Displaying publications 21 - 40 of 10188 in total

Abstract:
Sort:
  1. Fulltext The effect of contact angles and capillary dimensions on the burst frequency of super hydrophilic and hydrophilic centrifugal microfluidic platforms, a CFD study
    Kazemzadeh A, Ganesan P, Ibrahim F, He S, Madou MJ
    PLoS One, 2013;8(9):e73002.
    PMID: 24069169 DOI: 10.1371/journal.pone.0073002
    This paper employs the volume of fluid (VOF) method to numerically investigate the effect of the width, height, and contact angles on burst frequencies of super hydrophilic and hydrophilic capillary valves in centrifugal microfluidic systems. Existing experimental results in the literature have been used to validate the implementation of the numerical method. The performance of capillary valves in the rectangular and the circular microfluidic structures on super hydrophilic centrifugal microfluidic platforms is studied. The numerical results are also compared with the existing theoretical models and the differences are discussed. Our experimental and computed results show a minimum burst frequency occurring at square capillaries and this result is useful for designing and developing more sophisticated networks of capillary valves. It also predicts that in super hydrophilic microfluidics, the fluid leaks consistently from the capillary valve at low pressures which can disrupt the biomedical procedures in centrifugal microfluidic platforms.
    Matched MeSH terms: Microfluidics/methods*; Microfluidic Analytical Techniques/methods
  2. Fulltext A Secure and Robust Compressed Domain Video Steganography for Intra- and Inter-Frames Using Embedding-Based Byte Differencing (EBBD) Scheme
    Idbeaa T, Abdul Samad S, Husain H
    PLoS One, 2016;11(3):e0150732.
    PMID: 26963093 DOI: 10.1371/journal.pone.0150732
    This paper presents a novel secure and robust steganographic technique in the compressed video domain namely embedding-based byte differencing (EBBD). Unlike most of the current video steganographic techniques which take into account only the intra frames for data embedding, the proposed EBBD technique aims to hide information in both intra and inter frames. The information is embedded into a compressed video by simultaneously manipulating the quantized AC coefficients (AC-QTCs) of luminance components of the frames during MPEG-2 encoding process. Later, during the decoding process, the embedded information can be detected and extracted completely. Furthermore, the EBBD basically deals with two security concepts: data encryption and data concealing. Hence, during the embedding process, secret data is encrypted using the simplified data encryption standard (S-DES) algorithm to provide better security to the implemented system. The security of the method lies in selecting candidate AC-QTCs within each non-overlapping 8 × 8 sub-block using a pseudo random key. Basic performance of this steganographic technique verified through experiments on various existing MPEG-2 encoded videos over a wide range of embedded payload rates. Overall, the experimental results verify the excellent performance of the proposed EBBD with a better trade-off in terms of imperceptibility and payload, as compared with previous techniques while at the same time ensuring minimal bitrate increase and negligible degradation of PSNR values.
    Matched MeSH terms: Video Recording/methods*; Data Compression/methods*
  3. Specimens as primary data: museums and 'open science'
    Schilthuizen M, Vairappan CS, Slade EM, Mann DJ, Miller JA
    Trends Ecol Evol, 2015 May;30(5):237-8.
    PMID: 25813120 DOI: 10.1016/j.tree.2015.03.002
    Matched MeSH terms: Ecology/methods*; Natural History/methods*
  4. [Abortion induced through massage]
    Havránek F
    Cesk Gynekol, 1977 Aug;42(7):532.
    PMID: 890794
    Matched MeSH terms: Abortion, Induced/methods*; Massage/methods*
  5. Bambara groundnut: an exemplar underutilised legume for resilience under climate change
    Mayes S, Ho WK, Chai HH, Gao X, Kundy AC, Mateva KI, et al.
    Planta, 2019 Sep;250(3):803-820.
    PMID: 31267230 DOI: 10.1007/s00425-019-03191-6
    MAIN CONCLUSION: Bambara groundnut has the potential to be used to contribute more the climate change ready agriculture. The requirement for nitrogen fixing, stress tolerant legumes is clear, particularly in low input agriculture. However, ensuring that existing negative traits are tackled and demand is stimulated through the development of markets and products still represents a challenge to making greater use of this legume. World agriculture is currently based on very limited numbers of crops, representing a significant risk to food supplies, particularly in the face of climate change which is expected to increase the frequency of extreme events. Minor and underutilised crops can help to develop a more resilient and nutritionally dense future agriculture. Bambara groundnut [Vigna subterranea (L.) Verdc.[, as a drought resistant, nitrogen-fixing, legume has a role to play. However, as with most underutilised crops, there are significant gaps in knowledge and also negative traits such as 'hard-to-cook' and 'photoperiod sensitivity to pod filling' associated with the crop which future breeding programmes and processing methods need to tackle, to allow it to make a significant contribution to the well-being of future generations. The current review assesses these factors and also considers what are the next steps towards realising the potential of this crop.
    Matched MeSH terms: Crop Production/methods; Cooking/methods
  6. Fulltext NMF-Based Approach for Missing Values Imputation of Mass Spectrometry Metabolomics Data
    Xu J, Wang Y, Xu X, Cheng KK, Raftery D, Dong J
    Molecules, 2021 Sep 24;26(19).
    PMID: 34641330 DOI: 10.3390/molecules26195787
    In mass spectrometry (MS)-based metabolomics, missing values (NAs) may be due to different causes, including sample heterogeneity, ion suppression, spectral overlap, inappropriate data processing, and instrumental errors. Although a number of methodologies have been applied to handle NAs, NA imputation remains a challenging problem. Here, we propose a non-negative matrix factorization (NMF)-based method for NA imputation in MS-based metabolomics data, which makes use of both global and local information of the data. The proposed method was compared with three commonly used methods: k-nearest neighbors (kNN), random forest (RF), and outlier-robust (ORI) missing values imputation. These methods were evaluated from the perspectives of accuracy of imputation, retrieval of data structures, and rank of imputation superiority. The experimental results showed that the NMF-based method is well-adapted to various cases of data missingness and the presence of outliers in MS-based metabolic profiles. It outperformed kNN and ORI and showed results comparable with the RF method. Furthermore, the NMF method is more robust and less susceptible to outliers as compared with the RF method. The proposed NMF-based scheme may serve as an alternative NA imputation method which may facilitate biological interpretations of metabolomics data.
    Matched MeSH terms: Computational Biology/methods*; Metabolomics/methods*
  7. Fulltext Indwelling pleural catheter for malignant pleural effusion with persistent air leak
    Ng BH, Ban AY, Low HJ, Faisal M
    BMJ Case Rep, 2022 Aug 19;15(8).
    PMID: 35985740 DOI: 10.1136/bcr-2021-248574
    Malignant pleural effusion with persistent air leak (PAL) is a rare manifestation of lung malignancy. We present a woman in her 50s with postpleuroscopy PAL. Pleural biopsy confirmed adenocarcinoma with detection of epidermal growth factor receptor mutation in exon 19. An indwelling pleural catheter (IPC) was inserted and connected to an Atrium Express Mini ambulatory drain. This procedure reduced the length of hospital stay. Autopleurodesis with resolution of PAL occurred at week 3 of IPC insertion.
    Matched MeSH terms: Drainage/methods; Pleurodesis/methods
  8. Efficient and easible biocatalysts: Strategies for enzyme improvement. A review
    Albayati SH, Nezhad NG, Taki AG, Rahman RNZRA
    Int J Biol Macromol, 2024 Sep;276(Pt 2):133978.
    PMID: 39038570 DOI: 10.1016/j.ijbiomac.2024.133978
    Owing to the environmental friendliness and vast advantages that enzymes offer in the biotechnology and industry fields, biocatalysts are a prolific investigation field. However, the low catalytic activity, stability, and specific selectivity of the enzyme limit the range of the reaction enzymes involved in. A comprehensive understanding of the protein structure and dynamics in terms of molecular details enables us to tackle these limitations effectively and enhance the catalytic activity by enzyme engineering or modifying the supports and solvents. Along with different strategies including computational, enzyme engineering based on DNA recombination, enzyme immobilization, additives, chemical modification, and physicochemical modification approaches can be promising for the wide spread of industrial enzyme usage. This is attributed to the successful application of biocatalysts in industrial and synthetic processes requires a system that exhibits stability, activity, and reusability in a continuous flow process, thereby reducing the production cost. The main goal of this review is to display relevant approaches for improving enzyme characteristics to overcome their industrial application.
    Matched MeSH terms: Biotechnology/methods; Protein Engineering/methods
  9. Fulltext Effects of foam mat-drying condition on physicochemical and antioxidant properties of instant Physalis angulata L. enriched with Moringa oleifera L. extract
    Widhanti A, Iwansyah AC, Yelliantty, Kurniawan T, Pramareti GMJ, Indriati A, et al.
    An Acad Bras Cienc, 2024;96(suppl 3):e20240006.
    PMID: 39630800 DOI: 10.1590/0001-3765202420240006
    Food drying is still a crucial step in the food manufacturing process for food preservation, and the foam-mat drying method can be utilized to further enhance food preservation. This study aims to develop an instant L. powder enriched with Moringa oleifera L. extract and to evaluate the effect of foam mat drying conditions on physicochemical and antioxidant properties.The experimental design used a factorial completely randomized block design (FCBD), with triplicates. Based on the results showed that the interaction between the different forms of moringa extract, when added, and drying temperature affected color, water activity, bulk density, hygroscopicity, total acid titration, moisture content, ABTS, antioxidant activity and total flavonoid contents (p<0.05) but did not affect solubility, total soluble solids, flow rate, pH, DPPH antioxidant activity and total phenolic contents (p>0.05). Samples dried at a temperature of 70°C (T3), both liquid (F1) and microencapsulated (F2), exhibited the best physicochemical and antioxidant properties. These findings confirmed the suitability of foam mat drying to produce P. angulata instant powder enriched with M. oleifera extract for functional food ingredients.
    Matched MeSH terms: Desiccation/methods; Food Preservation/methods
  10. A critique of Rajendran et al.'s "A critical and recent developments on adsorption technique for removal of heavy metals from wastewater - A review"
    Chu KH, Bollinger JC
    Chemosphere, 2024 Nov;368:143761.
    PMID: 39551194 DOI: 10.1016/j.chemosphere.2024.143761
    This critique examines a review article in this journal on adsorption techniques for removing metal ions from wastewater. The article is marred by several flaws, including tortured phrases, miscitations, incoherent statements, and factual inaccuracies. These problems weaken the article's clarity and reliability, raising doubts about the authors' understanding of the subject. As a result, the review's credibility is compromised, limiting its value as a reliable resource for researchers. This critique highlights these issues, stressing the importance of accuracy and rigor in scientific writing.
    Matched MeSH terms: Waste Disposal, Fluid/methods; Water Purification/methods
  11. The concept and implementation of "distributed learning"--our early experience
    Loh LC, Lai NM, Nalliah S, Jutti RC
    Ann Acad Med Singap, 2007 Oct;36(10):867-70.
    PMID: 17987241
    Matched MeSH terms: Education, Medical/methods*; Teaching/methods*
  12. Temperature-based investigation of rhamnolipids congeners production by the non-pathogenic Burkholderia thailandensis E264 using LC-QToF-MS metabolomics
    Mohammed Yousuf Abdi S, Azizan KA, Syed Abdullah SS, Samsu ZA
    Metabolomics, 2024 Dec 30;21(1):14.
    PMID: 39738744 DOI: 10.1007/s11306-024-02205-z
    INTRODUCTION: Burkholderia thailandensis E264 is a non-pathogenic soil bacterium that produces rhamnolipids (RLs), which are utilised in various fields. Although studies have illustrated changes in RLs congeners in response to environmental factors, studies on the influence of temperature on the RLs congeners produced by B. thailandensis E264 are scarce.

    OBJECTIVE: It was hypothesised that RL congeners will be distributed differently at different temperature, which caused the produced RL to have different properties. This brought about the idea of a tailored production of RL for specific application through temperature control. Thus, this study aimed to investigate the distribution of RLs congeners by B. thailandensis E264 in response to different temperatures.

    METHODOLOGY: B. thailandensis E264 was grown at three different temperatures (25 °C, 30 °C, and 37 °C) for nine days and subjected to metabolomic analysis using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QToF-MS).

    RESULTS: The findings indicated that temperature significantly affected the metabolomic distribution of B. thailandensis E264, with mono-rhamno-mono-lipid and mono-rhamno-di-lipid being the predominant metabolites at 37 °C and 30 °C, with relative abundances of 64.1% and 65.3%, respectively. In comparison, di-rhamno-di-lipid was detected at 25 °C with an overall relative abundance of 77.7%.

    CONCLUSION: This investigation showed that changing the cultivation temperature of the non-pathogenic B. thailandensis E264 produces diverse rhamnolipid congeners, which could enable the targeted synthesis of specific RLs for various applications and increase the market value of biosurfactants.

    Matched MeSH terms: Chromatography, Liquid/methods; Mass Spectrometry/methods
  13. Fulltext Investigation of a novel common subexpression elimination method for low power and area efficient DCT architecture
    Siddiqui MF, Reza AW, Kanesan J, Ramiah H
    ScientificWorldJournal, 2014;2014:620868.
    PMID: 25133249 DOI: 10.1155/2014/620868
    A wide interest has been observed to find a low power and area efficient hardware design of discrete cosine transform (DCT) algorithm. This research work proposed a novel Common Subexpression Elimination (CSE) based pipelined architecture for DCT, aimed at reproducing the cost metrics of power and area while maintaining high speed and accuracy in DCT applications. The proposed design combines the techniques of Canonical Signed Digit (CSD) representation and CSE to implement the multiplier-less method for fixed constant multiplication of DCT coefficients. Furthermore, symmetry in the DCT coefficient matrix is used with CSE to further decrease the number of arithmetic operations. This architecture needs a single-port memory to feed the inputs instead of multiport memory, which leads to reduction of the hardware cost and area. From the analysis of experimental results and performance comparisons, it is observed that the proposed scheme uses minimum logic utilizing mere 340 slices and 22 adders. Moreover, this design meets the real time constraints of different video/image coders and peak-signal-to-noise-ratio (PSNR) requirements. Furthermore, the proposed technique has significant advantages over recent well-known methods along with accuracy in terms of power reduction, silicon area usage, and maximum operating frequency by 41%, 15%, and 15%, respectively.
    Matched MeSH terms: Photography/methods; Video Recording/methods; Data Compression/methods*
  14. Compression of patient monitoring video using motion segmentation technique
    Shyamsunder R, Eswaran C, Sriraam N
    J Med Syst, 2007 Apr;31(2):109-16.
    PMID: 17489503
    The volume of patient monitoring video acquired in hospitals is very huge and hence there is a need for better compression of the same for effective storage and transmission. This paper presents a new motion segmentation technique, which improves the compression of patient monitoring video. The proposed motion segmentation technique makes use of a binary mask, which is obtained by thresholding the standard deviation values of the pixels along the temporal axis. Two compression methods, which make use of the proposed motion segmentation technique, are presented. The first method uses MPEG-4 coder and 9/7-biorthogonal wavelet for compressing the moving and stationary portions of the video respectively. The second method uses 5/3-biorthogonal wavelet for compressing both the moving and the stationary portions of the video. The performances of these compression algorithms are evaluated in terms of PSNR and bitrate. From the experimental results, it is found that the proposed motion technique improves the performance of the MPEG-4 coder. Among the two compression methods presented, the MPEG-4 based method performs better for bitrates less than 767 Kbps whereas for bitrates above 767 Kbps the performance of the wavelet based method is found superior.
    Matched MeSH terms: Monitoring, Physiologic/methods*; Videotape Recording/methods*; Data Compression/methods*
  15. Improving diagnostic quality of MR images through controlled lossy compression using SPIHT
    Choong MK, Logeswaran R, Bister M
    J Med Syst, 2006 Jun;30(3):139-43.
    PMID: 16848126
    This paper attempts to improve the diagnostic quality of magnetic resonance (MR) images through application of lossy compression as a noise-reducing filter. The amount of imaging noise present in MR images is compared with the amount of noise introduced by the compression, with particular attention given to the situation where the compression noise is a fraction of the imaging noise. A popular wavelet-based algorithm with good performance, Set Partitioning in Hierarchical Trees (SPIHT), was employed for the lossy compression. Tests were conducted with a number of MR patient images and corresponding phantom images. Different plausible ratios between imaging noise and compression noise (ICR) were considered, and the achievable compression gain through the controlled lossy compression was evaluated. Preliminary results show that at certain ICR's, it becomes virtually impossible to distinguish between the original and compressed-decompressed image. Radiologists presented with a blind test, in certain cases, showed preference to the compressed image rather than the original uncompressed ones, indicating that under controlled circumstances, lossy image compression can be used to improve the diagnostic quality of the MR images.
    Matched MeSH terms: Magnetic Resonance Imaging/methods*; Radiology/methods*; Data Compression/methods*
  16. The rapid-response: a break during lecture
    Rao M
    Adv Physiol Educ, 2006 Jun;30(2):95.
    PMID: 16709743
    Matched MeSH terms: Education, Medical/methods*; Educational Measurement/methods*; Teaching/methods*
  17. Fulltext Single Cell Electrical Characterization Techniques
    Mansor MA, Ahmad MR
    Int J Mol Sci, 2015;16(6):12686-712.
    PMID: 26053399 DOI: 10.3390/ijms160612686
    Electrical properties of living cells have been proven to play significant roles in understanding of various biological activities including disease progression both at the cellular and molecular levels. Since two decades ago, many researchers have developed tools to analyze the cell's electrical states especially in single cell analysis (SCA). In depth analysis and more fully described activities of cell differentiation and cancer can only be accomplished with single cell analysis. This growing interest was supported by the emergence of various microfluidic techniques to fulfill high precisions screening, reduced equipment cost and low analysis time for characterization of the single cell's electrical properties, as compared to classical bulky technique. This paper presents a historical review of single cell electrical properties analysis development from classical techniques to recent advances in microfluidic techniques. Technical details of the different microfluidic techniques are highlighted, and the advantages and limitations of various microfluidic devices are discussed.
    Matched MeSH terms: Flow Cytometry/methods*; Microfluidics/methods*; Single-Cell Analysis/methods*
  18. An intelligent tele-healthcare environment offering person-centric and wellness-maintenance services
    Abidi SS
    J Med Syst, 2001 Jun;25(3):147-65.
    PMID: 11433545
    Worldwide healthcare delivery trends are undergoing a subtle paradigm shift--patient centered services as opposed to provider centered services and wellness maintenance as opposed to illness management. In this paper we present a Tele-Healthcare project TIDE--Tele-Healthcare Information and Diagnostic Environment. TIDE manifests an 'intelligent' healthcare environment that aims to ensure lifelong coverage of person-specific health maintenance decision-support services--i.e., both wellness maintenance and illness management services--ubiquitously available via the Internet/WWW. Taking on an all-encompassing health maintenance role--spanning from wellness to illness issues--the functionality of TIDE involves the generation and delivery of (a) Personalized, Pro-active, Persistent, Perpetual, and Present wellness maintenance services, and (b) remote diagnostic services for managing noncritical illnesses. Technically, TIDE is an amalgamation of diverse computer technologies--Artificial Intelligence, Internet, Multimedia, Databases, and Medical Informatics--to implement a sophisticated healthcare delivery infostructure.
    Matched MeSH terms: Health Promotion/methods*; Telemedicine/methods*; Patient-Centered Care/methods*
  19. ONSD monitoring under anesthesia for middle ear surgery
    Suresh V, Magoon R
    J Anesth, 2024 Aug;38(4):565-566.
    PMID: 37889341 DOI: 10.1007/s00540-023-03274-5
    Matched MeSH terms: Anesthesia/methods; Otologic Surgical Procedures/methods; Monitoring, Intraoperative/methods
  20. Fulltext Droplet Velocity Measurement Based on Dielectric Layer Thickness Variation Using Digital Microfluidic Devices
    Zulkepli SNIS, Hamid NH, Shukla V
    Biosensors (Basel), 2018 May 08;8(2).
    PMID: 29738428 DOI: 10.3390/bios8020045
    In recent years, the number of interdisciplinary research works related to the development of miniaturized systems with integrated chemical and biological analyses is increasing. Digital microfluidic biochips (DMFBs) are one kind of miniaturized systems designed for conducting inexpensive, fast, convenient and reliable biochemical assay procedures focusing on basic scientific research and medical diagnostics. The role of a dielectric layer in the digital microfluidic biochips is prominent as it helps in actuating microliter droplets based on the electrowetting-on-dielectric (EWOD) technique. The advantages of using three different material layers of dielectric such as parafilm, polytetrafluoroethylene (PTFE) and ethylene tetrafluoroethylene (ETFE) were reported in the current work. A simple fabrication process of a digital microfluidic device was performed and good results were obtained. The threshold of the actuation voltage was determined for all dielectric materials of varying thicknesses. Additionally, the OpenDrop device was tested by utilizing a single-plate system to transport microliter droplets for a bioassay operation. With the newly proposed fabrication methods, these dielectric materials showed changes in contact angle and droplet velocity when the actuation voltage was applied. The threshold actuation voltage for the dielectric layers of 10⁻13 μm was 190 V for the open plate DMFBs.
    Matched MeSH terms: Microfluidics/methods*; Microfluidic Analytical Techniques/methods*; Electrowetting/methods*
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links