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We observed ionization of Xe atoms creating ionic state of up to Xe^6+ by a 1-nsec CO_2 laser pulse at 10.6 μm. The results implied stepwise ionization.

We present a simple technique to measure the absorption coefficient of molecules which avoids the interference of the distortion of the spatial profile of the laser beam due to self-focusing/self-defocusing.

Thirty nulliparous patients with a Bishop score of 4 or less had labour induced with prostaglandin E, in triacetin gel, initial dose 2 mg, with Further doses of 1 or 2 mg at 6 and 12 h if required. Seventeen of 27 patients (63 per cent) were in established labour and required no further stimulation by 18 h. The mean induction to delivery interval was 13 h. Eight more patients proceeded to vaginal delivery with the aid of oxytocin stimulation, with a mean induction to delivery interval of 38·5 h. Thus 93 per cent achieved vaginal delivery. Patients not responding to a total dose of 4 mg are unlikely to have successful induction with further doses of prostaglandin E, gel.

Using intense mode-locked CO2 laser pulse trains we verified the occurrence of the laser-induced, new-type dynamic optical tunneling of electrons from a gold surface. The results are in accordance with the theoretical predictions and our previous experiments carried out for both atoms and gold surface using single longer (ns) CO2 laser pulses. Unknown properties of the development of the CO2 laser train are revealed based on our higher-order coherence detection of electron emission.

In recent years, FRP composite wrap repair is the most preferable pipeline rehabilitation system used in the pipeline industry. However, some issues concerning this repair method are not fully understood by the industry. Effect of defect geometries toward the efficiency of composite repaired pipe is one of the issues that concerned by the industry. Pipeline repair design codes and standards have been developed mainly focus on the defect depth and neglect other defect geometries such as defect length and defect width. Previous studies stated that defect geometries especially defect width should not be ignored in evaluating and designing pipe repair system. Therefore, the burst pressure of the composite repaired pipeline subjected to various defect widths was determined through this study in order to evaluate the effect of defect width upon the burst capacity of composite repaired pipeline. Finite element analysis was used to determine the burst capacity of the composite repaired pipe with rectangular shape of defect. There are three different widths were selected with constant defect length and depth. The base model of composite repaired pipe was developed and validated and then modified with the various defect widths in this study. The result shows that burst pressure for three different models vary with a percentage of 12.51% between the maximum burst pressure and minimum burst pressure. The stress contour plot extracted from the finite element analysis revealed that the area of highest stress (557.7MPa) is located around defect region. As the defect is getting wider and subsequently creating a bigger defect area, stress concentration is also getting larger at the defect region. With this, the composite repaired pipe tends to fail at lower pressure when the defect getting wider. Based on the results, the defect width is proven to affect the burst capacity of composite repaired pipe.

The variable gradient method was used to generate a Lyapunov function for the system of first-order differential equations describing the synchronous machine, and Fallside and Patel (1966) used this V-function to estimate the domain of stability of the system.This particular problem, as mentioned by Barbashin (1961), was solved by Yanko-Trinitsky (1958). Trinitsky, according to Barbashin, used the ' separation of variables ' method to generate his V-function, and in his analysis, he included second-order terms, which is more general than the problem solved by Fallside and Patel (1966).

This paper contains the study performed on the behavior of double-web angles by using finite element analysis computer package known as "Abaqus". The aim of this present study was simulating the behavior of double-web angles (DWA) steel connections. The purpose of this article is to provide the basis for the fastest and most economical design and analysis and to ensure the required steel connection strength. This study, started used review method of behavior of steel beam-to-column bolted connections. Two models of different cross-section were examined under the effect of concentrated load and different boundary conditions. In all the studied case, material nonlinearity was accounted. A sample study on DWA connections was carried out using both material and geometric nonlinearities. This object will be of great value to anyone who wants to better understand the behavior of the steel beam to column connection. The results of the study have a field of reference for future research for members of the development of the steel connection approach with simulation model design.

Concerns regarding the negative impact towards environment due to the increasing use of natural sand in construction industry and dumping of industrial solid wastes namely coal bottom ash (CBA) and oil palm shell (OPS) has resulted in the development of environmental friendly lightweight concrete. The present study investigates the effect of coal bottom ash as partial fine aggregate replacement towards workability and compressive strength of oil palm shell lightweight aggregate concrete (OPS LWAC). The fresh and mechanical properties of this concrete containing various percentage of coal bottom ash as partial fine aggregate replacement were investigated. The result was compared to OPS LWAC with 100 % sand as a control specimen. The concrete workability investigated by conducting slump test. All specimens were cast in form of cubes and water cured until the testing age. The compressive strength test was carried out at 7 and 28 days. The finding shows that integration of coal bottom ash at suitable proportion enhances the strength of oil palm shell lightweight aggregate concrete.

The global demand of 2-ethylhexyl acrylate (2EHA) market has witnessed a significant growth in the past few years and this growth is anticipated to increase in the coming years. 2EHA is one of the basic organic building blocks that mainly used in the production of coatings, adhesives, superabsorbents, thickeners and plastic additives. Homogenous acid-catalysed esterification of acrylic acid (AA) with 2-ethylhexanol (2EH) is commonly used for the production of 2EHA. The homogeneous catalysts such as sulfuric and para-toluene sulfonic acid have resulted the costly and complicated downstream process that generates acidic, corrosive and non-environmental friendly waste. Therefore, it is importance to develop a cheaper process that employing heterogeneous catalysts and alternative raw material from wastewater containing acrylic acid. In this research, the study for the esterification of AA with 2EH catalysed by ion-exchange resin was conducted. The best sulfonic acid functional cation-exchange resin among SK104, SK1B, PK208, PK216, PK228, RCP145, and RCP160 was screened. PK208 outperformed the other resins and it was used subsequently in the parametric studies. The effect of important parameters (initial concentration of acrylic acid (AA), temperature, molar ratio of reactant (AA and 2EH), catalyst loading, and polymerisation inhibitor loading) was studied using 2 factorial design to determine the significant parameters to the esterification. It was found that the initial concentration of AA and temperature were most significantly affecting the esterification of AA with 2EH.

A selective absorption cross section of 100:1 was measured for Freon 123-d and natural Freon 123 at the 10.2- and 10.6-μm lines of a TEA CO_2 laser. Multiple-photon absorption occurs at low fluence (0.1 J/cm^2) at 10.2 μm but not at 10.6 μm.

We observed ionization of Xe atoms creating ionic state of up to Xe^6+ by a 1-nsec CO_2 laser pulse at 10.6 µm. Theresults implied stepwise ionization.

A train of 150-fs 76-MHz pulses is directed into a Michelson interferometer with a path difference larger than the pulse spatial length. A modulated spectrum with a modulation frequency that increases with the path difference is observed. The consequence is discussed.

A 100-MW double-discharged TEA-CO2laser was used to induce the polymerization of ethylene gas at pressures ranging from 250 to 900 psi at room temperature. The polymerization product was mainly tetradecane (CH3(CH2)12CH3) (∼80%) and octadecane (CH3(CH2)16CH3) (∼20%).

The determination of a high-power CO_2 laser beam spot size is described. The method consists of measuring burn pattern radii in holographic emulsion as a function of laser pulse energy.

Neural networks have been used to successfully solve the inverse problem of determining the source location based on field or coherence measurements. The conditions and types of neural networks that are effective in solving this problem are discussed. Neural network topology will be considered, as well as the source‐array geometry and its effect on performance. Simulation results will be provided, which demonstrate under what conditions interpolation is possible. Finally, a discussion of other source localization algorithms will be given. These methods will be contrasted to the neural network methodology.

Nasal mites (Rhinophagussp.) were found within the mucosal and submucosal nasal tissues and bone marrow of the upper skull in two of five adult baboons (Papiosp.).

The worldwide demand for a Tire Pressure Monitoring System (TPMS) has grown due to the dangers posed by widespread tire safety abuse. The National Highway Traffic Safety Administration (NHTSA) estimates that 23,000 accidents and 535 fatalities per year involves flat tires or blowout both of which can be the result of improperly inflated tires. To further enhance vehicular safety, US government and Europe mandated the use of TPMS for all passenger cars by year 2008 and 2012 respectively. This prepare illustrates the packaging of a low cost yet complex TPMS device that involves MEMS (pressure sensing and accelerometer devices) and Controller chips integrated as one in a low cost Pre-molded Leadframe Cavity Package. Advanced solutions to resolve process challenges and material difficulties have paved the way to successfully qualify the product meeting all the intensive automotive requirements.

Kerr effect accounts for the change in refractive index of a material with the light intensity and appears in all known optical materials. In this work we analyze Kerr effect in structured superluminal media (e.g some specific types of resonators). We show that Kerr effect in these structures can be cancelled or even reversed (in comparison with the Kerr effect of the material composing the structure) depending on the group index of the structure. We also discuss some possible realizations of structured superluminal media.

Mutation testing of the cystic fibrosis transmembrane conductance regulator (CFTR) gene is often required for a definitive diagnosis of cystic fibrosis, but >1000 mutations are known.

A working group supported by the Office of Rare Diseases of the National Institutes of Health formulated neuropathologic criteria for corticobasal degeneration (CBD) that were subsequently validated by an independent group of neuropathologists. The criteria do not require a specific clinical phenotype, since CBD can have diverse clinical presentations, such as progressive asymmetrical rigidity and apraxia, progressive aphasia, or frontal lobe dementia. Cortical atrophy, ballooned neurons, and degeneration of the substantia nigra have been emphasized in previous descriptions and are present in CBD, but the present criteria emphasize tau-immunoreactive lesions in neurons, glia, and cell processes in the neuropathologic diagnosis of CBD. The minimal pathologic features for CBD are cortical and striatal tau-positive neuronal and glial lesions, especially astrocytic plaques and thread-like lesions in both white matter and gray matter, along with neuronal loss in focal cortical regions and in the substantia nigra. The methods required to make this diagnosis include histologic stains to assess neuronal loss, spongiosis and ballooned neurons, and a method to detect tau-positive neuronal and glial lesions. Use of either the Gallyas silver staining method or immunostains with sensitive tau antibodies is acceptable. In cases where ballooned neurons are sparse or difficult to detect, immunostaining for phospho-neurofilament or α-B-crystallin may prove helpful. Methods to assess Alzheimer-type pathology and Lewy body pathology are necessary to rule out other causes of dementia and Parkinsonism. Using these criteria provides good differentiation of CBD from other tauopathies, except frontotemporal dementia and Parkinsonism linked to chromosome 17, where additional clinical or molecular genetic information is required to make an accurate diagnosis.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

We report a pathologically proven case of Creutzfeldt-Jakob disease (CJD) with striking asymmetry in abnormal high signal intensity of the basal ganglia on long-repetition-time MRI. Symmetric or asymmetric high signal intensity of the basal ganglia, in the appropriate clinical setting, may be a specific finding of CJD.