Effects of solar activity and climate variability on large floods in Switzerland

The paper presents the variability of major floods in Switzerland for the period 1800-2008 from a summer index (INU). The index is constructed from the damage caused by flooding, with the aim of establishing the possible influence of the solar and climate variability on the major floods. The coincidence of flood-rich periods with those observed in other regions of different climate and fluvial regimes suggests that climate forcings and changes in the general circulation of the atmosphere are those who govern the appearance of these high-frequency temporal clusters.

Plasmid DNA damage induced by singlet molecular oxygen released from the naphthalene endoperoxide DHPNO2 and photoactivated methylene blue

To investigate oxidative lesions and strand breaks induction by singlet molecular oxygen (¹O2), supercoiled-DNA plasmid was treated with thermo-dissociated DHPNO2 and photoactivated-methylene blue. DNA lesions were detected by Fpg that cleaves DNA at certain oxidized bases, and T4-endoV, which cleaves DNA at cyclobutane pyrimidine dimers and apurinic/apyrimidinic (AP) sites. These cleavages form open relaxed-DNA structures, which are discriminated from supercoiled-DNA. DHPNO2 or photoactivated-MB treatments result in similar plasmid damage profile: low number of single-strand breaks or AP-sites and high frequency of Fpg-sensitive sites; confirming that base oxidation is the main product for both reactions and that ¹O2 might be the most likely intermediate that reacts with DNA.

Ocorrência de Pratylenchus brachyurus e Meloidogyne incognita na cultura do algodoeiro no Estado do Mato Grosso

In a survey carried out in the state of Mato Grosso, Brazil, the lesion nematode, Pratylenchus brachyurus, and the root-knot nematode, Meloidogyne incognita, were found, respectively, in 94% and 3.7% of a total of 623 root and soil samples representing 21,793 ha. No visible aboveground symptoms in cotton (Gossypium hirsutum) plants infected by P. brachyurus were observed, except for typical root lesions. In contrast, plants with M. incognita usually exhibited pronounced symptoms of damage. The high frequency (94%) of P. brachyurus was unexpected and is of concern considering the fact that soybean (Glycine max) and corn (Zea mays), are both susceptible to this nematode and are used in crop rotation programs.

Tasasähkönjakeluverkon vaihtosuuntaaja galvaanisella erotuksella

Suomessa sähkönjakeluverkko koostuu pääasiassa 20 kV ja 400 V jännitetasoista. Tällöin sähkö viedään lähelle kuluttajia suuremmalla jännitetasolla ja muunnetaan alhaisemmaksi lähellä asiakkaita. Haittapuolena on se, että haja-asutusalueilla jakelumuuntajien määrä kasvaa suureksi, koska ne täytyy sijoittaa lähelle kuluttajaa. Vaihtoehtona on toteuttaa osa sähkönjakelusta tasajännitteellä, jolloin tehollinen jännite olisi suurempi. Tällöin sähköä voitaisiin siirtää pidempiä matkoja ilman, että asiakaskohtaisia tai muutaman asiakkaan kattavia 20 kV siirtolinjoja tarvitsisi käyttää. Tämä taasen edellyttää asiakaskohtaisien vaihtosuuntaajien käyttöä. Tässä työssä esiteltävällä 1 kVA vaihtosuuntaajalla muodostetaan tasasähköjakeluverkosta saatavasta 750 V tasasähköstä yksivaiheista (230 VRMS, 50 Hz) verkkojännitettä. Laite on suunniteltu toteuttamaan galvaaninen erotus mahdollisimman hyvän hyötysuhteen puitteissa. Vaihtosuuntaaja on toteutettu käyttämällä resonanssikonvertteria, joka vaihtosuuntaa jakelujännitteen korkeataajuiseksi vaihtojännitteeksi. Tämän jälkeen toteutetaan galvaaninen erotus käyttäen suurtaajuusmuuntajaa. Tätä seuraa syklokonvertteri, joka pulssintiheysmodulaatiota soveltaen muodostaa lähtöjännitteen. Tämä suodatetaan lopuksi LC- alipäästösuotimella säröltään standardin mukaiseksi. Laite on jaettu työssä kolmeen osaan, joista jokaisen toiminta on selitetty ja simuloitu itsenäisesti. Lopussa koko järjestelmä on simuloitu yhtenä kokonaisuutena. Hyötysuhteeksi arvioitiin karkeasti 94 % ja lopullisista tuloksista voidaan päätellä, että laitteen toteuttaminen prototyypiksi voisi olla kannattavaa.

Current-phase relation in graphene Josephson junction

In this thesis, we present the results of high-frequency measurements on superconductor-graphene-superconductor junctions. We obtained the relation between the supercurrent through the junction and the superconducting phase. The relation allowed us to extract true critical current and to determine the transport regime of graphene in our SGS-junction samples at the Dirac point and away from it. An experimental temperature dependence of the current-phase relation is presented. We have calculated theoretical supercurrent-phase relation in the case of ballistic and diffusive junction. For the diffusive case, we have considered short and long limits where the coherence length is larger or smaller than the sample length, respectively.

Reading Development During Elementary School Years. Evidence from Eye Movements

The present dissertation examined reading development during elementary school years by means of eye movement tracking. Three different but related issues in this field were assessed. First of all, the development of parafoveal processing skills in reading was investigated. Second, it was assessed whether and to what extent sublexical units such as syllables and morphemes are used in processing Finnish words and whether the use of these sublexical units changes as a function of reading proficiency. Finally, the developmental trend in the speed of visual information extraction during reading was examined. With regard to parafoveal processing skills, it was shown that 2nd graders extract letter identity information approx. 5 characters to the right of fixation, 4th graders approx. 7 characters to the right of fixation, and 6th graders and adults approx. 9 characters to the right of fixation. Furthermore, it was shown that all age groups extract more parafoveal information within compound words than across adjectivenoun pairs of similar length. In compounds, parafoveal word information can be extracted in parallel with foveal word information, if the compound in question is of high frequency. With regard to the use of sublexical units in Finnish word processing, it was shown that less proficient 2nd graders use both syllables and morphemes in the course of lexical access. More proficient 2nd graders as well as older readers seem to process words more holistically. Finally, it was shown that 60 ms is enough for 4th graders and adults to extract visual information from both 4-letter and 8-letter words, whereas 2nd graders clearly needed more than 60 ms to extract all information from 8- letter words for processing to proceed smoothly. The present dissertation demonstrates that Finnish 2nd graders develop their reading skills rapidly and are already at an adult level in some aspects of reading. This is not to say that there are no differences between less proficient (e.g., 2nd graders) and more proficient readers (e.g., adults) but in some respects it seems that the visual system used in extracting information from the text is matured by the 2nd grade. Furthermore, the present dissertation demonstrates that the allocation of attention in reading depends much on textual properties such as word frequency and whether words are spatially unified (as in compounds) or not. This flexibility of the attentional system naturally needs to be captured in word processing models. Finally, individual differences within age groups are quite substantial but it seems that by the end of the 2nd grade practically all Finnish children have reached a reasonable level of reading proficiency.

Galvaanisen erotuksen toteuttaminen tasavirtasähkönjakelun asiakaspäätelaitteessa

Suomessa sähkönjakeluverkon pääasialliset jännitetasot ovat 20 kV ja 400 V. 20 kV jännitetasolla sähkö viedään lähelle kuluttajia ja muunnetaan pienemmäksi lähellä asiakkaita. Haittapuolena on se, että 20 kV avojohtosähkönsiirtoverkko on hyvin vika-altis ja usein yhden haaran vikaantuessa monta muutakin jää ilman sähköä. Lisäksi hintavien ja suurien jakelumuuntajien määrä on suuri. Vaihtoehtona on toteuttaa osa sähkönjakelusta tasajännitteellä, jolloin tehollinen pienjännite olisi 400 V:a suurempi. Tällöin sähköä voitaisiin siirtää pidempiä matkoja ilman, että asiakaskohtaisia tai muutaman asiakkaan kattavia 20 kV siirtolinjoja tarvitsisi käyttää. Tämä edellyttää vaihtosuuntauksen toteuttamista kuluttajan päässä. Tässä työssä esiteltävällä 1 kVA:n tehoisella vaihtosuuntaajalla muodostetaan tasasähköjakeluverkosta saatavasta 750 V tasasähköstä yksivaiheista (230 VRMS, 50 Hz) verkkojännitettä. Laite on suunniteltu toteuttamaan galvaaninen erotus mahdollisimman hyvällä hyötysuhteella. Suurtaajuusmuuntajan mitoitus mahdollisimman hyvälle hyötysuhteelle on haastava tehtävä, koska vaatimuksia sille asettavat sekä syöttävä resonanssikonvertteri että syötettävä syklokonvertteri. Mitoituksessa on pyrittävä löytämään mahdollisimman hyvä hyötysuhde kustannusten ja toteutettavuuden suhteen.

Automatisoidun kaupankäynnin vaikutukset markkinatehokkuuteen

Tutkielmassa selvitettiin algoritmisen kaupankäynnin vaikutuksia markkinatehokkuuteen. Se toteutettiin kirjallisuuskatsauksena tuoreimmista tutkimuksista. Aluksi esitellään algoritmisten kaupankäyntijärjestelmien rakenne ja tapa toimia, jonka jälkeen aiemmat tutkimukset käydään läpi. Tulokset osoittavat, että algoritminen kaupankäynti on parantanut markkinatehokkuutta hinnanmuodostuksen ja likviditeetin osalta. Merkittäviä negatiivisia vaikutuksia ei huomattu.

Water storage in wetted strips under irrigated coffee trees with different criteria of irrigation management

The increasing demand for water resources accentuates the need to reduce water waste through a more appropriate irrigation management. In the particular case of irrigated coffee planting, which in recent years presented growth with the predominance of drip irrigation, the improvement of drip irrigation management techniques is a necessity. The proper management of drip irrigation depends on the knowledge of the spatial pattern of soil moisture distribution inside the wetted strip formed under the irrigation lines. In this study, grids of 24 tensiometers were used to determine the water storage within the wetted strip formed under drippers, with a 3.78 L h-1 discharge, evenly spaced by 0.4 m, subjected to two different management criteria (fixed irrigation interval and 60 kPa tension). Estimates of storage based on a one-dimensional analysis, that only considers depth variations, were compared with two-dimensional estimates. The results indicate that for high-frequency irrigation the one-dimensional analysis is not appropriate. However, under less frequent irrigation, the two-dimensional analysis is dispensable, being the one-dimensional sufficient for calculating the water volume stored in the wetted strip.

Tasasähkönjakeluverkon vaihtosuuntaajan pulssintiheysmoduloidun pääteasteen ja prototyypin toteutus

Työssä esiteltävä laite on osa DC-AC hakkuria, jolla muodostetaan 750 V tasajännitteestä yksivaiheista (230 VRMS, 50 Hz) galvaanisesti erotettua verkkojännitettä. Tasajännite muunnetaan resonanssikonvertterilla korkeataajuiseksi vaihtojännitteeksi, joka johdetaan erotusmuuntajaan. Galvaanisen erotuksen jälkeen korkeataajuisesta vaihtojännitteestä muodostetaan suoraan verkkotaajuista vaihtojännitettä työssä esiteltävällä syklokonvertterilla. Suunnittelussa on pyritty minimoimaan häviöt mahdollisimman tarkkaan, jotta laite olisi kilpailukykyinen ei-galvaanisesti erottavien konverttereiden kanssa. Tämä on toteutettu käyttämällä mahdollisimman vähän komponentteja virran kulkureitillä sekä soveltamalla pehmeää kytkentää kaikissa tilanteissa. Lopuksi esitellään prototyyppi, jonka tarkoitus oli selvittää laitteen toiminta ja ongelmakohdat käytännössä.

Anaplasma marginale infection in cattle from south-western Amazonia

The present study provides the first epidemiological data regarding infection by Anaplasma marginale in cattle reared in south-western Brazilian Amazonia. One simple procedure was adapted for the extraction of DNA from blood clots collected in seven microregions of Rondônia State and two mesoregions of Acre State. PCR method was used to asses the frequency of A. marginale infections in 4 to12-month-old cattle. The cattle infection was investigated by polymerase chain reaction (PCR) using the specific primer "msp5" for A. marginale. The DNA amplifications revealed that the mean frequency of A. marginale infection was 98.6% (1,627/1,650) in samples from Rondonia, and 92.87% (208/225) in samples from Acre. The high frequency of A. marginale infections in 4 to 12-month-old cattle indicate a situation of enzootic stability in the studied areas and are comparable to those detected by immunodiagnosis in different endemic regions in Brazil. The DNA extraction of clotted blood method described here can be used for epidemiological studies on anaplasmosis and other bovine hemoparasites.

Detection of virulence-associated genes of Pasteurella multocida isolated from cases of fowl cholera by multiplex-PCR

The current systems of breeding poultry, based on high population density, increase the risk of spreading pathogens, especially those causing respiratory diseases and those that have more than one host. Fowl Cholera (FC) is one such pathogen, and even though it represents one of several avian diseases that should be considered in the differential diagnosis of notifiable diseases that present with sudden death, the pathogenesis and virulence factors involved in FC are still poorly understood. The objective of this study was to investigate twelve genes related to virulence in 25 samples of Pasteurella multocida isolated from FC cases in the southern region of Brazil through the development of multiplex PCR protocols. The protocols developed were capable of detecting all of the proposed genes. The ompH, oma87, sodC, hgbA, hgbB, exBD-tonB and nanB genes were present in 100% of the samples (25/25), the sodA and nanH genes were present in 96% (24/25), ptfA was present in 92% (23/25), and pfhA was present in 60% (15/25). Gene toxA was not identified in any of the samples studied (0/25). Five different genetic profiles were obtained, of which P1 (negative to toxA) was the most common. We concluded that the multiplex-PCR protocols could be useful tools for rapid and simultaneous detection of virulence genes. Despite the high frequency of the analyzed genes and the fact that all samples belonged to the same subspecies of P. multocida, five genetic profiles were observed, which should be confirmed in a study with a larger number of samples.

Identification and antimicrobial resistance of members from the Enterobacteriaceae family isolated from canaries (Serinus canaria)

Abstract: The Enterobacteriaceae family contains potentially zoonotic bacteria, and their presence in canaries is often reported, though the current status of these in bird flocks is unknown. Therefore, this study aimed to identify the most common genera of enterobacteria from canaries (Serinus canaria) and their antimicrobial resistance profiles. From February to June of 2013, a total of 387 cloacal swab samples from eight domiciliary breeding locations of Fortaleza city, Brazil, were collected and 58 necropsies were performed in canaries, which belonged to the Laboratory of Ornithological Studies. The samples were submitted to microbiological procedure using buffered peptone water and MacConkey agar. Colonies were selected according to their morphological characteristics on selective agar and submitted for biochemical identification and antimicrobial susceptibility. A total of 61 isolates were obtained, of which 42 were from cloacal swabs and 19 from necropsies. The most isolated bacteria was Escherichia coli with twenty five strains, followed by fourteen Klebsiellaspp., twelve Enterobacterspp., seven Pantoea agglomerans, two Serratiaspp. and one Proteus mirabilis. The antimicrobial to which the strains presented most resistance was sulfonamides with 55.7%, followed by ampicillin with 54.1% and tetracycline with 39.3%. The total of multidrug-resistant bacteria (MDR) was 34 (55.7%). In conclusion, canaries harbor members of the Enterobacteriaceae family and common strains present a high antimicrobial resistance rate, with a high frequency of MDR bacteria.

Vibration analysis for Bearing outer race condition diagnostics

This paper investigates defect detection methodologies for rolling element bearings through vibration analysis. Specifically, the utility of a new signal processing scheme combining the High Frequency Resonance Technique (HFRT) and Adaptive Line Enhancer (ALE) is investigated. The accelerometer is used to acquire data for this analysis, and experimental results have been obtained for outer race defects. Results show the potential effectiveness of the signal processing technique to determine both the severity and location of a defect. The HFRT utilizes the fact that much of the energy resulting from a defect impact manifests itself in the higher resonant frequencies of a system. Demodulation of these frequency bands through use of the envelope technique is then employed to gain further insight into the nature of the defect while further increasing the signal to noise ratio. If periodic, the defect frequency is then present in the spectra of the enveloped signal. The ALE is used to enhance the envelope spectrum by reducing the broadband noise. It provides an enhanced envelope spectrum with clear peaks at the harmonics of a characteristic defect frequency. It is implemented by using a delayed version of the signal and the signal itself to decorrelate the wideband noise. This noise is then rejected by the adaptive filter that is based upon the periodic information in the signal. Results have been obtained for outer race defects. They show the effectiveness of the methodology to determine both the severity and location of a defect. In two instances, a linear relationship between signal characteristics and defect size is indicated.

Kiteen mekaanisten värähtelyjen vaimentaminen takaisinkytkennällä

Pulseri on laite, joka tuottaa noin 10 MHz:n taajuudella olevan sähköisen pulssin, joka ohjataan kiteeseen. Kide lähettää korkeataajuuksisen ääniaallon ja toimii samalla vastaanottimena kaikuna heijastuneille ääniaalloille. Kide ja membraanikalvo ovat vedessä. Ääniaalto heijastuu takaisin suodatusmembraanikalvosta, jolla on tarkoitus erotella epäpuhtauksia. Membraanikalvo ja kide ovat millimetrin etäisyydellä toisistaan ja ääniaalloilla kestää noin 1,3 mikrosekuntia kulkea kiteestä membraanikalvon pinnalle ja siitä kaikuna takaisin kiteeseen. Saadaksemme luotettavia tuloksia ääniaallon kulkuajasta, kiteen tulee olla värähtelemättömässä tilassa silloin, kun kaikuna palaava pulssi saapuu takaisin. Työssä keskitytään kiteen vaimentamiseen mahdollisimman nopeasti lähetetyn pulssin jälkeen ja siihen liittyviin ongelmiin.