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The reliance on vision to control a myoelectric prosthesis is cognitively burdensome and contributes to device abandonment. The feeling of uncertainty when gripping an object is thought to be the cause of this overreliance on vision in hand-related actions. We explored if experimentally reducing grip uncertainty alters the visuomotor control and mental workload experienced during initial prosthesis use. In a repeated measures design, twenty-one able-bodied participants took part in a pouring task across three conditions: (a) using their anatomical hand, (b) using a myoelectric prosthetic hand simulator, and (c) using a myoelectric prosthetic hand simulator with Velcro attached to reduce grip uncertainty. Performance, gaze behaviour (using mobile eye-tracking) and self-reported mental workload, was measured. Results showed that using a prosthesis (with or without Velcro) slowed task performance, impaired typical eye-hand coordination and increased mental workload compared to anatomic hand control. However, when using the prosthesis with Velcro, participants displayed better prosthesis control, more effective eye-hand coordination and reduced mental workload compared to when using the prosthesis without Velcro. These positive results indicate that reducing grip uncertainty could be a useful tool for encouraging more effective prosthesis control strategies in the early stages of prosthetic hand learning. [ABSTRACT FROM AUTHOR]

Mental chronometry has often been used to provide a temporal comparison between executed and imagined movements, with smaller discrepancies indicating more accurate image production and better imagery performance. In this study, we examined the importance of retinal and extra-retinal information in the performance of simple, sequential movements. After physical practice of four activities of daily living (Southampton Hand Assessment Procedure), nineteen participants imagined completing the same tasks with: 1) free eye-movements and visible objects, 2) free eye-movements and no visibility of the objects, and 3) constrained eye-movements and visible objects. Results suggested imagery performance was slower/less accurate compared to physical execution when the eyes were constrained. Conversely, chronometric imagery performance was unaffected with free eye movements, even when task-specific visual information was occluded. This study highlights the crucial role that eye-movements play in the regulation of the temporal aspects of imagery even when retinal information is absent, suggesting that temporal sequencing of imagined actions is largely dependent on extra-retinal information sources. [ABSTRACT FROM AUTHOR]

The oldest old (aged ≥80 years) are often the population subgroup at high nutritional risk due to age-related metabolic changes. We performed a validation analysis of a dietary screening tool (DST) which was developed for older adults among the oldest old. We examined dietary intakes using three 24-hour dietary recalls and the DST among 122 participants (aged 82–97) of the Geisinger Rural Aging Study. DST scores were compared with the Health Eating Index (HEI)-2015 scores, which were calculated based on three-day dietary recalls. Pearson correlations were used to characterize concurrent validity and Bland-Altman plots were used to identify potential bias. DST scores were significantly correlated with HEI scores (adjusted r = 0.68; p < 0.001) in an age- and sex-adjusted model. Those within the not-at-risk DST group had significantly higher HEI scores (adjusted means = 79.6 ± 3.68) compared with those who were in the at-risk (adjusted means = 51.2 ± 1.56) and the possibly-at-risk (adjusted means = 66.3 ± 1.79) groups (p-trend < 0.001). The DST appears to be a valid measure of diet quality in the oldest old when compared with the HEI and may be a potential tool to assess overall diet quality in this population. [ABSTRACT FROM AUTHOR]

The aim of this study was to provide a detailed account of the spatial and temporal disruptions to eye-hand coordination when using a prosthetic hand during a sequential fine motor skill. Twenty-one able-bodied participants performed 15 trials of the picking up coins task derived from the Southampton Hand Assessment Procedure with their anatomic hand and with a prosthesis simulator while wearing eye-tracking equipment. Gaze behavior results revealed that when using the prosthesis, performance detriments were accompanied by significantly greater hand-focused gaze and a significantly longer time to disengage gaze from manipulations to plan upcoming movements. The study findings highlight key metrics that distinguish disruptions to eye-hand coordination that may have implications for the training of prosthesis use. [ABSTRACT FROM AUTHOR]

The advent of chemical abrasion-isotope dilution thermal ionisation mass spectrometry (CA-IDTIMS) has revolutionised U–Pb dating of zircon, and the enhanced precision of eruption ages determined on volcanic layers within basin successions permits an improved calibration of biostratigraphic schemes to the numerical time-scale. The Guadalupian and Lopingian (Permian) successions in the Sydney, Gunnedah, Bowen and Canning basins are mostly non-marine and include numerous airfall tuff units, many of which contain zircon. The eastern Australian palynostratigraphic scheme provides the basis for much of the local correlation, but the present calibration of this scheme against the numerical time-scale depends on a correlation to Western Australia, using rare ammonoids and conodonts in that succession to link to the standard global marine biostratigraphic scheme. High-precision U–Pb zircon dating of tuff layers via CA-IDTIMS allows this tenuous correlation to be circumvented—the resulting direct calibration of the palynostratigraphy to the numerical time-scale highlights significant inaccuracies in the previous indirect correlation. The new data show: the top of thePraecolpatites sinuosusZone (APP3.2) lies in the early Roadian, not the middle Kungurian; the top of theMicrobaculispora villosaZone (APP3.3) lies in the middle Roadian, not the early Roadian; the top of theDulhuntyispora granulataZone (APP4.1) lies in the Wordian, not in the latest Roadian; the top of theDidecitriletes ericianusZone (APP4.2) lies in the first half of the Wuchiapingian, not the latest Wordian; theDulhuntyispora dulhuntyiZone (APP4.3) is exceptionally short and lies within the Wuchiapingian, not the early Capitanian; and the top of theDulhuntyispora parvitholaZone (APP5) lies at or near the Permo-Triassic boundary, not in the latest Wuchiapingian. [ABSTRACT FROM PUBLISHER]

Little is known about the relationship between weight change and dietary patterns (DP) in older adults, especially in those of advanced age (≥75 years). We examined the association of DP with obesity and five-year weight change in community-dwelling older adults (n = 270; mean ± SD age: 78.6 ± 3.9 years). Dietary data were collected from four, random, 24-hour dietary recalls over a 10-month period. Weight change was examined as: (1) 10-pound weight loss; (2) 10-pound weight gain; (3) 10% weight loss; and (4) 10% weight gain. Cluster analysis was used to derive 3 DP (“Health-conscious,” “Sweets and dairy,” and “Western”). Kaplan-Meier plots and Cox proportional hazards regression models were used. About 39% of participants lost at least 10 pounds during follow up. In the unadjusted model, five-year weight loss was not associated with dietary pattern. However, when stratified by gender, females who were characterized by the Sweets and Dairy and the Western DP were three and two times more likely to lose 10 pounds, respectively, compared to those in the Health-conscious DP (P < 0.05). These observations suggest that it is appropriate to recommend a Health-conscious DP for women 75 years and older who may be at risk for weight loss. [ABSTRACT FROM PUBLISHER]

Marine nitrogen (N) has been traced into terrestrial and freshwater food chains at petrel (Aves: Procellariiformes) colonies on the South Island of New Zealand, but the effects of N or other marine-derived nutrients on the productivity of mainland forests are unknown. Mean ring widths in matai (Prumnopitys taxifolia; n = 3) and rimu (Dacrydium cupressinum; n = 2) trees growing in a Westland petrel (Procellaria westlandica) colony were 0.9-1.4 mm yr-1, similar to ring widths reported elsewhere. However, series of much wider rings in cores showed that trees in a petrel colony can experience periods of accelerated growth. δ15N values of whole wood were, at 3.2-11.1‰, significantly enriched in comparison to other temperate forest trees. The highest δ15N values were at the cambial and pith ends of different cores, so isotopic fractionation during N remobilisation is unlikely to have been significant. The radial extent of 15N enrichment suggests that petrels have bred at the site since at least the mid 18th century. [ABSTRACT FROM AUTHOR]

This article analyses a counting process associated with a stochastic process arising in global optimisation. Backtracking adaptive search (BAS) is a theoretical stochastic global optimisation algorithm modelling the temporary acceptance of solutions of lower quality. BAS generalises the pure adaptive search and hesitant adaptive search algorithms, whose full search duration distributions are known. This article gives the exact expected search duration for backtracking adaptive search. [ABSTRACT FROM AUTHOR]

Alveolar procalcitonin (PCT) concentrations may be a useful aid in the diagnosis of ventilator-associated pneumonia (VAP). To better characterize the potential utility of PCT in VAP, this study evaluated the relationship between serum and alveolar PCT concentrations in twelve critically ill trauma patients. Furthermore, the relationship between alveolar PCT concentrations, pneumonia development, and alveolar proinflammatory cytokine concentrations were analyzed. Serum and alveolar fluid were collected simultaneously within 48 hours of admission and at 4-7 days post-admission for analyte analysis. Overall, there was no significant correlation between serum and alveolar PCT concentrations. In six patients who developed VAP, alveolar PCT did not increase. Changes in alveolar PCT concentrations from baseline to follow-up were inversely related to changes in alveolar TNF-α and IL-1ß. The results of this study suggest that PCT production is compartmentalized within the lung, similar to proinflammatory cytokines. More studies are needed to define the potential role of alveolar PCT in the diagnosis and pathogenesis of pneumonia. [ABSTRACT FROM PUBLISHER]

Testing goodness of fit for a Poisson distribution is routine when the mean is sufficiently large; the scaled deviance G² or Pearson's X² statistic follow approximate chi-square distributions and perform the task well. When the mean is low, typically less than one, the approximations to chi-square distributions are poor. In this paper we explore the underlying reasons for this behaviour and present a practical resolution of the problem, in both single distribution and regression contexts. An extension to negative binomial models is also given. This research is motivated by a real example drawn from road accident modelling. [ABSTRACT FROM AUTHOR]

The pharmacokinetics and pharmacodynamics (T > MIC) of ceftazidime in the plasma and pulmonary epithelial lining fluid (ELF) were compared following intermittent (IC) and continuous ceftazidime (CC) infusion (60 mg/kg/d) in nine crossbred male intact pigs. The ceftazidime plasma half-life, volume of distribution, clearance, and area under the plasma concentration-time curve were similar between the IC and CC regimens. Ceftazidime area under the ELF concentration-time curve were 29.6% and 23.4% of the area under the plasma concentration- time curve for the IC and CC regimens, respectively. The ceftazidime half-life in the ELF was approximately two-fold longer compared to the plasma half-life. This suggests that the penetration of ceftazidime into the ELF is membrane-limited and may not display compartmental pharmacokinetic characteristics. Using T > MIC as a surrogate marker of efficacy, ceftazidime's limited ELF penetration may hinder pharmacodynamic optimization against less susceptible gram-negative bacteria causing pneumonia. [ABSTRACT FROM PUBLISHER]

Barrier-type anodic oxide films, with relatively uniform distributions of Al[sup 3+] and Zr[sup 4+] ions, have been formed on sputter-deposited, non-equilibrium Zr-Al alloys, containing 5, 15 and 43 at.% Al, in 0.01M ammonium pentaborate electrolyte at 293K. The films formed on the last two alloys are primarily amorphous, with transport numbers of cations of about 0.18 and 0.25 respectively, i.e., increasing with increase in aluminium content. Thus, as for other amorphous anodic oxides, both cation and anion transport contribute significantly to film growth. However, nanocrystals, suggested to be based on cubic ZrO[sub 2], are formed near the alloy-film interface in the amorphous oxide matrix, in association with bubbles due to generation of oxygen gas in the vicinity of the alloy-film interface. Increase in the zirconium content to 95 at.% leads to the formation of a relatively uniform, crystalline anodic film with a monoclinic ZrO[sub 2] structure; film growth now proceeds predominantly due to migration of anions, similar to films formed on high purity zirconium. [ABSTRACT FROM AUTHOR]

SUMMARY For the past 20 years, forest modellers have largely used the Weibull distribution to summarize diameter distributions and to predict timber volume in a forest at clearfell time. The wider family of Burr distributions is investigated here as an alternative to the Weibull distribution. Using data from 20 permanent sample plots of Pinus radiata, we compare Burr and Weibull fits, showing that the Burr distribution enhances precision by roughly 13 . The effectiveness of the Burr distribution for prediction is found to be similar to that of the Weibull distribution. [ABSTRACT FROM AUTHOR]

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The section of "Wool-Scouring" focuses on various methods of scouring waste-water disposal. The methods have been classified into three categories, including biological and physico-chemical methods. Information on large-area biological-treatment plant, aerobic treatments, and anaerobic digestion is also given. Flocculation of liquors by means of inorganic or polymeric flocculants has been the basis of many industrial plants. Physical methods include membrane processes, solvent extraction, and evaporation.

A Lo-flo run with high-yielding merino-fleece wool gave a mass balance that was good for solvent-extractables and dirt but poor for water-solubles. The discrepancy is attributed to failure of the water-solubles to reach steady-state concentrations in the bowls, itself a result of the very low countercurrent flow. Some 88% of the grease originally present on the wool was removed in the centrifuges, but dirt removal (50%) was only moderate. Indirect evidence indicates that the dirt fraction not removed was mainly organic material forming complexes with oxidized grease. [ABSTRACT FROM AUTHOR]

An investigation is described in which the scouring of merino crutchings in a Lo-flo machine gave a grease recovery of 75% in the cream, and centrifugal sludges were characterized by a high grease content. The scouring efficiency of the Lo-flo unit was 84% for grease and 58% for din. Steady-state conditions for the first four bowls are reported, A water consumption of 6.4 L/kg in Ihe rinse bowls and 1.9 L/kg from bowl 4 may not have been sufficient to maintain acceptable conditions in the rinse bowls in very long runs. [ABSTRACT FROM AUTHOR]

An investigation is reported in which a pilot-scale Lo-flo scouring machine was used to scour a 9665-kg lot of crossbred fleece wool wiih no liquor discharge other than the rinse water. Scouring and centrifuging efficiencies and the quantities and compositions of all centrifuge streams are reported. Removal of contaminants by the centrifuges was: grease 88%; water-solubles 54%: dirt 27%. The steady-state concentration of water-solubles in the first bowl was 34,7% w/w. [ABSTRACT FROM AUTHOR]

In a 2 × 2 factorial design, 32 hunger-motivated albino rats were trained to press a bar for food in a Skinner box. Animals practiced this operant, with or without a mere-presence conspecific, on a VR reinforcement schedule for 10 days and were extinguished with or without a conspecific in a nearby compartment. The results showed that the presence of a conspecific did not enhance this operant during practice sessions nor its resistance to extinction. During extinction the animals that experienced the presence or absence of a conspecific for the first time showed a reduced rate of responding. The findings cast doubt on a drive theory of social facilitation and support a generalization-decrement hypothesis. [ABSTRACT FROM AUTHOR]