Active cancellation of stray magnetic fields in a Bose-Einstein condensation experiment

A method of active field cancellation is described, which greatly reduces the stray magnetic field within the trap region of a Bose-Einstein condensation experiment. An array of six single-axis magnetic sensors is used to interpolate the field at the trap center, thus avoiding the impractical requirement of placing the sensor within the trap. The system actively suppresses all frequencies from dc to approximately 3000 Hz, and the performance is superior to conventional active Helmholtz cancellation systems. A method of reducing the field gradient, by driving the six Helmholtz coils independently, is also investigated.     

Spectral transmission and short-wave absorbing pigments in the fish lens--I. Phylogenetic distribution and identity

Fish lens transmission was found to vary depending on the type and concentration of short-wave absorbing compounds present within the lens. Pigments extracted from lenses of ten species were identified as mycosporine-like amino acids (mainly palythine, palythene and asterina-330, lambda maxs around 320-360 nm) which are also thought to be present in the majority of the 120 species examined here. A novel mycosporine-like pigment with lambda max 385 nm was isolated from the lens of the flying fish, Exocoetus obtusirostris, while lenses of several closely related tropical freshwater species were found to have high concentrations of the tryptophan catabolite 3-hydroxykynurenine (lambda max 370 nm). The type of lens pigment a species possesses and its concentration depends upon both the animal's phylogenetic group and its "optical niche".     

Outpatient psychotherapy with dangerous clients: A model for clinical decision making.

The precedent-setting 1976 judicial decision of Tarasoff v. Regents of the University of California established a duty to protect whereby psychotherapists are expected to exercise reasonable care to protect the potential victims of their clients' violent behavior. However, no standard of care for dangerous clients has been established. In this article, the authors present a model for clinical decision making to determine the best interventions for dealing with dangerous outpatient clients. The model takes into account the degree of violence risk and the strength of the therapeutic alliance. Four cases are presented to illustrate the application of the model. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Tau Is Truncated in Five Regions of the Normal Adult Human Brain

The truncation of Tau is thought to be important in promoting aggregation, with this feature characterising the pathology of dementias such as Alzheimer disease. Antibodies to the C-terminal and N-terminal regions of Tau were employed to examine Tau cleavage in five human brain regions: the entorhinal cortex, prefrontal cortex, motor cortex, hippocampus, and cerebellum. These were obtained from normal subjects ranging in age from 18 to 104 years. Tau fragments of approximately 40 kDa and 45 kDa with an intact N-terminus retained were found in soluble and insoluble brain fractions. In addition, smaller C-terminal Tau fragments ranging in mass from 17 kDa to 25 kDa were also detected. These findings are consistent with significant Tau cleavage taking place in brain regions from 18 years onwards. It appears that site-specific cleavage of Tau is widespread in the normal human brain, and that large Tau fragments that contain the N-terminus, as well as shorter C-terminal Tau fragments, are present in brain cells across the age range.     

Potential Effect of Cavitation on the Physical Properties of Interesterified Soybean Oil Using High-Intensity Ultrasound: A Long-Term Storage Study

The objective of this research was to evaluate if cavitation events generated during sonication (20 kHz, 216 μm amplitude, 10 s) are responsible for changes in physical properties of a fat with low levels of saturated fatty acids and if these changes are maintained during storage. The fat was crystallized at 24 and 34 °C and stored at 25 °C for up to 24 weeks. An increase in solid fat content and melting enthalpy was observed for sonicated samples crystallized at 34 °C and an increase in elasticity was observed for sonicated samples crystallized at 24 °C (P < 0.05). Hardness increased in sonicated samples crystallized at 24 and 34 °C (P < 0.05) after 60 min of crystallization and after 24 weeks storage. Elasticity of non-sonicated samples crystallized at 24 °C decreased (P < 0.05) after storage at 25 °C for 48 h while it remained constant in sonicated samples. Sonicated samples had more, and smaller crystals compared to the non-sonicated ones. No significant change was observed in physical properties of sonicated samples crystallized at 24 °C and 34 °C during the 24 weeks of storage. Sonication at 24 °C was less efficient at changing the physical properties of the fat compared to 34 °C; however, the number of subharmonic components generated during sonication at these two temperatures was not affected by crystallization temperature. These results suggest that changes in physical properties are associated with secondary effects of sonication such as bubble streamers rather than changes in cluster dynamics.     

Antibiotics for elimination of mycoplasmas and ureaplasma from bovine semen.

Minocin at 500 micrograms/ml of semen extender eliminated ureaplasma from naturally or artificially infected bovine semen. Minocin with lincospectin eliminated Acholeplasma laidlawii, Mycoplasma bovigenitalium, bovis, canadense, and arginini from artificially infected semen. Stabilization times of 15 min at 35 C and 3 h at 4 C are important considerations to maximize antibiotic activity.     

Reference data for ultrasonic bone measurement: variation with age in 2087 Caucasian women aged 16-93 years

Data from the measurement of broadband ultrasonic attenuation (BUA) and speed of sound (SOS), using the Lunar Achilles ultrasonic densitometer, were collected for Caucasian women from five centres in the United Kingdom (Leeds, London, Nottingham, Lincoln and Sheffield). After correcting for machine variability at each site, the data were combined into a central reference database comprising 2087 women aged 16-93 years. The data are presented in 5-year bands and show a mean fall of 0.36% per year for BUA and 0.08% per year for SOS in the 60 years following the attainment of peak bone mass. This fall in BUA compares with that observed using dual energy X-ray absorptiometry studies of the lumbar spine and femoral neck of 0.32% per year and 0.44% per year, respectively, for the age range 25-65 years.     

Insulin secretion in relation to fatness in cattle

The insulin secretory response to tolbutamide was examined in cattle to determine: whether this agent is insulinogenic in this species, what effect age has on insulin secreting ability, and whether the insulin response is related to body fatness. Intravenous injection of sodium tolbutamide (27 mg kg^?0.75) caused a three- to sevenfold rise in plasma insulin concentration, but the response was delayed and protracted in comparison with that seen in non-ruminants. The insulin response was higher at 20 than at 12 months of age. The insulin response was not related to the proportion of dissectible fat in the empty body, and it was lower in Hereford than Friesian steers despite the Herefords being slightly fatter. It was concluded that tolbutamide is insulinogenic in cattle and its effectiveness increases with age. Unlike the non-ruminant, there is no association between fatness and insulin response to tolbutamide in cattle compared at the same age.     

Contextual constraint and schizophrenic language.

Compared 16 hospitalized schizophrenic patients and 16 nonpsychiatric patients for the degree of facilitation of contextual constraint in memory. Ss were matched for intelligence, age, education, duration of illness, and socioeconomic level. All Ss listened to 4 taped word passages of different linguistic structure: normal and anomalous sentences, and semantically related and random word-strings. Ss differed in recall on all conditions, with the greatest difference between S groups occurring on normal sentences. Both S groups showed greater recall on passages emphasizing semantic components than on those with syntactic. Results suggest that the schizophrenic difficulty in communication may be influenced by lack of memory facilitation due to contextual constraints. (24 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)