ACTS in Need: Automatic Configuration Tuning with Scalability Guarantees

To support the variety of Big Data use cases, many Big Data related systems expose a large number of user-specifiable configuration parameters. Highlighted in our experiments, a MySQL deployment with well-tuned configuration parameters achieves a peak throughput as 12 times much as one with the default setting. However, finding the best setting for the tens or hundreds of configuration parameters is mission impossible for ordinary users. Worse still, many Big Data applications require the support of multiple systems co-deployed in the same cluster. As these co-deployed systems can interact to affect the overall performance, they must be tuned together. Automatic configuration tuning with scalability guarantees (ACTS) is in need to help system users. Solutions to ACTS must scale to various systems, workloads, deployments, parameters and resource limits. Proposing and implementing an ACTS solution, we demonstrate that ACTS can benefit users not only in improving system performance and resource utilization, but also in saving costs and enabling fairer benchmarking

Architectures and Circuit Techniques for High-Performance Field-Programmable CMOS Software Defined Radios

Next-generation wireless communication systems put more stringent performance requirements on the wireless RF receiver circuits. Sensitivity, linearity, bandwidth and power consumption are some of the most important specifications that often face tightly coupled tradeoffs between them. To increase the data throughput, a large number of fragmented spectrums are being introduced to the wireless communication standards. Carrier aggregation technology needs concurrent communication across several non-contiguous frequency bands, which results in a rapidly growing number of band combinations. Supporting all the frequency bands and their aggregation combinations increases the complexity of the RF receivers. Highly flexible software defined radio (SDR) is a promising technology to address these applications scenarios with lower complexity by relaxing the specifications of the RF filters or eliminating them. However, there are still many technology challenges with both the receiver architecture and the circuit implementations. The performance requirements of the receivers can also vary across different application scenario and RF environments. Field-programmable dynamic performance tradeoff can potentially reduce the power consumption of the receiver. In this dissertation, we address the performance enhancement challenges in the wideband SDRs by innovations at both the circuit building block level and the receiver architecture level. A series of research projects are conducted to push the state-of-the-art performance envelope and add features such as field-programmable performance tradeoff and concurrent reception. The projects originate from the concept of thermal noise canceling techniques and further enhance the RF performance and add features for more capable SDR receivers. Four generations of prototype LNA or receiver chips are designed, and each of them pushes at least one aspect of the RF performance such as bandwidth, linearity, and NF. A noise-canceling distributed LNA breaks the tradeoff between NF and RF bandwidth by introducing microwave circuit techniques from the distributed amplifiers. The LNA architecture uniquely provides ultra high bandwidth and low NF at low frequencies. A family of field-programmable LNA realized field-programmable performance tradeoff with current-reuse programmable transconductance cells. Interferer-reflecting loops can be applied around the LNAs to improve their input linearity by rejecting the out-of-band interferers with a wideband low in- put impedance. A low noise transconductance amplifier (LNTA) that operates in class-AB-C is invented to can handle rail-to-rail out-of-band blocker without saturation. Class-AB and class-C transconductors form a composite amplifier to increase the linear range of the input voltage. A new antenna interface named frequency-translational quadrature-hybrid (FTQH) breaks the input impedance matching requirement of the LNAs by introducing quadrature hybrid couplers to the CMOS RFIC design. The FTQH receiver achieves wideband sub-1dB NF and supports scalable massive frequency-agile concurrent reception

BestConfig: Tapping the Performance Potential of Systems via Automatic Configuration Tuning

An ever increasing number of configuration parameters are provided to system users. But many users have used one configuration setting across different workloads, leaving untapped the performance potential of systems. A good configuration setting can greatly improve the performance of a deployed system under certain workloads. But with tens or hundreds of parameters, it becomes a highly costly task to decide which configuration setting leads to the best performance. While such task requires the strong expertise in both the system and the application, users commonly lack such expertise. To help users tap the performance potential of systems, we present BestConfig, a system for automatically finding a best configuration setting within a resource limit for a deployed system under a given application workload. BestConfig is designed with an extensible architecture to automate the configuration tuning for general systems. To tune system configurations within a resource limit, we propose the divide-and-diverge sampling method and the recursive bound-and-search algorithm. BestConfig can improve the throughput of Tomcat by 75%, that of Cassandra by 63%, that of MySQL by 430%, and reduce the running time of Hive join job by about 50% and that of Spark join job by about 80%, solely by configuration adjustment

EmotionPrompt: Leveraging Psychology for Large Language Models Enhancement via Emotional Stimulus

Large language models (LLMs) have achieved significant performance in many fields such as reasoning, language understanding, and math problem-solving, and are regarded as a crucial step to artificial general intelligence (AGI). However, the sensitivity of LLMs to prompts remains a major bottleneck for their daily adoption. In this paper, we take inspiration from psychology and propose EmotionPrompt to explore emotional intelligence to enhance the performance of LLMs. EmotionPrompt operates on a remarkably straightforward principle: the incorporation of emotional stimulus into prompts. Experimental results demonstrate that our EmotionPrompt, using the same single prompt templates, significantly outperforms original zero-shot prompt and Zero-shot-CoT on 8 tasks with diverse models: ChatGPT, Vicuna-13b, Bloom, and T5. Further, EmotionPrompt was observed to improve both truthfulness and informativeness. We believe that EmotionPrompt heralds a novel avenue for exploring interdisciplinary knowledge for humans-LLMs interaction.Comment: Work in progress; 9 page

Elucidation of the mechanisms and molecular targets of Yiqi Shexue formula for treatment of primary immune thrombocytopenia based on network pharmacology

Yiqi Shexue formula (YQSX) is traditionally used to treat primary immune thrombocytopenia (ITP) in clinical practice of traditional Chinese medicine. However, its mechanisms of action and molecular targets for treatment of ITP are not clear. The active compounds of YQSX were collected and their targets were identified. ITP-related targets were obtained by analyzing the differential expressed genes between ITP patients and healthy individuals. Protein-protein interaction (PPI) data were then obtained and PPI networks of YQSX putative targets and ITP-related targets were visualized and merged to identify the candidate targets for YQSX against ITP. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis were carried out. The gene-pathway network was constructed to screen the key target genes. In total, 177 active compounds and 251 targets of YQSX were identified. Two hundred and thirty differential expressed genes with an P value 1 were identified between ITP patient and control groups. One hundred and eighty-three target genes associated with ITP were finally identified. The functional annotations of target genes were found to be related to transcription, cytosol, protein binding, and so on. Twenty-four pathways including cell cycle, estrogen signaling pathway, and MAPK signaling pathway were significantly enriched. MDM2 was the core gene and other several genes including TP53, MAPK1, CDKN1A, MYC, and DDX5 were the key gens in the gene-pathway network of YQSX for treatment of ITP. The results indicated that YQSX's effects against ITP may relate to regulation of immunological function through the specific biological processes and the related pathways. This study demonstrates the application of network pharmacology in evaluating mechanisms of action and molecular targets of complex herbal formulations

Effect of transcutaneous auricular vagus nerve stimulation on impaired glucose tolerance: a pilot randomized study

Background: Impaired glucose tolerance (IGT) is a pre-diabetic state of hyperglycemia that is associated with insulin resistance, increased risk of type II diabetes, and cardiovascular pathology. Recently, investigators hypothesized that decreased vagus nerve activity may be the underlying mechanism of metabolic syndrome including obesity, elevated glucose levels, and high blood pressure. Methods: In this pilot randomized clinical trial, we compared the efficacy of transcutaneous auricular vagus nerve stimulation (taVNS) and sham taVNS on patients with IGT. 72 participants with IGT were single-blinded and were randomly allocated by computer-generated envelope to either taVNS or sham taVNS treatment groups. In addition, 30 IGT adults were recruited as a control population and not assigned treatment so as to monitor the natural fluctuation of glucose tolerance in IGT patients. All treatments were self-administered by the patients at home after training at the hospital. Patients were instructed to fill in a patient diary booklet each day to describe any side effects after each treatment. The treatment period was 12 weeks in duration. Baseline comparison between treatment and control group showed no difference in weight, BMI, or measures of systolic blood pressure, diastolic blood pressure, fasting plasma glucose (FPG), 2-hour plasma glucose (2hPG), or glycosylated hemoglobin (HbAlc). Results: 100 participants completed the study and were included in data analysis. Two female patients (one in the taVNS group, one in the sham taVNS group) dropped out of the study due to stimulation-evoked dizziness. The symptoms were relieved after stopping treatment. Compared with sham taVNS, taVNS significantly reduced the two-hour glucose tolerance (F(2) = 5.79, p = 0.004). In addition, we found that taVNS significantly decreased (F(1) = 4.21, p = 0.044) systolic blood pressure over time compared with sham taVNS. Compared with the no-treatment control group, patients receiving taVNS significantly differed in measures of FPG (F(2) = 10.62, p < 0.001), 2hPG F(2) = 25.18, p < 0.001) and HbAlc (F(1) = 12.79, p = 0.001) over the course of the 12 week treatment period. Conclusions: Our study suggests that taVNS is a promising, simple, and cost-effective treatment for IGT/ pre-diabetes with only slight risk of mild side-effects

Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field

Cavity flows and wake behind an elliptic cylinder translating above the wall

Vortex formation is one of the fundamental modes in fluid mechanics and it can develop in almost every realization of fluid motion. Studying its fundamental dynamics and interactions is of great interest for engineering applications; the vortex shedding behind slender cylindrical structures with various cross sections like pipelines, risers, bridges, buildings and wind turbine blades, can cause fluctuating drag and lift forces, which lead to the vortex-induced vibration (VIV), causing the material subjected to periodic bending stresses, which eventually can lead to fracture; the vortex shedding behind the offshore pipeline placed on/close to the seabed determines the gentle slope of the downstream scour hole. In order to understand the complex physics underpinning the vortex dynamics, some classical flow problems, i.e. oscillatory lid-driven cavity flows, cavity flows with an inserted cylinder and wake behind an elliptic cylinder translating above a wall, which are dominated by the vortex flow have been investigated numerically in the present thesis. Flow in a two-dimensional oscillatory lid-driven rectangular cavity with a depth-to-width ratio 1:2 is investigated, covering a wide range of Reynolds numbers (based on the velocity amplitude and the cavity depth) and Stokes numbers (based on the lid oscillation angular frequency and the cavity depth) where this flow is known to be in the two-dimensional regime. Effects of these two parameters on vortex dynamics, vertical and horizontal centerline velocities and the drag force on the lid are presented and discussed. Four different flow patterns are classified based on the vortex dynamics. Moreover, the corner singularity effect on the flow patterns is also presented and discussed. Effects of an inserted circular cylinder on a steady lid-driven cavity flow are investigated and discussed for different Reynolds numbers (based on the lid motion velocity and the cavity depth), depth-to-width ratios, cylinder radii and locations. An immersed boundary method is applied to treat the circular cylinder surface. Numerical results concerning the vortex structures and pressure distribution around the cylinder are presented and discussed. For the depth-to-width ratio of 1:2, seven flow patterns have been classified based on the vortex structures and their distributions are presented as a function of the Reynolds numbers and the cylinder radii for a given cylinder location. Wake behind an elliptic cylinder translating above a plane wall is investigated numerically for Reynolds numbers less than 150 and gap ratios from 0.1 to 5 (i.e., the ratio between the gap and semi-major axis length of the elliptic cylinder). Numerical results concerning the steady and unsteady wake structures Karman vortex street, the two-layered wake and the secondary vortex street), the hydrodynamic forces and the onset location of the two-layered wake are presented and discussed. Four flow patterns are classified based on the wake structure and their distributions are given in the space of the Reynolds number and the gap ratio. Numerical simulations of the oscillating boundary layer on a plane wall have been conducted for = 500 and 1120 (based on the boundary layer thickness and the amplitude of the oscillation velocity), and the present results for the wall shear stress and instantaneous vorticity contours are in a good agreement with previous numerical and experimental results