EFFECT OF POST-EMERGENCE HERBICIDE APPLICATIONS ON RICE CROP WEED COMMUNITIES IN TOLIMA, COLOMBIA

ABSTRACTThe weed communities of agricultural systems are dynamic and respond to changes in agronomic practices. This study aimed to evaluate the effect of post-emergence herbicide control programs made by farmers on weed communities and commercial lots of rice. The evaluations were carried out in 96 commercial lots located in the Centro, Meseta and Norte zones of the department of Tolima. In each lot, 1 ha was marked off, in which the evaluations were carried out by randomly throwing a 0.2 x 0.2 m sampling-square 5 times. Samples were taken before the first post-emergence application, after the first post-emergence application, after the second post-emergence application, and once the post-emergence applications were finished. The evaluated variables included density and cover of the weeds and the crops. The IVI of each species was calculated and the control program was analyzed in terms of decreases in the number of individuals for the 15 more encountered species. Before the applications, higher density values were found. The first and second post-emergence applications reduced the average density by 41% and 12%, respectively, throughout the department. Between the first and fourth evaluations, the density of the weeds and crops decreased throughout the department by 51.7% and 39%, respectively. The weed density variable proved to be the most influential in the populations after the herbicide programs were carried out.

Painted Into a Corner by Communities and Collections? Free Yourself with Metadata

Poster at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

A tale of two communities

Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

Temporal and spatial variations in the structure of macroalgal communities associated with mangrove trees of Ilha do Cardoso, São Paulo state, Brazil

Temporal and spatial variations in species composition and vertical distribution of macroalgal communities growing on mangrove trees were analyzed bimonthly in the Ilha do Cardoso State Park, São Paulo state (25°03'S and 47°55'W), Southeastern Brazil. The macroalgal communities from mangroves of Perequê and Sítio Grande rivers comprised 10 and 18 taxa respectively. Bostrychia radicans (Mont.) Mont. and B. calliptera (Mont.) Mont. were the predominant taxa, present almost throughout the year and in all the sites studied. The species composition of macroalgal communities from both mangroves presented temporal and spatial variations related to environmental factors. The highest number of taxa was observed during colder, drier months, coinciding with the highest means of high water neap and short periods of continuous emersion (April to August). Some mangrove algae such as B. calliptera, Rhizoclonium spp., Caloglossa spp., and Boodleopsis pusilla (Collins) W. Taylor, Joly et Bernatowicz showed a high degree of tolerance to desiccation, being able to tolerate continuous emersion up to six days. The spatial variations in species composition were related to light, as observed in Catenella caespitosa (Withering) L. Irvine, which occurred in well-lit sites. No pattern of vertical zonation was observed, since Rhizoclonium spp., B. radicans, and B. calliptera occur over the entire vertical range. Variations in the range of vertical distribution of macroalgae of Perequê mangrove were mainly related to the variations in the tidal levels (mean high water neap and/or mean high water spring) while those observed in Sítio Grande mangrove were related to salinity variations, except for B. calliptera and Caloglossa spp. related to tidal levels and high irradiance, respectively.

Similarity among periphyton algal communities in a lentic-lotic gradient of the upper Paraná river floodplain, Brazil

Floristic comparison of periphyton communities from three systems with different hydrodynamic regimes (lentic, semilotic, and lotic) was carried out during high and low water periods on the Upper Paraná River floodplain. For each period and system, glass slides were sampled every two days during 18-day periods, and Eichhornia azurea Kunth petioles were sampled three times. A total of 228 species was collected, representing 12 classes, mainly diatoms and desmids. The highest species-richness was found in communities from lentic system and during high water. Species richness in the lotic system was more stable over succession and hydrological periods. Algal taxonomic structure in river community was clearly separated from the other two systems, with 43% of similarity level. The hydrological period was next in importance, followed last by the substratum type, with communities associated at 65-78% similarity levels, depending on system and hydrological period. The type of system, but not the water levels,was the main factor that influenced community richness, followed by disturbances caused by flood pulses and the operation of reservoirs upstream. The periphyton on artificial and natural substrata presented high degree of similarity.

Patterns of spatial distribution in macroalgal communities from tropical lotic ecosystems

Three sampling sites were analysed in each of the following tropical regions: 1) northwestern São Paulo State, representing a disturbed region; 2) Bonito, Mato Grosso do Sul State, representing a hard water region; and 3) Ubatuba, northern costal region of São Paulo State, a well preserved tropical rainforest region. The hard water region had the highest mean values for macroalgal species richness (6.3) and diversity index (H' = 0.62). Northwest and rainforest regions had the highest percent cover values (22.5% and 17.0%, respectively). All sites in the northwest region had one or two dominant species (percent cover significantly higher than the remaining species), characterizing the niche pre-emption distribution pattern. The same pattern was found in two sites of the Atlantic rainforest. The hard water region had dominance of one species in two out of the three sites, but differently from the northwest region, niche overlap values were lower, evidencing a patch distribution. Competition for space was one of the main factors to explain spatial distribution. Overall, sites characterized by niche pre-emption had lower species richness, higher values for niche width and overlap, dominance index and percent cover of dominant species. In contrast, sites characterized by patch distribution had higher species richness and lower values for niche overlap and width, dominance index and percent cover.

Let Go and Remember. How Finnish Communities Experienced and Memorialized School Shootings

This study examines the aftermath of mass violence in local communities. Two rampage school shootings that occurred in Finland are analyzed and compared to examine the ways in which communities experience, make sense of, and recover from sudden acts of mass violence. The studied cases took place at Jokela High School, in southern Finland, and at a polytechnic university in Kauhajoki, in western Finland, in 2007 and 2008 respectively. Including the perpetrators, 20 people lost their lives in these shootings. These incidents are part of the global school shooting phenomenon with increasing numbers of incidents occurring in the last two decades, mostly in North America and Europe. The dynamic of solidarity and conflict is one of the main themes of this study. It builds upon previous research on mass violence and disasters which suggests that solidarity increases after a crisis, and that this increase is often followed by conflict in the affected communities. This dissertation also draws from theoretical discussions on remembering, narrating, and commemorating traumatic incidents, as well as the idea of a cultural trauma process in which the origins and consequences of traumas are negotiated alongside collective identities. Memorialization practices and narratives about what happened are vital parts of the social memory of crises and disasters, and their inclusive and exclusive characteristics are discussed in this study. The data include two types of qualitative interviews; focused interviews with 11 crisis workers, and focused, narrative interviews with 21 residents of Jokela and 22 residents of Kauhajoki. A quantitative mail survey of the Jokela population (N=330) provided data used in one of the research articles. The results indicate that both communities experienced a process of simultaneous solidarity and conflict after the shootings. In Jokela, the community was constructed as a victim, and public expressions of solidarity and memorialization were promoted as part of the recovery process. In Kauhajoki, the community was portrayed as an incidental site of mass violence, and public expressions of solidarity by distant witnesses were labeled as unnecessary and often criticized. However, after the shooting, the community was somewhat united in its desire to avoid victimization and a prolonged liminal period. This can be understood as a more modest and invisible process of “silent solidarity”. The processes of enforced solidarity were partly made possible by exclusion. In some accounts, the family of the perpetrator in Jokela was excluded from the community. In Kauhajoki, the whole incident was externalized. In both communities, this exclusion included associating the shooting events, certain places, and certain individuals with the concept of evil, which helped to understand and explain the inconceivable incidents. Differences concerning appropriate emotional orientations, memorialization practices and the pace of the recovery created conflict in both communities. In Jokela, attitudes towards the perpetrator and his family were also a source of friction. Traditional gender roles regarding the expression of emotions remained fairly stable after the school shootings, but in an exceptional situation, conflicting interpretations arose concerning how men and women should express emotion. The results from the Jokela community also suggest that while increased solidarity was seen as important part of the recovery process, some negative effects such as collective guilt, group divisions, and stigmatization also emerged. Based on the results, two simultaneous strategies that took place after mass violence were identified; one was a process of fast-paced normalization, and the other was that of memorialization. Both strategies are ways to restore the feeling of security shattered by violent incidents. The Jokela community emphasized remembering while the Kauhajoki community turned more to the normalization strategy. Both strategies have positive and negative consequences. It is important to note that the tendency to memorialize is not the only way of expressing solidarity, as fast normalization includes its own kind of solidarity and helps prevent the negative consequences of intense solidarity.

From genes to communities : stress tolerance in eelgrass (Zostera marina)

Shallow coastal areas are dynamic habitats that are affected by a variety of abiotic and biotic factors. In addition to the natural environmental stress, estuarine and coastal seagrass ecosystems are exposed to effects of climate change and other anthropogenic impacts. In this thesis the effect of different abiotic (shading stress, salinity and temperature) and biotic stressors (presence of co-occurring species) and different levels and combinations of stressors on the performance and survival of eelgrass (Zostera marina) was assessed. To investigate the importance of scale for stress responses, varying levels of biological organization (genotype, life stage, population and plant community) were studied in field and aquarium experiments. Light limitation, decreased salinity and increased temperature affected eelgrass performance negatively in papers I, II and III, respectively. While co-occurring plant species had no notable effect on eelgrass in paper IV, the presence of eelgrass increased the biomass of Potamogeton perfoliatus. The findings in papers II and III confirmed that more extreme levels of salinity and temperature had stronger impacts on plant performance compared to intermediate levels, but intermediate levels also had more severe effects on plants when they were exposed to several stressors, as illustrated in paper II. Thus, multiple stressors had negative synergetic effects. The results in papers I, II and III indicate that future changes in light climate, salinity and temperature can have serious impacts on eelgrass performance and survival. Stress responses were found to vary among genotypes, life stages and populations in papers I, II and III, respectively, emphasizing the importance of study scale. The results demonstrate that while stress in general affects seagrass productivity negatively, the severity of effects can vary substantially depending on the studied scale or level of biological organization. Eelgrass genotypes can differ in their stress and recovery processes, as observed in paper I. In paper II, eelgrass seedlings were less prone to abiotic stress compared to adult plants, but stress also decreased their survival considerably. This indicates that recruitment and re-colonization through seeds might be threatened in the future. Variation among population responses observed in paper III indicates that long-term local adaptation under differing selection pressures has caused divergence in salinity tolerance between Baltic eelgrass populations. This variability in stress tolerance observed in papers I and III suggests that some eelgrass genotypes and populations have a better capacity to adapt to changes and survive in a changing environment. Multiple stressors and biological level-specific responses demonstrate the uncertainty in predicting eelgrass responses in a changing environment. As eelgrass populations may differ in their stress tolerance both within and across regions, conservation strategies at both local and regional scales are urgently needed in order to ensure the survival of these important ecosystems.

Comparative study of human exposure to mercury in riverside communities in the Amazon region

Four populations in the Amazon area were selected for a comparative study of mercury-exposed and non-exposed populations: São Luiz do Tapajós, Barreiras, Panacauera, and Pindobal Grande. The highest mercury levels in human hair samples were found in São Luiz do Tapajós and Barreiras, greatly exceeding the limits established by the World Health Organization. Panacauera showed an intermediate level below 9 µg/g. This was the first comparative and simultaneous evaluation of mercury exposure in the Amazon area. Also, thanks to this type of monitoring, we were able to eliminate the uncertainties about the reference dose. On the basis of these data, we can conclude that the mercury levels detected in exposed populations of the Tapajós River basin may be dangerous not only because they are above the World Health Organization limits, but also because the simultaneous mercury detection in non-exposed populations with similar characteristics provided a valid control and revealed lower mercury levels. Our results support the importance of continuous monitoring in both exposed and non-exposed populations.

Glutamic acid decarboxylase antibodies are indicators of the course, but not of the onset, of diabetes in middle-aged adults: the Atherosclerosis Risk in Communities Study

To efficiently examine the association of glutamic acid decarboxylase antibody (GADA) positivity with the onset and progression of diabetes in middle-aged adults, we performed a case-cohort study representing the ~9-year experience of 10,275 Atherosclerosis Risk in Communities Study participants, initially aged 45-64 years. Antibodies to glutamic acid decarboxylase (GAD65) were measured by radioimmunoassay in 580 incident diabetes cases and 544 non-cases. The overall weighted prevalence of GADA positivity (³1 U/mL) was 7.3%. Baseline risk factors, with the exception of smoking and interleukin-6 (P £ 0.02), were generally similar between GADA-positive and -negative individuals. GADA positivity did not predict incident diabetes in multiply adjusted (HR = 1.04; 95%CI = 0.55, 1.96) proportional hazard analyses. However, a small non-significant adjusted risk (HR = 1.29; 95%CI = 0.58, 2.88) was seen for those in the highest tertile (³2.38 U/mL) of positivity. GADA-positive and GADA-negative non-diabetic individuals had similar risk profiles for diabetes, with central obesity and elevated inflammation markers, aside from glucose, being the main predictors. Among diabetes cases at study's end, progression to insulin treatment increased monotonically as a function of baseline GADA level. Overall, being GADA positive increased risk of progression to insulin use almost 10 times (HR = 9.9; 95%CI = 3.4, 28.5). In conclusion, in initially non-diabetic middle-aged adults, GADA positivity did not increase diabetes risk, and the overall baseline profile of risk factors was similar for positive and negative individuals. Among middle-aged adults, with the possible exception of those with the highest GADA levels, autoimmune pathophysiology reflected by GADA may become clinically relevant only after diabetes onset.

Indoor NO2 air pollution and lung function of professional cooks

Studies of cooking-generated NO2 effects are rare in occupational epidemiology. In the present study, we evaluated the lung function of professional cooks exposed to NO2 in hospital kitchens. We performed spirometry in 37 cooks working in four hospital kitchens and estimated the predicted FVC, FEV1 and FEF25-75, based on age, sex, race, weight, and height, according to Knudson standards. NO2 measurements were obtained for 4 consecutive days during 4 different periods at 20-day intervals in each kitchen. Measurements were performed inside and outside the kitchens, simultaneously using Palm diffusion tubes. A time/exposure indicator was defined as representative of the cumulative exposure of each cook. No statistically significant effect of NO2 exposure on FVC was found. Each year of work as a cook corresponded to a decrease in predicted FEV1 of 2.5% (P = 0.046) for the group as a whole. When smoking status and asthma were included in the analysis the effect of time/exposure decreased about 10% and lost statistical significance. On predicted FEF25-75, a decrease of 3.5% (P = 0.035) was observed for the same group and the inclusion of controllers for smoking status and asthma did not affect the effects of time/exposure on pulmonary function parameter. After a 10-year period of work as cooks the participants of the study may present decreases in both predicted FEV1 and FEF25-75 that can reach 20 and 30%, respectively. The present study showed small but statistically significant adverse effects of gas stove exposure on the lung function of professional cooks.

Stability of relative oxygen pulse curve during repeated maximal cardiopulmonary testing in professional soccer players

During cardiopulmonary exercise testing (CPET), stroke volume can be indirectly assessed by O2 pulse profile. However, for a valid interpretation, the stability of this variable over time should be known. The objective was to analyze the stability of the O2 pulse curve relative to body mass in elite athletes. VO2, heart rate (HR), and relative O2 pulse were compared at every 10% of the running time in two maximal CPETs, from 2005 to 2010, of 49 soccer players. Maximal values of VO2 (63.4 ± 0.9 vs 63.5 ± 0.9 mL O2•kg-1•min-1), HR (190 ± 1 vs188 ± 1 bpm) and relative O2 pulse (32.9 ± 0.6 vs 32.6 ± 0.6 mL O2•beat-1•kg-1) were similar for the two CPETs (P > 0.05), while the final treadmill velocity increased from 18.5 ± 0.9 to 18.9 ± 1.0 km/h (P < 0.01). Relative O2 pulse increased linearly and similarly in both evaluations (r² = 0.64 and 0.63) up to 90% of the running time. Between 90 and 100% of the running time, the values were less stable, with up to 50% of the players showing a tendency to a plateau in the relative O2 pulse. In young healthy men in good to excellent aerobic condition, the morphology of the relative O2 pulse curve is consistent up to close to the peak effort for a CPET repeated within a 1-year period. No increase in relative O2pulse at peak effort could represent a physiologic stroke volume limitation in these athletes.

Translating with the Web. Professional translators' information-seeking behaviour in translation with online resources

Tämän tutkielman aiheena on ammattikääntäjien tiedonhaku, kun käytettävissä on ainoastaan verkkolähteitä. Tutkimuksessa on tarkasteltu, mistä ja miten ammattikääntäjät etsivät tietoa internetistä kääntäessään lähtötekstiä englannista suomeen. Lisäksi tutkimuksen tarkoituksena on osoittaa, että tiedonhakutaidot ja lähdekriittisyys ovat käännöskompetensseja, joita tulisi sekä ylläpitää että opettaa osana kääntäjäkoulutusta. Tutkimuksen aineisto kerättiin empiirisesti käyttämällä kolmea metodia. Käännösprosessi ja sen aikana tapahtunut tiedonhaku tallennettiin käyttäen Camtasia-näyttövideointiohjelmaa ja Translog-II -näppäilyntallennusohjelmaa. Lisäksi tutkimukseen osallistuneet kääntäjät täyttivät kaksi kyselyä, joista ensimmäinen sisälsi taustatietokysymyksiä ja toinen itse prosessiin liittyviä retrospektiivisiä kysymyksiä. Kyselyt toteutettiin Webropol-kyselytyökalulla. Aineistoa kerättiin yhteensä viidestä koetilanteesta. Tutkimuksessa tarkasteltiin lähemmin kolmen ammattikääntäjän tiedon-hakutoimintoja erottelemalla käännösprosesseista ne tauot, joiden aikana kääntäjät etsivät tietoa internetistä. Käytettyjen verkkolähteiden osalta tutkimuksessa saatiin vastaavia tuloksia kuin aiemmissakin tutkimuksissa: eniten käytettyjä olivat Google, Wikipedia sekä erilaiset verkkosanakirjat. Tässä tutkimuksessa kuitenkin paljastui, että ammattikääntäjien tiedonhaun toimintamallit vaihtelevat riippuen niin kääntäjän erikoisalasta kuin hänen tiedonhakutaitojensa tasosta. Joutuessaan työskentelemään tutun työympäristönsä ja oman erikoisalansa ulkopuolella turvautuu myös osa ammattikääntäjistä alkeellisimpiin tiedonhakutekniikoihin, joita käännöstieteen opiskelijoiden on havaittu yleisesti käyttävän. Tulokset paljastivat myös, että tiedonhaku voi viedä jopa 70 prosenttia koko käännösprosessiin kuluvasta ajasta riippuen kääntäjän aiemmasta lähtötekstin aihepiiriin liittyvästä tietopohjasta ja tiedonhaun tehokkuudesta. Tutkimuksessa saatujen tulosten pohjalta voidaan sanoa, että myös ammattikääntäjien tulisi kehittää tiedonhakutaitojaan pitääkseen käännösprosessinsa tehokkaana. Lisäksi kääntäjien pitäisi muistaa arvioida kriittisesti käyttämiään tietolähteitä: lähdekritiikki on tarpeen erityisesti verkkolähteitä käytettäessä. Tästä syystä tiedonhakutaitoja ja lähdekriittisyyttä tulisikin opettaa ja harjoitella jo osana kääntäjäkoulutusta. Kääntäjien ei myöskään pidä jättää tiedonhakua pelkkien verkkolähteiden varaan, vaan jatkossakin käyttää hyväkseen niin painettuja tietolähteitä kuin myös henkilölähteitä.