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Tsuchiyama, Ayako, Taka’aki Taira, Junichi Nakajima, and Roland Bürgmann. "Emergence of Low-Frequency Aftershocks of the 2019 Ridgecrest Earthquake Sequence." Bulletin of the Seismological Society of America 112, no. 2 (January 4, 2022): 750–62. http://dx.doi.org/10.1785/0120210206.
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ABSTRACT Low-frequency earthquakes (LFEs) generally have relatively stronger spectral components in the lower frequency range compared with what is expected for regular earthquakes based on their magnitude. LFEs generally occur in volcanic systems or deep (>∼15 km) in plate boundary fault zones; however, LFEs have also been observed in nonvolcanic, upper crustal settings. Because there are few studies that explore the spatiotemporal behaviors of LFEs in the shallow crust, it remains unclear whether the shallow-crustal LFEs reflect local attenuation in their immediate vicinity or differences in their source mechanism. Therefore, it is important to identify shallow-crustal LFEs and to characterize their spatiotemporal activity, which may also improve our understanding of LFEs. In this study, we focus on detecting shallow-crustal LFEs and explore the possible generation mechanisms. We analyze 29,646 aftershocks in the 2019 Ridgecrest, California, earthquake sequence, by measuring the frequency index (FI) to identify candidate low-frequency aftershocks (LFAs), while accounting for the magnitude dependency of the FI. Using small earthquakes (ML 1–3) recorded in the borehole stations to minimize the attenuation effects in near-surface layers, we identify 68 clear LFAs in total. Based on their distribution and comparisons with other seismic parameters measured by Trugman (2020), the LFAs possess distinct features from regular events in the same depths range, including low corner frequencies and low stress drops. Events in the close vicinity of LFAs exhibit lower average FI values than regular aftershocks, particularly if the hypocentral distance between an LFA and its neighbors is less than 1 km. Our results suggest that LFAs are related to local heterogeneity or a highly fractured fault zone correlated with an abundance of cross faults induced by the aftershock sequence at shallow depths. Zones of high pore-fluid pressure in intensely fractured fault zones could cause the bandlimited nature of LFAs and LFEs in general.
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Perju, Antonia, and Nongnoot Wongkaew. "Integrating high-performing electrochemical transducers in lateral flow assay." Analytical and Bioanalytical Chemistry 413, no. 22 (April 28, 2021): 5535–49. http://dx.doi.org/10.1007/s00216-021-03301-y.
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AbstractLateral flow assays (LFAs) are the best-performing and best-known point-of-care tests worldwide. Over the last decade, they have experienced an increasing interest by researchers towards improving their analytical performance while maintaining their robust assay platform. Commercially, visual and optical detection strategies dominate, but it is especially the research on integrating electrochemical (EC) approaches that may have a chance to significantly improve an LFA’s performance that is needed in order to detect analytes reliably at lower concentrations than currently possible. In fact, EC-LFAs offer advantages in terms of quantitative determination, low-cost, high sensitivity, and even simple, label-free strategies. Here, the various configurations of EC-LFAs published are summarized and critically evaluated. In short, most of them rely on applying conventional transducers, e.g., screen-printed electrode, to ensure reliability of the assay, and additional advances are afforded by the beneficial features of nanomaterials. It is predicted that these will be further implemented in EC-LFAs as high-performance transducers. Considering the low cost of point-of-care devices, it becomes even more important to also identify strategies that efficiently integrate nanomaterials into EC-LFAs in a high-throughput manner while maintaining their favorable analytical performance.
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Komatsu, Toshiya, Keisuke Hanaki, and Tomonori Matsuo. "Prevention of Lipid Inhibition in Anaerobic Processes by Introducing a Two-Phase System." Water Science and Technology 23, no. 7-9 (April 1, 1991): 1189–200. http://dx.doi.org/10.2166/wst.1991.0570.
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The inhibitory effect of lipids and prevention of this inhibition in a two-phase anaerobic process were examined using laboratory-scale reactors and batch experiments. Lipids were satisfactorily degraded in a two-phase anaerobic filter while in a single-phase system, inhibition resulted in poor lipid degradation. Unsaturated long-chain fatty acids (LFAs) had a greater inhibitory effect than saturated LFAs. Methane production as well as beta-oxidation (degradation of saturated LFAs) were inhibited by unsaturated LFAs. The saturation of unsaturated LFAs was not inhibited, and palmitate (C16:0) was accumulated in the degradation of oleate (C18:l) or linoleate (C18:2). Greater inhibition was observed at low pH values. Continuous operation of a suspended-growth acidogenic reactor showed that hydraulic retention times (HRTs) of no less than 8 hours were necessary to mitigate the inhibition in a two-phase process. The fact that saturation of oleate occurred at HRTs no less than 8 hours suggests that the saturation of unsaturated LFAs in an acidogenic reactor is essential in the prevention of lipid inhibition in two-phase anaerobic processes.
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MORGAN, SUSAN, DAVID J. W. HARDIE, and PATRICK C. MACEY. "A COMPARISON OF NUMERICAL METHODS FOR ACTIVE SONAR ARRAY PERFORMANCE." Journal of Computational Acoustics 09, no. 04 (December 2001): 1583–97. http://dx.doi.org/10.1142/s0218396x01001285.
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Low frequency active sonar (LFAS) arrays are complicated devices requiring careful design. Prototype LFAS arrays are expensive to construct and test. Accurate prediction of acoustic and electrical performance is therefore of great interest to LFAS designers. This generally involves solving a fully coupled problem relating the electrical drive to the resulting acoustic field. To derive results a numerical solution method is clearly the only recourse. This paper compares various numerical techniques in terms of accuracy, efficiency and overall applicability for the solution of LFAS problems. These are based around finite element (FE) and boundary element (BE) descriptions of the surrounding acoustic medium. Here we consider a pure FE approach based on wave envelope elements and a combined FE/BE scheme using an approximate BE formulation. These are contrasted with a pure BE approach that has been demonstrated to provide accurate predictions of LFAS array performance over a number of years. A piston stack transducer and a line array of free-flooding ring projectors are considered as example LFAS problems. The acoustic, structural and electrical responses are considered.
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Zhuang, Han, Chun Xu, Fang Gao, Yiwei Li, Chang Lei, and Chengzhong Yu. "Recent Advances in Silica-Nanomaterial-Assisted Lateral Flow Assay." Bioengineering 9, no. 7 (June 21, 2022): 266. http://dx.doi.org/10.3390/bioengineering9070266.
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Lateral flow assays (LFAs) have attracted much attention as rapid and affordable point-of-care devices for medical diagnostics. The global SARS-CoV-2 pandemic has further highlighted the importance of LFAs. Many efforts have been made to enhance the sensitivity of LFAs. In recent years, silica nanomaterials have been used to either amplify the signal of label materials or provide stability, resulting in better detection performance. In this review, the recent progress of silica-nanomaterial-assisted LFAs is summarized. The impact of the structure of silica nanomaterials on LFA performance, the challenges and prospects in this research area are also discussed.
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Zielony, Roman. "Lasy wybranych dużych obszarów leśnych = The forests in selected examples of Poland’s Large Forest Areas." Przegląd Geograficzny 93, no. 3 (2021): 463–83. http://dx.doi.org/10.7163/przg.2021.3.7.
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Key issues for spatial planning and development, nature protection and forestry in Poland relate to the problems encountered in determining the area of forests included within – and the boundaries of – what are known as the Large Forest Areas (LFAs) in Poland. Even as overall forest cover in the country has increased steadily – by about 2.5 million ha overall – since 1945, the data available for the LFAs relate to measurements made as long ago as in the 1960s and 1970s. Even then, it is often unclear whether it is total areas or areas of forest that are being referred to in relation to the LFAs. There is thus an urgent need for meas-urements to be updated, with a view to the present-day boundaries of the Areas being delim-ited. Some 80‑100 LFAs are in fact distinguished in Poland, in line with definitions relating to total area exceeding 10,000 ha (100 km2) and forest cover exceeding 35%. While many of the LFAs received Proper-Noun names at one point or another in their histories, as used locally in a given region, and in guides and publications, there are also less culturall-defined areas that still await naming. Efforts to determine the boundaries of the LFAs at this point allow, not only for renewed or de novo determination of their overall areas and areas of forest, but also for an advancement of our knowledge regarding any items of cultural heritage that may be present within LFAs. Such data will be useful or essential as new physiographic, economic and tourist guide-studies are developed; and they will encourage and facilitate the more-detailed analysis and assess-ment of forest management taking place within the limits of the LFAs. In line with the effort made to achieve the above goals, this article details selected problems encountered with the delimitation of forest boundaries and areas, as these are exemplified by the Polish LFAs of the Białowieża, Bolimów, Borki, Knyszyn, Kampinos, Noteć, Romincka, Tuchola, Łuków and Chojnów Forests. Figures for overall area and area of forest were indeed obtained and are presented here for the selected examples of LFAs, which are also augmented by the so-called Dobrzejewice and Lubniewice Forests not distinguished in this way before now.
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Garrod, Gala, Sophie I. Owen, J. Kenneth Baillie, Lisa Baldwin, Lottie Brown, Rachel L. Byrne, Ana I. Cubas-Atienzar, et al. "Comparative evaluation of ten lateral flow immunoassays to detect SARS-CoV-2 antibodies." Wellcome Open Research 6 (February 1, 2021): 18. http://dx.doi.org/10.12688/wellcomeopenres.16522.1.
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Background: Rapid mobilisation from industry and academia following the outbreak of the novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), led to the development and availability of SARS-CoV-2 lateral flow immunoassays (LFAs). High quality LFAs are urgently needed at the point of care to add to currently available diagnostic tools. In this study, we provide evaluation data for ten LFAs suitable for use at the point of care. Methods: COVID-19 positive patients (N=45), confirmed by reverse transcription – quantitative polymerase chain reaction (RT-qPCR), were recruited through the International Severe Acute Respiratory and Emerging Infection Consortium - Coronavirus Clinical Characterisation Consortium (ISARIC4C) study. Sera collected from patients with influenza A (N=20), tuberculosis (N=5), individuals with previous flavivirus exposure (N=21), and healthy sera (N=4), collected pre-pandemic, were used as negative controls. Ten LFAs manufactured or distributed by ASBT Holdings Ltd, Cellex, Fortress Diagnostics, Nantong Egens Biotechnology, Mologic, NG Biotech, Nal von Minden and Suzhou Herui BioMed Co. were evaluated. Results: Compared to RT-qPCR, sensitivity of LFAs ranged from 87.0-95.7%. Specificity against pre-pandemic controls ranged between 92.0-100%. Compared to IgG ELISA, sensitivity and specificity ranged between 90.5-100% and 93.2-100%, respectively. Percentage agreement between LFAs and IgG ELISA ranged from 89.6-92.7%. Inter-test agreement between LFAs and IgG ELISA ranged between kappa=0.792-0.854. Conclusions: LFAs may serve as a useful tool for rapid confirmation of ongoing or previous infection in conjunction with clinical suspicion of COVID-19 in patients attending hospital. Impartial validation prior to commercial sale provides users with data that can inform best use settings.
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Swanson, Christina, and Annalisa D'Andrea. "Lateral Flow Assay with Near-Infrared Dye for Multiplex Detection." Clinical Chemistry 59, no. 4 (April 1, 2013): 641–48. http://dx.doi.org/10.1373/clinchem.2012.200360.
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BACKGROUND Lateral flow assays (LFAs) are popular point-of-care diagnostic tools because they are rapid and easy to use. Nevertheless, they often lack analytical sensitivity and quantitative output and may be difficult to multiplex, limiting their usefulness in biomarker measurement. As a proof-of-concept study, we detail the design of a quantitative, multiplex LFA with readily available near-infrared (NIR) detection to improve analytical sensitivity. METHODS NIR dye was conjugated to selected antibodies and incorporated into LFAs. We used singleplex, optimized NIR-LFAs to measure interleukin (IL)-6 from 0 to 200 pg/mL and developed duplex assays to simultaneously measure IL-6 from 0 to 100 pg/mL (0 to 4.5 pmol/L) and C-reactive protein (CRP) from 50 to 2500 ng/mL (0.4 to 20 nmol/L) on a single test strip. Assays were tested on 60 different spiked samples and compared to ELISA results. RESULTS NIR-LFAs detected IL-6 in a 10% plasma matrix with a limit of detection of 4 pg/mL (182 fmol/L) and a CV <7%. Duplex NIR-LFAs quantitatively measured IL-6 and CRP concentrations simultaneously. Values strongly correlated to ELISA measurements, with R2 values of 0.9825 and 0.9711 for IL-6 and CRP, respectively. CONCLUSIONS NIR-LFAs exhibit quantitative measurement at pg/mL concentrations owing to a high signal-to-BACKGROUND ratio and robust detection antibody clearance through the test strip. Moreover, NIR-LFAs are able to detect molecules present at vastly different concentrations in multiplex format and compare favorably to ELISAs. LFAs with direct NIR detection may be a valuable tool for biomarker evaluation in the point-of-care setting.
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Friggens, N. C., T. H. McClelland, I. Kyriazakis, and M. Shanks. "An Assessment of Growth Potential in Small Sized British Sheep Breeds." Proceedings of the British Society of Animal Production (1972) 1993 (March 1993): 108. http://dx.doi.org/10.1017/s030822960002434x.
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Lamb producers in the Less Favoured Areas (LFAs) of the European Community appear, for different reasons, to be constrained by the economic value of the indigenous small-sized sheep breeds. The trial reported here forms part of a collaborative project whose overall aim is to improve the quality and marketability of sheep meat produced in the LFAs. The objective of this trial was to assess the growth potential of nine small sized sheep breeds, across three centres, providing a basis for subsequent production work. The three collaborating centres in Greece (paper no. 112), Spain (paper no. 26) and Scotland used indigenous breeds appropriate to their LFAs. The three British breeds studied were Scottish Blackface (SB), Welsh Mountain (WM), and Shetland (SH).
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Zhou, Zijie, Anouk van Hooij, Richard Vervenne, Claudia C. Sombroek, Elisa M. Tjon Kon Fat, Tom H. M. Ottenhoff, Paul L. A. M. Corstjens, Frank Verreck, and Annemieke Geluk. "Quantitative Rapid Test for Detection and Monitoring of Active Pulmonary Tuberculosis in Nonhuman Primates." Biology 10, no. 12 (December 2, 2021): 1260. http://dx.doi.org/10.3390/biology10121260.
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Nonhuman primates (NHPs) are relevant models to study the pathogenesis of tuberculosis (TB) and evaluate the potential of TB therapies, but rapid tools allowing diagnosis of active pulmonary TB in NHPs are lacking. This study investigates whether low complexity lateral flow assays utilizing upconverting reporter particles (UCP-LFAs) developed for rapid detection of human serum proteins can be applied to detect and monitor active pulmonary TB in NHPs. UCP-LFAs were used to assess serum proteins levels and changes in relation to the MTB challenge dosage, lung pathology, treatment, and disease outcome in experimentally MTB-infected macaques. Serum levels of SAA1, IP-10, and IL-6 showed a significant increase after MTB infection in rhesus macaques and correlated with disease severity as determined by pathology scoring. Moreover, these biomarkers could sensitively detect the reduction of bacterial levels in the lungs of macaques due to BCG vaccination or drug treatment. Quantitative measurements by rapid UCP-LFAs specific for SAA1, IP-10, and IL-6 in serum can be utilized to detect active progressive pulmonary TB in macaques. The UCP-LFAs thus offer a low-cost, convenient, and minimally invasive diagnostic tool that can be applied in studies on TB vaccine and drug development involving macaques.
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Gasperino, David, Ted Baughman, Helen V. Hsieh, David Bell, and Bernhard H. Weigl. "Improving Lateral Flow Assay Performance Using Computational Modeling." Annual Review of Analytical Chemistry 11, no. 1 (June 12, 2018): 219–44. http://dx.doi.org/10.1146/annurev-anchem-061417-125737.
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The performance, field utility, and low cost of lateral flow assays (LFAs) have driven a tremendous shift in global health care practices by enabling diagnostic testing in previously unserved settings. This success has motivated the continued improvement of LFAs through increasingly sophisticated materials and reagents. However, our mechanistic understanding of the underlying processes that drive the informed design of these systems has not received commensurate attention. Here, we review the principles underpinning LFAs and the historical evolution of theory to predict their performance. As this theory is integrated into computational models and becomes testable, the criteria for quantifying performance and validating predictive power are critical. The integration of computational design with LFA development offers a promising and coherent framework to choose from an increasing number of novel materials, techniques, and reagents to deliver the low-cost, high-fidelity assays of the future.
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Lubenko, Anatole. "Low-Frequency Antigens (LFAs)." Immunohematology 9, no. 2 (2020): 56–58. http://dx.doi.org/10.21307/immunohematology-2019-959a.
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Limon, Francisco, Angela L. Lamson, Jennifer L. Hodgson, Mark C. Bowler, and Sy A. Saeed. "Improving Detection of Depression Symptoms in Latino Farmworkers: Latino Farmworker Affective Scale." Hispanic Journal of Behavioral Sciences 41, no. 2 (February 27, 2019): 250–66. http://dx.doi.org/10.1177/0739986319831678.
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Latino farmworkers (LFWs) experience depression at a significant higher rate than non-Latino Whites; yet, research regarding depression-screening instruments in Spanish is scarce. The first author created a depression screener using terms used by LFWs to describe symptoms of depression. This study evaluated the effectiveness of the Latino Farmworker Affective Scale (LFAS-15) in accurately detecting symptoms of depression in this population as compared with the Patient Health Questionnaire (PHQ-9), the Brief Symptom Inventory (BSI-18), and the Center for Epidemiologic Studies Depression Scale (CESD-10) using the DSM structured clinical interview (SCID) as the reference standard. Study results indicated that the LFAS-15, as well as the PHQ-9, and the BSI-18 performed. The data also indicated that the LFAS-15 has good internal consistency, measures primarily one construct (depression), demonstrated convergent validity with the SCID, and has good combined sensitivity and specificity. Recommendations for clinical practice, policy, and research are offered.
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de Assis, Tália Santana Machado, Mariana Lourenço Freire, Janaína de Pina Carvalho, Ana Rabello, and Gláucia Cota. "Cost-effectiveness of anti-SARS-CoV-2 antibody diagnostic tests in Brazil." PLOS ONE 17, no. 2 (February 25, 2022): e0264159. http://dx.doi.org/10.1371/journal.pone.0264159.
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Background Although serologic tests for COVID-19 diagnosis are rarely indicated nowadays, they remain commercially available and widely used in Brazil. The objective of this study was to evaluate the cost-effectiveness of anti-SARS-CoV-2antibody diagnostic tests for COVID-19 in Brazil. Methods Eleven commercially available diagnostic tests, comprising five lateral-flow immunochromatographic assays (LFAs) and six immunoenzymatic assays (ELISA) were analyzed from the perspective of the Brazilian Unified Health System. Results The direct costs of LFAs ranged from US$ 11.42 to US$ 17.41and of ELISAs, from US$ 6.59 to US$ 10.31. Considering an estimated disease prevalence between 5% and 10%, the anti-SARS-CoV-2 ELISA (IgG) was the most cost-effective test, followed by the rapid One Step COVID-19 Test, at an incremental cost-effectiveness ratio of US$ 2.52 and US$ 1.26 per properly diagnosed case, respectively. Considering only the LFAs, at the same prevalence estimates, two tests, the COVID-19 IgG/IgM and the One Step COVID-19 Test, showed high effectiveness at similar costs. For situations where the estimated probability of disease is 50%, the LFAs are more costly and less effective alternatives. Conclusions Nowadays there are few indications for the use of serologic tests in the diagnosis of COVID-19 and numerous commercially available tests, with marked differences are observed among them. In general, LFA tests are more cost-effective for estimated low-COVID-19-prevalences, while ELISAs are more cost-effective for high-pretest-probability scenarios.
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Rudow, K. "Less favoured area payments – impacts on the environment, a German perspective." Agricultural Economics (Zemědělská ekonomika) 60, No. 6 (June 24, 2014): 260–72. http://dx.doi.org/10.17221/74/2013-agricecon.
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In the European Union, the support of Less Favoured Areas (LFA) has a long tradition as a part of the Common Agricultural Policy (CAP). Above all, it is the objective of the subsidies to maintain the agricultural production in LFAs, but also to consider the environmental aspects in LFAs and its funding schemes. Investigations of the latter are subject of this article. After having discussed the theoretical possibilities to influence environmental impacts by the funding scheme, several analyses are compiled and complemented by own calculations. The research has shown that agricultural practices within Less Favoured Areas are more environmentally friendly than in other areas. Environmentally friendly in this regard means e.g. a lower use of fertilisers and pesticides, but also a higher participation rate in agri-environmental measures. In addition, the crop structures of farms are analysed, e.g. the share of maize and wheat in farms inside and outside the LFAs. While the results presented in this paper relate mainly to Germany, the information on the European level is also taken into consideration. Finally, based on these investigations, recommendations for the revision of the funding programmes following 2013 are given.
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Liu, Zhi, Xiaocong He, Ang Li, Zhiguo Qu, and Feng Xu. "A two-dimensional mathematical model for analyzing the effects of capture probe properties on the performance of lateral flow assays." Analyst 144, no. 18 (2019): 5394–403. http://dx.doi.org/10.1039/c9an00669a.
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GELAN, A., and G. SCHWARZ. "The effect of single farm payments on less favoured areas agriculture in Scotland: a CGE analysis." Agricultural and Food Science 17, no. 1 (December 4, 2008): 3. http://dx.doi.org/10.2137/145960608784182317.
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This study quantifies impacts of common agricultural policy reform on farming in Less Favoured Areas (LFAs) in Scotland. LFAs are characterised by low agricultural productivity, because of unfavourable natural conditions, which allow only extensive farming systems such as cattle and sheep rearing. The differential impacts of the single farm payment on LFA farming is examined using a CGE modeling framework that accounts for inter-sectoral linkage effects. The simulation results indicate that the policy reform has considerably larger adverse effects on LFA farms than non-LFA farms and emphasize the need to consider spatially differential impacts in further adjustments to policy reforms taking into account local circumstances.;
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Li, Zedong, Shuang Wu, Jingcheng Ji, Yuemeng Bai, Pengpeng Jia, Yan Gong, Shangsheng Feng, and Fei Li. "Ball pen writing-without-ink: a truly simple and accessible method for sensitivity enhancement in lateral flow assays." RSC Advances 12, no. 4 (2022): 2068–73. http://dx.doi.org/10.1039/d1ra07684a.
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Frohnmeyer, Esther, Nadine Tuschel, Tobias Sitz, Cornelia Hermann, Gregor T. Dahl, Florian Schulz, Antje J. Baeumner, and Markus Fischer. "Aptamer lateral flow assays for rapid and sensitive detection of cholera toxin." Analyst 144, no. 5 (2019): 1840–49. http://dx.doi.org/10.1039/c8an01616j.
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Weiß, Lennart Jakob Konstantin, Georg Lubins, Emir Music, Philipp Rinklin, Hu Peng, Korkut Terkan, Dirk Mayer, and Bernhard Wolfrum. "(Digital Presentation) Stochastic Impact Electrochemistry in a Lateral-Flow Sensor Architecture." ECS Meeting Abstracts MA2022-01, no. 50 (July 7, 2022): 2116. http://dx.doi.org/10.1149/ma2022-01502116mtgabs.
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During the recent SARS-CoV-2 pandemic, lateral flow assays (LFAs) have written an indescribable story of success, as they provide means for decentralized, low-cost, and easy-to-use testing. However, LFAs in their most common form support only qualitative results and their sensitivity and limit of detection is significantly limited by the colorimetric readout method. In contrast, single-impact electrochemistry offers the possibility to quantify species beyond picomolar concentrations by recording individual species collisions with a biased microelectrode. Within this work, we investigate the integration of stochastic sensing into a LFA-architecture by combining a wax-patterned microchannel with a microelectrode array in order to detect silver nanoparticles by their oxidative dissolution. Here, we demonstrate the possibility to resolve individual nanoparticle collisions in a paper-based microchannel using a simplified reference-on-chip setup. Furthermore, we simulated a lateral-flow sensor, by flushing previously dried silver nanoparticles towards the electrode array, where the particles are subsequently detected. This proof-of-principle illustrates that single-impact electrochemistry might be a promising technique to extend the capability of LFAs. Especially, the integration of functionalized nanoparticle labels could enable the rapid and on-site detection of very dilute species with exceptional sensitivity.
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Papanikolopoulou, Vasiliki, Sotiria Vouraki, Stergios Priskas, Alexandros Theodoridis, Socratis Dimitriou, and Georgios Arsenos. "Economic Performance of Dairy Sheep Farms in Less-Favoured Areas of Greece: A Comparative Analysis Based on Flock Size and Farming System." Sustainability 15, no. 2 (January 15, 2023): 1681. http://dx.doi.org/10.3390/su15021681.
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Dairy sheep farming is a significant agricultural sector in Mediterranean countries, providing income and employment opportunities in less-favoured areas (LFAs). The economic performance of dairy sheep farms is of significant interest to LFAs. However, relevant literature is scarce. The objectives here were to evaluate the economic performance of dairy sheep farms in LFAs of Greece and perform a comparative analysis based on flock size and farming system. In total, 19 and 26 dairy sheep farms for two production periods were used. Farm technical (flock size, production, grazing and nutritional management) and economic (income and variable costs) data were collected. The economic performance of farms was estimated using Happy Goats, a decision support tool for small ruminant farming. Estimated economic parameters were analysed by flock size (≤150 ewes vs. >150 ewes) and farming system (intensive/semi-intensive vs. semi-extensive). Results showed that 37% and 31% of farms were operating with losses in each production period, respectively. Based on nutritional management, ewes produced about 50 kg less milk per milking period. Smaller and semi-extensive farms had significantly (p < 0.05) lower incomes and variable costs. A significantly (p < 0.05) lower average gross margin was reported for smaller compared to larger farms. Results suggest a better economic perspective for larger flock sizes.
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Koczula, Katarzyna M., and Andrea Gallotta. "Lateral flow assays." Essays in Biochemistry 60, no. 1 (June 30, 2016): 111–20. http://dx.doi.org/10.1042/ebc20150012.
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Lateral flow assays (LFAs) are the technology behind low-cost, simple, rapid and portable detection devices popular in biomedicine, agriculture, food and environmental sciences. This review presents an overview of the principle of the method and the critical components of the assay, focusing on lateral flow immunoassays. This type of assay has recently attracted considerable interest because of its potential to provide instantaneous diagnosis directly to patients. The range and interpretation of results and parameters used for evaluation of the assay will also be discussed. The main advantages and disadvantages of LFAs will be summarized and relevant future improvements to testing devices and strategies will be proposed. Finally, the major recent advances and future diagnostic applications in the LFA field will be explored.
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Luo, Hongzhi, Shan Liu, Lina Shi, Zhu Li, Qianwen Bai, Xiaoxin Du, Lijun Wang, He Zha, and Chenzhong Li. "Paper-Based Fluidic Sensing Platforms for β-Adrenergic Agonist Residue Point-of-Care Testing." Biosensors 12, no. 7 (July 12, 2022): 518. http://dx.doi.org/10.3390/bios12070518.
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The illegal use of β-adrenergic agonists during livestock growth poses a threat to public health; the long-term intake of this medication can cause serious physiological side effects and even death. Therefore, rapid detection methods for β-adrenergic agonist residues on-site are required. Traditional detection methods such as liquid chromatography have limitations in terms of expensive instruments and complex operations. In contrast, paper methods are low cost, ubiquitous, and portable, which has led to them becoming the preferred detection method in recent years. Various paper-based fluidic devices have been developed to detect β-adrenergic agonist residues, including lateral flow immunoassays (LFAs) and microfluidic paper-based analytical devices (μPADs). In this review, the application of LFAs for the detection of β-agonists is summarized comprehensively, focusing on the latest advances in novel labeling and detection strategies. The use of μPADs as an analytical platform has attracted interest over the past decade due to their unique advantages and application for detecting β-adrenergic agonists, which are introduced here. Vertical flow immunoassays are also discussed for their shorter assay time and stronger multiplexing capabilities compared with LFAs. Furthermore, the development direction and prospects for the commercialization of paper-based devices are considered, shedding light on the development of point-of-care testing devices for β-adrenergic agonist residue detection.
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Han, Gyeo-Re, and Min-Gon Kim. "Highly Sensitive Chemiluminescence-Based Lateral Flow Immunoassay for Cardiac Troponin I Detection in Human Serum." Sensors 20, no. 9 (May 2, 2020): 2593. http://dx.doi.org/10.3390/s20092593.
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Lateral flow assays (LFAs) have become the most common biosensing platforms for point-of-care testing due to their compliance with the ASSURED (affordable, sensitive, specific, user-friendly, rapid/robust, equipment-free, and deliverable to end-users) guidelines stipulated by the World Health Organization. However, the limited analytical sensitivity and low quantitative capability of conventional LFAs, which use gold nanoparticles (AuNPs) for colorimetric labeling, have prevented high-performance testing. Here, we report the development of a highly sensitive chemiluminescence (CL)-based LFA involving AuNPs conjugated with aldehyde-activated peroxidase and antibody molecules—i.e., AuNP-(ald)HRP-Ab—as a new conjugation scheme for high-performance testing in LFAs. When paired with the CL-based signal readout modality, the AuNP-(ald)HRP-Ab conjugate resulted in 110-fold enhanced sensitivity over the colorimetric response of a typical AuNP-Ab conjugate. To evaluate the performance of the CL-based LFA, we tested it with human cardiac troponin I (cTnI; a standard cardiac biomarker used to diagnose myocardial infarction) in standard and clinical serum samples. Testing the standard samples revealed a detection limit of 5.6 pg·mL−1 and acceptably reliable precision (with a coefficient of variation of 2.3%–8.4%), according to clinical guidelines. Moreover, testing the clinical samples revealed a high correlation (r = 0.97) with standard biochemical analyzers, demonstrating the potential clinical utility of the CL-based LFA for high-performance cTnI testing.
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Schouten, Marleen, Aris Gaaff, and Wim Heijman. "Less favoured area measure in the Netherlands: a welcome or negligible addition?" Applied Studies in Agribusiness and Commerce 3, no. 1-2 (May 30, 2009): 23–28. http://dx.doi.org/10.19041/apstract/2009/1-2/2.
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The Less Favoured Areas (LFAs) Directive (75/268) which was introduced in 1975, was the first common European instrument of regional agricultural structural policy. LFAs are areas where agriculture is hampered by permanent natural handicaps. The major objectives were to ensure the continuation of farming, thereby maintaining a minimum population level and preserving scenic landscapes and environmentally valuable habitats. In the Netherlands, the LFA measure is used as an additional payment, to compensate farmers for negative economic effects due to the conservation of these natural handicaps. It was not implemented as a stand alone policy, but is linked to measures aiming at active nature and landscape conservation management. In this paper, the effects will be examined of the regulations aiming at the conservation of natural handicaps on farm businesses within LFAs, when comparing them to farm businesses outside LFAs, where these regulations and handicaps do not exist. The main data source that was used is the Farm Accountancy Data Network. Reference groups of farms were compiled with the use of the simple and multiple imputation approach in Stars (Statistics for Regional Studies). Both analyses were tested with the use of a parametric and a nonparametric test. When comparing the results of both analyses, it can be concluded that there is no evidence that there is a statistical difference in family farm income corrected for and not corrected for LFA payment between the LFA farm businesses and the reference groups. Based on these findings it can be concluded that the size of the compensatory allowances is small and there is no evidence that it has a significant effect on the family farm income of LFA farm businesses. The main purpose of the Dutch LFA policy is to compensate farm businesses for negative economic effects due to the conservation of natural handicaps. Although this may be true for some individual farms, based on the methods used in this paper, it appears not to be the case for the collectivity of LFA premium beneficiaries as a whole.
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G. V. Podporkin, E. S. Kalakutsky, V.E. Pilshikov, and A. D. Sivaev. "Lightning Protection of Electric Power Overhead Distribution Lines by Long-Flashover Arresters in Russia." Journal of Energy - Energija 60, no. 1-4 (August 22, 2022): 101–9. http://dx.doi.org/10.37798/2011601-4269.
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A simple and effective method for lightning protection of power overhead distribution lines by long flashover arresters (LFAs) is presented. Even large lightning currents do not pose any threat to these arresters because the discharge develops in the air and not inside the device. LFAs, which are based on the creeping discharge effect, increase the lightning flashover length significantly and thus eliminate Power Arc Follow (PAF). To protect a line against induced overvoltages, a single arrester should be mounted on a pole. To protect a line against direct lightning strokes, LFA-M arresters should be mounted in parallel with each insulator. For covered-conductor overhead lines (CCL) using conductors with three-layer insulation a new lightning protection approach is suggested, involving use of antenna-type long flashover arresters whose essential component is the protected conductor itself. The essence of antennatype long flashover arresters (LFA-A) is that the arrester which is connected to the antenna gets flashed over well before the lightning leader comes in immediate contact with the line. The toroid-shaped antenna made of a metal tube is mounted on the covered conductor’s surface midway between the protector’s edge and the piercing clamp with the help of the toroid fixation unit. As the lightning leader progresses from a thunderstorm cloud to the CCL a high potential gets induced on the LFA antenna. A voltage drop that develops between the electrode and the zero-potential conductor core gives rise to development of a creeping discharge. Even before the lightning leader hits the line the creeping discharge channel flashes over the covered conductor’s surface Thereby the conductor insulation get bypassed by the discharge channel and thus protected against puncture. LFA’s main applications and field experience are presented.
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Sun, Hsiao-Ling, Wei-Tao Peng, and Jeng-Da Chai. "Assessment of the LFAs-PBE exchange–correlation potential for high-order harmonic generation of aligned H2+ molecules." RSC Advances 6, no. 40 (2016): 33318–25. http://dx.doi.org/10.1039/c6ra03713e.
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We examine the performance of the LFAs-PBE exchange-correlation potential for the HHG spectra and related properties of H2+ molecules aligned parallel and perpendicular to the polarization of an intense linearly polarized laser pulse.
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Majdinasab, Marjan, Mihaela Badea, and Jean Louis Marty. "Aptamer-Based Lateral Flow Assays: Current Trends in Clinical Diagnostic Rapid Tests." Pharmaceuticals 15, no. 1 (January 13, 2022): 90. http://dx.doi.org/10.3390/ph15010090.
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The lateral flow assay (LFA) is an extensively used paper-based platform for the rapid and on-site detection of different analytes. The method is user-friendly with no need for sophisticated operation and only includes adding sample. Generally, antibodies are employed as the biorecognition elements in the LFA. However, antibodies possess several disadvantages including poor stability, high batch-to-batch variation, long development time, high price and need for ethical approval and cold chain. Because of these limitations, aptamers screened by an in vitro process can be a good alternative to antibodies as biorecognition molecules in the LFA. In recent years, aptamer-based LFAs have been investigated for the detection of different analytes in point-of-care diagnostics. In this review, we summarize the applications of aptamer technology in LFAs in clinical diagnostic rapid tests for the detection of biomarkers, microbial analytes, hormones and antibiotics. Performance, advantages and drawbacks of the developed assays are also discussed.
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Fischer, Peter U., Kerstin Fischer, Kurt C. Curtis, Yuefang Huang, Nicole Fetcho, Charles W. Goss, and Gary J. Weil. "Evaluation of Commercial Rapid Lateral Flow Tests, Alone or in Combination, for SARS-CoV-2 Antibody Testing." American Journal of Tropical Medicine and Hygiene 105, no. 2 (August 11, 2021): 378–86. http://dx.doi.org/10.4269/ajtmh.20-1390.
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ABSTRACT. Antibody tests can be tools for detecting current or past severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 [coronavirus disease 2019 (COVID-19)]) infections. Independent test evaluations are needed to document the performance with different sample sets. We evaluated six lateral flow assays (LFAs) and two laboratory-based tests (EUROIMMUN-SARS-CoV-2 ELISA and Abbott-Architect-SARS-CoV-2-IgG). We tested 210 plasma samples from 89 patients diagnosed with acute COVID-19. These samples were collected at different time points after the onset of symptoms. In addition, 80 convalescent plasma samples, and 168 pre-pandemic samples collected from adults in the United States and in Africa were tested. LFA performance varied widely, and some tests with high sensitivity had low specificity. LFA sensitivities were low (18.8–40.6%) for samples collected 0 to 3 days after symptom onset, and were greater (80.3–96.4%) for samples collected > 14 days after symptom onset. These results are similar to those obtained by ELISA (15.6% and 89.1%) and chemiluminescent microparticle assay (21.4% and 93.1%). The range of test specificity was between 82.7% and 97%. The combined use of two LFAs can increase specificity to more than 99% without a major loss of sensitivity. Because of suboptimal sensitivity with early COVID-19 samples and background reactivity with some pre-pandemic samples, none of the evaluated tests alone is reliable enough for definitive diagnosis of COVID-19 infection. However, antibody testing may be useful for assessing the status of the epidemic or vaccination campaign. Some of the LFAs had sensitivities and specificities that were comparable to those of more expensive laboratory tests, and these may be useful for seroprevalence surveys in resource-limited settings.
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Chen, M., and J. Chen. "Phosphorus release from agriculture to surface waters: past, present and future in China." Water Science and Technology 57, no. 9 (May 1, 2008): 1355–61. http://dx.doi.org/10.2166/wst.2008.256.
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So far, there is no clear picture at national level regarding the severity, spatial distribution, trend and driving forces of phosphorus (P) release from agriculture to surface waters in China, which presents a major obstacle for surface water quality management and relevant policy-making. By applying a proposed Activity-Unit-Balance (AUB) methodology, this paper retrospects and prospects phosphorus release from agricultural activities to surface waters from1978 to 2050 in China. Modelling results reveal that P load from agriculture has increased 3.4 times during 1978–2005 and will increase by 1.8 times during 2005–2050. Although major contribution factors are mineral fertiliser application (MFA) and livestock feeding activities (LFAs), LFAs will be the single largest source of increased total P load in the next decades. Most importantly, agricultural pollution in China is spatially overlapped with industrial and domestic pollution, and regions in the southeast to “Heihe-Tengchong” line have to be confronted with an austere challenge to control and manage industrial and domestic pollution as well as pollution from agriculture at present and in future.
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Grant, Benjamin D., Caitlin E. Anderson, Luis F. Alonzo, Spencer H. Garing, John R. Williford, Ted A. Baughman, Rafael Rivera, et al. "A SARS-CoV-2 coronavirus nucleocapsid protein antigen-detecting lateral flow assay." PLOS ONE 16, no. 11 (November 10, 2021): e0258819. http://dx.doi.org/10.1371/journal.pone.0258819.
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Inexpensive, simple, rapid diagnostics are necessary for efficient detection, treatment, and mitigation of COVID-19. Assays for SARS-CoV2 using reverse transcription polymerase chain reaction (RT-PCR) offer good sensitivity and excellent specificity, but are expensive, slowed by transport to centralized testing laboratories, and often unavailable. Antigen-based assays are inexpensive and can be rapidly mass-produced and deployed at point-of-care, with lateral flow assays (LFAs) being the most common format. While various manufacturers have produced commercially available SARS-Cov2 antigen LFAs, access to validated tests remains difficult or cost prohibitive in low-and middle-income countries. Herein, we present a visually read open-access LFA (OA-LFA) using commercially-available antibodies and materials for the detection of SARS-CoV-2. The LFA yielded a Limit of Detection (LOD) of 4 TCID50/swab of gamma irradiated SARS-CoV-2 virus, meeting the acceptable analytical sensitivity outlined by in World Health Organization target product profile. The open-source architecture presented in this manuscript provides a template for manufacturers around the globe to rapidly design a SARS-CoV2 antigen test.
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Sulewski, Piotr, and Adam Wąs. "Awareness of Sustainable Agriculture among Polish Farmers – Beneficiaries of the CAP." Wieś i Rolnictwo, no. 4 (181) (December 20, 2018): 43–65. http://dx.doi.org/10.53098/wir042018/03.
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The main objective of the study was an assessment of the awareness and actions undertaken by farmers in the selected fields of farm activity from the sustainability point of view. The research covered a representative sample of 600 farmers participating in the Polish Farm Accountancy Data Network (FADN). The data from the FADN database were supplied by the information from interviews with farmers. The sustainability indicators were analysed with regard to the amount and type of subsidies received. The sample was divided regarding type and amount of support. The results showed that, on average, the highest sustainability indicators were in farms receiving support under agri-environmental programmes and located in LFAs (less favoured areas), while the lowest were usually in other farms in the LFAs. The analysis of differences between farms categorised according to the total value of subsidies received, found that on average farms with the highest absolute level of support achieved higher sustainability parameters in all dimensions. Based on the results it can be concluded that higher and more varied subsidies to farmers are positively correlated with sustainability of their farms.
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Palombo, Maria Rita, Maria Teresa Alberdi, Luca Bellucci, and Raffaele Sardella. "An intriguing middle-sized horse from Coste San Giacomo (Anagni Basin, central Italy)." Quaternary Research 87, no. 2 (March 2017): 347–62. http://dx.doi.org/10.1017/qua.2017.6.
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AbstractVarious species and ecomorphotypes of the genus Equus are recorded in several southern European Early Pleistocene local faunal assemblages (LFAs), though their taxonomy, phylogenetic relationships, and chronological distribution are still a matter of debate. This article aims to increase knowledge on the European pre-Olduvai stenonoid horses by describing and discussing the equid sample from the middle Villafranchian (Gelasian) Italian site of Coste San Giacomo (CSG; Anagni). Although horse remains from CSG are scanty, the morphological traits, dimensions, and proportions of teeth and some limb bones suggest some affinities with middle-sized European stenonoid horses, in particular with Equus senezensis, as supported by statistical analysis. This opens a new window on the possible phylogenetic relationships of the middle-sized, slender middle Villafranchian horses, although some questions about their actual taxonomic rank cannot be firmly answered based on available data. The complex relationship among environment, structure of the accompanying mammalian fauna, and the presence in the Early Pleistocene LFAs of only one equid, large or middle-sized, or even of more horse species with different size is briefly discussed.
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Bikkarolla, Santosh Kumar, Sara E. McNamee, Paul Vance, and James McLaughlin. "High-Sensitive Detection and Quantitative Analysis of Thyroid-Stimulating Hormone Using Gold-Nanoshell-Based Lateral Flow Immunoassay Device." Biosensors 12, no. 3 (March 19, 2022): 182. http://dx.doi.org/10.3390/bios12030182.
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Au nanoparticles (AuNPs) have been used as signal reporters in colorimetric lateral flow immunoassays (LFAs) for decades. However, it remains a major challenge to significantly improve the detection sensitivity of traditional LFAs due to the low brightness of AuNPs. As an alternative approach, we overcome this problem by utilizing 150 nm gold nanoshells (AuNSs) that were engineered by coating low-density silica nanoparticles with a thin layer of gold. AuNSs are dark green, have 14 times larger surface area, and are approximately 35 times brighter compared to AuNPs. In this study, we used detection of thyroid-stimulating hormone (TSH) in a proof-of-concept assay. The limit of detection (LOD) with AuNS-based LFA was 0.16 µIU/mL, which is 26 times more sensitive than the conventional colorimetric LFA that utilizes AuNP as a label. The dynamic range of the calibration curve was 0.16–9.5 µIU/mL, making it possible to diagnose both hyperthyroidism (<0.5 µIU/mL) and hypothyroidism (>5 µIU/mL) using AuNS-based LFA. Thus, the developed device has a strong potential for early screening and diagnosis of diseases related to the thyroid hormone.
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Prišenk, Jernej, and Jernej Turk. "Assessment of Concept between Rural Development Challenges and Local Food Systems: A Combination between Multi-Criteria Decision Analysis and Econometric Modelling Approach." Sustainability 14, no. 6 (March 16, 2022): 3477. http://dx.doi.org/10.3390/su14063477.
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This study investigates the influence of social, economic, and environmental impacts on the promotion and marketing systems of local food products from mountain areas in Slovenia. These impacts were assessed using an econometric modelling approach. Two econometric models were developed (one for production and one for marketing). The case studies of local food products were selected from Slovenian mountain regions, most of which were from less-favored areas (LFAs). A majority of the selected food commodities were of high quality, with or without protected designations. Data collection was carried out via interviews. Due to production limitation on mountain areas in Slovenia and other constraints in LFAs, the socio-economic and environmental impacts on success of production and marketing systems need to be clarified. These relations present a potential impact on the wider socio-economic development in the region. The empirical results, obtained using an econometric modelling approach, clearly show the importance of encouraging the socio-economic and environmental impacts in ensuring the marketing and production potentials of local food products. The result express good relationships, and cooperation between the actors in the food supply chains contributing to a successful marketing system and production system of local food products (small, average, large) is dependent on the available local labour in mountain rural areas.
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Ardekani, Leila Safaee, and Peter Waaben Thulstrup. "Gold Nanoparticle-Mediated Lateral Flow Assays for Detection of Host Antibodies and COVID-19 Proteins." Nanomaterials 12, no. 9 (April 25, 2022): 1456. http://dx.doi.org/10.3390/nano12091456.
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Coronaviruses, that are now well-known to the public, include a family of viruses that can cause severe acute respiratory syndrome (SARS) and other respiratory diseases, such as Middle East respiratory syndrome (MERS). Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the seventh member of this coronavirus family, was detected in 2019 and can cause a number of respiratory symptoms, from dry cough and fever to fatal viral pneumonia. Various diagnostic assays ranging from real-time polymerase chain reaction (RT-PCR) to point-of-care medical diagnostic systems have been developed for detection of viral components or antibodies targeting the virus. Point-of-care assays allow rapid diagnostic assessment of infectious patients. Such assays are ideally simple, low-cost, portable tests with the possibility for on-site field detection that do not require skilled staff, sophisticated equipment, or sample pretreatment, as compared to RT-PCR. Since early 2021 when new SARS-CoV-2 variants of concern increased, rapid tests became more crucial in the disease management cycle. Among rapid tests, gold nanoparticle (GNP)-based lateral flow assays (LFAs) have high capacity for performing at the bedside, paving the way to easy access to diagnosis results. In this review, GNP-based LFAs used for either COVID-19 proteins or human response antibodies are summarized and recommendations for their improvement have been suggested.
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Ardekani, Leila Safaee, and Peter Waaben Thulstrup. "Gold Nanoparticle-Mediated Lateral Flow Assays for Detection of Host Antibodies and COVID-19 Proteins." Nanomaterials 12, no. 9 (April 25, 2022): 1456. http://dx.doi.org/10.3390/nano12091456.
Full textAbstract:
Coronaviruses, that are now well-known to the public, include a family of viruses that can cause severe acute respiratory syndrome (SARS) and other respiratory diseases, such as Middle East respiratory syndrome (MERS). Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the seventh member of this coronavirus family, was detected in 2019 and can cause a number of respiratory symptoms, from dry cough and fever to fatal viral pneumonia. Various diagnostic assays ranging from real-time polymerase chain reaction (RT-PCR) to point-of-care medical diagnostic systems have been developed for detection of viral components or antibodies targeting the virus. Point-of-care assays allow rapid diagnostic assessment of infectious patients. Such assays are ideally simple, low-cost, portable tests with the possibility for on-site field detection that do not require skilled staff, sophisticated equipment, or sample pretreatment, as compared to RT-PCR. Since early 2021 when new SARS-CoV-2 variants of concern increased, rapid tests became more crucial in the disease management cycle. Among rapid tests, gold nanoparticle (GNP)-based lateral flow assays (LFAs) have high capacity for performing at the bedside, paving the way to easy access to diagnosis results. In this review, GNP-based LFAs used for either COVID-19 proteins or human response antibodies are summarized and recommendations for their improvement have been suggested.
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Sivle, Lise Doksæter, Petter Helgevold Kvadsheim, Michael A. Ainslie, Andrew Solow, Nils Olav Handegard, Nina Nordlund, and Frans-Peter A. Lam. "Impact of naval sonar signals on Atlantic herring (Clupea harengus) during summer feeding." ICES Journal of Marine Science 69, no. 6 (May 14, 2012): 1078–85. http://dx.doi.org/10.1093/icesjms/fss080.
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Abstract Sivle, L. D., Kvadsheim, P. H., Ainslie, M. A., Solow, A., Handegard, N. O. Nordlund, N., and Lam, F-P. A. 2012. Impact of naval sonar signals on Atlantic herring (Clupea harengus) during summer feeding. – ICES Journal of Marine Science, 69: 1078–1085. Naval anti-submarine sonars produce intense sounds within the hearing range of Atlantic herring (Clupea harengus). In this study, schools of Atlantic herring were exposed to sonar signals of 1–2 kHz (low-frequency active sonar, LFAS) and 6–7 kHz (mid-frequency active sonar, MFAS) and playbacks of killer whale feeding sounds during their summer feeding migration in the Norwegian Sea. The fish schools neither significantly dived nor changed their packing density in response to the LFAS and MFAS transmissions received by the fish at estimated sound pressure levels (SPLs; RMS) up to 176 and 157 dB re 1 μPa and estimated cumulative sound exposure levels up to 181 and 162 dB re 1 μPa² s, respectively. In contrast, killer whale feeding sounds induced diving responses at received SPLs at ∼150 dB re 1 μPa. Herring behaviour was studied by using a 116-kHz hull mounted fishery sonar. This seems a promising method for studying the behaviour of free-ranging fish in situations in which other methods are difficult to use, such as migrating schools and fish close to the surface.
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Senda, Masayuki. "Restructuring of chestnut cultivation adopting grazing and I.T. in LFAs." Agricultural Information Research 13, no. 4 (2004): 331–46. http://dx.doi.org/10.3173/air.13.331.
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Patil, Ranjana A., and Sangesh P. Zodape. "X-Ray Diffraction and SEM Investigation of Solidification/ Stabilization of Nickel and Chromium Using Fly ash." E-Journal of Chemistry 8, s1 (2011): S395—S403. http://dx.doi.org/10.1155/2011/274275.
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The main thrust of the paper is mechanism of immobilization of nickel(Ni) and chromium(Cr) metal sludge by solidification/stabilization using lime fly ash and sand (LFAS). The mineralogy of fly ash used for the study has been determined on the basis of x- ray diffraction analysis (XRD). Attempts have been made to investigate the consequences of interaction of heavy metal ion with constituents of lime fly ash sand composite on the basis of XRD studies and scanning electron microscopy (SEM, except chromium).
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Vilkhivskaya, O. V., I. A. Evdokimov, V. V. Likhanskii, and E. Yu Afanasieva. "RECENT VALIDATION STUDY OF THE TECHNIQUE FOR EXPRESS EVALUATION OF BURNUP IN LEAKING FUEL ASSEMBLIES OF WWER POWER UNITS." EPJ Web of Conferences 247 (2021): 10013. http://dx.doi.org/10.1051/epjconf/202124710013.
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The present work continues the series of papers on the revision of the conventional technique for evaluation of leaking fuel burnup during reactor operation at nuclear power plants (NPPs). The focus was made on reduction of uncertainties in evaluation of leaking fuel burnup in modern fuel cycles at WWER-1000 power units. A set of models was proposed for express calculation of the build-up of caesium isotopes in fuel and to relate 134Cs/137Cs activity ratio with fuel burnup for each rod in the core. These models are based on routine neutronic calculations of pin-by-pin linear heat generation rates which are performed at NPPs for each particular fuel cycle with particular core loading pattern (however, these calculations do not provide data on caesium inventory in fuel). Previously, the proposed models have been validated against several practical cases. This latest validation study relied on the analysis of the most recent fuel cycles at two NPPs that reported spike-events and identified the leaking fuel assemblies (LFAs) after the reactor shutdown. The calculated 134Cs/137Cs activity ratios in the fuel of the LFAs were compared to the NPPs data on the activity measurements, and to the post-irradiation examination (PIE) data provided for one FA. A reasonable agreement between the model predictions and the experimental data on 134Cs/137Cs activity ratios in the fuel as a function of its burnup is shown for the advanced FA designs in modern fuel cycles.
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Anderson, Caitlin E., Toan Huynh, David J. Gasperino, Luis F. Alonzo, Jason L. Cantera, Stephen P. Harston, Helen V. Hsieh, et al. "Automated liquid handling robot for rapid lateral flow assay development." Analytical and Bioanalytical Chemistry 414, no. 8 (January 29, 2022): 2607–18. http://dx.doi.org/10.1007/s00216-022-03897-9.
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AbstractThe lateral flow assay (LFA) is one of the most popular technologies on the point-of-care diagnostics market due to its low cost and ease of use, with applications ranging from pregnancy to environmental toxins to infectious disease. While the use of these tests is relatively straightforward, significant development time and effort are required to create tests that are both sensitive and specific. Workflows to guide the LFA development process exist but moving from target selection to an LFA that is ready for field testing can be labor intensive, resource heavy, and time consuming. To reduce the cost and the duration of the LFA development process, we introduce a novel development platform centered on the flexibility, speed, and throughput of an automated robotic liquid handling system. The system comprises LFA-specific hardware and software that enable large optimization experiments with discrete and continuous variables such as antibody pair selection or reagent concentration. Initial validation of the platform was demonstrated during development of a malaria LFA but was readily expanded to encompass development of SARS-CoV-2 and Mycobacterium tuberculosis LFAs. The validity of the platform, where optimization experiments are run directly on LFAs rather than in solution, was based on a direct comparison between the robotic system and a more traditional ELISA-like method. By minimizing hands-on time, maximizing experiment size, and enabling improved reproducibility, the robotic system improved the quality and quantity of LFA assay development efforts. Graphical abstract
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Kostopoulos, D. S., and G. D. Koufos. "SIMILARITY RELATIONSHIPS AMONG GREEK MIDDLE MIOCENE TO EARLY - MIDDLE PLEISTOCENE MAMMAL ASSEMBLAGES." Bulletin of the Geological Society of Greece 40, no. 1 (June 8, 2018): 134. http://dx.doi.org/10.12681/bgsg.16498.
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The Greek fossil record of small and large mammal Local Faunal Assemblages is studied and compared by means of cluster analysis techniques using Jaccard similarity index and unweighted pair-group method. The analysis allow recognizing a good arrangement of the Greek LFAs according to time and a main cluster gap, corresponding to an important faunal renewal that, however, is not synchronous in the large and small mammal community. Minor groupings of large mammal faunas seem also to fit with main climatic trends, whereas the small mammal assemblage appears to undergo longer periods oftaxonomic stability
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Kostylev, D. V., and N. V. Boginskaya. "Seismoacoustic observations using molecular-electronic hydrophones on Sakhalin and the South Kuril Islands (Kunashir Island)." Geosystems of Transition Zones 4, no. 4 (2020): 486–99. http://dx.doi.org/10.30730/gtrz.2020.4.4.486-499.
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The article presents the main characteristics and studies spectral and recording capabilities of experimental samples of three types of molecular-electronic hydrophones with different sizes of electrochemical converting cells, which were installed in the central part of the south of Sakhalin Island and on Kunashir Island (southern part of the Kuril ridge) at the end of 2018. A hydrophone on a new technological basis (with an increased sensor sensitivity relative to previously conducted studies) was approved on Kunashir Island. Equipment of this type was used for observations on the territory of the Sakhalin region for the first time. As a result of continuous seismoacoustic observations on Kunashir Island, in seven cases out of 35 studied (from May 1, 2019 to February 29, 2020) earthquakes, a low-frequency anticipatory signal (LFAS) was detected, and all seven events had a depth of hypocenter of more than 80 km. In the area of the Central Sakhalin fault, in addition to the possibility of registering the LFAS, spectral features in the recording of waveforms were studied for different conditions of instrument installation. It is shown that the influence of such atmospheric factor as wind load significantly affects hydrophones located in a shallow water body and a shallow open borehole. It is shown that the influence of such atmospheric factor as wind load significantly affects hydrophones located in a shallow water body and a shallow open borehole. However, molecular-electronic hydrophones have demonstrated the ability to fully record seismic events regardless of the installation conditions of the equipment.
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Zygoyiannisl, D., C. Stamatarisl, N. Katsaounis, N. Friggens, and G. Emmans. "The growth of three Greek dairy breeds of lamb to three slaughter weights as affected by different levels of nutrition." Proceedings of the British Society of Animal Production (1972) 1994 (March 1994): 198. http://dx.doi.org/10.1017/s0308229600027422.
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Lamb producers in the Less Favoured Areas (LFAs) of the European Community appear, for different reasons, to be constrained by the economic value of the indigenous small-sized sheep breeds. The trial reported here forms part of a collaborative project whose overall aim is to improve the quality and marketability of sheep meat produced in the LFAs. The objective of this trial was to measure the growth and body composition of entire male lambs of 3 Greek dairy breeds from early weaning to 3 slaughter weights chosen to be of potential commercial interest.In all 108 ram lambs were used with equal numbers from the 3 breeds: Karagouniko (K), Serres (S) and Boutsiko (B). The lambs were weaned at about 8 weeks of age onto one of 3 levels of concentrate allowance called H, M and L with ad libitum access to alfalfa hay. The concentrate contained 175 g crude protein and 11.0 MJ ME/kg as fed. The concentrate allowances were calculated on incremental time-based scales which were related to the ad libitum intake of each of the breeds as observed in a previous experiment. The highest allowance was intended to be at about 0.80 of the ad libitum intake previously seen. Allowance L was 1/3 and level M 2/3 of H. Lambs were housed in individual pens on sawdust. Liveweight and hay intake were recorded once per week; there were no overall refusals of concentrate between start and slaughter. Lambs were slaughtered at 23. 28 or 33 kg irrespective of breed and carcasses stored for compositional evaluation.
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Owen, Sophie I., Christopher T. Williams, Gala Garrod, Alice J. Fraser, Stefanie Menzies, Lisa Baldwin, Lottie Brown, et al. "Twelve lateral flow immunoassays (LFAs) to detect SARS-CoV-2 antibodies." Journal of Infection 84, no. 3 (March 2022): 355–60. http://dx.doi.org/10.1016/j.jinf.2021.12.007.
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Ormanoudis, Ch, and C. Panayiotou. "Applications of the LFAS model to 1-alkanol + n-alkane systems." Fluid Phase Equilibria 89, no. 1 (August 1993): 217–28. http://dx.doi.org/10.1016/0378-3812(93)85051-m.
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Bischof, John C., and Kenneth R. Diller. "From Nanowarming to Thermoregulation: New Multiscale Applications of Bioheat Transfer." Annual Review of Biomedical Engineering 20, no. 1 (June 4, 2018): 301–27. http://dx.doi.org/10.1146/annurev-bioeng-071516-044532.
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This review explores bioheat transfer applications at multiple scales from nanoparticle (NP) heating to whole-body thermoregulation. For instance, iron oxide nanoparticles are being used for nanowarming, which uniformly and quickly rewarms 50–80-mL (≤5-cm-diameter) vitrified systems by coupling with radio-frequency (RF) fields where standard convective warming fails. A modification of this approach can also be used to successfully rewarm cryopreserved fish embryos (∼0.8 mm diameter) by heating previously injected gold nanoparticles with millisecond pulsed laser irradiation where standard convective warming fails. Finally, laser-induced heating of gold nanoparticles can improve the sensitivity of lateral flow assays (LFAs) so that they are competitive with laboratory tests such as the enzyme-linked immunosorbent assay. This approach addresses the main weakness of LFAs, which are otherwise the cheapest, easiest, and fastest to use point-of-care diagnostic tests in the world. Body core temperature manipulation has now become possible through selective thermal stimulation (STS) approaches. For instance, simple and safe heating of selected areas of the skin surface can open arteriovenous anastomosis flow in glabrous skin when it is not already established, thereby creating a convenient and effective pathway to induce heat flow between the body core and environment. This has led to new applications of STS to increase or decrease core temperatures in humans and animals to assist in surgery (perioperative warming), to aid ischemic stress recovery (cooling), and even to enhance the quality of sleep. Together, these multiscale applications of nanoparticle heating and thermoregulation point to dramatic opportunities for translation and impact in these prophylactic, preservative, diagnostic, and therapeutic applications of bioheat transfer.
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Chisale, Master. "A comparative evaluation of three methods for the rapid diagnosis of cryptococcal meningitis (CM) among HIV-infected patients in Northern Malawi." Malawi Medical Journal 32, no. 1 (March 31, 2020): 3–7. http://dx.doi.org/10.4314/mmj.v32i1.2.
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IntroductionCryptococcal meningitis (CM) is the most common systemic fungal infection in patients with HIV infection. Rapid diagnosis and timely initiation of antifungal therapy are key to reducing mortality rate associated with CM. This study aims to evaluate the ability of four different diagnostic tests (Gram stain, India ink, and two types of commercial lateral flow assay [LFA]) to identify CM-positive patients and to compare the sensitivity and specificity of these tests.MethodsThis was a prospective cross-sectional study on diagnostic tests accuracy conducted in Northern Malawi. The target population was HIV-infected adult patients presenting with features of meningitis. Four types of diagnostic tests were conducted: India ink, Gram stain, and two types of commercial lateral flow assay (LFA) (Immy, Inc., OK, USA and Dynamiker Biotechnology (Tianjin) Co., Ltd), Singapore). Culture was conducted as the reference standard.ResultsA total of 265 samples were collected. The rate of positive CM detection ranged from 6.4% (using India ink) to 14.3% (using LFA). India ink exhibited the lowest sensitivity of 54.8% (95% confidence interval [CI]: 36.0%–72.7%), followed by Gram stain (61.3%; 95% CI: 42.2%–78.2%). The Dynamiker LFA exhibited the highest sensitivity of 100.0% (95% CI: 90.0%–100.0%) but a lower specificity (97.0%; 93.9%–98.8%) compared to the Immy LFA (98.3%; 95% CI: 95.7%–99.5%). ConclusionLFA diagnostic methods have the potential to double the detection rate of CM-positive patients in resource-limited countries such as Malawi. As such, LFAs should be considered to become the main diagnostic tests used for CM diagnostics in these countries. Our data indicate that LFAs may be the best method for diagnosing CM and exhibits the highest diagnostic accuracy as it has shown that it outperforms cell culture, the current gold standard.
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Lososová, Jana, Jaroslav Svoboda, and Radek Zdeněk. "Comparison of Operational Subsidies on Less Favoured Areas in EU Countries." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 64, no. 3 (2016): 979–92. http://dx.doi.org/10.11118/actaun201664030979.
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This article is aimed at an analysis of operational subsidies on the Less Favoured Areas (LFA) in the European Union countries. With the help of cluster analysis, the EU countries were divided into groups and, using correlation and regression analyses, the relations between defined indicators were evaluate. The indicators of FADN EU related to the cultivated land area were completed with relative indicators. Some differences were proved in subsidy effectiveness between particular groups of the countries. The amount of operational subsidies only has a positive impact on subsidised costs in the mountain LFAs. Worse productive and climate conditions increase the dependence of the output on subsidies related to cost effectiveness. No dependence of the output share of subsidies and the subsidised costs was proven in all groups.