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1.
Sensors (Basel) ; 23(5)2023 Feb 28.
Article in English | MEDLINE | ID: mdl-36904864

ABSTRACT

Tactile sensing is important for robots to perceive the world as it captures the physical surface properties of the object with which it is in contact and is robust to illumination and colour variances. However, due to the limited sensing area and the resistance of their fixed surface when they are applied with relative motions to the object, current tactile sensors have to tap the tactile sensor on the target object a great number of times when assessing a large surface, i.e., pressing, lifting up, and shifting to another region. This process is ineffective and time-consuming. It is also undesirable to drag such sensors as this often damages the sensitive membrane of the sensor or the object. To address these problems, we propose a roller-based optical tactile sensor named TouchRoller, which can roll around its centre axis. It maintains being in contact with the assessed surface throughout the entire motion, allowing for efficient and continuous measurement. Extensive experiments showed that the TouchRoller sensor can cover a textured surface of 8 cm × 11 cm in a short time of 10 s, much more effectively than a flat optical tactile sensor (in 196 s). The reconstructed map of the texture from the collected tactile images has a high Structural Similarity Index (SSIM) of 0.31 on average when compared with the visual texture. In addition, the contacts on the sensor can be localised with a low localisation error, 2.63 mm in the centre regions and 7.66 mm on average. The proposed sensor will enable the fast assessment of large surfaces with high-resolution tactile sensing and the effective collection of tactile images.

2.
J Voice ; 35(1): 157.e1-157.e6, 2021 Jan.
Article in English | MEDLINE | ID: mdl-31526666

ABSTRACT

The primary aim of this research was to quantify the degree to which the upper airway temperature changes with singing warm-up. Based on prior upper airway thermoregulation research it was hypothesized that upper airway temperature would not significantly increase during singing warm up when compared to prewarm up and recovery phases. Ten participants completed a short singing warm-up of their choice until they felt sufficiently warmed up while upper airway temperature was measured at 1 second intervals via a transnasal thermistor placed against the posterior pharyngeal wall, just above the larynx. Descriptive statistics and statistical modeling were used for comparison of pre-warm-up, warm-up, and recovery phases of a short singing warm-up. Results indicated a physiologically-significant increase (≥0.5°C) of upper airway temperature during the singing warm-up when compared to the prewarm up average. Significant differences (P < 0.0001) were identified between all pairwise comparisons analyzed for the three phases of data collected (baseline, warm-up, and recovery). These findings support an upper airway tissue temperature increase in response to the singing warm-up. The extent to which these findings can be generalized to the intrinsic laryngeal muscles is still unknown given the technical difficulty of obtaining intramuscular laryngeal temperature measures.


Subject(s)
Singing , Warm-Up Exercise , Body Temperature Regulation , Humans , Laryngeal Muscles , Voice Training
3.
Breast Cancer ; 28(2): 277-288, 2021 Mar.
Article in English | MEDLINE | ID: mdl-32909167

ABSTRACT

INTRODUCTION: The purpose of this study was to examine the impact of preexisting cognitive impairments on survival and medication adherence, and whether chronic medication adherence mediates or moderates the association between cognitive impairments and mortality in patients with breast cancer. METHODS: This retrospective cohort study of older female patients diagnosed with breast cancer was conducted using the Surveillance, Epidemiology, and End Results Medicare Linked Database. We examined the risk of mortality from cancer and non-cancer causes in patients with and without a history of cognitive impairment. In addition, we examined if chronic medication adherence rates differ between these groups of patients and if medication adherence mediates or moderates the association between cognitive impairments and non-cancer mortality. RESULTS: Mortality from cancer-specific (HR 1.13, 95% CI 1.04-1.23) and non-cancer causes (HR 1.16, 95% CI 1.11-1.21) as well as all-cause mortality (HR 1.30, 95% CI 1.23-1.38) was significantly higher in patients with cognitive impairments compared to those without cognitive impairment. Both groups showed low adherence levels to chronic medication before and after the breast cancer diagnosis. Further analysis did not show that medication adherence mediates or moderates the relationship between cognitive impairment and non-cancer mortality (p value > 0.05). CONCLUSION: The results of this study indicate that older female patients with cognitive impairments and a breast cancer diagnosis have a heightened risk of cancer-specific and non-cancer mortality. Our findings do not indicate that chronic medication adherence plays a role in the association between a history of cognitive impairment and mortality, it is still necessary to further investigate this issue.


Subject(s)
Breast Neoplasms/drug therapy , Breast Neoplasms/epidemiology , Cognitive Dysfunction/epidemiology , Medication Adherence/psychology , Aged , Aged, 80 and over , Breast Neoplasms/mortality , Comorbidity , Female , Humans , Incidence , Kaplan-Meier Estimate , Medicare , Retrospective Studies , SEER Program , Survival Rate , Treatment Outcome , United States/epidemiology
4.
Eur Geriatr Med ; 11(6): 1017-1026, 2020 12.
Article in English | MEDLINE | ID: mdl-32572725

ABSTRACT

PURPOSE: This study aimed to evaluate the association between the development of cognitive impairment and the use of antidepressants among older women with breast cancer. METHODS: This retrospective cohort study used the United States National Cancer Institute's Surveillance, Epidemiology, and End Results-Medicare database to identify women who were 67 years old and older and had breast cancer between 2008 and 2013. Propensity scoring was used to account for confounding pre-treatment factors, and Cox proportional hazards modeling was used to examine the risk of developing cognitive impairment among patients based on whether they used antidepressants. RESULTS: A total of 3174 women taking antidepressants (mean age 75.2 ± 6.4) were matched with 3174 women not taking antidepressants (mean age 75.4 ± 6.7). Antidepressant use was associated with a significantly increased risk of cognitive impairment (hazard ratio [HR]: 1.33, 95%; confidence interval [CI]: 1.18-1.48). Additionally, we found that older women without a history of depression or anxiety who use antidepressants have a higher risk of developing cognitive impairment than those who did not use antidepressants (HR: 1.53, 95%; CI: 1.34-1.75 and HR: 1.39, 95%; CI: 1.23-1.56, respectively). Subgroup analysis showed that the use of non-tricyclic antidepressants (TCAs) was associated with a higher risk of cognitive impairment. CONCLUSION: We found that non-TCA antidepressant use in older women with breast cancer was associated with a higher risk of cognitive impairment. This association was also observed among older women without depression or anxiety who used antidepressants.


Subject(s)
Breast Neoplasms , Cognitive Dysfunction , Aged , Antidepressive Agents/adverse effects , Breast Neoplasms/drug therapy , Cognitive Dysfunction/chemically induced , Female , Humans , Medicare , Retrospective Studies , United States/epidemiology
5.
Sci Rep ; 8(1): 13251, 2018 09 05.
Article in English | MEDLINE | ID: mdl-30185933

ABSTRACT

When the subterranean termite Reticulitermes flavipes is fed heat-killed methicillin resistant Staphylococcus aureus (MRSA) or Pseudomonas aeruginosa, the termite produces proteins with antibacterial activity against the inducer pathogen in its hemolymph. We used a proteomic approach to characterize the alterations in protein profiles caused by the inducer bacterium in the hemolymph of the termite. Nano-liquid chromatography-tandem mass spectrometry analysis identified a total of 221 proteins and approximately 70% of these proteins could be associated with biological processes and molecular functions. Challenges with these human pathogens induced a total of 57 proteins (35 in MRSA-challenged, 16 in P. aeruginosa-challenged, and 6 shared by both treatments) and suppressed 13 proteins by both pathogens. Quasi-Poisson likelihood modeling with false discovery rate adjustment identified a total of 18 and 40 proteins that were differentially expressed at least 2.5-fold in response to MRSA and P. aeruginosa-challenge, respectively. We selected 7 differentially expressed proteins and verified their gene expression levels via quantitative real-time RT-PCR. Our findings provide an initial insight into a putative termite immune response against MRSA and P. aeruginosa-challenge.


Subject(s)
Insect Proteins/metabolism , Isoptera/microbiology , Methicillin-Resistant Staphylococcus aureus/pathogenicity , Proteomics/methods , Pseudomonas aeruginosa/pathogenicity , Animals , Chromatography, Liquid , Gene Expression Profiling , Gene Expression Regulation , Hemolymph/metabolism , Hemolymph/microbiology , Immunity, Innate , Insect Proteins/genetics , Isoptera/metabolism , Nanotechnology , Tandem Mass Spectrometry
6.
IEEE Trans Cybern ; 48(9): 2542-2555, 2018 Sep.
Article in English | MEDLINE | ID: mdl-28885168

ABSTRACT

In this paper, the problem of multi-view embedding from different visual cues and modalities is considered. We propose a unified solution for subspace learning methods using the Rayleigh quotient, which is extensible for multiple views, supervised learning, and nonlinear embeddings. Numerous methods including canonical correlation analysis, partial least square regression, and linear discriminant analysis are studied using specific intrinsic and penalty graphs within the same framework. Nonlinear extensions based on kernels and (deep) neural networks are derived, achieving better performance than the linear ones. Moreover, a novel multi-view modular discriminant analysis is proposed by taking the view difference into consideration. We demonstrate the effectiveness of the proposed multi-view embedding methods on visual object recognition and cross-modal image retrieval, and obtain superior results in both applications compared to related methods.

7.
J Speech Lang Hear Res ; 60(7): 1831-1842, 2017 07 12.
Article in English | MEDLINE | ID: mdl-28614843

ABSTRACT

Purpose: Translating exercise-science methodology for determination of muscle bioenergetics, we hypothesized that the temporal voice-use patterns for classroom and music teachers would indicate a reliance on the immediate energy system for laryngeal skeletal-muscle metabolism. It was hypothesized that the music-teacher group would produce longer voiced segments than the classroom teachers. Method: Using a between- and within-group multivariate analysis-of-variance design (5 classroom teachers; 7 music teachers), we analyzed fundamental-frequency data-collected via an ambulatory phonation monitor-for length (seconds) of voiced and nonvoiced intervals. Data were collected for 7.5 hr during the workday, over the course of several workdays for each teacher. Results: Descriptive analyses of voiced and nonvoiced intervals indicated that over 99% of voiced segments for both groups were no longer than 3.15 s, supporting the hypothesis of reliance on the immediate energy system for muscle bioenergetics. Significant differences were identified between and within the classroom- and music-teacher groups, with the music-teacher group producing longer voiced segments overall. Conclusions: Knowledge of probable intrinsic laryngeal skeletal-muscle bioenergetics requirements could inform new interdisciplinary considerations for voice habilitation and rehabilitation.


Subject(s)
School Teachers , Voice , Adult , Energy Metabolism , Female , Humans , Laryngeal Muscles/metabolism , Male , Middle Aged , Multivariate Analysis , Time Factors , Voice/physiology , Voice Training , Young Adult
8.
Biostatistics ; 18(2): 386-401, 2017 04 01.
Article in English | MEDLINE | ID: mdl-28375451

ABSTRACT

Univariate semiparametric methods are often used in modeling nonlinear age trajectories for imaging data, which may result in efficiency loss and lower power for identifying important age-related effects that exist in the data. As observed in multiple neuroimaging studies, age trajectories show similar nonlinear patterns for the left and right corresponding regions and for the different parts of a big organ such as the corpus callosum. To incorporate the spatial similarity information without assuming spatial smoothness, we propose a multivariate semiparametric regression model with a spatial similarity penalty, which constrains the variation of the age trajectories among similar regions. The proposed method is applicable to both cross-sectional and longitudinal region-level imaging data. We show the asymptotic rates for the bias and covariance functions of the proposed estimator and its asymptotic normality. Our simulation studies demonstrate that by borrowing information from similar regions, the proposed spatial similarity method improves the efficiency remarkably. We apply the proposed method to two neuroimaging data examples. The results reveal that accounting for the spatial similarity leads to more accurate estimators and better functional clustering results for visualizing brain atrophy pattern.Functional clustering; Longitudinal magnetic resonance imaging (MRI); Penalized B-splines; Region of interest (ROI); Spatial penalty.


Subject(s)
Data Interpretation, Statistical , Magnetic Resonance Imaging/methods , Neuroimaging/methods , Spatial Analysis , Humans
9.
Front Aging Neurosci ; 8: 176, 2016.
Article in English | MEDLINE | ID: mdl-27486400

ABSTRACT

Neuroimaging studies of cognitive and brain aging often yield massive datasets that create many analytic and statistical challenges. In this paper, we discuss and address several limitations in the existing work. (1) Linear models are often used to model the age effects on neuroimaging markers, which may be inadequate in capturing the potential nonlinear age effects. (2) Marginal correlations are often used in brain network analysis, which are not efficient in characterizing a complex brain network. (3) Due to the challenge of high-dimensionality, only a small subset of the regional neuroimaging markers is considered in a prediction model, which could miss important regional markers. To overcome those obstacles, we introduce several advanced statistical methods for analyzing data from cognitive and brain aging studies. Specifically, we introduce semiparametric models for modeling age effects, graphical models for brain network analysis, and penalized regression methods for selecting the most important markers in predicting cognitive outcomes. We illustrate these methods using the healthy aging data from the Active Brain Study.

10.
Sci Rep ; 6: 27104, 2016 06 02.
Article in English | MEDLINE | ID: mdl-27251306

ABSTRACT

Synthetic oligodeoxynucleotides containing unmethylated CpG dinucleotides (CpG ODN) function as potential radiosensitizers for glioma treatment, although the underlying mechanism is unclear. It was observed that CpG ODN107, when combined with irradiation, did not induce apoptosis. Herein, the effect of CpG ODN107 + irradiation on autophagy and the related signaling pathways was investigated. In vitro, CpG ODN107 + irradiation induced autophagosome formation, increased the ratio of LC3 II/LC3 I, beclin 1 and decreased p62 expression in U87 cells. Meanwhile, CpG ODN107 also increased LC3 II/LC3 I expression in U251 and CHG-5 cells. In vivo, CpG ODN107 combined with local radiotherapy induced autophagosome formation in orthotopic transplantation tumor. Investigation of the molecular mechanisms demonstrated that CpG ODN107 + irradiation increased the levels of TLR9 and p-ERK, and decreased the level of p-mTOR in glioma cells. Further, TLR9-specific siRNA could affect the expressions of p-ERK and autophagy-related proteins in glioma cells. Taken together, CpG ODN107 combined with irradiation could induce autophagic cell death, and this effect was closely related to the TLR9-ERK-mTOR signaling pathway in glioma cells, providing new insights into the investigation mechanism of CpG ODN.


Subject(s)
Autophagy , Brain Neoplasms/radiotherapy , Glioma/radiotherapy , MAP Kinase Signaling System , Oligodeoxyribonucleotides/pharmacology , Radiation-Sensitizing Agents/pharmacology , Animals , Cell Line, Tumor , Cell Survival , Extracellular Signal-Regulated MAP Kinases/metabolism , Gene Expression , Gene Knockdown Techniques , Humans , Mice, Nude , TOR Serine-Threonine Kinases/metabolism , Toll-Like Receptor 9/genetics , Toll-Like Receptor 9/metabolism , Xenograft Model Antitumor Assays
11.
Stat Med ; 33(12): 2103-14, 2014 May 30.
Article in English | MEDLINE | ID: mdl-24488881

ABSTRACT

We propose a score-type statistic to evaluate heterogeneity in zero-inflated models for count data in a stratified population, where heterogeneity is defined as instances in which the zero counts are generated from two sources. Evaluating heterogeneity in this class of models has attracted considerable attention in the literature, but existing testing procedures have primarily relied on the constancy assumption under the alternative hypothesis. In this paper, we extend the literature by describing a score-type test to evaluate homogeneity against general alternatives that do not neglect the stratification information under the alternative hypothesis. The limiting null distribution of the proposed test statistic is a mixture of chi-squared distributions that can be well approximated by a simple parametric bootstrap procedure. Our numerical simulation studies show that the proposed test can greatly improve efficiency over tests of heterogeneity that ignore the stratification information. An empirical application to dental caries data in early childhood further shows the importance and practical utility of the methodology in using the stratification profile to detect heterogeneity in the population.


Subject(s)
Dental Caries/ethnology , Models, Statistical , Black or African American , Child, Preschool , Humans , Infant , Michigan/epidemiology , Oral Health , Poisson Distribution
12.
Scand Stat Theory Appl ; 40(2): 256-273, 2013 Jun 01.
Article in English | MEDLINE | ID: mdl-23788826

ABSTRACT

Many statistical models arising in applications contain non- and weakly-identified parameters. Due to identifiability concerns, tests concerning the parameters of interest may not be able to use conventional theories and it may not be clear how to assess statistical significance. This paper extends the literature by developing a testing procedure that can be used to evaluate hypotheses under non- and weakly-identifiable semiparametric models. The test statistic is constructed from a general estimating function of a finite dimensional parameter model representing the population characteristics of interest, but other characteristics which may be described by infinite dimensional parameters, and viewed as nuisance, are left completely unspecified. We derive the limiting distribution of this statistic and propose theoretically justified resampling approaches to approximate its asymptotic distribution. The methodology's practical utility is illustrated in simulations and an analysis of quality-of-life outcomes from a longitudinal study on breast cancer.

13.
Int Immunopharmacol ; 17(2): 237-44, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23791618

ABSTRACT

Malignant glioma displays invasive growth and is difficult to be completely excised; surgery combined with subsequent radiotherapy is a standard treatment for patients. CpG oligodeoxynucleotides (CpG ODN) can enhance radiotherapeutic effect in some tumors. Angiogenesis is crucial for tumor progression and metastasis. Anti-angiogenic strategy thus may be effective for tumor treatment. Herein, the antiangiogenic activity and radiosensitizing effect of CpG ODN107 on glioma were investigated. Our results showed that the growth of glioma cell line U87 was significantly inhibited by CpG ODN107 (10µg/ml) in combination with irradiation (5Gy) in vitro. In orthotopic implantation model of nude mice, the survival rate of mice significantly increased after treatment with CpG ODN107 (0.083mg/kg) in combination with radiotherapy (10Gy) as compared with treatment with local radiotherapy alone. CpG ODN107 in combination with radiotherapy significantly decreased microvessel density (MVD), VEGF level and HIF-1α expression in orthotopic implantation glioma. In conclusion, CpG ODN107 significantly increased the radiosensitivity of U87 human glioma cells in vitro and in vivo. The radiosensitizing effect of CpG ODN 107 is tightly related to its anti-angiogenic activity via suppression of HIF-1α/VEGF pathway.


Subject(s)
Angiogenesis Inhibitors/administration & dosage , Brain Neoplasms/drug therapy , Glioma/drug therapy , Microvessels/drug effects , Neovascularization, Pathologic/drug therapy , Oligodeoxyribonucleotides/administration & dosage , Radiation-Sensitizing Agents/administration & dosage , Angiogenesis Inhibitors/pharmacology , Animals , Brain Neoplasms/blood supply , Brain Neoplasms/radiotherapy , Cell Growth Processes/drug effects , Cell Line, Tumor , Chemotherapy, Adjuvant , Combined Modality Therapy , Glioma/blood supply , Glioma/radiotherapy , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Mice, Nude , Microvessels/pathology , Neoplasm Transplantation , Neovascularization, Pathologic/radiotherapy , Oligodeoxyribonucleotides/pharmacology , Radiation-Sensitizing Agents/pharmacology , Vascular Endothelial Growth Factor A/metabolism , Xenograft Model Antitumor Assays
14.
Tumour Biol ; 33(5): 1607-18, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22739939

ABSTRACT

Radiotherapy is a standard treatment for glioma patient with or without surgery; radiosensitizer can increase tumor sensitivity for radiotherapy. Herein, a synthetic oligodeoxynucleotide containing unmethylated CpG dinucleotides (CpG ODN107) as a radiosensitizer was investigated in vitro and in vivo, and the possible mechanisms were studied in vitro. In the present experiments, the human glioma U87 cell line used herein was resistant to 5 Gy of ß-ray irradiation. The results showed that 10 µg/ml of CpG ODN107 in combination with irradiation significantly inhibited cell proliferation both in MTT assay and colony formation experiments. Tumor growth was inhibited by CpG ODN107 in combination with local irradiation but not by local irradiation or CpG ODN107 alone in human glioma xenograft model in nude mice. The inhibition ratio of tumor growth produced by CpG ODN107 (1.7, 5, and 15 mg/kg) in combination with irradiation was 27.3, 67.0, and 65.5 %, respectively. Further molecular mechanisms were studied in vitro. The results showed that the expressions of iNOS, NO, TLR9 mRNA, and NF-κB p50/p65 increased in the cells treated with CpG ODN107 in combination with irradiation. CpG ODN107 in combination with irradiation did not induce apoptosis but induced cell cycle arrest at G(1) phase. The said results demonstrated that CpG ODN107 possessed a radiosensitizing effect via TLR9-mediated NF-κB activation and NO production in the tumor cells, leading to cell cycle arrest. Therefore, CpG ODN107 is a potential candidate as radiosensitizer for human glioma.


Subject(s)
Brain Neoplasms/metabolism , Glioma/metabolism , NF-kappa B/metabolism , Nitric Oxide/biosynthesis , Oligodeoxyribonucleotides/pharmacology , Radiation-Sensitizing Agents/pharmacology , Toll-Like Receptor 9/metabolism , Animals , Apoptosis/drug effects , Apoptosis/radiation effects , Brain Neoplasms/genetics , Cell Cycle Checkpoints/drug effects , Cell Cycle Checkpoints/radiation effects , Cell Line, Tumor , Cell Proliferation/drug effects , Enzyme Activation/drug effects , Enzyme Activation/radiation effects , Gene Expression Regulation, Neoplastic/drug effects , Gene Expression Regulation, Neoplastic/radiation effects , Glioma/genetics , Humans , Male , Mice , Mice, Nude , Nitric Oxide Synthase Type II/metabolism , Oligodeoxyribonucleotides/administration & dosage , Radiation-Sensitizing Agents/administration & dosage , Toll-Like Receptor 9/genetics , Tumor Burden/drug effects , Tumor Burden/radiation effects , Xenograft Model Antitumor Assays
15.
J Nonparametr Stat ; 24(2): 359-377, 2012 Jun 01.
Article in English | MEDLINE | ID: mdl-22665964

ABSTRACT

A polynomial spline estimator is proposed for the mean function of dense functional data together with a simultaneous confidence band which is asymptotically correct. In addition, the spline estimator and its accompanying confidence band enjoy oracle efficiency in the sense that they are asymptotically the same as if all random trajectories are observed entirely and without errors. The confidence band is also extended to the difference of mean functions of two populations of functional data. Simulation experiments provide strong evidence that corroborates the asymptotic theory while computing is efficient. The confidence band procedure is illustrated by analyzing the near infrared spectroscopy data.

16.
J Stat Plan Inference ; 142(6): 1557-1570, 2012 Jun 01.
Article in English | MEDLINE | ID: mdl-22423174

ABSTRACT

We develop in this paper a new procedure to construct simultaneous confidence bands for derivatives of mean curves in functional data analysis. The technique involves polynomial splines that provide an approximation to the derivatives of the mean functions, the covariance functions and the associated eigenfunctions. We show that the proposed procedure has desirable statistical properties. In particular, we first show that the proposed estimators of derivatives of the mean curves are semiparametrically efficient. Second, we establish consistency results for derivatives of covariance functions and their eigenfunctions. Most importantly, we show that the proposed spline confidence bands are asymptotically efficient as if all random trajectories were observed with no error. Finally, the confidence band procedure is illustrated through numerical simulation studies and a real life example.

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