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1.
Sci Total Environ ; 754: 142416, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254933

RESUMO

Large mammals that occur in low densities, particularly in the high-altitude areas, are globally threatened due to fragile climatic and ecological envelopes. Among bear species, the Himalayan brown bear (Ursus arctos isabellinus) has a distribution that is restricted to Himalayan highlands with relatively small and fragmented populations. To date, very little scientific information on the Himalayan brown bear, which is vital for the conservation of the species and the management of its habitats, especially in protected areas of the landscape, is available. The present study aims to understand the effectiveness of existing Himalayan Protected Areas in terms of representativeness for the conservation of Himalayan brown bear (HBB), an umbrella species in high-altitude habitats of the Himalayan region. We used the ensemble approach of the species distribution model and then assessed biological connectivity to predict the current and future distribution and movement of HBB in climate change scenarios for the year 2050. Approximately 33 protected areas (PAs) currently possess suitable habitats. Our model suggests a massive decline of approximately 73.38% and 72.87% under 4.5 and 8.5 representative concentration pathway (RCP) respectively in the year 2050 compared with the current distribution. The predicted change in suitability will result in loss of habitats from thirteen PAs; eight will become completely uninhabitable by the year 2050, followed by loss of connectivity in the majority of PAs. Habitat configuration analysis suggested a 40% decline in the number of suitable patches, a reduction in large habitat patches (up to 50%) and aggregation of suitable areas (9%) by 2050, indicating fragmentation. The predicted change in geographic isotherm will result in loss of habitats from thirteen PAs, eight of them will become completely inhabitable. Hence, these PAs may lose their effectiveness and representativeness in achieving the very objective of their existence or conservation goals. Therefore, we recommend adaptive spatial planning for protecting suitable habitats distributed outside the PA for climate change adaptation.


Assuntos
Ursidae , Aclimatação , Animais , Mudança Climática , Conservação dos Recursos Naturais , Ecossistema , Objetivos , Movimento
2.
Pest Manag Sci ; 77(1): 85-95, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32738020

RESUMO

BACKGROUND: Lethal removal of invasive species, such as wild pigs (Sus scrofa), is often the most efficient approach for reducing their negative impacts. Wild pigs are one of the most widespread and destructive invasive mammals in the USA. Lethal management techniques are a key approach for wild pigs and can alter wild pig spatial behavior, but it is unclear how wild pigs respond to the most common removal technique, trapping. We investigated the spatial behavior of wild pigs following intensive removal of conspecifics via trapping at three sites within the Savannah River Site, SC, USA. We evaluated changes in wild pig densities, estimated temporal shifts in home-range properties, and evaluated fine-scale movement responses of wild pigs to removal. RESULTS: We observed a significant reduction in the density of wild pigs in one site following removal via trapping while a qualitative reduction was observed in another site. We found little evidence of shifts in pig home-ranging behavior following removal. However, we did observe a nuanced response in movement behavior of wild pigs to the removal at the scale of the GPS locations (4 h), including increased movement speed and reduced selection for vegetation rich areas. CONCLUSION: Our work provides a better understanding of the impact of removal via trapping on wild pig movement and its implications for management. The lack of shift in home-range characteristics observed illustrates how targeted trapping could be used to provide temporary relief for species sensitive to wild pig consumption such as ground nesting birds or agricultural crops.


Assuntos
Espécies Introduzidas , Sus scrofa , Animais , Produtos Agrícolas , Movimento , Suínos
3.
Dentomaxillofac Radiol ; 50(1): 20200255, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32706986

RESUMO

OBJECTIVES: To assess quantitatively the combined effect of exomass-related- and motion artefacts on voxel value parameters in cone beam CT (CBCT). METHODS: A cylindrical phantom was manufactured, containing 21 tubes filled with a radiopaque solution, allowing the inclusion of three titanium implants in the periphery to induce exomass-related artefacts. The phantom was mounted on a robot simulating 0.75-, 1.5-, and 3 mm movements (nodding/lateral rotation/tremor). CBCT images with/without exomass and with/without movements were acquired in duplicate in three units: Cranex 3Dx, Orthophos SL-3D, and X1 (with motion-artefact correction). A cylindrical volume of interest was defined in each tube and voxel value mean and standard deviation were assessed. For each CBCT volume, the 21 mean voxel values were averaged providing the overall mean voxel value (MVV), and the standard deviation (among the 21 values) was calculated providing overall voxel value inhomogeneity (VVI). The standard deviation from each of the 21 volumes-of-interest were averaged, providing overall image noise (IN). The effect of the diverse tested situations was inferred from a repeated-measures analysis of variance, followed by Sidak's test (α = 0.05). RESULTS: Overall, images acquired with exomass showed significantly (p ≤ 0.05) lower MVV, and higher VVI and IN. Motion artefacts aggravated exomass-related alterations. MVV and VVI were mostly affected by 3 mm nodding movements. Motion-artefact correction eliminated the deleterious effect of movement. CONCLUSIONS: CBCT voxel-value parameters are altered by exomass-related artefacts, and this finding is aggravated in the presence of motion artefacts. Motion-artefact correction effectively eliminated the deleterious impact of movement.


Assuntos
Artefatos , Tomografia Computadorizada de Feixe Cônico , Movimento , Imagens de Fantasmas , Rotação
4.
Med Probl Perform Art ; 35(4): 202-207, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33257922

RESUMO

AIMS: Although the significance of upper-body posture in relation to piano performance has often been highlighted, the role of experience remains unclear. The aim of this study was to examine selected upper body posture parameters in adolescent piano students of different performance level (beginners vs advanced). METHODS: Thirteen (13) adolescent piano students (14.7±0.5 yrs; 7 beginners and 6 advanced) volunteered. They all performed two specific major scales (G-major and E-major) in five octaves in two predetermined different tempi (slow and fast). An upper body biomechanical model consisting of 27 reflective markers was applied on specific bony landmarks. A 10-T camera Vicon system running Nexus 2 was employed to capture upper body motion--a) sway of the trunk in relation to the instrument, b) finger/hand sway over the keyboard, c) overall hand movement, and d) spinal angles--at selected moments of four different performances. RESULTS: Beginners demonstrated more trunk sway than their advanced counterparts (p<0.05), more finger/hand sway (p<0.05), more overall hand movement (p<0.05), and more flexed spinal angles at the start of their performance (p<0.05). Most of these differences appeared in the G-fast performances, whereas the G-slow equivalents revealed no differences. CONCLUSION: Less-experienced piano players are characterized by more movement in their trunk posture and more upper limb activity than their more advanced colleagues. Future research should examine whether interventional programs designed to alter upper-body posture would have beneficial effects in piano performance.


Assuntos
Mãos , Postura , Adolescente , Fenômenos Biomecânicos , Estudos Transversais , Humanos , Movimento , Tronco
5.
Artigo em Russo | MEDLINE | ID: mdl-33306300

RESUMO

BACKGROUND: Complicated spinal cord injury occurs in 1-5 cases per 100.000. In children, cervical trauma makes up 72% of all spinal trauma. Spinal cord injury complicates vertebral trauma in 25-50% of cases that usually results severe disability. Rehabilitation of these patients is usually ineffective or results a little improvement. Restoration of even minimal movements is essential in these patients. There are reports devoted to surgical rehabilitation of important hand functions after cervical spinal cord injury. OBJECTIVE: To demonstrate the restoration of key hand functions in patients with CV-CVII complicated spinal cord injury using selective neurotization of the median nerve. MATERIAL AND METHODS: Three patients aged 17-19 years with complicated CV-CVII spinal cord injury and ASIA class A have been selected for surgery for 2 years. Mean period after rehabilitation was 11.3 months. Prior to surgery, all patients recovered flexion/extension in the elbow joints, forearm rotation, flexion and extension of hands. However, there were no active movements in distal phalanges of the fingers, and initial signs of flexor contracture were observed. RESULTS: Surgical strategy included selective neurotization of the median nerve with a motor branch of musculocutaneous nerve. In one case, we used additional neurotization of posterior interosseous nerve. Two patients recovered cylindrical grip up to M4 and pinch grip up to M3 within 15 months. In the third patient, postoperative data were not assessed due to short-term follow-up. CONCLUSION: Selective neurotization of anterior interosseous nerve may be considered as a stage or independent surgery for restoration of key hand functions. This approach improves the quality of life in patients with complicated spinal cord injury.


Assuntos
Transferência de Nervo , Traumatismos da Medula Espinal , Adolescente , Adulto , Criança , Humanos , Nervo Mediano , Movimento , Qualidade de Vida , Adulto Jovem
6.
Artigo em Inglês | MEDLINE | ID: mdl-33266407

RESUMO

Functional movement is an important part of developing athletes' but also untrained individuals' performance. Its monitoring also proved useful in identifying functional limitations and asymmetries, and also in determining the intervention effects. The quasi-experimental pre-test post-test study investigated the effects of core stability training program on the Functional Movement Screen (FMS) score in untrained students after six weeks. The intervention (INT) and control (CG) groups included 73 and 65 male students, respectively. Functional movement patterns were evaluated using the FMS including seven components scores representing seven basic functional patterns. Both groups significantly improved almost all FMS components scores, but the INT increased the mean performance of the hurdle step (partial ŋ2 × 100 = 4%, p = 0.02), in-line lunge (partial ŋ2 × 100 = 3%, p = 0.05), rotatory stability (partial ŋ2 × 100 = 4%, p = 0.02) and total FMS (partial ŋ2 × 100 = 3%, p = 0.04) significantly more than the CG. This justifies that core strengthening can improve FMS in untrained individuals even with the short duration programs.


Assuntos
Teste de Esforço , Movimento , Força Muscular , Atletas , Humanos , Masculino , Estudantes , Fatores de Tempo
7.
PLoS One ; 15(12): e0241117, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33326434

RESUMO

Deafferentation and weight offloading can increase brain and spinal motor neuron excitability, respectively. End-effector gait robots (EEGRs) can blend these effects with stereotyped movement-induced neuroplasticity. The authors aimed to evaluate the usefulness of EEGRs as a postoperative neuro-muscular rehabilitation tool. This prospective randomized controlled trial included patients who had undergone unilateral total knee arthroplasty (TKA). Patients were randomly allocated into two groups: one using a 200-step rehabilitation program in an EEGR or the other using a walker on a floor (WF) three times a day for five weekdays. The two groups were compared by electrophysiological and biomechanical methods. Since there were no more enrollments due to funding issues, interim analysis was performed. Twelve patients were assigned to the EEGR group and eight patients were assigned to the WF group. Although the muscle volume of the quadriceps and hamstring did not differ between the two groups, the normalized peak torque of the operated knee flexors (11.28 ± 16.04 Nm/kg) was improved in the EEGR group compared to that of the operated knee flexors in the WF group (4.25 ± 14.26 Nm/kg) (p = 0.04). The normalized compound motor action potentials of the vastus medialis (VM) and biceps femoris (BF) were improved in the EEGR group (p < 0.05). However, the normalized real-time peak amplitude and total, mean area under the curve of VM were decreased during rehabilitation in the EEGR group (p < 0.05). No significant differences were found between operated and non-operated knees in the EEGR group. Five-day EEGR-assisted rehabilitation induced strengthening in the knee flexors and the muscular reactivation of the BF and VM after TKA, while reducing the real-time use of the VM. This observation may suggest the feasibility of this technique: EEGR modulated the neuronal system of the patients rather than training their muscles. However, because the study was underpowered, all of the findings should be interpreted with the utmost caution.


Assuntos
Artroplastia do Joelho/reabilitação , Osteoartrite do Joelho/reabilitação , Osteoartrite do Joelho/cirurgia , Robótica/instrumentação , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Terapia por Exercício , Feminino , Marcha , Humanos , Articulação do Joelho/fisiopatologia , Articulação do Joelho/cirurgia , Movimento , Osteoartrite do Joelho/fisiopatologia , Estudos Prospectivos , Recuperação de Função Fisiológica , Robótica/métodos , Método Simples-Cego , Andadores , Suporte de Carga/fisiologia
8.
PLoS One ; 15(12): e0239919, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33264326

RESUMO

Storm events are a significant source of disturbance in the Middle Atlantic Bight, in the Northwest Atlantic, that cause rapid destratification of the water column during the late summer and early fall. Storm-driven mixing can be considered as a seasonal disturbance regime to demersal communities, characterized by the recurrence of large changes in bottom water temperatures. Black sea bass are a model ubiquitous demersal species in the Middle Atlantic Bight, as their predominantly sedentary behavior makes them ideal for tagging studies while also regularly exposing them to summer storm disturbances and the physiological stresses associated with thermal destratification. To better understand the responsiveness of black sea bass to storm impacts, we coupled biotelemetry with a high-resolution Finite Volume Community Ocean Model (FVCOM). During the summers of 2016-2018, 8-15 black sea bass were released each year with acoustic transponders at three reef sites, which were surrounded by data-logging receivers. Data were analyzed for activity levels and reef departures of black sea bass, and fluctuations in temperature, current velocity, and turbulent kinetic energy. Movement rates were depressed with each consecutive passing storm, and late-season storms were associated with permanent evacuations by a subset of tagged fish. Serial increases in bottom temperature associated with repeated storm events were identified as the primary depressor of local movement. Storm-driven increases in turbulent kinetic energy and current velocity had comparatively smaller, albeit significant, effects. Black sea bass represents both an important fishery resource and an indicator species for the impact of offshore wind development in the United States. Their availability to fisheries surveys and sensitivity to wind turbine impacts will be biased during periods of high storm activity, which is likely to increase with regional climate change.


Assuntos
Bass/fisiologia , Comportamento Animal/fisiologia , Mudança Climática , Movimento/fisiologia , Tempo (Meteorologia) , Animais , Temperatura
9.
Sci Data ; 7(1): 432, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33319816

RESUMO

MoCA is a bi-modal dataset in which we collect Motion Capture data and video sequences acquired from multiple views, including an ego-like viewpoint, of upper body actions in a cooking scenario. It has been collected with the specific purpose of investigating view-invariant action properties in both biological and artificial systems. Besides that, it represents an ideal test bed for research in a number of fields - including cognitive science and artificial vision - and application domains - as motor control and robotics. Compared to other benchmarks available, MoCA provides a unique compromise for research communities leveraging very different approaches to data gathering: from one extreme of action recognition in the wild - the standard practice nowadays in the fields of Computer Vision and Machine Learning - to motion analysis in very controlled scenarios - as for motor control in biomedical applications. In this work we introduce the dataset and its peculiarities, and discuss a baseline analysis as well as examples of applications for which the dataset is well suited.


Assuntos
Culinária/métodos , Movimento , Fenômenos Biomecânicos , Humanos , Gravação em Vídeo
10.
PLoS One ; 15(11): e0241468, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33166301

RESUMO

In March of this year, COVID-19 was declared a pandemic, and it continues to threaten public health. This global health crisis imposes limitations on daily movements, which have deteriorated every sector in our society. Understanding public reactions to the virus and the non-pharmaceutical interventions should be of great help to fight COVID-19 in a strategic way. We aim to provide tangible evidence of the human mobility trends by comparing the day-by-day variations across the U.S. from January 2020 to early April 2020. Large-scale public mobility at an aggregated level is observed by leveraging mobile device location data and the measures related to social distancing. Our study captures spatial and temporal heterogeneity as well as the sociodemographic variations and teleworking trends regarding the pandemic propagation and the non-pharmaceutical mobility interventions. All metrics adapted capture decreased public movements after the national emergency declaration. The population staying home has increased in all states before the stay-at-home mandates implemented and becomes more stable after the order with a smaller range of fluctuation. The public had been taking active responses, voluntarily staying home more, to the in-state confirmed cases while the stay-at-home orders stabilize the variations. As the estimated teleworking rates also continue to incline throughout the study period, the teleworking trend can be another driving factor for the growing stay-at-home population. We confirm that there exists overall mobility heterogeneity between the income or population density groups. The study suggests that public mobility trends are in line with the government message urging to stay home. We anticipate our data-driven analysis offers integrated perspectives and serves as evidence to raise public awareness and, consequently, reinforce the importance of social distancing while assisting policymakers.


Assuntos
Infecções por Coronavirus/patologia , Movimento , Pneumonia Viral/patologia , Betacoronavirus/isolamento & purificação , Uso do Telefone Celular/estatística & dados numéricos , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Processamento Eletrônico de Dados , Humanos , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Análise Espaço-Temporal , Estados Unidos/epidemiologia
11.
PLoS One ; 15(11): e0241957, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33170889

RESUMO

The current COVID-19 pandemic raises concerns worldwide, leading to serious health, economic, and social challenges. The rapid spread of the virus at a global scale highlights the need for a more harmonized, less privacy-concerning, easily accessible approach to monitoring the human mobility that has proven to be associated with viral transmission. In this study, we analyzed over 580 million tweets worldwide to see how global collaborative efforts in reducing human mobility are reflected from the user-generated information at the global, country, and U.S. state scale. Considering the multifaceted nature of mobility, we propose two types of distance: the single-day distance and the cross-day distance. To quantify the responsiveness in certain geographic regions, we further propose a mobility-based responsive index (MRI) that captures the overall degree of mobility changes within a time window. The results suggest that mobility patterns obtained from Twitter data are amenable to quantitatively reflect the mobility dynamics. Globally, the proposed two distances had greatly deviated from their baselines after March 11, 2020, when WHO declared COVID-19 as a pandemic. The considerably less periodicity after the declaration suggests that the protection measures have obviously affected people's travel routines. The country scale comparisons reveal the discrepancies in responsiveness, evidenced by the contrasting mobility patterns in different epidemic phases. We find that the triggers of mobility changes correspond well with the national announcements of mitigation measures, proving that Twitter-based mobility implies the effectiveness of those measures. In the U.S., the influence of the COVID-19 pandemic on mobility is distinct. However, the impacts vary substantially among states.


Assuntos
Infecções por Coronavirus/patologia , Movimento , Pneumonia Viral/patologia , Mídias Sociais/estatística & dados numéricos , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Humanos , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia
12.
Nature ; 587(7833): 219-224, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33177670

RESUMO

Soft machines are a promising design paradigm for human-centric devices1,2 and systems required to interact gently with their environment3,4. To enable soft machines to respond intelligently to their surroundings, compliant sensory feedback mechanisms are needed. Specifically, soft alternatives to strain gauges-with high resolution at low strain (less than 5 per cent)-could unlock promising new capabilities in soft systems. However, currently available sensing mechanisms typically possess either high strain sensitivity or high mechanical resilience, but not both. The scarcity of resilient and compliant ultra-sensitive sensing mechanisms has confined their operation to laboratory settings, inhibiting their widespread deployment. Here we present a versatile and compliant transduction mechanism for high-sensitivity strain detection with high mechanical resilience, based on strain-mediated contact in anisotropically resistive structures (SCARS). The mechanism relies upon changes in Ohmic contact between stiff, micro-structured, anisotropically conductive meanders encapsulated by stretchable films. The mechanism achieves high sensitivity, with gauge factors greater than 85,000, while being adaptable for use with high-strength conductors, thus producing sensors resilient to adverse loading conditions. The sensing mechanism also exhibits high linearity, as well as insensitivity to bending and twisting deformations-features that are important for soft device applications. To demonstrate the potential impact of our technology, we construct a sensor-integrated, lightweight, textile-based arm sleeve that can recognize gestures without encumbering the hand. We demonstrate predictive tracking and classification of discrete gestures and continuous hand motions via detection of small muscle movements in the arm. The sleeve demonstration shows the potential of the SCARS technology for the development of unobtrusive, wearable biomechanical feedback systems and human-computer interfaces.


Assuntos
Retroalimentação Sensorial , Maleabilidade , Robótica/instrumentação , Robótica/métodos , Interface Usuário-Computador , Dispositivos Eletrônicos Vestíveis , Mãos/fisiologia , Humanos , Movimento (Física) , Movimento , Têxteis
13.
PLoS One ; 15(11): e0232562, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33166291

RESUMO

Children with Developmental Coordination Disorder (DCD) are diagnosed based on motor difficulties. However, they also exhibit difficulties in several other cognitive domains, including visuospatial processing, executive functioning and attention. One account of the difficulties seen in DCD proposes an impairment in internal forward modelling, i.e., the ability to (i) detect regularities of a repetitive perceptual or motor pattern, (ii) predict future outcomes of motor actions, and (iii) adapt behaviour accordingly. Using electroencephalographic recordings, the present study aimed to delineate these different aspects of internal forward modelling across several domains. To this end, 24 children with DCD and 23 typically-developing children (aged 7-10 years) completed a serial prediction task in the visual, temporal, spatial and motor domains. This task required them to learn short sequences and to indicate whether a sequence was disrupted towards its end. Analyses revealed that, across all domains, children with DCD showed poorer discrimination between intact and disrupted sequences, accompanied by a delayed late parietal positivity elicited by disrupted sequences. These results indicate an impairment in explicit sequence discrimination in DCD across motor and cognitive domains. However, there is no evidence for an impairment in implicit performance on the visuomotor task in DCD. These results suggest an impairment of the updating of an internal forward model in DCD resulting in a blurred representation of that model and, consequently, in a reduced ability to detect regularities in the environment (e.g., sequences). Such a detailed understanding of internal forward modelling in DCD could help to explain the wide range of co-occurring difficulties experienced by those with a diagnosis of DCD.


Assuntos
Atenção/fisiologia , Função Executiva/fisiologia , Transtornos das Habilidades Motoras/fisiopatologia , Movimento , Desempenho Psicomotor , Criança , Feminino , Humanos , Aprendizagem , Masculino
14.
PLoS One ; 15(11): e0236768, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33206652

RESUMO

Despite numerous reports of abnormalities in limb motor controls in spatial orientation in individuals with autism spectrum disorder (ASD), the underlying mechanisms have not been elucidated. We studied the influence of allocentric coordinates on ongoing reaching movements, which has been reported to strongly affect the reaching movements of typically developing (TD) individuals. ASD and TD participants observed a target presented randomly on one of the four corners of a frame on a screen. After it disappeared, another frame was presented slightly shifted leftward/rightward. The participants touched the memorized position of the target relatively congruent with a reference frame (allocentric condition) or ignoring it (egocentric condition). Results suggested that TD individuals were apt to touch the positions in allocentric manner rather than egocentric manner, while ASDs did not show this prioritization. Our findings demonstrate that decreased utilization of visual landmarks in ongoing movement may underlie motor disabilities in autism.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Movimento , Orientação/fisiologia , Desempenho Psicomotor , Tempo de Reação/fisiologia , Percepção Espacial/fisiologia , Percepção do Tato/fisiologia , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa , Adulto Jovem
15.
PLoS Biol ; 18(11): e3000882, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33141817

RESUMO

During active tactile exploration, the dynamic patterns of touch are transduced to electrical signals and transformed by the brain into a mental representation of the object under investigation. This transformation from sensation to perception is thought to be a major function of the mammalian cortex. In primary somatosensory cortex (S1) of mice, layer 5 (L5) pyramidal neurons are major outputs to downstream areas that influence perception, decision-making, and motor control. We investigated self-motion and touch representations in L5 of S1 with juxtacellular loose-seal patch recordings of optogenetically identified excitatory neurons. We found that during rhythmic whisker movement, 54 of 115 active neurons (47%) represented self-motion. This population was significantly more modulated by whisker angle than by phase. Upon active touch, a distinct pattern of activity was evoked across L5, which represented the whisker angle at the time of touch. Object location was decodable with submillimeter precision from the touch-evoked spike counts of a randomly sampled handful of these neurons. These representations of whisker angle during self-motion and touch were independent, both in the selection of which neurons were active and in the angle-tuning preference of coactive neurons. Thus, the output of S1 transiently shifts from a representation of self-motion to an independent representation of explored object location during active touch.


Assuntos
Córtex Somatossensorial/fisiologia , Percepção do Tato/fisiologia , Tato/fisiologia , Potenciais de Ação/fisiologia , Animais , Encéfalo/fisiologia , Córtex Cerebral/fisiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Movimento/fisiologia , Neurônios/fisiologia , Vibrissas/fisiologia
16.
Proc Biol Sci ; 287(1938): 20201341, 2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33143585

RESUMO

Corallivorous crown-of-thorns starfishes (Acanthaster spp.) can decimate coral assemblages on Indo-Pacific coral reefs during population outbreaks. While initial drivers of population irruptions leading to outbreaks remain largely unknown, subsequent dispersal of outbreaks appears coincident with depletion of coral prey. Here, we used in situ time-lapse photography to characterize movement of the Pacific crown-of-thorns starfish (Acanthaster cf. solaris) in the northern and southern Great Barrier Reef in 2015, during the fourth recorded population outbreak of the starfish, but prior to widespread coral bleaching. Daily tracking of 58 individuals over a total of 1117 h revealed all starfish to move a minimum of 0.52 m, with around half of all tracked starfish showing negligible daily displacement (less than 1 m day-1), ranging up to a maximum of 19 m day-1. Movement was primarily nocturnal and daily displacement varied spatially with variation in local availability of Acropora spp., which is the preferred coral prey. Two distinct behavioural modes emerged: (i) homing movement, whereby tracked paths (as tested against a random-walk-model) involved short displacement distances following distinct 'outward' movement to Acropora prey (typically displaying 'feeding scars') and 'homebound' movement to nearby shelter; versus (ii) roaming movement, whereby individuals showed directional movement beyond initial tracking positions without return. Logistic modelling revealed more than half of all tracked starfish demonstrated homing when local abundance (percentage cover) of preferred Acropora coral prey was greater than 33%. Our results reveal facultative homing by Acanthaster with the prey-dependent behavioural switch to roaming forays providing a mechanism explaining localized aggregations and diffusion of these population irruptions as prey is locally depleted.


Assuntos
Comportamento de Retorno ao Território Vital , Estrelas-do-Mar/fisiologia , Animais , Antozoários , Recifes de Corais , Movimento
17.
PLoS One ; 15(11): e0242416, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33216756

RESUMO

INTRODUCTION: Illusion of movement induced by tendon vibration is an effective approach for motor and sensory rehabilitation in case of neurological impairments. The aim of our study was to investigate which modality of visual feedback in Virtual Reality (VR) associated with tendon vibration of the wrist could induce the best illusion of movement. METHODS: We included 30 healthy participants in the experiment. Tendon vibration inducing illusion of movement (wrist extension, 100Hz) was applied on their wrist during 3 VR visual conditions (10 times each): a moving virtual hand corresponding to the movement that the participants could feel during the tendon vibration (Moving condition), a static virtual hand (Static condition), or no virtual hand at all (Hidden condition). After each trial, the participants had to quantify the intensity of the illusory movement on a Likert scale, the subjective degree of extension of their wrist and afterwards they answered a questionnaire. RESULTS: There was a significant difference between the 3 visual feedback conditions concerning the Likert scale ranking and the degree of wrist's extension (p<0.001). The Moving condition induced a higher intensity of illusion of movement and a higher sensation of wrist's extension than the Hidden condition (p<0.001 and p<0.001 respectively) than that of the Static condition (p<0.001 and p<0.001 respectively). The Hidden condition also induced a higher intensity of illusion of movement and a higher sensation of wrist's extension than the Static condition (p<0.01 and p<0.01 respectively). The preferred condition to facilitate movement's illusion was the Moving condition (63.3%). CONCLUSIONS: This study demonstrated the importance of carefully selecting a visual feedback to improve the illusion of movement induced by tendon vibration, and the increase of illusion by adding VR visual cues congruent to the illusion of movement. Further work will consist in testing the same hypothesis with stroke patients.


Assuntos
Retroalimentação Sensorial/fisiologia , Ilusões/fisiologia , Movimento/fisiologia , Tendões/fisiologia , Realidade Virtual , Adulto , Idoso , Idoso de 80 Anos ou mais , Sinais (Psicologia) , Voluntários Saudáveis , Humanos , Pessoa de Meia-Idade , Reabilitação do Acidente Vascular Cerebral , Vibração , Adulto Jovem
18.
Nat Commun ; 11(1): 5952, 2020 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-33230227

RESUMO

Cytoplasmic dynein is the primary motor for microtubule minus-end-directed transport and is indispensable to eukaryotic cells. Although each motor domain of dynein contains three active AAA+ ATPases (AAA1, 3, and 4), only the functions of AAA1 and 3 are known. Here, we use single-molecule fluorescence and optical tweezers studies to elucidate the role of AAA4 in dynein's mechanochemical cycle. We demonstrate that AAA4 controls the priming stroke of the motion-generating linker, which connects the dimerizing tail of the motor to the AAA+ ring. Before ATP binds to AAA4, dynein remains incapable of generating motion. However, when AAA4 is bound to ATP, the gating of AAA1 by AAA3 prevails and dynein motion can occur. Thus, AAA1, 3, and 4 work together to regulate dynein function. Our work elucidates an essential role for AAA4 in dynein's stepping cycle and underscores the complexity and crosstalk among the motor's multiple AAA+ domains.


Assuntos
Dineínas do Citoplasma/química , Dineínas do Citoplasma/metabolismo , Domínio AAA , Trifosfato de Adenosina/metabolismo , Dineínas do Citoplasma/genética , Hidrólise , Microtúbulos/metabolismo , Movimento , Mutagênese , Pinças Ópticas , Ligação Proteica , Conformação Proteica , Multimerização Proteica , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo
19.
Cochrane Database Syst Rev ; 11: CD001159, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33238043

RESUMO

BACKGROUND: This review was published originally in 1999 and was updated in 2001, 2002, 2009, 2017, and 2020. Updating was deemed necessary due to the high incidence of hip fractures, the large number of official societies providing recommendations on this condition, the possibility that perioperative peripheral nerve blocks (PNBs) may improve patient outcomes, and the major role that PNBs may play in reducing preoperative and postoperative opioid use for analgesia. OBJECTIVES: To compare PNBs used as preoperative analgesia, as postoperative analgesia, or as a supplement to general anaesthesia versus no nerve block (or sham block) for adults with hip fracture. Outcomes were pain on movement at 30 minutes after block placement, acute confusional state, myocardial infarction, chest infection, death, time to first mobilization, and costs of an analgesic regimen for single-injection blocks. We undertook the update to look for new studies and to update the methods to reflect Cochrane standards. SEARCH METHODS: For the updated review, we searched the following databases: the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 11), in the Cochrane Library; MEDLINE (Ovid SP, 1966 to November 2019); Embase (Ovid SP, 1974 to November 2019); and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (EBSCO, 1982 to November 2019), as well as trial registers and reference lists of relevant articles. SELECTION CRITERIA: We included randomized controlled trials (RCTs) assessing use of PNBs compared with no nerve block (or sham block) as part of the care provided for adults 16 years of age and older with hip fracture.  DATA COLLECTION AND ANALYSIS: Two review authors independently screened new trials for inclusion, assessed trial quality using the Cochrane Risk of Bias-2 tool, and extracted data. When appropriate, we pooled results of outcome measures. We rated the certainty of evidence using the GRADE approach. MAIN RESULTS: We included 49 trials (3061 participants; 1553 randomized to PNBs and 1508 to no nerve block (or sham block)). For this update, we added 18 new trials. Trials were published from 1981 to 2020. Trialists followed participants for periods ranging from 5 minutes to 12 months. The average age of participants ranged from 59 to 89 years. People with dementia were often excluded from the included trials. Additional analgesia was available for all participants. Results of 11 trials with 503 participants show that PNBs reduced pain on movement within 30 minutes of block placement (standardized mean difference (SMD) -1.05, 95% confidence interval (CI) -1.25 to -0.86; equivalent to -2.5 on a scale from 0 to 10; high-certainty evidence). Effect size was proportionate to the concentration of local anaesthetic used (P = 0.0003). Based on 13 trials with 1072 participants, PNBs reduce the risk of acute confusional state (risk ratio (RR) 0.67, 95% CI 0.50 to 0.90; number needed to treat for an additional beneficial outcome (NNTB) 12, 95% CI 7 to 47; high-certainty evidence). For myocardial infarction, there were no events in one trial with 31 participants (RR not estimable; low-certainty evidence). From three trials with 131 participants, PNBs probably reduce the risk for chest infection (RR 0.41, 95% CI 0.19 to 0.89; NNTB 7, 95% CI 5 to 72; moderate-certainty evidence). Based on 11 trials with 617 participants, the effects of PNBs on mortality within six months are uncertain due to very serious imprecision (RR 0.87, 95% CI 0.47 to 1.60; low-certainty evidence). From three trials with 208 participants, PNBs likely reduce time to first mobilization (mean difference (MD) -10.80 hours, 95% CI -12.83 to -8.77 hours; moderate-certainty evidence). One trial with 75 participants indicated there may be a small reduction in the cost of analgesic drugs with a single-injection PNB (MD -4.40 euros, 95% CI -4.84 to -3.96 euros; low-certainty evidence). We identified 29 ongoing trials, of which 15 were first posted or at least were last updated after 1 January 2018.  AUTHORS' CONCLUSIONS: PNBs reduce pain on movement within 30 minutes after block placement, risk of acute confusional state, and probably also reduce the risk of chest infection and time to first mobilization. There may be a small reduction in the cost of analgesic drugs for single-injection PNB. We did not find a difference for myocardial infarction and mortality, but the numbers of participants included for these two outcomes were insufficient. Although randomized clinical trials may not be the best way to establish risks associated with an intervention, our review confirms low risks of permanent injury associated with PNBs, as found by others. Some trials are ongoing, but it is unclear whether any further RCTs should be registered, given the benefits found. Good-quality non-randomized trials with appropriate sample size may help to clarify the potential effects of PNBs on myocardial infarction and mortality.


Assuntos
Fraturas do Quadril/cirurgia , Bloqueio Nervoso/métodos , Manejo da Dor , Idoso , Idoso de 80 Anos ou mais , Anestésicos Locais/administração & dosagem , Anestésicos Locais/efeitos adversos , Confusão/epidemiologia , Confusão/prevenção & controle , Deambulação Precoce , Feminino , Fraturas do Quadril/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Movimento , Infarto do Miocárdio/epidemiologia , Bloqueio Nervoso/efeitos adversos , Medição da Dor , Dor Pós-Operatória/terapia , Nervos Periféricos , Pneumonia/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Infecções Respiratórias/prevenção & controle , Fatores de Tempo
20.
Artigo em Inglês | MEDLINE | ID: mdl-33233328

RESUMO

OBJECTIVE: To assess whether a slackline intervention program improves postural control in children/adolescents with spastic cerebral palsy (CP). DESIGN: Randomized controlled trial. SETTING: Patients' association. PARTICIPANTS: Twenty-seven children/adolescents with spastic CP (9-16 years) were randomly assigned to a slackline intervention (n = 14, 13 ± 3 years) or control group (n = 13, 12 ± 2 years). INTERVENTION: Three slackline sessions per week (30 min/session) for 6 weeks. MAIN OUTCOME MEASURES: The primary outcome was static posturography (center of pressure-CoP-parameters). The secondary outcomes were surface myoelectrical activity of the lower-limb muscles during the posturography test and jump performance (countermovement jump test and Abalakov test). Overall (RPE, >6-20 scale) rating of perceived exertion was recorded at the end of each intervention session. RESULTS: The intervention was perceived as "very light" (RPE = 7.6 ± 0.6). The intervention yielded significant benefits on static posturography (a significant group by time interaction on Xspeed, p = 0.006) and jump performance (a significant group by time interaction on Abalakov test, p = 0.015). CONCLUSIONS: Slackline training improved static postural control and motor skills and was perceived as non-fatiguing in children/adolescents with spastic CP.


Assuntos
Paralisia Cerebral/reabilitação , Transtornos Motores/reabilitação , Movimento/fisiologia , Espasticidade Muscular/reabilitação , Equilíbrio Postural/fisiologia , Treinamento de Resistência/métodos , Adolescente , Criança , Eletromiografia , Exercício Físico , Feminino , Humanos , Masculino , Transtornos Motores/etiologia , Destreza Motora/fisiologia , Resultado do Tratamento
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