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Nevin Manimala Statistics

Revisiting seasonal dynamics of total nitrogen in reservoirs with a systematic framework for mining data from existing publications

Water Res. 2021 Jun 21;201:117380. doi: 10.1016/j.watres.2021.117380. Online ahead of print.

ABSTRACT

Investigation of seasonal variations of water quality parameters is essential for understanding the mechanisms of structural changes in aquatic ecosystems and their pollution control. Despite the ongoing rise in scientific production on spatiotemporal distribution characteristics of water quality parameters, such as total nitrogen (TN) in reservoirs, attempts to use published data and incorporate them into a large-scale comparison and trends analyses are lacking. Here, we propose a framework of Data extraction, Data grouping and Statistical analysis (DDS) and illustrate application of this DDS framework with the example of TN in reservoirs. Among 1722 publications related to TN in reservoirs, 58 TN time-series data from 19 reservoirs met the analysis requirements and were extracted using the DDS framework. We performed statistical analysis on these time-series data using Dynamic Time Warping (DTW) combined with agglomerative hierarchical clustering as well as Generalized Additive Models for Location, Scale, and Shape (GAMLSS). Three patterns of seasonal TN dynamics were identified. In Pattern V-Sum, TN concentrations change in a “V” shape, dropping to its lowest value in summer; in Pattern P-Sum, TN increases in late summer/early fall before decreasing again; and in Pattern P-Spr, TN peaks in spring. Identified patterns were driven by phytoplankton growth and precipitation (Pattern V-Sum), nitrate wet deposition and agricultural runoff (Pattern P-Sum), and anthropogenic discharges (Pattern P-Spr). Application of the DDS framework has identified a key bottleneck in assessing the dynamics of TN – low data accessibility and availability. Providing an easily accessible data sharing platform and increasing the accessibility and availability of raw data for research will facilitate improvements and expand the applicability of the DDS framework. Identification of additional spatiotemporal patterns of water quality parameters can provide new insights for more comprehensive pollution control and management of aquatic ecosystems.

PMID:34198201 | DOI:10.1016/j.watres.2021.117380

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Nevin Manimala Statistics

A critical overview of adsorption kinetics for cooling and refrigeration systems

Adv Colloid Interface Sci. 2021 Jun 17;294:102468. doi: 10.1016/j.cis.2021.102468. Online ahead of print.

ABSTRACT

The dynamic uptake of adsorbate onto the porous adsorbent plays a crucial role in determining the performance of the adsorption-based cooling system. Therefore, it is imperative to know the kinetics parameters of an adsorbate – adsorbent pair to design a system to be operated at variable working conditions. The kinetics models of adsorption, used to simulate the adsorption rate of different pairs, are derived and presented in this paper. Besides, the limitations and advantages of the models are also mentioned. Moreover, the dynamic performance of different adsorption pairs is analyzed, and the values of kinetics parameters, determined through experimental procedures and fitting of kinetics models, are also summarized. It is opined that during the initial unsaturated condition of adsorption, the semi-infinite model can be preferred to determine the diffusion time constant. The modification of different models, e.g., Langmuir and linear driving force models, can significantly overcome the drawbacks of the models, as shown by several researchers. However, research may be carried out to investigate different models’ fitting errors from a statistical perspective. Furthermore, to evaluate the dynamic performance of different adsorbates, a lot of research needs to be done, specifically, on the adsorption of the newly developed environment-friendly refrigerants, onto the promising composite adsorbents possessing high thermal conductivity and significantly improved adsorption uptakes.

PMID:34198212 | DOI:10.1016/j.cis.2021.102468

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Nevin Manimala Statistics

Safety of focused ultrasound neuromodulation in humans with temporal lobe epilepsy

Brain Stimul. 2021 Jun 23;14(4):1022-1031. doi: 10.1016/j.brs.2021.06.003. Online ahead of print.

ABSTRACT

OBJECTIVE: Transcranial Focused Ultrasound (tFUS) is a promising new potential neuromodulation tool. However, the safety of tFUS neuromodulation has not yet been assessed adequately. Patients with refractory temporal lobe epilepsy electing to undergo an anterior temporal lobe resection present a unique opportunity to evaluate the safety and efficacy of tFUS neuromodulation. Histological changes in tissue after tFUS can be examined after surgical resection, while further potential safety concerns can be assessed using neuropsychological testing.

METHODS: Neuropsychological functions were assessed in eight patients before and after focused ultrasound sonication of the temporal lobe at intensities up to 5760 mW/cm2. Using the BrainSonix Pulsar 1002, tFUS was delivered under MR guidance, using the Siemens Magnetom 3T Prisma scanner. Neuropsychological changes were assessed using various batteries. Histological changes were assessed using hematoxylin and eosin staining, among others.

RESULTS: With respect to safety, the histological analysis did not reveal any detectable damage to the tissue, except for one subject for whom the histology findings were inconclusive. In addition, neuropsychological testing did not show any statistically significant changes in any test, except for a slight decrease in performance on one of the tests after tFUS.

SIGNIFICANCE: This study supports the hypothesis that low-intensity Transcranial Focused Ultrasound (tFUS) used for neuromodulation of brain circuits at intensities up to 5760 mW/cm2 may be safe for use in human research. However, due to methodological limitations in this study and inconclusive findings, more work is warranted to establish the safety. Future directions include greater number of sonications as well as longer exposure at higher intensity levels to further assess the safety of tFUS for modulation of neuronal circuits.

PMID:34198105 | DOI:10.1016/j.brs.2021.06.003

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Nevin Manimala Statistics

Outcome measures used in psoriatic arthritis registries and cohorts: A systematic literature review of 27 registries or 16,183 patients

Semin Arthritis Rheum. 2021 Jun 20;51(4):888-894. doi: 10.1016/j.semarthrit.2021.06.008. Online ahead of print.

ABSTRACT

INTRODUCTION: Psoriatic arthritis (PsA) is a multidimensional inflammatory disease for which multiple outcome measures can be used to assess disease activity. In 2006, the OMERACT has proposed the first core domain set in PsA. Since 2006, much work has been performed on outcome measures in PsA.

OBJECTIVES: The purpose of this study was to assess outcome measures collected in recent PsA registries or longitudinal cohorts.

METHODS: A systematic literature review was performed in Pubmed Medline (PROSPERO CRD42020175745) to identify all articles reporting on either registries or longitudinal cohorts in PsA, published between 2010 and March 2020. Registries centered on drugs or not PsA-specific, trials and long-term extension studies were excluded. The data collection comprised patient characteristics and the clinical outcome measures reported, including composite scores and patient reported outcomes (PROs). Statistics were descriptive.

RESULTS: Of 673 articles, 73 were analysed, reporting on 27 registries/cohorts. Overall, 16,183 patients were included, with a mean of 599 per study; 51% were men, weighted mean age was 49.7 ± 9.3 years and weighted mean disease duration was 6.8 ± 0.2 years. Overall, 58 different outcome measures were collected. Disease activity composite scores were used in 20/27 (74%) registries through 8 different scores (most frequently Minimal Disease Activity: 41%, DAS28: 33% and DAPSA: 30%). Among the domains of PsA, joint involvement was reported in 26/27 (96%) registries (through the 66/68 joint count: 85%) and skin psoriasis in 93% (through PASI: 72%), whereas enthesitis, dactylitis and axial involvement were less often reported (respectively, 77%, 74% and 52%). Furthermore, 22/27 (82%) studies reported HAQ; the other frequently reported PROs were patient global assessment (70%) and pain (63%).

CONCLUSIONS: Data collection in PsA is very heterogeneous, reflecting the need for international consensus on outcome measures.

PMID:34198147 | DOI:10.1016/j.semarthrit.2021.06.008

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Nevin Manimala Statistics

Auditory brainstem response with click and CE-Chirp® Level Specific stimuli in hearing infants

Int J Pediatr Otorhinolaryngol. 2021 Jun 26;147:110819. doi: 10.1016/j.ijporl.2021.110819. Online ahead of print.

ABSTRACT

INTRODUCTION: The assessment of the integrity of the neural responses with ABR, aims to assist in the differential diagnosis of retrocochlear alterations. The gold standard stimulus for this assessment is Click. However, the CE-Chirp® Level Specific was developed to optimize the triggering of neural responses.

OBJECTIVE: to compare neural responses obtained with CE-Chirp® LS stimulus to those obtained with Clicks at 70 dB nHL in hearing infants, in order to analyze advantages in using CE-Chirp® LS.

METHODS: Eighteen infants with normal hearing were evaluated with Eclipse EP25 ABR System. Clicks and CE-Chirp® LS stimuli were presented using ER-3A insert earphones at 70 dB nHL, rate 45.1/s, and alternating polarity. A 30 Hz high-pass and 1500 Hz low-pass filter was applied, and ±40 μV artifact rejection level. Absolute latency of waves I, III and V and their interpeak intervals I-III, III-V and I-V were measured, as well as interaural difference for wave V and interpeak I-V, and wave V amplitude.

RESULTS: Although 18 infants were included in the study, it was possible to collect data only in 30 ears for Click stimulus, and 33 ears for CE-Chirp® LS, according to exclusion criteria. It was possible to record waves I, III, and V for both stimuli at 70 dB nHL in all normal-hearing infants. CE-Chirp® LS stimulus evoked a higher wave V amplitude than Click (p < 0.001). Wave I absolute latency was statistically different between stimuli (p < 0.001), being delayed for CE-Chirp® LS. Wave III absolute latency was statistically different between stimuli only for the right ear (p = 0.021), and wave V absolute latency was similar in both stimuli (p = 0.210). Interpeak intervals I-III and I-V were statistically different between stimuli (p < 0.001), being reduced for CE-Chirp® LS. Interpeak interval III-V was different between the stimuli only for right ears (p = 0.006). There was no difference between stimuli for interaural difference wave V (p = 1.33) and interaural difference interpeak I-V (p = 0.409).

CONCLUSION: It is possible to use CE-Chirp® LS stimulus in order to analyze neural synchrony in infants at 70 dB nHL, since better morphology waveforms were observed, and higher wave V amplitudes could be recorded. We suggest that new studies with infants with neurological disabilities and various hearing status, to observe how CE-Chirp® LS stimulus evokes neural responses in these conditions.

PMID:34198155 | DOI:10.1016/j.ijporl.2021.110819

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Nevin Manimala Statistics

Machine learning-based analysis of operator pupillary response to assess cognitive workload in clinical ultrasound imaging

Comput Biol Med. 2021 Jun 20;135:104589. doi: 10.1016/j.compbiomed.2021.104589. Online ahead of print.

ABSTRACT

INTRODUCTION: Pupillometry, the measurement of eye pupil diameter, is a well-established and objective modality correlated with cognitive workload. In this paper, we analyse the pupillary response of ultrasound imaging operators to assess their cognitive workload, captured while they undertake routine fetal ultrasound examinations. Our experiments and analysis are performed on real-world datasets obtained using remote eye-tracking under natural clinical environmental conditions.

METHODS: Our analysis pipeline involves careful temporal sequence (time-series) extraction by retrospectively matching the pupil diameter data with tasks captured in the corresponding ultrasound scan video in a multi-modal data acquisition setup. This is followed by the pupil diameter pre-processing and the calculation of pupillary response sequences. Exploratory statistical analysis of the operator pupillary responses and comparisons of the distributions between ultrasonographic tasks (fetal heart versus fetal brain) and operator expertise (newly-qualified versus experienced operators) are performed. Machine learning is explored to automatically classify the temporal sequences into the corresponding ultrasonographic tasks and operator experience using temporal, spectral, and time-frequency features with classical (shallow) models, and convolutional neural networks as deep learning models.

RESULTS: Preliminary statistical analysis of the extracted pupillary response shows a significant variation for different ultrasonographic tasks and operator expertise, suggesting different extents of cognitive workload in each case, as measured by pupillometry. The best-performing machine learning models achieve receiver operating characteristic (ROC) area under curve (AUC) values of 0.98 and 0.80, for ultrasonographic task classification and operator experience classification, respectively.

CONCLUSION: We conclude that we can successfully assess cognitive workload from pupil diameter changes measured while ultrasound operators perform routine scans. The machine learning allows the discrimination of the undertaken ultrasonographic tasks and scanning expertise using the pupillary response sequences as an index of the operators’ cognitive workload. A high cognitive workload can reduce operator efficiency and constrain their decision-making, hence, the ability to objectively assess cognitive workload is a first step towards understanding these effects on operator performance in biomedical applications such as medical imaging.

PMID:34198044 | DOI:10.1016/j.compbiomed.2021.104589

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Nevin Manimala Statistics

Volk Eye Check Ocular Measurement Device for Objective Periorbital Measurements: A Prospective Study

J Cosmet Dermatol. 2021 Jul 1. doi: 10.1111/jocd.14323. Online ahead of print.

ABSTRACT

PURPOSE: To report the reproducibility and repeatability of periocular biometric measurements using Volk Eye Check Ocular measurement device.

METHODS: Prospective, single blind, comparative study. Two experts performed digital photography of 100 volunteers using the standard photography technique using Oculoplasty module of the Volk Eye Check ocular measurement device. Each expert photographed the volunteer twice, to obtain two sets of automated printouts of 13 periorbital biometrics that were measured automatically by the ocular measurement device. Bland Altman plot and Multiple comparisons of Means from Linear mixed-effects model fit by REML using simultaneous contrasts with p values reported by Bonferroni method were used as statistical tests to analyze following parameters: MRD-1 (margin reflex distance-1), MRD-2 (margin reflex distance-2), PFH (palpebral fissure height), HVID (horizontal visible iris diameter), ALL (aperture length at lateral limbus) and ALM (aperture length at medial limbus).

RESULTS: The mean inter-observer difference in measurement (mm) was as follows: MRD1 (0.04), MRD2 (0.02), HVID (0.01), PFH (0.03), ALL (0.05), ALM (0.08). The mean intra-observer difference in measurement (mm) was as follows: MRD1 (0.02), MRD2 (0.09), HVID (0.0), PFH (0.09), ALL (0.06), ALM (0.05).

CONCLUSION: Periorbital biometric measurements using Volk Eye Check ocular measurement device are highly reproducible and repeatable. The oculoplasty module of Volk Eye Check ocular measurement device can provide reliable periorbital measurements for routine clinical use, and for objective clinical studies.

PMID:34197683 | DOI:10.1111/jocd.14323

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Nevin Manimala Statistics

Evaluation Of Serum Insulin-Like Growth Factor-1, Insulin, Glucose Levels in Patients With Adolescent And Post-adolescent Acne

J Cosmet Dermatol. 2021 Jul 1. doi: 10.1111/jocd.14327. Online ahead of print.

ABSTRACT

OBJECTIVES: There are many endogenous and exogenous factors that cause acne formation. This study aimed to determine whether the acne severity in patients with various age ranges is associated with serum insulin-like growth factor, insulin, and glucose and to identify how much they affect the acne severity.

MATERIALS AND METHODS: In this case-control prospective study, 44 patients with acne vulgaris and 44 age- and gender-matched control subjects without acne were evaluated. Patients and the control group were divided into two age groups as adolescence and post-adolescence. According to the Global Acne Scoring System (GASS) of the acne group, the acne score grades between 0-44 were calculated. The correlations between the IGF-1, insulin, glucose levels and acne grades were calculated in each group.

RESULTS: In our study, the acne scores and serum IGF-1 levels were found to be significantly higher in patients under the age of 21 than patients over the age of 21. There was a statistically significant difference in acne score between the two groups. However, there was no statistically significant difference between the serum IGF-1, insulin, and glucose levels of the acne group and the control group.

CONCLUSION: In this study, it has been revealed that IGF 1 is effective at the pathogenesis of acne in adolescence.

PMID:34197685 | DOI:10.1111/jocd.14327

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Evaluation of the Efficacy and Safety of Platelet Rich Plasma injection in treatment of Rosacea

Dermatol Ther. 2021 Jul 1:e15049. doi: 10.1111/dth.15049. Online ahead of print.

ABSTRACT

Rosacea is a chronic relapsing inflammatory skin disease, with a high prevalence among adults. Treatment of rosacea is difficult, with high rate of recurrence. Due to the strong anti- inflammatory and antibacterial effects of platelet rich plasma, it was used in the medicine for treating many inflammatory diseases. To evaluate the role of platelet rich plasma injection in treatment of rosacea. The study was carried on 40 patients with rosacea. They were treated by platelet rich plasma injection in right side of the face (group A) and platelet poor plasma injection in left side (group B). They underwent one session every 2 weeks for 3 months (6 sessions). The patients were assessed clinically before and after treatment by the Rosacea grading scale. Skin biopsies were taken to evaluate the clinical results. There was a statistically significant decrease in Rosacea grading scale after treatment with platelet rich plasma injection, 50% of the patients showed excellent improvement and 50% showed good improvement. The improvement was significantly better in group A than B. There was marked decrease in inflammatory cells by haematoxylin and eosin stain, and decrease in expression of nuclear factor kappa βeta after treatment with platelet rich plasma. PRP was effective and safe technique in treatment of rosacea and alternative to other systemic modalities, especially if they are contraindicated. This article is protected by copyright. All rights reserved.

PMID:34197656 | DOI:10.1111/dth.15049

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The evolution of histological changes suggestive of antibody-mediated injury, in the presence and absence of donor-specific anti-HLA antibodies

Transpl Int. 2021 Jul 1. doi: 10.1111/tri.13964. Online ahead of print.

ABSTRACT

The interplay between donor-specific anti-HLA antibodies (HLA-DSA), histology of active antibody-mediated rejection (aABMRh ), transplant glomerulopathy (cg) and graft failure in kidney transplantation remains insufficiently understood. We performed a single-center cohort study (n=1000) including 2761 protocol and 833 indication biopsies. Patients with pre-transplant HLA-DSA were more prone to develop aABMRh (OR 22.7, 95% CI, 11.8 – 43.7, p<0.001), cg (OR 5.76, 95% CI, 1.67 – 19.8, p=0.006) and aABMRh/cg (OR 19.5, 95% CI, 10.6 – 35.9, p<0.001). The negative impact of pre-transplant HLA-DSA on graft survival (HR 2.12, 95% CI, 1.41 – 3.20, p<0.001) was partially mediated through aABMRh and cg occurrence. When adjusted for time-dependent HLA-DSA (HR 4.03, 95% CI, 2.21 – 7.15, p=0.002), graft failure was only affected by aABMRh when cg was evident. In HLA-DSA negative patients, aABMRh was associated with impaired graft outcome only when evolving to cg (HR 1.32, 95% CI, 1.07 – 1.61, p=0.008). We conclude that the kinetics of HLA-DSA are important to estimate the rate of graft failure, and that histological follow-up is necessary to discover, often subclinical, ABMR and cg. In the absence of HLA-DSA, patients experience similar histological lesions and the evolution to transplant glomerulopathy associates with impaired graft outcome.

PMID:34197662 | DOI:10.1111/tri.13964