Twenty-four-hour esophageal pH monitoring in children and adolescents with chronic and/or recurrent rhinosinusitis

Gastroesophageal reflux (GER) disorder was studied in children and adolescents with chronic and/or recurrent rhinosinusitis not associated with bronchial asthma. Ten children with a clinical and radiological diagnosis of chronic and/or recurrent rhinosinusitis, consecutively attended at the Pediatric Otolaryngology Outpatient Clinic, Federal University of São Paulo, were evaluated. Prolonged esophageal pH monitoring was used to investigate GER disorder. The mean age of the ten patients evaluated (eight males) was 7.4 ± 2.4 years. Two patients presented vomiting as a clinical manifestation and one patient presented retrosternal pain with a burning sensation. Twenty-four-hour esophageal pH monitoring was performed using the Sandhill apparatus. An antimony probe electrode was placed in the lower third of the esophagus, confirmed by fluoroscopy and later by a chest X-ray. The parameters analyzed by esophageal pH monitoring included: total percent time of the presence of acid esophageal pH, i.e., pH below 4 (<4.2%); total number of acid episodes (<50 episodes); number of reflux episodes longer than 5 min (3 or less), and duration of the longest reflux episode (<9.2 min). One patient (1/10, 10%) presented a 24-h esophageal pH profile compatible with GER disorder. This data suggest that an association between chronic rhinosinusitis not associated with bronchial asthma and GER disorder may exist in children and adolescents, especially in those with compatible GER disorder symptoms. In these cases, 24-h esophageal pH monitoring should be performed before indicating surgery, since the present data suggest that 10% of chronic rhinosinusitis surgeries can be eliminated.

Monitoring renal function: measured and estimated glomerular filtration rates - a review

Chronic kidney disease (CKD) is a world-wide public health problem, with adverse outcomes of kidney failure, cardiovascular disease, and premature death. This finding has led to the hypothesis that earlier recognition of kidney disease and successful intervention may improve outcome. The National Kidney Foundation, through its Kidney Disease Outcomes Quality Initiative (K/DOQI), and other National institutions recommend glomerular filtration rate (GFR) for the definition, classification, screening, and monitoring of CKD. Blood creatinine clearance, the most widely used clinical marker of kidney function, is now recognized as an unreliable measure of GFR because serum creatinine is affected by age, weight, muscle mass, race, various medications, and extra-glomerular elimination. Cystatin C concentration is a new and promising marker for kidney dysfunction in both native and transplanted kidneys. Because of its low molecular weight, cystatin C is freely filtered at the glomerulus and is almost completely reabsorbed and catabolized, but not secreted, by tubular cells. Given these characteristics, cystatin C concentration may be superior to creatinine concentration in detecting chronic kidney disease. This review aims to evaluate from recent literature the clinical efficiency and relevance of these GFR markers in terms of screening CKD.

Sensor communication in Smart cities and regions: An efficient IoT-based remote health monitoring system

Recent advances in Information and Communication Technology (ICT), especially those related to the Internet of Things (IoT), are facilitating smart regions. Among many services that a smart region can offer, remote health monitoring is a typical application of IoT paradigm. It offers the ability to continuously monitor and collect health-related data from a person, and transmit the data to a remote entity (for example, a healthcare service provider) for further processing and knowledge extraction. An IoT-based remote health monitoring system can be beneficial in rural areas belonging to the smart region where people have limited access to regular healthcare services. The same system can be beneficial in urban areas where hospitals can be overcrowded and where it may take substantial time to avail healthcare. However, this system may generate a large amount of data. In order to realize an efficient IoT-based remote health monitoring system, it is imperative to study the network communication needs of such a system; in particular the bandwidth requirements and the volume of generated data. The thesis studies a commercial product for remote health monitoring in Skellefteå, Sweden. Based on the results obtained via the commercial product, the thesis identified the key network-related requirements of a typical remote health monitoring system in terms of real-time event update, bandwidth requirements and data generation. Furthermore, the thesis has proposed an architecture called IReHMo - an IoT-based remote health monitoring architecture. This architecture allows users to incorporate several types of IoT devices to extend the sensing capabilities of the system. Using IReHMo, several IoT communication protocols such as HTTP, MQTT and CoAP has been evaluated and compared against each other. Results showed that CoAP is the most efficient protocol to transmit small size healthcare data to the remote servers. The combination of IReHMo and CoAP significantly reduced the required bandwidth as well as the volume of generated data (up to 56 percent) compared to the commercial product. Finally, the thesis conducted a scalability analysis, to determine the feasibility of deploying the combination of IReHMo and CoAP in large numbers in regions in north Sweden.

Value perceptions of measurement and monitoring system customers

The value that the customer perceives from a supplier’s offering, impacts customer’s decision making and willingness to pay at the time of the purchase, and the overall satisfaction. Thus, for a business supplier, it is critical to understand their customers’ value perceptions. The objective of this thesis is to understand what measurement and monitoring system customers value, by examining their key purchasing criteria and perceived benefits. Theoretical part of this study consists on reviewing relevant literature on organizational buying behavior and customer perceived value. This study employs a qualitative interview research method. The empirical part of this research consisted of conducting 20 in-depth interviews with life science customers in USA and in Europe. Quality and technical features are the most important purchasing criteria, while product-related benefits seem to be the most important perceived benefits. At the marketing of the system, the emphasis should be at which regulations the system complies with, references of supplier’s prior experience, the reliability and usability of the system, and total costs. The benefits that should be emphasized are the better control of customer’s process, and the proof of customer’s product quality

Optimizing counterparty credit risk portfolio by reducing exposure at default variance

Rahoitusyhtiöt pitävät omaa pääomaa taseessa harvinaisen suuria markkinamuutoksia varten ja tämän pääoman määrä on ohjattu valvontaviranomaisten toimesta. Euroopassa Basel akordi antaa suuntaviivat näille säädöksille. 2007 vuoden finanssikriisin jälkeen rahoitusyhtiöt sekä valvojat ovat olleet entistä kiinnostuneempia pääoman riittävyydestä. Tutkimuksia riskistä, säädöksistä ja pääomavaateen madaltamisesta on tehty aikaisemmin, mutta tässä tutkimuksessa keskitytään vaateen jatkuvan muutoksen suuruuteen. Tutkimus sisältää hypoteettisen vastapuoliriski portfolion, jossa on mukana valuuttajohdannaisia. Tätä portfoliota simuloidaan eri tavoin, jotta nähtäisiin kuinka suuri vaikutus portfolion koostumuksella voi olla pääomavaateen varianssiin. Jos tämä muuttuja on merkittävä, pitäisikö rahoitusyhtiöiden yrittää pienentää muutosta, jotta yhtiöiden varapääoman määrää voitaisiin alentaa? Tutkimuksessa on myös haastateltu Suomen johtavia vastapuoliriski asiantuntijoita, jotta nähtäisiin rahoitusalan oma näkemys asian merkittävyydestä. Tutkimusmenetelminä toimivat haastattelut sekä numeerinen analyysi hypoteettisella portfoliolla. Kaupat tähän vastapuoliriski portfolioon on luotu 14 vuoden ajalle ja se sisältää ainoastaan valuuttajohdannaisia viidessä eri valuutassa. Riski lasketaan markkina-arvo menetelmällä, joista lasketaan VaR-mallilla tulevaisuuden riski nettoutuksen kera. Portfolion rakennetta muutetaan simuloinneissa, jotta nähtäisiin vaikutus tulevaisuuden riskeille, joita käytetään edustamaan pääomavaateen määrää ja sen vaihtelua yli ajan. Portfolioiden riskejä lasketaan myös rasituskokeiden avulla, jotta tuloksista saataisiin mahdollisimman todenmukaisia. Analyyttinen osuus tutkimuksesta näyttää sen, että tämän kaltainen optimointi on suuresti riippuvainen alkuperäisestä portfoliosta, jonka määrittää yleisesti rahoitusyhtiön myyntistrategia. Yleisesti ottaen pääomavaateen varianssin muutos voi simuloinneissa olla melko suurta, varsinkin jos mukaan huomioidaan rasitus testit, puuttuvat tuotteet sekä muut pääomavaateen laskentaan huomioitavat seikat. Haastatteluissa saatiin selville millainen optimointi voisi olla mahdollista todellisuudessa. Huomattiin myös että tämän kaltainen ajattelumalli on jo huomattu alalla ennestään. Jon Gregory jopa mainitsi, että jotkin rahoitusyhtiöt ovat enemmän kiinnostuneita muutosten pienentämisestä kuin itse pääomavaateen suuruudesta. Näyttääkin siltä, että tämän aihepiiri vaatisi entistä enemmän tutkimusta, sillä sitä ei ennestään vielä ole, ja rahoitusyhtiöt ovat jo alkaneet etsimään uusia keinoja selvitäkseen rahoitusalalla, joka on yhä entisestään kilpailullisempi.

Monitoring of wine aging process by electrospray ionization mass spectrometry

The characterization of wine samples by direct insertion electrospray ionization mass spectrometry (ESI-MS), without pre-treatment or chromatographic separation, in a process denominated fingerprinting, has been applied to several samples of wine produced with grapes of the Pinot noir, Merlot and Cabernet Sauvignon varieties from the state o Rio Grande do Sul, in Brazil. The ESI-MS fingerprints of the samples detected changes which occurred during the aging process in the three grape varieties. Principal Component Analysis (PCA) of the negative ion mode fingerprints was used to group the samples, pinpoint the main changes in their composition, and indicate marker ions for each group of samples.

BK polyomavirus in Kidney transplant recipients: screening, monitoring and clinical management

BK polyomavirus (BKPyV) is a causal agent of nephropathy, ureteral stenosis and hemorrhagic cystitis in kidney transplant recipients, and is considered an important emerging disease in transplantation. Regular screening for BKPyV reactivation mainly during the first 2 years posttransplant, with subsequent pre-emptive reduction of immunosuppression is considered the best option to avoid disease progression, since successful clearance or reduction of viremia is achieved in the vast majority of patients within 6 months. The use of drugs with antiviral properties for patients with persistent viremia has been attempted despite unclear benefits. Clinical manifestations of BKPyV nephropathy, current strategies for diagnosis and monitoring of BKPyV infection, management of immunosuppressive regimen after detection of BKPyV reactivation and the use of antiviral drugs are discussed in this review.

Variance reduction properties of dynamic hedging models - empirical evidence from BRICS countries

This Master’s Thesis analyses the effectiveness of different hedging models on BRICS (Brazil, Russia, India, China, and South Africa) countries. Hedging performance is examined by comparing two different dynamic hedging models to conventional OLS regression based model. The dynamic hedging models being employed are Constant Conditional Correlation (CCC) GARCH(1,1) and Dynamic Conditional Correlation (DCC) GARCH(1,1) with Student’s t-distribution. In order to capture the period of both Great Moderation and the latest financial crisis, the sample period extends from 2003 to 2014. To determine whether dynamic models outperform the conventional one, the reduction of portfolio variance for in-sample data with contemporaneous hedge ratios is first determined and then the holding period of the portfolios is extended to one and two days. In addition, the accuracy of hedge ratio forecasts is examined on the basis of out-of-sample variance reduction. The results are mixed and suggest that dynamic hedging models may not provide enough benefits to justify harder estimation and daily portfolio adjustment. In this sense, the results are consistent with the existing literature.

Monitoring Directed Energy Deposition Processes in Additive Manufacturing

The purpose of this study is to find out how laser based Directed Energy Deposition processes can benefit from different types of monitoring. DED is a type of additive manufacturing process, where parts are manufactured in layers by using metallic powder or metallic wire. DED processes can be used to manufacture parts that are not possible to manufacture with conventional manufacturing processes, when adding new geometries to existing parts or when wanting to minimize the scrap material that would result from machining the part. The aim of this study is to find out why laser based DED-processes are monitored, how they are monitored and what devices are used for monitoring. This study has been done in the form of a literature review. During the manufacturing process, the DED-process is highly sensitive to different disturbances such as fluctuations in laser absorption, powder feed rate, temperature, humidity or the reflectivity of the melt pool. These fluctuations can cause fluctuations in the size of the melt pool or its temperature. The variations in the size of the melt pool have an effect on the thickness of individual layers, which have a direct impact on the final surface quality and dimensional accuracy of the parts. By collecting data from these fluctuations and adjusting the laser power in real-time, the size of the melt pool and its temperature can be kept within a specified range that leads to significant improvements in the manufacturing quality. The main areas of monitoring can be divided into the monitoring of the powder feed rate, the temperature of the melt pool, the height of the melt pool and the geometry of the melt pool. Monitoring the powder feed rate is important when depositing different material compositions. Monitoring the temperature of the melt pool can give information about the microstructure and mechanical properties of the part. Monitoring the height and the geometry of the melt pool is an important factor in achieving the desired dimensional accuracy of the part. By combining multiple different monitoring devices, the amount of fluctuations that can be controlled will be increased. In addition, by combining additive manufacturing with machining, the benefits of both processes could be utilized.

Real-time adaptive control of ultra-fast laser scribing process with spectrometer online monitoring

There exist several researches and applications about laser welding monitoring and parameter control but not a single one have been created for controlling of laser scribing processes. Laser scribing is considered to be very fast and accurate process and thus it would be necessary to develop accurate turning and monitoring system for such a process. This research focuses on finding out whether it would be possible to develop real-time adaptive control for ultra-fast laser scribing processes utilizing spectrometer online monitoring. The thesis accurately presents how control code for laser parameter tuning is developed using National Instrument's LabVIEW and how spectrometer is being utilized in online monitoring. Results are based on behavior of the control code and accuracy of the spectrometer monitoring when scribing different steel materials. Finally control code success is being evaluated and possible development ideas for future are presented.

Real-time monitoring of laser scribing process utilizing high-speed camera

Currently, laser scribing is growing material processing method in the industry. Benefits of laser scribing technology are studied for example for improving an efficiency of solar cells. Due high-quality requirement of the fast scribing process, it is important to monitor the process in real time for detecting possible defects during the process. However, there is a lack of studies of laser scribing real time monitoring. Commonly used monitoring methods developed for other laser processes such a laser welding, are sufficient slow and existed applications cannot be implemented in fast laser scribing monitoring. The aim of this thesis is to find a method for laser scribing monitoring with a high-speed camera and evaluate reliability and performance of the developed monitoring system with experiments. The laser used in experiments is an IPG ytterbium pulsed fiber laser with 20 W maximum average power and Scan head optics used in the laser is Scanlab’s Hurryscan 14 II with an f100 tele-centric lens. The camera was connected to laser scanner using camera adapter to follow the laser process. A powerful fully programmable industrial computer was chosen for executing image processing and analysis. Algorithms for defect analysis, which are based on particle analysis, were developed using LabVIEW system design software. The performance of the algorithms was analyzed by analyzing a non-moving image from the scribing line with resolution 960x20 pixel. As a result, the maximum analysis speed was 560 frames per second. Reliability of the algorithm was evaluated by imaging scribing path with a variable number of defects 2000 mm/s when the laser was turned off and image analysis speed was 430 frames per second. The experiment was successful and as a result, the algorithms detected all defects from the scribing path. The final monitoring experiment was performed during a laser process. However, it was challenging to get active laser illumination work with the laser scanner due physical dimensions of the laser lens and the scanner. For reliable error detection, the illumination system is needed to be replaced.