1000 resultados para 67-500


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We present entire sequences of two hymenopteran mitochondrial genomes and the major portion of three others. We combined these data with nine previously sequenced hymenopteran mitochondrial genomes. This allowed us to infer and analyze the evolution of the 67 mitochondrial gene rearrangements so far found in this order. All of these involve tRNA genes, whereas four also involve larger (protein-coding or ribosomal RNA) genes. We find that the vast majority of mitochondrial gene rearrangements are independently derived. A maximum of four of these rearrangements represent shared, derived organizations, whereas three are convergently derived. The remaining mitochondrial gene rearrangements represent new mitochondrial genome organizations. These data are consistent with the proposal that there are an enormous number of alternative mitochondrial genome organizations possible and that mitochondrial genome organization is, for the most part, selectively neutral. Nevertheless, some mitochondrial genes appear less mobile than others. Genes close to the noncoding region are generally more mobile but only marginally so. Some mitochondrial genes rearrange in a pattern consistent with the duplication/random loss model, but more mitochondrial genes move in a pattern inconsistent with this model. An increased rate of mitochondrial gene rearrangement is not tightly associated with the evolution of parasitism. Although parasitic lineages tend to have more mitochondrial gene rearrangements than nonparasitic lineages, there are exceptions (e.g., Orussus and Schlettererius). It is likely that only a small proportion of the total number of mitochondrial gene rearrangements that have occurred during the evolution of the Hymenoptera have been sampled in the present study.

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The mining industry is highly suitable for the application of robotics and automation technology since the work is arduous, dangerous and often repetitive. This paper discusses a robust sensing system developed to find and trade the position of the hoist ropes of a dragline. Draglines are large `walking cranes' used in open-pit coal mining to remove the material covering the coal seam. The rope sensing system developed uses two time-of-flight laser scanners. The finding algorithm uses a novel data association and tracking strategy based on pairing rope data.

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The mining industry is highly suitable for the application of robotics and automation technology since the work is arduous, dangerous and often repetitive. This paper describes the development of an automation system for a physically large and complex field robotic system - a 3,500 tonne mining machine (a dragline). The major components of the system are discussed with a particular emphasis on the machine/operator interface. A very important aspect of this system is that it must work cooperatively with a human operator, seamlessly passing the control back and forth in order to achieve the main aim - increased productivity.

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The surfaces of natural beidellite clay were modified with cationic surfactant, tetradecyltrimethylammonium bromide, at different concentrations. The organo-beidellites were analysed using thermogravimetric analysis which shows four thermal oxidation/decomposition steps. The first step of mass loss is observed from room temperature to 130 °C due to the dehydration of adsorbed water. The second step of mass loss between 130 and 400 °C is attributed to the oxidation step of the intercalated organic surfactant with the formation of charcoal. The third mass loss happens between 400 and 500 °C which is assigned to the loss of hydroxyl groups on the edge of clays and the further oxidation step of charcoal. The fourth step is ascribed to the loss of structural OH units as well as the final oxidation/decomposition step of charcoal which takes place between 500 and 700 °C. Thermogravimetric analysis has proven to be a useful tool for estimating loaded surfactant amount.

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BACKGROUND Quantification of the disease burden caused by different risks informs prevention by providing an account of health loss different to that provided by a disease-by-disease analysis. No complete revision of global disease burden caused by risk factors has been done since a comparative risk assessment in 2000, and no previous analysis has assessed changes in burden attributable to risk factors over time. METHODS We estimated deaths and disability-adjusted life years (DALYs; sum of years lived with disability [YLD] and years of life lost [YLL]) attributable to the independent effects of 67 risk factors and clusters of risk factors for 21 regions in 1990 and 2010. We estimated exposure distributions for each year, region, sex, and age group, and relative risks per unit of exposure by systematically reviewing and synthesising published and unpublished data. We used these estimates, together with estimates of cause-specific deaths and DALYs from the Global Burden of Disease Study 2010, to calculate the burden attributable to each risk factor exposure compared with the theoretical-minimum-risk exposure. We incorporated uncertainty in disease burden, relative risks, and exposures into our estimates of attributable burden. FINDINGS In 2010, the three leading risk factors for global disease burden were high blood pressure (7·0% [95% uncertainty interval 6·2-7·7] of global DALYs), tobacco smoking including second-hand smoke (6·3% [5·5-7·0]), and alcohol use (5·5% [5·0-5·9]). In 1990, the leading risks were childhood underweight (7·9% [6·8-9·4]), household air pollution from solid fuels (HAP; 7·0% [5·6-8·3]), and tobacco smoking including second-hand smoke (6·1% [5·4-6·8]). Dietary risk factors and physical inactivity collectively accounted for 10·0% (95% UI 9·2-10·8) of global DALYs in 2010, with the most prominent dietary risks being diets low in fruits and those high in sodium. Several risks that primarily affect childhood communicable diseases, including unimproved water and sanitation and childhood micronutrient deficiencies, fell in rank between 1990 and 2010, with unimproved water and sanitation accounting for 0·9% (0·4-1·6) of global DALYs in 2010. However, in most of sub-Saharan Africa childhood underweight, HAP, and non-exclusive and discontinued breastfeeding were the leading risks in 2010, while HAP was the leading risk in south Asia. The leading risk factor in Eastern Europe, most of Latin America, and southern sub-Saharan Africa in 2010 was alcohol use; in most of Asia, North Africa and Middle East, and central Europe it was high blood pressure. Despite declines, tobacco smoking including second-hand smoke remained the leading risk in high-income north America and western Europe. High body-mass index has increased globally and it is the leading risk in Australasia and southern Latin America, and also ranks high in other high-income regions, North Africa and Middle East, and Oceania. INTERPRETATION Worldwide, the contribution of different risk factors to disease burden has changed substantially, with a shift away from risks for communicable diseases in children towards those for non-communicable diseases in adults. These changes are related to the ageing population, decreased mortality among children younger than 5 years, changes in cause-of-death composition, and changes in risk factor exposures. New evidence has led to changes in the magnitude of key risks including unimproved water and sanitation, vitamin A and zinc deficiencies, and ambient particulate matter pollution. The extent to which the epidemiological shift has occurred and what the leading risks currently are varies greatly across regions. In much of sub-Saharan Africa, the leading risks are still those associated with poverty and those that affect children.

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We have genotyped 14,436 nonsynonymous SNPs (nsSNPs) and 897 major histocompatibility complex (MHC) tag SNPs from 1,000 independent cases of ankylosing spondylitis (AS), autoimmune thyroid disease (AITD), multiple sclerosis (MS) and breast cancer (BC). Comparing these data against a common control dataset derived from 1,500 randomly selected healthy British individuals, we report initial association and independent replication in a North American sample of two new loci related to ankylosing spondylitis, ARTS1 and IL23R, and confirmation of the previously reported association of AITD with TSHR and FCRL3. These findings, enabled in part by increased statistical power resulting from the expansion of the control reference group to include individuals from the other disease groups, highlight notable new possibilities for autoimmune regulation and suggest that IL23R may be a common susceptibility factor for the major 'seronegative' diseases.

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Tutkimuksen tarkoituksena on analysoida eräitä lakitermejä, jotka esiintyvät papyruksessa P. Petra inv. 83. Kyseinen dokumentti, joka sisältää sopimuksen kahden naapuruksen välisen kiistan lopettamiseksi, ajoittuu todennäköisesti vuodelle 574 jKr. ja se kuuluu Jordanian Petrasta vuonna 1993 löydettyyn hiiltyneeseen papyrusarkistoon. Papyrus on tällä hetkellä vielä julkaisematon, ja tämä työ on osa siihen liittyvää perustutkimusta, jonka tarkoituksena on toisaalta selittää tekstin itsensä sisältö, toisaalta arvioida sen antaman informaation merkitystä laajemmassa historiallisessa kontekstissa. Papyrus on kirjoitettu kreikaksi, Bysantin eli Itä-Rooman valtakunnan virallisella kielellä, mutta itse lakitermeistä suurin osa liittyy alun perin latinan kielellä luotuun roomalaiseen oikeuteen. Paikallinen väestö puolestaan oli seemiläistä alkuperää, jolla ei ainoastaan ollut oma kieli, vaan jolla oli ollut ennen valtakuntaan liittämistä omat oikeustraditionsakin. Niinpä papyruksessa esiintyvien termien tutkimuksen kautta nousevat esille monenlaiset laajemmatkin kysymyksenasettelut. Lakitermejä analysoidaan pääasiassa kolmesta näkökulmasta. Ensisijaisena pyrkimyksenä on selvittää niiden tarkka merkitys asiayhteydessään, joka papyruksen fragmentaarisuuden vuoksi ei ole etukäteen selvä, ja siten edistää tekstissä puheena olevien asianhaarojen ymmärtämistä. Toiseksi termien käyttöä koskevat tulokset suhteutetaan yleiseen oikeushistoriaan ja pyritään arvioimaan niiden merkitystä Petrassa käytössä olleen oikeusjärjestelmän kannalta. Kolmas näkökulma on kielitieteellinen, sillä termien käyttö papyruksessa on nähtävä osana laajempaa kehitystä, jossa roomalaisen oikeuden vähittäinen muuttuminen bysanttilaiseksi johti kielten vaihtumiseen ja koko juridisen käsitteistön siirtymiseen latinasta kreikkaan. Siksi tässä työssä käytetään itse papyruksen analyysin lisäksi laajaa vertailumateriaalia, joka koostuu ennen kaikkea roomalaisesta ja bysanttilaisesta lakikirjallisuudesta sekä dokumentaarisesta lähdeaineistosta, etenkin egyptiläisistä papyruksista. Niin tässä papyruksessa kuin muissakin kreikankielisissä lähteissä esiintyvät roomalaiseen oikeuteen liittyvät termit voidaan jaotella suoriin lainoihin, käännöslainoihin sekä komparaatiolainoihin. Jälkimmäisillä tarkoitetaan kreikan kielessä jo aiemmin käytössä olleita termejä, jotka eivät sananmukaiselta merkitykseltään vastaa latinalaisia, mutta joita alettiin käyttää jonkin latinalaisen termin vastineina. Tutkimus tekee selväksi, että olipa kyse mistä lainakategoriasta tahansa, lakitermien siirtyessä kielestä toiseen tapahtui yleensä semanttisia muutoksia eikä termejä aina käytetty samalla tavalla kuin alkukielessä. Merkityskenttä saattoi esimerkiksi supistua taikka laajentua tai sanalle saattoi kehittyä lainautumisen jälkeen täysin uusiakin merkityksiä. Oikeushistorian suhteen on huomioitava ero virallisten säännösten ja provinsseissa noudatettujen käytäntöjen välillä. Kaiken kaikkaan Petra näyttää kuitenkin olleen kiinteä osa Bysantin valtakuntaa, jonka lakeja ainakin pääpiirteissään noudatettiin. Kaikkien termien käytötavat eivät tosin ole johdettavissa suoraan virallisiin lakikorpuksiin, mutta ne eivät myöskään sodi niitä vastaan. Roomalaisen oikeuden tuntemus näyttää olleen Petrassa jopa parempaa kuin esimerkiksi Egyptissä. Mitä tulee papyruksessa puheena oleviin konkreettisiin asianhaaroihin, termien merkityksen ymmärtäminen selventää joidenkin aspektien pääpiirteitä, kun taas yksityskohdat jäävät tekstin fragmentaarisuuden takia useimmiten epäselviksi. Avainsanat: papyrologia, Petra, roomalainen oikeus, terminologia, kreikan kieli, latinan kieli, lainasanat

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Participants include Erna Hirsch, Else Giesenow, Marta Nachmann, Erna Goldschmidt (Goldi), Lotte Strauss, Marta Bruchfeld, Toni Eichenberg, Grete Guthmann, Flora Goldschmidt, Hedwig Trum, Hedel Korhmann, Paula Arendt, Erna Behr and Frl. Minka Friedmann

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The influence of chemical mutation featuring the selective conversion of asparagine or glutamine to aspartic or glutamic acid, respectively, on the kinetics of refolding of reduced RNase has been studied. The monodeamidated derivatives of RNase A, viz. RNase Aa1a, Aa1b, and Aa1c having their deamidations in the region 67-74, were found to regain nearly their original enzymatic activity. However, a marked difference in the kinetics of refolding is seen, the order of regain of enzymic activity being RNase A greater than Aa1c congruent to Aa1a greater than Aa1b. The similarities in the distinct elution positions on Amberlite XE-64, gel electrophoretic mobilities, and u.v. spectra of reoxidized and native derivatives indicated that the native structures are formed. The slower rate of reappearance of enzymic activity in the case of the monodeamidated derivatives appears to result from altered interactions in the early stages of refolding. The roles of some amino acid residues of the 67-74 region in the pathway of refolding of RNase A are discussed.

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Recent advancements in the area of organic polymer applications demand novel and advanced materials with desirable surface, optical and electrical properties to employ in emerging technologies. This study examines the fabrication and characterization of polymer thin films from non-synthetic Terpinen-4-ol monomer using radio frequency plasma polymerization. The optical properties, thickness and roughness of the thin films were studied in the wavelength range 200–1000 nm using ellipsometry. The polymer thin films of thickness from 100 nm to 1000 nm were fabricated and the films exhibited smooth and defect-free surfaces. At 500 nm wavelength, the refractive index and extinction coefficient were found to be 1.55 and 0.0007 respectively. The energy gap was estimated to be 2.67 eV, the value falling into the semiconducting Eg region. The obtained optical and surface properties of Terpinen-4-ol based films substantiate their candidacy as a promising low-cost material with potential applications in electronics, optics, and biomedical industries.

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This study compared pregnancy rates (PRs) and costs per calf born after fixed-time artificial insemination (FTAI) or AI after estrus detection (i.e., estrus detection and AI, EDAI), before and after a single PGF2α treatment in Bos indicus (Brahman-cross) heifers. On Day 0, the body weight, body condition score, and presence of a CL (46% of heifers) were determined. The heifers were then alternately allocated to one of two FTAI groups (FTAI-1, n = 139) and (FTAI-2, n = 141) and an EDAI group (n = 273). Heifers in the FTAI groups received an intravaginal progesterone-releasing device (IPRD; 0.78 g of progesterone) and 1 mg of estradiol benzoate intramuscularly (im) on Day 0. Eight days later, the IPRD was removed and heifers received 500 μg of PGF2α and 300 IU of eCG im; 24 hours later, they received 1 mg estradiol benzoate im and were submitted to FTAI 30 to 34 hours later (54 and 58 hours after IPRD removal). Heifers in the FTAI-2 group started treatment 8 days after those in the FTAI-1 group. Heifers in the EDAI group were inseminated approximately 12 hours after the detection of estrus between Days 4 and 9 at which time the heifers that had not been detected in estrus received 500 μg of PGF2α im and EDAI continued until Day 13. Heifers in the FTAI groups had a higher overall PR (proportion pregnant as per the entire group) than the EDAI group (34.6% vs. 23.2%; P = 0.003), however, conception rate (PR of heifers submitted for AI) tended to favor the estrus detection group (34.6% vs. 44.1%; P = 0.059). The cost per AI calf born was estimated to be $267.67 and $291.37 for the FTAI and EDAI groups, respectively. It was concluded that in Brahman heifers typical of those annually mated in northern Australia FTAI compared with EDAI increases the number of heifers pregnant and reduces the cost per calf born.

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Composite of anatase titania (TiO2) nanospheres and carbon grown and self-assembled into micron-sized mesoporous spheres via a solvothermal synthesis route are discussed here in the context of rechargeable lithium-ion battery. The morphology and carbon content and hence the electrochemical performance are observed to be significantly influenced by the synthesis parameters. Synthesis conditions resulting in a mesoporous arrangement of an optimized amount carbon and TiO2 exhibited the best lithium battery performance. The first discharge cycle capacity of carbon-titania mesoporous spheres (solvothermal reaction at 150 degrees C at 6 h, calcination at 500 degrees C under air, BET surface area 80 m(2)g(-1)) was 334 mAhg(-1) (approximately 1 Li) at current rate of 0.066 Ag-1. High storage capacity and good cyclability is attributed to the nanostructuring of TiO2 (mesoporosity) as well as due to formation of a percolation network of carbon around the TiO2 nanoparticles. The micron-sized mesoporous spheres of carbon-titania composite nanoparticles also show good rate cyclability in the range (0.066-6.67) Ag-1.

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Background: Helicobacter pylori infection is usually acquired in early childhood and is rarely resolved spontaneously. Eradication therapy is currently recommended virtually to all patients. While the first and second therapies are prescribed without knowing the antibiotic resistance of the bacteria, it is important to know the primary resistance in the population. Aim: This study evaluates the primary resistance of H. pylori among patients in primary health care throughout Finland, the efficacy of three eradication regimens, the symptomatic response to successful therapy, and the effect of smoking on gastric histology and humoral response in H. pylori-positive patients. Patients and methods: A total of 23 endoscopy referral centres located throughout Finland recruited 342 adult patients with positive rapid urease test results, who were referred to upper gastrointestinal endoscopy from primary health care. Gastric histology, H. pylori resistance and H. pylori serology were evaluated. The patients were randomized to receive a seven-day regimen, comprising 1) lansoprazole 30 mg b.d., amoxicillin 1 g b.d. and metronidazole 400 mg t.d. (LAM), 2) lansoprazole 30 mg b.d., amoxicillin 1 g b.d. and clarithromycin 500 mg b.d. (LAC) or 3) ranitidine bismuth citrate 400 mg b.d., metronidazole 400 mg t.d. and tetracycline 500 mg q.d. (RMT). The eradication results were assessed, using the 13C-urea breath test 4 weeks after therapy. The patients completed a symptom questionnaire before and a year after the therapy. Results: Primary resistance of H. pylori to metronidazole was 48% among women and 25% among men. In women, metronidazole resistance correlated with previous use of antibiotics for gynaecologic infections and alcohol consumption. Resistance rate to clarithromycin was only 2%. Intention-to-treat cure rates of LAM, LAC, and RMT were 78%, 91% and 81%. While in metronidazole-sensitive cases the cure rates with LAM, LAC and RMT were similar, in metronidazole resistance LAM and RMT were inferior to LAC (53%, 67% and 84%). Previous antibiotic therapies reduced the efficacy of LAC, to the level of RMT. Dyspeptic symptoms in the Gastrointestinal Symptoms Rating Scale (GSRS) were decreased by 30.5%. In logistic regression analysis, duodenal ulcer, gastric antral neutrophilic inflammation and age from 50 to 59 years independently predicted greater decrease in dyspeptic symptoms. In the gastric body, smokers had milder inflammation and less atrophy and in the antrum denser H. pylori load. Smokers also had lower IgG antibody titres against H. pylori and a smaller proportional decrease in antibodies after successful eradication. Smoking tripled the risk of duodenal ulcers. Conclusions: in Finland H. pylori resistance to clarithromycin is low, but metronidazole resistance among women is high making metronidazole-based therapies unfavourable. Thus, LAC is the best choice for first-line eradication therapy. The effect of eradication on dyspeptic symptoms was only modest. Smoking slows the progression of atrophy in the gastric body.

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Tutkimukseni kohteena ovat mies- ja naispuoliset tutkijat ja tohtoriopiskelijat, jotka ovat osallistuneet katalyysitutkimukseen keskittyvän tutkimusverkosto IDECAT:in toimintaan. Tutkielmassani pyrin selvittämään, onko naisten ja miesten tutkijanuran välillä eroa ja jos on, niin minkälainen tämä ero on. Pyrin myös saamaan selville, onko naisten tutkijanuralla esteitä ja esiintyykö tiedeyhteisössä sukupuolesta johtuvaa syrjintää. IDECAT (Integrated Design of Catalytic Nanomaterials for a Sustainable Production) on EU-rahoitteinen, kemian tekniikkaan liittyvään katalyysitutkimukseen keskittyvä tutkimusverkosto, johon kuuluu alan tutkimusyksiköitä ja yliopistoja 12 Euroopan maasta. IDECAT:iin kuuluu noin 500-600 henkilöä. Tutkimukseni pohjautuu kahteen kyselytutkimukseen, jotka toteutettiin Internetissä 2009-2010. Ensimmäinen kyselytutkimus oli vastaajien saatavilla loka-marraskuussa 2009 ja siinä selvitettiin IDECAT:in tutkijoiden ja tohtoriopiskelijoiden tasa-arvotilannetta yleisesti. Kyselyyn vastasi 83 henkilöä, joista 51% oli naisia ja 49 % miehiä. Kyselyssä käytettiin strukturoitua kyselylomaketta ja tulokset analysoitiin kvantitatiivisesti SPSS tilasto-ohjelmalla. Tilastollisena menetelmänä käytän ristiintaulukointia. Toinen kyselytutkimus (jatkokysely) keskittyy tiedeyhteisössä tapahtuvaan sukupuolesta johtuvaan syrjintään ja se oli vastaajien saatavilla huhti-toukokuussa 2010. Jatkokyselyn kysymykset ovat avokysymyksiä ja ne analysoitiin laadullisesti. Jatkokyselyyn vastasi 24 henkilöä, joista 6 kuvasi yksityiskohtaisesti syrjintäkokemuksiaan tiedeyhteisössä. Teoreettisena viitekehyksenä käytän tutkimuksessani Joan Ackerin sukupuolittuneen organisaation teoriaa ja siihen liittyviä, organisaation toiminnassa ilmeneviä sukupuolittuneita prosesseja. Sukupuolittuneet prosessit ovat ajattelutapoja , käytäntöjä ja asenteita, joilla sukupuolet erotetaan toisistaan ja joilla tuotetaan sukupuolten välisiä valtasuhteita. Naisten ja miesten tutkijanuran välillä on aineistossani joitakin merkittäviä eroja. Sukupuolesta johtuva syrjintä on yleistä vastaajien keskuudessa ja naiset ovat kokeneet sitä useammin kuin miehet. 67% naisvastaajista ja 37% miesvastaajista on kokenut sukupuolesta johtuvaa syrjintää. Naisvastaajat myös kokevat miehiä useammin, että he eivät saa riittävästi tukea ja kannustusta esimiehiltään. Lisäksi naisia on pyydetty mukaan tieteelliseen yhteistyöhön miehiä harvemmin. Useimmat muuttujat eivät kuitenkaan tuo eroa sukupuolten välille. Tutkijanaiset kokevat ylenemismahdollisuutensa lähes yhtä hyviksi kuin miehet, naiset ja miehet työskentelevät yhtä usein määräaikaisissa tehtävissä ja naiset työskentelevät kokopäiväisesti lähes yhtä usein kuin miehet. Naiset pitävät perheen ja työn yhdistämistä helppona. Sukupuolittuneita prosesseja ilmenee erityisesti sukupuolten väliseen työnjakoon ja sosiaalisen tuen ja vallan jakoon tiedeyhteisössä liittyvissä tilanteissa. Sukupuolittuneisuus ei kuitenkaan ole totaalista, monien kyselyn muuttujien kohdalla sukupuolittumista tai eroa sukupuolten välille ei tullut. Monet kyselyn muuttujat osoittavatkin, että naiset ja miehet kokevat, että heitä kohdellaan melko tasa-arvoisesti. Tietyillä osa-alueilla epätasa-arvoisen kohtelun kokemukset ovat kuitenkin yleisiä, mikä tuottaa ristiriitaisen kuvan tiedeyhteisön tasa-arvotilanteesta. Tämä voi viitata siihen, että tutkijanaisten ja miesten asemat ja roolit tiedeyhteisössä eivät ole pysyviä ja staattisia, vaan aktiivisessa muutoksen tilassa. Tutkijanaisten asemaa tiedeyhteisössä voidaan lisäksi parantaa reagoimalla ja puuttumalla sukupuolesta johtuvaan syrjintään, pitämällä tasa-arvoasioita esillä sekä kiinnittämällä huomiota johtamiskäytäntöihin, esimerkiksi palkkaamalla lisää naisjohtajia. Avainsanat Keywords: Sukupuolittunut organisaatio, sukupuolittuneet prosessit, kyselytutkimus, kvantitatiivinen tutkimus, tiedeyhteisö, sukupuolisyrjintä, tutkijanaiset, naistutkijat, sukupuolten tasa-arvo, gendered organization, academia, female scientists, gender equality

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Groundwater is a significant water resource in India for domestic, irrigation, and industrial needs. By far the most serious natural groundwater-quality problem in India, in terms of public health, derives from high fluoride, arsenic, and iron concentrations. Hydrogeochemical investigation of fluoride contaminated groundwater samples from Kolar and Tumkur Districts in Karnataka are undertaken to understand the quality and potability of groundwater from the study area, the level of fluoride contamination, the origin and geochemical mechanisms driving the fluoride enrichment. Majority of the groundwater samples did not meet the potable water criteria as they contained excess (>1.5 mg/L) fluoride, dissolved salts (>500 mg/L) and total hardness (75-924 mg/L). Hydrogeochemical facies of the groundwater samples suggest that rock weathering and evaporation-crystallization control the groundwater composition in the study area with 50-67% of samples belonging to the Ca-HCO3 type and the remaining falling into the mixed Ca-Na-HCO3 or Ca-Mg-Cl type. The saturation index values indicated that the groundwater in the study area is oversaturated with respect to calcite and under-saturated with respect to fluorite. The deficiency of calcium ion concentration in the groundwater from calcite precipitation favors fluorite dissolution leading to excess fluoride concentration.