633 research outputs found

    Supervised Collective Classification for Crowdsourcing

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    Crowdsourcing utilizes the wisdom of crowds for collective classification via information (e.g., labels of an item) provided by labelers. Current crowdsourcing algorithms are mainly unsupervised methods that are unaware of the quality of crowdsourced data. In this paper, we propose a supervised collective classification algorithm that aims to identify reliable labelers from the training data (e.g., items with known labels). The reliability (i.e., weighting factor) of each labeler is determined via a saddle point algorithm. The results on several crowdsourced data show that supervised methods can achieve better classification accuracy than unsupervised methods, and our proposed method outperforms other algorithms.Comment: to appear in IEEE Global Communications Conference (GLOBECOM) Workshop on Networking and Collaboration Issues for the Internet of Everythin

    White-Box Transformers via Sparse Rate Reduction

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    In this paper, we contend that the objective of representation learning is to compress and transform the distribution of the data, say sets of tokens, towards a mixture of low-dimensional Gaussian distributions supported on incoherent subspaces. The quality of the final representation can be measured by a unified objective function called sparse rate reduction. From this perspective, popular deep networks such as transformers can be naturally viewed as realizing iterative schemes to optimize this objective incrementally. Particularly, we show that the standard transformer block can be derived from alternating optimization on complementary parts of this objective: the multi-head self-attention operator can be viewed as a gradient descent step to compress the token sets by minimizing their lossy coding rate, and the subsequent multi-layer perceptron can be viewed as attempting to sparsify the representation of the tokens. This leads to a family of white-box transformer-like deep network architectures which are mathematically fully interpretable. Despite their simplicity, experiments show that these networks indeed learn to optimize the designed objective: they compress and sparsify representations of large-scale real-world vision datasets such as ImageNet, and achieve performance very close to thoroughly engineered transformers such as ViT. Code is at \url{https://github.com/Ma-Lab-Berkeley/CRATE}.Comment: 33 pages, 11 figure

    Long working range light field microscope with fast scanning multifocal liquid crystal microlens array

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    The light field microscope has the potential of recording the 3D information of biological specimens in real time with a conventional light source. To further extend the depth of field to broaden its applications, in this paper, we proposed a multifocal high-resistance liquid crystal microlens array instead of the fixed microlens array. The developed multifocal liquid crystal microlens array can provide high quality point spread function in multiple focal lengths. By adjusting the focal length of the liquid crystal microlens array sequentially, the total working range of the light field microscope can be much extended. Furthermore, in our proposed system, the intermediate image was placed in the virtual image space of the microlens array, where the condition of the lenslets numerical aperture was considerably smaller. Consequently, a thin-cell-gap liquid crystal microlens array with fast response time can be implemented for time-multiplexed scanning

    The need for nursing instruction in patients receiving steroid pulse therapy for the treatment of autoimmune diseases and the effect of instruction on patient knowledge

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    <p>Abstract</p> <p>Background</p> <p>Many patients who receive steroid pulse therapy go home the same day or the day after steroid administration. Nursing instructions are important for improving patient knowledge related to their diseases and treatments, but the short hospital stay often prevents complete education and guidance regarding the given therapy. The purpose of this study was to investigate the need for nursing instruction in patients receiving steroid pulse therapy for the treatment of autoimmune diseases and the effect of instruction on patient knowledge of their disease and treatment.</p> <p>Methods</p> <p>Patients with systemic lupus erythematosus (SLE) and systemic sclerosis receiving steroid pulse therapy (N = 63) were recruited from a medical center in Taipei. A structured questionnaire was used for data collection before and after nursing instruction, and 1 week as well as 2 weeks after therapy. The need for nursing instruction and knowledge levels were validated using Cronbach's ι reliability test.</p> <p>Results</p> <p>There was a significant difference (<it>P </it>< 0.001) in the need for nursing instruction among the 4 time points. There was a positive correlation between the need for nursing instruction and body weight change, frequency of treatment, and distress, but there was a negative correlation with knowledge level (β = -0.012, <it>P </it>= 0.003) regarding symptoms. The knowledge level of subjects after nursing instruction was significantly higher than before nursing instruction (80 ¹ 14.31 vs. 70.06 ¹ 17.23, <it>P </it>< 0.001).</p> <p>Conclusions</p> <p>This study indicates that nursing instruction is needed by patients receiving steroid pulse therapy, and that by designing and administering nursing instructions according to the priority of patient symptoms, nurses can improve patient knowledge related to their diseases and treatments. In addition, the need for nursing instruction can be affected by patient characteristics.</p

    Differentiating impacts of non‐pharmaceutical interventions on non‐coronavirus disease‐2019 respiratory viral infections: Hospital‐based retrospective observational study in Taiwan

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    Background Physical distancing and facemask use are worldwide recognized as effective non-pharmaceutical interventions (NPIs) against the coronavirus disease-2019 (COVID-19). Since January 2020, Taiwan has introduced both NPIs but their effectiveness on non-COVID-19 respiratory viruses (NCRVs) remain underexplored. Methods This retrospective observational study examined electronic records at a tertiary hospital in northern Taiwan from pre-COVID (January–December 2019) to post-COVID period (January–May 2020). Patients with respiratory syndromes were tested for both enveloped (eg, influenza virus and seasonal coronavirus) and non-enveloped RVs (eg, enterovirus and rhinovirus) using multiplex reverse transcription polymerase chain reaction assays. Monthly positivity rates of NCRVs among adult and pediatric patients were analyzed with comparison between pre- and post-COVID periods. Results A total of 9693 patients underwent 12 127 multiplex RT-PCR tests. The average positivity rate of NCRVs reduced by 11.2% (25.6% to 14.4%) after nationwide PHIs. Despite the COVID-19 pandemic, the most commonly identified enveloped and non-enveloped viruses were influenza virus and enterovirus/rhinovirus, respectively. Observed reduction in NCRV incidence was predominantly contributed by enveloped NCRVs including influenza viruses. We did not observe epidemiological impacts of NPIs on non-enveloped viruses but an increasing trend in enterovirus/rhinovirus test positivity rate among pediatric patients. Our data were validated using Taiwan's national notification database. Conclusions Our frontline investigation suggests that the current NPIs in Taiwan might not effectively control the transmission of non-enveloped respiratory viruses, despite their protective effects against influenza and seasonal coronavirus. Health authorities may consider using hydrogen peroxide or chloride-based disinfectants as additional preventative strategies against non-enveloped respiratory viruses in the post-COVID-19 era

    YC-1 [3-(5Ј-Hydroxymethyl-2Ј-furyl)-1-benzyl Indazole] Inhibits Neointima Formation in Balloon-Injured Rat Carotid through Suppression of Expressions and Activities of Matrix Metalloproteinases 2 and 9

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    ABSTRACT Matrix metalloproteinases (MMPs), particularly MMP-2 and MMP-9, and postrevascularization production of vascular smooth muscle cells may play key roles in development of arterial restenosis. We investigated the inhibitory effect of 3-(5Ј-hydroxymethyl-2Ј-furyl)-1-benzyl indazole (YC-1), a benzyl indazole compound, on MMP-2 and MMP-9 activity in a ballooninjury rat carotid artery model. Injury was induced by inserting a balloon catheter through the common carotid artery; after 14 days, histopathological analysis using immunostaining and Western blotting revealed significant restenosis with neointimal formation that was associated with enhanced protein expression of MMP-2 and MMP-9. However, these effects were dosedependently reduced by orally administered YC-1 (1-10 mg/ kg). In addition, gelatin zymography demonstrated that increased MMP-2 and MMP-9 activity was diminished by YC-1 treatment. On the other hand, YC-1 inhibited hydrolysis of the fluorogenic quenching substrate Mca-Pro-Leu-Gly-Leu-DpaAla-Arg-NH 2 by recombinant MMP-2 and MMP-9 with IC 50 values ϭ 2.07 and 8.20 M, respectively. Reverse transcription-polymerase chain reaction analysis of MMP-2 and MMP-9 mRNA revealed that YC-1 significantly inhibited mRNA levels of MMPs. Finally, for the YC-1 treatment group, we did not observe elevation of cGMP levels using enzyme-linked immunosorbent assay, suggesting that YC-1 inhibition of neointimal formation is not through a cGMP-elevating pathway. These data show YC-1 suppression of neointimal formation is dependent on its influence on MMP-2 and MMP-9 protein, mRNA expression, and activity, but not through a cGMP-elevating effect. YC-1 shows therapeutic potential for treatment of restenosis after angioplasty. During the past 20 years, one focus of cardiovascular pharmaceutical research has been the development of drugs that inhibit intimal hyperplasia. Despite many attempts, no clinical trial has proven that there is an effective pharmacological solution to the problem Matrix metalloproteinases (MMPs) are a family of structurally related zinc-endopeptidases that degrade components of extracellular matrix associated with vascular remodeling during vascular injury-induced neointima formatio

    Effective Interventions and Decline of Antituberculosis Drug Resistance in Eastern Taiwan, 2004–2008

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    BACKGROUND: The Taiwan health authority recently launched several tuberculosis (TB) control interventions, which may have an impact on the epidemic of drug-resistant TB. We conducted a population-based antituberculosis drug resistance surveillance program in Eastern Taiwan to measure the proportions of notified TB patients with anti-TB drug resistance and the trend from 2004 to 2008. METHODS AND FINDINGS: All culture-positive TB patients were enrolled. Drug susceptibility testing results of the first isolate of each TB patient in each treatment course were analyzed. In total, 2688 patients were included, of which 2176 (81.0%) were new TB cases and 512 (19.0%) were previously treated cases. Among the 2176 new TB cases, 97 (4.5%) were retreated after the first episode of TB treatment within the study period. The proportion of new patients with any resistance, isoniazid resistance but not multidrug-resistant TB (resistant to at least isoniazid and rifampin, MDR-TB), and MDR-TB was 16.4%, 7.5%, and 4.0%, respectively, and that among previously treated cases was 30.9%, 7.9%, and 17.6%, respectively. The combined proportion of any resistance decreased from 23.3% in 2004 to 14.3% in 2008, and that of MDR-TB from 11.5% to 2.4%. CONCLUSIONS: The proportion of TB patients with drug-resistant TB in Eastern Taiwan remains substantial. However, an effective TB control program has successfully driven the proportion of drug resistance among TB patients downward
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