An Autonomous Palm-Sized Gliding Micro Air Vehicle

This article has concentrated on the development of a set of core technologies key to the realization of an autonomous 2-g glider. One aspect which was not discussed in detail was the ease of construction and low cost of an individual MicroGlider. Integration is simplified through a number of rapid prototyping techniques and the low costs of most components allow rigorous testing to be done without worry of substantial damage.     

Human chromosome 5 sequence primer amplifies Alu polymorphisms on chromosomes 2 and 17

Members of the Alu family of repetitive elements occur frequently in the human genome and are often polymorphic. Techniques involving Alu element mediated polymerase chain reactions (Alu PCR) allow the isolation of region-specific human DNA fragments from mixed DNA sources. Such fragments are a source of region-specific Alu elements useful for the detection of Alu-related polymorphisms. A clone from human chromosome 5, corresponding to locus D5F40S1, was isolated using Alu PCR differential hybridization. Alu elements within this clone were investigated for the presence of potentially polymorphic 3' polyA tails. Primers were devised to amplify the 3' polyA tail of an Alu element present within the clone. One primer, D5F40S1-T, was specific to the DNA flanking the 3' end of the Alu element, and the other primer was homologous to sequences within the element. When these primers were used in PCR reactions, products from chromosomes 2 and 17 (loci D2F40S2 and D17F40S3) were amplified in addition to the expected product from chromosome 5. The most likely explanation for this nonspecific amplification is that the D5F40S1-T primer is located within a low-copy repetitive element that is 3' of the Alu element. This phenomenon presents a potential problem for the identification of region-specific Alu polymorphisms.     

Microstructures and phase selection in rapidly solidified Zn-Mg alloys

The Zn-Mg system has potential glass-forming ability, and therefore studies were made of rapidly solidified zinc-based Zn-Mg alloys containing up to 6 wt% Mg. These alloys exhibited interesting eutectic phase selections and structural transitions across the ribbon thickness which are represented on a microstructure selection diagram for rapid solidification conditions. Although rapid solidification is known in many cases to produce metastable phases, in this case the equilibrium eutectic mixtures of Zn-Mg₂Zn₁₁ are observed after rapid solidification, whereas the metastable eutectic mixture Zn-MgZn₂ forms under normal solidification conditions. However, in the melt-spun Zn-Mg alloy which is exactly at eutectic composition, three different structures are observed across the ribbon thickness. These three structures do not exist simultaneously in the same region, but structural transitions occur as the thickness increases from the wheel side to the free side. Eutectic and hypereutectic alloys show a tendency to form a metallic glass. In these alloys a critical growth velocity exists beyond which eutectic solidification is not possible, suggesting a possible transition from eutectic solidification to amorphous phase formation. The eutectic phase selection and the extent to which a specific microstructure is present depends on the variation in growth rate and solid-liquid interface stability during rapid solidification.[/p]     

Prevalence of renal stones in a population-based study with dietary calcium, oxalate, and medication exposures

Little is known about the epidemiology of renal stones, in spite of the relative frequency of this painful condition. This population-based study examined reported renal stone diagnosis in 1,309 women aged 20-92 years to determine whether renal stones are associated with 1) food or water exposures or 2) lower bone mineral density and an increased likelihood of fractures. Results indicated a renal stone prevalence of 3.4%. The average age at diagnosis was 42 years. Renal stone formation was not associated with community of residence, hypertension, bone mineral density, fractures, high-oxalate food consumption, or ascorbic acid from food supplements. Women with renal stones consumed almost 250 mg/day less dietary calcium (p < 0.01) than did women without stones and had a lower energy intake (p < 0.04). The authors' findings do not support the hypothesis that increased dietary calcium is associated with a greater prevalence of renal stones, nor do they identify renal stones as a risk factor for low bone mineral density. Furthermore, lack of other identifiable environmental correlates and the relatively young age at initial diagnosis suggest that genetic components of renal stone formation need further study.     

Cuticle chirality and body handedness in Caenorhabditis elegans

BACKGROUND AND PURPOSE: Norway has the highest reported incidence of hip fractures in western Europe. Little is known about the epidemiology of falls in Norway where the winter season is long and dark. The objective of this work was to study reported falls and their consequences among elderly Norwegians living at home. METHODS: A cross-sectional design was used for the study. Interviews were performed in the homes of 431 subjects, aged 67-97 years, living at home. Information on falling was gathered through six questions: whether the subject had fallen during the last six months, and if so, how many falls they had, where the last fall occurred, its perceived reason, the activity the subject had been engaged in when the fall occurred, and the resulting injury. RESULTS: In all, 24.1% of subjects reported falling during the last six months, and 9.5% had suffered more than one fall. Falls were most frequently linked to external events (63.1%). Outdoor falls were more frequent (59.0%; 95% CI = 51.2-82.0) than indoor falls. Older subjects were associated with more frequent indoor falls (p < 0.05), but gender was not significant. Fifty-one per cent of subjects had fallen while walking and 53% had suffered an injury from the last fall. In 13.4% of the women and 16.2% of the men, the last fall had resulted in a fracture. CONCLUSIONS: Compared to the results of other studies from industrialized Western countries, a similar crude fall rate, similar frequency and similar type of injury were found. However, in contrast to other studies, no gender difference was observed with regard to falling, place of falling and fracture rate.     

Nightmare help: Treatment of trauma survivors with PTSD.

Describes strategies, techniques, and implementation of nightmare therapy for psychotherapy clients with posttraumatic stress disorder. Case examples of combat veteran trauma survivors are included. Approaches discussed include dream group, storyline alteration, story title conversion, sandplay, and face and conquer techniques. Based on a posttreatment survey administered to 25 clients, 65% of Ss reported the elimination of nightmares while the remaining 35% reported diminished distress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Impaired splenic function and tuftsin deficiency in patients with intestinal failure on long term intravenous nutrition

Relatively little is known about the occurrence of neurocysticercosis in northeastern Brazil. There have been no published reports from the state of Ceará, but a review of the records at the Hospital S?o José in Fortaleza, Brazil identified 119 patients with neurocysticercosis diagnosed between January 1988 and April 1994. Patients came from 43 municipalities in Ceará. Their ages ranged from five to 74 years; the greatest number of cases were in persons 10-40 years of age; 63% were males. Seizures were the presenting complaint in 64% of the patients and headache in 22%. Two patients, each with several hundred intracranial lesions, presented with mental status changes; one was initially given the clinical diagnosis of viral meningoencephalitis. Computed tomography scans showed that 44% of the patients had five or more lesions. Cysts were found throughout the brain. The parietal lobe was the most frequent site of involvement; 85% of patients had one or more lesions there. The brain stem was involved in 8%. There was no consistent association between the severity of the clinical abnormalities and the radiologic findings. Computed tomography of the thighs was done in 10 persons; cysts were identified in nine.     

Investigation of GaAs Schottky barrier diodes in the THz range

The properties of GaAs Schottky barrier diodes as video detectors and mixing elements were investigated in the frequency range from 0.8–2.5 THz. For the most sensitive diode, the video responsivity and system noise temperature were measured as a function of incident laser power. The highest video responsivity was 2,000 V/W at 214μm and 60 V/W at 118μm. For five diodes differing in doping, capacitance, series resistance and anode diameter, the system noise temperature was measured at 214μm and 118μm. The best single sideband (SSB) values are 12,300 K and 24,200 K at 214μm and 118μm, respectively. The system noise temperature versus frequency is given over the range from 0.5–3 THz for two specific diodes demonstrating that the sharpness of the I–V characteristics is only of secondary importance for mixer perfomance at such high frequencies.     

Experimental evidence for mode shape influence on acceleration-induced frequency shifts in quartz resonators

Experimental results are presented to support the hypothesis that the shape and location of the active region of vibration in a thickness shear mode quartz resonator are the dominant factors in determining the acceleration sensitivity of the resonator. The shape and location of the mode in a real world resonator vary sufficiently from unit to unit (due to material and processing variations) that all other considerations are overwhelmed. It is shown experimentally that the mode shape and/or location can be trimmed with energy trapping by judicious addition or subtraction of mass to produce resonators with improved acceleration sensitivity.     

Manufacturing Bespoke Architecture

At the disposal of today??s architect is an evolving array of interoperable tools and processes that allow the fabrication of design propositions to be increasingly complex, non?Cstandard and adaptive. How are we equipped to deal with such a growing breadth of new potential, and how are the philosophies that underpin this potential being defined? This paper attempts to address what is something of a contemporary dilemma in architecture, as the constraints of industrial standardisation are relaxed. Have the roles of designers and makers changed in a way that we??ve not experienced before, and is a new approach to making architecture emerging?