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11.
The economy of the Murmansk region in Russia is based on energy intensive industry, mainly metallurgies, and consequently, the region is highly dependant on the ageing Kola nuclear power plant. This interdependence together with other weaknesses in the regional energy system creates threats to the energy supply security of the region. This paper analyses the internal and external threats influencing the region and presents potential solutions. Scenarios further illustrate possible future paths these potential solutions could deliver by the year 2025. 相似文献
12.
Dahlsten E Korkeala H Somervuo P Lindström M 《International journal of food microbiology》2008,124(1):108-111
Groups I (proteolytic) and II (nonproteolytic) C. botulinum are genetically and physiologically distinct groups of organisms, with both groups being involved with human botulism. Due to differences in spore heat resistance and growth characteristics, the two groups possess different types of human health risks through foods, drink, and the environment. The epidemiology of human botulism due to Groups I and II C. botulinum is poorly understood, largely due to insufficient characterization of disease isolates, and warrants thorough outbreak investigation with a particular attention to discrimination between the different physiological groups of C. botulinum. In this study, a PCR assay was developed to discriminate between Group I and Group II C. botulinum. The assay is based on the fldB associated with phenylalanine metabolism in proteolytic clostridia, and employs an internal amplification control targeted to conservative regions of 16S rrn in Groups I and II C. botulinum. The assay correctly identified all 36 Group I and 24 Group II C. botulinum strains, possessing a 100% exclusivity and inclusivity. The assay provides a substantial improvement in discriminating between the Groups I and II C. botulinum, which traditionally is based on a time-consuming and error-prone culture method. Differentiation between the physiological groups of C. botulinum is an essential step in investigation of human botulism outbreaks, and should be considered as a diagnostic corner-stone in order to improve our epidemiological understanding of human botulism. 相似文献
13.
Miia Ronimus Kenneth Eklund Jari Westerholm Ritva Ketonen Heikki Lyytinen 《Journal of Computer Assisted Learning》2020,36(6):1011-1025
We used a randomized controlled trial to investigate if a mobile game, GraphoLearn (GL), could effectively support the learning of first graders (N = 70), who have severe difficulties in reading and spelling. We studied the effects of two versions of the game: GL Reading, which focused on training letter-sound correspondence and word reading; and GL Spelling, which included additional training in phonological skills and spelling. During the spring of first grade, the children trained with tablet computers which they could carry with them during the six-week intervention. The average exposure time to training was 5 hr 44 min. The results revealed no differences in the development of reading or spelling skills between GL players and the control group. However, pre-training self-efficacy moderated the effect among GL Reading players: children with high self-efficacy developed more than the control group in word reading fluency, whereas children with low self-efficacy developed less than the control group in spelling. 相似文献
14.
Influence of microbes on the mobilization, toxicity and biomethylation of arsenic in soil. 总被引:6,自引:0,他引:6
R Turpeinen M Pantsar-Kallio M H?ggblom T Kairesalo 《The Science of the total environment》1999,236(1-3):173-180
To understand the effects of microbial activity on the mobilization and speciation of arsenic in soil, the cycling of arsenic was studied in microcosm experiments under laboratory conditions. Particular attention was paid to the biomethylation of arsenic and to the toxicity of inorganic and organic arsenic species for microbes. Microbes enhanced mobilization of arsenic from soil by 19-24% compared to formaldehyde inhibited controls. Formation of dissolved methylated arsenic species by microbes was low (< 0.1%) during the 5-day incubation. Even though methylation may function as a detoxification method, it was of minor importance in the soil tested. 相似文献
15.
重点介绍了美卓造纸机械公司研发的Val-Former靴刮刀叠网成形技术、OptiFormer夹网成形器和OptiFlo Ⅱ型流浆箱,以便为使用较高比例的混合废纸且在更高的车速下生产更低定量瓦楞原纸以及挂面纸板时,获得高效、低能耗和理想质量的产品. 相似文献
16.
A.M. Turpeinen M. Kumpu M. Rönnback L. Seppo H. Kautiainen T. Jauhiainen H. Vapaatalo R. Korpela 《Journal of Functional Foods》2009,1(3):260-265
The effects of a spread containing bioactive tripeptides isoleucine–proline–proline (IPP), valine–proline–proline (VPP) and plant sterols were studied in subjects with mild hypertension and elevated LDL cholesterol. Sixty-two subjects consumed 20 g/day spread containing 4.2 mg milk peptides and 2 g plant sterol esters or placebo for 10 weeks. Blood pressure was measured twice a week. Arterial stiffness was assessed by pulse wave analysis and by pulse wave velocity. Blood samples were analysed for serum lipids and high-sensitive CRP. A significant decrease was seen in systolic blood pressure (p = 0.026), but not in diastolic blood pressure (p = 0.53). Total cholesterol (p = 0.003) and LDL cholesterol (p = 0.002) decreased, whereas HDL cholesterol, triacylglycerols and CRP remained unchanged. No overall effects on arterial stiffness were seen. The results suggest that a spread containing bioactive milk peptides and plant sterols has a beneficial effect on two major cardiovascular risk factors, blood pressure and plasma lipids, in hypertensive, dyslipidemic subjects. Functional foods affecting two major risk factors can be valuable tools in managing cardiovascular risk. 相似文献
17.
Group II (non-proteolytic) Clostridium botulinum poses a safety hazard in modern food processing, which consists of mild pasteurization treatments, anaerobic packaging, extended shelf lives and chilled storage. The high risk is reflected in the relatively large number of botulism cases due to group II C. botulinum in commercially produced foods during the past decades. Because of the high prevalence of group II C. botulinum in the environment, food raw materials may carry spores. Although group II spores are less heat-resistant than group I (proteolytic) spores, they can tolerate the heat treatments employed in the chilled food industry. Some food components may actually provide spores with protection from heat. Spore heat resistance should therefore be investigated for each food in order to determine the efficiency of industrial heat treatments. Group II strains are psychrotrophic and thus they are able to grow at refrigeration temperatures. Anaerobic packages and extended shelf lives provide C. botulinum with favourable conditions for growth and toxin formation. As the use of salt and other preservatives in these foods is limited, microbiological safety relies mainly on refrigerated storage. This sets great challenges on the production of chilled packaged foods. To ensure the safety of these foods, more than one factor should safeguard against botulinal growth and toxin production. 相似文献
18.
Miia Turpeinen Jouko Uusitalo Terhi Lehtinen Marita Kailaj?rvi Olavi Pelkonen Jouni Vuorinen Pasi Tapanainen Camilla Stjernschantz Risto Lammintausta Mika Scheinin 《International journal of molecular sciences》2013,14(7):14064-14075
The objective of these investigations was to determine the possible effects of the novel selective estrogen receptor modulator, ospemifene, on cytochrome P450 (CYP)-mediated drug metabolism. Ospemifene underwent testing for possible effects on CYP enzyme activity in human liver microsomes and in isolated human hepatocytes. Based on the results obtained in vitro, three Phase 1 crossover pharmacokinetic studies were conducted in healthy postmenopausal women to assess the in vivo effects of ospemifene on CYP-mediated drug metabolism. Ospemifene and its main metabolites 4-hydroxyospemifene and 4′-hydroxyospemifene weakly inhibited a number of CYPs (CYP2B6, CYP2C9, CYP2C19, CYP2C8, and CYP2D6) in vitro. However, only CYP2C9 activity was inhibited by 4-hydroxyospemifene at clinically relevant concentrations. Induction of CYPs by ospemifene in cultured human hepatocytes was 2.4-fold or less. The in vivo studies showed that ospemifene did not have significant effects on the areas under the plasma concentration-time curves of the tested CYP substrates warfarin (CYP2C9), bupropion (CYP2B6) and omeprazole (CYP2C19), demonstrating that pretreatment with ospemifene did not alter their metabolism. Therefore, the risk that ospemifene will affect the pharmacokinetics of drugs that are substrates for CYP enzymes is low. 相似文献
19.
Matias Ståhle Tuomas Ahola Miia Martinsuo 《International Journal of Project Management》2019,37(1):145-160
The delivery of integrated solutions calls for effective integration across the functional interfaces of the project-based firm (PBF) throughout the solution's life cycle. We scrutinize cross-functional integration in a triadic setting involving the PBF's sales, project operations, and services functions by focusing on the flow of customer information (information from and about customers) across three functional interfaces. Drawing on a qualitative case study, we develop a categorization consisting of four distinct types of integration mechanisms: meetings, IT systems, personal involvement, and processes and rules. Our results show that in the focal PBF, customer information flows are strongest in the sales–project operations interface and weakest in the sales–services interface. Furthermore, sales and services functions were found to rely predominantly on personal involvement mechanisms in transferring customer information. Our results highlight the need to integrate and manage customer information flows, especially between the sales–services interface, when delivering integrated solutions. 相似文献
20.
Influence and CFD analysis of cooling air velocity on the purification of aqueous nickel sulfate solutions by freezing 下载免费PDF全文
Mehdi Hasan Roman Filimonov Miia John Joonas Sorvari Marjatta Louhi‐Kultanen 《American Institute of Chemical Engineers》2018,64(1):200-208
Finite energy resources and their rapidly waning imprint necessitate a sustainable wastewater treatment method. Nature could be exploited to freeze wastewater in locations which experience subzero temperatures during winter. The two most vital components that influence the efficiency of natural freezing are the ambient temperature and air velocity. The turbulent and unsteady air‐cooled natural freezing is simulated for ice crystallization from 0.1 wt % and 1 wt % NiSO4 (aq) solutions. The efficiency of natural freezing is tested for different air velocities (2 ms?1, 5 ms?1) and levels of undercooling (ΔT = 0.5°C, 1°C) from the freezing temperature of the corresponding solution. The airflow in the winter simulator is modeled by computational fluid dynamics to investigate its behavior and to assess its effect on freezing. © 2017 American Institute of Chemical Engineers AIChE J, 63: 200–208, 2018 相似文献