383 research outputs found
Interlimb transfer of unimanual grasping movement in upper limb amputees - A pilot study.
Background. Inter-hemispheric communication is necessary during uni- manual grip of an object (1). The right and left hands share a level of representation in the motor program that is common to both (2). It could be essential to take into consideration bi- hemispheric activity to adapt prosthesis of individuals with upper limb amputation.\ud
Objective. To determine the relevance of the inter-hemispheric dependence in the programing and execution of uni-manual grip in individuals with upper limb amputation.\ud
Methods. Five adults with amputation of the upper limb above and below the elbow participated in this study. Each participant was seated and asked to grab and lift an instrumented cylinder with the sound hand 15 times (Figure 1). The cylinder enabled to record in real time the apposition axis (AO) passing by the thrum, the centre of the cylinder and the first finger as well as the forces applied during the griping period of 2000 ms. The participants were assessed during the temporary (PP) and definitive (PD) phases of prosthesis fitting the after the amputation. Student t-tests were used to determine the effect of different prosthetic phases on the force and orientation of the griping hand.\ud
Results\ud
1. A significant reduction (p<0.01) of the forces applied by the sound hand between the two prosthetic phase for 4/5 of the participants (Figure 2)\ud
2. Some changes in the gripping orientation when the amputated hand was dominant for 2/3 of the participants (Figure 3) 3. No changes in the gripping orientation when the amputated hand was not dominant\ud
Conclusion. Grip programming and execution with sound hand:\ud
1. Change between two prosthetic fitting phases\ud
2. Depend on the inter-hemispheric transfer related to the force regardless on the amputated hand.\ud
3. Depend on the inter-hemispheric transfer related to the gripping orientation only when the amputated side is dominant.\ud
Adjustments in griping force and orientation of the prosthesis depending on the grip correction of the sound hand might be respectively more necessary regardless of the amputated hand and when the amputated hand is dominant.\ud
Because of the variability between participants concerning the side of amputation and manual dominance, other studies will be required to generalise these results
A dual isotopic approach using radioactive phosphorus and the isotopic composition of oxygen associated to phosphorus to understand plant reaction to a change in P nutrition
Abstract Background Changing the phosphorus (P) nutrition leads to changes in plant metabolism. The aim of this study was to investigate how these changes are reflected in the distribution of 33P and the isotopic composition of oxygen associated to P (ÎŽ18OP) in different plant parts of soybean (Glycine max cv. Toliman). Two P pools were extracted sequentially with 0.3 M trichloroacetic acid (TCA P) and 10 M nitric acid (HNO3; residual P). Results The ÎŽ18OP of TCA P in the old leaves of the â P plants (23.8â°) significantly decreased compared to the + P plants (27.4â°). The 33P data point to an enhanced mobilisation of P from residual P in the old leaves of the â P plants compared to the + P plants. Conclusions Omitting P for 10 days lead to a translocation of P from source to sink organs in soybeans. This was accompanied by a significant lowering of the ÎŽ18OP of TCA P in the source organs due to the enzymatic hydrolysis of organic P. Combining 33P and ÎŽ18OP can provide useful insights in plant responses to P omission at an early stage
Fertilization of Dioscorea rotundata with poultry manure: effects on nutrient dynamics and nutrient use efficiencies. Awarded poster presentation
Similar effects of poultry manure (PM) and mineral fertilizer suggest that PM is a cheap and effective alternative to fertilizers for yam production
Fertilization of Dioscorea rotundata with poultry manure: effects on nutrient dynamics and nutrient use efficiencies
Similar effects of poultry manure (PM) and mineral fertilizer suggest that PM is a cheap and effective alternative to fertilizers for yam production
Distributed coding of multiresolution omnidirectional images
This paper addresses the problem of compact representation of a 3D scene, captured by distributed omnidirectional cameras. As the images from the sensors are likely to be correlated in most practical scenarios, we build a distributed algorithm based on coding with side information. A reference image is processed with a wavelet transform and progressively encoded. The Wyner-Ziv images undergo a multiresolution representation, and the generated bitplanes are channel encoded with LDPC codes. The central decoder eventually reconstructs the Wyner-Ziv images given by the syndrome bits from the channel codes using the reference omnidirectional image. It also iteratively implements motion estimation on the 2-sphere in order to improve the side information. Experimental results demonstrate that distributed coding improves the rate-distortion performance for coding a set of omnidirectional images when compared to independent coding solutions. The proposed method can further be extended to the decoding of multiple Wyner-Ziv images using one single reference omnidirectional image. Hence, it achieves a reduced overall coding rate compared to disparity-based schemes. In addition, it does not require explicit knowledge of the camera parameters nor precise calibration, which is certainly interesting in camera networks
Balanced Distributed Coding of Omnidirectional Images
This paper presents a distributed coding scheme for the representation of 3D scenes captured by a network of omnidirectional cameras. We consider a scenario where images captured at different viewpoints are encoded independently, with a balanced rate distribution among the different cameras. The distributed coding is built on multiresolution representation and partitioning of the visual information in each camera. The encoder then transmits one partition after entropy coding, as well as the syndrome bits resulting from the channel encoding of the other partition. The joint decoder exploits the intra-view correlation by predicting the missing source information with help of the syndrome bits. At the same time, it exploits the inter-view correlation by using motion estimation between images from different cameras. Experiments demonstrate that the distributed coding solution performs better than a scheme where images are handled independently, while the coding rate advantageously stays balanced between encoders
Bronchial responses to substance P after antigen challenge in the guinea-pig: in vivo and in vitro studies
The effect of antigen challenge on the airway responses to substance P and on the epithelial neutral endopeptidase (NEP) activity was investigated in aerosol sensitized guinea-pigs. In vivo, bronchial responses to aerosolized substance P were similar to the responses observed in antigen-challenged guinea-pigs and in the control groups. In contrast, when the guinea-pigs were pretreated with the NEP inhibitor, phosphoramidon, a significant increase in the airway responses to substance P was observed after antigen challenge in vivo. However, in vitro, the contractile responses of the tracheal smooth muscle to substance P were similar between groups of guinea-pigs, in respect to the presence or absence of the epithelium and/or phosphoramidon. Histological studies showed an accumulation of eosinophils in the tracheal submucosa after antigen challenge and intact epithelial cells. These results show that in vivo bronchial hyperresponsiveness to substance P after antigen challenge in the guinea-pig is not associated with increased responses of the smooth muscle to exogenous SP in vitro. In addition, the results with phosphoramidon suggest that loss of NEP activity cannot account for the in vivo bronchial hyperresponsiveness to substance P presently observed
Conjunctival MALT lymphoma: utility of FDG PET/CT for diagnosis, staging, and evaluation of treatment response.
A 67-year-old woman was referred for staging of a mucosa-associated lymphoid tumor lymphoma involving the left conjunctiva. CT scan had shown paravertebral and pelvic masses, and a breast nodule. FDG PET/CT demonstrated moderately increased uptake in the left ocular conjunctiva and confirmed the paravertebral and pelvic masses and the breast nodule. Moreover, abnormal FDG uptake was shown in 2 breast nodules, the flank, the gluteus maximus, and the gastric cardia. The patient received 6 cycles of rituximab-bendamustine chemotherapy with a complete clinical and metabolic response at the 6-month follow-up PET/CT and remained relapse-free without visual acuity problem after a 36-month follow-up
Phosphorus species in sequentially extracted soil organic matter fractions
The majority of organic P (Porg) in soil is considered to be part of soil organic matter (SOM) associations, but its chemical nature is largely âunresolvedâ. In this study, we investigated the Porg composition in different SOM fractions of a Gleysol soil using the Humeomics sequential chemical fractionation (SCF) procedure combined with nuclear magnetic resonance (NMR) spectroscopy.
In summary, SCF procedure with subsequent NaOH-EDTA extraction of the soil residue extracted a total of 1769 mg P/kgsoil compared to 1682 mg P/kgsoil of a single-step NaOH-EDTA extraction. Approximately 38 % of the extracted Porg was present in the form of the unresolved Porg pool, which was represented by one or two underlying broad signals in the phosphomonoester region of solution 31P NMR spectra. The SCF revealed that phosphomonoesters were recovered in each fraction: 47 % of the unresolved phosphomonoesters were associated with the SOM fraction released by breaking ester bonds (40 %) and ether bonds (7 %), whereas about 30 % of this unresolved Porg pool appeared in the SOM fraction closely associated with the soil mineral phase. Furthermore, the extractability of inositol phosphates (IP) was increased from 312 mg P/kgsoil to 534 mg P/kgsoil (factor 1.7) using the SCF procedure compared to a single-step NaOH-EDTA extraction. Previous studies have reported the presence of IP in molecular size fractions greater than 10 kDa. Our findings on the removal of IP with the fractionation of the SOM could explain the presence of IP in these large associations.
We demonstrate that major pools of Porg are closely associated with SOM structures, comprising a diverse array of chemical species and bonding types. These results forward our understanding of Porg stabilisation, P transformation, and P cycling in terrestrial ecosystems towards an association point of view
The interaction between warming and enrichment accelerates foodâweb simplification in freshwater systems
Nutrient enrichment and climate warming threaten freshwater systems. Metabolic theory and the paradox of enrichment predict that both stressors independently can lead to simpler food-webs having fewer nodes, shorter food-chains and lower connectance, but cancel each other's effects when simultaneously present. Yet, these theoretical predictions remain untested in complex natural systems. We inferred the food-web structure of 256 lakes and 373 streams from standardized fish community samplings in France. Contrary to theoretical predictions, we found that warming shortens fish food-chain length and that this effect was magnified in enriched streams and lakes. Additionally, lakes experiencing enrichment exhibit lower connectance in their fish food-webs. Our study suggests that warming and enrichment interact to magnify food-web simplification in nature, raising further concerns about the fate of freshwater systems as climate change effects will dramatically increase in the coming decades
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