125 research outputs found
Motor improvements enabled by spinal cord stimulation combined with physical training after spinal cord injury: Review of experimental evidence in animals and humans
Electrical spinal cord stimulation (SCS) has been gaining momentum as a potential therapy for motor paralysis in consequence of spinal cord injury (SCI). Specifically, recent studies combining SCS with activity-based training have reported unprecedented improvements in motor function in people with chronic SCI that persist even without stimulation. In this work, we first provide an overview of the critical scientific advancements that have led to the current uses of SCS in neurorehabilitation: e.g. the understanding that SCS activates dormant spinal circuits below the lesion by recruiting large-to-medium diameter sensory afferents within the posterior roots. We discuss how this led to the standardization of implant position which resulted in consistent observations by independent clinical studies that SCS in combination with physical training promotes improvements in motor performance and neurorecovery. While all reported participants were able to move previously paralyzed limbs from day 1, recovery of more complex motor functions was gradual, and the timeframe for first observations was proportional to the task complexity. Interestingly, individuals with SCI classified as AIS B and C regained motor function in paralyzed joints even without stimulation, but not individuals with motor and sensory complete SCI (AIS A). Experiments in animal models of SCI investigating the potential mechanisms underpinning this neurorecovery suggest a synaptic reorganization of cortico-reticulo-spinal circuits that correlate with improvements in voluntary motor control. Future experiments in humans and animal models of paralysis will be critical to understand the potential and limits for functional improvements in people with different types, levels, timeframes, and severities of SCI
Ising antiferromagnet with ultracold bosonic mixtures confined in a harmonic trap
We present accurate results based on Quantum Monte Carlo simulations of
two-component bosonic systems on a square lattice and in the presence of an
external harmonic confinement. Starting from hopping parameters and interaction
strengths which stabilize the Ising antiferromagnetic phase in the homogeneous
case and at half integer filling factor, we study how the presence of the
harmonic confinement challenge the realization of such phase. We consider
realistic trapping frequencies and number of particles, and establish under
which conditions, i.e. total number of particles and population imbalance, the
antiferromagnetic phase can be observed in the trap.Comment: 4 pages, 2 figures, accepted for publication on PRA as a Rapid
Communication. The present version contains lighter low resolution images.
For High resolution version please refer to Journa
A Machine Learning-oriented Survey on Tiny Machine Learning
The emergence of Tiny Machine Learning (TinyML) has positively revolutionized
the field of Artificial Intelligence by promoting the joint design of
resource-constrained IoT hardware devices and their learning-based software
architectures. TinyML carries an essential role within the fourth and fifth
industrial revolutions in helping societies, economies, and individuals employ
effective AI-infused computing technologies (e.g., smart cities, automotive,
and medical robotics). Given its multidisciplinary nature, the field of TinyML
has been approached from many different angles: this comprehensive survey
wishes to provide an up-to-date overview focused on all the learning algorithms
within TinyML-based solutions. The survey is based on the Preferred Reporting
Items for Systematic Reviews and Meta-Analyses (PRISMA) methodological flow,
allowing for a systematic and complete literature survey. In particular,
firstly we will examine the three different workflows for implementing a
TinyML-based system, i.e., ML-oriented, HW-oriented, and co-design. Secondly,
we propose a taxonomy that covers the learning panorama under the TinyML lens,
examining in detail the different families of model optimization and design, as
well as the state-of-the-art learning techniques. Thirdly, this survey will
present the distinct features of hardware devices and software tools that
represent the current state-of-the-art for TinyML intelligent edge
applications. Finally, we discuss the challenges and future directions.Comment: Article currently under review at IEEE Acces
How central inputs and force and velocity feedbacks determine motoneurons activity during voluntary hand movements
Effect of allogeneic intraoperative blood transfusion on survival in patients treated with radical cystectomy for nonmetastatic bladder cancer: Results from a single high-volume institution
Transfusion has been related to poor survival after surgery in several cancers. Recently, timing of transfusion has been proposed as crucial in the determination of poor survival expectanies after surgery, in fact, intra- operative but not postoperative transfusion were found to be related. We confirmed these findings in patients who underwent radical cystectomy because of bladder cancer; physicians should avoid use of transfusion intraoperatively.
Background: Previous studies have demonstrated that perioperative blood transfusion (BT) is associated with a significantly increased risk of cancer recurrence and mortality after radical cystectomy (RC). Recently, it was shown for the first time that intraoperative transfusion has a detrimental effect on cancer survival. The aim of the current study was to validate this finding in a single European institution. Patients and Methods: The study focused on 1490 consecutive nonmetastatic bladder cancer patients treated with RC at a single tertiary care referral center between January 1990 and August 2013. KaplaneMeier analyses and Cox regression analyses were used to assess the effect of timing of BT administration (no transfusion vs. intraoperative transfusion vs. postoperative transfusion vs. intra- operative and postoperative transfusion) on cancer-specific mortality (CSM), overall mortality (OM), and disease recurrence. Results: Mean age at the time of RC was 67 years. Overall, 322 (21.6%) patients received intraoperative BT and 97 (6.5%) received postoperative BT. At a mean follow-up time of 125 months (median, 110 months), the 5- and 10-year CSM rate was 846 (58%) and 715 (48%), respectively. In multivariable analyses patients who received intraoperative BT had greater risk of disease recurrence (hazard ratio [HR], 1.24; P .2). Conclusion: Our study confirms that intraoperative, but not postoperative BT, are related to a detrimental effect on survival after RC. These results should be take into account by physicians to administer BT using the correct timing
Disentangled Latent Spaces Facilitate Data-Driven Auxiliary Learning
In deep learning, auxiliary objectives are often used to facilitate learning
in situations where data is scarce, or the principal task is extremely complex.
This idea is primarily inspired by the improved generalization capability
induced by solving multiple tasks simultaneously, which leads to a more robust
shared representation. Nevertheless, finding optimal auxiliary tasks that give
rise to the desired improvement is a crucial problem that often requires
hand-crafted solutions or expensive meta-learning approaches. In this paper, we
propose a novel framework, dubbed Detaux, whereby a weakly supervised
disentanglement procedure is used to discover new unrelated classification
tasks and the associated labels that can be exploited with the principal task
in any Multi-Task Learning (MTL) model. The disentanglement procedure works at
a representation level, isolating a subspace related to the principal task,
plus an arbitrary number of orthogonal subspaces. In the most disentangled
subspaces, through a clustering procedure, we generate the additional
classification tasks, and the associated labels become their representatives.
Subsequently, the original data, the labels associated with the principal task,
and the newly discovered ones can be fed into any MTL framework. Extensive
validation on both synthetic and real data, along with various ablation
studies, demonstrate promising results, revealing the potential in what has
been, so far, an unexplored connection between learning disentangled
representations and MTL. The code will be made publicly available upon
acceptance.Comment: Under review in Pattern Recognition Letter
Correction to : "Experimental Validation of a Hybrid Computational Model for Selective Stimulation Using Transverse Intrafascicular Multichannel Electrodes"
Neonatal Adaptation Issues After Maternal Exposure to Prescription Drugs: Withdrawal Syndromes and Residual Pharmacological Effects
Exposure to drugs during pregnancy has the potential to harm offspring. Teratogenic effects are the most feared adverse outcomes in newborns; however, a wide spectrum of less known, usually reversible and often acute, neonatal adverse events can also occur due to drug intake by mothers during pregnancy, particularly in close proximity to delivery. This narrative review is aimed at the description of drugs and drug classes for which licit maternal use in the predelivery period has been associated with neonatal non-teratogenic disorders. For each drug class, epidemiology, clinical features, biological mechanism and management of these adverse reactions have been discussed in detail. Although these adverse reactions have been described mainly for substances used illicitly for recreational purposes, several prescription drugs have also been involved; these include mainly psychotropic medications such as opioids, antidepressants, antiepileptics and antipsychotics. These effects can be partly explained by withdrawal syndromes (defined also as 'neonatal abstinence syndrome') caused by the delivery-related discontinuation of the drug disposition from the mother to the fetus, with symptoms that may include feeding disorders, tremors, irritability, hypotonia/hypertonia, vomiting and persistent crying, occurring a few hours to 1Â month after delivery. Otherwise, neonatal neurological and behavioral effects can also be caused by a residual pharmacological effect due to an accumulation of the drug in the blood and tissues of the newborn, with various symptoms related to the toxic effects of the specific drug class, usually developing a few hours after birth. With few exceptions, validated protocols for the assessment and management of withdrawal or residual pharmacological effects of these drugs in neonates are often lacking or incomplete. Spontaneous reporting of these adverse reactions seems limited, although it might represent a useful tool for improving our knowledge about drug-induced neonatal syndromes
NEPHRON-SPARING SURGERY PROTECTS FROM CHRONIC KIDNEY DISEASE RELATIVE TO RADICAL NEPHRECTOMY BUT DOES NOT IMPACT ON OTHER-CAUSES MORTALITY: LONGTERM (MORE THAN 10 YEARS) SURVIVAL AND FUNCTIONAL OUTCOMES IN PATIENTS WITH A T1A-T1B RENAL MASS
Clinical differences among the elderly admitted to the emergency department for accidental or unexplained falls and syncope
It is difficult to distinguish unexplained falls (UFs) from accidental falls (AFs) or syncope in older people. This study was designed to compare patients referred to the emergency department (ED) for AFs, UFs or syncope. Data from a longitudinal study on adverse drug events diagnosed at the ED (ANCESTRAL-ED) in older people were analyzed in order to select cases of AF, syncope, or UF. A total of 724 patients (median age: 81.0 [65–105] years, 66.3% female) were consecutively admitted to the ED (403 AF, 210 syncope, and 111 UF). The number of psychotropic drugs was the only significant difference in patients with AF versus those with UF (odds ratio [OR] 1.44; 95% confidence interval 1.17–1.77). When comparing AF with syncope, female gender, musculoskeletal diseases, dementia, and systolic blood pressure >110 mmHg emerged as significantly associated with AF (OR 0.40 [0.27–0.58], 0.40 [0.24–0.68], 0.35 [0.14–0.82], and 0.31 [0.20–0.49], respectively), while valvulopathy and the number of antihypertensive drugs were significantly related to syncope (OR 2.51 [1.07–5.90] and 1.24 [1.07–1.44], respectively). Upon comparison of UF and syncope, the number of central nervous system drugs, female gender, musculoskeletal diseases, and SBP >110 mmHg were associated with UF (OR 0.65 [0.50–0.84], 0.52 [0.30–0.89], 0.40 [0.20–0.77], and 0.26 [0.13–0.55]), respectively. These results indicate specific differences, in terms of demographics, medical/pharmacological history, and vital signs, among older patients admitted to the ED for AF and syncope. UF was associated with higher use of psychotropic drugs than AF. Our findings could be helpful in supporting a proper diagnostic process when evaluating older patients after a fall
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