297 research outputs found
LMExplainer: a Knowledge-Enhanced Explainer for Language Models
Large language models (LMs) such as GPT-4 are very powerful and can process
different kinds of natural language processing (NLP) tasks. However, it can be
difficult to interpret the results due to the multi-layer nonlinear model
structure and millions of parameters. Lack of understanding of how the model
works can make the model unreliable and dangerous for everyday users in
real-world scenarios. Most recent works exploit the weights of attention to
provide explanations for model predictions. However, pure attention-based
explanation is unable to support the growing complexity of the models, and
cannot reason about their decision-making processes. Thus, we propose
LMExplainer, a knowledge-enhanced interpretation module for language models
that can provide human-understandable explanations. We use a knowledge graph
(KG) and a graph attention neural network to extract the key decision signals
of the LM. We further explore whether interpretation can also help AI
understand the task better. Our experimental results show that LMExplainer
outperforms existing LM+KG methods on CommonsenseQA and OpenBookQA. We also
compare the explanation results with generated explanation methods and
human-annotated results. The comparison shows our method can provide more
comprehensive and clearer explanations. LMExplainer demonstrates the potential
to enhance model performance and furnish explanations for the reasoning
processes of models in natural language
On Geodesically Convex Formulations for the Brascamp-Lieb Constant
We consider two non-convex formulations for computing the optimal constant in the Brascamp-Lieb inequality corresponding to a given datum and show that they are geodesically log-concave on the manifold of positive definite matrices endowed with the Riemannian metric corresponding to the Hessian of the log-determinant function. The first formulation is present in the work of Lieb [Lieb, 1990] and the second is new and inspired by the work of Bennett et al. [Bennett et al., 2008]. Recent work of Garg et al. [Ankit Garg et al., 2017] also implies a geodesically log-concave formulation of the Brascamp-Lieb constant through a reduction to the operator scaling problem. However, the dimension of the arising optimization problem in their reduction depends exponentially on the number of bits needed to describe the Brascamp-Lieb datum. The formulations presented here have dimensions that are polynomial in the bit complexity of the input datum
Acute anti-allodynic action of gabapentin in dorsal horn and primary somatosensory cortex: Correlation of behavioural and physiological data
Neuropathic pain is a debilitating consequence of neuronal injury or disease. Although first line treatments
include the alpha-2-delta (a2d)-ligands, pregabalin and gabapentin (GBP), the mechanism of their
anti-allodynic action is poorly understood. One specific paradox is that GBP relieves signs of neuropathic
pain in animal models within 30min of an intraperitoneal (IP) injection yet its actions in vitro on spinal
dorsal horn or primary afferent neurons take hours to develop. We found, using confocal Ca2þ imaging,
that substantia gelatinosa neurons obtained ex vivo from rats subjected to sciatic chronic constriction
injury (CCI) were more excitable than controls. We confirmed that GBP (100 mg/kg) attenuated mechanical
allodynia in animals subject to CCI within 30min of IP injection.Substantia gelatinosa neurons
obtained ex vivo from these animals no longer displayed CCI-induced increased excitability.
Electrophysiological analysis of substantia gelatinosa neurons ex vivo suggest that rapidly developing
in vivo anti-allodynic effects of GBP i) are mediated intracellularly, ii) involve actions on the neurotransmitter
release machinery and iii) depend on decreased excitatory synaptic drive to excitatory
neurons without major actions on inhibitory neurons or on intrinsic neuronal excitability. Experiments
using in vivo Ca2þ imaging showed that 100 mg/kg GBP also suppressed the response of the S1 somatosensory
cortex of CCI rats, but not that of control rats, to vibrotactile stimulation.
Since the level of a2d1 protein is increased in primary afferent fibres after sciatic CCI, we suggest this
dictates the rate of GBP action; rapidly developing actions can only be seen when a2d1 levels are
elevated
HIPAD - A Hybrid Interior-Point Alternating Direction algorithm for knowledge-based SVM and feature selection
We consider classification tasks in the regime of scarce labeled training
data in high dimensional feature space, where specific expert knowledge is also
available. We propose a new hybrid optimization algorithm that solves the
elastic-net support vector machine (SVM) through an alternating direction
method of multipliers in the first phase, followed by an interior-point method
for the classical SVM in the second phase. Both SVM formulations are adapted to
knowledge incorporation. Our proposed algorithm addresses the challenges of
automatic feature selection, high optimization accuracy, and algorithmic
flexibility for taking advantage of prior knowledge. We demonstrate the
effectiveness and efficiency of our algorithm and compare it with existing
methods on a collection of synthetic and real-world data.Comment: Proceedings of 8th Learning and Intelligent OptimizatioN (LION8)
Conference, 201
Geometric matrix midranges
We define geometric matrix midranges for positive definite Hermitian matrices and study the midrange problem from a number of perspectives. Special attention is given to the midrange of two positive definite matrices before considering the extension of the problem to matrices. We compare matrix midrange statistics with the scalar and vector midrange problem and note the special significance of the matrix problem from a computational standpoint. We also study various aspects of geometric matrix midrange statistics from the viewpoint of linear algebra, differential geometry and convex optimization.ECH2020 EUROPEAN RESEARCH COUNCIL (ERC) (670645
Child feces disposal practices in rural Orissa: a cross sectional study.
BACKGROUND: An estimated 2.5 billion people worldwide lack access to improved sanitation facilities. While large-scale programs in some countries have increased latrine coverage, they sometimes fail to ensure optimal latrine use, including the safe disposal of child feces, a significant source of exposure to fecal pathogens. We undertook a cross-sectional study to explore fecal disposal practices among children in rural Orissa, India in villages where the Government of India's Total Sanitation Campaign had been implemented at least three years prior to the study. METHODS AND FINDINGS: We conducted surveys with heads of 136 households with 145 children under 5 years of age in 20 villages. We describe defecation and feces disposal practices and explore associations between safe disposal and risk factors. Respondents reported that children commonly defecated on the ground, either inside the household (57.5%) for pre-ambulatory children or around the compound (55.2%) for ambulatory children. Twenty percent of pre-ambulatory children used potties and nappies; the same percentage of ambulatory children defecated in a latrine. While 78.6% of study children came from 106 households with a latrine, less than a quarter (22.8%) reported using them for disposal of child feces. Most child feces were deposited with other household waste, both for pre-ambulatory (67.5%) and ambulatory (58.1%) children. After restricting the analysis to households owning a latrine, the use of a nappy or potty was associated with safe disposal of feces (OR 6.72, 95%CI 1.02-44.38) though due to small sample size the regression could not adjust for confounders. CONCLUSIONS: In the area surveyed, the Total Sanitation Campaign has not led to high levels of safe disposal of child feces. Further research is needed to identify the actual scope of this potential gap in programming, the health risk presented and interventions to minimize any adverse effect
Boring bivalve traces in modern reef and deeper-water macroid and rhodolith beds
Macroids and rhodoliths, made by encrusting acervulinid foraminifera and coralline algae, are widely recognized as
bioengineers providing relatively stable microhabitats and increasing biodiversity for other species. Macroid and
rhodolith beds occur in different depositional settings at various localities and bathymetries worldwide. Six case
studies of macroid/rhodolith beds from 0 to 117m water depth in the Pacific Ocean (northern Central Ryukyu
Islands, French Polynesia), eastern Australia (Fraser Island, One Tree Reef, Lizard Island), and the Mediterranean Sea
(southeastern Spain) show that nodules in the beds are perforated by small-sized boring bivalve traces
(Gastrochanolites). On average, boring bivalve shells (gastrochaenids and mytilids) are more slender and smaller than
those living inside shallow-water rocky substrates. In the Pacific, Gastrochaena cuneiformis, Gastrochaena sp., Leiosolenus
malaccanus, L. mucronatus, L. spp., and Lithophaga/Leiosolenus sp., for the first time identified below 20m water depth,
occur as juvenile forms along with rare small-sized adults. In deep-water macroids and rhodoliths the boring bivalves
are larger than the shallower counterparts in which growth of juveniles is probably restrained by higher overturn rates
of host nodules. In general, most boring bivalves are juveniles that grew faster than the acervulinid foraminiferal and
coralline red algal hosts and rarely reached the adult stage. As a consequence of phenotypic plasticity, small-sized
adults with slow growth rates coexist with juveniles. Below wave base macroids and rhodoliths had the highest
amounts of bioerosion, mainly produced by sponges and polychaete worms. These modern observations provide
bases for paleobiological inferences in fossil occurrences.Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT)
Japan Society for the Promotion of Science
Grants-in-Aid for Scientific Research (KAKENHI)
25247083Erasmus+FAR2012-2017FIR2016FIR2018PRIN "Biotic resilience to global change: biomineralization of planktonic and benthic calcifiers in the past, present and future"
2017RX9XXXYBioMed Central-Prepay Membership at the University of FerraraJunta de AndalucÃa
RNM 190Committee on ResearchMuseum of PaleontologyDepartment of Integrative Biology, UC BerkeleyUC Pacific Rim Projec
A regularized matrix factorization approach to induce structured sparse-low-rank solutions in the EEG inverse problem
Unmappable ventricular tachycardia after an old myocardial infarction. Long-term results of substrate modification in patients with an implantable cardioverter defibrillator
Purpose The frequent occurrence of ventricular tachycardia can create a serious problem in patients with an implantable cardioverter defibrillator. We assessed the long-term efficacy of catheter-based substrate modification using the voltage mapping technique of infarct-related ventricular tachycardia and recurrent device therapy. Methods The study population consisted of 27 consecutive patients (age 68 +/- 8 years, 25 men, mean left ventricular ejection fraction 31 +/- 9%) with an old myocardial infarction and multiple and/or hemodynamically not tolerated ventricular tachycardia necessitating repeated device therapy. A total of 31 substrate modification procedures were performed using the three-dimensional electroanatomical mapping system. Patients were followed up for a median of 23.5 (interquartile range 6.5-53.2) months before and 37.8 (interquartile range 11.7-71.8) months after ablation. Antiarrhythmic drugs were not changed after the procedure, and were stopped 6 to 9 months after the procedure in patients who did not show ventricular tachycardia recurrence. Results Median ventricular tachycardias were 1.6 (interquartile range 0.7-6.7) per month before and 0.2 (interquartile range 0.00-1.3) per month after ablation (P = 0.006). Nine ventricular fibrillation episodes were registered in seven patients before and two after ablation (P = 0.025). Median antitachycardia pacing decreased from 1.6 (interquartile range 0.01-5.5) per month before to 0.18 (interquartile range 0.00-1.6) per month after ablation (P = 0.069). Median number of shocks decreased from 0.19 (interquartile range 0.04-0.81) per month before to 0.00 (interquartile range 0.00-0.09) per month after ablation (P = 0.001). One patient had a transient ischemic attack during the procedure, and another developed pericarditis. Nine patients died during follow-up, eight patients due to heart failure and one patient during valve surgery. Conclusion Catheter-based substrate modification using voltage mapping results in a long-lasting reduction of cardioverter defibrillator therapy in patients with multiple and/or hemodynamically not tolerated infarct-related ventricular tachyarrhythmia
A systematic review, meta-analysis, and meta-regression of the impact of diurnal intermittent fasting during Ramadan on body weight in healthy subjects aged 16Â years and above
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