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Preclinical and clinical studies have suggested a neuroprotective effect of remote ischemic conditioning (RIC), which involves repeated occlusion/release cycles on bilateral upper limb arteries; however, robust evidence in patients with ischemic stroke is lacking.To assess the efficacy of RIC for acute moderate ischemic stroke.This multicenter, open-label, blinded-end point, randomized clinical trial including 1893 patients with acute moderate ischemic stroke was conducted at 55 hospitals in China from December 26, 2018, through January 19, 2021, and the date of final follow-up was April 19, 2021.Eligible patients were randomly assigned within 48 hours after symptom onset to receive treatment with RIC (using a pneumatic electronic device and consisting of 5 cycles of cuff inflation for 5 minutes and deflation for 5 minutes to the bilateral upper limbs to 200 mm Hg) for 10 to 14 days as an adjunct to guideline-based treatment (n = 922) or guideline-based treatment alone (n = 971).The primary end point was excellent functional outcome at 90 days, defined as a modified Rankin Scale score of 0 to 1. All end points had blinded assessment and were analyzed on a full analysis set.Among 1893 eligible patients with acute moderate ischemic stroke who were randomized (mean [SD] age, 65 [10.3] years; 606 women [34.1%]), 1776 (93.8%) completed the trial. The number with excellent functional outcome at 90 days was 582 (67.4%) in the RIC group and 566 (62.0%) in the control group (risk difference, 5.4% [95% CI, 1.0%-9.9%]; odds ratio, 1.27 [95% CI, 1.05-1.54]; P = .02). The proportion of patients with any adverse events was 6.8% (59/863) in the RIC group and 5.6% (51/913) in the control group.Among adults with acute moderate ischemic stroke, treatment with remote ischemic conditioning compared with usual care significantly increased the likelihood of excellent neurologic function at 90 days. However, these findings require replication in another trial before concluding efficacy for this intervention.ClinicalTrials.gov Identifier: NCT03740971.

Treatment of grating stimulation has been used in amblyopia for decades, but high dropout rate and inconvenience for daily practice occur in previous studies. We developed a home-based portable system with rotating grating stimulation on a tablet. Thirty anisometropic amblyopic children were randomly allocated into the control or Grating group. They drew contour of the picture under patch of a better eye for 6 months. Best-corrected visual acuity (BCVA), grating acuity (GA), and contrast sensitivity (CS) were assessed at the baseline, 1st, 2nd, 3rd, and 6th months of training. All participants completed the 6-month training. Patched eyes of both groups exhibited no difference. Trained eyes of the control group had significantly slight improvement in BCVA and GA. In particular, the Grating group exhibited significantly higher BCVA, GA, and CS compared with those of the control group at the 3rd and 6th months of training. Moreover, percentage of the Grating group with great improvement (BCVA ≥ 0.3 or CS ≥ 0.3) was significantly larger than those of the control group at the 3rd or 6th months of training. The portable grating stimulation system demonstrates its trainability by no dropout and effectiveness by significant improvements in all assessments through a well experimental design.Trial Registration: ClinicalTrials.gov NCT04213066, registered 30/12/2019, https://clinicaltrials.gov/ct2/show/NCT04213066.

With the widespread use of cloud computing and the Internet, applications that require a large memory footprint, such as in-memory databases, have gained in popularity. These applications depend on a high capacity, reliable memory architecture. To achieve these two goals, hybrid memory that uses both DRAM and nonvolatile memory (NVM) provides benefits that include large capacity and nonvolatility. However, NVM is usually accompanied by high write latency and endurance problems. It is important to reduce NVM writes and improve the latency and lifetime of hybrid memory. One way to reduce NVM writes is to reduce dead pages that occupy DRAM and have not been accessed for a long time. When dead pages are removed from the memory, more space can be reserved for frequently accessed data, reducing DRAM misses and NVM writes. Currently, there are several dead block prediction techniques that can identify dead blocks and reduce miss rates at the cache level. However, they are not effective at the memory level because CPU memory accesses exhibit less locality when accesses are filtered by caches. To propose an application that is suitable at the memory level and to achieve a reduction in NVM writes, this paper proposes a simple but effective dead page predictor, called the infection-based dead page predictor (IDP), for the memory level. IDP uses the access counts of evicted pages to determine if nearby pages are also dead pages (i.e., other pages are infected by evicted pages). The simulation results show that compared to related work, the proposed predictor significantly reduces DRAM misses and enhances lifetime.

Scratchpad memory (SPM), a software-controlled on-chip memory, is being increasingly used in embedded systems to reduce on-chip memory energy consumption. To further reduce energy consumption, multibank SPM architecture is proposed. In multibank SPM, each bank can be accessed independently, and unused banks can enter the low power mode, thus reducing leakage energy. However, if both frequently and infrequently used data exist in the same bank, the bank will not be able to enter the low power mode, resulting in less energy reduction. To address this issue, we propose online page clustering for multibank SPM (OCMAS) to reduce the leakage energy in multibank SPM. OCMAS groups SPM pages with similar access frequencies into the same bank, allowing banks containing infrequently used data to stay in low power mode longer. We also propose a method to dynamically adjust the thresholds for determining cold pages (pages that contain infrequently used data), so banks that contain cold pages can enter the low power mode with a shorter idle timeout. Compared to conventional timeout-based, periodic drowsy, and bank-based methods, OCMAS can reduce the energy delay product by up to 37.67% (18.14% on average), 39.53% (22.38% on average), and 132.32% (23.34% on average) in 32 KB 4-bank SPM, by up to 25.33% (15.71% on average), 29.87% (15.92% on average), and 72.25% (22.64% on average) in 32 KB 8-bank SPM, by up to 28.99% (13.45% on average), 30.71% (14.74% on average), and 96.67% (19.94% on average) in 16 KB 4-bank SPM, and by up to 30.18% (10.05% on average), 32.13% (11.62% on average), and 65.56% (16.2% on average) in 16 KB 8-bank SPM. The area overhead is approximately 0.72%, which is insignificant.

BACKGROUND Rheumatic mitral valve repair and replacement techniques are frequently used with excellent outcomes in experienced centers. This study aims to evaluate the impact of procedural types on left ventricular function in quinquagenarians. METHODS Between January 2018 and September 2019, patients with severe rheumatic mitral stenosis were prospectively recruited. Propensity score matching was performed to reduce the selection bias. We compared the strain, twist and synchrony parameters of left ventricle in 70 quinquagenarian patients who underwent rheumatic mitral valve repair and replacement 12 hours before surgery, at 7 days and 6 months postoperatively. RESULTS The overall group displayed significant improvement of left ventricular deformation after rheumatic mitral valve surgery. Compared with patients undergoing posterior chordal-sparing mitral valve replacement, patients undergoing rheumatic mitral valve repair showed more significant amelioration in global longitudinal strain (-18.6% versus -16.2%, P

Objective: In this study, a wearable actigraphy recording device with low sampling rate (1 Hz) for power saving and data reduction and a high accuracy wake-sleep scoring method for the assessment of sleep were developed. Methods: The developed actigraphy recorder was successfully applied to overnight recordings of 81 subjects with simultaneous polysomnography (PSG) measurements. The total length of recording reached 639.8 h. A wake-sleep scoring method based on the concept of movement density evaluation and adaptive windowing was proposed. Data from subjects with good ( N = 43) and poor ( N = 16) sleep efficiency (SE) in the range of 52.7–97.42% were used for testing. The Bland–Altman technique was used to evaluate the concordance of various sleep measurements between the manual PSG scoring and the proposed actigraphy method. Results: For wake-sleep staging, the average accuracy, sensitivity, specificity, and kappa coefficient of the proposed system were 92.16%, 95.02%, 71.30%, and 0.64, respectively. For the assessment of SE, the accuracy of classifying the subject with good or poor SE reached 91.53%. The mean biases of SE, sleep onset time, wake after sleep onset, and total sleep time were −0.95%, 0.74 min, 2.84 min, and −4.3 min, respectively. Conclusion: These experimental results demonstrate the robustness and reliability of our method using limited activity information to estimate wake-sleep stages during overnight recordings. Significance: The results suggest that the proposed wearable actigraphy system is practical for the in-home screening of objective sleep measurements and objective evaluation of sleep improvement after treatment.

In recent decades, cloud-based shared storage services create a promising solution for data store. In a shared storage, performance isolation and fairness is critical. To boost input-output performance, operating systems employ a kernel managed caching space called the buffer cache or page cache. In a shared storage, owing to the different access characteristics of tenants' workloads, the page cache would be allocated unevenly, leading to unfair performance distribution mto tenants. Therefore, we propose a framework for performance isolation and fairness in a shared storage system. First, the framework explores how to dynamically allocate page cache space among tenants for performance fairness. Then, the framework utilizes credit-based I/O scheduler for performance fairness in storage devices. The experimental results show that, with the proposed framework, interference in a shared storage system can be eliminated and performance fairness can be ensured.

NAND flash memory-based solid-state drives (SSDs) have been increasingly used in storage systems. Compared to single-level cell (SLC) NAND, which stores 1 bit per cell, multi-level cell (MLC) NAND stores 2 or more bits per cell, enabling higher-capacity and lower-cost SSDs. However, MLC NAND has inferior write performance compared to SLC NAND. A method to improve the write performance is to exploit the performance variability in MLC flash memory by skipping the slow pages (i.e., data writes always served by fast pages). However, excessive page skips cause the free space of the SSD to be consumed quickly, harmful to the SSD performance and lifetime. In this paper, a selective page skip mothed called SSKIP is proposed to improve the MLC write performance while maintaining the target SSD lifetime. According to the performance results, SSKIP can improve the performance by up to 56% by performing page skips. Moreover, it prevents violating the target lifetime warranty due to excessive page skips.

Although digoxin is important in heart rate control, the utilization of digoxin is declining due to its narrow therapeutic window. Misdiagnosis or delayed diagnosis of digoxin toxicity is common due to the lack of awareness and the time-consuming laboratory work that is involved. Electrocardiography (ECG) may be able to detect potential digoxin toxicity based on characteristic presentations. Our study attempted to develop a deep learning model to detect digoxin toxicity based on ECG manifestations. This study included 61 ECGs from patients with digoxin toxicity and 177,066 ECGs from patients in the emergency room from November 2011 to February 2019. The deep learning algorithm was trained using approximately 80% of ECGs. The other 20% of ECGs were used to validate the performance of the Artificial Intelligence (AI) system and to conduct a human-machine competition. Area under the receiver operating characteristic curve (AUC), sensitivity, and specificity were used to evaluate the performance of ECG interpretation between humans and our deep learning system. The AUCs of our deep learning system for identifying digoxin toxicity were 0.912 and 0.929 in the validation cohort and the human-machine competition, respectively, which reached 84.6% of sensitivity and 94.6% of specificity. Interestingly, the deep learning system using only lead I (AUC = 0.960) was not worse than using complete 12 leads (0.912). Stratified analysis showed that our deep learning system was more applicable to patients with heart failure (HF) and without atrial fibrillation (AF) than those without HF and with AF. Our ECG-based deep learning system provides a high-accuracy, economical, rapid, and accessible way to detect digoxin toxicity, which can be applied as a promising decision supportive system for diagnosing digoxin toxicity in clinical practice.

The NAND flash memory has been widely used in computer and consumer electronic devices. A multilevel-cell (MLC) NAND flash memory allows two or more bits to be stored per cell, improving the cell density and, hence, reducing the cost. The lower price of the MLC NAND has made it appearing in both consumer product and datacenter markets. In MLC NAND, the page read latency varies according to the page type. For read-dominated workloads, placing read-intensive data into pages with longer read latencies may result in degraded read performance. In this brief, an online method called FastRead is proposed to improve the read performance of MLC NAND-based storage. The FastRead method dynamically identifies read-intensive data and migrates them to pages with shorter read latency to improve the read performance. According to the performance results, FastRead can reduce the read response time by up to 22% (17% on average) for read-dominated workloads on a Triple-level cell NAND. In addition, FastRead does not have noticeable performance impact for write-dominated workloads, and the overhead is insignificant.

In a multi-tiered storage system, both page cache and solid-state drives are used as the cache of hard disk drives. However, in the current I/O architecture, page cache and SSD cache are managed independently. Thus, page cache and SSD cache managers make the caching and replacement decisions independently. As a result, system performance is limited due to factors including metadata duplication and improper management of the page cache and SSD cache spaces. To address the limitations of the current I/O architecture, we propose a new I/O architecture to enable the information sharing between the page cache and SSD cache managers. By our proposed architecture, the page cache and SSD cache managers can cooperate with each other so that the overall I/O performance is maximized.

Robotics, as an innovation of minimally invasive surgical methods, is developing rapidly for colectomy. But there is still no consensus on its comparative merit compared with laparoscopic resections. We conducted this meta-analysis that included randomized controlled trials and nonrandomized controlled trials of robotic colectomy (RC) versus laparoscopic colectomy (LC) to evaluate whether the safety and efficacy of RC are equivalent to those of LC.A search of five databases (PubMed, Embase, Cochrane Library, Ovid, and Web of Science), gray literature, hand searches, reference, and forward citation were performed for studies that compared clinical or oncologic outcomes of LC with RC. Clinical outcomes evaluated were conversion rates, operation times, estimated blood loss, length of hospital stay, and complications. Oncologic outcome evaluated was the number of lymph nodes collected.A total of 14 studies were identified that included 125,989 patients in total, 4934 in the robotic cohort and 121,055 in the laparoscopic cohort. Meta-analysis suggested that there was a significantly longer hospital stay in the laparoscopic group (mean difference [MD] -0.65; 95% confidence interval [CI] -1.02 to -0.27; P = 0.0008). Robotic surgery was associated with a significantly lower complication rate (odds ratio 0.78; 95% CI 0.72-0.85; P ＜ 0.00001) and a significantly shorter time to recovery of bowel function (MD -0.58; 95% CI -0.96 to -0.20; P = 0.003). There were statistically significant differences in estimated blood loss (MD -19.24; 95% CI -29.38 to -9.09; P = 0.0002) and intraoperative conversion to open (odds ratio 0.56; 95% CI 0.44-0.72; P0.00001), but not clinical relevant. There were no significant differences in the number of lymph nodes extracted between the two groups. However, operating time (MD 49.25; 95% CI 36.78-61.72; P0.00001) was longer for RC than for LC.RC can be performed safely and effectively with the number of lymph nodes extracted similar to LC. In addition, it can provide potential advantages of a shorter hospital stay, a shorter time to recovery of bowel function, and lower occurrence of postoperative complications. These findings seem to support the use of robotics for the minimally invasive surgical management of colectomy. However, RC had longer operating time. Future studies involving RC should focus on minimizing duration of operation.

Scratchpad memory (SPM) has been increasingly used in embedded systems due to its higher efficiency in terms of energy and area compared to that of ordinary cache. A hybrid on-chip memory architecture that combines SPM with a mini-cache has been proposed. One key issue for hybrid on-chip memory architectures is to reduce the number of off-chip memory accesses and energy consumption. Existing methods achieve this by moving the most frequently accessed data into SPM. However, these methods may be ineffective because the main source of off-chip memory accesses may not be the most frequently accessed data. Instead, most off-chip memory accesses are caused by cache misses, so reducing the latter will reduce the former. Cache misses are mainly caused by data contending for cache lines. Therefore, this paper proposes a contention-aware SPM allocation method for hybrid on-chip management. The number of cache misses for a page is used as a metric to determine whether a page should be moved to SPM. When the number of misses for a page exceeds a threshold, the page is moved to SPM, reducing cache contention. Experimental results show that the proposed method can reduce the energy delay product by 35% to 53% compared to a cache-only on-chip memory architecture and 19% to 31% compared to an existing hybrid on-chip memory architecture.

A hybrid file system with high flexibility and performance, called Trident file system TridentFS, is proposed to manage three types of storage with different performance characteristics, that is, Non-Volatile RAM NVRAM, flash memory and magnetic disk. Unlike previous NVRAM-based hybrid file systems, novel techniques are used in TridentFS to improve the flexibility and performance. TridentFS is flexible by the support of various forms of flash memory and a wide range of NVRAM size. The former is achieved on the basis of the concept of stackable file systems, and the latter is achieved by allowing data eviction from the NVRAM. TridentFS achieves high performance by keeping hot data in the NVRAM and allowing data evicted from the NVRAM to be parallel distributed to the flash memory and disk. A data eviction policy is proposed to determine the data to be evicted from the NVRAM. Moreover, a data distribution algorithm is proposed to effectively leverage the parallelism between flash memory and disk during data distribution. TridentFS is implemented as a loadable module on Linux 2.6.29. The performance results show that it works well for both small-sized and large-sized NVRAM, and the proposed eviction policy outperforms LRU by 27%. Moreover, by effectively leveraging the parallelism between flash memory and disk, the proposed data distribution algorithm outperforms the RAID-0 and a size-based distribution method by up to 471.6% and 82.6%, respectively. By considering the data size and performance characteristics of the storage, the proposed data distribution algorithm outperforms the greedy algorithm by up to 15.5%. Copyright © 2014 John Wiley & Sons, Ltd.

Recently, Li et al. (Int. J. Theor. Phys. 46, 2599, 2007) has constructed the quantum superimposing multiple anti-cloning machine, moreover established the sufficient and necessary condition of this machine exists. In the proofs given by Li et al. (Int. J. Theor. Phys. 46, 2599, 2007), claimed that the following key fact to hold : Fact For an arbitrary unknown state |ψ〉 belongs to n-dimensional Hilbert space, there exists an antiunitary operator K such that K|ψ〉=|ψ⊥〉 here the state |ψ⊥〉 is an orthogonal complement state of |ψ〉, that is, it satisfies the following two conditions 〈ψ|K|ψ〉=〈ψ|ψ⊥〉=0 and 〈ψ|ψ〉=〈ψ⊥|ψ⊥〉=1 In this Comment, we would like to point out that (a). In 1-dimensional Hilbert space, for an arbitrary unknown state |ψ〉, the antiunitary operator K and the orthogonal complement state both do not exist in general. (b). In 3-dimensional Hilbert space, for an arbitrary unknown state |ψ〉, the antiunitary operator K do not exist in general, there are uncountably many orthogonal complement states that can be constructed through the skew-symmetric operator, but is not unitary one. Which shows that above Fact given by Li et al. [1] is incorrect in general for both 1 and 3-dimensional Hilbert space

Recently, a hybrid disk drive that integrates a small amount of flash memory within a mechanical drive has received significant attention. The hybrid drive extends the storage hierarchy by using flash memory to cache data from the mechanical disk. Unfortunately, current caching architectures fail to fully exploit the potential of the hybrid drive. Furthermore, current disk input/output I/O schedulers are optimized for rotational mechanical disk drives and thus must be re-targeted for the hybrid disk drive. In this paper, we propose a new data caching scheme, called Profit Caching, for hybrid drives. Profit Caching is a self-optimizing caching algorithm. It considers and seamlessly integrates all possible data characteristics that impact the performance of hybrid drives, including read count, write count, sequentiality, randomness, and recency, to determine the caching policy. Moreover, we propose a hybrid disk-aware Completely Fair Queuing HA-CFQ scheduler to avoid unnecessary I/O anticipations of the CFQ scheduler. We have implemented Profit Caching and HA-CFQ scheduler in the Linux kernel. Coupled with a trace-driven simulator, we have also conducted detailed experiments under a variety of workloads. Experimental results show that Profit Caching provides significantly improved performance compared with the previous schemes. In particular, the throughput of Profit Caching outperforms previous Random Access First and FlashCache caching schemes by factors of up to 1.8 and 7.6, respectively. In addition, the HA-CFQ scheduler reduces the total execution time of the CFQ scheduler by up to 1.74%. Finally, the experimental results show that the runtime overhead of Profit Caching is extremely insignificant and can be ignored. Copyright © 2014 John Wiley & Sons, Ltd.

Increasing the degree of parallelism and reducing the overhead of garbage collection (GC overhead) are the two keys to enhancing the performance of solid-state drives (SSDs). SSDs employ multichannel architectures, and a data placement scheme in an SSD determines how the data are striped to the channels. Without considering the data access pattern, existing fixed and device-level data placement schemes may have either high GC overhead or poor I/O parallelism, resulting in degraded performance. In this article, an adaptive block-level data placement scheme called BLAS is proposed to maximize the I/O parallelism while simultaneously minimizing the GC overhead. In contrast to existing device-level schemes, BLAS allows different data placement policies for blocks with different access patterns. Pages in read-intensive blocks are scattered over various channels to maximize the degree of read parallelism, while pages in each of the remaining blocks are attempted to be gathered in the same physical block to minimize the GC overhead. Moreover, BLAS allows the placement policy for a logical block to be changed dynamically according to the access pattern changes of that block. Finally, a parallelism-aware write buffer management approach is adopted in BLAS to maximize the degree of write parallelism. Performance results show that BLAS yields a significant improvement in the SSD response time when compared to existing device-level schemes. In particular, BLAS outperforms device-level page striping and device-level block striping by factors of up to 8.75 and 7.41, respectively. Moreover, BLAS achieves low GC overhead and is effective in adapting to workload changes.

Recently, the multi-tiered storage systems that are composed of hard disk drives (HDDs) and solid state disk drives (SSDs) have received significant attention. The multi-tiered storage system extends the storage hierarchy by using SSDs to cache data from the HDDs. Thus, how to cache the appropriate data on the SSDs becomes an important issue for the multi-tiered storage systems. Due to the tremendous superior access performance of SSDs, current data caching schemes tried to cache the hottest data in SSDs, expecting that all of the disk I/O requests can be served by the SSDs. However, when the disk I/O load is heavy, such a scheme would saturate the bandwidths of SSDs and cause a negative impact on the I/O performance. To address this issue, on the basis of Profit Caching, this paper proposes a new data caching scheme, called Load-Balancing Caching Scheme (LBSC), for multi-tiered storage systems. LBSC takes the instant load of different storage devices for making the caching decision. Specifically, LBSC balance the load of SSDs and HDDs so as to fully exploit both the potential bandwidths of the SSDs and HDDs. We have implemented our scheme in a DiskSim-based multi-tiered storage simulator. From the experimental results, our proposed LBSC data caching scheme can significantly enhance the I/O performance of Profit Caching.

Recently, Li et al. (Int. J. Theor. Phys. 53(9), 2923–2930 (2014)) presented the concrete representation of density matrix of symmetric quantum states . Moreover , according to this concrete representation of the density matrix for symmetric quantum states, Li et al. (Int. J. Theor. Phys. 53(9), 2923–2930 (2014)) have established Theorem 4.1. In this Comment, we would like to point out that Theorem 4.1 given by Li et al. (Int. J. Theor. Phys. 53(9), 2923–2930 (2014)) is incorrect in general.

Recently, Tao et al. (Int. J. Theor. Phys. 52 (6), 1970–1978, 2013) established a representation of density matrix for multipartite quantum system. Moreover, according to this representation of the density matrix for multipartite quantum system, Tao et al. (Int. J. Theor. Phys. 52 (6), 1970–1978, 2013) have presented two necessary criteria for separability of multipartite quantum system of arbitrary dimensions, for example, see Theorem 2.1 and Theorem 2.2. In this Comment, we would like to point out that Theorem 2.2 given by Tao et al. (Int. J. Theor. Phys. 52 (6), 1970–1978, 2013) is incorrect in general.

Vitamin E (VE) was encapsulated in glassy carbohydrates by extrusion. Four typical formulations were prepared in order to have 5% and 8% VE added to each 20% and 30% modified starch containing feed material, all four formulations contained soya lecithin at 1% level as an emulsifier. The physico-chemical properties of glassy extruded products were investigated. The results showed that the VE retention rates were above 93%, meanwhile the VE oil was dispersed uniformly throughout the carbohydrate mass after extrusion. There was a slight loss for VE during the storage. The glass transition temperature (Tg) of the extrudates were above 30°C and Tg could be a good predictor of caking properties at elevated temperatures.

Home Network-Attached Storage (NAS) provides an easy way for data sharing and backup among multiple consumer electronic devices in home networks. Because of large capacity and cost effectiveness, disks are widely adopted in home NAS devices. In addition, data writes are common for many home NAS devices since these devices are usually used for data storage and backup. A writeback policy selects which dirty buffers are to be flushed to the disk, which is critical to the system performance under write-intensive workloads. In this paper, an intelligent writeback policy for home NAS called TESA is proposed. In contrast to most existing writeback policies, TESA considers both temporal and spatial information of the dirty buffers to improve the writeback performance. Considering the temporal information helps to reduce the frequency of writing back recently used dirty buffers, and hence leads to reduced write traffic. Considering the spatial information causes a reduction in the overall seek time and rotation delay of the dirty buffer writeback. The TESA writeback policy was implemented on a NAS evaluation board running Linux kernel. The performance results shows that TESA yields a significant performance improvement (i.e., up to 33.1%) over the original writeback policy of Linux. Moreover, TESA outperforms the policy that considers only the temporal information of the dirty buffers by up to 21.0%, and it also has up to 10.9% performance improvement over a previous policy that considers both the temporal and spatial information.

Background This study assessed the short-, medium-, and long-term outcomes of coronary artery bypass grafting vs stenting for patients with unprotected left main coronary artery disease through a meta-analysis of randomized controlled trials. Methods PubMed, Embase, Scopus, Web of Science, Cochrane Library, and major conference proceedings databases were systematically searched for randomized controlled trials of coronary artery bypass grafting compared with stents in unprotected left main coronary artery disease. End points assessed were all-cause death, myocardial infarction, major adverse cardiac and cerebrovascular events, target vessel revascularization, and cerebral stroke. A meta-analysis was conducted according to predefined clinical end points. Results All-cause death and stroke were similar between stenting and coronary artery bypass grafting at 1 year and at follow-up beyond 1 year. The incidence of myocardial infarction was similar between stenting and coronary artery bypass grafting at each separate time point. The incidence of repeat revascularization was similar between the two groups at 30 days but was higher for stenting at 1 year and beyond. There was a trend toward fewer major adverse cardiac and cerebrovascular events after stenting compared with coronary artery bypass grafting at 30 days, but this difference was no longer significant at 1 year and reversed at follow-up beyond 1 year. Conclusions The early advantages of stenting over coronary artery bypass grafting have been shown to progressively shift to coronary artery bypass grafting over time. Further larger sample randomized controlled trials are warranted to confirm the results.