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To estimate dynamic functional connectivity for functional magnetic resonance imaging (fMRI) data, two approaches have dominated: sliding window and change point methods. While computationally feasible, the sliding window approach has several limitations. In addition, the existing change point methods assume a Gaussian distribution for and linear dependencies between the fMRI time series. In this work, we introduce a new methodology called Vine Copula Change Point (VCCP) to estimate change points in the functional connectivity network structure between brain regions. It uses vine copulas, various state-of-the-art segmentation methods to identify multiple change points, and a likelihood ratio test or the stationary bootstrap for inference. The vine copulas allow for various forms of dependence between brain regions including tail, symmetric and asymmetric dependence, which has not been explored before in the dynamic analysis of neuroimaging data. We apply VCCP to various simulation datasets and to two fMRI datasets: a reading task and an anxiety inducing experiment. In particular, for the former dataset, we illustrate the complexity of textual changes during the reading of Chapter 9 in Harry Potter and the Sorcerer's Stone and find that change points across subjects are related to changes in more than one type of textual attributes. Further, the graphs created by the vine copulas indicate the importance of working beyond Gaussianity and linear dependence. Finally, the R package vccp implementing the methodology from the article is available from CRAN. for this article are available online. [ABSTRACT FROM AUTHOR]

Reproducibility, the ability to reproduce the results of published papers or studies using their computer code and data, is a cornerstone of reliable scientific methodology. Studies where results cannot be reproduced by the scientific community should be treated with caution. Over the past decade, the importance of reproducible research has been frequently stressed in a wide range of scientific journals such as Nature and Science and international magazines such as The Economist. However, multiple studies have demonstrated that scientific results are often not reproducible across research areas such as psychology and medicine. Statistics, the science concerned with developing and studying methods for collecting, analyzing, interpreting and presenting empirical data, prides itself on its openness when it comes to sharing both computer code and data. In this article, we examine reproducibility in the field of statistics by attempting to reproduce the results in 93 published papers in prominent journals using functional magnetic resonance imaging (fMRI) data during the 2010–2021 period. Overall, from both the computer code and the data perspective, among all the 93 examined papers, we could only reproduce the results in 14 (15.1%) papers, that is, the papers provide both executable computer code (or software) with the real fMRI data, and our results matched the results in the paper. Finally, we conclude with some author-specific and journal-specific recommendations to improve the research reproducibility in statistics. [ABSTRACT FROM AUTHOR]

Frequency control can be realized via laminating a novel smart material: light activated shape memory polymer (LASMP) whose Young's modulus varies under light field. In this work, frequency control of plates with LASMP patches is studied. Validation is fulfilled by comparing present results with FEM results for both beams and plates. Furthermore, frequency analysis of plate with LASMP patch pair whose location or size varies is also investigated. Finally, the optimal frequency control scheme of the composite plate is presented and studied in detail. Results show that the optimal scheme has obvious control effect on natural frequency of the plate. [ABSTRACT FROM AUTHOR]

Confronting the outbreak of COVID-19, this cross-sectional study was aimed to assess psychological status of temporomandibular disorders (TMD) patients, orthodontic patients and the general population in China during the pandemic. An online anonymous questionnaire was developed in Chinese, including the individual background information, the perception of the epidemic, and level of anxiety and depression through Kessler Psychological Distress Scale (K10). The respondents were divided into ORTHO group, TMD group and Control group. Descriptive analysis and multiple linear regression modelling were performed. In total, 1241 valid questionnaires were collected, covering 587 orthodontic patients and 220 TMD patients. It is shown that the overall mental health is not quite optimistic during the COVID-19 pandemic with the mean score of K10 being 18.65. TMD patients have higher level of anxiety and depression than orthodontic patients as well as the general population. Younger age, female gender, having close contact with individuals from Hubei province, higher self-rated infection possibility, concern about psychological barriers and distrust are negatively affecting patients' psychological status. Mental health care should be emphasized when hospitals and clinics reopen after the COVID-19 pandemic, especially to patients with these relevant characteristics. [ABSTRACT FROM AUTHOR]

Postmortem characteristics of Patinopecten yessoensis adductor muscle (PYAM) were evaluated by biochemical, chemical and textural changes during iced storage for 14 days. Triphosphate (ATP) and its breakdown products, K-value, total volatile basic nitrogen (TVB-N), pH, water-holding capacity (WHC), color, texture, protein degradation and cathepsin activities were monitored. K-value increased linearly from 5.9 ± 0.9% at day 0 to 28.1 ± 2.4% at day 2 and 70.2 ± 1.8% at day 12. Spoilage indicator TVB-N (mg/100 g) increased from 10.0 ± 0.6 to 34.6 ± 3.1 at day 12. Textural parameters (e.g., hardness, chewiness, springiness, adhesiveness, and shear force) followed a declining trend over the storage. The WHC decreased from 85.1 ± 3.1% at day 0 to 70.5 ± 1.8% at day 12. SDS-PAGE result indicated that proteolysis occurred in actin and myosin heavy chain (MHC) at day 14. Both cathepsin B and L increased throughout the iced storage, peaking at 1.47-fold and 1.08-fold, respectively, suggesting that cathepsin B and L played important roles in the deterioration of PYAM quality. The overall results indicated that PYAM was suitable to be consumed raw within the first 2 days, and to be processed in no more than 11 days. [ABSTRACT FROM AUTHOR]

For mapping a large area with airbrone synthetic aperture radar (SAR), very high-resolution (VHR) images using radargrammtry, block adjustment, where strips and blocks of images are processed together, is a preferred method for geometric processing with the advantage of reducing the needed number of ground control points (GCPs). However, the weak intersection geometry between adjacent images from the same strip conflicts with the solvability of the iterative least squares adjustment. In order to overcome this challenge, this article focuses on block adjustment with airbrone SAR VHR images using r-D model combined with trajectory constraints from azimuth tie points (ATPs). Initially, r-D model is briefly introduced. Then, the trajectory constraint equations are proposed and formulated with ATPs. Finally, an improved solution method is applied to increase the computational efficiency of the least squares process. Experiments are carried out using Chinese airbrone SAR VHR images over Shanxi Yanliang, China. The results show that the proposed method can effectively improve the accuracy of block adjustment in both range and elevation direction, with the root mean square error reduced from 0.440 to 0.253 m in range direction and from 0.501 to 0.256 m in elevation direction, respectively. The effects of the distribution and number of GCPs are also investigated, based on which some rules-of-thumb are derived. [ABSTRACT FROM PUBLISHER]

The use of mycobacteriophage D29 to treat Mycobacterium tuberculosis (MTB)-infected macrophages results in significant inhibitory activity. This study aims to explore the novel treatment strategy of intracellular mycobacterial infection from the point of view of phages. We investigated the dynamic phagocytosis and elimination of D29 by macrophages, measured the titer of D29 inside and outside MTB within macrophages by fluorescence quantitative PCR, and detected the levels of interleukin 12 (IL-12) and nitric oxide (NO) in the culture supernatants of D29-infected macrophages by ELISA. Results showed that the activity of D29 phagocytosed by macrophages was significantly lower than that of D29 phagocytosed by MTB-infected macrophages. The titer of D29 that infected intracellular MTB ranged from 109 pfu to 104 pfu. The titer of D29 inside and outside intracellular MTB transiently increased when MTB-infected macrophages were incubated with D29 for 40 and 50 min; then, a large number of D29 were eliminated by macrophages. The levels of IL-12 and NO had no significant differences versus the negative control but were significantly lower compared with the lipopolysaccharide (LPS) positive control. These results suggest D29 has no effect on the immune function of macrophages and that high phage titer must be administered repeatedly if D29 is applied to treat intracellular MTB infection. [ABSTRACT FROM AUTHOR]

A rapid, simple, and sensitive LC-MS/MS method was developed and validated for the determination of trimetazidine in rat plasma, using lidocaine as the internal standard (IS). The chromatographic separation was accomplished on a Atlantis dC18 column (150 × 2.1 mm, 5 µm) with the mobile phase consisting of acetonitrile and 10 mM ammonium formate (3:7, v/v) (pH 3.05, adjusted with formic acid). Plasma samples were deproteined with acetonitrile (1:3) and 3 μL of the supernatant was injected into the system. The retention times of trimetazidine and IS were approximately 1.45 min and 2.10 min, respectively. Calibration curves were linear over the concentration range of 0.5–500 ng/mL (1000 fold). The intra- and inter-batch precision, accuracy, and the relative standard deviation were all <15%. This method was successfully applied to determine trimetazidine concentrations in rat plasma. [ABSTRACT FROM PUBLISHER]

The identification of Wheel/Rail Force (WRF) based on acceleration is a cheaper and convenient way to ensure safe operation. For this purpose, this paper describes an approach for the estimation of Vertical Wheel/Rail Force (VWRF) using dynamic signals from a track inspection train (TIT). Based on the vehicle dynamics theory, a VWRF estimation model is established, by which VWRF can be estimated with the measured vehicle acceleration. Rolling angle is a non-constant and hard-measured value which will affect estimation results. By deducing its relation with the difference between left and right track profiles, it can be got through the Vertical Axle Box Acceleration (VABA) and the length of the axle box. VWRF cannot be estimated only by filtering the Axle Box Acceleration (ABA). The mass participating in vibration (PVM) also has a great influence on it. With many tests and calculations, the relationship between the PVM and the wheelset mass is concluded, which made the estimation results much more accurate. The proposed method provides the basis for online high-precision estimate WRF and ensures safe operation. By comparing with a commercial WRF Inspection System, the railway application results identified that the proposed method can produce a satisfactory result. [ABSTRACT FROM AUTHOR]

We used eye-tracking to evaluate multiple facial context processing and event-related potential (ERP) to evaluate multiple facial recognition in individuals at clinical high risk (CHR) for psychosis. In total, 173 subjects (83 CHRs and 90 healthy controls [HCs]) were included and their emotion perception performances were accessed. A total of 40 CHRs and 40 well-matched HCs completed an eye-tracking task where they viewed pictures depicting a person in the foreground, presented as context-free, context-compatible, and context-incompatible. During the two-year follow-up, 26 CHRs developed psychosis, including 17 individuals who developed first-episode schizophrenia (FES). Eighteen well-matched HCs were made to complete the face number detection ERP task with image stimuli of one, two, or three faces. Compared to the HC group, the CHR group showed reduced visual attention to contextual processing when viewing multiple faces. With the increasing complexity of contextual faces, the differences in eye-tracking characteristics also increased. In the ERP task, the N170 amplitude decreased with a higher face number in FES patients, while it increased with a higher face number in HCs. Individuals in the very early phase of psychosis showed facial processing deficits with supporting evidence of different scan paths during context processing and disruption of N170 during multiple facial recognition. [ABSTRACT FROM AUTHOR]

A new way to prepare BiFeO3nano-powders by low-heating temperature solid state precursor method is presented in this paper. Room-temperature solid state reaction was adopted to prepare the precursors, which were further calcined in low-heating temperature at 500°C to synthesize nano-BiFeO3. The particle size of BiFeO3, ranging from 18 to 80 nanometers, can be effectively controlled by different alkali in raw materials. Owing to the quantum size effect, the optical band gaps and magnetic characteristics of BiFeO3increased with the decreasing particle size. [ABSTRACT FROM AUTHOR]

Conclusion. A trans-superior meatus endoscopic approach to treat diseases in the sphenoid sinus and sellar area is a safe, minimally traumatic, and effective method. Objective: To avoid complications, we explored the use of the superior meatus and superior turbinate in the endoscope approach to the sphenoid sinus and sellar area. Patients and methods. This was a retrospective analysis of the curative effect of the trans-superior meatus approach for diseases in the sphenoid sinus and sellar area in 138 cases. Results. All of 138 patients had successful operations and no serious complication occurred. All cases were followed up for a period of 1-3 years. No recurrence was found in 94 patients with isolated sphenoid sinus disease (sinusitis, mucoceles, or mycosis). Of 24 patients with pituitary adenoma, 17 patients had entire resection and no recurrence was found. Four patients had subtotal resection and three patients had partial resection with postoperative radiotherapy, and preoperative symptoms were improved. Of 13 cases of cerebrospinal rhinorrhea in the sphenoid sinus, 12 cases were successfully repaired by a single operation and 1 case was successfully repaired by a repeat operation. Among seven cases with decompression of the optic canal, four had obvious effect, two cases showed improvement, and there was no improvement in one case. [ABSTRACT FROM AUTHOR]