we begun...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundDinoflagellates are unicellular, often photosynthetic protists that play a major role in the dynamics of the Earth's oceans and climate. Sequencing of dinoflagellate nuclear...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The temperature dependence of the dislocation mobility threshold is investigated on the basis of a dislocation model suggested by Frenkel-Kontorova. The critical value is obtained for the stress/temperature, corresponding to the dislocation depinning from its equilibrium position. The universal behaviour of a barrier height at finite stress and temperature is revealed and investigated.

UK PubMed Central (United Kingdom)

A community health survey of 438 individuals was taken to detect health problems related to high voltage electrical transmission among an adjacent residential population. Results revealed no significant...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundSensitization to house dust mite allergens is strongly correlated with asthma. Der p 7 elicits strong IgE antibody and T-cell responses in mite allergic...Full Text Available

UK PubMed Central (United Kingdom)

Assembly of infectious adenovirus particles requires seven functionally redundant elements at the left end of the genome, termed A repeats, that direct packaging of the DNA. Previous studies revealed...Full Text Available

Science.gov (United States)

This presentation from the 2006 PTEC Conference presents education research on topics in thermodynamics. Student responses to conceptual thermodynamics questions, and the conceptions they reveal, are presented. Tutorial materials developed to help students gain a better understanding of the topic are also presented.

Science.gov (United States)

... M. Taylor, T. Kurt Kyser. (2009) Feather isotope analysis discriminates age-classes of Western, Least, and Semipalmated sandpipers when plumage ... ...

UK PubMed Central (United Kingdom)

The brain maintains internal models of its environment to interpret sensory inputs and prepare actions. While behavioral studies demonstrated that these internal models are optimally adapted...Full Text Available

UK PubMed Central (United Kingdom)

alpha-actinins are actin microfilament crosslinking proteins. Vertebrate actinins fall into two classes: the broadly-expressed actinins 1 and 4 (actn1 and actn4)...Full Text Available

UK PubMed Central (United Kingdom)

Hibernators are unique among mammals in their ability to survive extended periods of time with core body temperatures near freezing and with dramatically reduced heart, respiratory, and metabolic rates...Full Text Available

UK PubMed Central (United Kingdom)

The sequence information available for homeodomains reveals that salt bridges connecting pairs 19/30, 31/42, and 17/52 are frequent, whereas aliphatic residues at these sites are rare and mainly restricted...Full Text Available

UK PubMed Central (United Kingdom)

A 4.5-year-old Holstein-Friesian cow underwent surgery because of left abomasal displacement. Intra-operative palpation of the pyloric region revealed a phytobezoar. The abomasum containing the phytobezoar...Full Text Available

UK PubMed Central (United Kingdom)

Human cytomegalovirus (HCMV) in clinical material cannot replicate efficiently in vitro until it has adapted by mutation. Consequently, wild-type HCMV differ fundamentally from the passaged strains...Full Text Available

UK PubMed Central (United Kingdom)

We reviewed 9 cases of pyogenic spondylodiscitis following percutaneous endoscopic lumbar discectomy (PELD). Microbiologic cultures revealed 6 causative organisms. Five patients were managed conservatively...Full Text Available

UK PubMed Central (United Kingdom)

Some strains of Bradyrhizobium japonicum have the ability to catabolize indole-3-acetic acid (IAA). Examination of this catabolism in strain 110 by in vivo experiments has revealed an enzymatic activity...Full Text Available

UK PubMed Central (United Kingdom)

Electrophoretic analysis of protein variation at the coagulation F13B locus has previously revealed three alleles, with alleles 1, 2, and 3 each being at high frequency in European,...Full Text Available

UK PubMed Central (United Kingdom)

Vulnerability to abused drugs is influenced by multiple genes unique to each drug as well as to risk genes for polydrug abuse. If several inbred mouse strains respond to different drugs similarly,...Full Text Available

UK PubMed Central (United Kingdom)

Sibling Paenibacillus dendritiformis bacterial colonies grown on low-nutrient agar medium mutually inhibit growth through secretion of a lethal factor. Analysis of secretions reveals...Full Text Available

UK PubMed Central (United Kingdom)

Hematopoiesis is the cumulative result of intricately regulated signaling pathways that are mediated by cytokines and their receptors. Studies conducted over the past 10 to 15 years have revealed that...Full Text Available

UK PubMed Central (United Kingdom)

Marine sediments are frequently covered by mats of the filamentous Beggiatoa and other large nitrate-storing bacteria that oxidize hydrogen sulfide using either oxygen or nitrate, which...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundThe Gram-negative bacterium Burkholderia pseudomallei (Bp) is the causative agent of the human disease melioidosis. To understand the evolutionary mechanisms...Full Text Available

UK PubMed Central (United Kingdom)

Bovine embryos can be generated by in vitro fertilization or somatic nuclear transfer; however, these differ from their in vivo counterparts in many aspects and exhibit a higher proportion of developmental...Full Text Available

UK PubMed Central (United Kingdom)

The role of pheromone biosynthesis activating neuropeptide (PBAN) in the regulation of pheromone biosynthesis of several female moth species is well elucidated, but its role in the males has been a...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundNew technology allows more precise definition of structural alterations of all retinal layers although it has not been used previously in cases of optic...Full Text Available

UK PubMed Central (United Kingdom)

Rumen-cannulated cows (n = 4) were fed successively silage made from either conventional or genetically modified (GM) maize. Results revealed no effects of GM maize on the dynamics...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundThe transcription factor Pax6 is essential for the development of the central nervous system and it exerts its multiple functions by regulating the expression of downstream...Full Text Available

UK PubMed Central (United Kingdom)

BACKGROUND AND AIMS:In view of increasing therapeutic efficacy, the delivery of hepatitis C virus (HCV) antiviral treatment is expected to increase. Yet practical experience reveals...Full Text Available

UK PubMed Central (United Kingdom)

AbstractX-ray diffraction analysis of pressure-induced structural changes in the Aequorea yellow fluorescent protein Citrine reveals the structural basis for the continuous...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundInterest in lycopene metabolism and regulation is growing rapidly because accumulative studies have suggested an important role for lycopene in human health promotion....Full Text Available

UK PubMed Central (United Kingdom)

Computer-assisted analysis revealed a striking sequence similarity between the putative 24-kDa protein (p24) encoded by open reading frame (ORF) 5 of beet yellows closterovirus and the coat protein...Full Text Available

UK PubMed Central (United Kingdom)

Molecular analysis of the amo gene cluster in Nitrosococcus oceani revealed that it consists of five genes, instead of the three known genes, amoCAB....Full Text Available

UK PubMed Central (United Kingdom)

In Iran, microscopic examination of skin scrapings from 2202 individuals with clinically diagnosed cutaneous leishmaniasis (CL) lesions revealed the presence of amastigotes in 1123 cases (51.0%). Bacteriological...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundHistone post-translational modifications are critical for gene expression and cell viability. A broad spectrum of histone lysine residues have been identified in yeast...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundThe successful interaction of bacterial pathogens with host tissues requires the sensing of specific chemical and physical cues. The human gut contains a huge number of...Full Text Available

International Nuclear Information System (INIS)

A correlation investigation was carried out on the series of atomic coordinates (MPV) and temperature factor (T _f), respectively for human hemoglobin and HIV-1 protease protein main chains. The MPV series revealed resemblances to the corresponding T _f series. Each minor or major peak in a series had a corresponding peak in the related series. This brings a qualitative evidence for the connection of the two parameters. The series were further subjected to spectral and detrended fluctuation analysis which all revealed long-range correlation properties. This combined analysis revealed that the data were controlled both by the correlation of stationary fluctuation and trends or non-stationary contribution to correlation. The correlation of all MPV series was found to be much less sensitive to ligand binding than the corresponding T _f series. Thus the long-range correlation properties of the protein main chain structure and ...

UK PubMed Central (United Kingdom)

BackgroundProteins may evolve through the recruitment and modification of discrete domains, and in many cases, protein action can be dissected at the domain level. PDZ domains are...Full Text Available

UK PubMed Central (United Kingdom)

Picocyanobacteria of the genus Synechococcus are important contributors to marine primary production and are ubiquitous in the world's oceans. This genus is genetically diverse, and...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Results of a survey conducted by Concawe on 75 oil refineries in Europe show that the total quantity of waste requiring disposal in 1986 was 0.5 million metric tons. This quantity of waste is but 0.13% of the total refinery throughput of 387 million metric tons during 1986. The survey revealed a wide range of disposal costs, depending on the particular properties of the waste and local conditions. A summary of total waste generation and how the waste is disposed of is shown. Details on the types of waste disposed, the disposal methods used, and the costs of disposal are detailed in this excerpt from the Concawe survey.

International Nuclear Information System (INIS)

Analysis of data on seedling traits from 20 diverse genotypes revealed significant differences fro most of the seedling traits. Significant estimates of broad-sense heritability were observed for VI, ERI, FRTW, DRTW and R/S ratio. Genetic advance was maximum for VI,ERI and E%. The correlation of VI with ERI and R/S ratio was negative and significant, whereas it was positive and significant with E%, FSHW and DSHW. Characterization of the sorghum genotypes according to Anderson's Metro glyph Statistics revealed five different groups for seedling trails. (authors)

Energy Technology Data Exchange (ETDEWEB)

Characterization and performance testing of a prototype DWPF Melter No.2 Dome Heater Bus Bar are described. The prototype bus bar was designed to address the design features of the existing system which may have contributed to water leaks on Melter No.1. Performance testing of the prototype revealed significant improvement over the existing design in reduction of both bus bar and heater connection maximum temperature, while characterization revealed a few minor design and manufacturing flaws in the bar. The prototype is recommended as an improvement over the existing design. Recommendations are also made in the area of quality control to ensure that critical design requirements are met.

Energy Technology Data Exchange (ETDEWEB)

The objective of this study was to compare contrast-enhanced magnetic resonance angiography (CE MRA) and multislice computed tomographic angiography (MS CTA) in the follow-up of thoracic stent-graft placement. The CE MRA and MS CTA were performed following nitinol stent-graft treatment due to thoracic aneurysm (n=4), intramural bleeding (n=2) and type-B aortic dissection (n=5). Corresponding evaluation of arterial-phase imaging characteristics focused on the stent-graft morphology and leakage assessment. Stent-graft and aneurysm extensions were comparable between both techniques. Complete exclusion (aneurysm, n=4; dissection, n=2) was assessed with high confidence with CE MRA and MS CTA. Incomplete exclusion (intramural bleeding, n=2; dissection, n=3) was assigned to lower confidence scores on CE MRA compared with MS CTA. On CE MRA the stent-graft lumen demonstrated an inhomogeneous signal, the stent struts could not be assessed. The CE MRA can be used as alternative ...

Energy Technology Data Exchange (ETDEWEB)

The purpose of the workshop was to determine the status of the field, to define instrumental and computational requirements, and to establish minimum specifications required by possible users. The most important message sent by implementers was the remainder that CMT is a tool. It solves a wide spectrum of scientific problems and is complementary to other microscopy techniques, with certain important advantages that the other methods do not have. High-resolution CMT can be used non-invasively and non-destructively to study a variety of hierarchical three-dimensional microstructures, which in turn control body function. X-ray computed microtomography can also be used at the frontiers of physics, in the study of granular systems, for example. With high-resolution CMT, for example, three-dimensional pore geometries and topologies of soils and rocks can be obtained readily and implemented directly in transport models. In turn, these geometries can be used to calculate ...

Energy Technology Data Exchange (ETDEWEB)

A non-invasive diagnostic tool that could identify malignancy in situ and in real time would have a major impact on the detection and treatment of cancer. We have developed and are testing early prototypes of an optical biopsy system (OBS) for detection of cancer and other tissue pathologies. The OBS invokes a unique approach to optical diagnosis of tissue pathologies based on the elastic scattering properties, over a wide range of wavelengths, of the microscopic structure of the tissue. The use of elastic scattering as the key to optical tissue diagnostics in the OBS is based on the fact that many tissue pathologies, including a majority of cancer forms, manifest significant architectural changes at the cellular and sub-cellular level. Since the cellular components that cause elastic scattering have dimensions typically on the order of visible to near-IR wavelengths, the elastic (Mie) scattering properties will be strongly wavelength dependent. Thus, morphology ...

International Nuclear Information System (INIS)

Magnetic resonance (MR) imaging was performed in 26 patients with Ewing's sarcoma of bone preceding and following neoadjuvant chemotherapy, to assess tumour response non-invasively prior to surgery. T1- and T2-weighted spin echo images were obtained. Changes including intra- and extramedullary signal intensities, tumour demarcation, tumour volume and the appearance of residual extramedullary tumour were compared with histophathology of the resected specimens. Reduction of tumour volume was significantly higher in good responders. Other single parameters did not correlated with histologic tumour response. However, when several MR parameters summarized in a classification system were combined, a positive correlation with histopathologic response was found. A limited decrease of tumour volume (<25 %) and/or residual soft tissue mass following chemotherapy correlated with a poor response. An inhomogeneous, well-defined cuff of abnormal tissue encircling the bone ...

Energy Technology Data Exchange (ETDEWEB)

The treatment of bony, osteochondral, and ligamentous injuries of the tibio-talar requires precise preoperative planning by radiological investigation. This is essential to a correct understanding of the underlying pathology and will allow a proper classification of the injury, which is the basis of treatment. Conventional radiography using anteroposterior and lateral X-rays with comparative views of the noninjured side and, if necessary, rotated spot views and tomography are of high value especially in osteochondral fractures of the talus. Intraoperative control images in both planes after osteosynthesis are mandatory. For evaluation of the postoperative course and severity of arthrosis formation, the classification system of Bargon has proved its worth. In addition, tomography of the tibio-talar joint in two planes is useful especially in tibial pilon fractures, some malleolar fractures, and peripheral talar fractures. In talar fracture dislocations with concomitant compartment ...

Energy Technology Data Exchange (ETDEWEB)

The /sup 13/C-AP breath test is shown to be a convenient, noninvasive method to monitor velocity and capacity of P450-dependent AP N-demethylation in infancy and childhood. According to /sup 13/C-AP breath tests, neonates have a very low capacity to eliminate /sup 13/CO/sub 2/, which is only 15 to 21% of the activity in adults. During the first year of life AP N-demethylation increases to reach its maximum at about 2 years; afterwards a slight decrease occurs. In 25 neonates exposed prenatally to different antiepileptic drugs /sup 13/C-AP breath test was efficiently used to prove that cytochrome AP N-demethylation was considerably stimulated. After primidone/phenobarbitone, especially in combination with phenytoin, /sup 13/C elimination reaches and even surpasses the range for older children. Valproate exposure during fetal life is not consistently followed by a significant increase in AP N-demethylation. The enzyme induction demonstrated by /sup 13/C-AP breath ...

Energy Technology Data Exchange (ETDEWEB)

A noninvasive, simplified method using inhalation of stable xenon (Xe{sup s}) and computed tomographic (CT) scanning to estimate regional cerebral blood flow (rCBF) and regional partition coefficient (r{lambda}) is described. Twenty-four patients with cerebrovascular occlusive disease and six volunteer controls inhaled 30% Xe{sup s} and 70% oxygen for 180 seconds and exhaled for 144 seconds during serial CT scanning without denitrogenation. The end-tidal Xe{sup s} concentration was continuously monitored with a thermoconductivity analyzer to determine the build-up range (A value) and build-up rate constant (K value) for arteries with the curve fitting method. The time-CT number (Hounsfield unit) curve for cerebral tissue during the Xe{sup s} washin and washout phases was used to calculate r{lambda} and rCBF using least squares curve fitting analysis. The resultant r{lambda} and rCBF map demonstrated a reliable distribution between the gray and white matter, and ...

DEFF Research Database (Denmark)

PURPOSE OF REVIEW: To review the recent literature on the prognostic value of biomarkers of liver fibrosis and impaired liver function in patients with chronic hepatitis C with or without HIV coinfection. RECENT FINDINGS: A combination of standard blood tests seems to be useful in identifying patients at risk of liver-related complications. Findings from studies investigating the validity of the Model for End-Stage Liver Disease (MELD) score in HIV-infected liver transplant candidates are conflicting. Two large studies of HIV/hepatitis C virus (HCV) coinfected patients have shown that plasma levels of the fibrosis marker hyaluronic acid are a strong predictor of clinical complications. A smaller study found hyaluronic acid and two other fibrosis tests, aspartate aminotransferase-to-platelet ratio index (APRI) and Fib-4, to be independent predictors of mortality when included in models with the MELD or the Child-Pugh-Turcotte scores. SUMMARY: Although the data are still limited, recent ...

Energy Technology Data Exchange (ETDEWEB)

The security of ports and transportation is of utmost importance for the development of economy and the security of a nation. Among the necessary actions to ensure the security of ports and borders, the inspection of containers is one of the most time consuming and expensive procedures. Potential threats are the illegal traffic of radioactive materials that could be employed for the construction of weapons, as uranium and plutonium. New techniques for the inspections of containers should be fast, allow the detection and identification of dangerous materials, and be non-invasive, to reduce costs and delays. We propose to build a large surface photon and neutron detector based on plastic scintillator to identify the presence of fissile or fertile material inside a container. The detector consists of scintillator bars, wrapped in thin foils of reflecting material containing gadolinium for neutron capture and arranged in planes separated by few-millimeter-thick lead ...

Energy Technology Data Exchange (ETDEWEB)

A crucial step in human breast cancer progression is the acquisition of invasiveness. There is a distinct lack of human cell culture models to study the transition from pre-invasive to invasive phenotype as it may occur 'spontaneously' in vivo. To delineate molecular alterations important for this transition, we isolated human breast epithelial cell lines that showed partial loss of tissue polarity in three-dimensional reconstituted-basement membrane cultures. These cells remained non-invasive; however, unlike their non-malignant counterparts, they exhibited a high propensity to acquire invasiveness through basement membrane in culture. The genomic aberrations and gene expression profiles of the cells in this model showed a high degree of similarity to primary breast tumor profiles. The xenograft tumors formed by the cell lines in three different microenvironments in nude mice displayed metaplastic phenotypes, including squamous and basal ...

Energy Technology Data Exchange (ETDEWEB)

In this study, Cu{sub 2}O/Cu composite particles were synthesized using an innovative chemical reduction method without any template and surfactant. X-ray diffraction (XRD) analysis revealed that the product mainly consisted of Cu{sub 2}O phase coexisting with a Cu phase. FE-SEM images showed that the octahedral shaped particles were Cu{sub 2}O. The electrochemical performance of the Cu{sub 2}O/Cu particles was investigated with regards to the working electrode material in alkaline solution. The particles had a maximum discharge capacity of 222.9 mAh/g at a discharge current density of 60 mA/g and a high value of 109.1 mAh/g after 50 charge-discharge cycles. Cyclic voltammetry revealed that the reaction between Cu{sub 2}O and Cu is the major electrochemical reaction during the charging and discharging process. Electrochemical impedance spectroscopy revealed that the formation of Cu{sub 2}O on the surface of Cu particles ...

British Library Electronic Table of Contents (United Kingdom)

Monthly sampling of slightly alkaline arsenic-rich stream in the Mokrsko gold deposit revealed seasonal variations in dissolved Zn, Cu, As and Mo. Concentrations of trace metal cations (Zn, Cu) increased as much as 330 and 178%, respectively, from minimum mean values at autumn to maximum mean values at spring. In contrast, concentrations of trace element oxyanions (As, Mo) revealed opposite seasonal pattern with increase to 189% (As) and 123% (Mo) during summer?autumn, indicating that in-stream biogeochemical process(es) played the main role in controlling the seasonal variations of these trace elements. The trace elements were mainly scavenged by low crystalline Mn oxyhydroxide and Fe oxyhydroxide (ferrihydrite). Results are consistent with sorption and coprecipitation processes controlli...

British Library Electronic Table of Contents (United Kingdom)

Premature Failure of a Riata Defibrillator Lead. A 63-year-old woman with a St. Jude Medical Riata 1570 right ventricular lead complained of intermittent hiccups 2 months after implant. Interrogation revealed elevated pacing threshold and diaphragmatic stimulation. Pacing and shock lead impedances remained stable. No inappropriate sensing was noted. Fluoroscopic examination of the lead revealed a thin radio-opaque wire seen between the 2 defibrillator coils away from the main body of the lead. After extraction, a tear in the insulation of the lead was noted allowing the inner wire to protrude. This case illustrates a novel mechanism of insulation failure without inappropriate sensing or impedance change.-(J Cardiovasc Electrophysiol, Vol. 22, pp. 1070-1072, September 2011)

British Library Electronic Table of Contents (United Kingdom)

This paper reports the use of molecular methods to characterize the coprophilous fungal communities (CFC) that inhabit the dung of four species of mammalian herbivores at two sites, Sevilleta National Wildlife Refuge (SNWR) in New Mexico and Wind Cave National Park (WCNP) in South Dakota. Results reveal that CFC from domesticated cattle (Bos taurus) at SNWR, and bison (Bison bison) and black-tailed prairie dogs (Cynomys ludovicianus) at WCNP were diverse but dominated primarily by members within eight taxonomic orders, including the rarely cultured and anaerobic order Neocallimastigales. In addition, 7.7% (138 of 1,788) of the sequences obtained from all dung samples were at least 97% similar to root-associated fungal (RAF) sequences previously described from blue grama (Bouteloua gracilis...

British Library Electronic Table of Contents (United Kingdom)

A concentric reducer tube, which was a part of the top exit roughing hydraulic descaler in a hot strip mill failed prematurely under working pressure. A detailed metallurgical investigation comprising physical examination, optical microscopy, scanning electron microscopy, and electron probe microanalysis was carried out to find out the genesis of the failure. Physical examination revealed cracks located symmetrically around the circumference of the tube that ran along its full length, up to the weld beads at both ends. Optical microscopy of etched samples revealed a banded ferrite-pearlite structure and the existence of forging folds near the change-in-section(160? fillets). Cracks were found to initiate from these forging folds. No structural abnormalities were found in the weld beads and...

Energy Technology Data Exchange (ETDEWEB)

The subscale Varestraint test has been used to determine the relative hot cracking susceptibility of the fusion zone in four commercial heats of alloy 800. Although all four heats were susceptible to cracking, one heat exhibited a significant increase in cracking relative to the other three. Optical metallography revealed that nearly all the cracking was localized along fusion zone grain boundaries. Microprobe analysis of the grain boundaries detected high concentrations of titanium, silicon, and niobium resulting from partitioning during solidification. The fusion zone hot cracking mechanism in alloy 800 involves the complex interaction of titanium, silicon, niobium, and carbon along the solidification boundaries. SEM and Auger analyses of the hot crack fracture surfaces revealed the presence of (Ti, Nb)-rich carbides, suggesting that these particles precipitate from the liquid which solidifies last on the fracture surface. 23 references.

Energy Technology Data Exchange (ETDEWEB)

A destructive spondyloarthropathy is reported in four patients undergoing maintenance hemodialysis for chronic renal disease. In a separate investigation a controlled, prospective radiographic study of the cervical spine revealed this spondyloarthropathy in 4 (15%) of 26 long-term dialysis patients. A single disk level was involved in three patients, and two disc levels were involved in one patient. This spondyloarthropathy correlated with the duration of dialysis but not with the radiographic evidence of renal osteodystrophy or severity of laboratory abnormalities associated with hyperparathyroidism. Three of these four patients also had discovertebral erosions or destruction involving the lumbar spine. Cervical spine flexion views revealed evidence of ligamentous laxity or instability in three (12%) dialysis patients, all with vertebral resorption and disc space narrowing. It is postulated that this instability may contribute to the ...

British Library Electronic Table of Contents (United Kingdom)

The goal of the present study was to describe the clinical, haematological and ultrasonographic findings and treatment of 17 cattle with pyelonephritis. Fifteen cattle had an abnormal general condition, which varied in severity; five animals had signs of colic. The urine was brownish-red in 11 animals and cloudy in 13. Clumps of purulent material were seen in the urine of nine animals and clots of blood in two. The specific gravity was lower than normal in 13 animals and ranged from 1.005 to 1.020. A urine test strip revealed protein in 16 animals, blood in 16 and leukocytes in 12. Bacteriological examination of urine yielded Corynebacterium renale in 11 animals, Arcanobacter pyogenes in two and Escherichia coli in one. Rectal examination revealed abnormalities of the urinary tract in 11 a...

British Library Electronic Table of Contents (United Kingdom)

In the present work, bulk amorphous and nanocrystalline Al83Fe17 alloys were obtained by consolidation of mechanically alloyed powders. Mechanical alloying of Al-17% Fe powder mixture yielded powder with an amorphous structure. Thermal behaviour of the milling product was examined using differential scanning calorimetry. This investigation revealed that the amorphous phase crystallised above 380^oC. The amorphous powder was compacted under a pressure of 7.7GPa in different conditions: at 380^oC for 600s and at 1000^oC for 180s. Structural investigations of the bulk material revealed that the amorphous structure was retained after consolidation process applied at 380^oC. Compaction under high pressure at 1000^oC caused crystallisation of the amorphous phase and appearance of metastable nano...

Energy Technology Data Exchange (ETDEWEB)

We have employed Environmental Scanning Electron Microscopy (ESEM) and Energy Dispersive X-ray (EDX) analysis to study the microstructural evolution of acrylic latex stabilised with a novel polysaccharide derived from agricultural waste. The analysis revealed that the micro structure of the latex in the 'wet' state consists of individual particles and clusters. Upon evaporation a discontinuous film is formed, with voids present within its structure, which is inconsistent with the conventional descriptions of film formation. Further ESEM examination of 'dry' specimens revealed that aging resulted in the formation of dendritic structures on the surfaces of the latex films, which EDX analysis confirmed to have been formed via crystallisation of salt. The experimental evidence suggests that the clusters, which are part of the structure of the latex, may act as nucleation centres that would allow the dendrites to ...

Energy Technology Data Exchange (ETDEWEB)

During their life, intervertebral discs undergo degenerative changes which need not necessarily become lesions. Conventional X-rays do not provide information on the condition of the intervertebral discs, so MRT or CT are recommended as primary techniques as they are non-invasive. Invasive methods like myelography and especially discography should not be used unless a case is highly problematic. In infants with pains in the back, MRT should be carried out as early as possible as there is nearly always an organic cause. (orig.) [German] Die Bandscheibe ist im Laufe des Lebens degenerativen Veraenderungen unterworfen, die klinisch zu Beschwerden fuehren koennen, aber nicht fuehren muessen. Konventionlle Roentgenaufnahmen lassen zwar die Hoehenminderung des Bandscheibenfachs und begleitende knoecherne Veraenderungen erkennen, nicht aber den Zustand der Bandscheibe selbst. Die Beurteilung der Bandscheibe und des Knochens gelingt mit der CT, die parallel zum ...

Energy Technology Data Exchange (ETDEWEB)

Noninvasive and simplified methods for estimating regional cerebral blood flow (CBF) and regional partition coefficient ({lambda}) using the inhalation of stable xenon (Xe{sup s}) and computed tomographic (CT) scanning are described. Thirty percent Xe{sup s} in 70% oxygen was inhaled for 240 seconds and exhaled for 160 seconds during serial CT scanning without denitrogenation in 26 patients with cerebrovascular diseases and four volunteer controls. During the investigation, the end-tidal Xe{sup s} concentration was continuously monitored with a thermoconductivity analyzer to determine the build-up range (A value) and build-up rate constant (K value) of the artery by the curve fitting method. Calculated A and K values were corrected by the following formulae reported previously: for patients aged 0-20 years, A{sub e} = 0.75A{sub a} + 2.15, K{sub e} = 0.67K{sub a} + 0.69; 21-40 years, A{sub e} = 0.56A{sub a} + 3.24, K{sub e} = 0.38K{sub a} + 1.12; 41-60 years, A{sub ...

UK PubMed Central (United Kingdom)

Although caloric restriction (CR) has been shown to increase lifespan in various animal models, the mechanisms underlying this phenomenon have not yet been revealed. We developed an in vitro...Full Text Available

UK PubMed Central (United Kingdom)

Spontaneous pneumothoraces are believed to arise when air from the supplying airway exit via a ruptured visceral pleural bleb into the pleural cavity. Endobronchial one-way valves (EBVs) allow air exit...Full Text Available

Science.gov (United States)

A rare, true aneurysm of a branch of the right subclavian artery is described. Transcatheter coil embolization of the feeder artery was successful in obliterating blood flow into the aneurysm and the mass reduced in size. However, the aneurysm reenlarged over the next week of follow-up due to development and enlargement of the collateral vascular network. Extirpation of the aneurysm was performed. Histopathological examination revealed a true aneurysm. PMID:11833847

Energy Technology Data Exchange (ETDEWEB)

A community health survey of 438 individuals was taken to detect health problems related to high voltage electrical transmission among an adjacent residential population. Results revealed no significant or consistent relationships between exposure to a high voltage DC power line and the perceived health problems that were measured. The sample was not, however, large enough to draw statistically significant conclusions regarding possible health effects with a very low incidence.

Energy Technology Data Exchange (ETDEWEB)

By dissolution of iron (2) carbonate in rhenium acid iron (2) perrhenate of the Fe(ReO/sub 4/)/sub 2/x4H/sub 2/O composition is obtained. By the method of thermal analysis the limits of tetra-, dihydrate and anhydrous iron (2) perrhenate stability are revealed. By means of X ray phase and IR spectroscopic analysis methods modification of structure in the process of synthesized salt dehydration is shown.

International Nuclear Information System (INIS)

The structure of the P-2, S-1 accelerator mode with one step, S-1, on double period, P-2 for systems, described by the Harper mapping as well as by standard mapping, is analyzed. Detailed analysis of stability criteria is given and comparison with the results of numerical analysis is performed. Three-period compression of the P-2, S-1 island is revealed in the standard mapping. Refs. 7, figs. 7.

International Nuclear Information System (INIS)

Structure of ferrite in drawn pearlitic steel containing 0.9 mass% C was investigated with X-ray diffraction technique using synchrotron radiation. In the detailed analysis of diffraction peaks of ferrite during the drawing process, it was experimentally revealed that the transformation of ferrite from bcc to bct due to the supersaturation of carbon in ferrite of heavily drawn pearlitic steel.

International Nuclear Information System (INIS)

The authors have used limited proteolysis of affinity-labeled estrogen receptors (ER), coupled with antireceptor antibody immunoreactivity, to assess structural features of ER and the relatedness of ER from MCF-7 human breast cancer and rat uterine cells. MCF-7 ER preparations covalently labeled with ["3H]tamoxifen aziridine (["3H]TAZ) were treated with trypsin (T), #alpha#-chymotrypsin (C), or Staphylococcus aureus V8 protease prior to electrophoresis on sodium dodecyl sulfate gels. Fluorography revealed a distinctive ladder of ER fragments containing TAZ for each protease generated from the M/sub r/ 66,000 ER. Immunoblot detection with the primate-specific antibody D75P3#gamma# revealed that all immunoreactive fragments corresponded to TAZ-labeled fragments but that some small TAZ-labeled fragments were no longer immunoreactive. In contrast, use of the antibody H222SP#gamma# revealed a correspondence between TAZ-labeled ...

CERN Document Server

We provide an analytic study of the dynamics of semiconductor lasers with injection (pump) of spin-polarized electrons, previously considered in the steady-state regime. Using complementary approaches of quasi-static and small signal analyses, we elucidate how the spin modulation in semiconductor lasers can improve performance, as compared to the conventional (spin-unpolarized) counterparts. We reveal that the spin-polarized injection can lead to an enhanced bandwidth and desirable switching properties of spin-lasers.

CERN Document Server

Gas and stars in spiral galaxies are modelled with the DUAL code, using hydrodynamic and N-body techniques. The simulations reveal morphological differences mirroring the dual morphologies seen in B and K' band observations of many spiral galaxies. In particular, the gaseous images are more flocculent with lower pitch angles than the stellar images, and the stellar arm-interarm contrast correlates with the degree of morphological decoupling.

Energy Technology Data Exchange (ETDEWEB)

High-spin states in {sup 202}Pb and {sup 203}Pb have been investigated by in-beam {gamma}-ray spectroscopy following the reaction {sup 198}Pt({sup 9}Be,xn). A search for magnetic rotational bands in these isotopes confirmed one of the two bands previously assigned to {sup 202}Pb and revealed a new band in this isotope. No evidence for magnetic rotation has been found in {sup 203}Pb. (orig.)

Energy Technology Data Exchange (ETDEWEB)

The addition of titanium to eutectic braze compositions causes these alloys to readily wet and bond to A1N ceramics. Electron microscopic characterizations of the metal-ceramic interfaces reveal the presence of TiN, along with other Ti- and Al-containing phases. The formation of such interfacial reaction products is an additional thermodynamic driving force for the creation of useful metal-ceramic bonds. 12 refs., 4 figs., 1 tab.

UK PubMed Central (United Kingdom)

Histone H3 mRNAs were found in polyA(+) fractions of total RNA prepared from alfalfa plants, calli and somatic embryos. The sequence analysis of cDNAs revealed the presence of a polyA tail on independent...Full Text Available

UK PubMed Central (United Kingdom)

After slow progress in the efforts to develop phase plates for electron microscopes, functional phase plate using thin carbon film has been reported recently. It permits collecting high-contrast images...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Several Mg-Y binary ribbons with Y content up to {approx}17.9 at.% were fabricated by melt-spinning. X-ray diffraction (XRD) revealed that the phase structure changes with increasing Y content from extended solid solution to partially amorphous, and then fully intermetallic Mg{sub 24}Y{sub 5}. Anodic potentiodynamic polarization performed in 0.01 M NaCl electrolyte (pH=12) revealed improved anodic passivity behavior compared to pure Mg for all the Mg-Y alloys. X-ray photoelectron spectroscopy (XPS) revealed that the improved passivity of Mg-Y was more related to the elemental oxidation state rather than the concentration of the surface components. To study the effect of Cl{sup -} ion on the passivity behavior, anodic potentiodynamic and potentiostatic polarization were performed on Mg-17.9 at.% Y in alkaline (pH=12) NaCl electrolytes containing Cl{sup -} ion in the concentration range from 0.00 to 0.50 M. The passive films ...

Energy Technology Data Exchange (ETDEWEB)

Plantago ovata Forsk - an economically important medicinal plant - was analyzed for trace elements and chlorophyll in a study of the effects of gamma radiation on physiological responses of the seedlings. Proton-induced X-ray emission (PIXE) technique was used to quantify trace elements in unirradiated and gamma-irradiated plants at the seedling stage. The experiments revealed radiation-induced changes in the trace element and chlorophyll concentrations.

Energy Technology Data Exchange (ETDEWEB)

Positron emission tomography (PET) and magnetic resonance imaging (MRI) studies were performed on a case of neuro-Behcet's syndrome. In accordance with the clinical signs, FDG PET (using /sup 18/F-labeled 2-F-2'-desoxyglucose) revealed disseminated storage defects in the cerebrum and cerebellum. Focal regions of enhanced signal intensity were demonstrated in the parietal white matter of the cerebrum in T2-weighted images and in the brain stem by MRI. (orig.).

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the information gathered by CONCAVE in a 1993 survey of waste generation and disposal by the oil refineries in Western Europe. The survey covered the types of waste produced, their quantities, disposal routes and costs of disposal. The results are compared with those from a 1986 survey, but because of the increased numbers of refineries reporting, comparison is difficult. The survey revealed wide variations in disposal costs depending on waste type and local circumstances.

International Nuclear Information System (INIS)

It is shown that low-frequency elastic vibrations of near-surface planar defects cause high-frequency ultrasonic radiation in surrounding air. The frequency conversion mechanism is concerned with contact nonlinearity of the defect vibrations and provides efficient generation of air-coupled higher-order ultraharmonics, ultrasubharmonics, and combination frequencies. The nonlinear air-coupled ultrasonic emission is applied for location and high-resolution imaging of damage-induced defects in a variety of solid materials.

UK PubMed Central (United Kingdom)

BackgroundThe large sensitivity, high reproducibility and essentially unlimited dynamic range of real-time PCR to measure gene expression in complex samples provides the opportunity...Full Text Available

UK PubMed Central (United Kingdom)

Recent GWAS studies focused on uncovering novel genetic loci related to AD have revealed associations with variants near CLU, CR1, PICALM and BIN1....Full Text Available

International Nuclear Information System (INIS)

We reported three cases of acute intracranial tuberculosis including miliary tuberculosis, basal meningitis, tuberculomas and neuritis of cranial nerves. All patients had native and contrast enhanced CT and MRI scans. MRI revealed more granulomas and a better imaging contrast in the detection of basal meningitis. Neuritis was diagnosed only with the MRI. MRI scans should be prefered as the imaging procedure in clinically presumed intracranial tuberculosis. (orig.).

UK PubMed Central (United Kingdom)

Mice lacking Kv1.1 Shaker-like potassium channels encoded by the Kcna1 gene exhibit severe seizures and die prematurely. The channel is widely expressed in...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Energy spectra of the Bragg reflection of the Moessbauer ..gamma..-radiation from the /sup 57/Fe/sub 3/BO/sub 6/ weakly ferromagnetic monocrystal are studied. A strong effect of the interference transitions in iron nuclei, being in non-equivalent positions, on the spectra form is revealed. The measurement results are compared with theoretical calculations.

Energy Technology Data Exchange (ETDEWEB)

The influence of MeV electrons irradiation on the gate oxide layers of hydrogenated polysilicon thin film transistors (TFTs) was investigated by measuring gate leakage currents and threshold voltages. The experimental data revealed a decrease of oxide trap density and increase of positive oxide charge. Improvement in the interface roughness and in the oxide quality near the bottom interface was observed.

UK PubMed Central (United Kingdom)

PtdIns4P is the major precursor for the synthesis of the multifunctional plasma membrane lipid, PtdIns(4,5)P₂. Yet PtdIns4P also functions...Full Text Available

International Nuclear Information System (INIS)

We have performed precision measurements in a magneto-optical trap of the 7P1/2 hyperfine structure of the isotopes 209-210Fr. The ratio of these hyperfine constants to the previously measured 7S1/2 ground state values reveals a significant hyperfine anomaly. This anomaly results from the different radial dependence of the electron density in the two atomic levels. The measurements are sensitive to changes in the radial distribution of the neutron magnetism.

UK PubMed Central (United Kingdom)

Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal degenerations caused by mutations in at least 45 genes. Using homozygosity mapping, we identified a ∼4 Mb homozygous region...Full Text Available

UK PubMed Central (United Kingdom)

We have isolated the human prointerleukin 1 (proIL-1) beta gene from leukocyte and fetal liver libraries. The nucleotide sequence and its gene organization reveals that the proIL-1 beta gene is composed...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundCotton, with a large genome, is an important crop throughout the world. A high-density genetic linkage map is the prerequisite for cotton genetics and breeding. A genetic...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The properties of Mn-doped GaAs layers grown by laser deposition were investigated with measurements of Hall effect and magneto-optical Kerr effect (MOKE). The electrical and magnetic parameters of the layers were defined by growth temperature and quantity of sputtered Mn. It was shown that room-temperature ferromagnetism is revealed by MOKE and, after ruby laser 25 ns pulse annealing, by Hall effect measurements.

UK PubMed Central (United Kingdom)

Previous studies reveal that dark-induced closure of Samanea leaflets is accompanied by H⁺ secretion from flexor motor cells. We now report that flexor tissue excised in...Full Text Available

CERN Document Server

In this paper, we extend the diversity and multiplexing tradeoff (DMT) analysis from point-to-point channels to cellular systems to evaluate the impact of inter-cell interference on the system reliability and efficiency. Fundamental tradeoff among diversity order, multiplexing gain and inter-cell interference intensity is characterized to reveal the capability of multiple antennas in cellular systems. And the detrimental effects of the inter-cell interference on the system performance of diversity and multiplexing is presented and analyzed.

Energy Technology Data Exchange (ETDEWEB)

For verification of cow fertility a /sup 3/H radioimmunoassay of progesterone in milk and blood plasma was developed. It is of high specificity and accuracy as well. Extraction of progesterone from milk was facilitated by application of alcohol. Suggested differences in milk and plasma progesterone levels between pregnant and nonpregnant cows could be revealed.

International Nuclear Information System (INIS)

Computed tomographic findings in developmental brain anomalies are more easily classified when the system used is based on embryogenesis related to morphology. Analysis of computed tomographic findings in a series of 154 patients with brain anomalies (Chiari malformation not included) revealed that specific examples of abnormalities occurring in major stages of brain development may be recognized by computed tomography. This paper deals with a group of patients with abnormalities that reflect a disturbance in neuronal migration. (orig.).

UK PubMed Central (United Kingdom)

BackgroundATRX is a tightly-regulated multifunctional protein with crucial roles in mammalian development. Mutations in the ATRX gene cause ATR-X syndrome, an X-linked...Full Text Available

UK PubMed Central (United Kingdom)

Nucleotide sequence analysis of the Escherichia coli chromosomal DNA inserted in the plasmid pLC33-5 of the Clarke and Carbon library [Clarke & Carbon (1976) Cell 9, 91-99] revealed the existence...Full Text Available

International Nuclear Information System (INIS)

In this paper a study is made of the structure and mechanical properties of the #beta# alloy system Ti-Mo-Zr-Sn (the composition of which is equivalent to the #beta# III alloy used abroad) containing different amounts of carbon. Study of the #beta#-titanium alloy containing 0.1% C revealed the presence of particles of titanium carbide. Separation of the titanium carbide promotes a reduction in impact strength, an increased tendency toward cold shortness, and poorer workability. (author).

International Nuclear Information System (INIS)

The results obtained by studying double-front extensive air showers in which more than 107 particles are contained and in which the fronts are separated by a time interval of #DELTA#t #approx# 100 ns are presented. Serious difficulties in explaining 'delayed' showers are revealed. In this connection, a hypothesis that the 'leading' showers are initiated by tachyons produced in the first interaction of primary particles is proposed.

UK PubMed Central (United Kingdom)

Surveys of the antigenic properties of a wide range of variants of the H3N2 (Hong Kong) influenza virus subtype have revealed complex patterns of variants cocirculating during each of the main epidemic...Full Text Available

CERN Document Server

We identify emission lines of post-iron peak elements in very high signal-to-noise spectra of a sample of planetary nebulae. Analysis of lines from ions of Kr and Xe reveals enhancements in most of the PNe, in agreement with the theories of s-process in AGB star. Surprisingly, we did not detect lines from Br even though s-process calculations indicate that it should be produced with Kr at detectable levels.

UK PubMed Central (United Kingdom)

Environmental and occupational exposures to heavy metals such as methylmercury (MeHg) and cadmium (Cd) pose significant health risks to humans, including neurotoxicity. The underlying mechanisms of...Full Text Available

Science.gov (United States)

Based on our cryogenic FT-IR spectroscopic studies of hydrogen bonds in cholic acid, the two-dimensional FT-IR spectroscopy was applied to enhance our understanding of the hydrogen bonds. Fine spectral structures were revealed by asynchronous 2D FT-IR spectra. The co-relationship among various bands was discussed according to the synchronous 2D FT-IR spectra. .

Energy Technology Data Exchange (ETDEWEB)

MRI provides a non-invasive diagnostic tool complementing echocardiography on one hand, and showing advantages over echocardiography, on the other hand, especially after corrective procedures. The multiple different MRI sequences need to be adapted to examinations of children and patients with congenital heart disease (CHD), and can be used to detect morphologic changes, blood-flow in the heart and thoracic vessels and diastolic or systolic function of myocardium. Several factors determine the success of the examination of a complex congenital heart disease or a postoperative situs. Pediatric radiologists and radiologists experienced in congenital heart diseases have to work in close cooperation. Echocardiography should be performed before MRI. The results of prior examinations and the clinical history of the patients, including possible palliative or reconstructive operations, must be available before MRI to guide the planning of the examination. With a systematic ...

Energy Technology Data Exchange (ETDEWEB)

Functional imaging of the pharynx used to be the domain of cineradiography, CT and ultrafast CT. The development of modern MRI techniques led to new access to functional disorders of the pharynx. The aim of this study was to implement a new MRI technique to examine oropharyngeal obstructive mechanisms in patients with obstructive sleep apnea (OSA). Sixteen patients suffering from OSA and 6 healthy volunteers were examined on a 1.5 T whole-body imager (`Vision`, Siemens, Erlangen Medical Engineering, Germany) using a circular polarized head coil. Imaging was performed with 2D flash sequences in midsagittal and axial planes. Patients and volunteers were asked to breathe normally through the nose and to simulate snoring and the Mueller maneuver during magnetic resonance imaging (MRI). Prior to MRI, all patients underwent an ear, nose and throat (ENT) examination, functional fiberoptic nasopharyngoscopy and polysomnography. A temporal resolution of 6 images/s and an in-plane resolution of ...

Science.gov (United States)

A study examined the concept of interpersonal communication competence in order to construct a more refined instrument than those currently used to measure competence. Using 70 items drawn from several existing measures of competence, 660 volunteer subjects from undergraduate communication courses at a large midwestern university provided their conception of adept and inept communicators, defined respectively as the best and worst communicators they know. Direct and multiple step-wise discriminant analyses were performed to determine the extent to which these items best discriminated between subjects' conceptions of adept and inept communicators, and to determine which of the 70 items best discriminated between these conceptions. Canonical discriminant functions revealed that the subjects clearly distinguished between adept and inept communicators. Classification results revealed that nearly 97% of the cases were classified correctly. Results ...

International Nuclear Information System (INIS)

The electronic band structure, transport properties, and lattice dynamics in AuX_2 (X = Al, Ga and In) under high pressure have been extensively studied with full potential linearized augmented plane wave and pseudopotential plane wave methods. The theoretical results for the electronic band structure and Fermi surface reveal pressure-induced electronic topological transitions (ETTs) in AuGa_2 and AuIn_2, while they are absent in AuAl_2, in excellent agreement with the experimental observations. Moreover, calculations of the transport properties at different pressures reveal subtle changes in the band structure close to the Fermi surface of the three intermetallic compounds. It is clear that the anomalies in transport properties are due to ETTs. Interestingly, a pressure-induced soft transverse acoustic (TA) phonon mode is identified only in AuGa_2. The TA phonon instability at the Brillouin zone boundary L point might be responsible for the ...

CERN Document Server

We present our discovery of a narrow-line Baldwin effect, an anti-correlation between the equivalent width (EW) of a line and the flux of the associated continuum, in 5-20$\\mu$m mid-infared lines from a sample of 68 Active Galactic Nuclei (AGN), located at z$<$0.5, observed with the Infrared Spectrograph on the {\\it Spitzer Space Telescope}. Our analysis reveals a clear anti-correlation between the EW of the [SIV] 10.51$\\mu$m, [NeII] 12.81$\\mu$m, and [NeIII] 15.56$\\mu$m lines and their mid-IR continuum luminosities, while the Baldwin effect for [NeV] 14.32$\\mu$m is not as obvious. We suggest that this anti-correlation is driven by the central AGN and not circumnuclear star formation in the host galaxy. We also find that the slope of the narrow-line Baldwin effect in the mid-infrared does not appear to steepen with increasing ionization potential. Examining the dependence of the EW to the Eddington Ratio ($L/L_{Edd}$) we find no strong relationship for ...

International Nuclear Information System (INIS)

The results of a combined investigation of splat-quenched Fe-Csub(x) (x<0.05) alloys by resistivity, X-ray diffraction and Moessbauer spectroscopy are presented. The residual resistivity increases linearly with the carbon content (#DELTA#rho=5#mu##OMEGA#cm/at.%) with a slope identical to that observed in the dilute ferritic phase. X-ray diffraction reveals the presence of a martensite structure in addition to a small fraction of residual austenite; the dependence of the a and c lattice parameters on xsub(c) agrees with earlier measurements. A detailed investigation of the relative reflexion intensities shows that the as-quenched martensites consist of a mixing of massive martensite and tetragonal martensite for low carbon content and of tetragonal martensite only for xsub(c) approximately 0.05. The Moessbauer spectra reveal 3 or 4 magnetically non equivalent iron sites. From a detailed analysis of the intensity dependence of the subspectra ...

International Nuclear Information System (INIS)

Semiconductor properties of passive films formed on the Fe-18Cr alloy in a borate buffer solution (pH = 8.4) and 0.1 M H_2SO_4 solution were examined using a photoelectrochemical spectroscopy and an electrochemical impedance spectroscopy. Photo current reveals two photo action spectra that derived from outer hydroxide and inner oxide layers. A typical n-type semiconductor behaviour is observed by both photo current and impedance for the passive films formed in the borate buffer solution. On the other hand, a negative photo current generated, the absolute value of which decreased as applied potential increased in the sulfuric acid solution. This indicates that the passive film behaves as a p-type semiconductor. However, Mott-Schottky plot revealed the typical n-type semiconductor property. It is concluded that the passive film on the Fe-18Cr alloy formed in the borate buffer solution is composed of both n-type outer hydroxide and inner oxide ...

Energy Technology Data Exchange (ETDEWEB)

In this article, the isotope geochemical study for Iceland is reviewed. Iceland is geologically unique because it is a subaerial exposure of Mid-Atlantic Ridge, which is caused by the interaction between the ridge and the Icelandic hot spot. To investigate what is happening beneath Iceland, many geochemical studies have been done. The geochemical studies using conventional Sr, Nd, Pb, He and O isotope tracers revealed the heterogeneity not only of the oceanic mantle, but also of the Icelandic hot spot mantle itself. Furthermore, the oxygen isotope studies revealed the reworking of the Icelandic crust which is altered by meteoritic water. The characterization of the Icelandic hot spot from the isotope geochemistry is very important in testing the hypothesis of the mantle-crust recycling. In near future, new tracers such as Li, B or Ce will be applied to this problem, and new constraints will be obtained. 37 refs., 7 figs.

International Nuclear Information System (INIS)

To define the prognostic factors after surgical resection and evaluate the effectiveness of Post Operative Radiotherapy (PORT) in cases with cholangiocarcinoma, 44 cases with proximal cholangiocarcinoma were examined. The mean observation period was 20.6 months, and the survival rates 1, 3 and 5 years after the resection were 79.9%, 59.8% and 39.3%, respectively. Univariate analysis revealed that the presence of lymph node metastasis and absence of PORT were significant poor prognostic factors. Multivariate analysis revealed that the absence of PORT was a significant poor prognostic factor. The survival rates for 1 and 3 years after the resection were 80.0% and 40.0% in the curable A/B and PORT (-) group, and 100% and 53.3% in curable C and PORT (+) group. There were no local reccurences in the pathologically classified hm2 and em2 patients who underwent PORT. Even when the surgical margin is positive for the carcinoma pathologically, it is ...

International Nuclear Information System (INIS)

This study aimed to reveal that severe disturbance of attachment relationship with primary care-giver can affect functional and anatomical brain development by measuring cerebral perfusion on "9"9"mTc-ECD brain SPECT and correlative MRI. We included 18 children aged 31 to 76 months who met the diagnostic criteria of RAD as defined in DSM-IV and ICD-10 and SSP and CARS. "9"9"mTc-ECD SPECT was performed using CERASPECT. MRI was performed in all patients. SPECT data were visually assessed. 15 of 18 children had abnormal perfusion on SPECT, revealing decreased perfusion of Lt.thalamus (7/15) and Rt.thalamus (3/15), and bilateral thalami (5/15). Perfusion of basal ganglia was decreased in 8 children. Decreased perfusion of Lt. parietal area was seen in 2. Whereas, all patients had normal MR findings. Perfusion abnormalities involving thalamus, BG in most children with RAD were found in this study. These results suggest that brain development of ...

Energy Technology Data Exchange (ETDEWEB)

Tests with a 61 cm diameter fluidized-bed combustor revealed that raw cotton gin trash could be efficiently burned while satisfying Federal standards for particulate emissions. Certain chemicals within cotton gin trash zone can cause slagging or caking of ash and bed particles in the combustion zone. They can also corrode and accumulate on the heat recovery equipment. These problems are not considered insurmountable and methods of control are being studied. Raw cotton gin trash was also converted into a low Btu gas using fluidized-bed technology. Tests with a 30 cm diameter gasifier revealed that raw gin trash could be converted to a combustible gas, containing carbon monoxide and hydrogen. The heating value of the gas ranged from 3.65 to 5.29 MJ/m3 and about 50 percent of the heat value of the raw trash was converted to combustible gases. Economic analyses have shown that these techniques can be economically competitive with present fuels in ...

Energy Technology Data Exchange (ETDEWEB)

The microstructure of the secondary deformation zone (SDZ) near the cutting surface in metal chips of Ti-6Al-4V formed during machining was investigated using focused ion beam (FIB) specimen preparation and transmission electron microscopy (TEM) imaging. Use of the FIB allowed precise extraction of the specimen across this region to reveal its inhomogeneous microstructure resulting from the non-uniform distribution of strain, strain rate, and temperature generated during the cutting process. Initial imaging from conventional TEM foil preparation revealed microstructures ranging from heavily textured to regions of fine grains. Using FIB preparation, the transverse microstructure could be interpreted as fine grains near the cutting surface which transitioned to coarse grains toward the free surface. At the cutting surface a 10 nm thick recrystallized layer was observed capping a 20 nm thick amorphous layer.

Science.gov (United States)

The goal of the present study is to elucidate the effect of lipid domain formation on activities of Naja naja atra and Bungarus multicinctus phospholipase A(2) (PLA(2)) enzymes. Sphingomyelin inhibited enzymatic activity and membrane-damaging activity of PLA(2) against egg yolk phosphatidylcholine (EYPC), while cholesterol and cholesterol sulfate abrogated the inhibitory effect of sphingomyelin. The ability of cholesterol and cholesterol sulfate to abolish the inhibitory effect of sphingomyelin was closely related to their capacity to induce domain formation in EYPC/sphingomyelin vesicles. Laurdan fluorescence measurement revealed that membrane packing of EYPC/sphingomyelin vesicles was differently affected by cholesterol and cholesterol sulfate. Unlike cholesterol, cholesterol sulfate was unable to promote domain formation in dipalmitoylphosphatidylcholine (DPPC) vesicles. Cholesterol increased but cholesterol sulfate reduced PLA(2) activity against DPPC. ...

International Nuclear Information System (INIS)

Gel filtration of human erythrocyte (RBC) lysate incubated with labeled thyroxine (Tu) or triiodothyronine (Tt) revealed co-elution of a major iodothyronine-binding fraction (R-2) and hemoglobin. Solutions of purified human hemoglobin and Tt also showed co-elution of hormone and hemoglobin. Because hematin and protoporphyrin were shown to bind labeled Tt, the oxygen-binding site on hemoglobin was excluded as the site of iodothyronine-hemoglobin interaction. Analysis of hormone binding by heme and globin moieties showed Tt binding to be limited to the heme fraction. Addition of excess unlabeled Tt to hemoglobin or heme incubated with labeled Tt indicated 75% to 90% of hormone binding was poorly dissociable. These observations suggested that the presence of hemoglobin in RBC lysate or in serum could influence the measurement of Tu and Tt by specific radioimmunoassay (RIA). Subsequent studies of the addition to serum of human hemoglobin revealed a ...

Energy Technology Data Exchange (ETDEWEB)

Nine coals from Spanish, British, German and American mining basins were hydrogenated using Fe catalyst precursors (red mud and FeSO{sub 4}), without solvent at 300, 350, and 400 {degree}C and 10 MPa of H{sub 2}. Overall conversion and product distribution are related to the textural characteristics of the original coals and are studies throughout the distinct hydrogenation processes. Results reveal that with FeSO{sub 4} as a catalyst precursor, conversions increase with coal surface area. However, when red mud (RM) is used, conversions are independent of coal textural characteristics. Higher conversions are obtained with FeSO{sub 4} than with RM at 300 and 350 {degree}C whereas at 400 {degree}C higher conversions are obtained with RM. This different catalytic activity is also reflected in the changes of the textural characteristics observed in each case. Up to 350 {degree}C, the residues from FeSO{sub 4}-catalyzed processes reveal increased ...

Science.gov (United States)

Symplastic transport occurs between neighbouring plant cells through functionally and structurally dynamic channels called plasmodesmata (PD). Relatively little is known about the composition of PD or the mechanisms that facilitate molecular transport into neighbouring cells. While transmission electron microscopy (TEM) provides 2-dimensional information about the structural components of PD, 3-dimensional information is difficult to extract from ultrathin sections. This study has exploited high-resolution scanning electron microscopy (HRSEM) to reveal the 3-dimensional morphology of PD in the cell walls of algae, ferns and higher plants. Varied patterns of PD were observed in the walls, ranging from uniformly distributed individual PD to discrete clusters. Occasionally the thick walls of the giant alga Chara were fractured, revealing the surface morphology of PD within. External structures such as spokes, spirals and mesh were observed ...

Science.gov (United States)

Metabolic engineering of photosynthetic organisms is required for utilization of light energy and for reducing carbon emissions.Control of transcriptional regulators is a powerful approach for changing cellular dynamics, because a set of genes is concomitantly regulated. Here, we show that overexpression of a group 2 ? factor, SigE, enhances the expressions of sugar catabolic genes in the unicellular cyanobacterium, Synechocystis sp. PCC 6803. Transcriptome analysis revealed that genes for the oxidative pentose phosphate pathway and glycogen catabolism are induced by overproduction of SigE. Immunoblotting showed that protein levels of sugar catabolic enzymes, such as glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, glycogen phosphorylase, and isoamylase, are increased. Glycogen levels are reduced in the SigE-overexpressing strain grown under light. Metabolome analysis revealed that metabolite levels of the TCA cycle and ...

International Nuclear Information System (INIS)

The nature of the electrolyte strongly influences the electrode kinetics of the oxygen evolution reaction (OER) and electrochemical ozone production (EOP) mainly by affecting the degree of coverage by the intermediates of both processes. The anomalous behaviour of the Tafel coefficient, b, as a function of temperature was attributed to surface adsorption of the electrolyte species, and the competition between them, as well as gas bubble adherence. Comparison of the current efficiencies of the EOP, PHI_E_O_P, determined for different temperatures and supporting electrolyte compositions, showed the presence of fluorinated anions increases PHI_E_O_P. The influence of the anion nature on PHI_E_O_P, when analysed in the light of the proposed electrode mechanism, reveals introduction into the electrolyte of anions having a high electronegativity changes the double layer structure resulting in an increase of surface concentration of the active centres leading to EOP. The ...