This paper studies distributed algorithms for (strongly convex) composite optimization problems over mesh networks, subject to quantized communications. Instead of focusing on a specific algorithmic ...design, a black-box model is proposed, casting linearly convergent distributed algorithms in the form of fixed-point iterates. The algorithmic model is equipped with a novel random or deterministic Biased Compression (BC) rule on the quantizer design, and a new Adaptive encoding Non-uniform Quantizer (ANQ) coupled with a communication-efficient encoding scheme, which implements the BC-rule using a finite number of bits (below machine precision). This fills a gap existing in most state-of-the-art quantization schemes, such as those based on the popular compression rule, which rely on communication of some scalar signals with negligible quantization error (in practice quantized at the machine precision). A unified communication complexity analysis is developed for the black-box model, determining the average number of bits required to reach a solution of the optimization problem within a target accuracy. It is shown that the proposed BC-rule preserves linear convergence of the unquantized algorithms, and a trade-off between convergence rate and communication cost under ANQ-based quantization is characterized. Numerical results validate our theoretical findings and show that distributed algorithms equipped with the proposed ANQ have more favorable communication cost than algorithms using state-of-the-art quantization rules.
This article proposes the first distributed algorithm that solves the weight-balancing problem using only finite rate and simplex communications among nodes, compliant with the directed nature of the ...graph edges. It is proved that the algorithm converges to a weight-balanced solution at sublinear rate. The analysis builds upon a new metric inspired by positional system representations, which characterizes the dynamics of information exchange over the network, and on a novel step-size rule. Building on this result, a novel distributed algorithm is proposed that solves the average consensus problem over digraphs, using, at each timeslot, finite rate simplex communications between adjacent nodes-some bits for the weight-balancing problem and others for the average consensus. Convergence of the proposed quantized consensus algorithm to the average of the node's unquantized initial values is established, both almost surely and in the moment generating function of the error; and a sublinear convergence rate is proved for sufficiently large step-sizes. Numerical results validate our theoretical findings.
This study investigated the effect of melatonin on clinical outcomes in patients with coronavirus disease 2019 (COVID‐19). We searched PubMed, the Web of Science, the Cochrane Library, Ovid MEDLINE, ...and Clinicaltrials.gov for randomized controlled trials (RCTs) published before September 11, 2021. Only RCTs that compared the clinical efficacy of melatonin with a placebo in the treatment of patients with COVID‐19 were included. The primary outcome measure was the clinical recovery rate. We included three RCTs in this meta‐analysis. Melatonin 3 mg three times daily was administered in one RCT, and 3 or 6 mg daily before bedtime in the other two trials. Treatment duration was 14 days in two RCTs and 7 days in one trial. The clinical recovery rates were 94.2% (81/86) and 82.4% (70/85) in the melatonin and control groups, respectively. Overall, patients receiving melatonin had a higher clinical recovery rate than did the controls (odds ratio OR: 3.67; 95% CI: 1.21−11.12; I2 = 0%, p = 0.02). The risk of intensive care unit admission was numerically lower in the melatonin group than in the control group (8.3% 6/72 vs. 17.6% 12/68, OR: 0.45; 95% CI: 0.16−1.25; I2 = 0%, p = 0.13), and the risk of mortality was numerically lower in the melatonin group than in the control group (1.4% 1/72 vs. 4.4% 3/68, OR: 0.32; 95% CI: 0.03−3.18; I2 = 0%, p = 0.33). In conclusion, melatonin may help improve the clinical outcomes of patients with COVID‐19.
Highlight
This study investigated the effect of melatonin on clinical outcomes in patients with coronavirus disease 2019.
Patients receiving melatonin had a higher clinical recovery rate than did the controls (odds ratio: 3.67; 95% CI: 1.21−11.12; I2 = 0%, p = 0.02).
The risk of intensive care unit admission was only insignificantly lower in the melatonin group than in the control group.
The risk of mortality was insignificantly lower in the melatonin group than in the control group.
Deficiency in DNA damage response (DDR) genes leads to impaired DNA repair functions that will induce genomic instability and facilitate cancer development. However, alterations of DDR genes can ...serve as biomarkers for the selection of suitable patients to receive specific therapeutics, such as immune checkpoint blockade (ICB) therapy. In addition, certain altered DDR genes can be ideal therapeutic targets through adapting the mechanism of synthetic lethality. Recent studies indicate that targeting DDR can improve cancer immunotherapy by modulating the immune response mediated by cGAS-STING-interferon signaling. Investigations of the interplay of DDR-targeting and ICB therapies provide more effective treatment options for cancer patients. This review introduces the mechanisms of DDR and discusses their crucial roles in cancer therapy based on the concepts of synthetic lethality and ICB. The contemporary clinical trials of DDR-targeting and ICB therapies in breast, colorectal, and pancreatic cancers are included.
Massive multiple-input multiple-output (massive MIMO) has been studied to improve the throughput in cellular communication systems via spatial degrees of freedom and array gain. However, in massive ...MIMO systems, due to the hardware cost considerations, it is infeasible to install a radio frequency (RF) chain for each antenna. To deploy massive MIMO within reasonable hardware cost, hybrid precoding is proposed in which the signal is processed by a low-dimensional digital baseband precoder and a high-dimensional analog RF precoder. On the other hand, cooperative transmission is another way to enhance system throughput, in which base stations (BSs) can jointly transmit to a user. In this paper, we first investigate the hybrid precoder design for cooperative multiuser massive MIMO systems. We propose hybrid precoding algorithms for two performance metrics: weighted sum rate and max-min fairness. We also propose a low complexity user pairing for both precoder designs. Numerical results show that the proposed hybrid precoding algorithms outperform existing hybrid precoding algorithms for non-cooperative transmissions, and perform closely compared with existing digital precoding algorithms for cooperative transmissions, when the number of users does not exceed the total number of RF chains of the BSs in cooperative (i.e., the largest possible channel rank). In summary, this paper provides a hybrid precoder design guideline for existing and developing cellular communication systems, including Long Term Evolution-Advanced and the fifth generation cellular systems.
The generation of high-fidelity distributed multi-qubit entanglement is a challenging task for large-scale quantum communication and computational networks
. The deterministic entanglement of two ...remote qubits has recently been demonstrated with both photons
and phonons
. However, the deterministic generation and transmission of multi-qubit entanglement has not been demonstrated, primarily owing to limited state-transfer fidelities. Here we report a quantum network comprising two superconducting quantum nodes connected by a one-metre-long superconducting coaxial cable, where each node includes three interconnected qubits. By directly connecting the cable to one qubit in each node, we transfer quantum states between the nodes with a process fidelity of 0.911 ± 0.008. We also prepare a three-qubit Greenberger-Horne-Zeilinger (GHZ) state
in one node and deterministically transfer this state to the other node, with a transferred-state fidelity of 0.656 ± 0.014. We further use this system to deterministically generate a globally distributed two-node, six-qubit GHZ state with a state fidelity of 0.722 ± 0.021. The GHZ state fidelities are clearly above the threshold of 1/2 for genuine multipartite entanglement
, showing that this architecture can be used to coherently link together multiple superconducting quantum processors, providing a modular approach for building large-scale quantum computers
.
This paper presents a non-contact method for the detection of changes in sow vulva size in a group pen. The traditional approach to estrus detection is manually pressing down on the back of the sow ...to elicit standing responses; however, this method causes undue distress for sows not in estrus. When a sow is in estrus, the vulva is red and swollen due to the presence of endocrine. Monitoring changes in vulva size to detect estrus with as little impact on the sow as possible is the focus of this study. This is achieved using a single camera combined with a deep learning framework. Our approach comprises two steps: vulva detection and vulva size conversion. Images of sows of Yorkshire, Landrace, and Duroc breeds were collected in group housing, and the vulva was detected through artificial markers and the network architecture of YOLO v4. Based on the internal and external parameters of the camera, the detected size was converted into millimeters and the results of manual measurement (MM) and automatic calculation combined to calculate the size of the vulva. Analysis of the calculated size compared with MM indicates that the object recognition rate of the system exceeds 97.06%, with a size error of only + 1.70 to -4.47 mm and high-calculation efficiency (>2.8 frames/s). Directions for future research include the automatic detection of pig width.
To investigate the association between cannabis smoking and lung cancer risk, data on 2,159 lung cancer cases and 2,985 controls were pooled from 6 case‐control studies in the US, Canada, UK, and New ...Zealand within the International Lung Cancer Consortium. Study‐specific associations between cannabis smoking and lung cancer were estimated using unconditional logistic regression adjusting for sociodemographic factors, tobacco smoking status and pack‐years; odds‐ratio estimates were pooled using random effects models. Subgroup analyses were done for sex, histology and tobacco smoking status. The shapes of dose‐response associations were examined using restricted cubic spline regression. The overall pooled OR for habitual versus nonhabitual or never users was 0.96 (95% CI: 0.66–1.38). Compared to nonhabitual or never users, the summary OR was 0.88 (95%CI: 0.63–1.24) for individuals who smoked 1 or more joint‐equivalents of cannabis per day and 0.94 (95%CI: 0.67–1.32) for those consumed at least 10 joint‐years. For adenocarcinoma cases the ORs were 1.73 (95%CI: 0.75–4.00) and 1.74 (95%CI: 0.85–3.55), respectively. However, no association was found for the squamous cell carcinoma based on small numbers. Weak associations between cannabis smoking and lung cancer were observed in never tobacco smokers. Spline modeling indicated a weak positive monotonic association between cumulative cannabis use and lung cancer, but precision was low at high exposure levels. Results from our pooled analyses provide little evidence for an increased risk of lung cancer among habitual or long‐term cannabis smokers, although the possibility of potential adverse effect for heavy consumption cannot be excluded.
What's new?
Due to the potential adverse effect of cannabis smoking and its popularity, an investigation of its association with lung cancer risk is essential to help support appropriate regulations as well as health and social policy responses. The analysis presented here included the largest data set on cannabis and lung cancer risk to date. Its non‐linear dose‐response was examined using restricted cubic spline regression, a first in this line of work. Results provide little evidence for an increased risk of lung cancer among habitual or long‐term cannabis smokers, although the possibility of potential adverse effect for heavy consumption cannot be excluded.
Multistability is an extraordinary nonlinear property of dynamical systems and can be explored to implement memory and switches. Here we experimentally realize the tristability in a three-mode cavity ...magnonic system with Kerr nonlinearity. The three stable states in the tristable region correspond to the stable solutions of the frequency shift of the cavity magnon polariton under specific driving conditions. We find that the system staying in which stable state depends on the history experienced by the system, and this state can be harnessed to store the history information. In our experiment, the memory time can reach as long as 5.11 s. Moreover, we demonstrate the ternary logic gate with good on-off characteristics using this multistable hybrid system. Our new findings pave a way towards cavity magnonics-based information storage and processing.
Avian embryos are among the most convenient and the primary representatives for the study of classical embryology. It is well-known that the hatching time of duck embryos is approximately one week ...longer than that of chicken embryos. However, the key features associated with the slower embryonic development in ducks have not been adequately described. This study aimed to characterize the pattern and the speed of early embryogenesis in Brown Tsaiya Ducks (BTD) compared with those in Taiwan Country Chicken (TCC) by using growth parameters including embryonic crown-tail length (ECTL), primitive streak formation, somitogenesis, and other development-related parameters, during the first 72 h of incubation. Three hundred and sixty eggs from BTD and TCC, respectively, were incubated at 37.2°C, and were then dissected hourly to evaluate their developmental stages. We found that morphological changes of TCC embryos shared a major similarity with that of the Hamburger and Hamilton staging system during early chick embryogenesis. The initial primitive streak in TCC emerged between 6 and 7 h post-incubation, but its emergence was delayed until 10 to 13 h post-incubation in BTD. Similarly, the limb primordia (wing and limb buds) were observed at 51 h post-incubation in TCC embryos compared to 64 h post-incubation in BTD embryos. The allantois first appeared around 65 to 68 h in TCC embryos, but it was not observed in BTD embryos. At the 72 h post-incubation, 40 somites were clearly formed in TCC embryos while only 32 somites in BTD embryos. Overall, the BTD embryos developed approximately 16 h slower than the chicken embryo during the first 72 h of development. To our best knowledge, this is the first study to describe two distinct developmental time courses between TCC and BTD, which would facilitate future embryogenesis-related studies of the two important avian species in Taiwan.
PDF
