Wavefront analysis: An additional tool for detection of keratoconus

2017 ◽  
Vol 55 (3) ◽  
pp. 177
Author(s):  
Sujatha Mohan ◽  
Mohan Rajan ◽  
Siddhartha Singh ◽  
Atul Bhirud ◽  
Sriram Annavajjhala
Keyword(s):  
Wavefront Analysis ◽  
Additional Tool

The Potentials of Scanning Microscopy

1968 ◽  
Vol 26 ◽  
pp. 352-353
Author(s):  
A. V. Crewe
Keyword(s):  
Salient Feature ◽  
Secondary Emission ◽  
Resolving Power ◽  
X Rays ◽  
Scanning Microscope ◽  
Forming Process ◽  
Additional Tool ◽  
Detection Systems ◽  
Conventional Microscope ◽  
Present Information

If the resolving power of a scanning electron microscope can be improved until it is comparable to that of a conventional microscope, it would serve as a valuable additional tool in many investigations.The salient feature of scanning microscopes is that the image-forming process takes place before the electrons strike the specimen. This means that several different detection systems can be employed in order to present information about the specimen. In our own particular work we have concentrated on the use of energy loss information in the beam which is transmitted through the specimen, but there are also numerous other possibilities (such as secondary emission, generation of X-rays, and cathode luminescence).Another difference between the pictures one would obtain from the scanning microscope and those obtained from a conventional microscope is that the diffraction phenomena are totally different. The only diffraction phenomena which would be seen in the scanning microscope are those which exist in the beam itself, and not those produced by the specimen.

Ч. АЙТМАТОВДУН «ТООЛОР КУЛАГАНДА» РОМАНЫНДАГЫ ПЕЙЗАЖДЫК СҮРӨТТӨӨЛӨР

2020 ◽  
pp. 92-94
Author(s):  
Н. Алтыкеева ◽  
Б. Ниясалиева
Keyword(s):  
Full Moon ◽  
The Novel ◽  
Additional Tool ◽  
The Sublime ◽  
The World ◽  
State Of Mind ◽  
Inner World ◽  
Aesthetic Values

Аннотация. Макалада романдын мазмунунан орун алган пейзаждык сүрөттөөлөр талкууланат. Пейзаждык сүрөттөөлөр чыгарманын көркөмдүүлүгүн, эстетикалык баалуулугун арттыруу менен катар эле каармандардын образын тереңден ачып берүүдө, окуялардын өнүгүп-өсүшү жана алдыда боло турган окуялар тууралуу окурманга маалымат берүүдө кошумча каражат катары колдонулат. Жазуучу романда пейзаждык сүрөттөөлөрдү өтө кылдат колдонгону байкалат. Алсак, тоо адамдагы улуулук жана бийиктикти айгинелейт, толукшуган ай жан- дүйнөнүн бөксөрбөй толуп турушун көрсөтөт, ачык асмандын алай-дүлөй түшкөн көрүнүшкө айланышы - каармандын ички сезими, уйгу-туйгу ойлонуусу, жан дүйнөсүнүн бурганак болушун ачып көрсөтүүдө маанилүү болсо, чабалекейлердин тынымсыз учуп чабалакташы, жан алакетке түшүп чыйпылдашы – алдыда боло турган кырсыктуу окуя тууралуу кабар берсе, согуштун апааты жашыл шибердин, бак-дарактардын күлгө айланышы, чымчык-куштардын күздү күтпөй кайдадыр учуп кетип жатышы менен түшүндүрүлөт. Tүйүндүү сөздөр: пейзаж. роман, идея, легенда, эпилог, каарман, негизги окуялар. Аннотация. В статье дается пейзажное описание. Пейзажное описание используется в произведении как дополнительное средство эстетических ценностей и помогает раскрыть образы героев, и действия произведения. Писатель в романе тонко использует пейзажное описание. Например горы возвышенное и самое ценное в человеке, а полная луна – счастливое душевное состояние человека, а превращение безоблачного неба в бущующий вид – указывает, как неспокойно в душе главного героя, его беспокойные мысли, как бушует его внутренний мир, а ласточки неспокойно летающие, предвещают несчастье, птицы улетающие раньше времени, превращение зелёной травы, деревьев в пепел предвещают ужасы войны. Ключевые слова: пейзаж. роман, идея, легенда, эпилог, герой, главное событие Annotation. The article discusses the landscape description. The landscape description is used in the work as an additional tool for aesthetic values and helps to reveal the images of heroes, and in the development of the action of the work/ The writer in the novel subtly uses the landscape description. The mountains are the sublime and the most valuable in a person, and the full moon is a happy state of mind of a person, and the transformation of a cloudless sky into a raging view indicates how restless the soul of the protagonist is, his restless thoughts. How his inner world is raging, and the swallows are restlessly flying, foreshadow the misfortune, the birds flying away ahead of time, the transformation of green grass, trees in the forehead the horrors of war. This article describes the idea of the story "Do not kill" which is given instead of the epilogue in the novel "When the mountains fall" which was written by Ch.Aitmatov. It considers the role of a story that calls to live in peace and to end wars that are occurring in the world. Keywords: Landscapе, novel, idea, legend, epilogue, hero, main event.

scholarly journals Biology and Physics of Heterochromatin-Like Domains/Complexes

Cells ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1881
Author(s):  
Prim B. Singh ◽  
Stepan N. Belyakin ◽  
Petr P. Laktionov
Keyword(s):  
Phase Separation ◽  
Fission Yeast ◽  
Thermodynamic Description ◽  
Dynamic Structure ◽  
Vertebrate Development ◽  
Type Region ◽  
Additional Tool ◽  
3D Genome ◽  
Chromatin Template ◽  
Cis And Trans

The hallmarks of constitutive heterochromatin, HP1 and H3K9me2/3, assemble heterochromatin-like domains/complexes outside canonical constitutively heterochromatic territories where they regulate chromatin template-dependent processes. Domains are more than 100 kb in size; complexes less than 100 kb. They are present in the genomes of organisms ranging from fission yeast to human, with an expansion in size and number in mammals. Some of the likely functions of domains/complexes include silencing of the donor mating type region in fission yeast, preservation of DNA methylation at imprinted germline differentially methylated regions (gDMRs) and regulation of the phylotypic progression during vertebrate development. Far cis- and trans-contacts between micro-phase separated domains/complexes in mammalian nuclei contribute to the emergence of epigenetic compartmental domains (ECDs) detected in Hi-C maps. A thermodynamic description of micro-phase separation of heterochromatin-like domains/complexes may require a gestalt shift away from the monomer as the “unit of incompatibility” that determines the sign and magnitude of the Flory–Huggins parameter, χ. Instead, a more dynamic structure, the oligo-nucleosomal “clutch”, consisting of between 2 and 10 nucleosomes is both the long sought-after secondary structure of chromatin and its unit of incompatibility. Based on this assumption we present a simple theoretical framework that enables an estimation of χ for domains/complexes flanked by euchromatin and thereby an indication of their tendency to phase separate. The degree of phase separation is specified by χN, where N is the number of “clutches” in a domain/complex. Our approach could provide an additional tool for understanding the biophysics of the 3D genome.

Energy-Dispersive X-ray Fluorescence Analysis as a Rapid Method for Identifying Tephras

1983 ◽  
Vol 19 (2) ◽  
pp. 201-211 ◽  
Author(s):  
A. B. Cormie ◽  
D. E. Nelson
Keyword(s):  
Reliable Method ◽  
Fluorescence Analysis ◽  
Energy Dispersive ◽  
Bulk Glass ◽  
X Ray ◽  
Additional Tool ◽  
White River ◽  
Routine Identification ◽  
Weathering Effects ◽  
Mount St Helens

AbstractThe use of energy-dispersive X-ray fluorescence analysis (XES) for the routine identification of three tephras (Mazama, Bridge River, Mount St. Helens Yn) commonly found in archeological sites in British Columbia has been investigated. Researchers have often assumed that chemical analysis of bulk samples of glass separates would be hampered by contamination and weathering effects. Our results indicate that XES of bulk glass separates provides a very reliable method for rapidly identifying the three tephras in question, even with a very simple sample preparation. This should enable persons not skilled in geology or in tephrochronology to collect and to identify samples of these tephras. Finally, as a part of the study, similar measurements were made on the separated glass portions of these three tephras and of three others (Glacier Peak B and G, White River) from northwest North America. The results suggest that this method may provide tephrochronologists with a useful additional tool for studying tephras in other regions.

scholarly journals The Global Limb Anatomic Staging System (GLASS) for CLTI: Improving Inter-Observer Agreement

2021 ◽  
Vol 10 (16) ◽  
pp. 3454
Author(s):  
Joep G. J. Wijnand ◽  
Devin Zarkowsky ◽  
Bian Wu ◽  
Steven T. W. van Haelst ◽  
Evert-Jan P. A. Vonken ◽  
...  
Keyword(s):  
Staging System ◽  
The United States ◽  
Lessons Learned ◽  
Observer Agreement ◽  
Lesion Length ◽  
Solid Base ◽  
Stepwise Approach ◽  
Additional Tool ◽  
Atherosclerotic Lesions ◽  
Stenosis Severity

Objective: The 2020 Global Vascular Guidelines aim at improving decision making in Chronic Limb-Threatening Ischemia (CLTI) by providing a framework for evidence-based revascularization. Herein, the Global Limb Anatomic Staging System (GLASS) serves to estimate the chance of success and patency of arterial pathway revascularization based on the extent and distribution of the atherosclerotic lesions. We report the preliminary feasibility results and observer variability of the GLASS. GLASS is a part of the new global guideline and posed as a promising additional tool for EBR strategies to predict the success of lower extremity arterial revascularization. This study reports on the consistency of GLASS scoring to maximize inter-observer agreement and facilitate its application. Methods: GLASS separately scores the femoropopliteal (FP) and infrapopliteal (IP) segment based on stenosis severity, lesion length and the extent of calcification within the target artery pathway (TAP). In our stepwise approach, we used two angiographic datasets. Each following step was based on the lessons learned from the previous step. The primary outcome was inter-observer agreement measured as Cohen’s Kappa, scored by two (step 1 + 2) and four (step 3) blinded and experienced observers, respectively. Steps 1 (n = 139) and 2 (n = 50) were executed within a dataset of a Dutch interventional RCT in CLTI. Step 3 (n = 100) was performed in randomly selected all-comer CLTI patients from two vascular centers in the United States. Results: In step 1, kappa values were 0.346 (FP) and 0.180 (IP). In step 2, applied in the same dataset, the use of other experienced observers and a provided TAP, resulted in similar low kappa values 0.406 (FP) and 0.089 (IP). Subsequently, in step 3, the formation of an altered stepwise approach using component scoring, such as separate scoring of calcification and adding a ruler to the images resulted in kappa values increasing to 0.796 (FP) and 0.730 (IP). Conclusion: This retrospective GLASS validation study revealed low inter-observer agreement for unconditioned scoring. A stepwise component scoring provides acceptable agreement and a solid base for further prospective validation studies to investigate how GLASS relates to treatment outcomes.

scholarly journals Outcome Prediction in Patients with Severe COVID-19 Requiring Extracorporeal Membrane Oxygenation—A Retrospective International Multicenter Study

Membranes ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 170
Author(s):  
Alexander Supady ◽  
Jeff DellaVolpe ◽  
Fabio Silvio Taccone ◽  
Dominik Scharpf ◽  
Matthias Ulmer ◽  
...  
Keyword(s):  
Extracorporeal Membrane Oxygenation ◽  
The United States ◽  
Apache Ii ◽  
Apache Ii Score ◽  
Survival Prediction ◽  
Study Cohort ◽  
Additional Tool ◽  
Saps Ii ◽  
Membrane Oxygenation ◽  
International Multicenter

The role of veno-venous extracorporeal membrane oxygenation therapy (V-V ECMO) in severe COVID-19 acute respiratory distress syndrome (ARDS) is still under debate and conclusive data from large cohorts are scarce. Furthermore, criteria for the selection of patients that benefit most from this highly invasive and resource-demanding therapy are yet to be defined. In this study, we assess survival in an international multicenter cohort of COVID-19 patients treated with V-V ECMO and evaluate the performance of several clinical scores to predict 30-day survival. Methods: This is an investigator-initiated retrospective non-interventional international multicenter registry study (NCT04405973, first registered 28 May 2020). In 127 patients treated with V-V ECMO at 15 centers in Germany, Switzerland, Italy, Belgium, and the United States, we calculated the Sequential Organ Failure Assessment (SOFA) Score, Simplified Acute Physiology Score II (SAPS II), Acute Physiology And Chronic Health Evaluation II (APACHE II) Score, Respiratory Extracorporeal Membrane Oxygenation Survival Prediction (RESP) Score, Predicting Death for Severe ARDS on V‑V ECMO (PRESERVE) Score, and 30-day survival. Results: In our study cohort which enrolled 127 patients, overall 30-day survival was 54%. Median SOFA, SAPS II, APACHE II, RESP, and PRESERVE were 9, 36, 17, 1, and 4, respectively. The prognostic accuracy for all these scores (area under the receiver operating characteristic—AUROC) ranged between 0.548 and 0.605. Conclusions: The use of scores for the prediction of mortality cannot be recommended for treatment decisions in severe COVID-19 ARDS undergoing V-V ECMO; nevertheless, scoring results below or above a specific cut-off value may be considered as an additional tool in the evaluation of prognosis. Survival rates in this cohort of COVID-19 patients treated with V‑V ECMO were slightly lower than those reported in non-COVID-19 ARDS patients treated with V-V ECMO.

Gelatin-Containing Vaccines for Varicella, Zoster, Measles, Mumps, and Rubella Induce Basophil Activation in Patients with Alpha-Gal Syndrome

2021 ◽  
pp. 1-7
Author(s):  
Paul Schmidle ◽  
Jana Mehlich ◽  
Knut Brockow ◽  
Ulf Darsow ◽  
Tilo Biedermann ◽  
...  
Keyword(s):  
Case Reports ◽  
Meat Products ◽  
Live Vaccine ◽  
Basophil Activation ◽  
Type I ◽  
Mmr Vaccine ◽  
Varicella Zoster ◽  
Additional Tool ◽  
Severe Anaphylaxis ◽  
New Type

Background: The alpha-gal syndrome (AGS) describes a new type I allergy entity to the carbohydrate epitope galactose-α-1,3-galactose (alpha-gal), which is mainly found in mammalian food products (e.g., beef, pork, and venison). Apart from meat products, alpha-gal can also be found in products containing gelatin of bovine or porcine origin. Recent case reports pointed to severe anaphylaxis in patients suffering from AGS after vaccination with vaccines containing hydrolyzed gelatin. It was the objective of this study to evaluate if basophil activation tests (BATs) performed with such vaccines were positive in patients with AGS. Methods: BAT was performed with different dilutions of a gelatin-containing measles, mumps, and rubella (MMR) live vaccine; an attenuated varicella (V) vaccine; an attenuated V-zoster (VZ) vaccine; a MMR live vaccine not containing gelatin (non-gelatin MMR vaccine) in 2 patients with confirmed AGS, 2 patients highly suspicious for AGS, and 2 healthy individuals without any previous medical history for allergies. Results: All patients showed strongly positive results for all gelatin-containing vaccines (MMR vaccine, V vaccine, and VZ vaccine). Non-gelatin MMR vaccine was negative. The 2 healthy controls did not show any basophil activation. Conclusions: Gelatin-containing vaccines should be administered with caution or avoided in patients with AGS because of their high potential to activate basophils indicating a risk for anaphylaxis. Also, BAT is a useful additional tool when it comes to screening for potentially high-risk alpha-gal-containing drugs.

scholarly journals Dietary Behaviors and Incident COVID-19 in the UK Biobank

Nutrients ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 2114
Author(s):  
Thanh-Huyen T. Vu ◽  
Kelsey J. Rydland ◽  
Chad J. Achenbach ◽  
Linda Van Horn ◽  
Marilyn C. Cornelis
Keyword(s):  
Dietary Behaviors ◽  
Processed Meat ◽  
Uk Biobank ◽  
Processed Meats ◽  
Additional Tool ◽  
Oily Fish ◽  
Case Rate ◽  
Specific Association ◽  
Socio Demographic Factors ◽  
The Uk

Background: Nutritional status influences immunity but its specific association with susceptibility to COVID-19 remains unclear. We examined the association of specific dietary data and incident COVID-19 in the UK Biobank (UKB). Methods: We considered UKB participants in England with self-reported baseline (2006–2010) data and linked them to Public Health England COVID-19 test results—performed on samples from combined nose/throat swabs, using real time polymerase chain reaction (RT-PCR)—between March and November 2020. Baseline diet factors included breastfed as baby and specific consumption of coffee, tea, oily fish, processed meat, red meat, fruit, and vegetables. Individual COVID-19 exposure was estimated using the UK’s average monthly positive case rate per specific geo-populations. Logistic regression estimated the odds of COVID-19 positivity by diet status adjusting for baseline socio-demographic factors, medical history, and other lifestyle factors. Another model was further adjusted for COVID-19 exposure. Results: Eligible UKB participants (n = 37,988) were 40 to 70 years of age at baseline; 17% tested positive for COVID-19 by SAR-CoV-2 PCR. After multivariable adjustment, the odds (95% CI) of COVID-19 positivity was 0.90 (0.83, 0.96) when consuming 2–3 cups of coffee/day (vs. <1 cup/day), 0.88 (0.80, 0.98) when consuming vegetables in the third quartile of servings/day (vs. lowest quartile), 1.14 (1.01, 1.29) when consuming fourth quartile servings of processed meats (vs. lowest quartile), and 0.91 (0.85, 0.98) when having been breastfed (vs not breastfed). Associations were attenuated when further adjusted for COVID-19 exposure, but patterns of associations remained. Conclusions: In the UK Biobank, consumption of coffee, vegetables, and being breastfed as a baby were favorably associated with incident COVID-19; intake of processed meat was adversely associated. Although these findings warrant independent confirmation, adherence to certain dietary behaviors may be an additional tool to existing COVID-19 protection guidelines to limit the spread of this virus.

scholarly journals Diffusion tensor imaging on 3-T MRI breast: diagnostic performance in comparison to diffusion-weighted imaging

2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Dalia Abdelhady ◽  
Amany Abdelbary ◽  
Ahmed H. Afifi ◽  
Alaa-eldin Abdelhamid ◽  
Hebatallah H. M. Hassan
Keyword(s):  
Breast Cancer ◽  
Diffusion Tensor Imaging ◽  
Sensitivity And Specificity ◽  
Diffusion Weighted Imaging ◽  
Diffusion Tensor ◽  
Breast Mri ◽  
Breast Lesions ◽  
Dce Mri ◽  
Additional Tool ◽  
Diffusion Weighted

Abstract Background Breast cancer is the most prevalent cancer among females. Dynamic contrast-enhanced MRI (DCE-MRI) breast is highly sensitive (90%) in the detection of breast cancer. Despite its high sensitivity in detecting breast cancer, its specificity (72%) is moderate. Owing to 3-T breast MRI which has the advantage of a higher signal to noise ratio and shorter scanning time rather than the 1.5-T MRI, the adding of new techniques as diffusion tensor imaging (DTI) to breast MRI became more feasible. Diffusion-weighted imaging (DWI) which tracks the diffusion of the tissue water molecule as well as providing data about the integrity of the cell membrane has been used as a valuable additional tool of DCE-MRI to increase its specificity. Based on DWI, more details about the microstructure could be detected using diffusion tensor imaging. The DTI applies diffusion in many directions so apparent diffusion coefficient (ADC) will vary according to the measured direction raising its sensitivity to microstructure elements and cellular density. This study aimed to investigate the diagnostic accuracy of DTI in the assessment of breast lesions in comparison to DWI. Results By analyzing the data of the 50 cases (31 malignant cases and 19 benign cases), the sensitivity and specificity of DWI in differentiation between benign and malignant lesions were about 90% and 63% respectively with PPV 90% and NPV 62%, while the DTI showed lower sensitivity and specificity about 81% and 51.7%, respectively, with PPV 78.9% and NPV 54.8% (P-value ≤ 0.05). Conclusion While the DWI is still the most established diffusion parameter, DTI may be helpful in the further characterization of tumor microstructure and differentiation between benign and malignant breast lesions.

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