Postural instability is a major disabling feature in Parkinson’s disease (PD). We quantified the organization of leg and trunk muscles into synergies stabilizing the center of pressure (COP) ...coordinate within the uncontrolled manifold hypothesis in levodopa-naïve patients with PD and age-matched control subjects. The main hypothesis was that changes in the synergic control of posture are present early in the PD process even before levodopa exposure. Eleven levodopa-naïve patients with PD and 11 healthy controls performed whole-body cyclical voluntary sway tasks and a self-initiated load-release task during standing on a force plate. Surface electromyographic activity in 13 muscles on the right side of the body was analyzed to identify muscle groups with parallel scaling of activation levels (M-modes). Data were collected both before (“off-drug”) and approximately 60 min after the first dose of 25/100 carbidopa/levodopa (“on-drug”). COP-stabilizing synergies were quantified for the load-release task. Levodopa-naïve patients with PD showed no COP-stabilizing synergy “off-drug”, whereas controls showed posture-stabilizing multi-M-mode synergy. “On-drug”, patients with PD demonstrated a significant increase in the synergy index. There were no significant drug effects on the M-mode composition, anticipatory postural adjustments, indices of motor equivalence, or indices of COP variability. The results suggest that levodopa-naïve patients with PD already show impaired posture-stabilizing multi-muscle synergies that may be used as promising behavioral biomarkers for emerging postural disorders in PD. Moreover, levodopa modified synergy metrics differently in these levodopa-naïve patients compared to a previous study of patients on chronic antiparkinsonian medications (Falaki et al. in J Electromyogr Kinesiol 33:20–26, 2017a), suggesting different neurocircuitry involvement.
This paper offers perspectives on the development of low-carbon energy technology in Brazil, pinpointing changes that have occurred since our former publication in 2011. It takes a fresh approach in ...terms of how likely Brazil will achieve its Nationally Determined Contributions Commitments in the energy sector. Many countries have implemented national climate policies to accomplish their pledged NDC and contribute to the temperature objectives of the Paris Agreement on climate change. Based on official reports and databases of energy development projections in Brazil and the socioeconomic context, we discuss what can be expected for the future of the Brazilian energy sector, the probability of implementing selected technologies, and the prospects of reaching the NDC targets for 2025 and 2030. In addition, this paper provides an overview of the current stage of development of these technologies, main directions, and bottlenecks in Brazil. Analyses have shown that the Brazilian renewable matrix tends to remain significant, driven by the development of solar and mostly small hydroelectric power sources, as well as different types of biomass. In addition, the system will include the replacement of thermoelectric plants powered by diesel and fuel oil by natural gas plants. The prospects for Brazil's official energy plan for 2027 are aligned with the reference technology scenario, which represents the business as usual scenario. Despite this, low-carbon technologies could be implemented far beyond the NDC's goals, given the abundance of renewable natural resources in the country.
•Prospects for low-carbon technologies in Brazil are lacking.•RenovaBio Law may promote bioelectricity production from sugarcane bagasse.•Small hydro will play an important role in the achievement of Brazilian NDC for the hydroelectric sector.•Wind power is developing rapidly, but still substantial room for growth.•Solar power is developing slower than expected.
We explored the origin of the impaired control of action stability in Parkinson’s disease (PD) by testing levodopa-naïve PD patients to disambiguate effects of PD from possible effects of long-term ...exposure to levodopa. Thirteen levodopa-naïve PD patients and 13 controls performed single- and multi-finger force production tasks, including producing a self-paced quick force pulse into a target. A subgroup of patients (
n
= 10) was re-tested about 1 h after the first dose of levodopa. Compared to controls, PD patients showed lower maximal forces and synergy indices stabilizing total force (reflecting the higher inter-trial variance component affecting total force). In addition, PD patients showed a trend toward shorter anticipatory synergy adjustments (a drop in the synergy index in preparation to a quick action) and larger non-motor equivalent finger force deviations. Lower maximal force, higher unintentional force production (enslaving) and higher inter-trial variance indices occurred in PD patients after one dosage of levodopa. We conclude that impairment in synergies is present in levodopa-naïve patients, mainly in indices reflecting stability (synergy index), but not agility (anticipatory synergy adjustments). A single dose of levodopa, however, did not improve synergy indices, as it did in PD patients on chronic anti-PD medication, suggesting a different mechanism of action. The results suggest that indices of force-stabilizing synergies may be used as an early behavioral sign of PD, although it may not be sensitive to acute drug effects in drug-naïve patients.
The framework of the uncontrolled manifold (UCM) hypothesis was used to explore variables related to stability of task performance in the two hands of young healthy individuals. Fourteen young adults ...performed four-finger accurate constant force production tasks interrupted by a voluntary quick force pulse production and by an externally imposed displacement of all fingers. Three groups of variables were used to quantify stability of steady force production: (1) indices of the inter-trial variance were computed within the UCM and orthogonal to the UCM; (2) indices of motor equivalence were computed between steady-state intervals separated by the force pulse and by the finger-lifting episode; and (3) referent coordinate and apparent stiffness were computed using the data during the ascending phase of the finger-lifting episode. In another task, the subjects performed accurate constant force production with visual feedback removal after the 8th second, and the drop in the total force after the removal was computed. There were differences between the right and left hand in some outcome variables such as variance within the UCM, and the timing of anticipatory synergy adjustments prior to the force pulse, consistent with the dynamic dominance hypothesis. There were significant correlations between the two hands for indices that were unrelated to accuracy of performance: variance within the UCM, index of motor equivalence, referent coordinate, apparent stiffness, and the drop of total force after visual feedback removal. We interpret these findings within the concept of stability–optimality trade-off. In particular, we conclude that individual subjects select particular, person-specific solutions within the spectrum allowed by the explicit task constraints, and this choice is consistent between the two hands. We conclude with a hypothesis that selecting specific solutions within the stability–optimality trade-off may represent an individual’s personal preference consistent between the two hands.
Condition monitoring of synchronous generators through non-invasive methods is widely requested by maintenance teams for not interfering the machine operation. Among the techniques used, external ...magnetic field monitoring is a recent strategy with great potential for detecting incipient faults. In this context, this paper proposes the application of a simple strategy with low computational cost to process data of external magnetic field time derivative signals for the purposes of condition monitoring and fault detection in synchronous machines. The information of interest is extracted from changes in the magnetic signature of the synchronous generator, obtained from frequency spectra of monitored signals using induction magnetic field sensors. The process forms a set of time series that reflects constructive and operational characteristics of the machine. The Shewhart control chart method is applied for anomaly detection in these time series, allowing the detection of changes in the machine magnetic signature. This method is employed in an algorithm for continuous condition monitoring of synchronous generators, presenting as output a global change indicator for the multivariable problem associated with magnetic signature monitoring. Correlation matrices are used to improve the algorithm response, filtering series with similar variation patterns associated with detected events. The proposed method is validated through tests on an experimental bench that allows the controlled imposition of faults in a synchronous generator. The proposed global change indicator allows the automatic detection of stator and rotor faults with the machine synchronized with the commercial power grid. The proposed methodology is also applied on data obtained from an equipment installed in a 305 MVA synchronous generator of a hydroelectric power plant where the evolution of an incipient fault, i.e., a mechanical vibration fault, has been detected.
A number of analyses associated with the uncontrolled manifold (UCM) hypothesis have been used recently to investigate stability of actions across populations. We explored whether some of those ...methods have an advantage for clinical studies because they require fewer trials to achieve consistent findings. We compared the number of trials needed for the analysis of inter-trial variance, analysis of motor equivalence, and analysis in the space of referent coordinates. Young healthy adults performed four-finger accurate force production tasks under visual feedback with the right (dominant) and left hand over three days. Three methods analytical (M1), experimental (M2), and cumulative mean (M3) methods were used to define the minimal number of trials required to reach certain statistical criteria. Two of these methods, M1 and M2, showed qualitatively similar results. Fewer trials (M1: 5–13, M2: 4–10) were needed for analysis of motor equivalence compared to inter-trial variance analysis (M1: 14–24, M2: 10–14). The third method (M3) showed no major differences among the outcome variables. The index of synergy in the inter-trial variance analysis required a very small number of trials (M1, M2: 2–4). Variables related to referent coordinates required only a few trials (under 3), whereas the synergy index in this analysis required the largest number of trials (M1: 24–34, M2: 12–16). This is the first study to quantify the number of trials needed for UCM-based methods of assessing motor coordination broadly used in clinical studies. Clinical studies can take advantage of specific recommendations based on the current data regarding the number of trials needed for each analysis thus allowing minimizing the test session duration without compromising data reliability.
Objective
We aimed to investigate the impact of applying the 2019 European Alliance of Associations for Rheumatology (EULAR)/American College of Rheumatology (ACR) classification criteria for ...systemic lupus erythematosus (SLE) in a previously described cohort of women with undifferentiated connective tissue disease (UCTD).
Methods
This study included 133 women with UCTD. At the time of inclusion into the study, none of the patients met any classification criteria for other defined systemic connective tissue disease.
Results
When applying the 2019 EULAR/ACR classification criteria to the cohort, 22 patients (17%) fulfilled the classification criteria for SLE. Patients classified as having SLE had significantly higher frequencies of mucocutaneous manifestations (23% versus 5%; P = 0.007), arthritis (59% versus 17%; P < 0.001), isolated urine abnormalities (18% versus 1%; P < 0.001), and highly specific antibodies (50% versus 15%; P < 0.001) compared to the other patients with UCTD. At follow‐up, these patients were statistically significantly more likely to also meet the 1997 ACR revised SLE criteria and the Systemic Lupus International Collaborating Clinics (SLICC) criteria (18.2% versus 1.8%; P < 0.001) compared to the other UCTD patients.
Patients who were diagnosed as having SLE according to the ACR 1997 update of the SLE revised criteria and the SLICC criteria during the follow‐up scored higher on outcome measures when classified as having SLE according to the new 2019 EULAR/ACR classification criteria when compared to the other patients with UCTD (mean ± SD score 8.3 ± 3.7 versus 4.5 ± 4; P < 0.05).
Conclusion
When applying the 2019 EULAR/ACR criteria for SLE in a cohort of patients with UCTD, we observed that in up to 17% of cases the original classification could be challenged. New implementation will help to identify earlier patients at higher risk of developing more severe CTD manifestations.
A Gram-staining-negative, oxidase-positive, strictly aerobic rod-shaped bacterium, designated strain PT1.sup.T, was isolated from the laboratory-reared larvae of the sea cucumber Apostichopus ...japonicus. A phylogenetic analysis based on the 16S rRNA gene nucleotide sequences revealed that PT1.sup.T was closely related to Neptuniibacter marinus ATR 1.1.sup.T (= CECT 8938.sup.T = DSM 100783.sup.T) and Neptuniibacter caesariensis MED92.sup.T (= CECT 7075.sup.T = CCUG 52065.sup.T) showing 98.2% and 98.1% sequence similarity, respectively. However, the average nucleotide identity (ANI) and in silico DNA-DNA hybridization (DDH) values among these three strains were 72.0%-74.8% and 18.3%-19.5% among related Neptuniibacter species, which were below 95% and 70%, respectively, confirming the novel status of PT1.sup.T . The average amino acid identity (AAI) values of PT1.sup.T showing 74-77% among those strains indicated PT1.sup.T is a new species in the genus Neptuniibacter. Based on the genome-based taxonomic approach, Neptuniibacter victor sp. nov. is proposed for PT1.sup.T . The type strain is PT1.sup.T (JCM 35563.sup.T = LMG 32868.sup.T).
The Great Barrier Reef (GBR) provides a globally significant demonstration of the effectiveness of large-scale networks of marine reserves in contributing to integrated, adaptive management. ...Comprehensive review of available evidence shows major, rapid benefits of no-take areas for targeted fish and sharks, in both reef and nonreef habitats, with potential benefits for fisheries as well as biodiversity conservation. Large, mobile species like sharks benefit less than smaller, site-attached fish. Critically, reserves also appear to benefit overall ecosystem health and resilience: outbreaks of coral-eating, crown-of-thorns starfish appear less frequent on no-take reefs, which consequently have higher abundance of coral, the very foundation of reef ecosystems. Effective marine reserves require regular review of compliance: fish abundances in no-entry zones suggest that even no-take zones may be significantly depleted due to poaching. Spatial analyses comparing zoning with seabed biodiversity or dugong distributions illustrate significant benefits from application of best-practice conservation principles in data-poor situations. Increases in the marine reserve network in 2004 affected fishers, but preliminary economic analysis suggests considerable net benefits, in terms of protecting environmental and tourism values. Relative to the revenue generated by reef tourism, current expenditure on protection is minor. Recent implementation of an Outlook Report provides regular, formal review of environmental condition and management and links to policy responses, key aspects of adaptive management. Given the major threat posed by climate change, the expanded network of marine reserves provides a critical and cost-effective contribution to enhancing the resilience of the Great Barrier Reef.
Background
Cervical transcutaneous spinal cord stimulation (tSCS) is a rehabilitation tool which has been used to promote upper‐limb motor recovery after spinal cord injury. Importantly, optimizing ...sensory fiber activation at specific spinal segments could enable activity‐dependent neuromodulation during rehabilitation.
Methods
An anatomically realistic cervical tSCS computational model was used to analyze the activation of α‐motor and Aα‐sensory fibers at C7 and C8 spinal segments using nine cathode electrode configurations. Specifically, the cathode was simulated at three vertebral level positions: C6, C7, and T1; and in three sizes: 5.0 × 5.0, 3.5 × 3.5, and 2.5 × 2.5 cm2, while the anode was on the anterior neck. Finite element method was used to estimate the electric potential distribution along α‐motor and Aα‐sensory fibers, and computational models were applied to simulate the fiber membrane dynamics during tSCS. The minimum stimulation intensity necessary to activate the fibers (activation threshold) was estimated and compared across cathode configurations in an effort to optimize sensory fiber activation.
Results
Our results showed that nerve fibers at both C7 and C8 spinal segments were recruited at lower stimulation intensities when the cathode was positioned over the C7 or T1 vertebra compared with the C6 position. Sensory fibers were activated at lower stimulation intensities using smaller electrodes, which could also affect the degree of nerve fiber activation across different positions. Importantly, Aα‐sensory fibers were consistently recruited before α‐motor fibers.
Conclusions
These results imply that cathode positioning could help optimize preferential activation of hand muscles during cervical tSCS.
In this study, we concluded that:
The C7 or T1 cathode positions optimized the activation of sensory fibers projecting to the hand muscles.
Smaller cathodes required less intensity to activate the fibers, which could affect the degree of activation across different positions.
Sensory fibers were always recruited at lower stimulation intensities compared with motor fibers for all cathode configurations.
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