2,340 research outputs found
A Comment on the Model Act
A Model Act for the Protection of Rights of Prisoners (Model Act) attempts to enroll the courts in more vigorous efforts to improve the treatment of inmates, to encourage inmates by broadening access to the courts for redress of grievances, and to provide the courts with a more precise measure of permissible and non-permissible treatment of inmates. It is doubtful that a model act is the best vehicle for accomplishing any of these goals. A model act that does not address itself to the agency that has the authority to carry it out and that fails to require that agency’s conformance, under pain of penalty, is too passive and therefore doomed to failure
Review of “Sentencing: The Decision as to Type, Length, and Conditions of Sentence,” By Robert O. Dawson
Deep Drilling in the Highly Laminated Pinedale Anticline: Downhole Vibrations Study and Bit Dysfunction Diagnosis
Ultra Petroleum has been drilling in the Pinedale Anticline in Wyoming since 2003. At that point in time, wells could take as much as 75 days to reach target depth. In the first quarter of 2015, Ultra Petroleum, has greatly reduced their spud to target depth time to 9 days. However, despite their drastic improvement in performance over the years, Ultra’s current performance has seemed to have plateaued due to consistently occurring non-productive time on each well resulting from as many as three bit trips to replace damaged drill bits, while drilling the 6 inch production hole. Hours spent tripping in and out of the hole to replace worn drill bits is extremely costly. In the third quarter of 2014, Ultra in an effort to improve performance, began a concerted effort to target this problem area and improve performance. After training Ultra Petroleum personnel on a physics-based, continuous improvement set of practices, Ultra Petroleum’s performance increased significantly. In addition to the training, Ultra Petroleum and Texas A&M University examined their operations performance and practices using downhole drilling dynamics data. After the analysis, suggestions were made for engineering redesign possibilities. The objective of this study is to determine the in-situ dynamics state of the bottom hole assembly and drill bit, and how this excited vibrational state contributes to the bit damage seen from the drill bits pulled out of the well. This thesis will document that students work and findings. In order to accomplish this goal downhole dynamics measurements were studied to determine the specific vibrations present in the drilling of these wells. In addition these measurements were used to determining the severity of each vibration type and the effectiveness of specific drilling equipment at mitigating their negative effects on performance and tool life. Meaningful results were obtained from the downhole dynamics measurements that provide both knowledge to the operator and suggestions for ways to improve performance and tool life, and include conclusions regarding the effectiveness of roller reamers and depth of cut control bits in reducing torsional oscillation, the effectiveness of full-gauge stabilization and extended gauge bits at reducing lateral vibrations, and hypotheses about the effectiveness of incorporating some specific tools and techniques for performance improvement
The Diagnosis of Dyspepsia in General Practice with Notes on a Simple Method of Classification
In the Introduction we defined dyspepsia so as to include all cases, functional or organic, in which discomfort of any kind occurred during digestion; and we stated our object as follows: (1) To formulate a routine procedure, suitable for General Practice, in the examination and diagnosis of cases of dyspepsia. (2) To classify the various kinds of dyspepsia in a way which shall be useful and simple; and which shall describe each condition adequately for the purpose of rational treatment. (5) To examine the results in 170 cases. In Chapter Three we have explained our procedure. This is more or less in accordance with convention as regards the history, interrogation and examination, i.e. the purely clinical part. That part must be done as fully in General Practice as in hospital work and in it there is no curtailment desirable or justifiable. It is in regard to Special Methods (more particularly the test-meal, the test for occult blood in the stools and the use of X-rays) that we have endeavoured to discriminate and decide in which forms of dyspepsia one or more of these is necessary. The conclusions reached are referred to in detail under the sections on the various diseases. We have made a classification of dyspepsia which seems to us to fulfil the purpose we have indicated above. The difficulties have been discussed and reasons advanced for the arrangement we have formulated in Chapter Four. In the second Volume notes of 170 cases have been included. A few conclusions and comments regarding these are given at the end of the Volume. The case-sheets are constructed on the lines indicated in our routine procedure. It is not to be supposed that these notes contain all that was used in the diagnosis. They contain the salient features and, we trust, make clear the method by which we investigate a suspected case of dyspepsia. Much that is important has of necessity been excluded on account of exigencies of space. For example, the examiner's impression of the patient's temperament has often been summed up by such a word as "nervous." To deal adequately with questions of this nature is impossible in tabular notes such as we have been obliged to use. It is apparent however that they may be of considerable importance in the diagnosis
Deep Drilling in the Highly Laminated Pinedale Anticline: Downhole Vibrations Study and Bit Dysfunction Diagnosis
Ultra Petroleum has been drilling in the Pinedale Anticline in Wyoming since 2003. At that point in time, wells could take as much as 75 days to reach target depth. In the first quarter of 2015, Ultra Petroleum, has greatly reduced their spud to target depth time to 9 days. However, despite their drastic improvement in performance over the years, Ultra’s current performance has seemed to have plateaued due to consistently occurring non-productive time on each well resulting from as many as three bit trips to replace damaged drill bits, while drilling the 6 inch production hole. Hours spent tripping in and out of the hole to replace worn drill bits is extremely costly. In the third quarter of 2014, Ultra in an effort to improve performance, began a concerted effort to target this problem area and improve performance. After training Ultra Petroleum personnel on a physics-based, continuous improvement set of practices, Ultra Petroleum’s performance increased significantly. In addition to the training, Ultra Petroleum and Texas A&M University examined their operations performance and practices using downhole drilling dynamics data. After the analysis, suggestions were made for engineering redesign possibilities. The objective of this study is to determine the in-situ dynamics state of the bottom hole assembly and drill bit, and how this excited vibrational state contributes to the bit damage seen from the drill bits pulled out of the well. This thesis will document that students work and findings. In order to accomplish this goal downhole dynamics measurements were studied to determine the specific vibrations present in the drilling of these wells. In addition these measurements were used to determining the severity of each vibration type and the effectiveness of specific drilling equipment at mitigating their negative effects on performance and tool life. Meaningful results were obtained from the downhole dynamics measurements that provide both knowledge to the operator and suggestions for ways to improve performance and tool life, and include conclusions regarding the effectiveness of roller reamers and depth of cut control bits in reducing torsional oscillation, the effectiveness of full-gauge stabilization and extended gauge bits at reducing lateral vibrations, and hypotheses about the effectiveness of incorporating some specific tools and techniques for performance improvement
Multiscale Finite Element Modeling of Active Contraction in Striated Muscle
Greater than one in three American adults have at least one type of cardiovascular disease, a major cause of morbidity. Computational cardiac mechanics has become an important part of the research effort to understand the heart’s response to mechanical stimuli and as an extension, disease progression and potential therapies. To this end, the present work aims to extend these efforts by implementing a cell level contractile model in which active stress generation in muscle tissue is driven by half-sarcomere mechanics. This is accomplished by enhancing the MyoSim model of actin and myosin in order to produce a multiscale model. This contraction model simulates cross-bridge dynamics and captures key components of contraction such as length-dependent activation, Ca2+ activation and sensitivity, and filament cooperativity. Embedding this physiologically motivated contraction model allows for the testing of hypotheses and predictions regarding the interplay between molecular mechanisms and organ level function, while capturing spatial heterogeneity. This multiscale approach has been used to predict an increase in the end-systolic pressure-volume relationship due to the inclusion of a recently discovered super-relaxed state in left-ventricle simulations. It has also been used to predict a decrease in stress generation and efficiency in skeletal muscles due to myofibril misalignment. Finally, the foundation for cardiac growth and remodeling simulations has been implemented
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Interactions of halogens with amines
The individual stages of the interaction of amines with halogens - in particular, iodine - have been studied. 'In the course of this investigation, it has been shown that amines and iodine interact initially via the nitrogen lone pair to form molecular complexes (CHARGE-TRANSFER COMPLEXES). Several of these have been isolated and some of their properties studied in detail. It was thus determined that these complexes can undergo further chemical change during which the hydrogen iodide which is generated converts any unreacted amine to the corresponding hydroiodide salt. The latter is inert to oxidation by iodine under the conditions employed. It has been shown that this mode of reaction is dependent upon the availability of a-aliphatic hydrogen in the amine molecule.
The initial oxidation product derived from the amine is the corresponding IMMONIUM SALT. This intermediate may, according to reaction conditions, undergo hydrolysis to secondary amine and carbonyl compound or conversion to ENAMINE; the latter may then undergo further transformation by inter- or intramolecular reaction.
The nature of the products isolated from the oxidation of several amines by iodine in isopropanol solution has been rationalised in terms of this generalised reaction pathway, which is analogous to those proposed by other workers for the oxidation of amines by other two-electron oxidants.
This reaction pathway also applies to the formation of an industrial disinfectant by the action of solid iodine on a commercially available tertiary amine mixture. It was thus demonstrated that most of the amine used is recovered from the reaction mixture as the base hydroiodide and that the hydrogen iodide needed for this conversion is formed during the degradative oxidation of a minor proportion of the starting material.
Furthermore, it has been established that the biocidal principle of the commercial disinfectant formulation is the N-alkyldiethanolamine hydriodide. A concurrent study of the effect of structure on biological activity has confirmed the dependence of disinfectant activity on detergent properties in this class of disinfectants
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