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1.
Ecol Appl ; 25(1): 200-14, 2015 Jan.
Article de Anglais | MEDLINE | ID: mdl-26255368

RÉSUMÉ

Resources for conserving biodiversity are invariably insufficient. This situation creates the need for transparent, systematic frameworks to help stakeholders prioritize the allocation of resources across multiple management actions. We developed a novel framework that explicitly prioritizes actions to minimize the impacts of several threats across a species' range. The framework uses a budget constraint and maximizes conservation outcomes from a set of management actions, accounting for the likelihood of the action being successfully applied and accepted by local and Indigenous communities. This approach is novel in that it integrates local knowledge and expert opinion with optimization software, thereby minimizing assumptions about likelihood of success of actions and their effectiveness. To test the framework, we used the eastern Gulf of Carpentaria and Torres Strait population of the flatback turtle, Natator depressus, as a case study. This approach allowed the framework to be applied in a data-poor context, a situation common in conservation planning. The framework identified the best set of actions to maximize the conservation of flatback eggs for scenarios with different budgets and management parameters and allowed comparisons between optimized and preselected scenarios. Optimized scenarios considered all implementable actions to explore how to best allocate resources with a specified budget and focus. Preselected scenarios were used to evaluate current allocations of funds and/or potential budget allocations suggested by different stakeholders. Scenarios that used a combination of aerial and ground strategies to reduce predation of eggs performed better than scenarios that focused only on reducing harvest of eggs. The performances of optimized and preselected scenarios were generally similar among scenarios that targeted similar threats. However, the cost-effectiveness of optimized scenarios was usually higher than that of preselected scenarios, demonstrating the value of conducting a systematic optimization approach. Our method provides a foundation for more effective conservation investments and guidance to prioritize actions within recovery plans while considering the sociopolitical and cultural context of decisions. The framework can be adapted easily to a wide range of species, geographical scales, and life stages.


Sujet(s)
Conservation des ressources naturelles/méthodes , Espèce en voie de disparition , Tortues/physiologie , Animaux , Australie , Prise de décision , Comportement de nidification , Océan Pacifique , Reproduction/physiologie
2.
Neurology ; 67(4): 697-9, 2006 Aug 22.
Article de Anglais | MEDLINE | ID: mdl-16728648

RÉSUMÉ

LRRK2 G2019S is the most common known cause of Parkinson disease (PD) in patients of European origin, but little is known about its distribution in other populations. The authors identified two of 586 Japanese patients with PD heterozygous for the mutation who shared a haplotype distinct from that observed in Europeans. This suggests that G2019S originated from separate founders in Europe and Japan and is more widely dispersed than previously recognized.


Sujet(s)
Haplotypes/génétique , Maladie de Parkinson/épidémiologie , Maladie de Parkinson/génétique , Protein-Serine-Threonine Kinases/génétique , Appréciation des risques/méthodes , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Analyse de mutations d'ADN , Femelle , Marqueurs génétiques/génétique , Prédisposition génétique à une maladie/épidémiologie , Prédisposition génétique à une maladie/génétique , Humains , Japon/épidémiologie , Leucine-rich repeat serine-threonine protein kinase-2 , Mâle , Adulte d'âge moyen , Mutation , Prévalence , Facteurs de risque , Washington/épidémiologie
3.
Neurology ; 65(5): 741-4, 2005 Sep 13.
Article de Anglais | MEDLINE | ID: mdl-16157909

RÉSUMÉ

Referral-based studies indicate that a mutation (G2019S) in exon 41 of the LRRK2 gene might be a common cause of Parkinson disease (PD). The authors sequenced leucine-rich repeat kinase 2 (LRRK2) exons 31, 35, and 41 in 371 consecutively recruited patients with PD and found mutations in six (1.6%) subjects, including two heterozygous for new putative pathogenic variants (R1441H, IVS31 + 3A-->G). These data confirm the important contribution of LRRK2 to PD susceptibility in a clinic-based population.


Sujet(s)
Prédisposition génétique à une maladie/génétique , Mutation/génétique , Maladie de Parkinson/génétique , Protein-Serine-Threonine Kinases/génétique , Sujet âgé , Analyse de mutations d'ADN , Exons/génétique , Santé de la famille , Femelle , Fréquence d'allèle/génétique , Dépistage génétique , Génotype , Hétérozygote , Homozygote , Humains , Leucine-rich repeat serine-threonine protein kinase-2 , Mâle , Adulte d'âge moyen , Maladie de Parkinson/métabolisme , Pedigree
4.
Exp Neurol ; 194(2): 393-409, 2005 Aug.
Article de Anglais | MEDLINE | ID: mdl-16022867

RÉSUMÉ

Two experiments tested how changing a planned movement affects movement initiation and execution in idiopathic Parkinson's disease (PD) patients. In Experiment 1, PD patients, elderly controls, and young adults performed discrete aiming movements to one of two targets on a digitizer. A precue (80% valid cue and 20% invalid cue of all trials) reflecting the subsequent movement direction was presented prior to the imperative stimulus. All groups produced slower reaction times (RTs) to the invalid precue condition. Only the subgroup of patients with slowest movement time showed a significant prolongation of movement for the invalid condition. This suggests that, in the most impaired patients, modifying a planned action also affects movement execution. In Experiment 2, two-segment aiming movements were used to increase the demand on movement planning. PD patients and elderly controls underwent the two precue conditions (80% valid, 20% invalid). Patients exhibited longer RTs than the controls. RT was similarly increased for the invalid condition in both groups. The patients, however, exhibited longer movement times, lower peak velocities, and higher normalized jerk scores of the first segment in the invalid condition compared to the valid condition. Conversely, the controls showed no difference between the valid and invalid cue conditions. Thus, PD patients demonstrated substantially pronounced movement slowness and variability when required to change a planned action. The results from both experiments suggest that modifying a planned action may continue beyond the initiation phase into the execution phase in PD patients.


Sujet(s)
Cognition/physiologie , Signaux , Mouvement/physiologie , Maladie de Parkinson/physiopathologie , Performance psychomotrice/physiologie , Volition/physiologie , Adulte , Sujet âgé , Femelle , Humains , Mâle , Contraction musculaire/physiologie , Muscles squelettiques/physiopathologie , Tests neuropsychologiques , Maladie de Parkinson/psychologie , Stimulation lumineuse , Temps de réaction/physiologie
5.
J Neurol Neurosurg Psychiatry ; 74(3): 299-304, 2003 Mar.
Article de Anglais | MEDLINE | ID: mdl-12588912

RÉSUMÉ

OBJECTIVES: To systematically investigate the ability of Parkinson's disease patients to discretely and dynamically scale the size of continuous movements and to assess the impact of movement size on outcome variability. METHODS: Ten patients with Parkinson's disease (mean age 72 years) were compared with 12 healthy elderly controls (mean age 70 years). The subjects wrote with a stylus on a graphics tablet. In experiment 1 they drew circles, matching the size of five target circles ranging in magnitude from a radius of 0.5 cm up to 2.5 cm. In experiment 2 they drew spirals with a radius of at least 2 cm. In both experiments the drawings were initially performed as accurately as possible then as fast and accurately as possible. RESULTS: In both experiments the patients and controls drew at a similar speed. The within trial variability of the pen trajectory was greater for patients than controls, and increased disproportionately with the size of the movement. When the emphasis was on size rather than variability (circles), the patients' drawing movements were the same size as controls. When the emphasis was on accuracy of pen trajectory (that is, minimum variability) rather than size (spirals), the patients' drawing movements were smaller than controls. CONCLUSIONS: The movements made by Parkinson's disease patients are hypometric partly as an adaptive strategy used to reduce movement variability. This strategy is used primarily when the requirement to make accurate movements outweighs the need to make large movements.


Sujet(s)
Attitude , Maladie de Parkinson , Troubles psychomoteurs/diagnostic , Perception de la taille , Sujet âgé , Sujet âgé de 80 ans ou plus , Femelle , Humains , Mâle , Adulte d'âge moyen , Indice de gravité de la maladie , Facteurs temps
6.
Lymphology ; 24(4): 174-83, 1991 Dec.
Article de Anglais | MEDLINE | ID: mdl-1791728

RÉSUMÉ

Whereas clinical descriptions of grotesque lymphedema and standard light microscopy in human filariasis have elucidated the natural progression of this disease, the link between the nematode and vascular abnormalities including elephantiasis remains poorly understood. Accordingly, we examined the nature and distribution of lymphatic and blood vascular derangements in a variety of tissues and organs from 37 ferrets acutely and chronically infected with Brugia malayi and in 15 patients with Wuchereria bancrofti or Brugia malayi infestation (resected skin, subcutaneous tissue, and lymph nodes) using light and transmission electron microscopy, immunohistochemistry, and in vivo microscopy. In ferrets, eosinophilic abscesses and epithelioid and giant cell granulomas with fragmented worms in various stages of disintegration were found in multiple organs. Blood microvasculopathy consisted of endothelial hyperplasia, focal thickening and stenosis, vessel obliteration with marked perivascular infiltration of lymphocytes, plasma cells, eosinophils, and numerous large macrophages laden with a coarse golden-brown pigment. Endothelial ballooning and swelling, pavementing, denuding, scarring, and sludge formation were seen along with high endothelium in atypical locations. Dilated lymphatics were most prominent near adult worms and showed plump endothelium, thickened walls and valves, thrombus formation, and often perilymphangitis and adjacent tissue fibrosis. In vivo microscopy showed wriggling live adult worms in dilated incompetent sludge-filled groin lymphatics even when microfilaremia and peripheral edema were absent. In human tissues, in addition to "pachyderm" skin changes (keratosis, papillomatosis, acanthosis and collagen deposition), there was blood vessel and lymphatic vasculopathy similar to ferrets (angiocentric inflammation, congestion, vasculitis, thrombosis, thickened vessel walls, dilated lymphatics, lymphangitis, reactive lymph nodal hyperplasia and nodal fibrosis). These changes reflect generalized endothelial damage due to worm products, physical injury to valves and vessel walls from lymphatic-dwelling live worms, and host immune reactivity. Whereas adult worms target the lymphatic apparatus, their offspring and the host immune response primarily affects the blood microvasculature.


Sujet(s)
Vaisseaux sanguins/anatomopathologie , Brugia , Filariose lymphatique/anatomopathologie , Système lymphatique/anatomopathologie , Wuchereria bancrofti , Animaux , Vaisseaux sanguins/métabolisme , Vaisseaux sanguins/parasitologie , Filariose lymphatique/métabolisme , Filariose lymphatique/parasitologie , Furets , Humains , Immunohistochimie , Noeuds lymphatiques/métabolisme , Noeuds lymphatiques/parasitologie , Noeuds lymphatiques/anatomopathologie , Système lymphatique/métabolisme , Système lymphatique/parasitologie , Mâle , Microscopie électronique à balayage , Peau/métabolisme , Peau/parasitologie , Peau/anatomopathologie
7.
Scand Audiol ; 9(1): 33-9, 1980.
Article de Anglais | MEDLINE | ID: mdl-7444318

RÉSUMÉ

Ipsilateral acoustic reflex eliciting stimuli were presented via the probes of six impedance meters to cadaver ears to determine the minimum stimulus levels at which apparent impedance changes occurred. These artefactual indications of impedance change were detected in all but one instrument within the range of intensities available for all frequencies tested. The remaining instrument employs a pulsed stimulus technique which attempts to avoid the artefact problem, and this device only produced artefacts at one frequency and at relatively higher levels than the other instruments. Attempts were made to increase the minimum intensities at which artefacts occurred by introducing various pressure differentials across the tympanic membrane. Generally only small (< 10 dB) increases in the artefact threshold were obtained in this way, although with one instrument there were somewhat larger increases.


Sujet(s)
Tests d'impédance acoustique/méthodes , Réflexe stapédien , Tests d'impédance acoustique/instrumentation , Adulte , Sujet âgé , Cadavre , Femelle , Humains , Mâle , Adulte d'âge moyen , Pression
8.
Scand Audiol ; 8(2): 93-9, 1979.
Article de Anglais | MEDLINE | ID: mdl-515694

RÉSUMÉ

Hearing levels for ipsilateral impedance probes have not yet been established. This study compares two techniques for "transfer of threshold" from the standardised TDH-39 earphone to the unstandardised probe. Ten normal hearing subjects participated, using both a loudness balance technique and a reflex measurement technique. The reflex measurement technique involved comparing the intensity required from each transducer to produce an equal reflex response, whereas the loudness balance technique compared the intensity required from each transducer for equal loudness. The two techniques were found to differ significantly in terms of the Hearing Level values which they produced. Differences between techniques amounted to approximately 3 dB at 1000 Hz, 11 dB at 2000 Hz, and 7 dB at 3000 Hz. As a comparison of the two techniques, the day to day variances were statistically estimated. The reflex measurement technique was shown to be more reliable than the loudness balance technique.


Sujet(s)
Tests d'impédance acoustique/normes , Réflexe stapédien , Tests d'impédance acoustique/instrumentation , Tests d'impédance acoustique/méthodes , Adulte , Analyse de variance , Femelle , Humains , Mâle
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