Application of bispectral speckle imaging to near-diffraction-limited imaging in the presence of unknown aberrations.

A laboratory experiment that demonstrates near-diffraction-limited imaging of a detailed object in the presence of unknown fixed aberrations in the imaging system is described. A random-phase plate is introduced in a pupil plane of the imaging system to eliminate the effect of fixed aberrations in the system. We employ a bispectral speckle imaging technique to recover the object from speckled images affected by both the random-phase fluctuations induced by the random-phase plate and the fixed aberrations present in the imaging system. For the case where the random phase is assumed to obey Gaussian statistics an approximate form of the bispectral speckle transfer function is obtained with an asymptotic expansion. This approximate form of the transfer function shows the diffraction-limited nature of bispectral speckle imaging when the standard deviation of the random-phase fluctuations is of the order of a wavelength of light. Experimental results are presented for fixed aberrations associated with lens tilt and defocus in the imaging system.

Required energy for a laser radar system incorporating a fiber amplifier or an avalanche photodiode.

The transmitted energy required for an airborne laser radar system to be able to image a target at 20 km is investigated. Because direct detection is being considered, two methods of enhancing the received signal are discussed: (1) using an avalanche photodiode (APD) as the detector and (2) using a commercial fiber amplifier as a preamplifier before a photodetector. For this analysis a specified signal-to-noise ratio was used in conjunction with the radar range equation, which includes the effects of atmospheric transmission and turbulence. Theoretical analysis reveals that a system with a fiber amplifier performs nearly the same as a system incorporating an APD.

How effective in your training of volunteers?

This work addresses one of the basic concepts of volunteer management, a three-level program for training volunteers. The author addresses the need for an appropriate amount of training, the important categories of training for volunteers and the use of volunteers as trainers of other volunteers. She presents a perspective of training of volunteers which is applicable to many types of organizations utilizing volunteers and to a diversity of volunteer services. The author's direct and simple approach to this aspect of volunteer management serves as a reminder of the important part training plays in the volunteer experience.

Imaging thermal objects with photon-counting detectors.

A photon-counting camera is used to generate images of thermal (blackbody) objects. Analytical estimates of the count rates that can be obtained for thermal objects in the 300-800-K temperature range are given for several different photocathode materials. Images generated with a photon-counting camera are compared with those obtained with infrared cameras that operate in the 3-5 and 8-12-microm ranges. It is found that high-resolution images of thermal objects can be generated with the photon-counting camera. The noise-equivalent differential temperature that can be obtained with a photon-counting camera is given as a function of the number of detected photoevents. Patternrecognition experiments that use low-light-level (quantum-limited) images of thermal objects are reported. In the experiments, photon-limited images of thermal objects are correlated with a reference function that is stored in computer memory. The number of detected photoevents required to reliablydistinguish between two thermal objects is determined and compared to the noise-equivalent differential temperature figure of merit.

FK506 and pertussis toxin distinguish growth-induced locomotor activation from attractant-stimulated locomotion in human blood lymphocytes.

The locomotor capacity of human lymphocytes is cell cycle-related. Many small blood lymphocytes are non-motile but acquire locomotor capacity in G1 on appropriate activation with e.g. anti-CD3 antibody (aCD3) for T cells, or interleukin-4 (IL-4) for B cells. Once this capacity is acquired, the cells can then respond by polarization and locomotor to chemoattractants such as IL-8 or foetal calf serum (FCS). These two stages in the locomotor process were distinguished by the use of two inhibitors, FK506 and pertussis toxin. FK506 caused a dose-dependent inhibition of cell cycle-related induction of locomotor capacity both of anti-CD3-cultured T cells and IL-4-cultured B cells, with an ID50 of less than 1 ng per ml. This was measured in assays both of morphological polarization and of locomotion into collagen gels. FK506 has no effect on chemoattractant-induced polarization. Conversely, pertussis toxin has little inhibitory effect on growth-induced locomotor capacity, but is an effective inhibitor of the immediate polarization response following addition of FCS or IL-8 to lymphocytes either direct from blood or after overnight culture. These results suggest that different signalling pathways are involved in the two stages. Growth-related locomotor activation does not involve a pertussis toxin-sensitive G protein and may be signalled in the same way as other mitogen-induced events which are sensitive to FK506 and cyclosporin. On the other hand, the locomotor response to attractants, on this and earlier evidence, is transduced via a pertussis toxin-sensitive G protein. However, after prolonged (24-48 hr) culture in the presence of pertussis toxin, lymphocyte locomotor responses to attractants become insensitive to pertussis toxin.

Simian immunodeficiency virus/delta-induced immunodeficiency disease in rhesus monkeys: relation of antibody response and antigenemia.

Infection of the rhesus macaque (Macaca mulatta) with simian immunodeficiency virus (SIV) induces a disease similar to AIDS. We compared SIV-specific antibody and antigenemia with the progression of disease in monkeys experimentally infected with SIV/Delta isolates that varied in pathogenicity. Western blot, immunoprecipitation, and sandwich enzyme-linked immunosorbent assay of serial sera from macaques infected with attenuated virus revealed a persistent antibody response and no evidence of SIV antigenemia. Immunosuppressed macaques without central nervous system (CNS) infections responded similarly to initial infection, but antibody specific for gag or, less frequently, to gag and env determinants declined predictably before clinical disease. Monkeys with CNS infections, however, had little, if any, detectable antibody to either envelope or gag proteins, regardless of the duration of survival. SIV/Delta-specific antigenemia, evident only in immunodeficient monkeys, fluctuated reciprocally with antibody. Our data suggest that SIV/Delta-induced disease is dependent upon antigenemic episodes that, particularly in animals with CNS infection, appear coincident with diminished antibody.

Necropsy findings in rhesus monkeys experimentally infected with cultured simian immunodeficiency virus (SIV)/delta.

Lesions induced in rhesus monkeys by different isolates of simian immunodeficiency virus (SIV)/Delta were studied at necropsy. Four groups of monkeys were inoculated with SIV/Delta isolated from other experimentally infected rhesus monkeys, while one group was inoculated with SIV/Delta from an asymptomatic mangabey monkey. Three rhesus isolates and the mangabey isolate were virulent, killing 75-100% of infected monkeys. One rhesus isolate, which had been extensively passaged in vitro, was attenuated but was restored to virulence by single animal passage. Clinically, infected monkeys had lymphadenopathy, splenomegaly, diarrhea, and a rash. Most monkeys died of enteric disease. The following lesions were seen: weight loss, thymic atrophy, lymphoid atrophy, bone marrow hyperplasia, encephalitis, colitis, amyloidosis, hepatitis, glomerulosclerosis, and the presence of syncytial cells. One Rh Epstein-Barr virus (EBV)-related lymphoma occurred. Opportunistic agents were identified: cytomegalovirus, adenovirus, Cryptosporidia, and Pneumocystis. Shigella and Campylobacter often caused colitis.

Spontaneous rhabdomyosarcoma in a rhesus monkey.

In an adult male rhesus monkey, a large pelvic mass causing lysis of the ilium and destruction of pelvic musculature was diagnosed as a spontaneous rhabdomyosarcoma by the use of histological, ultrastructural and immunohistochemical techniques.

Multidrug chemotherapy of tuberculosis in rhesus monkeys.

Occurrence of tuberculosis caused by Mycobacterium bovis in a colony of rhesus monkeys allowed evaluation of a modern multidrug therapeutic regimen. Fifteen tuberculin positive rhesus monkeys with disseminated tuberculosis were evaluated for extent of disease by radiographic techniques, physical examination and laparotomy prior to treatment. Monkeys were divided into treatment groups of 3, 6 and 12 months duration and were treated once daily with isoniazid, rifampin and ethambutol. All animals survived their treatment course, had marked clinical improvement and rapid resolution of radiographically demonstrable lesions. Lesion regression evaluated by necropsy and histopathology correlated positively with length of treatment interval. Mycobacterium bovis was not isolated from any animal following treatment. Multidrug chemotherapy of tuberculosis was considered successful and practical in rhesus monkeys at the 12 month treatment interval. Chemotherapy may provide a reasonable alternative to destruction of valuable animals infected with tuberculosis.

The lepromin test in rhesus monkeys.

The lepromin test was studied in rhesus monkeys. Six control monkeys which had not been inoculated with Mycobacterium leprae, six monkeys with experimentally induced leprosy, and nine monkeys which had been inoculated with M. leprae but had not developed leprosy were evaluated with 1X, 10X, and 15X lepromin A, with 1X and 10X lepromin M (mangabey monkey derived), with 1X and 25X purified inactivated M. leprae, and with an armadillo mock lepromin. We found that the lepromin test is useful in rhesus monkeys, but that a higher concentration of antigen than is used in humans is required to induce a response in monkeys. Control monkeys appear to be lepromin negative. Animals which have been inoculated and which develop lepromatous leprosy are also negative. Monkeys which are experimentally inoculated with M. leprae and do not develop leprosy become lepromin positive. Monkeys with indeterminate leprosy have reactions intermediate between lepromatous and resistant animals. No monkeys reacted to armadillo tissue. Our results indicate that 10X lepromin A is a useful preparation for the lepromin testing of rhesus monkeys.

Generalized amyloidosis in rhesus monkeys.

Necropsy materials from 57 cases of generalized amyloidosis in rhesus monkeys were reviewed. Clinically, animals with the disease were characterized by cachexia with muscle wasting, recurrent diarrhea, and arthritis. Gross lesions included hepatomegaly, splenomegaly, chronic/active colitis, fibrous strictures of the cecocolic junction, osteoarthritis, and generalized muscle atrophy. Histologic examination revealed minimal to severe deposits of amyloid in the small intestine (100%), spleen (93%), large intestine (67%), liver (40%), lymph nodes (71%), stomach and/or adrenal gland (32%). More amyloid was deposited in the spleen, liver, and small intestine than in other organs. Shigella sp. were isolated from feces in 23% of the cases and 84% had histologic evidence of colitis. Other findings indicated that 100% of the animals had lung mites, 25% had strictures of the cecocolic junction, and 40% had osteoarthritis. Thirty percent of the cases occurred in animals 10 months to 5 years of age, 10% in ages 6 to 10 years, and 60% in animals greater than 10 years old.

Localization of cystic fibrosis locus to human chromosome 7cen-q22.

Cystic fibrosis (CF) is the most common genetic disease in Caucasian populations, with an incidence of 1 in 2,000 live births in the United Kingdom, and a carrier frequency of approximately 1 in 20. The biochemical basis of the disease is not known, although membrane transport phenomena associated with CF have been described recently. Consanguinity studies have shown that the inheritance of CF is consistent with it being a recessive defect caused by a mutation at a single autosomal locus. Eiberg et al. have reported a genetic linkage between the CF locus and a polymorphic locus controlling activity of the serum aryl esterase paraoxonase (PON). The chromosomal location of PON, however, is not known. Linkage to a DNA probe, DOCR1-917, was also recently found at a genetic distance of approximately 15 centimorgans (L.-C. Tsui and H. Donnis-Keller, personal communication), but no chromosomal localization was given. Here we report tight linkage between the CF locus and an anonymous DNA probe, pJ3.11, which has been assigned to chromosome 7cen-q22.

Tarsal navicular stress fractures in runners.

The number of participants in running programs at all levels has increased in recent years. As a consequence, practitioners are more frequently dealing with diagnoses in symptomatic runners. Detection of tarsal navicular stress fractures in long distance runners, including the diagnostic value of radionuclide bone scanning, is discussed.

Problems in polydactyly of the foot.

1. Polydactyly should be treated early. 2. Adequate bone and soft tissue should be removed. 3. One arm of the Y should be removed surgically in the incompletely duplicated Y metatarsal. 4. The incompletely duplicated Y metatarsal shaved to form a single shaft may at first be bowed, but will remodel to form normal or nearly normal bone. 5. The wide metatarsal head associated with a duplicated phalanx should be narrowed surgically to avoid the development of a painful bunion. 6. Short block-like metatarsals remain abnormal. 7. Polydactyly associated with a short first metatarsal and congenital hallux varus carriers a poorer treatment prognosis and may require continuing treatment. 8. Postoperative casting and taping should be utilized to prevent angular deformities and encourage normal forefoot contour.