Helical Undulator Based on Partial Redistribution of Uniform Magnetic Field

A new type of helical undulator based on redistribution of magnetic field of a solenoid by ferromagnetic helix has been proposed and studied both in theory and experiment. Such undulators are very simple and efficient for promising sources of coherent spontaneous THz undulator radiation from dense electron bunches formed in laser-driven photo-injectors

Hormonal priming alleviates salt stress in hot Pepper (Capsicum annuum L.)

Germination and seedling establishment are critical stages in the life cycle of plants especially under stress conditions. Different methodologies have been adopted by plant physiologists in different crops to alleviate salt stress. Seed priming has proven beneficial in this regard in many important agricultural crops. The effect of seed priming with salicylic acid (SA) and acetylsalicylic acid (ASA) in improving seed vigour and salt tolerance of hot pepper seedlings was evaluated. Concentrations over 1.0 mM of ASA or SA showed adverse effects on seed emergence. Seeds primed with SA (0.8 mM) and ASA (0.2 mM) were sown in medium at different salinity levels [0, 3, 6 and 9 dS m-1]. Both, SA and ASA treatments showed significantly better results over the control by improvement in time taken to 50% emergence, final emergence percentage, root and shoot length, seedling fresh and dry weight and seedling vigour. Overall, acetylsalicylic acid exhibited superiority over salicylic acid. Our results indicate that hormonal priming, especially with acetylsalicylic acid, can be a good treatment for hot pepper to enhance uniformity of emergence and seedling establishment under normal as well as saline conditions

Development and international validation of custom-engineered and code-free deep-learning models for detection of plus disease in retinopathy of prematurity: a retrospective study.

BACKGROUND: Retinopathy of prematurity (ROP), a leading cause of childhood blindness, is diagnosed through interval screening by paediatric ophthalmologists. However, improved survival of premature neonates coupled with a scarcity of available experts has raised concerns about the sustainability of this approach. We aimed to develop bespoke and code-free deep learning-based classifiers for plus disease, a hallmark of ROP, in an ethnically diverse population in London, UK, and externally validate them in ethnically, geographically, and socioeconomically diverse populations in four countries and three continents. Code-free deep learning is not reliant on the availability of expertly trained data scientists, thus being of particular potential benefit for low resource health-care settings. METHODS: This retrospective cohort study used retinal images from 1370 neonates admitted to a neonatal unit at Homerton University Hospital NHS Foundation Trust, London, UK, between 2008 and 2018. Images were acquired using a Retcam Version 2 device (Natus Medical, Pleasanton, CA, USA) on all babies who were either born at less than 32 weeks gestational age or had a birthweight of less than 1501 g. Each images was graded by two junior ophthalmologists with disagreements adjudicated by a senior paediatric ophthalmologist. Bespoke and code-free deep learning models (CFDL) were developed for the discrimination of healthy, pre-plus disease, and plus disease. Performance was assessed internally on 200 images with the majority vote of three senior paediatric ophthalmologists as the reference standard. External validation was on 338 retinal images from four separate datasets from the USA, Brazil, and Egypt with images derived from Retcam and the 3nethra neo device (Forus Health, Bengaluru, India). FINDINGS: Of the 7414 retinal images in the original dataset, 6141 images were used in the final development dataset. For the discrimination of healthy versus pre-plus or plus disease, the bespoke model had an area under the curve (AUC) of 0·986 (95% CI 0·973-0·996) and the CFDL model had an AUC of 0·989 (0·979-0·997) on the internal test set. Both models generalised well to external validation test sets acquired using the Retcam for discriminating healthy from pre-plus or plus disease (bespoke range was 0·975-1·000 and CFDL range was 0·969-0·995). The CFDL model was inferior to the bespoke model on discriminating pre-plus disease from healthy or plus disease in the USA dataset (CFDL 0·808 [95% CI 0·671-0·909, bespoke 0·942 [0·892-0·982]], p=0·0070). Performance also reduced when tested on the 3nethra neo imaging device (CFDL 0·865 [0·742-0·965] and bespoke 0·891 [0·783-0·977]). INTERPRETATION: Both bespoke and CFDL models conferred similar performance to senior paediatric ophthalmologists for discriminating healthy retinal images from ones with features of pre-plus or plus disease; however, CFDL models might generalise less well when considering minority classes. Care should be taken when testing on data acquired using alternative imaging devices from that used for the development dataset. Our study justifies further validation of plus disease classifiers in ROP screening and supports a potential role for code-free approaches to help prevent blindness in vulnerable neonates. FUNDING: National Institute for Health Research Biomedical Research Centre based at Moorfields Eye Hospital NHS Foundation Trust and the University College London Institute of Ophthalmology. TRANSLATIONS: For the Portuguese and Arabic translations of the abstract see Supplementary Materials section

Design of a Permanent Magnet Wiggler for a THz Free Electron Laser

A THz free electron laser is being built in Ariel University. Upon completion it is intended to become a user facility. The free electron laser is designed to emit radiation between 1 and 5 THz. It is planned to operate in the super radiance regime. The anticipated output of the free electron laser is in excess of 150 kW instantaneous power. An essential part of every free electron laser is a device generating a periodic magnetic field denoting the wiggler. Here we describe a design of a classical Halbach type permanent magnetic wiggler for the THz free electron laser. The main novelty in this paper is the choice of wiggler parameters suitable for operation in the THz frequency range. Considerations such as radiation wave length, wiggler gain and electron optics are taken into account

Severe acute renal failure due to tubulointerstitial nephritis, pancreatitis, and hyperthyroidism in a patient during rifampicin therapy

It is well known that rifampicin can cause nephrotoxicity. Rifampicin-related pancreatitis and hyperthyroidism are rarely reported in the same patient in the presence of tubulointerstitial nephritis. Reported herein is the medical management of a patient with hemolytic anemia, acute renal failure, pancreatitis, and hyperthyroidism during with rifampicin therapy. A 50-year-old man was admitted to the hospital owing to abdominal colic and acute renal failure. He was treated with 2 courses of tetracycline-rifampicin for brucellosis 3 weeks and 4 months prior to admission. Physical examination showed blood pressure of 130/70 mm Hg, pulmonary crackles, and edema. Laboratory findings are detailed in the case report. Findings of abdominal ultrasonography suggested edematose pancreatitis and thyroid ultrasonography showed several solid nodules. Renal biopsy showed tubulointerstitial nephritis. Although rifampicin-related tubulointerstitial nephritis and acute renal failure are not uncommon during rifampicin therapy, the convergence of hyperthyroidism, pancreatitis, tubulointerstitial nephritis, and acute renal failure rarely presents in the same patient. Although pancreatitis, tubulointerstitial nephritis, and acute renal failure were ameliorated with corticoid therapy within 2 months, hyperthyroidism continued and required antithyroid therapy. In conclusion, rifampicin may trigger hyperthyroidism in patients with goiter. © 2005 Health Communications Inc

Different glomerular pathologies in sickle cell anemia

WOS: 000224863300014PubMed ID: 15571189

A unique form of polycythemia associated with minimal change disease

PubMedID: 15467313Objective: To present a case with nephrotic syndrome due to minimal change disease and polycythemia. Clinical Presentation and Intervention: A 20-year-old female was admitted to our clinic for edema and severe proteinuria present with minimal change disease since the age of 7 years. Polycythemia was found during the last activation of nephrotic syndrome. The patient was placed on glucocorticoid therapy that caused disappearance of edema, proteinuria and polycythemia. Ten months later both hemoglobin and hematocrit levels were within normal range. Conclusion: This patient with nephrotic syndrome due to minimal change disease and polycythemia was successfully treated with glucocorticoid. Copyright © 2004 S. Karger AG, Basel