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1.
Sci Rep ; 13(1): 8200, 2023 May 21.
Article in English | MEDLINE | ID: mdl-37211551

ABSTRACT

Thermal losses through weak building envelope is responsible for global current energy crises. Application of artificial intelligence and drone setups in green buildings can help in providing the sustainable solution the world is striving for years. The contemporary research incorporates a novel concept of measuring the wearing thermal resistances in the building envelope with the aid of a drone system. The above procedure conducts a throughout building analysis by considering three prime environmental parameters such as wind speed (WS), relative humidity (RH) and dry bulb temperature (DBT) with the aid of drone heat mapping procedure. The novelty of the study can be interpreted by the fact that prior researches have never explored the building envelope through a combination of drone and climatic conditions as variables in building areas difficult to access, thereby providing an easier, risk free, cost effective and efficient reading. Validation of the formula is authenticated by employing artificial intelligence-based software's which are applied for data prediction and optimization. Artificial models are established to validate the variables for each output from the specified number of climatic inputs. The pareto-optimal conditions attained after analysis are 44.90% RH, 12.61 °C DBT and 5.20 km/h WS. The variables and thermal resistance were validated with response surface methodology method, thereby presenting lowest error rate and comprehensive R2 value, which are 0.547 and 0.97, respectively. Henceforth, employing drone-based technology in estimating building envelope discrepancies with the novel formula, yields consistent and effective assessment for development of green building, simultaneously reducing time and cost of the experimentation.

2.
Clin Biomech (Bristol, Avon) ; 88: 105440, 2021 08.
Article in English | MEDLINE | ID: mdl-34329857

ABSTRACT

BACKGROUND: Carpal tunnel syndrome patients demonstrate diminished motion of the median nerve and fibrotic changes in the subsynovial connective tissue within the carpal tunnel. Currently, there are few prognostic factors to help predict the outcome of commonly performed treatments including surgical carpal tunnel release and corticosteroid injections. This study aimed to non-invasively assess the changes in the dynamic response of the subsynovial tissue relative to tendon motion after the intervention and to correlate this with disease severity. METHODS: A total of 145 patients with carpal tunnel syndrome were recruited into this study. Clinical and demographic data, electrophysiological severity and dynamic ultrasound images were collected before and after treatment, either by injection or surgery. The relative motion of the subsynovial tissue with the underlying middle finger flexor digitorum superficialis tendon was measured using a speckle tracking algorithm and was expressed as a shear index (SI). Baseline and follow-up data, the association between change in SI and severity, and the role of treatment modality were analyzed and statistically compared. FINDINGS: Overall, there was a significant increase (more relative motion) after treatment in the mean shear index from 79.9% (±15.4% SD) to 82.9% (±14.8% SD) (p = 0.03). Secondary analyses showed that this change was mostly present in those with mild disease severity undergoing surgery (p = 0.01). INTERPRETATION: This study shows that the relative subsynovial tissue movement increases in patients after intervention. The present study lays a foundation for future studies to non-invasively assess the role of carpal tunnel dynamics in response to treatment.


Subject(s)
Carpal Tunnel Syndrome , Carpal Tunnel Syndrome/diagnostic imaging , Carpal Tunnel Syndrome/surgery , Connective Tissue/diagnostic imaging , Humans , Median Nerve , Tendons/diagnostic imaging , Tendons/surgery , Ultrasonography
3.
J Ultrasound Med ; 40(8): 1555-1568, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33073880

ABSTRACT

OBJECTIVES: The mobility (transverse movement) of the median nerve (MN) is decreased in patients with carpal tunnel syndrome and can be measured noninvasively by ultrasound. To date, there are few prognostic features to help predict the outcome of 2 commonly performed treatments: surgical carpal tunnel release and corticosteroid injection. This study aimed to assess the changes in nerve mobility after the intervention and to correlate this with treatment and the disease severity. METHODS: A total of 181 patients with carpal tunnel syndrome with different electrophysiologic severities were recruited and assessed by dynamic ultrasound scanning of the MN before and after treatment. The dynamic ultrasound images were collected while the patients performed finger and wrist flexion. RESULTS: For both injection and carpal tunnel release, the nerve displacement increased with wrist flexion, from a mean ± SD of 7.0 ± 2.4 to 7.9 ± 2.7 mm (P < .005). Patients who underwent surgery showed greater improvement (P < .005) in nerve mobility compared to those who underwent injection. We also observed that the increase in nerve mobility was predominantly in patients with more nerve damage at baseline. CONCLUSIONS: This study shows that the dynamic behavior of the MN changes in response to treatment and lays a foundation for future studies to assess the prognostic potential of nerve mobility measurement.


Subject(s)
Carpal Tunnel Syndrome , Median Nerve , Carpal Tunnel Syndrome/diagnostic imaging , Carpal Tunnel Syndrome/surgery , Humans , Median Nerve/diagnostic imaging , Ultrasonography , Wrist/diagnostic imaging , Wrist Joint/diagnostic imaging
4.
Med Biol Eng Comput ; 58(9): 2107-2118, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32671675

ABSTRACT

In this study, we propose a computational characterization technique for obtaining the material properties of axons and extracellular matrix (ECM) in human brain white matter. To account for the dynamic behavior of the brain tissue, data from time-dependent relaxation tests of human brain white matter in different strain rates are extracted and formulated by a visco-hyperelastic constitutive model consisting of the Ogden hyperelastic model and the Prony series expansion. Through micromechanical finite element simulation, a derivative-free optimization framework designed to minimize the difference between the numerical and experimental data is used to identify the material properties of the axons and ECM. The Prony series expansion parameters of axons and ECM are found to be highly affected by the Prony series expansion coefficients of the brain white matter. The optimal parameters of axons and ECM are verified through micromechanical simulation by comparing the averaged numerical response with that of the experimental data. Moreover, the initial shear modulus and the reduced shear modulus of the axons are found for different strain rates of 0.0001, 0.01, and 1 s-1. Consequently, first- and second-order regressions are used to find relations for the prediction of the shear modulus at the intermediate strain rates. Graphical Abstract The applied procedure for characterization of brain white matter micro-level constituents. The macro-level experimental data in different strain rates are used in the context of simulation-based optimization to obtain the properties of axons and extracellular matrix material.


Subject(s)
White Matter/physiology , Animals , Axons/physiology , Axons/ultrastructure , Biomechanical Phenomena , Biomedical Engineering , Brain Injuries, Traumatic/etiology , Brain Injuries, Traumatic/physiopathology , Computer Simulation , Elasticity , Extracellular Matrix/physiology , Extracellular Matrix/ultrastructure , Finite Element Analysis , Humans , Models, Neurological , Stress, Mechanical , Viscosity , White Matter/anatomy & histology
5.
J Mech Behav Biomed Mater ; 102: 103475, 2020 02.
Article in English | MEDLINE | ID: mdl-31627069

ABSTRACT

In this paper, the dynamic behavior of bovine brain tissue, measured from in-vitro unconfined compression tests, is examined and represented through a viscoelastic biphasic model. The experiments have been carried out under three compression speeds of 10, 100, and 1000 mm/s. The results exhibited significant rate-dependent behavior. The brain tissue is modeled as a biphasic continuum consisting of a compressible solid matrix, fully saturated with an incompressible interstitial fluid. The governing equations based on conservation of mass and momentum are used to describe the solid-fluid interactions. An inverse scheme is employed in which a finite element model runs iteratively to optimize constitutive constants. The obtained material parameters of the proposed biphasic model show relatively good agreement (R2 ≥ 0.96) with the experimental tissue mechanical responses at different rates. The model can successfully capture the key aspects of the rate-dependency for both solid and fluid phases under large strain deformation. This poro-hyper viscoelastic model can effectively estimate the global and local rate-dependent tissue deformations, the spatial variations in pore spaces, hydrostatic pressure as well as fluid diffusion through the tissue.


Subject(s)
Brain , Models, Biological , Animals , Cattle , Elasticity , Finite Element Analysis , Pressure , Stress, Mechanical , Viscosity
6.
Biomech Model Mechanobiol ; 19(2): 621-632, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31612343

ABSTRACT

In this paper, the dynamic behavior of bovine brain tissue, measured from a set of in vitro experiments, is investigated and represented through a nonlinear viscoelastic constitutive model. The brain samples were tested by employing unconfined compression tests at three different deformation rates of 10, 100, and 1000 mm/s. The tissue exhibited a significant rate-dependent behavior with different compression speeds. Based on the parallel rheological framework approach, a nonlinear viscoelastic model that captures the key aspects of the rate dependency in large-strain behavior was introduced. The proposed model was numerically calibrated to the tissue test data from three different deformation rates. The determined material parameters provided an excellent constitutive representation of tissue response in comparison with the test results. The obtained material parameters were employed in finite element simulations of tissue under compression loadings and successfully verified by the experimental results, thus demonstrating the computational compatibility of the proposed material model. The results of this paper provide groundwork in developing a characterization framework for large-strain and rate-dependent behavior of brain tissue at moderate to high strain rates which is of the highest importance in biomechanical analysis of the traumatic brain injury.


Subject(s)
Brain/physiology , Models, Biological , Animals , Biomechanical Phenomena , Cattle , Compressive Strength , Elasticity , Finite Element Analysis , Nonlinear Dynamics , Stress, Mechanical , Viscosity
7.
J Inequal Appl ; 2017(1): 297, 2017.
Article in English | MEDLINE | ID: mdl-29213202

ABSTRACT

In this paper, we propose and analyze a hybrid iterative method for finding a common element of the set of solutions of a generalized equilibrium problem, the set of solutions of a variational inequality problem, and the set of fixed points of a relatively nonexpansive mapping in a real Banach space. Further, we prove the strong convergence of the sequences generated by the iterative scheme. Finally, we derive some consequences from our main result. Our work is an improvement and extension of some previously known results recently obtained by many authors.

8.
Food Chem ; 194: 61-7, 2016 Mar 01.
Article in English | MEDLINE | ID: mdl-26471527

ABSTRACT

An enzyme free glucose sensor was prepared by a molecular imprinting method (MIP). The procedure was developed by in situ preparation of a new polyvinyl acetate (PVA) electrode reinforced by MnO2/CuO loaded on graphene oxide (GO) nanoparticles (PVA/MnO2@GO/CuO). The nanocomposite was modified in the presence of glucose and then imprinted. A carbone paste method with voltammetry was used in the fabrication of the sensor from prepared MIP nanocomposite. PVA/MnO2@GO/CuO electrode was characterized by X-ray diffraction, FT-IR spectroscopy and scanning electron microscopy. Electrocatalytic activity of the electrode toward glucose oxidation was then investigated by cyclic voltammetry in alkaline medium. The results show that the response of PVA/MnO2@GO/CuO MIP is much higher than PVA/MnO2@GO/CuO non-imprinted electrode toward glucose oxidation. The detection limit was 53µM, and the sensor responses are linear for concentrations from 0.5 to 4.4mM. Relative standard deviations for intra- and inter-day determination were less than 6.0%. The relative recoveries for different samples were 96%.


Subject(s)
Copper/chemistry , Glucose/chemistry , Manganese Compounds/chemistry , Molecular Imprinting/methods , Nanoparticles/chemistry , Oxides/chemistry , Electrodes , Graphite/chemistry , Oxidation-Reduction , Polyvinyls/analysis
9.
Bioresour Technol ; 131: 555-9, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23415940

ABSTRACT

In this study, chitosan and nano-chitosan were used as flocculants agents for harvesting microalga Nannochloropsis sp. chitosan was modified to nano-chitosan by crosslinking with sodium tripolyphosphate. The effects of type and dosage of flocculants and the pH of the culture were investigated on biomass recovery. Optimum dosages for both bio-flocculants were found. The results showed that the dosage of flocculant consumption decreases by 40% and biomass recovery increases by 9% when nano-chitosan instead of chitosan is used as flocculant agent. Also, the recycled water from the harvesting process was reused which increases the growth of microalgae by about 7%. Finally, the cost analysis of harvesting process showed the feasibility of using nano-chitosan as flocculation agent.


Subject(s)
Batch Cell Culture Techniques/methods , Bioreactors/microbiology , Chitosan/chemistry , Microalgae/growth & development , Microalgae/isolation & purification , Nanostructures/chemistry , Cell Proliferation , Cell Survival
10.
Lipids Health Dis ; 9: 96, 2010 Sep 07.
Article in English | MEDLINE | ID: mdl-20822508

ABSTRACT

BACKGROUND: Low level of high density lipoprotein cholesterol (HDL-C) has high prevalence in the Tehran Lipid and Glucose Study (TLGS) cohort. About 50% of the inter-individual variation in serum HDL-C levels is genetically determined. Polymorphisms in cholesteryl ester transfer protein (CETP) and hepatic lipase (LIPC) genes have been found to be associated with the metabolism and serum concentration of the HDL-C. OBJECTIVES: To determine the association between Taq1B polymorphism in CETP gene and -514C/T polymorphism in LIPC gene with serum lipid levels and lipid peroxidation in a subgroup of the TLGS population. RESULTS: Serum HDL-C level had significant association with CETP Taq1B polymorphism and B2B2 subjects had the highest HDL-C levels compared to B2B1 and B1B1 genotypes (37.9 vs. 36.9 and 35.3 mg/dl, respectively; P = 0.01). However, carriers of "B1" allele, in comparison to the non carriers (B2B2), had significantly lower levels of TC (200.1 vs. 215.2 mg/dl; P = 0.005), HDL-C (35.8 vs. 37.9 mg/dl; P = 0.009) and malondialdehyde MDA (4.5 vs. 5.0 nmol/mL; P=0.031). Carriers of the "T" allele in -514C/T polymorphism in LIPC gene had higher means of HDL-C than non carriers (37.7 vs. 35.7 mg/dl, P = 0.04). No other association was found between -514C/T polymorphism and any other serum lipids or MDA level. CONCLUSION: This study demonstrates the association between Taq1B and -514C/T polymorphisms in the CETP and LIPC genes with the serum HDL-C levels.


Subject(s)
Cholesterol Ester Transfer Proteins/genetics , Cholesterol, HDL/blood , Dyslipidemias/genetics , Lipase/genetics , Polymorphism, Single Nucleotide , Adult , Aged , Aged, 80 and over , Cohort Studies , Cross-Sectional Studies , Dyslipidemias/blood , Female , Gene Frequency , Genetic Association Studies , Heterozygote , Humans , Iran , Lipids/blood , Male , Malondialdehyde/blood , Middle Aged , Polymorphism, Restriction Fragment Length , Promoter Regions, Genetic/genetics , Site-Specific DNA-Methyltransferase (Adenine-Specific)/metabolism , Vascular Diseases/genetics
11.
J Low Genit Tract Dis ; 8(1): 16-20, 2004 Jan.
Article in English | MEDLINE | ID: mdl-15874831

ABSTRACT

OBJECTIVE: To assess the feasibility and performance of direct visual inspection (DVI) of the cervix as a primary tool for the detection of premalignant lesions of the cervix (HPV/CIN 1 and CIN 2,3). SETTING: The early cancer detection unit at the Ain Shams University Maternity Hospital in Cairo, Egypt. SUBJECTS AND METHODS: The study included 2049 women. Cervical smears were obtained from all women for cytologic evaluation followed by direct visual inspection (DVI) of the cervix after painting with 5% acetic acid. Women whose smear reports showed abnormal cells suggestive of squamous intraepithelial lesion (SIL) or human papillomavirus (HPV) infection or those who showed abnormalities or acetowhite areas on direct visual inspection subsequently were referred for colposcopy and biopsy when appropriate. Colposcopy also was performed for women with negative DVI and negative smears if they had contact bleeding or chronic per vaginal discharge. RESULTS: Mean (SD) age of women included in the study was 39.9 (10.2) years with their mean (SD) parity 2.9 (1.1). Results of DVI were normal in 1916 women (93.4%) and showed abnormal acetowhite appearance in 133 (6.6%) women. There were 458 (22.4%) colposcopic examinations and 130 biopsies (6.34%) were carried out, picking up 83 cases of premalignant lesions (4.0%). Premalignant lesions were 80 HPV/CIN 1 and CIN 2,3. Direct visual inspection detected 71 of the 83 premalignant lesions (sensitivity, 85.5%; specificity, 96.8%; positive predictive value, 52.6%). Direct visual inspection missed one of the three samples showing CIN 2,3. Cervical cytologic analysis showed abnormal cells in 60 (2.9%) and identified only 14 of the premalignant lesions (sensitivity, 16.9%; specificity, 97.8%; positive predictive value, 23.3%). Twelve of the premalignant lesions had positive smear results and a negative DVI, with none of them being of a high grade. CONCLUSIONS: Direct visual inspection is feasible and had superior sensitivity compare with cervical cytologic analysis in detecting premalignant lesions of the cervix. Direct visual inspection can be used as a primary screening tool with a satisfactory low biopsy rate in low-resource settings or where cytologic services are suboptimal.

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