940 resultados para indirect quantification


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Intramedullary nailing is the standard fixation method for displaced diaphyseal fractures of tibia. Selection of the correct nail insertion point is important for axial alignment of bone fragments and to avoid iatrogenic fractures. However, the standard entry point (SEP) may not always optimise the bone-nail fit due to geometric variations of bones. This study aimed to investigate the optimal entry for a given bone-nail pair using the fit quantification software tool previously developed by the authors. The misfit was quantified for 20 bones with two nail designs (ETN and ETN-Proximal Bend) related to the SEP and 5 entry points which were 5 mm and 10 mm away from the SEP. The SEP was the optimal entry point for 50% of the bones used. For the remaining bones, the optimal entry point was located 5 mm away from the SEP, which improved the overall fit by 40% on average. However, entry points 10 mm away from the SEP doubled the misfit. The optimised bone-nail fit can be achieved through the SEP and within the range of a 5 mm radius, except posteriorly. The study results suggest that the optimal entry point should be selected by considering the fit during insertion and not only at the final position.

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Reported homocysteine (HCY) concentrations in human serum show poor concordance amongst laboratories due to endogenous HCY in the matrices used for assay calibrators and QCs. Hence, we have developed a fully validated LC–MS/MS method for measurement of HCY concentrations in human serum samples that addresses this issue by minimising matrix effects. We used small volumes (20 μL) of 2% Bovine Serum Albumin (BSA) as surrogate matrix for making calibrators and QCs with concentrations adjusted for the endogenous HCY concentration in the surrogate matrix using the method of standard additions. To aliquots (20 μL) of human serum samples, calibrators or QCs, were added HCY-d4 (internal standard) and tris-(2-carboxyethyl) phosphine hydrochloride (TCEP) as reducing agent. After protein precipitation, diluted supernatants were injected into the LC–MS/MS. Calibration curves were linear; QCs were accurate (5.6% deviation from nominal), precise (CV% ≤ 9.6%), stable for four freeze–thaw cycles, and when stored at room temperature for 5 h or at −80 °C (27 days). Recoveries from QCs in surrogate matrix or pooled human serum were 91.9 and 95.9%, respectively. There was no matrix effect using 6 different individual serum samples including one that was haemolysed. Our LC–MS/MS method has satisfied all of the validation criteria of the 2012 EMA guideline.

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During Pavlovian auditory fear conditioning a previously neutral auditory stimulus (CS) gains emotional significance through pairing with a noxious unconditioned stimulus (US). These associations are believed to be formed by way of plasticity at auditory input synapses on principal neurons in the lateral nucleus of the amygdala (LA). In order to begin to understand how fear memories are stored and processed by synaptic changes in the LA, we have quantified both the entire neural number and the sub-cellular structure of LA principal neurons.We first used stereological cell counting methods on Gimsa or GABA immunostained rat brain. We identified 60,322+/-1408 neurons in the LA unilaterally (n=7). Of these 16,917+/-471 were GABA positive. The intercalated nuclei were excluded from the counts and thus GABA cells are believed to represent GABAergic interneurons. The sub-nuclei of the LA were also independently counted. We then quantified the morphometric properties of in vitro electrophysiologically identified principal neurons of the LA, corrected for shrinkage in xyz planes. The total dendritic length was 9.97+/-2.57mm, with 21+/-4 nodes (n=6). Dendritic spine density was 0.19+/-0.03 spines/um (n=6). Intra-LA axon collaterals had a bouton density of 0.1+/-0.02 boutons/um (n=5). These data begin to reveal the finite cellular and sub-cellular processing capacity of the lateral amygdala, and should facilitate efforts to understand mechanisms of plasticity in LA.

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Background Assessing hand injury is of great interest given the level of involvement of the hand with the environment. Knowing different assessment systems and their limitations generates new perspectives. The integration of digital systems (accelerometry and electromyography) as a tool to supplement functional assessment allows the clinician to know more about the motor component and its relation to movement. Therefore, the purpose of this study was the kinematic and electromyography analysis during functional hand movements. Method Ten subjects carried out six functional movements (terminal pinch, termino-lateral pinch, tripod pinch, power grip, extension grip and ball grip). Muscle activity (hand and forearm) was measured in real time using electromyograms, acquired with the Mega ME 6000, whilst acceleration was measured using the AcceleGlove. Results Electrical activity and acceleration variables were recorded simultaneously during the carrying out of the functional movements. The acceleration outcome variables were the modular vectors of each finger of the hand and the palm. In the electromyography, the main variables were normalized by the mean and by the maximum muscle activity of the thenar region, hypothenar, first interosseous dorsal, wrist flexors, carpal flexors and wrist extensors. Conclusions Knowing muscle behavior allows the clinician to take a more direct approach in the treatment. Based on the results, the tripod grip shows greater kinetic activity and the middle finger is the most relevant in this regard. Ball grip involves most muscle activity, with the thenar region playing a fundamental role in hand activity. Clinical relevance Relating muscle activation, movements, individual load and displacement offers the possibility to proceed with rehabilitation by individual component.

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Summary This manual was developed to guide a move towards common standards for undertaking and reporting research microscopy for malaria parasite detection, identification and quantification. It contains procedures based on agreed quality assurance standards for research malaria microscopy defined at a consultation of: TDR, the Special Programme for Research and Training in Tropical Diseases; the Worldwide Antimalarial Resistance Network (WWARN), United Kingdom; the Foundation for Innovative New Diagnostics (FIND), Switzerland; the Centers for Disease Control and Prevention (CDC), USA; the Kenya Medical Research Institute (KEMRI) and later expanded to include Amref Health Africa (Kenya); the Eijkman-Oxford Clinical Research Unit (EOCRU), Indonesia; Institut Pasteur du Cambodge (IPC); Institut de recherche pour le Développement (IRD), Senegal; the Global Good and Intellectual Ventures Laboratory (GG-IVL), USA; the Mahidol-Oxford Tropical Medicine Research Unit (MORU), Thailand; Queensland University of Technology (QUT), Australia, and the Shoklo Malaria Research Unit (SMRU), Thailand. These collaborating institutions commit to adhering to these standards in published research studies. It is hoped that they will form a solid basis for the wider adoption of standardized reference microscopy protocols for malaria research.

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In Uganda, a significant proportion of the population depends on the micronutrient poor East African highland banana as a food staple. Consequently, micronutrient deficiencies such as vitamin A deficiency are an important health concern in the country. To reach most vulnerable rural poor populations, staple crops can be biofortified with essential micronutrients though conventional breeding or genetic engineering. This thesis provided proof of concept that genetically modified East African highland bananas with enhanced provitamin A levels can be generated and fully characterised in Uganda. In addition, provitamin A levels present in popular banana varieties was documented.

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Objective The aim of this study was to determine the linear acceleration, time-to-peak acceleration, and effect of hand position comparing 2 clinicians completing a thoracic manipulation. Methods Thirteen volunteers received a right- and left-“handed” prone thoracic manipulation while accelerations were recorded by an inertial sensor. Peak thrust acceleration and time-to-peak thrust were measured. Results There were differences in thrust acceleration between right- and left-handed techniques for one therapist. The mean peak thrust acceleration was different between therapists, with the more practiced therapist demonstrating greater peak thrust accelerations. Time-to-peak acceleration also revealed between therapist differences, with the more practiced therapist demonstrating shorter time-to-peak acceleration. Cavitation data suggested that manipulations with greater accelerations were more likely to result in cavitation. Conclusion The results of this study suggest that with greater frequency of use, therapists are likely to achieve greater accelerations and shorter time-to-peak accelerations. Furthermore, this study showed that an inertial sensor can be used to quantify important variables during thoracic manipulation and are able to detect intertherapist differences in technique.

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The microbial mediated production of nitrous oxide (N2O) and its reduction to dinitrogen (N2) via denitrification represents a loss of nitrogen (N) from fertilised agro-ecosystems to the atmosphere. Although denitrification has received great interest by biogeochemists in the last decades, the magnitude of N2lossesand related N2:N2O ratios from soils still are largely unknown due to methodical constraints. We present a novel 15N tracer approach, based on a previous developed tracer method to study denitrification in pure bacterial cultures which was modified for the use on soil incubations in a completely automated laboratory set up. The method uses a background air in the incubation vessels that is replaced with a helium-oxygen gas mixture with a 50-fold reduced N2 background (2 % v/v). This method allows for a direct and sensitive quantification of the N2 and N2O emissions from the soil with isotope-ratio mass spectrometry after 15N labelling of denitrification N substrates and minimises the sensitivity to the intrusion of atmospheric N2 at the same time. The incubation set up was used to determine the influence of different soil moisture levels on N2 and N2O emissions from a sub-tropical pasture soil in Queensland/Australia. The soil was labelled with an equivalent of 50 μg-N per gram dry soil by broadcast application of KNO3solution (4 at.% 15N) and incubated for 3 days at 80% and 100% water filled pore space (WFPS), respectively. The headspace of the incubation vessel was sampled automatically over 12hrs each day and 3 samples (0, 6, and 12 hrs after incubation start) of headspace gas analysed for N2 and N2O with an isotope-ratio mass spectrometer (DELTA V Plus, Thermo Fisher Scientific, Bremen, Germany(. In addition, the soil was analysed for 15N NO3- and NH4+ using the 15N diffusion method, which enabled us to obtain a complete N balance. The method proved to be highly sensitive for N2 and N2O emissions detecting N2O emissions ranging from 20 to 627 μN kg-1soil-1hr-1and N2 emissions ranging from 4.2 to 43 μN kg-1soil-1hr-1for the different treatments. The main end-product of denitrification was N2O for both water contents with N2 accounting for 9% and 13% of the total denitrification losses at 80% and 100%WFPS, respectively. Between 95-100% of the added 15N fertiliser could be recovered. Gross nitrification over the 3 days amounted to 8.6 μN g-1 soil-1 and 4.7 μN g-1 soil-1, denitrification to 4.1 μN g-1 soil-1 and 11.8 μN g-1 soil-1at 80% and 100%WFPS, respectively. The results confirm that the tested method allows for a direct and highly sensitive detection of N2 and N2O fluxes from soils and hence offers a sensitive tool to study denitrification and N turnover in terrestrial agro-ecosystems.

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This study implemented linear and nonlinear methods of measuring variability to determine differences in stability of two groups of skilled (n = 10) and unskilled (n = 10) participants performing 3m forward/backward shuttle agility drill. We also determined whether stability measures differed between the forward and backward segments of the drill. Finally, we sought to investigate whether local dynamic stability, measured using largest finite-time Lyapunov exponents, changed from distal to proximal lower extremity segments. Three-dimensional coordinates of five lower extremity markers data were recorded. Results revealed that the Lyapunov exponents were lower (P < 0.05) for skilled participants at all joint markers indicative of higher levels of local dynamic stability. Additionally, stability of motion did not differ between forward and backward segments of the drill (P > 0.05), signifying that almost the same control strategy was used in forward and backward directions by all participants, regardless of skill level. Furthermore, local dynamic stability increased from distal to proximal joints (P < 0.05) indicating that stability of proximal segments are prioritized by the neuromuscular control system. Finally, skilled participants displayed greater foot placement standard deviation values (P < 0.05), indicative of adaptation to task constraints. The results of this study provide new methods for sport scientists, coaches to characterize stability in agility drill performance.

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This dissertation provides a synchronic grammatical description of Mauwake, a Papuan (Trans-New Guinea) language of about 2000 speakers on the North Coast of the Madang Province in Papua New Guinea. The theoretical background is that of Basic Linguistic Theory (BLT), used extensively in analysing and writing descriptive grammars. The chapters from morphology to clause level are described from form to function; in the later chapters the function is taken more often as the starting point. Any theory-specific terminology is kept to the minimum and formalisms have been avoided in accordance with BLT principles. Mauwake has a classic 5-vowel system and 14 consonant phonemes. With its simple phonology it is a typical representative of the Madang North Coast languages. For a Papuan language there are relatively few morphophonological alternations. Nouns are either alienably or inalienably possessed. There is no obligatory number marking in nouns or noun phrases. Pronouns have several different forms: five for case and three for other functions. The dative pronouns are treated as [+human] locatives, and they have also grammaticalised as possessives. The verbal morphology is agglutinative and mainly suffixal. Unusual features include two distributive suffixes, and the interaction of the derivational benefactive and the inflectional beneficiary suffixes. The applicative suffix has either transitivising or causative but not benefactive function. The switch-reference system distinguishes between simultaneous and sequential action, as well as same or different subject in relation to the following clause. There are several verbs denoting coming and going, and they may combine with one of three prefixes to indicate bringing and taking. Mauwake is a nominative-accusative type language, and the basic constituent order in a clause is SOV. Subject and object are the only syntactic arguments. There is no indirect object, but a clause can have two or even three objects. A nominalised clause with a finite verb functions as a relative clause or a complement clause; one with a nominalised verb has several different functions. Functional domains described include modality, negation, deixis, quantification, possession and comparison. As there are four negators, Mauwake has more variation in negative expressions than is usual in Papuan languages. Clause chaining is the preferred strategy for joining clauses into sentences, but coordination and subordination of finite clauses are also common. The form of a complement clause depends on whether it is of the fact, action or potential type. Tail-head linkage is used as a cohesive device between sentences. The discourse-level features described are topic and focus.

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A method employing two liquid crystals of opposite diamagnetic anisotropies to determine chemical shift anisotropy without using any reference compound is described. It also provides individual values of the direct and the indirect spin-spin coupling constants between heteronuclei. The parameters for acetonitrile are reported.

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The aim of this study was to compare the use of indirect haemagglutination (IHA) and gel diffusion (GD) tests for serotyping Haemophilus parasuis by the Kielstein-Rapp-Gabrielson scheme. All 15 serovar reference strains, 72 Australian field isolates, nine Chinese field isolates, and seven isolates from seven experimentally infected pigs were evaluated with both tests. With the IHA test, 14 of the 15 reference strains were correctly serotyped – with serovar 10 failing to give a titre with serovar 10 antiserum. In the GD test, 13 reference strains were correctly serotyped – with antigen from serovars 7 and 8 failing to react with any antiserum. The IHA methodology serotyped a total of 45 of 81 field isolates while the GD methodology serotyped a total of 48 isolates. For 29 isolates, the GD and IHA methods gave discordant results. It was concluded that the IHA is a good additional test for the serotyping of H. parasuis by the KRG scheme if the GD methodology fails to provide a result or shows unusual cross-reactions.

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Neopolycystus sp. is the only primary egg parasitoid associated with the pest beetle Paropsis atomaria in subtropical eucalypt plantations, but its impact on its host populations is unknown. The simplified ecosystem represented by the plantation habitat, lack of interspecific competition for host and parasitoid, and the multivoltinism of the host population makes this an ideal system for quantifying the direct and indirect effects of egg parasitism, and hence, effects on host population dynamics. Within-, between- and overall-egg-batch parasitism rates were determined at three field sites over two field seasons, and up to seven host generations. The effect of exposure time (egg batch age), host density proximity to native forest and water sources on egg parasitism rates was also tested. Neopolycystus sp. exerts a significant influence on P. atomaria populations in Eucalyptus cloeziana. plantations in south-eastern Queensland, causing the direct (13%) and indirect (15%) mortality of almost one-third of all eggs in the field. Across seasons and generations, 45% of egg batches were parasitised, with a within-batch parasitism rate of around 30%. Between-batch parasitism increased up to 5-6 days after oviposition in the field, although within-batch parasitism rates generally did not. However, there were few apparent patterns to egg parasitism, with rates often varying significantly between sites and seasons.

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The number of genetic factors associated with common human traits and disease is increasing rapidly, and the general public is utilizing affordable, direct-to-consumer genetic tests. The results of these tests are often in the public domain. A combination of factors has increased the potential for the indirect estimation of an individual's risk for a particular trait. Here we explain the basic principals underlying risk estimation which allowed us to test the ability to make an indirect risk estimation from genetic data by imputing Dr. James Watson's redacted apolipoprotein E gene (APOE) information. The principles underlying risk prediction from genetic data have been well known and applied for many decades, however, the recent increase in genomic knowledge, and advances in mathematical and statistical techniques and computational power, make it relatively easy to make an accurate but indirect estimation of risk. There is a current hazard for indirect risk estimation that is relevant not only to the subject but also to individuals related to the subject; this risk will likely increase as more detailed genomic data and better computational tools become available.

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OBJECTIVE Quantitative assessment of small fiber damage is key to the early diagnosis and assessment of progression or regression of diabetic sensorimotor polyneuropathy (DSPN). Intraepidermal nerve fiber density (IENFD) is the current gold standard, but corneal confocal microscopy (CCM), an in vivo ophthalmic imaging modality, has the potential to be a noninvasive and objective image biomarker for identifying small fiber damage. The purpose of this study was to determine the diagnostic performance of CCM and IENFD by using the current guidelines as the reference standard. RESEARCH DESIGN AND METHODS Eighty-nine subjects (26 control subjects and 63 patients with type 1 diabetes), with and without DSPN, underwent a detailed assessment of neuropathy, including CCM and skin biopsy. RESULTS Manual and automated corneal nerve fiber density (CNFD) (P < 0.0001), branch density (CNBD) (P < 0.0001) and length (CNFL) (P < 0.0001), and IENFD (P < 0.001) were significantly reduced in patients with diabetes with DSPN compared with control subjects. The area under the receiver operating characteristic curve for identifying DSPN was 0.82 for manual CNFD, 0.80 for automated CNFD, and 0.66 for IENFD, which did not differ significantly (P = 0.14). CONCLUSIONS This study shows comparable diagnostic efficiency between CCM and IENFD, providing further support for the clinical utility of CCM as a surrogate end point for DSPN.