Development of a fast response neutron detector for the supersonic FRC collision process

The collisional merging experiments of the field-reversing configuration (FRC) at supersonic/Alfvénic velocities have been performed in the FRC Amplification via Translation-Collisional Merging device only in Japan. This experiment may excite shockwaves and cause particle acceleration. To obtain supporting evidence of particle acceleration by shockwaves, we have proposed to observe neutrons originating from the D-D fusion reaction of accelerated non-thermal particles. A plastic scintillation detector has been developed for the supersonic/Alfvénic collision/merging FRC experiment. The developed neutron detector has sufficient performance of neutron sensitivity and nanosecond response time. In the collisional merging process, we obtained a signal that could be considered a neutron, which is not predicted by the adiabatic compression process in the two-dimensional magnetohydrodynamics simulation.

Magnetic diagnostic suite of the C-2W field-reversed configuration experiment

A fundamental component of any magnetically confined fusion experiment is a firm understanding of the magnetic field. The increased complexity of the C-2W machine warrants an equally enhanced diagnostic capability. C-2W is outfitted with over 700 magnetic field probes of various types. They are both internal and external to the vacuum vessel. Inside, a linear array of innovative in-vacuum annular flux loop/B-dot combination probes provide information about plasma shape, size, pressure, energy, temperature, and trapped flux when coupled with established theoretical interpretations. A linear array of B-dot probes complement the azimuthally averaged measurements. A Mirnov array of 64 3D probes, with both low and high frequency resolution, detail plasma motion and MHD modal content via singular value decomposition analysis. Internal Rogowski probes measure axial currents flowing in the plasma jet. Outside, every feed-through for an internal probe has an external axial field probe. There are many external loops that measure the plasma formation dynamics and the total external magnetic flux. The external measurements are primarily used to characterize eddy currents in the vessel during a plasma shot. Details of these probes and the data derived from their signals are described.

A mass resolved, high resolution neutral particle analyzer for C-2U

C-2U is a high-confinement, advanced beam driven field-reversed configuration plasma experiment which sustains the configuration for >5 ms, in excess of typical MHD and fast particle instability times, as well as fast particle slowing down times. Fast particle dynamics are critical to C-2U performance and several diagnostics have been deployed to characterize the fast particle population, including neutron and proton detectors. To increase our understanding of fast particle behavior and supplement existing diagnostics, an E ∥ B neutral particle analyzer was installed, which simultaneously measures H⁰ and D⁰ flux with large dynamic range and high energy resolution. Here we report the commissioning of the E ∥ B analyzer, confirm the instrument has energy resolution ΔE/E≲0.1 and a dynamic range E_max/E_min∼30, and present measurements of initial testing on C-2U.

Search for gravitational waves associated with γ-ray bursts detected by the interplanetary network

We present the results of a search for gravitational waves associated with 223 γ-ray bursts (GRBs) detected by the InterPlanetary Network (IPN) in 2005-2010 during LIGO's fifth and sixth science runs and Virgo's first, second, and third science runs. The IPN satellites provide accurate times of the bursts and sky localizations that vary significantly from degree scale to hundreds of square degrees. We search for both a well-modeled binary coalescence signal, the favored progenitor model for short GRBs, and for generic, unmodeled gravitational wave bursts. Both searches use the event time and sky localization to improve the gravitational wave search sensitivity as compared to corresponding all-time, all-sky searches. We find no evidence of a gravitational wave signal associated with any of the IPN GRBs in the sample, nor do we find evidence for a population of weak gravitational wave signals associated with the GRBs. For all IPN-detected GRBs, for which a sufficient duration of quality gravitational wave data are available, we place lower bounds on the distance to the source in accordance with an optimistic assumption of gravitational wave emission energy of 10(-2)M⊙c(2) at 150 Hz, and find a median of 13 Mpc. For the 27 short-hard GRBs we place 90% confidence exclusion distances to two source models: a binary neutron star coalescence, with a median distance of 12 Mpc, or the coalescence of a neutron star and black hole, with a median distance of 22 Mpc. Finally, we combine this search with previously published results to provide a population statement for GRB searches in first-generation LIGO and Virgo gravitational wave detectors and a resulting examination of prospects for the advanced gravitational wave detectors.

Search for gravitational waves associated with γ-ray bursts detected by the interplanetary network

We present the results of a search for gravitational waves associated with 223 γ-ray bursts (GRBs) detected by the InterPlanetary Network (IPN) in 2005-2010 during LIGO's fifth and sixth science runs and Virgo's first, second, and third science runs. The IPN satellites provide accurate times of the bursts and sky localizations that vary significantly from degree scale to hundreds of square degrees. We search for both a well-modeled binary coalescence signal, the favored progenitor model for short GRBs, and for generic, unmodeled gravitational wave bursts. Both searches use the event time and sky localization to improve the gravitational wave search sensitivity as compared to corresponding all-time, all-sky searches. We find no evidence of a gravitational wave signal associated with any of the IPN GRBs in the sample, nor do we find evidence for a population of weak gravitational wave signals associated with the GRBs. For all IPN-detected GRBs, for which a sufficient duration of quality gravitational wave data are available, we place lower bounds on the distance to the source in accordance with an optimistic assumption of gravitational wave emission energy of 10(-2)M⊙c(2) at 150 Hz, and find a median of 13 Mpc. For the 27 short-hard GRBs we place 90% confidence exclusion distances to two source models: a binary neutron star coalescence, with a median distance of 12 Mpc, or the coalescence of a neutron star and black hole, with a median distance of 22 Mpc. Finally, we combine this search with previously published results to provide a population statement for GRB searches in first-generation LIGO and Virgo gravitational wave detectors and a resulting examination of prospects for the advanced gravitational wave detectors.

Growth and risk factors for expansion of dilated popliteal arteries

OBJECTIVES

The aims of this study were to investigate the change in maximum diameter of ectatic popliteal arteries during ultrasound surveillance and assess clinical predictors of their expansion.

METHODS

Over a ten year period 67 patients with ectasia affecting one (n = 1) or both (n = 66) popliteal arteries entered this surveillance study. Patients were followed for a median of 3.1 years, at a median scan interval of 7.6 months.

RESULTS

Growth of ectatic popliteal arteries was typically slow (<1 mm/yr). Initial artery diameter at entry to the study was not found to be predictive of subsequent growth. Seven patients followed for a median of 2 years had an expansion in popliteal artery diameter to >or=20 mm during follow-up. All of these patients had undergone aneurysm repairs at other arterial sites and none of them had diabetes. These participants also had a significantly higher rate of previous intervention of the contralateral popliteal artery in comparison to those that did not reach the 20 mm threshold (p < 0.001). Growth profiles of arteries that underwent significant expansion during surveillance were frequently characterised by a staccato pattern.

CONCLUSIONS

Expansion of ectatic popliteal arteries is typically slow but difficult to predict. Trends observed in this study suggest that patients with extra-popliteal aneurysms, patients with previously treated contralateral popliteal artery ectasia and those who are not diabetics may be more prone to significant expansion. Further studies are required to validate these potential growth predictors.

Magnetoencephalography for pediatric epilepsy: how we do it

Magnetoencephalography (MEG) is increasingly being used in the preoperative evaluation of pediatric patients with epilepsy. The ability to noninvasively localize ictal onset zones (IOZ) and their relationships to eloquent functional cortex allows the pediatric epilepsy team to more accurately assess the likelihood of postoperative seizure freedom, while more precisely prognosticating the potential functional deficits that may be expected from resective surgery. Confirmation of clinically suggested multifocality may result in a recommendation against resective surgery because the probability of seizure freedom will be low. Current paradigms for motor and somatosensory testing are robust. Paradigms allowing localization of those regions necessary for competent language function, though promising, are under continuous optimization. MR imaging white matter trajectory data, created from diffusion tensor imaging obtained in the same setting as the localization brain MR imaging, provide ancillary information regarding connectivity of the IOZ to sites of rapid secondary spread and the spatial relationship of the IOZ to functionally important white matter bundles, such as the corticospinal tracts. A collaborative effort between neuroradiology, neurology, neurosurgery, neuropsychology, technology, and physics ensures successful implementation of MEG within a pediatric epilepsy program.

Screening for renal disease: the role of the practice nurse

Screening tests for renal disease are inexpensive, easy to carry out and simple to interpret. Nurses in general practice can provide screening for high-risk populations and interpret the results of these tests. Practice nurses can also provide patient information about renal disease, which will both improve patients' quality of life and save time and money for the NHS.

Art macabre: resurrectionists and anatomists

The teaching of anatomy in England and Scotland from the 16th to the 19th centuries was carried out by the Companies of Barber Surgeons and also there were a number of private schools. The only sources of material for dissection and study were the gallows or the grave and the supply from the former was limited by law. Therefore the latter became the source of a saleable commodity, and so the profession of grave robbing became established. The taking of bodies was abhorrent to the populace, fights and riots would sometimes occur and public outrage was directed towards anatomists. The passing of the Anatomy Act of 1832 helped bring an end to the grisly business of snatching bodies, but the supply of material for study still remained a problem. In the 1920s there was a change in public attitude toward dissection which resulted in an increase in the donation of bodies.

Cultured human retinal pigment epithelial cells differentially express thrombospondin-1, -2, -3, and -4

Thrombospondins are a family of at least five proteins (TSP-1 to -4 and cartilage oligomeric matrix protein or COMP) whose functions are indeterminate. Distribution differences between family members suggest each protein may have some distinct functions. The retinal pigment epithelium (RPE) has divers unusual roles for an epithelia and can produce TSP-1. However, the wide range of RPE activities suggests that, if different thrombospondin family members do have different functions, RPE may express thrombospondins additional to TSP-1. Therefore, we analysed expression of thrombospondin isoforms by RPE using reverse-transcription-linked polymerase chain reaction. Cultured cells exhibited differential expression of TSP-1 to -4; TSP-2 and TSP-4 appearing later in culture than TSP-1 and TSP-3. In situ RPE expressed mRNA for TSP-1 to -4. No COMP mRNA was detected in RPE. These observations suggest that thrombospondin isoforms are regulated differently by the cells and that these proteins may have different functions in the RPE.

Duels, doctors and death

Duelling as a method of settling disputes between gentlemen was practised in the British Isles and on the Continent from the 16th to the beginning of the 20th century. In early duels the victory would go to the better swordsman, but the use of pistols not only made the contest more deadly, but also more democratic. The social aspects, the indications for a challenge, the material and methods and the mortality and morbidity of the contest are considered. Mention is made of a case in which John Hunter was consulted. Its management, progress and autopsy findings are described together with Hunter's thoughts about it and the management of similar wounds.

Robert Liston and vascular surgery

Robert Liston was a general surgeon who dealt with all conditions that were presented to him, and in his practice saw a number of cases that involved the vascular system. These were mainly wounds of vessels, aneurysms and vascular tumours. His writings on the subject have been reviewed with some examples of the cases he had to treat.

Robert Liston: surgeon extraordinary

Robert Liston was probably the best surgeon in his day, being noted for his skill and his speed as an operator. His life as surgeon, teacher and writer have been reviewed. Examples of some of his cases are given to illustrate the outstanding ability of this man in the pre-anaesthetic era.

Deriving opera from operation

Male castration has been practised for centuries in many parts of the world. In Italy in the 16th to the 19th centuries it was performed for the purpose of preserving the soprano voice of boys. The castrati performed in the church choirs, but in the field of opera they achieved the popularity and status of the modern day rock singers. An outline of the operative procedure is given with its physiological consequences, and mention is made of some of the singers who achieved fame at that time. Recently an attempt has been made to reproduce the sound of the castrato voice using the facilities of modern electronic technology.

Further clinical clarification of the muscle dysfunction in cervical headache

The Headache Classification Committee of the International Headache Society listed impairments in cervical muscle function as criteria for headaches of cervical spine origin. Fifteen subjects with cervical headache and 15 controls were tested for the frequency of abnormal responses to passive stretching and abnormal muscle contraction. A new test of cranio-cervical flexion was used to assess the contraction of the deep neck flexors. Results indicated a trend towards a higher frequency of abnormal response to passive stretching of the muscles examined in the cervical headache group but only the upper trapezius proved significantly different to the control group. Deep neck flexor muscle contraction was significantly inferior in the cervical headache group. From the perspective of physical characterization of cervical headache, it appears that response from passive stretch of muscle may not be a strong criterion for cervical headache but deep neck flexor performance may have potential to identify musculoskeletal involvement in headache. The finding may also provide positive directions for conservative treatment of cervical headache.

Arterial disease in antiquity

The study of papyrus writings and of mummified human remains provides an insight into the diseases and the practice of medicine in ancient times. Paleopathology, developed in the latter part of the last century and now incorporating modern technology and diagnostic techniques, has shown that arterial disease was not uncommon and that the arterial lesions of 3000 years ago were no different from those we see today.

Amputation through the ages: the oldest major surgical operation

Amputation has been practised since neolithic times for punitive, therapeutic and ritualistic reasons. Until the development and adoption of general anaesthesia, it was the most major operation to which a surgeon could aspire and a speedy technique was essential. Many famous names have been associated with this operation in both military and civilian surgery.

Saints in surgery

There are nearly 300 saints whose names are associated with diseases or the cure of the sick and this relationship has come about either by some miracle attributed to them or by some aspect of their martyrdom. Some diseases have a number of saints as patrons and some saints have many different patronages. A selection has been made of some that have an association with surgical conditions.

The effects of research on clinical practice: the use of restraints

The investigators have conducted a series of four descriptive, clinical studies to examine the nature of restraint use in extended care and nursing home units in a veterans' facility. Based on the findings of three of these studies, staff education and policy changes were implemented with the intent of decreasing the use of restraints. The present and fourth study in the series examines whether the use of restraints decreased from 1990 to 1993, after policy changes and staff education were initiated. Findings indicate that the frequency of restraint use decreased by almost half, from 25% to 14%. In addition, falls did not increase, but those falling were less likely to be restrained. These findings illustrate the importance of research in setting a course for positive change in clinical practice.

Muskets, musket balls and the wounds they made

Gunshot wounds are a common occurrence today in both military and civilian situations. This paper discusses the development of the weapons, their capabilities, the type of wounds produced and their management in earlier times. A brief comparison is made with the wounds produced by modern firearms. It may be concluded that the earlier wounds were simpler due to the lower velocity of the projectile and therefore a more conservative approach to treatment was acceptable.

Speech-language patterns in a child with moya moya disease

Moya Moya disease is a cerebrovascular condition associated with occlusion of the terminal portion of the internal carotid artery along with the appearance of an abnormal net-like system of collateral blood vessels. This paper presents a description beginning in 1973 over a 6-yr. period of the speech-language performance of a Caucasian female diagnosed with the disease.

Extended care and nursing home staff attitudes toward restraints. Moderately positive attitudes exist

1. The average score on the Restraint Questionnaire for Staff indicated that the extended care and nursing home staff members in the study presented had moderately positive attitudes toward using restraints. 2. There were no significant differences in attitude scores based on gender, position, education, or clinical experience. 3. Collaborating with another professional, especially a physician, was related to a more positive attitude toward restraints; this effect approached statistical significance. 4. Sixty-five percent of the staff could offer no alternatives to restraining a patient; for those who could offer an alternative, increasing staff size was cited most frequently.

Patient and family perceptions of restraints

Based on a holistic philosophy that aging persons' most primary need is that of autonomy and freedom, this qualitative descriptive study examined patients' and their family members' perceptions of the restraint procedure. Twenty-five restrained patients were interviewed, and 19 of their family members completed mailed surveys to describe their perceptions about restraints. Results indicated that the majority of patients (52%) expressed negative feelings about being restrained. Family members expressed a wide variety of feelings and were ambivalent about seeing a loved one restrained. Implications are that nursing needs to become committed to the philosophy of autonomy and freedom for elderly persons.

Institutional policy: use of restraints in extended care and nursing homes

1. The percentage of patients restrained on these nursing home and extended care units was 32%, similar to that for other nursing home studies. 2. The archetypical restrained patient was older, new on the unit, had altered thought processes and a high potential for injury, and required extensive nursing care. Typically, the type of restraint a patient wore was a vest posey, on the day shift while in his room. 3. The most frequent rationale given by nurses for applying restraints was to prevent patient falls; however, half the time, this rationale was not charted. 4. Upon examining institutional restraint policy, nurses should be prepared to implement changes in documentation format, provide staff education regarding restraint use and alternatives available, institute a rehabilitative and restorative nursing care and fall prevention program, redesign the physical environment, and designate adequate resources for an effective diversion activity program.

Saint Anthony's fire revisited. Vascular problems associated with migraine medication

Ergotamine and related compounds have been used for many years in the management of migraine. This review highlights the potential for toxic effects upon the arterial system which may arise from the use of ergot medications. Data on four female patients aged from 30 to 49 years were collected retrospectively from in-patient records and out-patient follow-up between 1978 and 1990. All four patients presented with the symptoms and signs of arterial obstruction and all had been prescribed ergot preparations as treatment and prophylaxis of migraine, for periods ranging from three to 12 years. Two patients had an acute arterial obstruction that resolved completely when the migraine medication was withdrawn. Two had chronic obstructions and radiological and surgical examination gave evidence of arterial stenosis. These two patients were treated with bypass surgery. Review of the literature indicated that other authors had described similar cases but without specifying the methods of data collection. This report supports the findings of others regarding the toxic effects of ergot preparations upon the arterial system, which may take the form of chronic or acute obstruction. General practitioners and physicians should be aware of the possible complications arising from prolonged or excessive use of ergot medications.

Chelation treatment of atherosclerosis

Edetate disodium (EDTA) is a chelating agent which has no place in the treatment of atherosclerosis and its complications. Also, its toxic effects can cause other problems which may lead to a fatal outcome. Proper investigation and treatment may sometimes be delayed by a patient's faith in such therapy. The dangers of chelation therapy, and the opinion of the Commonwealth Department of Health and other writers on this subject, are stated.

RUPTURE OF THE DIAPHRAGM : (With report of two cases)

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