Lumbar Spine Anatomy in Supine versus Weight- Bearing Magnetic Resonance Imaging: Detecting Significant Positional Changes and Testing Reliability of Quantification

Mahato Niladri Kumar,Maharaj Paramanand,Clark Brian C. 대한척추외과학회 2024 Asian Spine Journal Vol.18 No.1

Study Design: Testing between and within group differences and assessing reliability of measurements. Purpose: To study and compare lumbar spine morphology in supine and weight-bearing (WB) magnetic resonance imaging (MRI). Overview of Literature: Upright lumbar MRI may uncover anatomical changes that may escape detection when using conventional supine imaging. This study quantified anatomical dimensions of the lumbar spine in the supine and WB MRI, compared specific morphometric differences between them, and tested the intra-rater reliability of the measurements. Repeated measures analysis was used to compare within- and between-session measurements performed on the supine and WB images. Reliability and agreement were assessed by calculating intraclass correlation (ICC) coefficient. Methods: Data from 12 adults without any history of back pain were used in this study. Sagittal T2-weighted images of the lumbar spine were acquired in the supine and WB positions twice (in two separate sessions scheduled within a week). Linear, angular dimensions, and cross-sectional areas (CSAs) were measured using proprietary software. Supine and WB data acquired from the two imaging sessions were tested for intra-rater reliability. Quantified data were normalized for each session to test the significance of differences. ICC was calculated to test the reliability of the measurements. Results: Linear, angular, and CSA measurements demonstrated strong within-position (supine and WB) correlations (r-values, 0.75–0.97). Between-position (supine vs. WB) differences were significant for all measured dimensions (p<0.05). Between-session measurements demonstrated a strong correlation (r-values, 0.64–0.83). Calculated ICC showed strong agreement among the measurements. Conclusions: Anatomical dimensions of the lumbar spine may demonstrate consistent and significant differences between supine and WB MRI for specific structural parameters.

Multi-variate Empirical Mode Decomposition (MEMD) for ambient modal identification of RC road bridge

Mahato, Swarup,Hazra, Budhaditya,Chakraborty, Arunasis Techno-Press 2020 Structural monitoring and maintenance Vol.7 No.4

In this paper, an adaptive MEMD based modal identification technique for linear time-invariant systems is proposed employing multiple vibration measurements. Traditional empirical mode decomposition (EMD) suffers from mode-mixing during sifting operations to identify intrinsic mode functions (IMF). MEMD performs better in this context as it considers multi-channel data and projects them into a n-dimensional hypercube to evaluate the IMFs. Using this technique, modal parameters of the structural system are identified. It is observed that MEMD has superior performance compared to its traditional counterpart. However, it still suffers from mild mode-mixing in higher modes where the energy contents are low. To avoid this problem, an adaptive filtering scheme is proposed to decompose the interfering modes. The Proposed modified scheme is then applied to vibrations of a reinforced concrete road bridge. Results presented in this study show that the proposed MEMD based approach coupled with the filtering technique can effectively identify the parameters of the dominant modes present in the structural response with a significant level of accuracy.

Citrus waste derived nutra-/pharmaceuticals for health benefits: Current trends and future perspectives

Mahato, Neelima,Sharma, Kavita,Sinha, Mukty,Cho, Moo Hwan Elsevier 2018 Journal of Functional Foods Vol.40 No.-

<P><B>Abstract</B></P> <P>Citrus are one of the most widely cultivated fruit crops. Citrus fruits are rich source of essential vitamins, minerals, fibers and bioactive phytochemicals, such as alkaloids, carotenoids, nitrogenous compounds and polyphenolics. The by-products derived from citrus wastes are considered to be an economic and renewable source for valuable compounds which can be used in pharmaceutical, nutraceutical, food and cosmetic industries. The review presents a detailed description on the recent advances with emphasis on the citrus derived nutraceuticals as potential source for various biological properties and physiological roles, such as anti-carcinogenicity, anti-mutagenicity, anti-allergenicity, anti-ageingactivitiy, and natural as well as important constituent in synthetic antioxidants. A comprehensive description on the citrus derived food and drinks as well as nutritious feed for animals has also been included.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Citrus wastes are rich in phytochemicals, viz., phenolics, flavonoids, etc. </LI> <LI> Citrus bioactive compounds are antioxidant, antimicrobial, anticarcinogenic, etc. </LI> <LI> Citrus derived compounds can be used as nutra-/pharmaceuticals. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Graphene integrated polyaniline nanostructured composite coating for protecting steels from corrosion: Synthesis, characterization, and protection mechanism of the coating material in acidic environment

Mahato, N.,Cho, M.H. Butterworth Scientific ; Elsevier Science Ltd 2016 Construction and Building Materials Vol.115 No.-

We report on the synthesis, characterization and application of highly crystalline graphene integrated polyaniline nanostructured composites as corrosion protection coatings. The coated surface showed a decline in corrosion current up to ~3-4 orders of magnitude in 0.1M HCl. Composite coating with 1.92wt.% graphene loading showed best protection. SEM images obtained after the corrosion tests reveal several pits on the coated steel surface with network like structures. A plausible mechanism of the corrosion protection mechanism of the composite coating has been proposed to explain the fate of the material in acidic environment.

Effect of Cenosphere Sizes on Mechanical, Thermal and Rheological Properties of the Lightweight Cementitious Composites

Mahato, Jyoti(마하토 죠티),Moon, Juhyuk(문주혁) 한국콘크리트학회 2021 한국콘크리트학회 학술대회 논문집 Vol.33 No.2

이 연구는 다양한 크기의 세노스피어 입자가 경량 시멘트 복합체의 기계적, 열적 및 유동학적 특성에 미치는 영향을 조사하는 것임. 4가지 다른 입자 크기의 세노스피어가 경량 시멘트 복합체에 미치는 영향을 다양하게 연구하였음. The purpose of this study is to investigate the effects of different sizes of cenospheres particles on the mechanical, thermal, and rheological properties of the lightweight cementitious composites. Four different sizes of cenospheres are studied in conjuction with various particle sizes, crushing strength, and proportions.

Active vibration control of smart composite structures in hygrothermal environment

Mahato, P.K.,Maiti, D.K. Techno-Press 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.44 No.2

The composite materials may be exposed to environmental (thermal or hygral or both) condition during their service life. The effect of environmental condition is usually adverse from the point of view of design of composite structures. In the present research study the effect of hygrothermal condition on the design of laminated composite structures is investigated. The active fiber composite (AFC) which may be utilized as actuator or sensor is considered in the present analysis. The sensor layer is used to sense the level of response of the composite structures. The sensed voltage is fed back to the actuator through the controller. In this study both displacement and velocity feedback controllers are employed to reduce the response of the composite laminate within acceptable limit. The Newmark direct time integration scheme is employed along with modal superposition method to improve the computational efficiency. It is observed from the numerical study that the laminated composite structures become weak in the presence of hygrothermal load. The response of the structure can be brought to the acceptable level once the AFC layer is activated through the feedback loop.

Preorganized Chromophores Facilitate Triplet Energy Migration, Annihilation and Upconverted Singlet Energy Collection

Mahato, Prasenjit,Yanai, Nobuhiro,Sindoro, Melinda,Granick, Steve,Kimizuka, Nobuo American Chemical Society 2016 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.138 No.20

<P>Photon upconversion (UC) based on triplet triplet annihilation (TTA) has the potential to enhance significantly photovoltaic and photocatalytic efficiencies by harnessing sub-bandgap photons, but the progress of this field is held back by the chemistry problem of how to preorganize multiple chromophores for efficient UC under weak solar irradiance. Recently, the first maximization of UC quantum yield at solar irradiance was achieved using fast triplet energy migration (TEM) in metal organic frameworks (MOFs) with ordered acceptor arrays, but at the same time, a trade-off between fast TEM and high fluorescence efficiency was also found. Here, we provide a solution for this trade-off issue by developing a new strategy, triplet energy migration, annihilation and upconverted singlet energy collection (TEM-UPCON). The porous structure of acceptor-based MOF crystals allows triplet donor molecules to be accommodated without aggregation. The surface of donor-doped MOF nanocrystals is modified with highly fluorescent energy collectors through coordination bond formation. Thanks to the higher fluorescence quantum yield of surface-bound collectors than parent MOFs, the implementation of the energy collector greatly improves the total UC quantum yield. The UC quantum yield maximization behavior at ultralow excitation intensity was retained because the TTA events take place only in the MOF acceptors. The TEM-UPCON concept may be generalized to collectors with various functions and would lead to quantitative harvesting of upconverted energy, which is difficult to achieve in common molecular diffusion-based systems.</P>

Multiresponsive soft actuator for natural and complex motions in robotic interactions

Manmatha Mahato,Il-Kwon Oh 대한기계학회 2023 대한기계학회 춘추학술대회 Vol.2023 No.11

Development of High Strength Lightweight Cementitious Composite using Cenosphere

Jyoti Mahato(마하토 죠티),Juhyuk Moon(문주혁) 한국콘크리트학회 2021 한국콘크리트학회 학술대회 논문집 Vol.33 No.1

Active vibration control of smart composite structures in hygrothermal environment

P.K. Mahato,D.K. Maiti 국제구조공학회 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.44 No.2

The composite materials may be exposed to environmental (thermal or hygral or both) condition during their service life. The effect of environmental condition is usually adverse from the point of view of design of composite structures. In the present research study the effect of hygrothermal condition on the design of laminated composite structures is investigated. The active fiber composite (AFC) which may be utilized as actuator or sensor is considered in the present analysis. The sensor layer is used to sense the level of response of the composite structures. The sensed voltage is fed back to the actuator through the controller. In this study both displacement and velocity feedback controllers are employed to reduce the response of the composite laminate within acceptable limit. The Newmark direct time integration scheme is employed along with modal superposition method to improve the computational efficiency. It is observed from the numerical study that the laminated composite structures become weak in the presence of hygrothermal load. The response of the structure can be brought to the acceptable level once the AFC layer is activated through the feedback loop.