Growth of red and green strains of the tropical agarophyte Gracilaria cornea J. Agardh (Gracilariales, Rhodophyta) in laboratory

Gracilaria cornea J. Agardh is an important agarophyte occurring in the western Atlantic Ocean. Green colour individuals of G. cornea were found in a natural population, growing next to red individuals, which were more common. Due to the importance of colour strains in genetic and intraspecific variability studies, this work aimed to characterize the red and green strains evaluating different nutritional and light conditions. Red and green gametophytes were cultivated at 14:10 light: dark cycle, with alternating aeration periods of 30 min. Two different enriched solutions were tested: von Stosch (VSS) at concentrations reduced to 12.5% and 25%; and Provasoli (PES) at concentrations reduced to 25% and 50%, and 100%. Red and green gametophytes were cultivated at the irradiance of 45 mumol photons m-2 s-1. In another experiment utilizing PES 100%, two sources of light (Osram 40 W daylight fluorescent tubes and Sylvania Designer 3,500 tubes) were tested at irradiances of 90 and 180 mumol photons m-2 s-1. Growth rates (GR) were evaluated for five weeks. Gametophytes developed few branches and reproductive structures were not induced. Differences were not observed between GR of red and green strains in the conditions tested. GR were higher in VSS 12.5% (8.4% day-1) than in 25% (7.1% day-1), suggesting an adaptation of the species to low nutrient concentrations. GR were higher at 180 (9.0% day-1) than at 90 mumol photons m-2 s-1 (6.3% day-1). These results suggest that G. cornea should be cultivated in laboratory at high irradiances and low nutrient concentrations. These data will be useful in future genetic and physiological studies of the species.

Hitsauslankojen kallistuskulmien vaikutus hitsausliitoksen ominaisuuksiin S355-rakenneteräksen tandem-MAG-pienahitsauksessa

Tämä kandidaatintyö on tutkimus hitsauslankojen kallistuskulmien vaikutuksesta hitsausliitoksen ominaisuuksiin tandem-MAG-pienahitsauksessa S355-rakenneteräkselle. Kokeellinen osuus suoritettiin Lappeenrannan teknillisen yliopiston hitsaustekniikan laboratoriossa jatkotutkimuksena Binbin Yanin diplomityölle ”Influence of wire configurations of welding S355 structural steel with tandem GMAW”. Tutkimuksen tavoitteena on määrittää tandem-MAG-hitsauksessa käytettyjen hitsauslankojen kallistuskulmien vaikutus hitsausliitoksen ominaisuuksiin. Teoriaosuuden tavoitteena on selvittää myös muiden hitsausparametrien vaikutus hitsausliitoksen ominaisuuksiin sekä perehtyä hitsisulan käyttäytymiseen terästen tandem-MAG-hitsauksessa.

A laboratory cage for foster nursing newborn mice

We describe a cage to be used for foster nursing in order to guarantee that original mother's colostrum is not ingested by the newborn mice. A common (30.5 cm x 19.5 cm x 12.0 cm) mouse cage was fitted with a wire net tray with a mesh (1 cm x 1 cm), which divides the cage into an upper and a lower compartment. Mice born to females placed in the upper compartment pass through the mesh and fall into the lower compartment, where another lactating female with one or two of its own pups are. Of a total of 28 newborn mice of C3H/He and Swiss strains, 23 were successfully fostered. Important observations are presented to show that this is a valuable alternative for foster studies without great suffering on the part of the female.

K-liitoksen epäkeskeisen tuennan aiheuttaman sekundäärisen momentin määritys

Työssä on tutkittu laboratoriokokeen ja elementtimenetelmän avulla eri geometrioiden vaikutusta sekundääriseen momentin syntymiseen K-liitoksella. Kokeen liitos on tehty S700-lujuusluokan Ruukin Optim 700 plus MH nelikulmaisista rakenneputkista (RHS). Elementtimalleissa on käytetty geometrista ja materiaalista epälineaarisuutta ennustamaan liitoksen muodonmuutoskykyä ja laskennallista kestävyyttä. Liitoksen elementtimalleissa muutettavia geometrioita ovat: vapaaväli, uumasauvan ja paarteen välinen kulma, paarteen seinämän paksuus, liitoksen eksentrisyys ja uumasauvan ja paarteen leveyden suhde. Laboratoriokokeen liitoksen vetouumasauvassa vaikuttava sekundäärisen momentin aiheuttama jännitys on noin 25 % vetouumasauvan myötörajasta. Suurin sekundäärinen momentti syntyy, kun vapaaväliä pienennetään ja uumasauvaa kavennetaan paarteeseen nähden. Eurocode 3:n mitoitusohjeita voidaan elementtimallien perusteella soveltaa tietyille geometrioille turvallisesti.

Pressurized hot water flow-through extraction of birch wood

Effective processes to fractionate the main compounds in biomass, such as wood, are a prerequisite for an effective biorefinery. Water is environmentally friendly and widely used in industry, which makes it a potential solvent also for forest biomass. At elevated temperatures over 100 °C, water can readily hydrolyse and dissolve hemicelluloses from biomass. In this work, birch sawdust was extracted using pressurized hot water (PHWE) flow-through systems. The hypothesis of the work was that it is possible to obtain polymeric, water-soluble hemicelluloses from birch sawdust using flow-through PHW extractions at both laboratory and large scale. Different extraction temperatures in the range 140–200 °C were evaluated to see the effect of temperature to the xylan yield. The yields and extracted hemicelluloses were analysed to obtain sugar ratios, the amount of acetyl groups, furfurals and the xylan yields. Higher extraction temperatures increased the xylan yield, but decreased the molar mass of the dissolved xylan. As the extraction temperature increased, more acetic acid was released from the hemicelluloses, thus further decreasing the pH of the extract. There were only trace amounts of furfurals present after the extractions, indicating that the treatment was mild enough not to degrade the sugars further. The sawdust extraction density was increased by packing more sawdust in the laboratory scale extraction vessel. The aim was to obtain extracts with higher concentration than in typical extraction densities. The extraction times and water flow rates were kept constant during these extractions. The higher sawdust packing degree decreased the water use in the extractions and the extracts had higher hemicellulose concentrations than extractions with lower sawdust degrees of packing. The molar masses of the hemicelluloses were similar in higher packing degrees and in the degrees of packing that were used in typical PHWE flow-through extractions. The structure of extracted sawdust was investigated using small angle-(SAXS) and wide angle (WAXS) x-ray scattering. The cell wall topography of birch sawdust and extracted sawdust was compared using x-ray tomography. The results showed that the structure of the cell walls of extracted birch sawdust was preserved but the cell walls were thinner after the extractions. Larger pores were opened inside the fibres and cellulose microfibrils were more tightly packed after the extraction. Acetate buffers were used to control the pH of the extracts during the extractions. The pH control prevented excessive xylan hydrolysis and increased the molar masses of the extracted xylans. The yields of buffered extractions were lower than for plain water extractions at 160–170 °C, but at 180 °C yields were similar to those from plain water and pH buffers. The pH can thus be controlled during extraction with acetate buffer to obtain xylan with higher molar mass than those obtainable using plain water. Birch sawdust was extracted both in the laboratory and pilot scale. The performance of the PHWE flow-through system was evaluated in the laboratory and the pilot scale using vessels with the same shape but different volumes, with the same relative water flow through the sawdust bed, and in the same extraction temperature. Pre-steaming improved the extraction efficiency and the water flow through the sawdust bed. The extracted birch sawdust and the extracted xylan were similar in both laboratory and pilot scale. The PHWE system was successfully scaled up by a factor of 6000 from the laboratory to pilot scale and extractions performed equally well in both scales. The results show that a flow-through system can be further scaled up and used to extract water-soluble xylans from birch sawdust. Extracted xylans can be concentrated, purified, and then used in e.g. films and barriers, or as building blocks for novel material applications.

Changes in clinical and laboratory findings at the time of diagnosis of primary hyperparathyroidism in a University Hospital in São Paulo from 1985 to 2002

In contrast to most developed countries, most patients with primary hyperparathyroidism in Brazil are still symptomatic at diagnosis. However, we have been observing a change in this pattern, especially in the last few years. We evaluated 104 patients, 77 females and 27 males aged 11-79 years (mean: 54.4 years), diagnosed between 1985 and 2002 at a University Hospital. Diagnosis was made on the basis of clinical findings and of high total and/or ionized calcium levels, high or inappropriate levels of intact parathyroid hormone and of surgical findings in 80 patients. Patients were divided into three groups, i.e., patients diagnosed from 1985 to 1989, patients diagnosed from 1990 to 1994, and patients diagnosed from 1995 to 2002. The number of new cases diagnosed/year increased from 1.8/year in the first group to 6.0/year in the second group and 8.1/year in the third group. The first group comprised 9 patients (mean serum calcium ± SD, 13.6 ± 1.6 mg/dl), 8 of them (88.8%) defined as symptomatic. The second group comprised 30 patients (mean calcium ± SD, 12.2 ± 1.63 mg/dl), 22 of them defined as symptomatic (73.3%). The third group contained 65 patients (mean calcium 11.7 ± 1.1 mg/dl), 34 of them symptomatic (52.3%). Patients from the first group tended to be younger (mean ± SD, 43.0 ± 15 vs 55.1 ± 14.4 and 55.7 ± 17.3 years, respectively) and their mean serum calcium was significantly higher (P < 0.05). All of symptomatic patients independent of group had higher serum calcium levels (12.4 ± 1.53 mg/dl, N = 64) than asymptomatic patients (11.4 ± 1.0 mg/dl, N = 40). Our data showed an increase in the percentage of asymptomatic patients over the years in the number of primary hyperparathyroidism cases diagnosed. This finding may be due to an increased availability of diagnostic methods and/or to an increased awareness about the disease.

Gender and age differences in polysomnography findings and sleep complaints of patients referred to a sleep laboratory

Our objective was to examine the effet of gender on the sleep pattern of patients referred to a sleep laboratory. The data (questionnaires and polysomnographic recordings) were collected from a total of 2365 patients (1550 men and 815 women). The polysomnography permits an objective assessment of the sleep pattern. We included only polysomnography exams obtained with no more than one recording system in order to permit normalization of the data. Men had a significantly higher body mass index than women (28.5 ± 4.8 vs 27.7 ± 6.35 kg/m²) and had a significantly higher score on the Epworth Sleepiness Scale (10.8 ± 5.3 vs 9.5 ± 6.0), suggesting daytime sleepiness. Women had a significantly higher sleep latency than men, as well as a higher rapid eye movement (REM) latency. Men spent more time in stages 1 (4.6 ± 4.1 vs 3.9 ± 3.8) and 2 (57.0 ± 10.5 vs 55.2 ± 10.1) of non-REM sleep than women, whereas women spent significantly more time in deep sleep stages (3 and 4) than men (22.6 ± 9.0 vs 19.9 ± 9.0). The apnea/hypopnea and arousal indexes were significantly higher and more frequent in men than in women (31.0 ± 31.5 vs 17.3 ± 19.7). Also, periodic leg movement index did not differ significantly between genders, but rather differed among age groups. We did not find significant differences between genders in the percentage of REM sleep and sleep efficiency. The results of the current study suggest that there are specific gender differences in sleep pattern.

Study of the comprehension of the scientific method by members of a university health research laboratory

In Brazil, scientific research is carried out mainly at universities, where professors coordinate research projects with the active participation of undergraduate and graduate students. However, there is no formal program for the teaching/learning of the scientific method. The objective of the present study was to evaluate the comprehension of the scientific method by students of health sciences who participate in scientific projects in an academic research laboratory. An observational descriptive cross-sectional study was conducted using Edgar Morin complexity as theoretical reference. In a semi-structured interview, students were asked to solve an abstract logical puzzle - TanGram. The collected data were analyzed using the hermeneutic-dialectic analysis method proposed by Minayo and discussed in terms of the theoretical reference of complexity. The students’ concept of the scientific method is limited to participation in projects, stressing the execution of practical procedures as opposed to scientific thinking. The solving of the TanGram puzzle revealed that the students had difficulties in understanding questions and activities focused on subjects and their processes. Objective answers, even when dealing with personal issues, were also reflected on the students’ opinions about the characteristics of a successful researcher. Students’ difficulties concerning these issues may affect their scientific performance and result in poorly designed experiments. This is a preliminary study that should be extended to other centers of scientific research.

Effect of image resolution manipulation in rearfoot angle measurements obtained with photogrammetry

The aim of this study was to investigate the influence of image resolution manipulation on the photogrammetric measurement of the rearfoot static angle. The study design was that of a reliability study. We evaluated 19 healthy young adults (11 females and 8 males). The photographs were taken at 1536 pixels in the greatest dimension, resized into four different resolutions (1200, 768, 600, 384 pixels) and analyzed by three equally trained examiners on a 96-pixels per inch (ppi) screen. An experienced physiotherapist marked the anatomic landmarks of rearfoot static angles on two occasions within a 1-week interval. Three different examiners had marked angles on digital pictures. The systematic error and the smallest detectable difference were calculated from the angle values between the image resolutions and times of evaluation. Different resolutions were compared by analysis of variance. Inter- and intra-examiner reliability was calculated by intra-class correlation coefficients (ICC). The rearfoot static angles obtained by the examiners in each resolution were not different (P > 0.05); however, the higher the image resolution the better the inter-examiner reliability. The intra-examiner reliability (within a 1-week interval) was considered to be unacceptable for all image resolutions (ICC range: 0.08-0.52). The whole body image of an adult with a minimum size of 768 pixels analyzed on a 96-ppi screen can provide very good inter-examiner reliability for photogrammetric measurements of rearfoot static angles (ICC range: 0.85-0.92), although the intra-examiner reliability within each resolution was not acceptable. Therefore, this method is not a proper tool for follow-up evaluations of patients within a therapeutic protocol.

Laboratory animal: biological reagent or living being?

The duties of humans toward non-human animals and their rights in society have been debated for a long time. However, a discussion on the terminology used for the identification of laboratory animals is usually not considered, although the employment of inadequate terminology may generate disastrous consequences for the animals before, during, and after the experiment. This study intends to defend the use of appropriate terminology, call attention to an unethical attitude of certain professionals when dealing with experimental animals, and also propose operational mechanisms, which allow for those distortions to be corrected.

Development of laboratory exercises for basic nuclear thermal hydraulics measurements

The thesis focuses on light water reactors (pressurized water reactors, boiling water reactors) and measurement techniques for basic thermal hydraulics parameters that are used in a nuclear power plant. The goal of this work is a development of laboratory exercises for basic nuclear thermal hydraulics measurements.

[1er mai 1920 à Paris, agent cycliste et cavaliers du service d'ordre à l'angle du boulevard Magenta et de la rue La Fayette] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 59109

1er mai 1920 à Paris, [des policiers molestent des manifestants devant le café Aux sources, à l'angle du boulevard de Magenta et de la rue Beaurepaire] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 59135

1er mai 1920 à Paris, [des policiers molestent des manifestants devant la taverne du Château d'Eau, à l'angle du boulevard de Magenta et de la rue Boulanger] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 59136