Sample records for mieu selekcijai latvij

  1. Adult Survivorship of the Dengue Mosquito Aedes aegypti Varies Seasonally in Central Vietnam

    PubMed Central

    Hugo, Leon E.; Jeffery, Jason A. L.; Trewin, Brendan J.; Wockner, Leesa F.; Thi Yen, Nguyen; Le, Nguyen Hoang; Nghia, Le Trung; Hine, Emma; Ryan, Peter A.; Kay, Brian H.

    2014-01-01

    The survival characteristics of the mosquito Aedes aegypti affect transmission rates of dengue because transmission requires infected mosquitoes to survive long enough for the virus to infect the salivary glands. Mosquito survival is assumed to be high in tropical, dengue endemic, countries like Vietnam. However, the survival rates of wild populations of mosquitoes are seldom measured due the difficulty of predicting mosquito age. Hon Mieu Island in central Vietnam is the site of a pilot release of Ae. aegypti infected with a strain of Wolbachia pipientis bacteria (wMelPop) that induces virus interference and mosquito life-shortening. We used the most accurate mosquito age grading approach, transcriptional profiling, to establish the survival patterns of the mosquito population from the population age structure. Furthermore, estimations were validated on mosquitoes released into a large semi-field environment consisting of an enclosed house, garden and yard to incorporate natural environmental variability. Mosquito survival was highest during the dry/cool (January-April) and dry/hot (May-August) seasons, when 92 and 64% of Hon Mieu mosquitoes had survived to an age that they were able to transmit dengue (12 d), respectively. This was reduced to 29% during the wet/cool season from September to December. The presence of Ae. aegypti older than 12 d during each season is likely to facilitate the observed continuity of dengue transmission in the region. We provide season specific Ae. aegypti survival models for improved dengue epidemiology and evaluation of mosquito control strategies that aim to reduce mosquito survival to break the dengue transmission cycle. PMID:24551251

  2. The Development and Design of Engineering Economic Indicator System for Nanotechnology Industry Product Manufacturing: A Case Study of Latvia / Inženierekonomisko Rādītāju Sistēmas Attīstība Un Izveide Nanotehnoloģiju Industrijas Produktu Ražošanai: Latvijas Pieredze

    NASA Astrophysics Data System (ADS)

    Geipele, I.; Staube, T.; Ciemleja, G.; Geipele, S.; Zeltins, N.; Ekmanis, J.

    2015-10-01

    The current scientific paper is developed to continue the research on further commercialisation of the nanotechnology products of manufacturing industries in Latvia. To create the system of engineering economic indicators for multifunctional nanocoating technologies, the scientific indicators and their theoretical justification have been used, the issues from the experts' analysis and survey of the Latvian companies operating in the nanotechnology industry have been summarised. Zinātniskā publikācija ir sagatavota kā turpinājums nanotehnoloģiju industrijas produktu komercializācijas pētījumam Latvijā. Lai izveidotu inženierekonomisko rādītāju sistēmu daudzfunkcionālajām nano-pārklājumu tehnoloģijām tiek izmantoti zinātniskie indikatori, to teorētiskais pamatojums, kā arī Latvijas inovatīvo daudzfunkcionālo materiālu ražotāju aptaujas un ekspertinterviju rezultāti.

  3. Field evaluation of the establishment potential of wMelPop Wolbachia in Australia and Vietnam for dengue control.

    PubMed

    Nguyen, Tran Hien; Nguyen, H Le; Nguyen, Thu Yen; Vu, Sinh Nam; Tran, Nhu Duong; Le, T N; Vien, Quang Mai; Bui, T C; Le, Huu Tho; Kutcher, Simon; Hurst, Tim P; Duong, T T H; Jeffery, Jason A L; Darbro, Jonathan M; Kay, B H; Iturbe-Ormaetxe, Iñaki; Popovici, Jean; Montgomery, Brian L; Turley, Andrew P; Zigterman, Flora; Cook, Helen; Cook, Peter E; Johnson, Petrina H; Ryan, Peter A; Paton, Chris J; Ritchie, Scott A; Simmons, Cameron P; O'Neill, Scott L; Hoffmann, Ary A

    2015-10-28

    Introduced Wolbachia bacteria can influence the susceptibility of Aedes aegypti mosquitoes to arboviral infections as well as having detrimental effects on host fitness. Previous field trials demonstrated that the wMel strain of Wolbachia effectively and durably invades Ae. aegypti populations. Here we report on trials of a second strain, wMelPop-PGYP Wolbachia, in field sites in northern Australia (Machans Beach and Babinda) and central Vietnam (Tri Nguyen, Hon Mieu Island), each with contrasting natural Ae. aegypti densities. Mosquitoes were released at the adult or pupal stages for different lengths of time at the sites depending on changes in Wolbachia frequency as assessed through PCR assays of material collected through Biogents-Sentinel (BG-S) traps and ovitraps. Adult numbers were also monitored through BG-S traps. Changes in Wolbachia frequency were compared across hamlets or house blocks. Releases of adult wMelPop-Ae. aegypti resulted in the transient invasion of wMelPop in all three field sites. Invasion at the Australian sites was heterogeneous, reflecting a slower rate of invasion in locations where background mosquito numbers were high. In contrast, invasion across Tri Nguyen was relatively uniform. After cessation of releases, the frequency of wMelPop declined in all sites, most rapidly in Babinda and Tri Nguyen. Within Machans Beach the rate of decrease varied among areas, and wMelPop was detected for several months in an area with a relatively low mosquito density. These findings highlight challenges associated with releasing Wolbachia-Ae. aegypti combinations with low fitness, albeit strong virus interference properties, as a means of sustainable control of dengue virus transmission.

  4. Analytical Treatment of Forecasts of Electric Energy Consumption in Latvia

    NASA Astrophysics Data System (ADS)

    Balodis, M.; Gavars, V.; Andersons, J.

    2014-06-01

    In the paper, the changes in electric energy consumption are analyzed as associated with structural changes in the Latvian economy of postsocialistic period. To the analysis, a particular approach is applied, which consists in comparison of the basic and specific electricity consumption indices in West-, Central-, and East-European states for the time span of 1990-2010, with differences and tendencies of changes revealed. Tendencies of the type are determined for the electric energy consumption in Latvia, and recommendations are given for the use of such indices in the relevant forecasts. Rakstā apskatītas elektroenerģijas patēriņa izmaiņas, kas saistītas ar Latvijas postsociālisma perioda ekonomikas strukturālām izmaiņām. Rakstā dota Latvijas galveno elektroenerģijas patēriņa indikatoru analīze, lietojot īpašu pieeju - Rietumeiropas, Centrāleiropas un Austrumeiropas valstu indikatoru salīdzinājumu. Analizēts periods no 1990. gada līdz 2010. gadam. Salīdzināti Eiropas valstu grupu īpatnējie elektroenerģijas patēriņa indikatori un noskaidrotas to atšķirības un izmaiņu tendences. Noteiktas elektroenerģijas patēriņa izmaiņu tendences Latvijā. Dotas rekomendācijas par šo indikatoru izmantošanu elektroenerģijas patēriņa prognozēšanā. 07.05.2014.

  5. Characterizing the Aedes aegypti Population in a Vietnamese Village in Preparation for a Wolbachia-Based Mosquito Control Strategy to Eliminate Dengue

    PubMed Central

    Jeffery, Jason A. L.; Thi Yen, Nguyen; Nam, Vu Sinh; Nghia, Le Trung; Hoffmann, Ary A.; Kay, Brian H.; Ryan, Peter A.

    2009-01-01

    Background A life-shortening strain of the obligate intracellular bacteria Wolbachia, called wMelPop, is seen as a promising new tool for the control of Aedes aegypti. However, developing a vector control strategy based on the release of mosquitoes transinfected with wMelPop requires detailed knowledge of the demographics of the target population. Methodology/Principal Findings In Tri Nguyen village (611 households) on Hon Mieu Island in central Vietnam, we conducted nine quantitative entomologic surveys over 14 months to determine if Ae. aegypti populations were spatially and temporally homogenous, and to estimate population size. There was no obvious relationship between mosquito (larval, pupal or adult) abundance and temperature and rainfall, and no area of the village supported consistently high numbers of mosquitoes. In almost all surveys, key premises produced high numbers of Ae. aegypti. However, these premises were not consistent between surveys. For an intervention based on a single release of wMelPop-infected Ae. aegypti, release ratios of infected to uninfected adult mosquitoes of all age classes are estimated to be 1.8–6.7∶1 for gravid females (and similarly aged males) or teneral adults, respectively. We calculated that adult female mosquito abundance in Tri Nguyen village could range from 1.1 to 43.3 individuals of all age classes per house. Thus, an intervention could require the release of 2–78 wMelPop-infected gravid females and similarly aged males per house, or 7–290 infected teneral female and male mosquitoes per house. Conclusions/Significance Given the variability we encountered, this study highlights the importance of multiple entomologic surveys when evaluating the spatial structure of a vector population or estimating population size. If a single release of wMelPop-infected Ae. aegypti were to occur when wild Ae. aegypti abundance was at its maximum, a preintervention control program would be necessary to ensure that there was no

  6. Identity of Innovative Multifunctional Material Manufacturing Business in Latvia / Inovatīvu Daudzfunkcionālo Materiālu Ražotāju Identitāte Latvijā

    NASA Astrophysics Data System (ADS)

    Geipele, I.; Staube, T.; Ciemleja, G.; Zeltins, N.; Ekmanis, Yu.

    2015-08-01

    The publication comprises the results from the practical scientific investigation to define the profile and distinctions of the Latvian innovative multifunctional material manufacturing industry. The research is carried out by a holistic approach, including expert interviews, qualitative analysis of the official register data, practical survey, and financial data analysis. The paper seeks to give the detailed data on a technological profile of the mentioned representative companies, if there is a synergy or tough competition in the Latvian market. The current research is topical, because it is unique and does not have analogues in Latvia, and the research is timely due to correspondence with recently stated Research and Innovation Strategies for Smart Specialisation in Latvia. The main findings are associated with recognition of the factors that make impact on commercialisation of the finished goods, obtained financial results and planned directions of development of the respondent companies. Publikācija sniedz veiktā zinātniski praktiskā pētījuma rezultātus, kura ietvaros tika noteikts Latvijas inovatīvu daudzfunkcionālo materiālu ražotāju darbības profils un identitāte. Pētījumā tika izmantota kompleksās analīzes metode, kas ietvēra ekspertu intervijas, uzņēmumu oficiāli reģistrēto datu kvalitatīvo analīzi, zinātniski praktisko aptauju, kā arī pētāmo uzņēmumu finanšu darbības rezultātu analīzi. Zinātniskais darbs sniedz izsmeļošu informāciju par mērķa uzņēmumu tehnoloģisko profilu un pēta, vai Latvijas mērķa ražošanas nozarē ir sinerģijas vai sīvās konkurences pazīmes. Šim zinātniskajam pētījumam ir noteikta aktualitāte saskaņā ar tā unikalitāti Latvijas valsts mērogā un atbilstība Viedās specializācijas stratēģijai. Pētījuma galvenie secinājumi ir saistīti ar uzņēmumu produkcijas komercializācijas ietekmējošo faktoru apzināšanu, sasniegtajiem finansiālajiem rezultātiem un plānotajiem attīstības virzieniem.

  7. Res-E Support Policies in the Baltic States: Electricity Price Aspect (Part II)

    NASA Astrophysics Data System (ADS)

    Bobinaite, V.; Priedite, I.

    2015-04-01

    Increasing volumes of electricity derived from renewable energy sources (RES-E) affect the electricity market prices and the prices for final electricity consumers in the Baltic States. The results of a multivariate regression analysis show that in 2013 the RES-E contributed to decreasing the electricity market prices in the Baltic States. However, the final electricity consumers pay for the promotion of RES-E through the approved RES-E component which has a tendency to increase. It is estimated that in 2013 the net benefits from the wind electricity promotion were achieved in Lithuania and Latvia while the net cost - in Estonia. This suggests that the economic efficiency of the wind electricity support scheme based on the application of feed-in tariffs was higher than that based on the feed-in premium. Rakstā analizēta elektroenerģijas ražošanas no atjaunojamiem energoresursiem (AER-E) palielināšanas ietekme uz elektroenerģijas tirgus cenu un gala cenu elektroenerģijas lietotājiem Baltijas valstīs. Daudzfaktoru regresijas analīzes rezultāti atklāja, ka AER-E 2013. gadā varētu samazināt elektroenerģijas tirgus cenas Baltijas valstīs. Tomēr jāņem vērā, ka elektroenerģijas lietotāja gala cenā ir iekļauta AER-E atbalsta komponente, kurai ir raksturīgi palielināties. Aprēķināts, ka no vēja elektroenerģijas ražošanas Latvijā un Lietuvā tika iegūta tīrā peļņa, bet Igaunijā tikai nosedza pašizmaksu. Tas liecina, ka vēja elektroenerģijas atbalsta shēmai, kas balstīta uz obligātā iepirkuma atbalsta principu, ir augstāka ekonomiskā efektivitāte, nekā atbalsta shēmai, kas balstīta uz piemaksu par no AER saražoto elektroenerģiju obligātā iepirkuma ietvaros.

  8. Latvian Waste Management Modelling in View of Environmental Impact Reduction / Latvijas Atkritumu SAIMNIECĪBAS ATTĪSTĪBA un TĀS RADĪTĀS Ietekmes UZ Vidi SAMAZINĀŠANAS MODELĒŠANA

    NASA Astrophysics Data System (ADS)

    Teibe, I.; Bendere, R.; Arina, D.

    2013-12-01

    In the work, the life-cycle assessment approach is applied to the planning of waste management development in a seaside region (Piejūra) using the Waste Management Planning System (WAMPS) program. In Latvia, the measures to be taken for the climate change mitigation are of utmost importance - especially as related to the WM performance, since a disposal of biodegradable waste presents the primary source of GHG emissions. To reduce the amount of such waste is therefore one of the most significant goals in the State WM plan for 2013-2020, whose adoption is the greatest challenge for municipalities. The authors analyse seven models which involve widely employed biomass processing methods, are based on experimental data and intended for minimising the direct disposal of organic mass at the solid waste landfills. The numerical results obtained evidence that the thermal or biotechnological treatment of organic waste substantially reduces the negative environmental impact of WM practices - by up to 6% as compared with the currently existing. Klimata pārmaiņu samazināšanas pasākumi Latvijā atkritumu saimniecības sektorā ir īpaši svarīgi. jo bioloģiski sadalāmo atkritumu apglabāšana ir viens no būtiskākajiem SEG emisiju avotiem valstī. Pētījumā modelēti virkne sadzīves atkritumu apsaimniekošanas modeļi. kas ietver plašāk izmantotās biomasas pārstrādes metodes un samazina tiešu organiskās masas apglabāšanu cieto sadzīves atkritumu poligonos. Atkritumu apsaimniekošanas modeļu radītās vides ietekmes novērtēšanai izmantota WAMPS (Waste Management Planning System) programma, kas balstīta uz atkritumu apsaimniekošanas procesu dzīves cikla novērtējumu vienā no desmit Latvijas atkritumu apsaimniekošanas reģioniem - Piejūra. Iegūtie kvantitatīvie rezultāti norāda. ka organiskās atkritumu masas pārstrāde un stabilizēšana, izmantojot biotehnoloģijas vai termisko pārstrādi, būtiski samazina atkritumu apsaimniekošanas rad

  9. Sail-Type Wind Turbine for Autonomous Power Supplay: Possible Use in Latvia

    NASA Astrophysics Data System (ADS)

    Sakipova, S.; Jakovics, A.

    2014-12-01

    Under the conditions of continuous increase in the energy consumption, sharply rising prices of basic energy products (gas, oil, coal), deterioration of environment, etc., it is of vital importance to develop methods and techniques for heat and power generation from renewables. The paper considers the possibility to use a sail-type wind turbine for autonomous power supply in Latvia, taking into account its climatic conditions. The authors discuss the problems of developing a turbine of the type that would operate efficiently at low winds, being primarily designed to supply power to small buildings and farms distant from centralized electricity networks. The authors consider aerodynamic characteristics of such a turbine and the dependence of the thrust moment of its pilot model on the airflow rate at different angles of attack. The pilot model with a changeable blade shape has been tested and shows a good performance. Darbs veltīts vienam no atjaunojamo enerģiju veidiem - vēja enerģijai, analizētas tās izmantošanas iespējas. Vispirms īsi raksturota vēja enerģijas izmantošana pasaulē, kā arī vērtētas izmantošanas perspektīvas no inženiertehniskā un klimatisko apstākļu viedokļa. Turpinājumā raksturota situācija Latvijā, t. sk., arī vēja potenciāla pieejamība dažādos reģionos, kā arī vēja enerģijas izmantošanas efektivitāti raksturojošie lielumi. Konstatējot problēmu, rast vēja turbīnu risinājumus Latvijas apstākļiem ar maziem vidējiem vēja ātrumiem, izveidots buras tipa turbīnas modelis. Šī modeļa raksturlielumu izpēte veikta vēja tunelī Karagandas universitātē, konstatējot relatīvi labus efektivitātes rādītājus tiešai un pretējai vēja plūsmai. Izmantojot mērījumu rezultātus, ierosināti sistēmas uzlabojumi, kurus plānots pētīt turpmāk. Šādas sistēmas potenciāli var rast lietojumu tur, kur nepieciešami autonomi enerģijas avoti.

  10. Assessment of Wind Shear and Wind Energy Potential in the Baltic Sea Region of Latvia

    NASA Astrophysics Data System (ADS)

    Bezrukovs, V.; Bezrukovs, Vl.; Zacepins, A.; Komashilovs, V.

    2015-04-01

    vēja sezonālām ātruma svārstībām tika iegūti līdz 160 metru augstumam. Pētījuma rezultāti par vēja ātruma sadalījumu līdz 200 metriem, ļauj novērtēt vēja enerģijas potenciālu Latvijā, un tiem ir jāpalīdz noteikt perspektīvākās vietas vēja turbīnu izvietošanai.