Separation of ammonia and carbon dioxide by adsorption

Tässä työssä on tutkittu ammoniakin ja hiilidioksidin erottamista adsorptio prosessilla ja suunniteltiin paineen muunteluun perustuvan adsorptioprosessin (PSA) käyttöä. Työn tarkoituksena oli laskea adsorptioon perustuvan prosessin kannattavuus melamiinitehtaan poistokaasujen erotuksessa. Tätä varten työssä suunniteltiin tehdasmitta-kaavainen prosessi ja arvioitiin sen kannattavuus. Työssä mitattiin adsorptiotasapainot, joiden perusteella sovitettiin sopiva kokeellinen adsorptioisotermi. Adsorptioisotermi lisättiin simulointiohjelmaan, jonka avulla suunniteltiin kaksi vaihtoehtoista pilot laitteistoa kaasujen erottamiseksi. Toisella pilot laitteistolla saadaan mitattua vain läpäisykäyrät, mutta paremmalla versiolla saadaan myös tietoa erotettujen komponenttien puhtaudesta. Suunnittelun tärkeimpiä lähtökohtia on molempien komponenttien mahdollisimman korkea puhtaus ja talteenottoaste. Täysimittakaavainen tehdas suunniteltiin simulointiohjelmiston avulla kahdelle eri kapasiteetille ja arvioitiin niiden kustannukset ja kannattavuus. Adsorptioprosessit osoittautuivat kannattaviksi kaasuseoksen erottamisessa kummassakin tapauksessa

Effects of inorganic nitrogen (NH4Cl) and biodegradable organic carbon (CH3COONa) additions on a pilot-scale seawater biofilter

Biofilters degrade only a small fraction of the natural organic matter (NOM) contained in seawater which is the leading cause of biofouling in downstream processes. This work studies the effects of chemical additions on NOM biodegradation by biofilters. In this work, biofiltration of seawater with an empty bed contact time (EBCT) of 6 min and a hydraulic loading rate of 10 m h-1 reduces the biological oxygen demand (BOD7) by 8%, the dissolved organic carbon (DOC) by 6% and the UV absorbance at 254 nm (A254) by 7%. Different amounts of ammonium chloride are added to the seawater (up to twice the total dissolved nitrogen in untreated seawater) to study its possible effect on the removal of NOM by a pilot-scale biofilter. Seawater is amended with different amounts of easily biodegradable dissolved organic carbon (BDOC) supplied as sodium acetate (up to twice the DOC) for the same purpose. The results of this work reveal that the ammonium chloride additions do not significantly affect NOM removal and the sodium acetate is completely consumed by the biofiltration process. For both types of chemical additions, the BOD7, DOC and A254 in the outlet stream of the biofilter are similar to the values for the untreated control. These results indicate that this biofilter easily removes the BDOC from the seawater when the EBCT is not above 6 min. Furthermore, nitrogen does not limit the NOM biodegradation in seawater under these experimental conditions.

External assessment of the Early Mortality Risk Score in patients with adenocarcinoma undergoing pancreaticoduodenectomy.

BACKGROUND: Pancreaticoduodenectomies (PD) still have a substantial mortality rate. Recently, different scores have been published to predict the mortality risk pre-operatively after PD. This retrospective study was designed to perform an external assessment of an Early Mortality Risk Score (EMRS). METHODS: From 2000 to 2012, all PD cases performed at our institution were documented. Only patients treated for pancreatic head adenocarcinomas were included. Survival time and EMRS (based on age, tumour size, tumour differentiation and comorbidities) were calculated for every patient. Relative risks (RR) of early death 9 and 12 months after PD were then calculated. RESULTS: Of 270 PD for various aetiologies, 120 PD for adenocarcinomas were included. The median follow-up was 37 months, and the overall median survival was 19 months. EMRS of 4 showed a mortality RR of 5.1 at 9 months (P = 0.048) and of 4.5 at 12 months (P = 0.020). CONCLUSIONS: EMRS of 4 is a predictor of tumour-related mortality at 9 and 12 months after PD for adenocarcinoma. The EMRS was externally assessed in our patient cohort and can be implemented in clinical practice. Clinical implications of this score still need to be studied.

External Location Factors of Finnish Direct Investment in Central and Eastern European Transitional Economies

Tutkimuksen päätavoitteena oli selvittää suomalaisten suorien investointien maan valintaan vaikuttavia tekijöitä Itä- ja Keski-Euroopan kymmenessä siirtymätaloudessa. Empiirisessä osuudessa tarkasteltiin suomalaisten yritysten tärkeimpiä sijaintitekijöitä alueella ja yrityskohtaisten tekijöiden vaikutusta sijaintitekijöihin. Tutkimuksessa selvitettiin myös yritysten päämotiiveja investoida maihin. Laaditun investointikriteeristön mukaan maat pystyttiin laittamaan paremmuusjärjestykseen suomalaisen investoijan kannalta. Empiirisen osuuden aineisto kerättiin postikyselylomakkeella yrityksiltä, joilla on tai jotka ovat suunnittelemassa investointeja näihin maihin. Tutkimusote oli kvantitatiivinen. Tutkimustulokset osoittavat, että suomalaiset investoijat valitsevat Itä- ja Keski-Euroopan maan investointikohteeksi pääasiassa markkinapotentiaalin ja edullisten kustannusten perusteella. Myös infrastruktuuri vaikuttaa maan valintaan. Eri aloilla toimivien yritysten sijaintitekijöiden painotuksissa havaittiin eroja. Yrityksen koko ja päämotiivi vaikuttivat sijaintitekijöiden painotuksiin. Investointikriteereiden mukaan kaksi parasta investointimaata suomalaisille investoijille ovat Puola ja Viro. Vertailtaessa investointikriteereitä toteutuneisiin investointeihin voidaan todeta, että suomalaiset investoijat eivät ole hyödyntäneet investoinneilla saatavia etuja kaikissa kohdemaissa.

The proportional distribution in a cooperative model with external opportunities

[cat] En aquest article es considera un problema de cooperació entre agents on cada agent realitza una contribució (diners, capital, treball, esforç) per tal d'obtenir un benefici comú a repartir. El repartiment proporcional respecte a les contribucions és una distribució que pertany al nucli del joc cooperatiu associat. A partir d'aquest model bàsic s'introdueix un agent extern que pot realitzar una determinada aportació que serveix per avaluar el potencial benefici de cada subcoalició d'agents si aquest nou agent finalment entrés. Aquesta anàlisi pot produir que el poder relatiu dels agents hagi variat. en concret s'avalua si la distribució proporcional és encara robusta des del punt de vista de la seva pertinença al conjunt de negociació. Amb aquest objectiu, analitzem el problema utilitzant el model de joc cooperatius amb estructura de coalició. Donat que, en general, la distribució proporcional, no pertany al conjunt de negociació, s'estudia una condició suficient per a que així sigui. També enunciem una condició necessària, i finalment es proposa una condició suficient que garanteix que el repartiment proporcional és la única distribució existent dins del conjunt de negociació.

Biogeochemical processes controlling oxygen and carbon isotopes of diatom silica in Late Glacial to Holocene lacustrine rhythmites

Biogeochemical cycles and sedimentary records in lakes are related to climate controls on hydrology and catchment processes. Changes in the isotopic imposition of the diatom frustules (δ 18 O diatom and δ 13 C diatom ) in lacustrine sediments can be used to reconstruct palaeoclimatic and palaeoenvironmental changes. The Lago Chungará (Andean Altiplano, 18°15 ′ S, 69°10 ′ W, 4520 masl) diatomaceous laminated sediments are made up of white and green multiannual rhythmites. White laminae were formed during short-term diatom super-blooms, and are composed almost exclusively of large-sized Cyclostephanos andinus.These diatoms bloom during mixing events when recycled nutrients from the bottom waters are brought to the surface and/or when nutrients are introduced from the catchment during periods of strong runoff. Conversely, the green laminae are thought to have been deposited over several years and are composed of a mixture of diatoms (mainly smaller valves of C. andinus and Discostella stelligera ) and organic matter. These green laminae reflect the lake's hydrological recovery from a status favouring the diatom super-blooms (white laminae) towards baseline conditions. δ 18 O diatom and δ 13 C diatom from 11,990 to 11,530 cal years BP allow us to reconstruct shifts in the precipitation/evaporation ratio and changes in the lake water dissolved carbon concentration, respectively. δ 18 O diatom values indicate that white laminae formation occurred mainly during low lake level stages, whereas green laminae formation generally occurred during high lake level stages. The isotope and chronostratigraphical data together suggest that white laminae deposition is caused by extraordinary environmental events. El Niño-Southern Oscillation and changes in solar activity are the most likely climate forcing mechanisms that could trigger such events, favouring hydrological changes at interannual-to-decadal scale. This study demonstrates the potential for laminated lake sediments to document extreme pluriannual events.

The proportional distribution in a cooperative model with external opportunities

[cat] En aquest article es considera un problema de cooperació entre agents on cada agent realitza una contribució (diners, capital, treball, esforç) per tal d'obtenir un benefici comú a repartir. El repartiment proporcional respecte a les contribucions és una distribució que pertany al nucli del joc cooperatiu associat. A partir d'aquest model bàsic s'introdueix un agent extern que pot realitzar una determinada aportació que serveix per avaluar el potencial benefici de cada subcoalició d'agents si aquest nou agent finalment entrés. Aquesta anàlisi pot produir que el poder relatiu dels agents hagi variat. en concret s'avalua si la distribució proporcional és encara robusta des del punt de vista de la seva pertinença al conjunt de negociació. Amb aquest objectiu, analitzem el problema utilitzant el model de joc cooperatius amb estructura de coalició. Donat que, en general, la distribució proporcional, no pertany al conjunt de negociació, s'estudia una condició suficient per a que així sigui. També enunciem una condició necessària, i finalment es proposa una condició suficient que garanteix que el repartiment proporcional és la única distribució existent dins del conjunt de negociació.

Carbon balance of Fibre-Based Package

Customers are more and more interested in the environmental impacts of the products they purchase. Different labels give the required environmental information to consumers and the labels might affect to the consuming decisions. The European Union has set a plan for sustainable consuming, which encourages industry and commerce to calculate carbon footprints for the products. A term “carbon footprint” means carbon dioxide emissions across the product lifecycle. In this thesis, carbon footprints are calculated for two different fibre-based packages. In the end, greenhouse gas emissions from fibre-package production are compared to greenhouse gas emissions from PET bottle production. The data for mill processes is exact and monitored in the mill. In addition, data was gathered from raw material and material suppliers, customers, official records, KCL-eco databases and literature. The data for PET bottle is sourced from literature. End-of-life operations affect greatly on the carbon footprint of a fibre-based package. The results show that the carbon footprint is smallest when used packages are recycled. Recycling saves also natural resources. If used packages are not recyclable for some reason, it is recommended to use them in energy production. Through waste incineration fossil fuels could be substituted and greenhouse gas emissions avoided.

Aluminium fouling and its impact on activated carbon based dioxin and furan removal in a wet scrubber at a co-incineration plant

Dioxins and furans, PCDD/Fs, are highly toxic substances formed in post combustion zones in furnaces. PCDD/F emissions are regulated by a waste incineration directive which relates also to co-incineration plants. Several observations of dioxin and furan enhancements in wet scrub- bers have been reported previously. This is thought to be due to the so-called "memory effect" which occurs when dioxins and furans absorb into plastic material in scrubbers and desorb when ambient circumstances alter significantly. At the co-incineration plant involved, dioxins and furans are controlled with a wet scrubber, the tower packing of which is made of plastic in which activated carbon particles are dispersed. This should avoid the memory effect and act as a dioxin and furan sink since dioxins and furans are absorbed irreversibly into the packing ma- terial. In this case, the tower packing in the scrubber is covered with a white layer that has been found to be mainly aluminium. The aim of this thesis was to determine the aluminium balance and the dioxin and furan behaviour in the scrubber and, thus, the impacts that the foul- ing has on dioxin and furan removal. The source of aluminium, reasons for fouling and further actions to minimize its impacts on dioxin and furan removal were also to be discovered. Measurements in various media around the scrubber and in fuels were made and a profile analysis of PCDD/F and mass balance calculations were carried out. PCDD/F content de- creased in the scrubber. The reduced PCDD/F was not discharged into scrubbing water. The removal mechanism seems to work in spite of the fouling, at least with low PCDD/F loads. Most of the PCDD/F in excess water originates from the Kymijoki River which is used as feeding water in the scrubber. Fouling turned out to consist mainly of aluminium hydroxides. Sludge combusted in the furnace was found to be a significant source of aluminium. Ways to minimize the fouling would be adjustment of pH to a proper lever, installation of a mechanical filter to catch the loose material from the scrubbing water and affecting the aluminium content of the sludge.

External urethral sphincter electromyography in asymptomatic women and the influence of the menstrual cycle.

OBJECTIVE: To investigate by electromyography (EMG), the presence of complex repetitive discharges (CRDs) and decelerating bursts (DBs) in the striated external urethral sphincter during the menstrual cycle in female volunteers with no urinary symptoms and complete bladder emptying. SUBJECTS AND METHODS: Healthy female volunteers aged 20-40 years, with regular menstrual cycles and no urinary symptoms were recruited. Volunteers completed a menstruation chart, urinary symptom questionnaires, pregnancy test, urine dipstick, urinary free flow and post-void ultrasound bladder scan. Exclusion criteria included current pregnancy, use of hormonal medication or contraception, body mass index of >35 kg/m(2) , incomplete voiding and a history of pelvic surgery. Eligible participants underwent an external urethral sphincter EMG, using a needle electrode in the early follicular phase and the mid-luteal phase of their menstrual cycles. Serum oestradiol and progesterone were measured at each EMG test. RESULTS: In all, 119 women enquired about the research and following screening, 18 were eligible to enter the study phase. Complete results were obtained in 15 women. In all, 30 EMG tests were undertaken in the 15 asymptomatic women. Sphincter EMG was positive for CRDs and DBs at one or both phases of the menstrual cycle in eight (53%) of the women. Three had CRDs and DBs in both early follicular and mid-luteal phases. Five had normal EMG activity in the early follicular phase and CRDs and DBs in the mid-luteal phase. No woman had abnormal EMG activity in the early follicular phase and normal activity in the luteal phase. There was no relationship between EMG activity and age, parity or serum levels of oestradiol and progesterone. CONCLUSIONS: CRDs and DB activity in the external striated urethral sphincter is present in a high proportion of asymptomatic young women. This abnormal EMG activity has been shown for the first time to change during the menstrual cycle in individual women. CRDs and DBs are more commonly found in the luteal phase of the menstrual cycle. The importance of CRDs and DBs in the aetiology of urinary retention in young women remains uncertain. The distribution and or quantity of abnormal EMG activity in the external urethral sphincter may be important. In a woman with urinary retention the finding of CRDs and DBs by needle EMG does not automatically establish Fowler's syndrome as the explanation for the bladder dysfunction. Urethral pressure profilometry may be helpful in establishing a diagnosis. Opiate use and psychological stress should be considered in young women with urinary retention.

Pathogenic attack and carbon reallocation in soybean leaves (Glycine max. L.): Reinitiation of the glyoxylate cycle as a defence reaction

Pathogenic attack by the fungus Botrytis cinerea (primary pathogen) on soybean leaves (Glycine max. L.; cv. Maple arrow) results in a hypersensitive response (necrotising infected leaves), in the establishment of local acquired resistance, as well as in the systemic induction of genes coding for pathogenesis-related proteins. It now appears that, concomitantly with these already well documented defence reactions, the pathogenic attack also induces the carbon reallocation mechanism based on the reinitiation of the glyoxylate cycle (pseudo-senescence of the infected leaves).

External Validation of the Prestroke Independence, Sex, Age, National Institutes of Health Stroke Scale (ISAN) Score for Predicting Stroke-Associated Pneumonia in the Athens Stroke Registry.

BACKGROUND AND PURPOSE: The Prestroke Independence, Sex, Age, National Institutes of Health Stroke Scale (ISAN) score was developed recently for predicting stroke-associated pneumonia (SAP), one of the most common complications after stroke. The aim of the present study was to externally validate the ISAN score. METHODS: Data included in the Athens Stroke Registry between June 1992 and December 2011 were used for this analysis. Inclusion criteria were the availability of all ISAN score variables (prestroke independence, sex, age, National Institutes of Health Stroke Scale score). Receiver operating characteristic curves and linear regression analyses were used to determine the discriminatory power of the score and to assess the correlation between actual and predicted pneumonia in the study population. Separate analyses were performed for patients with acute ischemic stroke (AIS) and intracerebral hemorrhage (ICH). RESULTS: The analysis included 3204 patients (AIS: 2732, ICH: 472). The ISAN score demonstrated excellent discrimination in patients with AIS (area under the curve [AUC]: .83 [95% confidence interval {CI}: .81-.85]). In the ICH group, the score was less effective (AUC: .69 [95% CI: .63-.74]). Higher-risk groups of ISAN score were associated with an increased relative risk of SAP; risk increase was more prominent in the AIS population. Predicted pneumonia correlated very well with actual pneumonia (AIS group: R(2) = .885; β-coefficient = .941, P < .001; ICH group: R(2) = .880, β-coefficient = .938, P < .001). CONCLUSIONS: In our external validation in the Athens Stroke Registry cohort, the ISAN score predicted SAP very accurately in AIS patients and demonstrated good discriminatory power in the ICH group. Further validation and assessment of clinical usefulness would strengthen the score's utility further.

'A pilot study to investigate external urethral sphincter electromyographic activity and the influence of hormonal changes in the menstrual cycle'

But de l'étude Un enregistrement spécifique EMG du sphincter strié urétral avec décharges répétitives et complexes ainsi que salves de décélération a été décrit comme pathognomonique du syndrome de Fowler, un trouble de la relaxation du sphincter strié urétral chez la femme jeune responsable d'une retention urinaire. Nous avons souhaité étudier la présence de cet enregistrement EMG spécifique chez la femme asymptomatique, ceci à différents moments du cycle menstruel. Matériel et Méthode Nous avons recruté des femmes volontaires saines âgées entre 20 et 40 ans, ayant un cycle hormonal régulier, et ne présentant aucun symptôme urinaire. Les critères d'exclusion étaient la presence d'une dysfonction mictionnelle, d'une infection urinaire, la grossesse, la prise d'une thérapie hormonale ou d'hormone contraceptive, une obésité et des antécédants d'intervention pelvienne. Nous avons procédé à deux enregistrements EMG du sphincter strié urétral des participantes éligibles, utilisant une aiguille concentrique, ceci dans la première phase du cycle (phase folliculaire) et dans la dernière phase du cycle (phase lutéale). Les taux sériques de progestérone et d'oestrogène étaient mesurés à chaque enregistrement. Résultats 15 participantes ont complété l'étude. L' enregistrement EMG du sphincter a été positif avec présence de décharges répétitives et de salves de décélération lors d'une ou des deux phases du cycle menstruel chez 8 participantes (53%). Trois participantes présentaient cet enregistrement spécifique lors des deux phases du cycle et cinq participantes présentaient cet enregistrement spécifique lors de la phase lutéale uniquement. Aucune femme ne présentait cet enregistrement spécifique en début de cycle uniquement. Il n'y avait pas de relation avec l'âge, la parité ou les taux hormonaux. Conclusions L'enregistrement EMG spécifique du sphincter strié urétral, avec décharges répétitives et salves de décélération, se retrouve chez une proportion élevée de femmes asymptomatiques. Il a été montré que ce tracé change lors du cycle menstruel, en étant retrouvé plus fréquemment dans la dernière phase du cycle. L'importance de cet enregistrement EMG dans l'étiologie de la retention urinaire de la femme jeune reste à éclaircir. Nous devons considérer que sa présence ne pose pas automatiquement un diagnostic de syndrome de Fowler chez la femme en rétention urinaire.

Improving coronary artery bypass graft durability: use of the external saphenous vein graft support.

Coronary bypass grafting remains the best option for patients suffering from multivessel coronary artery disease, and the saphenous vein is used as an additional conduit for multiple complete revascularizations. However, the long-term vein graft durability is poor, with almost 75% of occluded grafts after 10 years. To improve the durability, the concept of an external supportive structure was successfully developed during the last years: the eSVS Mesh device (Kips Bay Medical) is an external support for vein graft made of weft-knitted nitinol wire into a tubular form with an approximate length of 24 cm and available in three diameters (3.5, 4.0 and 4.5 mm). The device is placed over the outer wall of the vein and carefully deployed to cover the full length of the graft. The mesh is flexible for full adaptability to the heart anatomy and is intended to prevent kinking and dilatation of the vein in addition to suppressing the intima hyperplasia induced by the systemic blood pressure. The device is designed to reduce the vein diameter of about 15-20% at most to prevent the vein radial expansion induced by the arterial blood pressure, and the intima hyperplasia leading to the graft failure. We describe the surgical technique for preparing the vein graft with the external saphenous vein graft support (eSVS Mesh) and we share our preliminary clinical results.

Resultate und ausser- gewöhnliche Komplikationen der Chirurgie der Gehörgangexostosen [Results and extraordinary complications of surgery for exostoses of the external auditory canal].

We present a retrospective study on 22 operations of exostosis of the external auditory canal in 20 patients. 8 patients were passionated by water sports. The most frequent indication for surgery (13 operations) was recurrent external otitis or ceruminal obstruction. In 7 cases the need for a wider access to the middle ear indicated surgery. Surgery was usually performed as an outpatient procedure, maximum hospitalization was 3 days. The mean healing period was 6 (3-10) weeks. Mean follow up was 43 (3-110) months. There were no severe intraoperative complications such as facial paresis, lesions of the ossicles or of the inner ear. As intraoperative complications we found 2 perforations of the tympanic membrane, 2 expositions of the capsule of the mandibular joint, one of which was followed by chronic pain. As postoperative complications we found an early soft tissue stenosis of the external auditory canal and one late soft tissue stenosis which recurred after revision surgery. No recurrence of exostosis was seen. We describe an up to now unknown complication: the appearance of bilateral petrositis caused by staphylococcus epidermidis after bilateral surgery in an otherwise healthy patient. This study confirms that severe complications are rare, minor ones however relatively common. And that also minor complications may have a troublesome follow. Therefore and because of the potential of severe complications indication for surgery must be made cautiously and risks of the operation must not be underestimated.