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Experiments were performed with 30 11 cm × 42.5 cm × 5.5 cm NaI(Tl) detectors to better understand their positional response. Spectra were collected using 0.02 to 0.15 MBq point sources of Am, Cs, Co, and Ba positioned on lines parallel and perpendicular to the long axis of the crystal along both the narrow and wide detector faces as well as at different distances from them. A greater density of positions was sampled at the ends of the detector, and repeated measurements were made to examine potential gain drifts during the experiment. Spectroscopic peak counts, spectroscopic pulse heights, and net counts were analyzed. Empirical equations were fit to the aforementioned data for each specific source energy as a function of source position. In addition, a Monte Carlo radiation transport code was used to simulate the expected positionally variable response based solely upon radiation absorption. The simulated radiation transport efficiency functions were compared to the experimental data. The effects of the geometric radiation efficiency, the attenuation and scattering of emitted light within the scintillation crystal, and combined effects such as nonuniformity of the photomultiplier tube, photocathode response, and crystal irregularities were then distinguished. Functions describing each effect were derived. The results suggest potential new corrections to data obtained with large scintillation detectors as well as a novel approach to partial positional gamma-ray detection with minimal collimation, given that the energy resolution is within reason for particular photopeaks.

Optically stimulated luminescent (OSL) dosimeters are devices used for measuring doses of ionizing radiation. Signal is stored within an OSL material so that when stimulated with light, light of a specific wavelength is emitted in proportion to the integrated ionizing radiation dose. Each interrogation of the material results in the loss of a small fraction of signal, thus allowing multiple interrogations leading to more accurate measurements of dose. In order to reuse a dosimeter, the residual signals from prior doses must be taken into account and subtracted from current readings, adding uncertainty to any future measurements. To reduce these errors when they become large, it is desirable to completely clear the stored signal or anneal the dosimeter. Traditionally, heating the material has accomplished this. In a commercially available dosimeter badge system, the OSL material Al2O3:C is incorporated into a plastic slide that would melt at the necessary high temperatures, which can reach 900 °C, required for annealing. Fortunately, due to the material's high sensitivity to light, OSLs can be optically annealed instead. In order to do this, an affordable OSL dosimeter annealer was designed with inexpensive, exchangeable blue, green, and white high intensity light-emitting diodes (LEDs). Several dosimeters were repeatedly annealed for recorded intervals and then read out. A single dosimeter was partially annealed through repeated interrogations with the LED array from a commercial reader. The signal loss due to the exposure to each light was analyzed to determine the practicality and efficiency of each color. The rate and extent of signal loss was dependent not only on the spectrum of annealing light but on the initial signal levels as well. These findings suggest that blue LEDs are the most promising for effective and rapid clearing of the OSL material Al2O3:C.

Optically-stimulated luminescent dosimeters are capable of being interrogated multiple times post-irradiation. Each interrogation removes a fraction of the signal stored within the optically-stimulated luminescent dosimeter. This signal loss must be corrected to avoid systematic errors in estimating the average signal of a series of optically-stimulated luminescent dosimeter interrogations and requires a minimum number of consecutive readings to determine an average signal that is within a desired accuracy of the true signal with a desired statistical confidence. This paper establishes a technical basis for determining the required number of readings for a particular application of these dosimeters when using certain OSL dosimetry systems.

Due to heightened fear surrounding the possibility of future terrorism involving nuclear weapons and radiological dispersive devices, compounded by nonroutine nuclear power plant releases such as from emergencies or accidents, interest in contamination levels of environmental radiation has spiked. This project sought to develop a continuously operational radiation-monitoring system, with graphically visualized data easily accessible to the public. Because this continuing project is housed at a university facility, it bears no connection to perceived political or commercial interests, generally increasing the credibility of the endeavor. Outdoor weather and radiation parameters were gathered by sensors installed on the rooftop of a two-story building. A display and cloud service website was used to project the live data in an understandable format. A correlation was observed between weather and visibly heightened levels of gamma radiation. The goal of this paper is to share and highlight the overall hardware selection and the unique software challenges encountered when developing a robust collection and analysis system, along with the challenges of displaying meteorological and radiological data in a clear and concise fashion.

Commercially available gamma-ray imaging spectrometers have been introduced recently and are currently undergoing investigations for various applications in nuclear power plants, environmental management, and medical environments. A Compton imaging gamma-ray spectrometer uses an array of detectors or a single position-sensitive crystal to create planar images of radionuclide distributions. The typical software included with these devices creates images of specific radionuclides using only the counts under their known gamma emission photopeaks. This approach prevents the direct imaging of scattered radiation, which is of interest for many radiation protection applications. In this paper, a technique for imaging radiation scatter or portions of the scatter spectrum is implemented. This involves the creation of a virtual radionuclide in software with peaks placed throughout the backscatter continuum of interest and then imaging that virtual radionuclide in the post-processing software. This technique is used to image the Compton scatter successfully from a polymethyl-methacrylate (PMMA) phantom placed in a Cs irradiator beam. Measured scatter energies were found to be within 15% of the expected values, sufficient to predict scatter behavior and individually measure separate sources of scatter at different angles.

INTRODUCTION: Simple laboratory tests of upper motor neuron involvement in amyotrophic lateral sclerosis (ALS) are not available. Intermuscular coherence has been shown to distinguish patients with primary lateral sclerosis, a pure upper motor neuron disorder, from normal subjects, suggesting it could be useful for assessing ALS. OBJECTIVE: To determine whether intermuscular coherence can distinguish ALS patients from normal subjects. METHODS: We measured biceps brachii and brachioradialis activity using surface electromyography while subjects held the elbow at flexion and the forearm in semi-pronation. Intermuscular coherence was calculated between 20 and 40 Hz in 15 ALS patients and 15 normal subjects. RESULTS: On average, intermuscular coherence was 3.8-fold greater in normal subjects than in ALS patients (P

To evaluate the anti-inflammatory and analgesic activities of leaf extract of Melanthera scandens (M. scandens).The crude leaf extract (39-111 mg/kg) of M. scandens was investigated for anti-inflammatory and analgesic activities using various experimental models. The anti-inflammatory activity was investigated using carragenin, egg-albumin induced oedema models, while acetic acid, formalin-induced paw licking and thermal-induced pain models were used to evaluate the antinociceptive property.The extract caused a significant (P0.05 - 0.001) dose-dependent reduction of inflammation and pains induced by different agents used.The leaf extract possesses anti-inflammatory and analgesic effects which may be mediated through the phytochemical constituents of the plant.

Concerns have been raised that persons with serious illnesses participating in high-risk research, such as PD patients in sham surgery trials, have unrealistic expectations and are vulnerable to exploitation. A comparison of enrollees and decliners of such research may provide insights about the adequacy of decision making by potential subjects. We compared 61 enrollees and 10 decliners of two phase II neurosurgical intervention (i.e., cellular and gene transfer) trials for PD regarding their demographic and clinical status, perceptions and attitudes regarding research risks, potential direct benefit, and societal benefit, and perspectives on the various potential reasons for and against participation. In addition to bivariate analyses, a logistic regression model examined variables regarding risks and benefits as predictors of participation status. Enrollees perceived lower risk of harm while tolerating higher risk of harm and were more action oriented, but did not have more advanced disease. Both groups rated hope for benefit as a strong reason to participate, whereas the fact that the study's purpose was not solely to benefit them was rated as "not a reason" against participation. Hope for benefit and altruism were rated higher than expectation of benefit as reasons in favor of participation for both groups. Enrollees and decliners are different in their views and attitudes toward risk. Although both are attracted to research because of hopes of personal benefit, this hope is clearly distinguishable from an expectation of benefit and does not imply a failure to understand the main purpose of research.

Subjects enrolled in studies testing high risk interventions for incurable or progressive brain diseases may be vulnerable to deficiencies in informed consent, such as the therapeutic misconception (TM). However, there is a continuing debate about the definition and measurement of TM, making assessments of TM controversial. In this qualitative pilot study of persons enrolled in a phase I test of gene transfer for Parkinson’s disease, we developed and tested an interview guide focusing on how the subjects made their decision to participate, with an emphasis on understanding the subject as the unit of interest, rather than focusing only on isolated statements. The results indicate that a subject’s understanding of the purpose of research is best explored in juxtaposition to the subject’s motivation for participation. Doing so reveals potential avenues for measuring and preventing TM.

This paper explores the technologies and capabilities of the SensorPod ™ System, a suite of technologies that has been developed to allow ballistic placement of tethered and wireless sensors into remote locations inaccessible by traditional hand- placed sensors or robotic explorers. These locations include potentially hazardous areas, or areas that would become contaminated or disturbed due to the placement of traditional sensor packages. The SensorPod ™ product line includes modular components to deploy individual or arrays of sensor, as well as support technologies such as compact mechanisms to enable the sensor packages to orient themselves relative to the surface and deploy short booms to achieve limited elevation after deployment.

There are over 14 million people in the United States who are classified as ‘low vision’, with visual acuity no better than 20/40 with best correction in their best eye. Of these, over 3 million are classified as ‘legally blind’, with visual acuity no better than 20/200 with the best correction in the better eye [1]. All of these people suffer from an inability to perform some or all of the simple daily tasks that the majority of ‘normal sighted’ people take for granted. These include, but are not limited to, navigating in- and outdoors; reading a newspaper or medicine bottles; recognizing faces. Helping as many of these people as possible perform these tasks is a daunting task, and requires an interactive system capable of extracting pertinent data from the environment, enhancing the data, and then presenting it to the user in a form that is well understood and relevant to the user’s task. A lightweight, small, inexpensive, and bright display device with a large field of view and high resolution is a key component of such a system.

The design of a wearable low vision aid (WLVA) encompasses a wide range of design variables and made more complex by rapidly changing camera, micro-display, and computer technologies, and with the unique needs of the partially sighted user. Many of the WLVA design challenges have been documented by Massof [1] using miniature cathode ray tube (CRT) displays. Our goal.is to develop new scanning light micro-displays for low-cost WLVAs. Originally proposed by Peli [2], we are designing WLVAs that scan light from a laser or light emitting diode (LED), directly toward the eye. As the light beam raster scans across the retina, the mind perceives it as a full image. This display technology is called retinal light scanning, which produces images of high brightness from the laser or LED source and great depth-of-focus because of the narrow beam of light. A recent reading performance study demonstrated significantly higher reading rates of a minority of partially sighted individuals using a retinal scanning Virtual Retinal Display (VRD) versus a CRT [3]. We are in the process of researching low-cost optical scanners [4], novel human interface designs [5], and a computer-aided, decision-based design process to aid in the development of WLVAs. The initial results from our computer-aided design process are presented here.

The location of the international 10–20 system electrode positions and 14 fiducial landmarks are described in cartesian coordinates (±1.4 mm average accuracy). Six replications were obtained on 3 separate days from 4 normal subjects, who were compared to each other with a best-fit sphere algorithm. Test-retest reliability depended on the electrode position: the parasagittal electrodes were associated with greater measurement errors (maximum 7 mm) than midline locations. Location variability due to head shape was greatest in the temporal region, averaging 5 mm from the mean. For each subject's electrode locations a best-fitting sphere was determined (79–87 mm radius, 6% average error). A surface-fitting algorithm was used to transfer the electrode locations and best-fitting sphere to MR images of the brain and scalp. The center of the best-fitting sphere coincided with the floor of the third ventricle 5 mm anterior to the posterior commissure. The melding of EEG electrode location information with brain anatomy provides an empirical basis for associating hypothetical equivalent dipole locations with their anatomical substrates.

Optical fibers are microfabricated and piezoelectrically vibrated to produce rectilinear scan patterns. By coupling a laser to the optical fiber and projecting the collimated light directly to the viewer's eye, the result is a proposed low-cost, spectacle-mounted, wearable low vision aid.

The introduction of topical antibiotics for acne vulgaris has ushered in a new era in the treatment of this troublesome disorder. Tetracycline, erythromycin, and clindamycin can now be prepared in lotion form in vehicles that are capable of carrying the antibiotic into the follicular canal, where the primary lesion of acne occurs. Topical antibiotics are practically as effective as oral antibiotics in treating acne and are particularly useful for mild papular acne of puberty and early adolescence and papular-pustular acne of adult women. Use of topical antibiotics avoids the possibility of the adverse effects of systemic therapy; the side effects from the formulations reported here are negligible. Above all, antibiotic lotions do not produce the dryness and scaling that occur with most other topical acne preparations.

Seven important therapeutic measures in managing acne are described, for the treatment of the 7 types of acne. These therapeutic measures are retinoic acid, benzoyl peroxide gel, topical antibiotics, oral antibiotics, intralesional corticosteriods, liquid nitrogen and oral corticosteroids.

The rabbit ear model has been proposed as a useful bioassay to establish the comedogenic and acnegenic qualities of chemical compounds and finished products, pharmaceutical and cosmetic, for topical application. This review highlights the many problems in performance of the test method, the absence of correlation with experience in the human, and, consequently, the serious limitations to the conclusions that can reasonably be drawn, especially for the clinical dermatologist.

IT IS KNOWN that beryllium compounds can produce acute pneumonitis, 1 dermatitis 2 and chronic granulomatous changes in the lungs, lymph nodes and skin. 3 Until recently, case reports have pertained to workers employed in the processing of beryllium ore and in such industries as the manufacture of fluorescent lamps, the casting of beryllium copper alloys, the production of electric signs and the manufacture of special ceramics. With the widespread use of fluorescent light bulbs, it is apparent that the hazard has extended to the general public. Chronic granulomas appearing at the sites of superficial or deep lacerations caused by broken fluorescent light tubes have been reported. 4 Fluorescent lamps are lined with a coating composed of the beryllium phosphor, zinc manganese beryllium silicate, containing from 0.5 to 2 per cent beryllium. We are reporting 2 additional instances of cutaneous granuloma following laceration of the skin with

A patient with keratoma hereditaria multilans (KHM), a young white girl, presented the following classic features of this rare disease: familial palmar and plantar hyperkeratosis beginning early in life, starfish-like keratoses of the dorsa of hands and feet, linear keratoses of elbows and knees, and constriction of digits beginning in the teens. A classification of the hereditary and nonhereditary diseases which exhibit digital constriction is briefly presented. The majority of the hereditary diseases with digital constriction have palmar and plantar hyperkeratosis, whereas the nonhereditary conditions are usually not keratotic. In addition to the usual KHM findings our patient presents a high-frequency hearing loss; an unusual, pseudopelade-type alopecia; and transient, plantar bullae. The disease is probably a variant of mal de Meleda.

The halo nevus can be defined as a pigmented nevus with an obvious depigmented zone about it. Recent observations have indicated that these lesions will undergo self-involution. This article presents the variety of histopathologic pictures seen and demonstrates the gross clinical changes that can occur in the nevus (change in color, increase in size, scaling, and crusting) during this process of self destruction. The association of these clinical and pathologic changes might make one consider the diagnosis of malignant melanoma. The benign significance of these changes in a halo nevus is stressed. In addition, other aspects of halo nevi such as distribution, configuration, multiplicity, association with vitiligo, and the fate of the halo are presented.

Two patients with tinea nigra were treated with tolnaftate solution. Temporary clinical clearing occurred in one, but in the other there was no clinical improvement. Mycologic findings, however, remained positive in both cases. Tolnaftate solution did not inhibit the growth of these strains ofCladosporium werneckiiin vitro.