992 resultados para q-Heat Equation
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Protein homeostasis is essential for cells to prosper and survive. Various forms of stress, such as elevated temperatures, oxidative stress, heavy metals or bacterial infections cause protein damage, which might lead to improper folding and formation of toxic protein aggregates. Protein aggregation is associated with serious pathological conditions such as Alzheimer’s and Huntington’s disease. The heat shock response is a defense mechanism that protects the cell against protein-damaging stress. Its ancient origin and high conservation among eukaryotes suggest that the response is crucial for survival. The main regulator of the heat shock response is the transcription factor heat shock factor 1 (HSF1), which induces transcription of genes encoding protective molecular chaperones. In vertebrates, a family of four HSFs exists (HSF1-4), with versatile functions not only in coping with acute stress, but also in development, longevity and cancer. Thus, knowledge of the HSFs will aid in our understanding on how cells survive suboptimal circumstances, but will also provide insights into normal physiological processes as well as diseaseassociated conditions. In this study, the function and regulation of HSF2 have been investigated. Earlier gene inactivation experiments in mice have revealed roles for HSF2 in development, particularly in corticogenesis and spermatogenesis. Here, we demonstrate that HSF2 holds a role also in the heat shock response and influences stress-induced expression of heat shock proteins. Intriguingly, DNA-binding activity of HSF2 upon stress was dependent on the presence of intact HSF1, suggesting functional interplay between HSF1 and HSF2. The underlying mechanism for this phenomenon could be configuration of heterotrimers between the two factors, a possibility that was experimentally verified. By changing the levels of HSF2, the expression of HSF1-HSF2 heterotrimer target genes was altered, implementing HSF2 as a modulator of HSF-mediated transcription. The results further indicate that HSF2 activity is dependent on its concentration, which led us to ask the question of how accurate HSF2 levels are achieved. Using mouse spermatogenesis as a model system, HSF2 was found to be under direct control of miR-18, a miRNA belonging to the miR-17~92 cluster/Oncomir-1 and whose physiological function had remained unclear. Investigations on spermatogenesis are severely hampered by the lack of cell systems that would mimic the complex differentiation processes that constitute male germ cell development. Therefore, to verify that HSF2 is regulated by miR-18 in spermatogenesis, a novel method named T-GIST (Transfection of Germ cells in Intact Seminiferous Tubules) was developed. Employing this method, the functional consequences of miR-18-mediated regulation in vivo were demonstrated; inhibition of miR- 18 led to increased expression of HSF2 and altered the expression of HSF2 target genes Ssty2 and Speer4a. Consequently, the results link miR-18 to HSF2-mediated processes such as germ cell maturation and quality control and provide miR-18 with a physiological role in gene expression during spermatogenesis.Taken together, this study presents compelling evidence that HSF2 is a transcriptional regulator in the heat shock response and establishes the concept of physical interplay between HSF2 and HSF1 and functional consequences thereof. This is also the first study describing miRNA-mediated regulation of an HSF.
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Kainuun ELY-keskus ja alueen TE-toimistot yhdessä Kainuun ammattiopiston kanssa kartoittivat kainuulaisten ICT-alan yritysten työvoima-, koulutus- ja osaamistarpeita sekä toimialan kehitysnäkymiä. Työvoiman ja koulutuksen tarvetutkimuksen (TKTT) haastatteluja tehtiin alkusyksyn 2011 aikana yhteensä 21 yrityksessä. Näistä 16 tehtiin samanaikaisesti C&Q-profession osaamistarvekartoitus. Kyselyjen tuloksia käsiteltiin lokakuussa järjestetyssä asiantuntijaraadissa. Haastatelluista yrityksistä näyttää löytyvän kasvuhalukkuutta. Paitsi että yritykset ilmoittivat olevansa kasvuhakuisia, niin 15 yritystä 21:stä arvioi henkilöstömääränsä kasvavan seuraavan vuoden aikana. Yritykset työllistivät haastatteluhetkellä yhteensä 715 henkeä. Niiden yhteenlasketun henkilöstömäärän arvioitiin seuraavan vuoden aikana kasvavan yhteensä 65 hengellä eli 9,1 %. Suomen talouden epävarmoista kehitysnäkymistä huolimatta kainuulaisten ICT-alan yritysten suhdanneodotukset vuodeksi eteenpäin olivat positiiviset. Tarkempia suunnitelmia rekrytoida uutta työvoimaa oli kymmenellä yrityksellä. Heti tai vuoden kuluessa oli tarvetta palkata yhteensä 28 henkilöä. Eniten oli tarvetta atk-suunnittelijoille, joko ohjelmoijiksi tai ohjelmistosuunnittelijoiksi. Yrityksissä oli lisäksi kysyntää alan insinööreille ja teknikoille ja myös myyntitehtäviin haettiin osaajia. Työvoiman tarve on kasvussa myös pidemmällä tähtäimellä. Kyselyn perusteella työvoiman saatavuudessa ICT-alalla ei ainakaan vielä näytä olevan suuria ongelmia. ICT-alan kehitys on nopeaa ja alalla on osattava soveltaa teknologiaa asiakkaiden monenlaisiin tarpeisiin. Alan ammattilaisten tärkeintä osaamista on oman alansa asiantuntijuus. Yritykset nostivat muiksi tärkeiksi kvalifikaatioiksi muun muassa toimialan teknisen kehityksen seuraamisen ja ajantasaisen osaamisen varmistamisen sekä ennakoivan ajattelu- ja toimintatavan. Nykyisen osaamisen lisäksi yritysten henkilökunnalla pitäisi olla enemmän vuorovaikutus-, viestintä- ja kommunikointitaitoja sekä asiakaspalveluun liittyviä taitoja. Muutoksia osaamistarpeisiin tuo esimerkiksi ohjelmistosuunnittelun ja sovellusten käytön siirtyminen mobiilialustoille ja ns. pilvipalveluihin. Yrityksillä oli monenlaisia koulutustarpeita nykyiselle henkilöstölle. Asiantuntijaraadissa eri tarpeet yhdistettiin seuraavanlaisiksi koulutuskokonaisuuksiksi: ohjelmointi ja projektiosaaminen, tuotanto ja kielikoulutus, myynti ja markkinointi, asiakastarpeiden kartoitus ja tuotekehitys sekä esimiesosaaminen. Alan yritysten yhteistyön tiivistäminen muun muassa IT-poolin kautta nähtiin edelleen tarpeellisena. Yhteistyöhön oppilaitosten kanssa esimerkiksi työharjoittelujen suhteen oltiin pääasiassa tyytyväisiä. Oppilaitoksista valmistuneilla nähtiin olevan perusvalmiudet kutakuinkin kohdallaan. Puutteita oli projektityöskentelyvalmiuksissa ja projektinhallintataidoissa, ohjelmistotekniikan prosessikokonaisuuksien hallinnassa, tietokantapalvelujen tekniikan suunnittelussa sekä tiimityöskentelytaidoissa.
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Most studies on measures of transpiration of plants, especially woody fruit, relies on methods of heat supply in the trunk. This study aimed to calibrate the Thermal Dissipation Probe Method (TDP) to estimate the transpiration, study the effects of natural thermal gradients and determine the relation between outside diameter and area of xylem in 'Valencia' orange young plants. TDP were installed in 40 orange plants of 15 months old, planted in boxes of 500 L, in a greenhouse. It was tested the correction of the natural thermal differences (DTN) for the estimation based on two unheated probes. The area of the conductive section was related to the outside diameter of the stem by means of polynomial regression. The equation for estimation of sap flow was calibrated having as standard lysimeter measures of a representative plant. The angular coefficient of the equation for estimating sap flow was adjusted by minimizing the absolute deviation between the sap flow and daily transpiration measured by lysimeter. Based on these results, it was concluded that the method of TDP, adjusting the original calibration and correction of the DTN, was effective in transpiration assessment.
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The state of Ceará, Brazil, has 75% of its area covered by Brazilian semiarid, with its peculiar features. In this state, the dams are constituted in water structure of strategic importance, ensuring, both in time and space, the development and supply of water to population. However, construction of reservoirs results in various impacts that should be carefully observed when deciding on their implementation. One of the impacts identified as negative is the increased evaporation, which constitutes a major component of water balance in reservoirs, especially in arid regions. Several methods for estimating evaporation have been proposed over time, many of them deriving from the Penman equation. This study evaluated six different methods for estimating evaporation in order to determine the most suitable for use in hydrological models for water balance in reservoirs in the state of Ceará. The tested methods were proposed by Penman, Kohler-Nordenson-Fox, Priestley-Taylor, deBruim-Keijman, Brutsaert-Stricker and deBruim. The methods presented good performance when tested for water balance during the dry season, and the Priestley-Taylor was the most appropriate, since the data from de simulated water balance with evaporation estimated by this method were the closest of the water balance data observed from measures of reservoir level and the elevation-volume curve provided by the Company of Management of Water Resources of the state of Ceará - COGERH.
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The purpose of this paper was to observe the use of bedding (wood shavings) in physiological variables that indicate thermal stress in gestating sows. The experiment was conducted in order to evaluate the effect of two types of floor (concrete and wood shavings). Worse microclimatic conditions were observed in bedding systems (P<0.05), with an increase in temperature and enthalpy of 1.14 ºC and 2.37 kJ.kg dry air-1, respectively. The floor temperature at the dirty area was higher in the bedding presence in comparison to its absence. In spite of the worse microclimatic conditions in the bedding, the rectal temperature did not differ significantly (P>0.05) but the skin surface temperature was higher in the bedding systems. The same occurred with the respiratory rates. The physical characteristics of the floor material influenced the rate of heat loss by conductance. Estimated values were 35.04 and 7.99 W m-2 for the conductive heat loss between the animal and floor for treatments with or without bedding, respectively. The use of bedding in sow rearing has a negative impact on microclimatic conditions, what implies in thermoregulatory damages.
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The aim of this study was to generate maps of intense rainfall equation parameters using interpolated maximum intense rainfall data. The study area comprised Espírito Santo State, Brazil. A total of 59 intense rainfall equations were used to interpolate maximum intense rainfall, with a 1 x 1 km spatial resolution. Maximum intense rainfall was interpolated considering recurrence of 2; 5; 10; 20; 50 and 100 years, and duration of 10; 20; 30; 40; 50; 60; 120; 240; 360; 420; 660; 720; 900; 1,140; 1,380 and 1,440 minutes, resulting in 96 maps of maximum intense rainfall. The used interpolators were inverse distance weighting and ordinary kriging, for which significance level (p-value) and coefficient of determination (R²) were evaluated for the cross-validation data, choosing the method that presented better R² to generate maps. Finally, maps of maximum intense precipitation were used to estimate, cell by cell, the intense rainfall equation parameters. In comparison with literature data, the mean percentage error of estimated intense rainfall equations was 13.8%. Maps of spatialized parameters, obtained in this study, are of simple use; once they are georeferenced, they may be imported into any geographic information system to be used for a specific area of interest.
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After hatching, pullets are transported to brooding area and vaccinated. One day old chicks have not already developed thermoregulation ability; thus, brooding temperature variations may affect pullet quality leading to broiler meat production losses. This research aimed to calculate sensible heat loss in one day old pullets in hatching area and vaccination room. Ten one day old pullets were randomly selected from hatching area of a commercial hatchery. Infrared images were used to calculate bird surface temperature. Exposure areas for the two conditions were quantified, and both air temperature and wind speed was recorded. Total sensible heat loss was calculated as heat loss by radiation plus heat loss by convection. It was found that heat transfer occurs in different ways at different bird body parts. Total heat loss found for hatching baskets was equivalent to 0.81 J s-1 while for vaccination room was 1.16 J s-1. Pullet nutrition is based on energy loss from brooding to farm, and the overall pullet heat loss from hatchery to farm accepted is 13.95 J s-1. Thus, "starter feed" has relevant excess of energy input. These findings indicate that less energy can be used in initial feed, once heat loss is lower than assumed nowadays. Improved knowledge on these conditions may enhance broiler farm feeding strategies and economics during first rearing week.
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Due to the lack of information concerning maximum rainfall equations for most locations in Mato Grosso do Sul State, the alternative for carrying out hydraulic work projects has been information from meteorological stations closest to the location in which the project is carried out. Alternative methods, such as 24 hours rain disaggregation method from rainfall data due to greater availability of stations and longer observations can work. Based on this approach, the objective of this study was to estimate maximum rainfall equations for Mato Grosso do Sul State by adjusting the 24 hours rain disaggregation method, depending on data obtained from rain gauge stations from Dourado and Campo Grande. For this purpose, data consisting of 105 rainfall stations were used, which are available in the ANA (Water Resources Management National Agency) database. Based on the results we concluded: the intense rainfall equations obtained by pluviogram analysis showed determination coefficient above 99%; and the performance of 24 hours rain disaggregation method was classified as excellent, based on relative average error WILMOTT concordance index (1982).
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Pigs are more sensitive to high environmental temperatures explained by the inability of sweating and panting properly when compared to other species of farmed livestock. The evaporative cooling system might favor the thermal comfort of animals during exposure to extreme environmental heat and reduce the harmful effects of heat stress. The purpose of this study was to assess the sensible heat loss and thermoregulation parameters from lactating sows during summer submitted to two different acclimatization systems: natural and evaporative cooling. The experiment was carried out in a commercial farm with 72 lactating sows. The ambient variables (temperature, relative humidity and air velocity) and sows physiological parameters (rectal temperature, surface temperature and respiratory rate) were monitored and then the sensible heat loss at 21days lactation was calculated. The results of rectal temperature did not differ between treatments. However, the evaporative cooling led to a significant reduction in surface temperature and respiratory rate and a significant increase in the sow's sensible heat loss. It was concluded that the use of evaporative cooling system was essential to increase sensible heat loss; thus, it should reduce the negative effects of heat on the sows' thermoregulation during summer.
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Based on experimental tests, it was obtained the equations for drying, equilibrium moisture content, latent heat of vaporization of water contained in the product and the equation of specific heat of cassava starch pellets, essential parameters for realizing modeling and mathematical simulation of mechanical drying of cassava starch for a new technique proposed, consisting of preformed by pelleting and subsequent artificial drying of starch pellets. Drying tests were conducted in an experimental chamber by varying the air temperature, relative humidity, air velocity and product load. The specific heat of starch was determined by differential scanning calorimetry. The generated equations were validated through regression analysis, finding an appropriate correlation of the data, which indicates that by using these equations, can accurately model and simulate the drying process of cassava starch pellets.
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ABSTRACT Given the need to obtain systems to better control broiler production environment, we performed an experiment with broilers from 1 to 21 days, which were submitted to different intensities and air temperature durations in conditioned wind tunnels and the results were used for validation of afuzzy model. The model was developed using as input variables: duration of heat stress (days), dry bulb air temperature (°C) and as output variable: feed intake (g) weight gain (g) and feed conversion (g.g-1). The inference method used was Mamdani, 20 rules have been prepared and the defuzzification technique used was the Center of Gravity. A satisfactory efficiency in determining productive responses is evidenced in the results obtained in the model simulation, when compared with the experimental data, where R2 values calculated for feed intake, weight gain and feed conversion were 0.998, 0.981 and 0.980, respectively.
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ABSTRACT Global warming increases the occurrence of events such as extreme heat waves. Research on thermal and air conditions affecting broiler-rearing environment are important to evaluate the animal welfare under extreme heat aiming mitigation measures. This study aimed at evaluating the effect of a simulated heat wave, in a climatic chamber, on the thermal and air environment of 42-day-old broilers. One hundred and sixty broilers were housed and reared for 42 days in a climatic chamber; the animals were divided into eight pens. Heat wave simulation was performed on the 42nd day, the period of great impact and data sampling. The analyzed variables were room and litter temperatures, relative humidity, concentrations of oxygen, carbon monoxide and ammonia at each pen. These variables were assessed each two hours, starting at 8 am, simulating a day heating up to 4 pm, when it is reached the maximum temperature. By the results, we concluded that increasing room temperatures promoted a proportional raise in litter temperatures, contributing to ammonia volatilization. In addition, oxygen concentrations decreased with increasing temperatures; and the carbon monoxide was only observed at temperatures above 27.0 °C, relative humidity higher than 88.4% and litter temperatures superior to 30.3 °C.
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Kainuun ELY-keskus ja alueen TE-toimistot kartoittivat yhdessä Kainuun ammattiopiston ja Kajaanin ammattikorkeakoulun kanssa kaivannaisalalla toimivien yritysten työvoima-, koulutus- ja osaamistarpeita sekä alan kehitysnäkymiä. Alkuvuodesta 2012 tehtyjen haastattelujen kohteena olivat kaivos- ja luonnonkiviteollisuuden yritykset sekä kaivosteollisuuden urakoitsijat. Työvoiman ja koulutuksen tarvekartoitusta (TKTT) varten haastateltiin 22 yritystä, joista osassa tehtiin samanaikaisesti C&Q-osaamistarvekartoitus. Kainuussa on viime vuosina koettu kaivosbuumi. Kaivannaistoiminnan liikevaihto ja henkilöstön määrä ovat kasvaneet voimakkaasti. Haastatellut yritykset arvioivat alan suhdannetilanteen ja näkymät vuodeksi eteenpäin valoisiksi. Yrityksissä on kasvuhalukkuutta ja 12 yritystä 22:sta arvioikin henkilöstömääränsä kasvavan seuraavan vuoden aikana. Yritykset työllistivät haastatteluhetkellä Kainuun toimipaikoissa 888 henkilöä ja niiden yhteenlasketun henkilöstömäärän arvioitiin seuraavan vuoden aikana kasvavan yhteensä 139 hengellä eli 15,7 %. Työvoimantarve yrityksissä on kasvussa myös pidemmällä tähtäimellä. Yritykset ilmoittivat tarkemmin yhteensä 100 henkilön lisäystarpeesta heti tai vuoden kuluessa. Eniten kysyntää oli kenttäoperaattoreille, koneenasentajille, maarakennuskoneiden kuljettajille ja muovihitsaajille. Myös eri alojen insinöörejä ja teknikkoja haettiin työnjohto- ja asiantuntijatehtäviin. Työvoiman saatavuudessa on kaivosalalla jonkin verran ongelmia. Tässä selvityksessä yleisimmäksi rekrytointion¬gelman syyksi nousi työnhakijoiden riittämätön työkokemus. Keskeisimpänä muutoksena kaivosalalla on teknologian kehittyminen, mikä näkyy muun muassa tietotekniikan lisääntymisenä työkoneissa. Työssä vaaditaan nykyisin tietoteknisiä taitoja ja kunnossapito-osaamista. Työnantajat nostivat tärkeiksi osaamisvaatimuksiksi myös monia työntekijöiden henkilökohtaisiin ominaisuuksiin ja asenteisiin liittyviä tekijöitä, kuten joustavuuden työorganisaation tarpeista lähtien sekä oma-aloitteisuuden ja itsenäisen otteen työhön. Tulevaisuudessa arvioidaan tarvittavan nykyistä enemmän ympäristöosaamista sekä maarakennukseen ja maanmittaukseen liittyvää osaamista. Yritysten nykyiselle henkilöstölle ilmeni koulutustarpeita muun muassa sähköalan, panostajan sekä työnjohto- ja esimieskoulutuksiin. Yrityksissä oli myös tarpeita erilaisille korttikoulutuksille ja muille lyhytkoulutuksille.
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Following over 170+ pages and additional appendixes are formed based on content of Course: Fundamentals of Heat Transfer. Mainly this summarizes relevant parts on Book of Fundamentals of Heat and Mass Transfer (Incropera), but also other references introducing the same concepts are included. Student’s point of view has been consideredwith following highlights: (1) Relevant topics are presented in a nutshell to provide fast digestion of principles of heat transfer. (2) Appendixes include terminology dictionary. (3) Totally 22 illustrating examples are connecting theory to practical applications and quantifying heat transfer to understandable forms as: temperatures, heat transfer rates, heat fluxes, resistances and etc. (4) Most important Learning outcomes are presented for each topic separately. The Book, Fundamentals of Heat and Mass Transfer (Incropera), is certainly recommended for those going beyond basic knowledge of heat transfer. Lecture Notes consists of four primary content-wise objectives: (1) Give understanding to physical mechanisms of heat transfer, (2)Present basic concepts and terminology relevant for conduction, convection and radiation (3) Introduce thermal performance analysis methods for steady state and transient conduction systems. (4) Provide fast-to-digest phenomenological understanding required for basic design of thermal models
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In ship and offshore terminal construction, welded cross sections are thick and the number of welds very high. Consequently, there are two aspects of great importance; cost and heat input. Reduction in the welding operation time decreases the costs of the work force and avoids excessive heat, preventing distortion and other weld defects. The need to increase productivity while using a single wire in the GMAW process has led to the use of a high current and voltage to improve the melting rate. Unfortunately, this also increases the heat input. Innovative GMAW processes, mostly implemented for sheet plate sections, have shown significant reduction in heat input (Q), low distortion and increase in welding speed. The aim of this study is to investigate adaptive pulsed GMAW processes and assess relevant applications in the high power range, considering possible benefits when welding thicker sections and high yield strength steel. The study experimentally tests the usability of adaptive welding processes and evaluates their effects on weld properties, penetration and shapes of the weld bead.The study first briefly reviews adaptive GMAW to evaluate different approaches and their applications and to identify benefits in adaptive pulsed. Experiments are then performed using Synergic Pulsed GMAW, WiseFusionTM and Synergic GMAW processes to weld a T-joint in a horizontal position (PB). The air gap between the parts ranges from 0 to 2.5 mm. The base materials are structural steel grade S355MC and filler material G3Si1. The experiment investigates heat input, mechanical properties and microstructure of the welded joint. Analysis of the literature reveals that different approaches have been suggested using advanced digital power sources with accurate waveform, current, voltage, and feedback control. In addition, studies have clearly indicated the efficiency of lower energy welding processes. Interest in the high power range is growing and a number of different approaches have been suggested. The welding experiments in this study reveal a significant reduction of heat input and a weld microstructure with the presence of acicular ferrite (AF) beneficial for resistance to crack propagation. The WiseFusion bead had higher dilution, due to the weld bead shape, and low defects. Adaptive pulse GMAW processes can be a favoured choice when welding structures with many welded joints. The total heat reduction mitigates residual stresses and the bead shape allows a higher amperage limit. The stability of the arc during the process is virtually spatter free and allows an increase in welding speed.