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Nevin Manimala Statistics

Comparing adaptive fractal and detrended fluctuation analyses of stride time variability: Tests of equivalence

Gait Posture. 2022 Feb 17;94:9-14. doi: 10.1016/j.gaitpost.2022.02.019. Online ahead of print.

ABSTRACT

BACKGROUND: Fractal analyses quantify self-similarities in stride-to-stride fluctuations over different time scales. Fractal exponents can be measured with adaptive fractal analysis (AFA) or detrended fluctuation analysis (DFA), though measurements obtained with the algorithms have not been directly compared.

RESEARCH QUESTION: Are stride time fractal exponents measured with AFA and DFA algorithms equivalent?

METHODS: Data from 50 participants with Parkinson’s Disease (n = 15), age-similar healthy adults (n = 15) and healthy young adults (n = 20) were analyzed in this cross-sectional, observational study. Participants completed 6-min walks at self-selected speeds overground on a straight walkway and on a treadmill. Stride times were measured with inertial measurement units. Fractal exponents in stride time data were processed using AFA and DFA algorithms and compared with two one-sided tests of equivalence. Mixed ANOVAs were used to compare exponents between groups and conditions.

RESULTS: Fractal exponents computed with AFA and DFA were equivalent neither in the overground (0.796 & 0.830, respectively, p = .587) nor treadmill conditions (0.806 & 0.882, respectively, p = .122). Fractal exponents measured with DFA were higher than when measured with AFA. Standard errors were 22% lower when measured with AFA. Additionally, a group × condition interaction was statistically significant when fractal exponents were processed with the AFA algorithm (F(2,47) = 11.696, p < .001), whereas the group × condition interaction was not statistically significant when DFA exponents were compared (F(2, 47) = 2.144, p = .129).

SIGNIFICANCE: AFA and DFA do not produce equivalent estimates of the fractal exponent α in stride time dynamics. Estimates of the fractal exponent α obtained with AFA or DFA algorithms therefore should not be used interchangeably. Standard errors were lower when derived with AFA. Fractal exponents calculated with AFA may be more sensitive to conditions that influence stride time fractal dynamics than are measures calculated with DFA.

PMID:35189574 | DOI:10.1016/j.gaitpost.2022.02.019

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Nevin Manimala Statistics

Effects of a tongue training program in Parkinson’s disease: Analysis of electrical activity and strength of suprahyoid muscles

J Electromyogr Kinesiol. 2022 Feb 12;63:102642. doi: 10.1016/j.jelekin.2022.102642. Online ahead of print.

ABSTRACT

OBJECTIVE: To assess the electrical activity of the suprahyoid muscle and the tongue pressure in a two-wing program of tongue strengthening in individuals with Parkinson’s disease (PD).

METHODS: A pre-post-detraining design study included sixty PD patients assigned to two groups randomly. The experimental group (EG) performed tongue isometric pressure exercises using the Iowa Oral Performance Instrument with an increasing scheme of 5% load weekly and traditional tongue therapy for 8 weeks. The control group (CG) performed only traditional therapy. The electrical activity of suprahyoids was measured using surface electromyography (sEMG) during tongue-to-palate pressure. Four selected domains of the Swallowing Quality of Life Questionnaire (SWAL-QOL) mostly related to tongue strength were considered.

RESULTS: The experimental group showed increased sEMG values of suprahyoid muscles reaching statistically significant difference at the fourth week of tongue training, while the control did it at the eighth week. Experimental group showed significant improvements in tongue strength (d = 2.128; p = 0.000). Only controls showed detraining effect. Statistically significant difference within groups were found in one and three dimensions of the SWAL-QOL in the CG and EG, respectively.

CONCLUSION: Analysis of electrical activity on suprahyoids muscles provided a better understanding of the changes underlying the outcomes of tongue strength gains obtained through a combined tongue strengthening exercises protocol in PD. Such protocol led not only to increased tongue strength but also to a better perceived swallowing function in PD subjects.

PMID:35189571 | DOI:10.1016/j.jelekin.2022.102642

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Nevin Manimala Statistics

45Ti targeted tracers for PET imaging of PSMA

Nucl Med Biol. 2022 Feb 4;108-109:16-23. doi: 10.1016/j.nucmedbio.2022.01.005. Online ahead of print.

ABSTRACT

PURPOSE: Positron Emission Tomography is an important molecular imaging technique for detection and diagnoses of various disease states. This work aims to develop novel titanium-45 (t½ = 3.08 h) PET tracers using Prostate Specific Membrane Antigen (PSMA) targeting vectors for imaging of prostate cancer as proof of concept for this relatively unexplored isotope.

PROCEDURES: Titanium-45 was produced on the University of Alabama at Birmingham (UAB) TR24 cyclotron using proton bombardments on natural scandium foils and separated using procedures described previously [1]. After purification, Titanium-45 was used to radiolabel two PSMA-targeting molecules; DFO-DUPA and LDFC-DUPA. Radiochemical yields were determined via radio-high purity liquid chromatography (radioHPLC). The radiolabeled compounds were tested both in vitro and in vivo using PSMA+ cell lines (LNCaP and 22Rv1) and PSMA- cell lines (PC3).

RESULTS: Titanium-45 was produced and purified in yields suitable for research studies. Radiochemical yields of up to 98 ± 1% were achieved with DFO-DUPA and 92 ± 7% with LDFC-DUPA. PSMA specific targeting was observed in vitro in PSMA positive cells (LNCaP (0.6% ± 0.05%) and confirmed by blocking (0.15% ± 0.04%) (P < 0.0001)), compared to uptake in the PSMA negative cells (PC3 (0.07% ± 0.008%)) and confirmed by blocking (0.07% ± 0.01%) (P = 0.5253). In vivo studies demonstrated statistically significant uptake in LNCaP tumors (2.3% ± 0.3% ID/g) compared to PC3 tumor uptake (0.1% ± 0.07%).

CONCLUSIONS: This work shows that titanium-45 can be used to radiolabel PSMA targeting compounds with high radiochemical yields. These radiolabeled compounds remain intact in serum for at least two half-lives of titanium-45, showing that these compounds would be appropriate for implementation in the clinical setting. This study shows the feasibility of using titanium-45 as positron emitting radiometal for use in imaging PSMA+ prostate cancer, and illustrates that further research is in this area is warranted.

PMID:35189565 | DOI:10.1016/j.nucmedbio.2022.01.005

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Nevin Manimala Statistics

Impacts of hydrological alteration on ecosystem services changes of a large river-connected lake (Poyang Lake), China

J Environ Manage. 2022 Feb 18;310:114750. doi: 10.1016/j.jenvman.2022.114750. Online ahead of print.

ABSTRACT

Large lakes provide various types of ecosystem services (ESs), of which stocks and variations induced by hydrological alterations are largely unquantified. The present study investigates the long-term changes of five key ESs (i.e., flood regulation, water supply, fish production, nutrient retention and biodiversity conservation) in a large river connected lake (Poyang Lake), with special attention to impacts of hydrological alteration induced by the Three Gorges Dam (TGD). Hydrological data series, hydrodynamic model, the nutrient balance, fishery statistics, and wetland winter waterbird survey data from 1980 to 2016 were employed. Results showed that Poyang Lake provide significant ESs, with long-term average flood regulation, water supply and nutrient retention services of 167.7 × 108 m3, 31.53 × 108 m3, and 15.12% of total phosphorus load, respectively. The fish production service ranged from 1.74 × 104t to 7.19 × 104t, with an average value of 3.12 × 104t. All five key ESs exhibited a downward trend since the 2000s, especially for water supply, fish production and nutrient retention services (p < 0.05), which might be largely attributed to the hydrological condition changes induced by TGD operation. Nevertheless, more detailed monitoring data and biophysical models are required to further acknowledge the changes in biodiversity conservation and fish production services and their linkages with the TGD. The present study sheds light on long-term ES changes in large lakes and their possible linkages with human influences through hydropower projects.

PMID:35189555 | DOI:10.1016/j.jenvman.2022.114750

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Nevin Manimala Statistics

High frame rate multi-perspective cardiac ultrasound imaging using phased array probes

Ultrasonics. 2022 Feb 5;123:106701. doi: 10.1016/j.ultras.2022.106701. Online ahead of print.

ABSTRACT

Ultrasound (US) imaging is used to assess cardiac disease by assessing the geometry and function of the heart utilizing its high spatial and temporal resolution. However, because of physical constraints, drawbacks of US include limited field-of-view, refraction, resolution and contrast anisotropy. These issues cannot be resolved when using a single probe. Here, an interleaved multi-perspective 2-D US imaging system was introduced, aiming at improved imaging of the left ventricle (LV) of the heart by acquiring US data from two separate phased array probes simultaneously at a high frame rate. In an ex-vivo experiment of a beating porcine heart, parasternal long-axis and apical views of the left ventricle were acquired using two phased array probes. Interleaved multi-probe US data were acquired at a frame rate of 170 frames per second (FPS) using diverging wave imaging under 11 angles. Image registration and fusion algorithms were developed to align and fuse the US images from two different probes. First- and second-order speckle statistics were computed to characterize the resulting probability distribution function and point spread function of the multi-probe image data. First-order speckle analysis showed less overlap of the histograms (reduction of 34.4%) and higher contrast-to-noise ratio (CNR, increase of 27.3%) between endocardium and myocardium in the fused images. Autocorrelation results showed an improved and more isotropic resolution for the multi-perspective images (single-perspective: 0.59 mm × 0.21 mm, multi-perspective: 0.35 mm × 0.18 mm). Moreover, mean gradient (MG) (increase of 74.4%) and entropy (increase of 23.1%) results indicated that image details of the myocardial tissue can be better observed after fusion. To conclude, interleaved multi-perspective high frame rate US imaging was developed and demonstrated in an ex-vivo experimental setup, revealing enlarged field-of-view, and improved image contrast and resolution of cardiac images.

PMID:35189524 | DOI:10.1016/j.ultras.2022.106701

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Nevin Manimala Statistics

Racial disparities in the cost of inpatient spinal cord stimulator surgery among patients in the 2016-2018 National Inpatient Sample

J Clin Neurosci. 2022 Feb 18;98:189-193. doi: 10.1016/j.jocn.2022.02.019. Online ahead of print.

ABSTRACT

INTRODUCTION: Spinal cord stimulation is a promising therapy for patients with treatment refractory pain syndromes, and a viable alternative to chronic opioid therapy. Racial disparities are well-documented in the field of pain medicine. This study seeks to determine whether racial disparities are present in spinal cord stimulator (SCS) surgery involving inpatient hospital stays in the United States.

OBJECTIVE: The objective of this study was to analyze the effects of race on health care cost and utilization for patients receiving inpatient SCS surgery. We used total charges incurred by the patient to measure cost and length of stay (LOS) to measures hospital utilization for patients undergoing inpatient SCS surgery. We examined cost and utilization for inpatient surgeries involving SCS insertion, removal, and revision across different race demographics.

METHODS: This retrospective cohort study used ICD-10 procedure codes to query for all patients in the 2016-2018 National Inpatient Sample (NIS) who received SCS insertion, removal, and revision surgeries. Univariate analysis was performed in R-studio to assess the relationship between race, LOS, and total charge. Multivariate analysis was also performed in R-studio to adjust for possible confounders.

RESULTS: Hispanic race was associated with higher total charge for inpatient SCS surgery (β=+0.29, p = 3.92e-07). Hospital region was also associated with total charge. The South (β=+0.12, p = 3.7e-03) and the West (β=+0.28, p = 3.8e-09) were associated with higher total charge. The linear model also showed that patients with more comorbidities and complex cases paid higher total charges (β=+0.014, p = 6.2e-04). There was no statistically significant difference in LOS between race demographics.

CONCLUSION: After adjusting for age, gender, type of surgical approach (percutaneous vs. open), household income, insurance coverage, hospital region, and hospital location (urban vs. rural vs. teaching), and comorbidity scores, Hispanic patients had higher total charges for inpatient SCS surgery, but there was no disparity in total charge between white and black patients. White patients were older than minority patients at the time of inpatient SCS surgery.

PMID:35189543 | DOI:10.1016/j.jocn.2022.02.019

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Nevin Manimala Statistics

Citizen science projects in freshwater monitoring. From individual design to clusters?

J Environ Manage. 2022 Feb 18;309:114714. doi: 10.1016/j.jenvman.2022.114714. Online ahead of print.

ABSTRACT

Citizen science projects spring up in freshwater monitoring, with an increasing number of projects in river, lake, and groundwater monitoring around the globe. Citizen science scholars assume that these projects have different designs, including diverse characteristics of citizens, institutions, and forms of interactions, potentially affecting the outcomes of these projects. Given the strong focus on case studies or reviews in the field, there is, however, little comparative evidence of the different types of citizen science projects in freshwater monitoring. Based on a global survey, this study provides a systematic comparative analysis of the design of 85 citizen science projects in the field of freshwater monitoring. Descriptive statistics reveal how projects differ along 45 literature-based design variables raised in the survey. Factor analysis based on 31 of these variables yields ten key design factors, and cluster analysis, based on these design factors, allows to identify seven distinguished clusters of citizen science projects. While these clusters are rather heterogeneous, they reveal differences between groups of projects regarding institutional motivation, citizen characteristics, and interaction forms. These results significantly add to a systematic comparison of citizen science projects in freshwater monitoring and enable a more effective involvement of citizens in environmental management.

PMID:35189514 | DOI:10.1016/j.jenvman.2022.114714

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Nevin Manimala Statistics

Cognitive frailty among community-dwelling rural elderly population of West Bengal in India

Asian J Psychiatr. 2022 Feb 15;70:103025. doi: 10.1016/j.ajp.2022.103025. Online ahead of print.

ABSTRACT

OBJECTIVES: There has been growing interest in the links between physical frailty and cognitive impairment: both can increase the risk of emerging life-threatening health problems and are currently prominent within the global geriatric health agenda. A recent consensus proposes the idea of ‘cognitive frailty’ defined by the presence of both physical frailty and cognitive impairment in the absence of dementia. Present study is intended to determine the prevalence of cognitive frailty and its associated factors.

METHODS: Cross-sectional survey was conducted among the rural community-dwelling elderly population of West Bengal, India (n = 510), without diagnosed dementia at baseline. An Interview-based questionnaire was administered to obtain information on sociodemographic, physical and psychosocial characteristics. Study participants were categorized as non-cognitive impairment (NCI) and cognitive impairment (CI) by Bangla Adaptation of Mini-Mental State Exam (BMSE ≤ 25) scale, as non-physical frailty (NPF) and physical frailty (PF) using Modified Fried Frailty Phenotype (FP ≥ 3) scale, as robust (NPF + NCI), pre-cognitive frailty (NPF + CI or PF + NCI) and cognitive frailty (PF + CI).

RESULTS: The overall prevalence of cognitive frailty was 21.8%. In multinomial regression analysis, final model indicated that increasing age, being woman, out-of-wedlock, poor education and non-working sociodemographic status had significant association with cognitive frailty. Poor nutritional status, low health-related quality of life and depression are also prone among the cognitively frail participants.

CONCLUSIONS: Present study allows us to understand complementary relationships between sociodemographic, physical, psychosocial characteristics and cognitive frailty. There is a dire need for multidimensional approach for providing appropriate and comprehensive geriatric health care for developing countries like India.

PMID:35189474 | DOI:10.1016/j.ajp.2022.103025

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Nevin Manimala Statistics

Validation of the Danish Comorbidity Index for Acute Myocardial Infarction for predicting one-year mortality in patients with venous thromboembolism

Thromb Res. 2022 Feb 17;212:9-18. doi: 10.1016/j.thromres.2022.02.013. Online ahead of print.

ABSTRACT

INTRODUCTION: The Danish Comorbidity Index for Acute Myocardial Infarction (DANCAMI) was developed to predict one-year mortality after myocardial infarction. We validated DANCAMI in predicting one-year mortality after venous thromboembolism (VTE).

MATERIALS AND METHODS: We identified all first-time VTE patients in Denmark during 2000-2015. Using Cox regression, we assessed the performance of DANCAMI to predict one-year all-cause mortality using Nagelkerke’s R2, Harrell’s C-Statistic, the net reclassification index (NRI), and the integrated discrimination improvement (IDI). We compared the performance of DANCAMI with the Charlson Comorbidity Index (CCI) and the Elixhauser Comorbidity Index (ECI) and evaluated whether DANCAMI comorbidities not included in the CCI predicted one-year mortality. We stratified the analyses by type (deep vein thrombosis [DVT] and pulmonary embolism [PE]) and presence of provoking risk factors.

RESULTS: We identified 108,824 VTE patients of whom 20,649 (19%) died within one year. The R2, C-Statistic, NRI, and IDI for DANCAMI were 0.35, 0.76, 0.63, and 0.098 for VTE overall; 0.43, 0.80, 0.70, and 0.105 for DVT; and 0.24, 0.71, 0.54, and 0.083 for PE. The R2 and C-Statistic for VTE overall were 0.35 and 0.76 for CCI and 0.33 and 0.75 for ECI. After adjusting for age, sex, and all CCI comorbidities, seven DANCAMI comorbidities, not included in the CCI, predicted increased mortality. DANCAMI performed better than the CCI and ECI in predicting mortality after provoked VTE, including provoked DVT and PE.

CONCLUSION: DANCAMI performed comparable to existing comorbidity indices in predicting one-year mortality after first-time VTE overall, but better after provoked VTE.

PMID:35189486 | DOI:10.1016/j.thromres.2022.02.013

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Nevin Manimala Statistics

Are children with unilateral hearing loss more tired?

Int J Pediatr Otorhinolaryngol. 2022 Feb 16;155:111075. doi: 10.1016/j.ijporl.2022.111075. Online ahead of print.

ABSTRACT

OBJECTIVE: To determine whether children with unilateral sensorineural hearing loss (USNHL) and unilateral conductive hearing loss (UCHL) have higher levels of fatigue than literature reported normal hearing (LRNH) children.

METHODS: This was a cross-sectional survey utilizing the PedsQL™ Multidimensional Fatigue Scale administered to children with unilateral hearing loss (UHL) and their parents at two tertiary care academic medical centers and a nationwide microtia/atresia conference. The PedsQL™ Multidimensional Fatigue Scale was used to compare child and parental proxy reports of fatigue among USNHL, UCHL, and LRNH children. ANOVA and post-hoc Tukey Honest Significant Difference testing were used for statistical analysis.

RESULTS: Of 69 children included in the study, 42 had UCHL (61%) and 27 (39%) had USNHL. Children with USNHL reported more total fatigue (mean 69.1, SD 19.3) than LRNH children (mean 80.5, SD 13.3; difference -11.4; 95% CI: -19.98 to -2.84) and children with UCHL (mean 78.0, SD 14.5; difference -8.95; 95% CI: -17.86 to 0.04). Children with UCHL reported similar levels of fatigue compared to LRNH children (difference -2.5; 95% CI: -9.95 to 5.03). Parents of children with USNHL reported greater levels of fatigue (mean 67.6, SD 22.6) in their children than parents of LRNH children (mean 89.6, SD 11.4; difference -22.0; 95% CI: -29.8 to -14.3) and parents of children with UCHL (mean 76.2, SD 17.3; difference -8.6; 95% CI: -17.5 to 0.21). Parents of children with UCHL also report higher levels of fatigue than parents of LRNH children (difference -13.4; 95% CI: -19.98 to -6.84).

CONCLUSIONS: Children with USNHL reported greater levels of fatigue than LRNH children and children with UCHL. Results implicate cognitive load as an important consideration in children with hearing loss. The measurement of fatigue may be a useful indicator to determine the benefit of intervention (e.g., amplification) for these children.

PMID:35189448 | DOI:10.1016/j.ijporl.2022.111075