The new versatile general purpose surface-muon instrument (GPS) based on silicon photomultipliers for μ{\mu}SR measurements on a continuous-wave beam

We report on the design and commissioning of a new spectrometer for muon-spin relaxation/rotation studies installed at the Swiss Muon Source (S$\mu$S) of the Paul Scherrer Institute (PSI, Switzerland). This new instrument is essentially a new design and replaces the old general-purpose surface-muon instrument (GPS) which has been for long the workhorse of the $\mu$SR user facility at PSI. By making use of muon and positron detectors made of plastic scintillators read out by silicon photomultipliers (SiPMs), a time resolution of the complete instrument of about 160 ps (standard deviation) could be achieved. In addition, the absence of light guides, which are needed in traditionally built $\mu$SR instrument to deliver the scintillation light to photomultiplier tubes located outside magnetic fields applied, allowed us to design a compact instrument with a detector set covering an increased solid angle compared to the old GPS.Comment: 11 pages, 11 figure

Vestibular effects of diving

Over the last 45 years, recreational self-contained underwater breathing apparatus (SCUBA) diving as a leisure activity has increased in popularity. According to the Professional Association of Diving Instructors (PADI), more than 23 million diver certificates have been issued across the globe. Given the popularity of scuba diving, it is incumbent on every physician to know and understand the specific medical hazards and conditions associated with scuba diving. Although diving has become more accessible and the equipment is much safer now, diving still has its inherent dangers. Each year incidents occur, ranging from seasickness and sinus problems to heart conditions and mortality. More than 80% of all diving complications occur in the head and neck region. A number of studies have found that diving can lead to the development of vestibular disorders such as: Barotrauma, Decompression sickness, Otitis externa, Bilateral exostoses, Chronic sinusitis (barosinusitis), Serous tubotympanic catarrh, Tinnitus, Dizziness, Vertigo.The aim of this paper was to share our experience in the field of treating patients with different types of ENT disorders after or before a diving session. We briefly summarized the most important information for some of the disorders.We included in our study for a period of 12 years: a total of 24 patients (four females and 20 males), who dive. They were between 25 and 55 years of age. Some presented in clinics with an ENT disorder. 19 were professional, qualified divers, five (three males and two females) dove for the first time. On all 24 patients we performed: audiometry tests, Tympanometry tests, OAE, Static and dynamic vestibular tests, vHIT – in the last five years, otoscopy examination, dental check-ups.All divers – no matter professionalists or not – should follow these recommendations: a thorough prophylactic ENT check-up should be performed before an active diving session. Chronic ENT inflammations should be addressed in a timely manner. Divers should follow all instructions from the certified Diving Associations

Prediction of sanding in subsurface hydrocarbon reservoirs.

Sand production in oil and gas wells can occur if the fluid velocity exceeds a certain value. Due to drilling operations, the mechanical stresses can exceed the load bearing capacity of the rock. As the local stresses exceed certain level, a certain amount of rock is fractured into sand. Then, the sand is carried by the fluid through the wellbore depending on the flow rate. The amount of the solids can be less than a few grams per cubic meter of reservoir fluid or an essential amount. In the later case erosion of the rock and removing sufficient quantities of rock can occur. This can produce subsurface cavities which collapse and destroy the well. When sanding is unavoidable it is necessary to estimate the characteristics of the process. Our aim was to generate a simple one-dimensional local model, which predicts the volume of sanding, the radius and the porosity of the yielded zone. Such model will help the company in the development of complex 3D models

Changes in the function of the anal sphincter complex and generated anal pressure at different anatomical levels after elastic ligature application in patients with anal fistula

Purpose: The purpose of the present study was to measure by means of especially developed apparatus the anal and intrarectal pressure before and after different operations for perianal fistulas as well as to correlate the degree of incontinence evaluated by Fecal Incontinence Severity Index (FISI) with changes in the measured pressures and type of operation used.Material and methods: The study covered 311 patients with perianal fistulas who were operated with several methods. Anal canal pressures at 5 different levels were measured by the especially developed apparatus at rest, squeezing and cough, before and after 6 months of operation. FISI form was used for incontinence detection.Results: Resting, squeezing and cough pressures were higher in men before and after operations. Average reduction of anal rest pressure by 10-15%, at contraction by 20-25% and at cough by 5-10% resulted in mild incontinence according to FISI score. Average reduction of anal rest pressure by 20-25%, at contraction by 30-40% and at cough by 20-25% correlated with postoperative moderate degree of incontinence according to FISI score. No severe incontinence was registered by FISI examination. Usage of the method of elastic ligation of perianal fistulas, i.e. the method of Hippocrates-Thoma Junescu caused the highest percentage of postoperative mild degree incontinence (15,9%) and moderate one (4,3%) by FISI. No patients presented with severe degree of incontinence.Conclusion: The method of anal sphincter tonometry demonstrated a significant reduction of anal pressure after surgery for anal fistulas. This objective decrease of anal sphincter tone correlated with the higher FISI score arguing of postoperative incontinence. The method of Hippocrates-Thoma-Junescu resulted in the highest rate of incontinence (around 20%) and anal pressure reduction

Artificial intelligence – the new suggestion for biomedicine, dentistry and healthcare

The development of technologies based on Artificial Intelligence (AI) and their application in medicine is growing rapidly. Innovations in digital technology, telemedicine, 5G technology and artificial intelligence (AI) create new opportunities for the development of the healthcare system. The aim of the present study is to explore the possibilities for the application of artificial intelligence in biomedicine, dentistry, healthcare and healthcare. In recent years there have been many major innovations, including the introduction of many new information and communication technologies. Digital innovations, including the further inclusion of telemedicine, the development of 5th generation wireless networks (5G) and artificial intelligence (AI) approaches, create an exceptional ecosystem for new health opportunities. The digital health sector creates a favorable environment for the provision of health services at a very high level

muCool: A novel low-energy muon beam for future precision experiments

Experiments with muons ($\mu^{+}$) and muonium atoms ($\mu^{+}e^{-}$) offer several promising possibilities for testing fundamental symmetries. Examples of such experiments include search for muon electric dipole moment, measurement of muon $g-2$ and experiments with muonium from laser spectroscopy to gravity experiments. These experiments require high quality muon beams with small transverse size and high intensity at low energy. At the Paul Scherrer Institute, Switzerland, we are developing a novel device that reduces the phase space of a standard $\mu^{+}$ beam by a factor of $10^{10}$ with $10^{-3}$ efficiency. The phase space compression is achieved by stopping a standard $\mu^{+}$ beam in a cryogenic helium gas. The stopped $\mu^{+}$ are manipulated into a small spot with complex electric and magnetic fields in combination with gas density gradients. From here, the muons are extracted into the vacuum and into a field-free region. Various aspects of this compression scheme have been demonstrated. In this article the current status will be reported.Comment: 8 pages, 5 figures, TCP 2018 conference proceeding

Microchannel avalanche photodiode with wide linearity range

Design and physical operation principles of new microchannel avalanche photodiode (MC APD) with gain up to 10^5 and linearity range improved an order of magnitude compared to known similar devices. A distinctive feature of the new device is a directly biased p-n junction under each pixel which plays role of an individual quenching resistor. This allows increasing pixel density up to 40000 per mm^2 and making entire device area sensitive.Comment: Submitted to Journal of Technical Physic

Deroofing - a method of choice in the treatment of suppurative perineal hidradenitis

Purpose: Suppurative hidradenitis is a chronic relapsing inflammatory disease that affects the apocrine sweat glands. Therefore, it is most often located in the axilla, groin and perianal area. Usually, people of working age affected. Perineal and perianal locations cover about 37% of the total morbidity rate and are more common in males. The objective of this study was to share our experience with the application of deroofing for the treatment of purulent perineal hidradenitis.Material and methods: This prospective interventional study covered 13 patients with suppurative fistulasing hidradenitis of perineum treated in Division of Coloproctology and Septic Surgery, Georgi Stranski University Hospital of Pleven for the period from 2008 till 2013.Results: The interval between the occurrence of disease and its surgical treatment was very long - from two to 36 years (average of 9,2 years). It resulted from the progression of the disease with enlarged soft tissue involvement. Sometimes, the disease was complicated by chroniosepsis. The average hospital stay was 13,5-day long. Operative wounds healed secondarily at an average of about 30 days. The patients were followedup for six months, one year and two years. Two patients with relapses on the sixth postoperative month were hospitalized again. The surgical intervention warranted good results.Conclusion: Treatment of suppurative hidradenitis of the perineum is complex, both in terms of local status and systematic violations resulting in chronic infection. There are numerous surgical techniques for treating this pathology. The advantages of deroofing are the following: minimal trauma to the patient, application by using local anesthesia at the early stage in order to minimize hospital stay, no need of special equipment, a lower recurrence rate than the other methods and formation of aesthetically acceptable scar

The Kabachnik–Fields Reaction in the Synthesis of Polyaminophosphonate Derivatives of p-tert-Butylthiacalix[4]arene

© 2018, Pleiades Publishing, Ltd. Novel derivatives of p-tert-butylthiacalix[4]arene containing four or eight 1-aminophosphonate groups at the lower rim of the macrocycle in 1,3-alternate conformation have been synthesized via the Kabachnik–Fields reaction. These compounds are promising synthetic receptors for biologically important acids. It has been shown that complete phosphorylation of the first generation dendrimer containing eight primary amino groups is impeded in the case of cyclic ketones