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Data reduction is crucial in order to turn large datasets into information, the major purpose of data science. The classic and richer area of dimensionality reduction (DR) has traditionally been based on feature extraction by combining primary features in a linear fashion, aiming to preserve or maintain covariance/correlations between the features. Nonlinear alternatives have been developed, including information-theoretic approaches using mutual information as well and conditional entropy based on target features. Here, we further this approach to feature selection or reduction strategy based on the concept of conditional Shannon entropy of two random variables. Novel results include (a) a dimensionality reduction method based on conditional entropy between predictors themselves along two variants, disregarding the influence of the target feature; (b) an error-prevention method inspired by error-detection and correction in information theory for DR with genomic data that can be used for abiotic data as well; and (c) a comparative assessment of the performance of several machine learning models on input features selected by these methods. We assess the quality of the techniques based on their performance in solving three application problems (Malware Classification, BioTaxonomy, and Noisy Classification) of various degrees of difficulty with competitive outcomes. Some useful heuristics arise from the analysis of the results and also suggest some problems of interest for further research.

Deep generative models with a specific variational autoencoding structure are capable of estimating parameters for the multidimensional logistic 2-parameter (ML2P) model in item response theory. In this work, we incorporated Q-matrix and variational autoencoder (VAE) to estimate item parameters with correlated and independent latent abilities, and we validate Q-matrix via the root mean square error (RMSE), bias, correlation, and AIC and BIC test score. The incorporation of a non-identity covariance matrix in a VAE requires a novel VAE architecture, which can be utilized in applications outside of education such as players performance evaluation, clinical trials assessment. Moreover, results show that the ML2P-VAE method is capable of estimating parameters and validating Q-matrix for models with a large number of latent variables with low computational cost, whereas traditional methods are infeasible for data with high-dimensional latent traits.

Dimensional analysis transforms a dimensionally homogeneous model into its simplest form; the number of input variables can be reduced. Such a reduction is very helpful in statistical design and an...

We consider a general framework for constructing non-linear generators by adding a (32-bit or larger) pseudo-random number generator (PRNG) as a baseline generator to the basic RC4 design, in which an index-selection scheme similar to RC4 is used. We refer to the proposed design as the eRC (enhanced/extended RC4) design. We discuss several advantages of adding a good baseline generator to the RC4 design, including new updating schemes for the auxiliary table. We consider some popular PRNGs with the nice properties of high-dimensional equi-distribution, efficiency, long period, and portability as the baseline generator. We demonstrate that eRC generators are very efficient via extensive empirical testing on some eRC generators. We also show that eRC is flexible enough to choose minimal design parameters for eRC generators and yet the resulting eRC generators still pass stringent empirical tests, which makes them suitable for both software and hardware implementations.

Pseudo-random numbers (PRNs) are the basis for almost any statistical simulation and this depends largely on the quality of the pseudo-random number generator (PRNG) used. In this study, we used some results from number theory to propose an efficient method to accelerate the computer search of super-order maximum-period multiple recursive generators (MRGs). We conduct efficient computer searches and identify many efficient and portable MRGs of super-orders, 40751, 50551, and 50873; which respectively have equi-distribution property up to 40751, 50551, and 50873 dimensions, and period lengths of approximately 10380278.1, 10471730.6, and 10474729.3. Using the generalized Mersenne prime algorithm, we extend some known results of some efficient, portable and maximum-period MRGs. In particular, the DX/DL/DS/DT large-order generators are extended to super-order generators. An extensive empirical evaluation shows that these generators behave well when tested with the stringent Small Crush and Crush batteries of the TestU01 package.

Coronavirus disease 2019 (COVID-19) has triggered an enormous number of discussion topics on social media Twitter. It has an impact on the global health system and citizen responses to the pandemic. Multiple responses (replies, favorites, and retweets) reflect the followers’ attitudes and emotions towards these tweets. Twitter data such as these have inspired substantial research interest in sentiment and social trend analyses. To date, studies on Twitter data have focused on the associational relationships between variables in a population. There is a need for further discovery of causality, such as the influence of sentiment polarity of tweet response on further discussion topics. These topics often reflect the human perception of COVID-19. This study addresses this exact topic. It aims to develop a new method to unveil the causal relationships between the sentiment polarity and responses in social media data. We employed sentiment polarity, i.e., positive or negative sentiment, as the treatment variable in this quasi-experimental study. The data is the tweets posted by nine authoritative public organizations in four countries and the World Health Organization from December 1, 2019, to May 10, 2020. Employing the inverse probability weighting model, we identified the treatment effect of sentiment polarity on the multiple responses of tweets. The topics with negative sentiment polarity on COVID-19 attracted significantly more replies (69±49) and favorites (688±677) than the positive tweets. However, no significant difference in the number of retweets was found between the negative and positive tweets. This study contributes a new method for social media analysis. It generates new insight into the influence of sentiment polarity of tweets about COVID-19 on tweet responses.

Lead time plays an important role in many areas, including supply chain, economics, and marketing. A conventional assumption in most stochastic lead-time inventory models is that the lead t...

This study examined the utility of the Chinese version Modified Checklist for Autism in Toddlers (C-M-CHAT) in a high-risk sample. This study recruited 236 children aged from 18 to 47 months old in rural area of Southern Taiwan, including 113 children with Autism Spectrum Disorder (ASD) and 123 children with Developmental Delay (DD). Using failing any four of the 23 C-M-CHAT items as cutoff, it showed a sensitivity of 77.0% and a specificity of 72.4%. The positive predictive value (PPV) was 71.9% while the negative predictive value (NPV) was 77.4%. Using failing any three of the 14 new critical items–referred to as the “Brief 14”–as cutoff, it yielded a sensitivity of 70.8% and a specificity of 82.1%. The PPV of the “Brief 14” was 78.4% while the NPV was 75.4%. The preliminary results of the C-M-CHAT and the “Brief 14” performance demonstrated an acceptable predictive validity and promising utility for use in high-risk, rural populations in Taiwan.

Background/Purposes: Human rhinovirus type C (HRV-C) has been associated with asthma exacerbation (AE) in children in several countries. However, in Taiwan the association between HRV, especially HRV-C, and AE in children has yet to be elucidated. We sought to investigate the prevalence of respiratory viruses in children with acute lower respiratory tract infection (ALRTI) in Taiwan and the association between different types of HRV and AE in children. Methods: This prospective study was conducted from 2011 to 2013, and enrolled children with ALRTI, including an asthma exacerbation group (AE; n = 28) and a Non-asthma group (n = 66). Viruses were detected by culture, reverse transcription-polymerase chain reaction, and molecular sequencing of nasopharyngeal swabs. Results: The prevalence of identified respiratory viruses was 78.6% in the AE group and 65.2% in the Non-asthma group. The prevalence rates of HRV and HRV-C were significantly higher in the AE group than in the Non-asthma group (67.9% vs. 33.3% in HRV, p = 0.002; and 50% vs. 15.2% in HRV-C, p

Dioscorins, the primary storage proteins in yam tubers, of different species exhibited varying immunomodulatory activities in mice. We inferred that this might be attributed to the various isoforms in the yam tubers.We aimed to investigate the antiallergic potential of the Class A dioscorins of various yam species using the ovalbumin (OVA)-induced murine allergy model.We purified the recombinant Class A dioscorins (rDioscorins) of various yam species from Escherichia coli and evaluated their antiallergic potential by enzyme-linked immunosorbent assay.The Class A rDioscorins of various yam species suppressed allergic reactions by significantly decreasing the serum IgE and histamine levels. The serum IFN-γ and IgG2a levels significantly increased in all rDioscorin-treated mice. The splenocytes of the rDioscorin-treated mice also exhibited upregulated IFN-γ secretion in response to ConA stimulation. By contrast, the serum IL-5 levels decreased to basal levels in mice treated with Class A rDioscorins and the amount of IL-5 produced by splenocytes decreased in response to ConA stimulation.The Class A rDioscorins suppress allergic reactions, possibly through modulating an imbalanced Th1/Th2 immune response to OVA by promoting Th1 cell responses. Furthermore, the Class A rDioscorins of various yam species exhibited similar immunomodulatory activities in OVA-sensitized mice, which were different from the activities demonstrated by native dioscorins, suggesting that distinct immunomodulatory effects of native dioscorins on mice were attributed to the various isoforms in the yam tubers.The Class A dioscorins of various yam species exhibit antiallergic activity and are potential immunotherapeutic agents for treating IgE-mediated hypersensitivity.

BACKGROUND: Dioscorins are the major storage proteins of yam tubers. However, the molecular nature of their heterogeneity in tubers has not been fully elucidated. In this study the authors isolated the dioscorin gene families of Dioscorea japonica and Dioscorea pseudojaponica, performed matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF-MS) and elucidated which dioscorin isoforms are the major constituents in tubers. RESULTS: The dioscorin gene families of D. japonica (Dj-dioA1-Dj-dioA4, Dj-dioB1 and Dj-dioB2) and D. pseudojaponica (Dp-dioA1-Dp-dioA5 and Dp-dioB1) were cloned from cDNA libraries of yam tubers. The dioscorins isolated from Dioscorea alata (Da-dioscorins), D. japonica (Dj-dioscorins) and D. pseudojaponica (Dp-dioscorins) were mainly monomers, with a few dimers. The monomers contained one intramolecular disulfide bond (Cys28-Cys187) and belonged to Class A dioscorins with two cysteine residues. The dimers consisted of Class B dioscorins with one intermolecular disulfide bond (Cys40-Cys40). Results of MALDI-TOF-MS revealed that the Da-dioscorins were mainly encoded by Da-dioA2, Da-dioA3 and Da-dioA4. The majority of the Dj-dioscorins were encoded by Dj-dioA1, Dj-dioA2, Dj-dioA3 and Dj-dioB2. The Dp-dioscorins mainly comprised proteins encoded by Dp-dioA1, Dp-dioA3, Dp-dioA4, Dp-dioB1 and Dp-dioB2. CONCLUSION: Determination of the constituents of dioscorin isoforms in yam tubers provides a basis for future studies of their physiological and biomedical functions. © 2012 Society of Chemical Industry

Dioscorins, the major storage proteins in yam tubers, exhibit biochemical and immunomodulatroy activities. To investigate the potential application of dioscorins in biomedical research, we expressed the dioscorin genes Dj-dioA3 and Dp-dioA2 from Dioscorea japonica and Dioscorea pseudojaponica , respectively, in E. coli and routinely obtained approximately 15 mg proteins per liter Escherichia coli culture (mg/L) to 30 mg/L of rDj-dioscorinA3 and 4 to 8 mg/L of rDp-dioscorinA2. Western blot analyses revealed that both recombinant dioscorins contained epitopes with similar antigenicities to those of the native dioscorins. Results from dithiothreitol (DTT) treatment followed by monobromobimane (mBBr) staining showed that both recombinant dioscorins, like the native dioscorins, contain an intramolecular disulfide bond between Cys 28 and Cys 187 residues. Circular dichroism spectroscopy findings indicated that the secondary structural contents of the recombinant dioscorins showed high similarity to those of their corresponding native dioscorins. Both recombinant dioscorins, like the native dioscorins, exhibited 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and Toll-like receptor 4 signaling activities, and stimulated the phagocytosis of E. coli by macrophage. Overall, our results indicated that substantial amounts of recombinant dioscorins can be purified easily from E. coli and that these recombinant dioscorins are appropriate for application in future investigations of the biomedical functions of dioscorins.

Dioscorins are the major storage proteins of yam tubers. However, the molecular nature of their heterogeneity in tubers has not been fully elucidated. In this study the authors isolated the dioscorin gene families of Dioscorea japonica and Dioscorea pseudojaponica, performed matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF-MS) and elucidated which dioscorin isoforms are the major constituents in tubers.The dioscorin gene families of D. japonica (Dj-dioA1-Dj-dioA4, Dj-dioB1 and Dj-dioB2) and D. pseudojaponica (Dp-dioA1-Dp-dioA5 and Dp-dioB1) were cloned from cDNA libraries of yam tubers. The dioscorins isolated from Dioscorea alata (Da-dioscorins), D. japonica (Dj-dioscorins) and D. pseudojaponica (Dp-dioscorins) were mainly monomers, with a few dimers. The monomers contained one intramolecular disulfide bond (Cys(28)-Cys(187)) and belonged to Class A dioscorins with two cysteine residues. The dimers consisted of Class B dioscorins with one intermolecular disulfide bond (Cys(40)-Cys(40)). Results of MALDI-TOF-MS revealed that the Da-dioscorins were mainly encoded by Da-dioA2, Da-dioA3 and Da-dioA4. The majority of the Dj-dioscorins were encoded by Dj-dioA1, Dj-dioA2, Dj-dioA3 and Dj-dioB2. The Dp-dioscorins mainly comprised proteins encoded by Dp-dioA1, Dp-dioA3, Dp-dioA4, Dp-dioB1 and Dp-dioB2.Determination of the constituents of dioscorin isoforms in yam tubers provides a basis for future studies of their physiological and biomedical functions.

Background/PurposeThis aim of this study was to assess the clinical manifestations, the microorganisms involved and their antibiotic resistance in children hospitalized due to acute lobar nephronia (ALN) and non-ALN community-acquired urinary tract infections (UTIs).MethodsWe retrospectively reviewed the records of 265 previously healthy children hospitalized due to a first-episode of community-acquired febrile UTI between July 2004 and June 2007. Based on the results of renal ultrasonography and computed tomography, they were divided into ALN and non-ALN groups. Their demographic and clinical characteristics, distribution of microorganisms, and their antimicrobial resistance were analyzed.ResultsOf the total number of cases of children admitted with a first-episode community-acquired UTI, 19.2% (n=51) were diagnosed as ALN. Children with ALN were older (1.86 years vs. 0.81 years; p < 0.01), had longer periods of fever before admission (4.7 days vs. 1.4 days; p < 0.01), higher peak body temperatures (39.5°C vs. 38.9°C; p < 0.01), higher white cell counts (18.86 × 109/L vs. 15.08 × 109/L; p < 0.01) and higher C-reactive protein levels (9.0 mg/dL vs. 3.5 mg/dL; p < 0.01) compared with non-ALN children. Fever also persisted for longer after the start of antibiotic treatment in the ALN children (2.7 days vs. 1.4 days: p < 0.01) and they required longer hospital stays and incurred higher medical costs. The major pathogen found in ALN was E. coli (90%). The E. coli isolated from ALN children was more resistant to cotrimoxazole and ciprofloxacin than those from non-ALN children.ConclusionALN is not uncommon in children with a first-episode febrile UTI. They have a prolonged clinical course, higher inflammatory parameters, longer hospital stays and incur higher medical costs. E. coli is the major pathogen isolated from these children.

[Figure][1] [![Graphic][3] ][3][![Graphic][4] ][4] A 9-year-old girl presented with cervical mass 2 months before heart failure. Her grandfather had died of tuberculosis 6 years previously. Tuberculous lymphadenitis was proved by biopsy of a neck mass, and chest radiography