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The Unilateral Below Elbow Test (UBET) was developed to evaluate function in bimanual activities for both the prosthesis wearer and non-wearer. Nine tasks were chosen for each of four age-specific categories defined by development stages of hand function (2–4y, 5–7y, 8–10y, and 11–21y). Two scales, Completion of Task and Method of Use, were designed to rate performance. To measure reliability, four occupational therapists scored samples of videotaped UBET performances. For Completion of Task, an interval scale, agreement in scoring was measured with interclass correlation coefficients (ICC; n=9; five females, four males). For Method of Use, a nominal scale, chance-adjusted association was calculated with Cohen's kappa coefficients (interobserver n=198; 111 females, 87 males; intraobserver n=93; 56 females, 37 males). For Completion of Task, the average ICC was 0.87 for the prosthesis-on condition, and 0.85 for the prosthesis-off condition. ICCs exceeded 0.80 for eight out of nine tasks for the two older age groups, but for only five out of nine tasks in the younger age groups. Higher inter- and intraobserver kappa coefficients for Method of Use resulted when scoring children with their prostheses on versus off. The oldest age group had lower kappa values than the other three groups. The UBET is recommended for the functional evaluation of Completion of Task in children with unilateral congenital below elbow deficiency with and without their prostheses. Method of Use scoring can evaluate individuals for directed therapy interventions or prosthetic training.
The relationships between different levels of severity of ambulatory cerebral palsy, defined by the Gross Motor Function Classification System (GMFCS), and several pediatric outcome instruments were examined. Data from the Gross Motor Function Measure (GMFM), Pediatric Orthopaedic Data Collection Instrument (PODCI), temporal–spatial gait parameters, and oxygen cost were collected from six sites. The sample size for each assessment tool ranged from 226 to 1047 participants. There were significant differences among GMFCS levels I, II, and III for many of the outcome tools assessed in this study. Strong correlations were seen between GMFCS level and each of the GMFM sections D and E scores, the PODCI measures of Transfer and Mobility, and Sports and Physical Function, Gait Velocity, and Oxygen Cost. Correlations among tools demonstrated that the GMFM sections D and E scores correlated with the largest number of other tools. Logistic regression showed GMFM section E score to be a significant predictor of GMFCS level. GMFM section E score can be used to predict GMFCS level relatively accurately (76.6%). Study data indicate that the assessed outcome tools can distinguish between children with different GMFCS levels. This study establishes justification for using the GMFCS as a classification system in clinical studies.
The scavenging megafauna of the South Georgia and Shag Rocks slope in the south-west Atlantic (625–1519 m) were investigated using autonomous baited camera systems. Two surveys were conducted: the first in 1997 (13 deployments) used a conventional 35 mm stills camera with a 200 J flash, whilst the second in 2000 (15 deployments) used low-light digital video cameras. The scavenging community responded rapidly to the arrival of bait on the sea floor and was dominated by stone crabs (Lithodidae) and toothfish (Dissostichus eleginoides). Stone crabs took up residence around the bait until it was consumed, with a maximum number of 108 in the field of view after four hours. The most frequently observed crab species was Paralomis formosa. Paralomis spinosissima, Neolithodes diomedea and Lithodes sp., were also observed. Toothfish were the most frequently observed scavenging fish and were seen during all but one deployment, typically making brief visits (1–2 min) to the bait, but appeared startled by the flash in the 1997 survey. Labriform swimming (sculling with the pectoral fins) was the principal form of locomotion in toothfish (0.22 body lengths (BL) sec−1), but they were capable of more rapid sub-carangiform (using caudal trunk and fin) motion (3 BL sec−1) when startled. Other scavenging fish observed included the blue-hake Antimora rostrata, grenadiers (Macrourus spp.), skates, liparids and zoarcids.
The scavenging fauna of the Patagonian slope (900–1750 m), east of the Falkland Islands was investigated using the Aberdeen University Deep Ocean Submersible (AUDOS), an autonomous baited camera vehicle designed to photograph scavenging fish and invertebrates. The AUDOS was deployed on ten occasions in Falkland waters. Nine experiments were of 10–14 h duration and baited with 800 g of squid and one experiment lasted six days, baited with a 10 kg toothfish (Dissostichus eleginoides). Analysis of photographs revealed considerable patchiness in the composition of the scavenging fauna. Hagfish (Myxine cf. fernholmi) dominated three of the shallower experiments including the 6-d experiment, arriving quickly from down-current, holding station at the bait and consuming the soft tissues first, with consumption rates of up to 200 g h−1. In the other experiments, stone crabs (Lithodidae), the blue-hake (Antimora rostrata) and amphipods were the primary consumers, but the rate of bait consumption was lower. Patagonian toothfish (D. eleginoides) were attracted to the bait at each experiment, but did not attempt to consume the bait. The patchiness in the fauna may be a result of depth, substratum and topography, but in general the rapid response of the scavenging fauna indicates that carrion is rapidly dispersed, with little impact on the local sediment community.
The retinal vasculature of postmortem normal human and diabetic
eyes was studied using an
immunohistochemical technique in conjunction with confocal laser scanning
microscopy. The technique,
which stained for von Willebrand factor, allowed both large areas of the
retinal vasculature to be visualised
and abnormalities to be studied in detail without disturbing the tissue
architecture. Only one
microaneurysm, defined as any focal capillary dilation, was observed in
10 normal eyes but numerous
microaneurysms were seen in 4 out of 5 diabetic retinas; counts varied
between 0 and 26 per 0.41 mm2
sample area. Microaneurysms were classified into 3 categories according
to morphology: saccular, fusiform
and focal bulges. Most were saccular, these having no preferred orientation.
The majority of
microaneurysms were associated with just 2 vessels suggesting they were
unlikely to develop at vascular
junctions. The majority were observed to originate from the inner nuclear
layer and were therefore in the
deeper part of the inner retinal capillary plexus. Variation in the staining
of microaneurysms may correlate
with endothelial dysfunction seen clinically as dye leakage during fluorescein
The Code Activated Transponder (CAT) ingestible fish tag capable of operating at depths of 6 000 m is described. The CAT is acoustically interrogated by a scanning sonar
mounted on the AUDOS free-fall camera lander vehicle. The CAT, 12.5 mm diameter and 65 mm long works at ultrasonic frequencies (77 KHz) and can be tracked to a range of 500 m. The
AUDOS lander incorporates the new TRATEX (Transponding Acoustic Tracking Experiment) system that logs direction and range of individually tagged fish together with current and compass information. Typical results are shown from a track of 3 Coryphaenoides (Nematonurus) armatus (Macrouridae) taken at the Porcupine Seabight in the North Atlantic (49° 35'N-13° 43'W), 3 500 m deep. The mean fish swimming speed was 0.087 m.s−1. Despite their low speed, fish moved independently of the bottom current, either cross-current or against the current, optimising the chance of encountering odour plumes from new food falls.
The Growth of the illegal, psychoactive drug industry has had a dramatic impact on Colombia. Most studies of the financial effects of this industry — mainly cocaine and its by products, but extending also to marijuana, quaaludes, other psychoactive substances, and, more recently, heroin — have focussed upon trying to estimate its size and determining its impact on the national economy. On the whole, the conclusion of most observers has been that its effects on the latter have been more negative that positive (Kalmanovitz, 1989; Reyes, 1990; Sarmiento, 1990; Urrutia, 1990; Thoumi, 1987).
The Flow of drugs from Mexico to the United States has been a source of trouble in US-Mexican relations for at least two decades. The dominant view in Mexico is that the problem arises from the inability of the United States to control its domestic demand for heroin, cocaine, and marijuana. The dominant US view has been that the Mexican government has failed to make effective efforts to control the supply of drugs. At times — in particular after the killing of Enrique Camarena, an agent of the Drug Enforcement Administration (DEA), in 1985 — US government anger at Mexico's alleged failure to maintain the integrity of its anti-drug efforts has been the dominant source of friction between the two nations.
In September 1989, President Bush outlined a comprehensive, multi-faceted drug control strategy with both national and international dimensions. The strategy focused on reducing both the demand and supply of illicit drugs. Treatment, prevention/education, research, law enforcement, and international efforts are major components of the strategy. An important goal of the strategy was to reduce the amount of illicit drugs illegally entering the United States by 15% within 2 years and by 60% within 10 years. The president refined the strategy and forwarded it to Congress on 25 January 1990 (US-ONDCP, 1990: 49-52, 120-121). The following year, in February 1991, policymakers modified goals to a 20% reduction by 1993 and a 65% reduction by the year 2001 (US-ONDCP, 1991: 15).
In an Effort to extend and accelerate regional cooperation and coordination in the “War on Drugs” in the Western Hemisphere, President George Bush hosted a widelypublicized, regional, anti-drug presidential summit in San Antonio (Texas) on 26-27 February 1992. This cumbre was conceived as an expanded sequel to the first “Andean” drug summit held in Cartagena (Colombia) on 15 February 1990. In addition to the original four-country participants in Cartagena I — the United States, Colombia, Peru, and Bolivia — Ecuador, Venezuela, and Mexico attended Cartagena II as well.
Paraguay and its closest neighbors, the Rio Plata Basin from one point of view or the Southern Cone from another, have experienced an increasing challenge from the drug traffic in recent years. Initially, everything linked to drug use and traffic was considered—in general, much oversimplified terms — mainly as the social problem of a rich society, primarily that of the United States. The South American countries, preoccupied with surviving the blows of the “lost decade” while trying, simultaneously, both to throw off authoritarian regimes in terminal crisis and to negotiate transitions from democracy, assumed this problem could not affect them. In any event, that aspect of the drug trade which concerned the countries of South America above all was the growing tragedy of Colombia, which was just beginning to make headlines in the world press.
In Just 20 Years Peru has shifted from beacon of hope to basket case. As late as the mid-1970s, Peru's reformist military government (1968-1980) appeared to offer significant possibilities for economic and political development (defined as improved distribution of income and greater participation by the citizenry). From 1940 to 1975, economic growth and low inflation had been the norm. A major agrarian reform during the military docenio (12-year rule) created production cooperatives nation wide; the industrial community gave workers a meaningful management role in the operation of their firms. Both stirred the imagination of many Peruvians and the academic community alike.
Silicon nitride films deposited from silane-nitrogen and silane-ammonia mixtures by PECVD contain large amounts of hydrogen. We have determined that adding argon to the gas mixture reduces the amount of hydrogen in the resulting films. Differences in film composition are obviously due to changes in the chemistry of the discharge which was characterized by line-of-sight mass spectrometry, optical emission spectroscopy and plasma double probe measurements. Substrate temperature was fixed at 325°C, pressure was 500 mtorr, the RF power was 0.25 watts cm−2, the silane to nitrogen ratio was varied from 0.003 to 0.02, the silane to ammonia ratio was varied from 0.01 to 0.5, and the argon additions were 10% of the total gas flow. Argon additions to the discharge increased the plasma density in both nitrogen and ammonia plasmas. Optical emission from N2 and Si-H species increased upon the addition of 10% argon to the silane-nitrogen discharge, whereas the N-H emission decreased upon addition of argon to the silane-ammonia discharge. Infrared transmission spectra of films deposited with and without argon show no change in peak position or intensity of Si-H and N-H absorption bands in the spectral range studied, despite a large (over 20%) reduction in hydrogen content, as determined by nuclear profiling, upon the addition of argon. These results suggest that a substantial fraction of the hydrogen in the films is not infrared active. We propose that the reduction in hydrogen content is due to bombardment of the growing film by argon ions, which sputter the adsorbed hydrogen molecules.
Oxide compounds have been extensively studied through the years because they exhibit a broad spectrum of electrical, magnetic, and optical properties providing both scientific and technological interest. Most oxides are insulators, but a few of them (e.g., LiTi2O4 or BaPb1−x BixO3 show metallic conductivity and even superconductivity at low temperatures. The discovery of superconductivity at 35 K by Bednorz and Müller in the cuprate La-Ba-Cu-O system prompted the search for other high Tc compounds among this oxide family. Superconductivity above liquid nitrogen was then rapidly achieved with the Y-Ba-Cu-O system (Tc=90 K) and subsequently, with the Bi-Sr-Ca-Bu-O and Tl-Ba-Ca-Cu-O systems, Tc was raised to 110 K and then 125 K.
A common feature of these new high Tc cuprates is that they belong to the large family of materials, termed perovskites, which have been studied over the years because of their ability to absorb or lose oxygen reversibly (i.e., for their nonstoichiometry in oxygen). It had been previously established in the field of superconductivity that Tc is extremely sensitive to compositional stoichiometry.