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Methods for reducing distributed subsample sizes have increasingly become popular statistical problems in the big data era. Existing works of optimal subsample selection on the massive linear and generalized linear models with distributed data sources have been solidly investigated and widely applied. Nevertheless, few studies have developed distributed optimal subsample selection procedures for quantile regression in massive data. In such settings, the distributed optimal subsampling probabilities and subset sizes selection criteria need to be established simultaneously. In this work, we propose a distributed subsampling technique for the quantile regression models. The estimation approach is based on a two-step algorithm for the distributed subsampling procedures. Furthermore, the theoretical results, such as consistency and asymptotic normality of resultant estimators, are rigorously established under some regularity conditions. The empirical evaluation and performance of the proposed subsampling method are conducted in simulation experiments and real data applications. • We develop a distributed optimal subsampling method for quantile regression. • The asymptotic properties of the proposed algorithms are rigorously established. • We provide a distributed least squares resampling covariance estimation method. [ABSTRACT FROM AUTHOR]

This paper introduces a sure screening method for ultrahigh-dimensional additive logistic models. With binary response variable, additive logistic model is very useful in social and biological research such as disease detection. The proposed feature screening procedure, ALNIS (nonparametric independence screening for additive logistic models), employs B-spline approximation to model the marginal effect, transforming nonparametric problems into parametric ones. This screening process ranks the nonparametric components according to their norms of the marginal likelihood estimate. Under appropriate conditions, the proposed method is shown to possess sure screening property with a vanishing false selection rate. In numerical studies, we use simulated data to compare the performance of the proposed approach with other seven methods that allow the existence of binary response. We further illustrate the proposed procedure by a real data analysis. Numerical comparison indicates that the proposed approach enjoys robustness and effectiveness under ultrahigh-dimensional additive logistic models. • Proposed a sure screening method for ultrahigh-dimensional additive logistic models • The proposed method possesses sure screening property under appropriate conditions • The proposed approach shows decent performance under additive logistic models [ABSTRACT FROM AUTHOR]

Linear regression is a fundamental and popular statistical method. There are various kinds of linear regression, such as mean regression and quantile regression. In this paper, we propose a new one called kernel density regression, which allows broad-spectrum of the error distribution in the linear regression. Our studies indicate that our method provides a better alternative than mean regression and quantile regression under many settings, particularly for asymmetrical heavy-tailed distribution or multimodal distribution of the error term. Furthermore, penalized likelihood estimator is proposed. Numerical studies also demonstrate the effectiveness and the flexibility of the proposed method. [ABSTRACT FROM AUTHOR]

Ultrahigh-dimensional variable screening plays an increasingly important part in diverse scientific areas and statistical researches. This paper mainly proposes two new feature screening approaches for varying coefficient models in ultrahigh-dimensional data analysis. One of them use the conditional quantile correlation corresponding to CQSIS τ as an utility measure of importance between the τ th quantile of response and predictor conditioning on the index variable, and the other utilizes the conditional distribution correlation, which corresponds to CQSIS, as an utility measure of significance between the response and predictor conditioning on the index variable. Under some regularization conditions, we establish the theoretical properties, including ranking consistency property and sure screening property. Simulation studies are conducted to evaluate the performance of the proposed methodologies. The simulations results show that our proposed approaches CQSIS τ and CQSIS significantly outperforms the existing methods in terms of varying coefficient models. We also illustrate the performance of CQSIS τ and CQSIS through two real-data examples. Both theoretical and numerical studies demonstrate the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

Highlights • We analyzed the role of radiotherapy in patients with limited WR-DLBCL. • Radiotherapy did not benefit patients with CR after R-CHOP. • Patients with nasopharyngeal primary tend to have poor outcome. Abstract The standard treatment of waldeyer's ring DLBCL remains controversial. This retrospective study was designed to evaluate the role of consolidation radiotherapy (RT) in patients with stage I/II diffuse large B-cell lymphoma (DLBCL) limited in Waldeyer's ring (WR). We included 72 patients, 42 were treated with immunochemotherapy alone (CT group) and 30 were treated with immunochemotherapy followed by radiotherapy (CT + RT group). All patients received at least 3 cycles of R-CHOP regimen and achieved complete remission (CR) after immunochemotherapy. After 53 months median follow-up time, the 5-year progression-free survival (PFS) rates in CT + RT group vs. CT group were 93.3% vs. 92.5% (P = 0.896), the 5-year overall survival (OS) rates were 96.7% vs. 94.4% (P = 0.649). Patients with oropharyngeal primary had relatively better 5-year PFS and OS rates compared to nasopharyngeal primary (PFS: 98.2% vs. 73.3%, p = 0.001; OS: 100% vs. 79.0%, p < 0.001). Moreover, the primary site was the only independent prognostic factor for PFS in the multivariate analysis (p = 0.012, HR 16.858 [95% CI: 1.883–150.933]). [ABSTRACT FROM AUTHOR]

Abstract: Purpose: In this randomized phase II study, we evaluated the efficacy of semustine added to CEOP regimen as induction chemotherapy in patients with stage IE/IIE extranodal NK/T-cell lymphoma, nasal type in the upper aerodigestive tract. Patients and methods: Seventy-five eligible patients were randomized to receive either CEOP or CEOP plus semustine followed by involved-field radiotherapy. Results: The overall response rate of induction chemotherapy was 57.9% in CEOP arm compared with 62.2% in CEOP plus semustine arm (P =0.71). With a median follow-up of 30.1months, 2-year overall survival was 73.3% and 62.2%, respectively (P =0.37). Toxicities in both arms were comparable and manageable. Through univariate and multivariate analysis, PS of 2, Stage IIE and elevated LDH level were identified to be adverse prognostic factors. A new prognostic index categorized three groups of patients (low risk, no adverse factors; intermediate risk, one factor; and high risk, 2 or 3 factors) with highly significant difference of prognosis. Two-year overall survival was 87.5%, 60.6% and 30%, respectively (P =0.0002). Conclusions: The addition of semustine to CEOP regimen was not associated with improved efficacy. More effective treatment needs to be explored in patients with intermediate or high risk. [Copyright &y& Elsevier]

[Display omitted] • SO 3 removal in simulated flue gas influenced by multi-factor was studied. • SO 3 transfer process from gas to liquid phase based on two-film theory was studied. • The tower structures had the greatest influence on SO 3 /sulfuric acid mist removal. • SO 3 removal process was controlled by gas–liquid film and gas film. • NH 3 and spraying flow promote SO 3 removal, SO 2 and slurry temperature are opposite. SO 3 /sulfuric acid mist is a strongly irritating pollutant presented in small quantities in flue gas, which poses a major threat to the power plants operation and atmospheric environment. In this study, SO 3 /sulfuric acid mist at different positions and after different spraying time of the small desulfurization tower were extracted and absorbed by isopropanol solution, and the SO 4 2- concentration was detected by barium-thorium titration. Then the SO 3 /sulfuric acid mist mass transfer model in desulfurization process was constructed on the basis of two-film theory to investigate the effects of different tower structures, spraying time and operating conditions on SO 3 /sulfuric acid mist removal in desulfurization tower. The results showed that the tower structures had the greatest influence on SO 3 /sulfuric acid mist removal, and the highest SO 3 /sulfuric acid mist removal efficiency was achieved after the spraying time of 0–20 min and at the flue gas distribution plate. Moreover, according to the results of SO 3 /sulfuric acid mist mass transfer model, SO 3 removing process was not controlled by solid dissolution instead of by gas–liquid film turning to gas film with flue gas residence time running in the tower. The model results also showed that SO 3 removing process was controlled by gas film for a very short period then turning to gas–liquid film immediately with spraying time accumulating in a specific tower position. Besides, it showed the increase of NH 3 concentration and spraying flow rate promoted the SO 3 /sulfuric acid mist removal, and the increase of SO 2 concentration and slurry temperature inhibited the SO 3 /sulfuric acid mist removal. [ABSTRACT FROM AUTHOR]

To address the multiple air pollution problems, the simultaneous abatement of NO x and VOCs in the existing NH 3 -SCR units has attracted considerable environmental attention. Although this method has lowered costs, saved space and facilitated manufacturing, its practical use is still constrained by various uncertainties, such as catalyst properties, reactant interactions, etc. Hence, this paper reviews the progress of research on the simultaneous abatement of NO x and VOCs from industrial furnaces using SCR technology in recent decades. Firstly, the effectiveness of various catalysts for the synergistic removing multiple-pollutant and various methods for changing the catalyst properties are evaluated. It is worth noting that NO x reduction and VOCs oxidation inevitably interact with each other, therefore the interaction mechanism of multiple reactants and the influence of reaction conditions on the synergistic removal efficiency are then discussed in detail. Additionally, the mechanism of catalyst deactivation in the presence of heavy metal, chloride, etc. and the corresponding regeneration methods are proposed. Finally, some recommendations regarding potential future investigative directions are given. Hopefully, this review can build a bridge between newly modified SCR catalysts and the transformation from single pollutant to synergistic multi-pollutant elimination, allowing for the commercial applications in the near future. [Display omitted] • Simultaneously abating NO x and VOCs by using SCR technology was fully reviewed. • Various SCR catalysts for synergistic pollutant removal were thoroughly analyzed. • The interactions between NO x reduction and VOCs oxidation were discussed in detail. • The catalyst deactivation and the corresponding regeneration method were concluded. • Challenges and prospects of synergistic multi-pollutant elimination were proposed. [ABSTRACT FROM AUTHOR]

Summary: The objective of this analysis was to evaluate the efficacy and treatment outcome of CHOP and CHOP combined with nitrosourea chemotherapy in natural killer (NK)/T-cell lymphoma of the nasal cavity. Sixty-three patients with NK/T-cell lymphoma of the nasal cavity were treated with CHOP or CHOP combined with oral nitrosourea chemotherapy between January 1997 and June 2005. By the Ann Arbor Lymphoma Staging Classification, 57 patients (90%) had Stage IE or IIE disease and six patients (10%) had Stage III or IV disease. All patients with Stage IE or IIE disease were intended to be treated curatively with combined chemoradiation; and patients who had Stage III or IV disease were treated with chemotherapy alone with curative intention. Chemotherapy consisted of: (1) up to six cycles of the standard CHOP based regimen, or (2) up to six cycles of the standard CHOP based regimen with oral Semustine dosed at 120mg (or Lomustine dosed at 100mg) on day 1 of each chemotherapy cycle. External beam radiation therapy was delivered by daily conventional fractionation by Co-60 or 6MVx linear accelerator for patients with Stage IE or IIE disease. The radiation dose to the tumor bed was between 36 and 50Gy with a median dose of 45Gy. Fifty-three patients received chemotherapy prior to radiation, and four patients were treated with involved field radiation before chemotherapy. The median follow up for all 44 surviving patients was 31 months (range: 6–104 months). The 2-year progression-free survival (PFS) and overall survival (OS) rates were 60% and 70%, respectively. The PFS and OS of patients who were treated with or without oral nitrosourea in addition to CHOP were 73% vs. 44% (P =0.035) and 75% vs. 64% (P =0.276), respectively. Nine patients with Stage IE or IIE diseases developed disease progression during their planned treatment and died within 10 months after the initiation of treatment; Six patients who achieved complete response (CR) after planned chemoradiation developed systemic recurrence and died at 13–48 months despite salvage treatment; one patient died of Hemophagocytic Syndrome during radiotherapy after achieving CR from chemotherapy. Three patients with Stage III or IV disease died during chemotherapy or during salvage treatment at 2, 4, and 19 months, respectively. Among the 59 patients who received chemotherapy as their initial treatment, 29, 6, 12, and 12 patients had complete response (CR), partial response (PR), stable disease (SD), and progressive disease (PD) respectively after chemotherapy. The 2-year overall survival rates for these four groups of patients were 100%, 75%, 60%, and 17%, respectively (P <0.0001). Multivariate analysis revealed that International Prognostic Index (IPI) for Lymphoma, perforation of nasal septum as a presenting symptom, “B” symptoms, ECOG performance, as well as response after chemotherapy, were significant independent prognostic factors for this group of patients. The extent of response after induction chemotherapy is significantly related to the treatment outcome of patients with nasal NK/T-cell lymphoma. CHOP based chemotherapy combined with oral nitrosourea followed by involved field radiotherapy may provide improved treatment results compared to conventional CHOP chemotherapy and radiation. This strategy needs to be optimized and tested in a prospective trial for its efficacy. [Copyright &y& Elsevier]

• Point-of-need diagnostics are required to contain the spread of SARS-CoV-2. • Recombinase-based assays rapidly detect SARS-CoV-2 in clinical samples. • The two isothermal amplification methods tested showed promising diagnostic efficiency. • The incorporation of these techniques in a 'suitcase laboratory' may facilitate remote deployment. The democratization of diagnostics is one of the key challenges towards containing the transmission of coronavirus disease 2019 (COVID-19) around the globe. The operational complexities of existing PCR-based methods, including sample transfer to advanced central laboratories with expensive equipment, limit their use in resource-limited settings. However, with the advent of isothermal technologies, the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is possible at decentralized facilities. In this study, two recombinase-based isothermal techniques, reverse transcription recombinase polymerase amplification (RT-RPA) and reverse transcription recombinase-aided amplification (RT-RAA), were evaluated for the detection of SARS-CoV-2 in clinical samples. A total of 76 real-time reverse transcription PCR (real-time RT-PCR) confirmed COVID-19 cases and 100 negative controls were evaluated to determine the diagnostic performance of the isothermal methods. This investigation revealed equally promising diagnostic accuracy of the two methods, with a sensitivity of 76.32% (95% confidence interval 65.18–85.32%) when the target genes were RdRP and ORF1ab for RT-RPA and RT-RAA, respectively; the combination of N and RdRP in RT-RPA augmented the accuracy of the assay at a sensitivity of 85.53% (95% confidence interval 75.58–92.55%). Furthermore, high specificity was observed for each of the methods, ranging from 94.00% to 98.00% (95% confidence interval 87.40–9.76%). Considering the diagnostic accuracies, both RT-RPA and RT-RAA appear to be suitable assays for point-of-need deployment for the detection of the pathogen, understanding its epidemiology, case management, and curbing transmission. [ABSTRACT FROM AUTHOR]

Bitumen materials will occur a physical hardening effect when stored isothermally in a low-temperature environment, and ignoring the physical hardening factor has become one of the important reasons for premature cracking of asphalt pavement during the service period. This paper investigates the response of bitumen binder and bitumen mastic to physical hardening effects at different storage temperatures and times using the bending beam rheometer and dynamic shear rheometer. The response of the material to physical hardening effects is analyzed through temperature index system changes, mathematical model fitting, and stiffness master curve fitting. Results indicate that the response of the material to physical hardening effects can be classified into two stages: the rapid growth and the gradual stabilization periods. The response time of these two stages is related to factors such as aging degree and storage temperature. The physical hardening effect will cause the temperature loss of the material at low temperature, and its influence law on T S 60 = 300 MPa and T m 60 = 0.300 is different. It is recommended to extend the isothermal storage time specified in the test from 1 h to 9 h, considering the time cost and the change in temperature index. Moreover, the stiffness master curve study revealed the occurrence of the "tail drift" phenomenon. • Physical hardening effects cause temperature loss in bitumen, even over a grade. • Recommend extending BBR test storage to 9 h for better scientific validity. • "Tail drift" occurs during the fitting of the stiffness master curve. • The Logistic model can well fit the S and m values in the physical hardening process. [ABSTRACT FROM AUTHOR]

Summary Background The early detection and identification of pathogens in central nervous system viral infections associated with neurological disease increases the survival rate. However, the limitations of current diagnostic methods contribute to a lack of proper diagnosis in 62% of patients. Therefore, a robust method for detecting multiple viruses in a single reaction with high specificity, throughput, and speed is required. Methods A multiplex PCR Mag-Array (MPMA) system was developed that integrates three strategies: chimeric primer design, temperature switch PCR, and MagPlex-TAG techniques. The MPMA was used to amplify 13 target viral sequences simultaneously, with plasmids containing specific viral sequences as standard samples. To evaluate its clinical performance, 177 cerebrospinal fluid (CSF) samples were tested. Results The MPMA system presented high specificity and efficiency in detecting a control panel of 13 plasmids. Among 177 CSF samples, consistent results were achieved for 19 samples pre-tested using a commercial kit. Viral pathogens were found in 28/138 undiagnosed samples, with herpes simplex viruses (HSV-1 and HSV-2) being predominant. The 20 non-infectious samples revealed negative results. Compared to sequencing methods, sensitivity for detecting HSV-1 and HSV-2 was 100% and 98.78%, respectively, and specificity was 100% and 98.22%, respectively. Conclusions A robust MPMA system that can simultaneously and reliably detect 13 meningoencephalitis-associated viruses with high specificity, throughput, and speed has been developed. [ABSTRACT FROM AUTHOR]

Abstract: Accurate and rapid quantitation of Human immunodeficiency virus type 1 (HIV-1) RNA levels is a critical aspect in estimating the effect of antiviral therapy and establishing therapeutic schedule. Thus, for the first time, a rapid quantitative reverse transcription-loop-mediated isothermal amplification (RT-LAMP) was designed to quantitate HIV-1 RNA. The results showed that the dynamic range was from 2.5×102 to 107 copies with a coefficient of determination (R2) of 0.991, and the limit of detection of RT-LAMP by Probit analysis at the 95% detection level was 196 copies. The intra-assay coefficient of variation (CV) ranged from 0.67% to 2.08% at 107 copies and 7.25% to 12.97% at 250 copies. The CVs of inter-assay were 2.39% and 13.93% for the high and low copy numbers, respectively. No cross-reaction with Human immunodeficiency virus type 2 (HIV-2), Human T lymphotrophic virus type 1 (HTLV-1) and Hepatitis C virus (HCV) was observed and a good agreement between the RT-LAMP method and the real-time reverse transcription-polymerase chain reaction (qRT-PCR) test was achieved. This proposed RT-LAMP method could be useful for rapid diagnosis of high risk group and pharmacodynamic assessment of anti-HIV drug, especially in less-equipped laboratories of impoverished areas. [Copyright &y& Elsevier]

Abstract: A rapid and simple method for the detection of drug-resistant Mycobacterium tuberculosis is critical for the efficient treatment and control of this pathogen in developing country. Here we developed a single multiplex amplification refractory mutation system (M-ARMS) PCR, in which chimeric-primer and temperature switch PCR (TSP) strategy were included. Using this method, we detected rifampin resistance-associated mutations at codons 511, 516, 526 and 531 in the rifampin resistance-determining region of rpoB gene. The performance of M-ARMS-PCR assay was evaluated with 135 cultured isolates of M. tuberculosis. The sensitivity and specificity were 94.2% and 100%, respectively, compared with direct DNA sequencing, and 86.67% and 89.71%, respectively, compared with culture-based phenotypic drug susceptibility testing. Therefore, this newly-developed M-ARMS-PCR method is useful and efficient with an intended application in provincial Centers for Disease Control and Prevention for rapid detection of rifampin resistance-associated mutations. [Copyright &y& Elsevier]

We report the 2.7 A˚ resolution structure of a chimeric rhinovirus, MN-III-2, that displays part of the HIV-1 gp120 V3 loop and elicits HIV-neutralizing antibodies. The V3 loop insert is dominated by two type I β turns. The structures of two adjacent tripeptides resemble those of analogous segments in three Fab/V3 loop peptide complexes. Although two of the three corresponding antibodies bind and neutralize MN-III-2 well, only one of the three can bind without significant rearrangement. These results suggest that the V3 loop insert: (1) can share some local conformational similarity to V3 loop sequences presented on different structural frameworks; (2) must be able to adopt multiple conformations, even in a relatively constrained environment; and (3) may mimic the conformational variability of the epitope on HIV-1, increasing the likelihood of eliciting appropriate neutralizing immune responses. [Copyright &y& Elsevier]