Conjugate imagery in the automated reproduction of three dimensional coordinates from two dimensional coordinate data

The three-dimensional video analysis of human motion commonly utilises automated image processing and digitisation processes to produce real-time unidentified two-dimensional coordinate data of segmental markers. In what can be a time-consuming process the two-dimensional data are then identified and tracked to produce three-dimensional coordinates. This paper presents an approach to the automated reproduction of three-dimensional coordinates from two-dimensional coordinates data. Conjugate imaging techniques were utilised in the development of four criterion measures for determining the validity of conjugate (corresponding) image points. An algorithm based on the criterion measures was then developed for the automated reproduction of three dimensional coordinates from camera image coordinate data. The algorithm was tested with a 55 point marker system viewed in four video cameras (digitisation error approx. 0.2%, lab point separation > or = 6 cm). The success of the algorithm was dependent on the closeness of markers, the accuracy of the photogrammetric system, and the number of markers visible in two camera images. The present research has developed techniques based on conjugate imagery for the automated reproduction of three-dimensional coordinates from two-dimensional data, and provided a bases for further development of automated three-dimensional tracking.     

Anatomy and physiology of saccadic long-lead burst neurons recorded in the alert squirrel monkey. I. Descending projections from the mesencephalon

1. The intra-axonal recording and horseradish peroxidase injection technique together with spontaneous eye movement monitoring has been employed in alert behaving monkeys to study the discharge pattern and axonal projections of mesencephalic saccade-related long-lead burst neurons (LLBNs). 2. Most of the recovered axons (N = 21) belonged to two classes of neurons. The majority (N = 13) were identified as efferents of the superior colliculus and had circumscribed movement fields typical of collicular saccade-related burst neurons. This discharge pattern, their responses to electrical stimulation of one or both superior colliculi, and their morphological appearance identified them as members of the T class of tectal efferent neurons. 3. Axons of these T cells deployed terminal fields within several saccade-related brain stem areas including the nucleus reticularis tegmenti pontis, which projects to the cerebellum; the nucleus reticularis pontis oralis and caudalis, which contains excitatory premotor burst neurons; the nucleus raphe interpositus, which contains omnipause neurons; the nucleus paragigantocellularis, which contains inhibitory premotor burst neurons, as well as other less differentiated parts of the brain stem reticular formation. 4. The other class of LLBNs (N = 4) had their somata in the medullary reticular formation just lateral to the interstitial nucleus of Cajal. They projected primarily to the raphe nuclei, the medullary reticular formation, and the paramedian reticular nucleus. Discharges were of the directional type with up ON directions (N = 3) and down ON directions (N = 1). 5. Other fibers, which project to pontine and medullary oculomotor structures but whose somata were not recovered (N = 4), illustrate that there are also other types of LLBNs that contribute to the generation and control of saccadic eye movements. 6. Our findings complement previous data about the axonal trajectories of T-type superior colliculus efferents. They also demonstrate the existence of LLBNs located in the mesencephalic reticular formation and their target areas in the brain stem. Implications of these findings for current concepts of oculomotor control are discussed.     

Changes in the diagnosis and treatment of traumatic splenic rupture: a retrospective analysis of 99 consecutive cases

From January 1986 to January 1995, 99 consecutive cases with a ruptured spleen were analysed retrospectively. Diagnostic peritoneal lavage was replaced by abdominal ultrasound as a routine screening investigation in blunt abdominal trauma after 1991. An abdominal computed tomography scan carried out in stable circulatory conditions provided additional information in 80% of the cases. The choice of treatment was related to the extent of the splenic damage and associated injuries. Even in degree IV ruptures splenorrhaphy was carried out successfully in 38% (five out of 12). The Hospital Trauma Index-Injury Severity Score (HTI-ISS) was significantly lower (17.7; n = 43) in conservative treatment than in cases treated by splenorrhaphy (27.6; n = 25) or splenectomy (33.6; n = 31). Conservative treatment (n = 43) resulted in a secondary intervention in 19%, whereas primary splenorrhaphy (n = 25) failed once (4%). Clinical morbidity was 26%, with no significant differences between conservative treatment, splenorrhaphy and splenectomy. Early mortality (0-30 days post-trauma) reached 14%, and was related to extensive injuries in all cases. The mean HTI-ISS in patients with a fatal outcome was 50.5. Overall, 62% of the injured spleens were saved, with the rate of splenic preservation improving throughout the study period. A conservative policy was increasingly treatment of first choice in patients with stable circulatory parameters with major concomitant injuries.     

GENETIC PROGRAMMING TO PREDICT SKI-JUMP BUCKET SPILLWAY SCOUR

Researchers in the past had noticed that application of Artificial Neural Networks （ANN） in place of conventional statistics on the basis of data mining techniques predicts more accurate results in hydraulic predictions. Mostly these works pertained to applications of ANN. Recently, another tool of soft computing, namely, Genetic Programming （GP） has caught the attention of researchers in civil engineering computing. This article examines the usefulness of the GP based approach to predict the relative scour depth downstream of a common type of ski-jump bucket spillway. Actual field measurements were used to develop the GP model. The GP based estimations were found to be equally and more accurate than the ANN based ones, especially, when the underlying cause-effect relationship became more uncertain to model.     

Lipids in total parenteral nutrition solutions differentially modify lipids in piglet intestinal brush border and microsomal membranes

BACKGROUND: Fats in the diet modify the lipid composition and function of the intestinal brush border membrane (BBM) as well as the enterocyte microsomal membrane (EMM). METHODS: This study was undertaken in pigs to establish the effect of 3 weeks of total parenteral nutrition (TPN) on the fatty acids in the major phospholipids, (phosphatidylcholine [PC] and phosphatidylethenolamine [PE] in the jejunal and ileal BBM and EMM. RESULTS: In a comparison of 21-day-old milk-fed piglets and newborn animals, there were differences in the major fatty acids (palmitic, 16:0; stearic, 18:0; oleic, 18:1 omega 9, and linoleic acid, 18:2 omega 6) in PC and PE in BBM and EMM. Age-matched (3-week-old) animals fed a lipid-free glucose-containing TPN solution had different membrane fatty acids than did milk-fed piglets, or animals given a soybean oil-containing TPN solution for 21 days. Substituting fish oil or fish oil plus soybean oil altered BBM and EMM fatty acids, compared with the soybean oil-based TPN solutions. These changes varied between the class of phospholipids (PC vs PE), between intestinal site (jejunum vs ileum), and between the type of membrane (BBM vs EMM). CONCLUSIONS: The jejunum and ileum have distinctive control mechanisms for varying their membrane lipids in response to TPN. There is some postmicrosomal modification of lipids between the EMM and BBM. It remains to be established whether the lipid content of the membranes of other organs, and therefore their function, is modified by the lipid composition of parenterally infused lipids.     

A mutation of the yeast gene encoding PCNA destabilizes both microsatellite and minisatellite DNA sequences

The POL30 gene of the yeast Saccharomyces cerevisiae encodes the proliferating cell nuclear antigen (PCNA), a protein required for processive DNA synthesis by DNA polymerase delta and epsilon. We examined the effects of the pol30-52 mutation on the stability of microsatellite (1- to 8-bp repeat units) and minisatellite (20-bp repeat units) DNA sequences. It had previously been shown that this mutation destabilizes dinucleotide repeats 150-fold and that this effect is primarily due to defects in DNA mismatch repair. From our analysis of the effects of pol30-52 on classes of repetitive DNA with longer repeat unit lengths, we conclude that this mutation may also elevate the rate of DNA polymerase slippage. The effect of pol30-52 on tracts of repetitive DNA with large repeat unit lengths was similar, but not identical, to that observed previously for pol3-t, a temperature-sensitive mutation affecting DNA polymerase delta. Strains with both pol30-52 and pol3-t mutations grew extremely slowly and had minisatellite mutation rates considerably greater than those observed in either single mutant strain.     

Managing sexually transmitted diseases in adolescents

Control of sexually transmitted diseases (STDs) in adolescents is a primary responsibility of health care providers. Using the tools of history and physical examination, and drawing on the awareness of different stages of adolescent development, health care providers can define at-risk for STDs. This article discusses screening practices, disease control through reporting and preventive counseling, and treatment guidelines for common STD syndromes.