2,329 research outputs found
Mixed-Criticality Scheduling with I/O
This paper addresses the problem of scheduling tasks with different
criticality levels in the presence of I/O requests. In mixed-criticality
scheduling, higher criticality tasks are given precedence over those of lower
criticality when it is impossible to guarantee the schedulability of all tasks.
While mixed-criticality scheduling has gained attention in recent years, most
approaches typically assume a periodic task model. This assumption does not
always hold in practice, especially for real-time and embedded systems that
perform I/O. For example, many tasks block on I/O requests until devices signal
their completion via interrupts; both the arrival of interrupts and the waking
of blocked tasks can be aperiodic. In our prior work, we developed a scheduling
technique in the Quest real-time operating system, which integrates the
time-budgeted management of I/O operations with Sporadic Server scheduling of
tasks. This paper extends our previous scheduling approach with support for
mixed-criticality tasks and I/O requests on the same processing core. Results
show the effective schedulability of different task sets in the presence of I/O
requests is superior in our approach compared to traditional methods that
manage I/O using techniques such as Sporadic Servers.Comment: Second version has replaced simulation experiments with real machine
experiments, third version fixed minor error in Equation 5 (missing a plus
sign
Formulation and Stability of an Extemporaneously Compounded Oral Solution of Chlorpromazine HCl
Chlorpromazine is a phenothiazine antipsychotic which is often used in hospice and palliative care to treat hiccups, delirium, and nausea. With the discontinuation of the commercial oral solution concentrate, there is a need to prepare this product by extemporaneous compounding. This study was initiated to identify an easy-to-prepare formulation for the compounding pharmacist. A stability study was also conducted to select the proper storage conditions and establish the beyond-use date. Chlorpromazine HCl powder and the Ora-Sweet® syrup vehicle were used to prepare the 100 mg/mL solution. Once the feasibility was established, a batch of the solution was prepared and packaged in amber plastic prescription bottles for a stability study. These samples were stored at refrigeration (2–8°C) or room temperature (20–25°C) for up to 3 months. At each monthly time point, the samples were evaluated by visual inspection, pH measurement, and high performance liquid chromatography (HPLC). A separate forced stability study was conducted to confirm that the HPLC method was stability indicating. A clear and colorless solution of 100 mg/mL chlorpromazine HCl was obtained by dissolving the drug powder in Ora-Sweet® with moderate agitation. The stability study results indicated that this solution product remained unchanged in visual appearance or pH at both refrigeration and room temperature for up to 3 months. The HPLC results also confirmed that all stability samples retained 93.6–101.4% of initial drug concentration. Chlorpromazine HCl solution 100 mg/mL can be compounded extemporaneously by dissolving chlorpromazine HCl drug powder in Ora-Sweet®. The resulting product is stable for at least three months in amber plastic prescription bottles stored at either refrigeration or room temperature
Enhanced cancer therapy with cold-controlled drug release and photothermal warming enabled by one nanoplatform
Stimuli-responsive nanoparticles hold great promise for drug delivery to improve the safety and efficacy of cancer therapy. One of the most investigated stimuli-responsive strategies is to induce drug release by heating with laser, ultrasound, or electromagnetic field. More recently, cryosurgery (also called cryotherapy and cryoablation), destruction of diseased tissues by first cooling/freezing and then warming back, has been used to treat various diseases including cancer in the clinic. Here we developed a cold-responsive nanoparticle for controlled drug release as a result of the irreversible disassembly of the nanoparticle when cooled to below ∼10 °C. Furthermore, this nanoparticle can be used to generate localized heating under near infrared (NIR) laser irradiation, which can facilitate the warming process after cooling/freezing during cryosurgery. Indeed, the combination of this cold-responsive nanoparticle with ice cooling and NIR laser irradiation can greatly augment cancer destruction both in vitro and in vivo with no evident systemic toxicity
CRKD: Enhanced Camera-Radar Object Detection with Cross-modality Knowledge Distillation
In the field of 3D object detection for autonomous driving, LiDAR-Camera (LC)
fusion is the top-performing sensor configuration. Still, LiDAR is relatively
high cost, which hinders adoption of this technology for consumer automobiles.
Alternatively, camera and radar are commonly deployed on vehicles already on
the road today, but performance of Camera-Radar (CR) fusion falls behind LC
fusion. In this work, we propose Camera-Radar Knowledge Distillation (CRKD) to
bridge the performance gap between LC and CR detectors with a novel
cross-modality KD framework. We use the Bird's-Eye-View (BEV) representation as
the shared feature space to enable effective knowledge distillation. To
accommodate the unique cross-modality KD path, we propose four distillation
losses to help the student learn crucial features from the teacher model. We
present extensive evaluations on the nuScenes dataset to demonstrate the
effectiveness of the proposed CRKD framework. The project page for CRKD is
https://song-jingyu.github.io/CRKD.Comment: Accepted to CVPR 202
Latent Multimodal Functional Graphical Model Estimation
Joint multimodal functional data acquisition, where functional data from
multiple modes are measured simultaneously from the same subject, has emerged
as an exciting modern approach enabled by recent engineering breakthroughs in
the neurological and biological sciences. One prominent motivation to acquire
such data is to enable new discoveries of the underlying connectivity by
combining multimodal signals. Despite the scientific interest, there remains a
gap in principled statistical methods for estimating the graph underlying
multimodal functional data. To this end, we propose a new integrative framework
that models the data generation process and identifies operators mapping from
the observation space to the latent space. We then develop an estimator that
simultaneously estimates the transformation operators and the latent graph.
This estimator is based on the partial correlation operator, which we
rigorously extend from the multivariate to the functional setting. Our
procedure is provably efficient, with the estimator converging to a stationary
point with quantifiable statistical error. Furthermore, we show recovery of the
latent graph under mild conditions. Our work is applied to analyze
simultaneously acquired multimodal brain imaging data where the graph indicates
functional connectivity of the brain. We present simulation and empirical
results that support the benefits of joint estimation
Evidence for active maintenance of inverted repeat structures identified by a comparative genomic approach
Inverted repeats have been found to occur in both prokaryotic and eukaryotic genomes. Usually they are short and some have important functions in various biological processes. However, long inverted repeats are rare and can cause genome instability. Analyses of C. elegans genome identified long, nearly-perfect inverted repeat sequences involving both divergently and convergently oriented homologous gene pairs and complete intergenic sequences. Comparisons with the orthologous regions from the genomes of C. briggsae and C. remanei show that the inverted repeat structures are often far more conserved than the sequences. This observation implies that there is an active mechanism for maintaining the inverted repeat nature of the sequences
A Pilot Chemical and Physical Stability Study of Extemporaneously Compounded Levetiracetam Intravenous Solution
Levetiracetam is a commonly used antiepileptic medication for tumor-related epilepsy. However, the 100 mL intravenous (IV) infusion volume can be burdensome to imminently dying hospice patients. A reduced infusion volume would improve patient tolerability. The purpose of this study was to evaluate the stability of 1000 mg/25 mL (40 mg/mL) levetiracetam IV solution in sodium chloride 0.9%. We prepared levetiracetam 40 mg/mL IV solution and added it to polyvinyl chloride (PVC) bags, polyolefin bags, and polypropylene syringes. Triplicate samples of each product were stored at refrigeration (2–8°C) and analyzed on days 0, 1, 4, 7, and 14. Samples were subjected to visual inspection, pH measurement, and stability-indicating high-performance liquid chromatography (HPLC) analysis. Over the 2-week storage period, there was no significant change in visual appearance or pH for any of the stability samples. The HPLC results confirmed that all stability samples retained 94.2–101.3% of initial drug concentration and no degradation products or leachable material from the packaging materials were observed. We conclude that levetiracetam 1000 mg/25 mL IV solution in sodium chloride 0.9% is physically and chemically stable for up to 14 days under refrigeration in polypropylene syringes, PVC bags, and polyolefin bags
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