Prevalence and Diagnostic Approach to Sleep Apnea in Hemodialysis Patients: A Population Study.

Background. Previous observations found a high prevalence of obstructive sleep apnea (OSA) in the hemodialysis population, but the best diagnostic approach remains undefined. We assessed OSA prevalence and performance of available screening tools to propose a specific diagnostic algorithm. Methods. 104 patients from 6 Swiss hemodialysis centers underwent polygraphy and completed 3 OSA screening scores: STOP-BANG, Berlin's Questionnaire, and Adjusted Neck Circumference. The OSA predictors were identified on a derivation population and used to develop the diagnostic algorithm, which was validated on an independent population. Results. We found 56% OSA prevalence (AHI ≥ 15/h), which was largely underdiagnosed. Screening scores showed poor performance for OSA screening (ROC areas 0.538 [SE 0.093] to 0.655 [SE 0.083]). Age, neck circumference, and time on renal replacement therapy were the best predictors of OSA and were used to develop a screening algorithm, with higher discriminatory performance than classical screening tools (ROC area 0.831 [0.066]). Conclusions. Our study confirms the high OSA prevalence and highlights the low diagnosis rate of this treatable cardiovascular risk factor in the hemodialysis population. Considering the poor performance of OSA screening tools, we propose and validate a specific algorithm to identify hemodialysis patients at risk for OSA for whom further sleep investigations should be considered.

Reversible Reprogramming of Circulating Memory T Follicular Helper Cell Function during Chronic HIV Infection.

Despite the overwhelming benefits of antiretroviral therapy (ART) in curtailing viral load in HIV-infected individuals, ART does not fully restore cellular and humoral immunity. HIV-infected individuals under ART show reduced responses to vaccination and infections and are unable to mount an effective antiviral immune response upon ART cessation. Many factors contribute to these defects, including persistent inflammation, especially in lymphoid tissues, where T follicular helper (Tfh) cells instruct and help B cells launch an effective humoral immune response. In this study we investigated the phenotype and function of circulating memory Tfh cells as a surrogate of Tfh cells in lymph nodes and found significant impairment of this cell population in chronically HIV-infected individuals, leading to reduced B cell responses. We further show that these aberrant memory Tfh cells exhibit an IL-2-responsive gene signature and are more polarized toward a Th1 phenotype. Treatment of functional memory Tfh cells with IL-2 was able to recapitulate the detrimental reprogramming. Importantly, this defect was reversible, as interfering with the IL-2 signaling pathway helped reverse the abnormal differentiation and improved Ab responses. Thus, reversible reprogramming of memory Tfh cells in HIV-infected individuals could be used to enhance Ab responses. Altered microenvironmental conditions in lymphoid tissues leading to altered Tfh cell differentiation could provide one explanation for the poor responsiveness of HIV-infected individuals to new Ags. This explanation has important implications for the development of therapeutic interventions to enhance HIV- and vaccine-mediated Ab responses in patients under ART.

Tukkivannesahojen teräpyörien bombeerauslaitteen kehittäminen

Diplomityössä kehitettiin kannettava työstölaite, jolla voidaan bombeerata tukkivannesahojen suuret teräpyörät omilla laakereillaan paikoillaan sahalinjoissa. Teräpyörät kuluvat käytössä, jolloin ne joudutaan työstämään uudelleen muotoonsa useita kertoja vuodessa. Nykyisin pyörien kehäpinnat hiotaan haluttuun muotoon lähes sadan vuoden ikäiseen keksintöön perustuvalla menetelmällä. Menetelmän suurimpina ongelmina ovat saavutettavan bombeerausmuodon heikko tarkkuus, työstötapahtuman hitaus ja puutteellinen työturvallisuus. Kehitetyn bombeerauslaitteen ja -menetelmän avulla parannetaan kaikkia kolmea merkittävää puutetta. Työssä kartoitettiin kattavasti erilaisia mahdollisia työstömenetelmiä, joita voitaisiin käyttää teräpyörien bombeeraukseen. Parhaaksi vaihtoehdoksi osoittautui sorvaus, jonka avulla teräpyörien kehäpinnat saadaan työstettyä tarkasti, nopeasti ja varmasti käyttämällä tavallisia sorvin työkaluja ja uutta ehdotettua kannettavaa sorvia.

Prevalence and Diagnostic Approach to Sleep Apnea in Hemodialysis Patients: A Population Study.

BACKGROUND: Previous observations found a high prevalence of obstructive sleep apnea (OSA) in the hemodialysis population, but the best diagnostic approach remains undefined. We assessed OSA prevalence and performance of available screening tools to propose a specific diagnostic algorithm. METHODS: 104 patients from 6 Swiss hemodialysis centers underwent polygraphy and completed 3 OSA screening scores: STOP-BANG, Berlin's Questionnaire, and Adjusted Neck Circumference. The OSA predictors were identified on a derivation population and used to develop the diagnostic algorithm, which was validated on an independent population. RESULTS: We found 56% OSA prevalence (AHI ≥ 15/h), which was largely underdiagnosed. Screening scores showed poor performance for OSA screening (ROC areas 0.538 [SE 0.093] to 0.655 [SE 0.083]). Age, neck circumference, and time on renal replacement therapy were the best predictors of OSA and were used to develop a screening algorithm, with higher discriminatory performance than classical screening tools (ROC area 0.831 [0.066]). CONCLUSIONS: Our study confirms the high OSA prevalence and highlights the low diagnosis rate of this treatable cardiovascular risk factor in the hemodialysis population. Considering the poor performance of OSA screening tools, we propose and validate a specific algorithm to identify hemodialysis patients at risk for OSA for whom further sleep investigations should be considered.

Campesinos, Estado y mercado. La conflictividad forestal en el Noroeste de España, León (1870­ ¿1936)

Peer-reviewed

Raideliikenteen opastimien valoyksiköiden koteloiden tuotekehitys

Nykyisin raideliikenteen käytössä olevan opastinjärjestelmän mukaiset opastimet ovat kunnossapidollisesti erittäin haastavia. Niiden korkeus aiheuttaa kunnossapitohenkilöstölle työturvallisuusriskin ja monimutkaiset opastinulokkeet ja - portaalit ovat kalliita rakentaa. Nykyisin käytössä oleva opastinjärjestelmä onkin tarkoitus korvata Opastinjärjestelmä 2010 -nimisellä järjestelmällä, jonka kehitystyö on aloitettu Ratahallintokeskuksessa vuonna 2006. Tämä diplomityö on osa kyseistä kehitystyötä. Työn tarkoituksena on raideliikenteen käyttöön tulevien Opastinjärjestelmä 2010:n mukaisten opastimien valoyksiköiden koteloiden rakenteen suunnittelu ja materiaalinvalinta. Suunnittelutyöhön sisältyvät myös valoyksiköiden häikäisysuojien suunnittelu, sekä opastimien koteloiden liittäminen opastimien jalkoihin. Uusille opastimille suunnitellaan myös putkipaaluperustus. Opastinjärjestelmä 2010:n mukaisten opastimien myötä opastinten sijoittelua voidaan parantaa, ja niiden kunnossapito helpottuu. Uuden järjestelmän opastimien kotelot tarjoavat opastimien valoyksiköille entistä avointa levyrakennetta paremman ilkivaltasuojan. Uusissa opastimissa otetaan käyttöön LED-valoyksiköt, joka vähentää kunnossapitokustannuksia lamppujen vaihtotarpeen pienentyessä.

Experimentos didáticos em química analítica envolvendo separação de fases e pré-concentração

The aim of this work was to propose two different didactic experiments, which can be used in practical classes of analytical chemistry courses. More flexible experiments related to the theme, giving some options to the instructor are proposed. In this way, the Experiment 1 was divided in two parts. In the first one, the visualization of two distinct phases separation is emphasized: the rich and the poor phases in surfactant. In the second part, the metal pre-concentration (Co as example) is emphasized. The Experiment 2 has three different parts. In the first one, the complex formation is pointed out, in the second one, the pH influence is shown and in the last one, the influence of the complexation time is demonstrated.

Efeitos da poluição atmosférica (litorânea e industrial) em isoladores da rede elétrica da região metropolitana de Salvador

The performances of eight kinds of insulators from electrical distribution lines in Salvador-BA, Brazil, were evaluated considering the chemical and physical local environmental pollution. The parameters that were chosen as characteristic for the insulators' properties were leakage current and partial electrical discharge. A data storage processing system and a communication link to the lab were built for data acquisition. The results show that the main contribution to the poor performance of the insulators is settleable magnetite particulate matter on the insulator in addition to the long term wetness time, t4.

Citotoxicidade e genotoxicidade de nanotubos de carbono

There are many controversies regarding the cyto- and genotoxicity of carbon nanotubes (CNTs). In this work, we discuss that many of the incongruous arguments are probably associated with the poor physical-chemical characterization of the CNT samples used in many publications. This manuscript presents examples of carbon nanostructures observed under high resolution electron microscopy that can be found in typical CNT samples, and shows which roles in cyto- and genotoxicity need to be better investigated. Issues concerning chemical treatment are addressed and examples of misunderstandings that can occur during the studies of cyto- and genotoxicity of CNT samples are given.

Avaliação do potencial de uso da hidroxiapatita para fertilização de solos

Plants absorb phosphorus from the soil, which has low levels of this element due to the poor solubility of these compounds in soil and high adsorption capacity of the element by soil particles. Therefore, the purpose of this study was to assess, using hydroxyapatite nanoparticles synthesized in the laboratory, the amount of phosphorus available under different conditions. The results showed that the phosphorus compound had highest solubility in hydroxyapatite sintered at 300°C in an oven for 2h and diluted to 0.05M with MilliQ water, corroborating the theory that the stronger the agglomeration of the nanoparticles, the fewer the pores and the poorer their solubility.

Utilization of retention chemicals in non-wood containing furnishes

The usage of the non-wood pulps in furnishes for various paper grades is the real alternative for substitution of wood fibres in the papermaking. This is especially important now, when the prices for wood are increasing and forest resources are depleting in many regions of our planet. However, there are several problems associated with utilization of such pulps. In terms of the papermaking process one of the main problems is the poor dewatering of the non-wood pulps. This problem can be partially solved by means of retention aids. In the literature part were described technological features of the non-wood pulps as the raw materials for paper production. Moreover, overviews of the retention chemicals and methods for retention measurement were done; special attention was paid to the mechanisms of retention and drainage. Finally, factors affecting on the drainage and retention of non-wood pulps were considered holistically. Particular emphasis was put on the possibility of enzyme treatment for drainage improvement. It was stated that retention aids can significantly improve dewatering of non-wood pulps. In the experimental part the goal was to investigate influence of various microparticle retention aids on the drainage, retention and formation of furnish containing wheat straw pulp, obtained by novel pulping process (Formico™Fib). The parallel test were performed with reference furnish containing only wood pulps. It was found that Bentonite-CPAM retention aid can significantly improve drainage and retention; however formation seems be suffer from such additives. It was stated that performance of the Silica-Starch retention aid significantly depends on the starch dosing sequence and wet-end conditions; this system have shown better formation than other tested retention aids. Silica-CPAM retention aid have provided comparable results in retention and drainage with Bentonite-CPAM, while Silica-starch did not improve dewatering and yielded in lowest filler retention among other aids. Ultimately, optimal dosages for the tested retention chemicals have been suggested.

Laatukustannusten sisäisen raportoinnin kehittäminen Metso Rautpohjan paperi- ja kartonkikonetehtaassa

Tässä diplomityössä on tarkasteltu Metso Rautpohjan laatukustannustiedon sisäisiä raportointitarpeita ja -mahdollisuuksia päätöksenteon tueksi. Tehty tarkastelu liittyy aiemmin Rautpohjassa luotuun laaduttomuuden kustannusten kirjaus- ja seurantajärjestelmään, jonka avulla kyseisiä kustannuksia on organisaatiossa eritelty muista kustannuksista Baan-tietojärjestelmää käyttäen. Tämän työn tavoitteena oli löytää tapaustutkimuksen keinoin laaduttomuuden kustannuksiin liittyviä sisäisiä tietotarpeita, joihin voitaisiin löytää ratkaisuja Data Warehouse (DW) -tietovarastointi- ja raportointitekniikkaa sekä olemassa olevaa laaduttomuuden kustannustietomassaa 2008 hyödyntäen. Tutkimusta varten Rautpohjan organisaatiosta valittiin kullekin toiminnolle niitä edustavat vastuuhenkilöt, joita haastattelemalla pyrittiin selvittämään sisäisiä tietotarpeita laaduttomuuden kustannuksiin liittyen. Työn tuloksena jokaiselle tutkimukseen osallistuneelle toiminnolle luotiin vähintään yksi raporttipohja, jonka avulla niille voidaan jatkossa tuottaa tarvittavaa, kohdennettua laaduttomuuden kustannustietoa omaan toimintaan liittyen. Laaduttomuuden kustannusten rinnalla tässä työssä tutkittiin myös mahdollisia kehitystarpeita Rautpohjan ympäristökustannuksien seurantaan liittyen. Suuremmassa mittakaavassa tällä työllä on pyritty tukemaan laaduttomuuden kustannusten minimointia paitsi Rautpohjassa, mutta myös Metson linjaorganisaatiossa yleisesti. Raportoinnin perimmäisenä tarkoituksena oli mahdollistaa laaduttomuuden kustannusten taustalla olevien syiden ja tapahtumien analysointi, ja sitä kautta edesauttaa laaduttomuuden kustannusten minimoimiseen tähtäävää kehitystyötä. Metso Rautpohjassa toimiviksi havaittuja laaduttomuuden kustannusten seurantaan ja analysointiin käytettyjä menetelmiä voidaan haluttaessa soveltaa myös muissa Metso-yksiköissä.

Effect of pulps fractionation on formation and strength properties of laboratory hand sheets

The objectives of the work were to study the effect of dewatering time varying on formation properties of papersheets, to determine the role of fines fraction in creation of paper with good formation and strength properties of papersheets, and also to study the effect of charge modification of fibers fractionations on formation properties of handsheets. The paper formation is one of the most important structural properties of paper. This property has effect on physical and optical characteristics of paper. In thi work the effect of formation on tensile strength was determined. The formation properties were analyzed by using the AMBERTEC Beta Formation Tester. The PAM addition as a f;locculant agent did some changes in the formation of paper. Paper sheets were also made from different furnishes of both birch and pine pulps. The fibers particles as a fines have great effect on drainability changes. Fines fraction played important role in papermaking. The two kinds of pulps (pine and birch pulps) were also used in this work for investigation of fines role. As it was expected the fines fraction gave positive effect on paper formation, but when fines fraction was added above initial fines content the formation of paper was deteriorated. The effect of paper formation on tensile strength was also determined. In many cases the poor formation of paper had negative effect on strength properties of paper..

Vascular Function in Chronic Kidney Disease and in Renovascular Disease

Cardiovascular mortality is 15 to 30 times higher in patients with chronic kidney disease than in the age-adjusted general population. Even minor renal dysfunction predicts cardiovascular events and death in the general population. In patients with atherosclerotic renovascular disease the annual cardiovascular event and death rate is even higher. The abnormalities in coronary and peripheral artery function in the different stages of chronic kidney disease and in renovascular disease are still poorly understood, nor have the cardiac effects of renal artery revascularization been well characterized, although considered to be beneficial. This study was conducted to characterize myocardial perfusion and peripheral endothelial function in patients with chronic kidney disease and in patients with atherosclerotic renovascular disease. Myocardial perfusion was measured with positron emission tomography (PET) and peripheral endothelial function with brachial artery flow-mediated dilatation. It has been suggested that the poor renal outcomes after the renal artery revascularization could be due to damage in the stenotic kidney parenchyma; especially the reduction in the microvascular density, changes mainly evident at the cortical level which controls almost 80% of the total renal blood flow. This study was also performed to measure the effect of renal artery stenosis revascularization on renal perfusion in patients with renovascular disease. In order to do that a PET-based method for quantification of renal perfusion was developed. The coronary flow reserve of patients with chronic kidney disease was similar to the coronary flow reserve of healthy controls. In renovascular disease the coronary flow reserve was, however, markedly reduced. Flow-mediated dilatation of brachial artery was decreased in patients with chronic kidney disease compared to healthy controls, and even more so in patients with renovascular disease. After renal artery stenosis revascularization, coronary vascular function and renal perfusion did not improve in patients with atherosclerotic renovascular disease, but in patients with bilateral renal artery stenosis, flow-mediated dilatation improved. Chronic kidney disease does not significantly affect coronary vascular function. On the contrary, coronary vascular function was severely deteriorated in patients with atherosclerotic renovascular disease, possibly because of diffuse coronary artery disease and/or diffuse microvascular disease. The peripheral endothelial function was disturbed in patients with chronic kidney disease and even more so in patient with atherosclerotic renovascular disease. Renal artery stenosis dilatation does not seem to offer any benefits over medical treatment in patients with renovascular disease, since revascularization does not improve coronary vascular function or renal perfusion.

Innovaation diffuusio - Case sähköinen palvelualusta kiinteistöalalla

Tämän diplomityön tavoitteena oli selvittää tekijöitä, jotka hidastavat ja estävät kiinteistöalalle kehitetyn sähköisen palvelualustan käyttöönottoa isännöitsijätoimistoissa ja niiden isännöimissä taloyhtiöissä. Osana työtä perehdyttiin innovaation diffuusion liittyvään teoriaan ja kirjallisuuteen. Teoriaosuudessa selvitettiin muun muassa tutkimuksessa apuna käytettäviä malleja ja viitekehyksiä uuden tuotteen markkinointiin liittyvien esteiden jäsentämiseksi. Tutkimus toteutettiin kvalitatiivisena tutkimuksena isännöitsijätoimistojen edustajia haastattelemalla. Merkittävimmät esiin tulleet käyttöönottoa hidastavat tai estävät tekijät liittyivät epävarmuuteen palvelun hyödyistä verrattuna sen käyttöönoton vaatimaan panostukseen, palvelun käyttöönoton edellyttämiin toimintatapojen muutoksiin isännöitsijätoimistossa ja suhteessa taloyhtiöihin, johtamiseen sekä palvelun markkinointiin taloyhtiöille. Johtopäätöksenä oli, että palvelualustan markkinointia on kehitettävä ratkaisukeskeisemmäksi ja palvelun käyttöönoton tukea on parannettava ja tuotteistettava. Lisäksi tukea isännöitsijätoimistoille palvelun markkinointiin ja myyntiin taloyhtiöille on lisättävä.