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1.
Front Nutr ; 10: 1059078, 2023.
Article in English | MEDLINE | ID: mdl-37275635

ABSTRACT

Introduction: During the 20th century, the worldwide genetic diversity of wheat was sharply eroded by continual selection for high yields and industry demands for particular standardized qualities. A collection of Israeli and Palestinian landraces (IPLR) was established to represent genetic diversity, accumulated for ten millennia under diverse environments, which was mostly lost in this transition. As our long-term goal is to study this pre- Green Revolution genetic reservoir, herein we focus on its flour and bread quality and sensorial attributes. Methods: Initially, a database was built for the entire IPLR collection (n=901) holding both Triticum durum (durum wheat) and T. aestivum (bread wheat) which included genetic and phenotypic characterization of agronomic traits, grain and flour quality. Then, a representative subset of the IPLR was selected and compared to modern varieties for dough quality, rheology, aroma and taste using both whole and refined flours and breads. The sensory panel used 40 subjects who evaluated common protocol or sourdough breads made by four artisan bakers. Results: Results show modern durum cultivar C-9 had superior rheological properties (gluten index, elasticity, dough development time) as compared with landraces, while bread landrace 'Diar Alla' was markedly preferable for baking in relation to the modern cultivar Gadish. Baking tests and subsequent sensory evaluation clearly demonstrated a preference toward refined breads, apart from whole breads prepared using sourdough starters. In bread wheat, loaves baked using landrace flour were scored higher in several quality parameters, whereas in durum lines, the opposite trend was evident. Loaves baked from landraces 'Diar Alla' and to a lesser extent 'Hittia Soada' presented a markedly different aroma from the control loaves prepared from modern flours, both in terms of overall compositions and individual compounds, including classes such as pyranones, pyrazines, furans and pyrroles (maltol). Modern lines, on the other hand, were consistently richer in terpenes and phenylpropanoids. Further analysis demonstrated a significant association between specific aroma classes and sensory attributes scored by panelists. Discussion: The findings of the study may help advance new niches in the local wheat market aimed at health and nutrition including adapting durum varieties to the bread market and developing flavor-enhanced wholemeal breads.

2.
Opt Lett ; 47(20): 5429-5432, 2022 Oct 15.
Article in English | MEDLINE | ID: mdl-36240381

ABSTRACT

Simultaneous rotational and vibrational temperatures are measured in an N2 plasma with rotational coherent anti-Stokes Raman scattering (CARS) resolved with a virtually imaged phased array (VIPA)-based spectrometer. A VIPA spectrally separates rotational transitions for each vibrational state, allowing vibrational populations to be directly measured. VIPA-CARS is shown to provide more accurate measurements of non-equilibrium temperatures than grating-resolved rotational CARS. The general characteristics, limitations, and potential uses of VIPA-CARS are discussed.

3.
Sci Rep ; 11(1): 11549, 2021 06 15.
Article in English | MEDLINE | ID: mdl-34131158

ABSTRACT

We show that malicious COVID-19 content, including racism, disinformation, and misinformation, exploits the multiverse of online hate to spread quickly beyond the control of any individual social media platform. We provide a first mapping of the online hate network across six major social media platforms. We demonstrate how malicious content can travel across this network in ways that subvert platform moderation efforts. Machine learning topic analysis shows quantitatively how online hate communities are sharpening COVID-19 as a weapon, with topics evolving rapidly and content becoming increasingly coherent. Based on mathematical modeling, we provide predictions of how changes to content moderation policies can slow the spread of malicious content.

4.
S Afr Med J ; 110(7): 667-670, 2020 Jul 07.
Article in English | MEDLINE | ID: mdl-32880345

ABSTRACT

BACKGROUND: Trauma in pregnancy poses a unique challenge to clinicians. Literature on this topic is limited in South Africa (SA). OBJECTIVES: To review our institution's experience with the management of trauma in pregnancy in a developing-world setting. METHODS: This study was based at Grey's Hospital, Pietermaritzburg, SA. All pregnant patients who were admitted to our institution following trauma between December 2012 and December 2018 were identified from the Hybrid Electronic Medical Registry (HEMR). RESULTS: During the 6-year study period, 2 990 female patients were admitted by the Pietermaritzburg Metropolitan Trauma Service (PMTS), of whom 89 were pregnant. The mean age of these patients was 25.64 (range 17 - 43) years. The mechanism of injury was road traffic crash (RTC) in 39, stab wounds (SW) in 19, assault other than SW or gunshot wounds (GSW) in 19, GSW in 8, snake bite in 5, impalement in 1, dog bite in 1, hanging in 1, sexual assault in 1 and a single case of a patient being hit by a falling object. A subset of patients sustained >1 mechanism of injury. Thirty patients were managed operatively. The mean time of gestation was 19.16 (5 - 36) weeks. Three patients died, and there were 16 fetal deaths (including 3 lost after the mother's death). Forty-five fetuses were recorded as surviving at discharge, while 25 fetal outcomes were not specifically recorded. There were 2 threatened miscarriages and/or patients with vaginal bleeding, 1 positive pregnancy test with no recorded outcome and no premature births as a result of trauma. CONCLUSIONS: Trauma in pregnancy is relatively uncommon and mostly due to a RTC or deliberately inflicted trauma. Fetal outcome is largely dependent on the severity of the maternal injury, with injuries requiring laparotomy leading to a high fetal mortality rate.


Subject(s)
Pregnancy Complications/epidemiology , Wounds and Injuries/epidemiology , Adolescent , Adult , Age Distribution , Female , Fetal Death , Humans , Pregnancy , Pregnancy Complications/surgery , South Africa/epidemiology , Surgical Procedures, Operative/statistics & numerical data , Trauma Centers , Wounds and Injuries/surgery , Young Adult
5.
Allergy ; 70(6): 609-15, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25736171

ABSTRACT

The global allergy community strongly believes that the 11th revision of the International Classification of Diseases (ICD-11) offers a unique opportunity to improve the classification and coding of hypersensitivity/allergic diseases via inclusion of a specific chapter dedicated to this disease area to facilitate epidemiological studies, as well as to evaluate the true size of the allergy epidemic. In this context, an international collaboration has decided to revise the classification of hypersensitivity/allergic diseases and to validate it for ICD-11 by crowdsourcing the allergist community. After careful comparison between ICD-10 and 11 beta phase linearization codes, we identified gaps and trade-offs allowing us to construct a classification proposal, which was sent to the European Academy of Allergy and Clinical Immunology (EAACI) sections, interest groups, executive committee as well as the World Allergy Organization (WAO), and American Academy of Allergy Asthma and Immunology (AAAAI) leaderships. The crowdsourcing process produced comments from 50 of 171 members contacted by e-mail. The classification proposal has also been discussed at face-to-face meetings with experts of EAACI sections and interest groups and presented in a number of business meetings during the 2014 EAACI annual congress in Copenhagen. As a result, a high-level complex structure of classification for hypersensitivity/allergic diseases has been constructed. The model proposed has been presented to the WHO groups in charge of the ICD revision. The international collaboration of allergy experts appreciates bilateral discussion and aims to get endorsement of their proposals for the final ICD-11.


Subject(s)
Allergy and Immunology , Consensus , Crowdsourcing , Hypersensitivity/classification , International Classification of Diseases , Humans
6.
Ultraschall Med ; 34(1): 11-29, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23129518

ABSTRACT

Initially, a set of guidelines for the use of ultrasound contrast agents was published in 2004 dealing only with liver applications. A second edition of the guidelines in 2008 reflected changes in the available contrast agents and updated the guidelines for the liver, as well as implementing some non-liver applications. Time has moved on, and the need for international guidelines on the use of CEUS in the liver has become apparent. The present document describes the third iteration of recommendations for the hepatic use of contrast enhanced ultrasound (CEUS) using contrast specific imaging techniques. This joint WFUMB-EFSUMB initiative has implicated experts from major leading ultrasound societies worldwide. These liver CEUS guidelines are simultaneously published in the official journals of both organizing federations (i.e., Ultrasound in Medicine and Biology for WFUMB and Ultraschall in der Medizin/European Journal of Ultrasound for EFSUMB). These guidelines and recommendations provide general advice on the use of all currently clinically available ultrasound contrast agents (UCA). They are intended to create standard protocols for the use and administration of UCA in liver applications on an international basis and improve the management of patients worldwide.


Subject(s)
Carcinoma, Hepatocellular/ultrastructure , Contrast Media/administration & dosage , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Liver Diseases/diagnostic imaging , Liver Neoplasms/diagnostic imaging , Liver/diagnostic imaging , Anaphylaxis/chemically induced , Anaphylaxis/mortality , Biopsy, Needle/methods , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/surgery , Cell Transformation, Neoplastic/pathology , Contraindications , Contrast Media/adverse effects , Diagnosis, Differential , Drug Hypersensitivity/etiology , Drug Hypersensitivity/mortality , Drug Interactions , Ferric Compounds/adverse effects , Fluorocarbons/adverse effects , Humans , Iron/adverse effects , Liver/pathology , Liver/surgery , Liver Cirrhosis/diagnostic imaging , Liver Cirrhosis/pathology , Liver Diseases/pathology , Liver Diseases/surgery , Liver Neoplasms/pathology , Liver Neoplasms/secondary , Liver Neoplasms/surgery , Liver Transplantation/pathology , Oxides/adverse effects , Phospholipids/adverse effects , Risk Factors , Sulfur Hexafluoride/adverse effects , Ultrasonography, Doppler/methods , Ultrasonography, Interventional/methods
8.
Nano Lett ; 10(11): 4727-31, 2010 Nov 10.
Article in English | MEDLINE | ID: mdl-20964282

ABSTRACT

Rapid, chip-scale, and cost-effective single particle detection of biological agents is of great importance to human health and national security. We report real-time, high-throughput detection and sizing of individual, low-index polystyrene nanoparticles and H1N1 virus. Our widefield, common path interferometer detects nanoparticles and viruses over a very large sensing area, orders of magnitude larger than competing techniques. We demonstrate nanoparticle detection and sizing down to 70 nm in diameter. We clearly size discriminate nanoparticles with diameters of 70, 100, 150, and 200 nm. We also demonstrate detection and size characterization of hundreds of individual H1N1 viruses in a single experiment.


Subject(s)
Biosensing Techniques/instrumentation , Influenza A Virus, H1N1 Subtype/isolation & purification , Influenza A Virus, H1N1 Subtype/ultrastructure , Interferometry/instrumentation , Nanostructures/ultrastructure , Particle Size , Equipment Design , Equipment Failure Analysis , Nanoparticles
9.
Opt Lett ; 34(8): 1261-3, 2009 Apr 15.
Article in English | MEDLINE | ID: mdl-19370137

ABSTRACT

We investigate the effect of an annular pupil-plane aperture in confocal imaging while using an NA increasing lens. We show that focal spot shape is highly sensitive to both polarization and angular spectrum of the incoming light. We demonstrate a lateral spatial resolution of 145 nm (lambda(0)/9) in the direction perpendicular to the polarization direction.

10.
Article in English | MEDLINE | ID: mdl-19163247

ABSTRACT

We present biological imaging and sensing methods based on optical resonance and interference. In fluorescence microscopy, our nanoscale imaging capability sheds light onto conformational changes of DNA, DNA-protein complexes and polymer coatings on a solid surface. Interference measurements on a layered substrate yield a label-free sensing platform for protein binding in a high-throughput micro-array format.


Subject(s)
Microscopy, Fluorescence/instrumentation , Microscopy, Fluorescence/methods , Optics and Photonics/instrumentation , Optics and Photonics/methods , Protein Array Analysis/instrumentation , Protein Array Analysis/methods , Proteins/chemistry , Animals , Biosensing Techniques , Electrochemistry/instrumentation , Fluorescence , Fluorescent Dyes , Humans , Nucleic Acid Hybridization
11.
Nano Lett ; 7(9): 2892-6, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17691853

ABSTRACT

Through the utilization of index-matched GaAs immersion lens techniques, we demonstrate a record extinction (12%) of a far-field focused laser beam by a single InAs/GaAs quantum dot. This contrast level enables us to report for the first time resonant laser transmission spectroscopy on a single InAs/GaAs quantum dot without the need for phase-sensitive lock-in detection.


Subject(s)
Arsenicals/chemistry , Arsenicals/radiation effects , Gallium/chemistry , Gallium/radiation effects , Indium/chemistry , Indium/radiation effects , Lasers , Nanotechnology/methods , Quantum Dots , Materials Testing
12.
Phys Rev Lett ; 98(3): 037404, 2007 Jan 19.
Article in English | MEDLINE | ID: mdl-17358726

ABSTRACT

We report on an optical method to directly measure electron-phonon coupling in carbon nanotubes by correlating the first and second harmonic of the resonant Raman excitation profile. The method is applicable to 1D and 0D systems and is not limited to materials that exhibit photoluminescence. Experimental results for electron-phonon coupling with the radial breathing mode in 5 different nanotubes show coupling strengths from 3-11 meV. The results are in good agreement with the chirality and diameter dependence of the e-ph coupling calculated by Goupalov et al.

13.
Opt Lett ; 32(8): 970-2, 2007 Apr 15.
Article in English | MEDLINE | ID: mdl-17375171

ABSTRACT

We theoretically study the problem of detecting dipole radiation in a fiber-based confocal microscope of high numerical aperture. By using a single-mode fiber, in contrast to a hard-stop pinhole aperture, the detector becomes sensitive to the phase of the field amplitude. We find that the maximum in collection efficiency of the dipole radiation does not coincide with the optimum resolution for the light-gathering instrument. The derived expressions are important for analyzing fiber-based confocal microscope performance in fluorescence and spectroscopic studies of single molecules and/or quantum dots.

14.
Phys Rev Lett ; 96(12): 127403, 2006 Mar 31.
Article in English | MEDLINE | ID: mdl-16605957

ABSTRACT

Tunable Raman spectroscopy is used to measure the optical transition energies Eii of individual single wall carbon nanotubes. Eii is observed to shift down in energy by as much as 50 meV, from -160 to 300 degrees C, in contrast with previous measurements performed on nanotubes in alternate environments, which show upshifts and downshifts in Eii with temperature. We determine that electron-phonon coupling explains our experimental observations of nanotubes suspended in air, neglecting thermal expansion. In contrast, for nanotubes in surfactant or in bundles, thermal expansion of the nanotubes' environment exerts a nonisotropic pressure on the nanotube that dominates over the effect of electron-phonon coupling.

15.
Phys Med Biol ; 50(10): 2241-8, 2005 May 21.
Article in English | MEDLINE | ID: mdl-15876664

ABSTRACT

The compound probability density function (pdf) is investigated for the ability of its parameters to classify masses in ultrasonic B scan breast images. Results of 198 images (29 malignant and 70 benign cases and two images per case) are reported and compared to the classification performance reported by us earlier in this journal. A new parameter, the speckle factor, calculated from the parameters of the compound pdf was explored to separate benign and malignant masses. The receiver operating characteristic curve for the parameter resulted in an A(z) value of 0.852. This parameter was combined with one of the parameters from our previous work, namely the ratio of the K distribution parameter at the site and away from the site. This combined parameter resulted in an A(z) value of 0.955. In conclusion, the parameters of the K distribution and the compound pdf may be useful in the classification of breast masses. These parameters can be calculated in an automated fashion. It should be possible to combine the results of the ultrasonic image analysis with those of traditional mammography, thereby increasing the accuracy of breast cancer diagnosis.


Subject(s)
Algorithms , Artificial Intelligence , Breast Neoplasms/diagnostic imaging , Image Interpretation, Computer-Assisted/methods , Models, Biological , Breast Neoplasms/classification , Cluster Analysis , Female , Humans , Models, Statistical , Reproducibility of Results , Sensitivity and Specificity , Statistical Distributions , Ultrasonography
16.
J Nanosci Nanotechnol ; 5(2): 209-28, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15853139

ABSTRACT

Several techniques were recently reported for the bulk separation of metallic (M) and semiconducting (S) single wall carbon nanotubes (SWNTs), using optical absorption and resonance Raman spectroscopy (RRS) as a proof of the separation. In the present work, we develop a method for the quantitative evaluation of the M to S separation ratio, and also for the SWNT diameter selectivity of the separation process, based on RRS. The relative changes in the integrated intensities of the radial-breathing mode (RBM) features, with respect to the starting material, yield the diameter probability distribution functions for M and S SWNTs in the separated fractions, accounting for the different resonance conditions of individual SWNTs, while the diameter distribution of the starting material is obtained following the fitting procedure developed by Kuzmany and coworkers. Features other than the RBM are generally less effective for characterization of the separation process for SWNTs.


Subject(s)
Metals/chemistry , Nanotubes, Carbon/chemistry , Spectrum Analysis, Raman/methods , Nanotechnology/methods
17.
Phys Rev Lett ; 93(16): 167401, 2004 Oct 15.
Article in English | MEDLINE | ID: mdl-15525030

ABSTRACT

Raman spectroscopy is used to measure the strain in individual single-wall carbon nanotubes, strained by manipulation with an atomic-force-microscope tip. Under strains varying from 0.06%-1.65%, the in-plane vibrational mode frequencies are lowered by as much as 1.5% (40 cm(-1)), while the radial breathing mode (RBM) remains unchanged. The RBM Stokes/anti-Stokes intensity ratio remains unchanged under strain. The elasticity of these strain deformations is demonstrated as the down-shifted Raman modes resume their prestrain frequencies after a nanotube is broken under excessive strain.

18.
Phys Rev Lett ; 90(10): 107403, 2003 Mar 14.
Article in English | MEDLINE | ID: mdl-12689031

ABSTRACT

Resonance Raman studies on single wall carbon nanotubes (SWNTs) show that resonance with cross polarized light, i.e., with the E(mu,mu+/-1) van Hove singularities in the joint density of states needs to be taken into account when analyzing the Raman and optical absorption spectra from isolated SWNTs. This study is performed by analyzing the polarization, laser energy, and diameter dependence of two Raman features, the tangential modes (G band) and a second-order mode (G' band), at the isolated SWNT level.

19.
Ultrasound Med Biol ; 28(10): 1295-300, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12467856

ABSTRACT

Classification of masses in ultrasonic B-mode images of the breast tissue using "normalized" parameters of the Nakagami distribution was recently investigated. The technique, however, did not yield performances that were comparable to those of an experienced radiologist, and utilized only a single image for tissue characterization. Because radiologists commonly use two to four images of a mass for characterization, a similar procedure is developed here. A simple summation of the normalized Nakagami parameters from two different images of a mass is utilized for classification as benign or malignant. The performance of the normalized Nakagami parameters before and after the summation has been carried out through a receiver operating characteristic (ROC) study. The bootstrap procedure has been utilized to compute the mean and SD of the ROC area, A(z), obtained for each parameter. It has been observed that combining normalized Nakagami parameters from two images of the mass may help to improve classification performance over that from utilizing the parameters of just a single image. The performance of this automated parameter-based approach appears to match that of a trained radiologist.


Subject(s)
Algorithms , Breast Neoplasms/diagnostic imaging , Ultrasonography, Mammary , Breast Neoplasms/classification , Diagnosis, Differential , Female , Humans , Image Processing, Computer-Assisted , ROC Curve , Sensitivity and Specificity
20.
Med Phys ; 29(9): 1968-73, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12349916

ABSTRACT

Frequency compounding was recently investigated for computer aided classification of masses in ultrasonic B-mode images as benign or malignant. The classification was performed using the normalized parameters of the Nakagami distribution at a single region of interest at the site of the mass. A combination of normalized Nakagami parameters from two different images of a mass was undertaken to improve the performance of classification. Receiver operating characteristic (ROC) analysis showed that such an approach resulted in an area of 0.83 under the ROC curve. The aim of the work described in this paper is to see whether a feature describing the characteristic of the boundary can be extracted and combined with the Nakagami parameter to further improve the performance of classification. The combination of the features has been performed using a weighted summation. Results indicate a 10% improvement in specificity at a sensitivity of 96% after combining the information at the site and at the boundary. Moreover, the technique requires minimal clinical intervention and has a performance that reaches that of the trained radiologist. It is hence suggested that this technique may be utilized in practice to characterize breast masses.


Subject(s)
Breast Neoplasms/classification , Breast Neoplasms/diagnostic imaging , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Ultrasonography, Mammary/methods , Humans , Models, Biological , Models, Statistical , Quality Control , Reproducibility of Results , Sensitivity and Specificity
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