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Kunikowska, Jolanta, Anna Zemczak, Monika Górska, Renata Matyskiel, Maciej Słodkowski, Izabela Łoń, Beata Chrapko, Beata Kos-Kudła i Leszek Królicki. "Tele NEN — zastosowanie telemedycyny w postępowaniu w nowotworach neuroendokrynnych na przykładzie NET uchyłka Meckela". Endokrynologia Polska 69, nr 3 (25.06.2018): 313–17. http://dx.doi.org/10.5603/ep.2018.0033.
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Hamzei, Amin, Hossein Hajiabadi i Morteza Torabi Rad. "Wettability of net C, net W and net Y: a molecular dynamics simulation study". RSC Advances 13, nr 4 (2023): 2318–28. http://dx.doi.org/10.1039/d2ra07811b.
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Aumann, Hartmut H., Alexander Ruzmaikin i Ali Behrangi. "On the Surface Temperature Sensitivity of the Reflected Shortwave, Outgoing Longwave, and Net Incident Radiation". Journal of Climate 25, nr 19 (4.04.2012): 6585–93. http://dx.doi.org/10.1175/jcli-d-11-00607.1.
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Abstract The global-mean top-of-atmosphere incident solar radiation (ISR) minus the outgoing longwave radiation (OLR) and the reflected shortwave radiation (RSW) is the net incident radiation (NET). This study analyzes the global-mean NET sensitivity to a change in the global-mean surface temperature by applying the interannual anomaly correlation technique to 9 yr of Atmospheric Infrared Sounder (AIRS) global measurements of RSW and OLR under cloudy and clear conditions. The study finds the observed sensitivity of NET that includes the effects of clouds to be −1.5 ± 0.25 (1σ) W m−2 K−1 and the clear NET sensitivity to be −2.0 ± 0.2 (1σ) W m−2 K−1, consistent with previous work using Earth Radiation Budget Experiment and Clouds and the Earth’s Radiant Energy System data. The cloud effect, +0.5 ± 0.2 (1σ) W m−2 K−1, is a positive component of the NET sensitivity. The similarity of the NET sensitivities derived from forced and unforced models invites a comparison between the observed sensitivities and the effective sensitivities calculated for the Fourth Assessment Report models, although this requires some caution: The effective model sensitivities with clouds range from −0.88 to −1.64 W m−2 K−1, the clear NET sensitivity in the models ranges from −2.32 to −1.73 W m−2 K−1, and the cloud forcing sensitivities range from +0.14 to +1.18 W m−2 K−1. The effective NET and clear NET sensitivities derived from the models are statistically consistent with those derived from the AIRS data, considering the observational and model derivation uncertainties.
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Starzyk, Justyna, Anna Such, Dominika Drab i Elżbieta Kołaczkowska. "SARS-CoV-2 a neutrofile: w sieci neutrofilowych pułapek zewnątrzkomórkowych NET". Kosmos 70, nr 3 (13.12.2021): 419–35. http://dx.doi.org/10.36921/kos.2021_2810.
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Choroba COVID-19 wywołana przez wirusa SARS-CoV-2 powoduje poważne uszkodzenia płuc, ale także innych narządów w organizmie człowieka. Infekcja może spowodować bardzo silną aktywację odpowiedzi immunologicznej, zwłaszcza wrodzonej, prowadząc m.in. do nadmiernej aktywacji neutrofili. Komórki te, stanowiące liczebnie największą populację leukocytów we krwi człowieka, po silnej aktywacji mogą wyrzucać tzw. zewnątrzkomórkowe sieci neutrofilowe NET. Struktury te mają na celu wyłapywanie i unieruchamianie (ograniczając infekcję) patogenów takich jak bakterie i wirusy. Jednak ze względu na fakt, że w ich skład wchodzą białka i kwasy nukleinowe silnie cytotoksyczne oraz aktywujące kaskadę krzepnięcia i układ dopełniacza, uszkodzeniu mogą ulegać także tkanki własne organizmu. W artykule przedstawiamy budowę, funkcje i efekty uboczne tworzenia NET w organizmie człowieka, a przede wszystkim opisujemy obecny stan wiedzy dotyczący wpływu NET na przebieg COVID-19. NET są silnie indukowane przez SARS-CoV-2, prowadząc do procesów patologicznych w trakcie COVID-19, w tym uszkodzeń wielonarządowych, m.in. związanych z tworzeniem zakrzepów. Przedstawimy także testowane oraz potencjalne, terapie anty-NET mogące poprawić stan chorych i/lub ochronić przed śmiercią.
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Das, Sushmita, Ankur Deka, Yuji Iwahori, M. K. Bhuyan, Takashi Iwamoto i Jun Ueda. "Contour-Aware Residual W-Net for Nuclei Segmentation". Procedia Computer Science 159 (2019): 1479–88. http://dx.doi.org/10.1016/j.procs.2019.09.318.
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Adamczyk-Gruszka, Olga, Jakub Gruszka, Grzegorz Świercz i Anna Zwierzyńska. "Zespół rakowiaka: kliniczny opis przypadku rakowiaka: opuszki dwunastnicy, płuca, raka jasnokomórkowego nerki." Journal of Education, Health and Sport 12, nr 3 (13.03.2022): 42–52. http://dx.doi.org/10.12775/jehs.2022.12.03.004.
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Chirurgia bariatryczna w ostatnich latach jest najbardziej rozpowszechnioną, a zarazem najskuteczniejszą metodą w leczeniu otyłości. Jest najskuteczniejszą opcją terapeutyczną dla pacjentów otyłych, wiąże się jednak z dużym ryzykiem zabiegu operacyjnego, oraz powikłaniami późnymi związanymi z zaburzeniami hormonalnymi, hipoglikemią, osteoporozą, zespołem złego wchłaniania. W ostatnich latach zwiększa się liczba operacji bariatrycznych z udziałem niezależnych procedur medycznych. Pacjent oraz lekarze biorący udział w planowanej operacji i dalszym leczeniu powinni być świadomi możliwych zagrożeń i powikłań związanych z otyłością patologiczną i zastosowanym leczeniem. Rakowiak żołądka (GC) zwany guzem neuroendokrynny żołądka jest rzadkim nowotworem wywodzącym się z komórek enterochromafinopodobnych żołądka. Ponad 75% GC to widoczne zmiany w endoskopii, pozostała część znajduje się w błonie śluzowej i nie jest identyfikowana w badaniu endoskopowym. Dlatego wymagana jest mapa żołądka z biopsjami odbytu i dna żołądka, aby potwierdzić jego obecność. W aktualnych klasyfikacjach NET zaleca się, aby guzy neuroendokrynne (pNET) guzy trzustki oraz guzy NET w innych lokalizacjach, były klasyfikowane jako guzy neuroendokrynne (NET)
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Maass, Wolfgang. "Neural Nets with Superlinear VC-Dimension". Neural Computation 6, nr 5 (wrzesień 1994): 877–84. http://dx.doi.org/10.1162/neco.1994.6.5.877.
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It has been known for quite a while that the Vapnik-Chervonenkis dimension (VC-dimension) of a feedforward neural net with linear threshold gates is at most O(w · log w), where w is the total number of weights in the neural net. We show in this paper that this bound is in fact asymptotically optimal. More precisely, we exhibit for any depth d ≥ 3 a large class of feedforward neural nets of depth d with w weights that have VC-dimension Ω(w · log w). This lower bound holds even if the inputs are restricted to Boolean values. The proof of this result relies on a new method that allows us to encode more “program-bits” in the weights of a neural net than previously thought possible.
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Zentner, R. P., B. G. McConkey, C. A. Campbell, F. B. Dyck i F. Selles. "Economics of conservation tillage in the semiarid prairie". Canadian Journal of Plant Science 76, nr 4 (1.10.1996): 697–705. http://dx.doi.org/10.4141/cjps96-121.
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Concerns about environmental sustainability and economic survival have changed tillage practices significantly in western Canada. This study examined the effects of conventional (CT), minimum (MT), and no-tillage (NT) management on the economic performance of hard red spring wheat (Triticium aestivum L.) or durum wheat (Triticum turgidum L.) production when grown in fallow–wheat (F–W) and continuous wheat (Cont W) rotations, over a period of up to 12 yr (1982–1993) on three soil textures in southwestern Saskatchewan. Our results show little short-term economic incentive for producers to adopt NT management practices. Production costs were similar on the three soil textures, averaging $141 ha−1 for F–W and $224 ha−1 for Cont W. Total costs for Cont W systems averaged 10 to 13% higher for NT compared to CT. For F–W systems total costs for NT averaged 29% higher than for CT on the silt loam, and 14% higher on the heavy clay. Also for F–W systems costs for NT averaged 23, 12, and 17% higher than for MT on silt loam, sandy loam, and heavy clay soils, respectively. Although conservation tillage (MT and NT) provided savings in labor, fuel and oil, machine repair, and machine overhead (compared to CT), these savings were more than offset by greater expenditures for herbicides. On the silt loam, net returns were highest for Cont W (CT) and lowest for F–W (NT) at wheat prices greater than $147 t−1; at lower wheat prices, F–W (CT) and Cont W (CT) provided the highest and about equal net returns. On the sandy loam, F–W (MT) consistently earned the highest net return; F–W (NT) ranked second highest, while Cont W systems ranked lowest. On the heavy clay, F–W (MT) and Cont W (CT) provided the highest net return at wheat prices greater than $147 t−1, while at lower wheat prices F–W (MT) ranked highest. In our study, the relatively poor economic performance of conservation tillage, particularly NT, for monoculture wheat production was due to a combination of higher input costs and the lack of significant yield advantages with MT and NT management. Key words: Minimum tillage, no-tillage, net returns, production costs, riskiness
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Sun, Yulu, Fuyao Qu, Xianjin Zhu, Bei Sun, Guojiao Wang, Hong Yin, Tao Wan, Xiaowen Song i Qian Chen. "Non-linear responses of net ecosystem productivity to gradient warming in a paddy field in Northeast China". PeerJ 8 (10.06.2020): e9327. http://dx.doi.org/10.7717/peerj.9327.
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Global warming has a known impact on ecosystems but there is a lack of understanding about its impact on ecosystem processes. Net ecosystem productivity (NEP) and its components play a key part in the global carbon cycle. Analysing the impact of global warming on NEP will improve our understanding of how warming affects ecosystems. In our study, conducted in 2018, five warming treatments were manipulated (0 W, 500 W, 1000 W, 1500 W, and 3000 W) using three repetitions of far infrared open warming over a paddy field in Northeast China. NEP and its two related components, gross primary productivity (GPP) and ecosystem respiration (ER), were measured using the static chamber-infrared gas analyser method to explore the effects of different warming magnitudes on NEP. Results showed that measurement dates, warming treatments, and their interactions significantly affected NEP, ER, and GPP. Warming significantly increased NEP and its components but they showed a non-linear response to different warming magnitudes. The maximum increases in NEP and its components occurred at 1500 W warming. NEP is closely related to its components and the non-linear response of NEP may have primarily resulted from that of GPP. Gradient warming non-linearly increased GPP in the paddy field studied in Northeast China, resulting in the non-linear response of NEP. This study provides a basis for predicting the responses of carbon cycles in future climate events.
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Kovun, Vladislav A., i Irina L. Kashirina. "USAGE OF U-NET AND W-NET NEURAL NETWORK ARCHITECTURES FOR STEEL SAMPLES METALLOGRAPHIC ANALYSIS". Вестник ВГУ Серия Системный анализ и информационные технологии, nr 1 (2022): 101–10. http://dx.doi.org/10.17308/sait.2022.1/9205.
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Ge, Nan, Lei Zhong, Yaoming Ma, Meilin Cheng, Xian Wang, Mijun Zou i Ziyu Huang. "Estimation of Land Surface Heat Fluxes Based on Landsat 7 ETM+ Data and Field Measurements over the Northern Tibetan Plateau". Remote Sensing 11, nr 24 (5.12.2019): 2899. http://dx.doi.org/10.3390/rs11242899.
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Land surface heat fluxes consist of the net radiation flux, soil heat flux, sensible heat flux, and latent heat flux. The estimation of these fluxes is essential to the study of energy transfer in land–atmosphere systems. In this paper, Landsat 7 ETM+ SLC-on data were applied to estimate the land surface heat fluxes on the northern Tibetan Plateau using the SEBS (surface energy balance system) model, in combination with the calculation of field measurements at CAMP/Tibet (Coordinated Enhanced Observing Period (CEOP) Asia–Australia Monsoon Project on the Tibetan Plateau) automatic weather stations based on the combinatory method (CM) for comparison. The root mean square errors between the satellite estimations and the CM calculations for the net radiation flux, soil heat flux, sensible heat flux, and latent heat flux were 49.2 W/m2, 46.3 W/m2, 68.2 W/m2, and 54.9 W/m2, respectively. The results reveal that land surface heat fluxes all present significant seasonal variability. Apart from the sensible heat flux, the satellite-estimated net radiation flux, soil heat flux, and latent heat flux exhibited a trend of summer > spring > autumn > winter. In summer, spring, autumn, and winter, respectively, the median values of the net radiation flux (631.8 W/m2, 583.0 W/m2, 404.4 W/m2, 314.3 W/m2), soil heat flux (40.9 W/m2, 37.9 W/m2, 26.1 W/m2, 20.5 W/m2), sensible heat flux (252.7 W/m2, 219.5 W/m2, 221.4 W/m2, 204.8 W/m2), and latent heat flux (320.1 W/m2, 298.3 W/m2, 142.3 W/m2, 75.5 W/m2) exhibited distinct seasonal diversity. From November to April, the in situ sensible heat flux is higher than the latent heat flux; the opposite is true between June and September, leaving May and October as transitional months. For water bodies, alpine meadows and other main underlying surface types, sensible and latent heat flux generally present contrasting and complementary spatial distributions. Due to the 15–60 m resolution of the Landsat 7 ETM+ data, the distribution of land surface heat fluxes can be used as an indicator of complex underlying surface types over the northern Tibetan Plateau.
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Shao, C., J. Chen, L. Li, G. Tenney, W. Xu i J. Xu. "Role of net radiation on energy balance closure in heterogeneous grasslands". Biogeosciences Discussions 8, nr 2 (1.03.2011): 2001–33. http://dx.doi.org/10.5194/bgd-8-2001-2011.
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Abstract. Low energy balance closure (EBC) at a particular eddy-covariance flux site increased the uncertainties of carbon, water and energy measurements and thus hampered the urgent research of scaling up and modeling analysis through site combinations. A series of manipulative experiments were conducted in this study to explore the role of net radiation (Rn) in the EBC in relation to spatial variability of vegetation characteristics, source area, sensor type, and dome condition in the Inner Mongolian grassland of Northern China. At all three sites, the daytime peak residual fluxes of EBC were consistently about 100 W m−2 regardless of radiometers (i.e., REBS Q7.1 or CNR1). The spatial variability in net radiation was 19 W m−2 (5% of Rn) during the day and 7 W m−2 (16%) at night, with an average of 13 W m−2 (11%) from eight plot measurements across the three sites. Net radiation results were affected more by measurement source area in unclipped heterogeneous system than in clipped homogeneous vegetation. Large area measurement significantly (P<0.0001) increased by 9 W m−2 during the day and decreased by 4 W m−2 at night in unclipped treatments. With an increase in clipping intensity, net radiation decreased by 25 W m−2 (6% of Rn) at midday and 81 MJ m−2 (6%) during a growing season with heavier regular clipping than that in unclipped treatments. Additional effort in EBC between 9:00 and 15:00 LT is needed for future research because of high variation. Using this method, the EBC difference derived from the two types of net radiometers was only 6 W m−2. Results from Q7.1 with new domes were higher during the day but lower at night than those with used domes. Overall, the inclusion of the uncertainty in available energy accounted for 60% of the 100 W m−2 shortfalls in the lack of closure. Clearly, the unclosed energy balance at these three grassland sites remains significant, with unexplored mechanisms for future research.
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ZENTNER, R. P., J. E. STEPHENSON, P. J. JOHNSON, C. A. CAMPBELL i G. P. LAFOND. "THE ECONOMICS OF WHEAT ROTATIONS ON A HEAVY CLAY CHERNOZEMIC SOIL IN THE BLACK SOIL ZONE OF EAST-CENTRAL SASKATCHEWAN". Canadian Journal of Plant Science 68, nr 2 (1.04.1988): 389–404. http://dx.doi.org/10.4141/cjps88-050.
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The effects of changes in product prices and input costs on the economic performance of 14 spring wheat (Triticum aestivum L.) rotations on a calcareous Black chernozemic heavy clay soil at Indian Head, Saskatchewan were examined over 25 yr. The rotations comprised fertilized and unfertilized treatments and several mixed cereal-oilseed and cereal-legume systems. In 1960–1977 the fertilized rotations received N and P according to the generally recommended rates for the region, but during 1978–1984 fertilizer was applied based on soil tests which resulted in substantially higher rates of N for stubble crops. Four of the rotations showed good economic performance under most reasonable economic situations. These included fertilized fallow-wheat-wheat (F-W-W), fertilized continuous wheat, unfertilized sweet clover [Melilotus officinalis (L.) Lam.] green manure-wheat-wheat (Gm-W-W), and unfertilized fallow-wheat-wheat- legume hay-hay-hay (F-W-W-H-H-H). During the first 18 yr, Gm-W-W provided the highest net income for wheat prices ranging from 73 to 221 $ t−1; F-W-W-H-H-H generally ranked second highest. During the last 7 yr, fertilized continuous wheat was most profitable for wheat prices greater than 180 $ t−1. Continuous wheat, F-W-W, and F-W-W-H-H-H were about equal and provided the highest net income for wheat prices between 145 and 180 $ t−1, while at wheat prices below 145 $ t−1 net income was highest for the legume-containing rotations. Except for the fallow-wheat rotation, higher economic benefits were obtained when fertilizer was applied based on soil tests than when based on the general recommendations for the region. Further, the application of fertilizer reduced the cash cost per unit of wheat produced for the more intensive crop rotations. Rotations containing high proportions of fallow or legume crops generally had the lowest frequency and risk of financial loss.Key words: Crop rotations, net income, input costs, income variability, riskiness
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Zentner, R. P., C. A. Campbell, F. Selles, R. Lemke, B. G. McConkey, M. R. Fernandez, C. Hamel i Y. T. Gan. "Economics of spring wheat production systems using conventional tillage management in the Brown soil zone – Revisited". Canadian Journal of Plant Science 87, nr 1 (1.01.2007): 27–40. http://dx.doi.org/10.4141/p05-219.
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Producers in the semiarid Brown soil zone of the Canadian Prairies have historically used fallow (F)-based cropping systems with mechanical tillage methods to produce spring wheat (Triticum aestivum L.) (W). However, in the past two decades government policies and programs have changed, as have cropping practices, market opportunities, and weather patterns. This study re-examines the economic merits of these conventional cropping systems under today’s conditions in regard to the optimal cropping frequency, value of applying N and P fertilizer at soil test rates, and the possible advantage of replacing monoculture wheat with lentil (Lens culinaris Medikus) (Lent) or flax (Linum usitatissimum L.) (Flx) grown in mixed rotations. The analysis draws on data from a long-term crop rotation experiment that was established in 1967 on an Orthic Brown Chernozem at the Semiarid Prairie Agricultural Research Centre at Swift Current, Saskatchewan. All cropping systems were managed using conventional tillage practices, which attempted to conserve as much surface crop residue as possible (i.e., stubble mulch tillage techniques were used). The findings for 1985–2002, a period characterized by above normal precipitation, were compared with those reported previously for the 1967–1984 period when growing conditions were less favorable but more typical for this area. Net returns during 1985–2002 were highest for W-Lent ($93 ha-1 yr-1) and lowest for F-Flx-W ($38 ha-1 yr-1). Net returns for well-fertilized F-W, F-W-W, F-W-W-W-W-W, and Cont W during this same period were similar, averaging about $52 ha-1 yr-1 or 44% less than for W-Lent. These results contrast with those reported for the previous 18-yr period when F-W and F- W-W generally produced higher net returns than Cont W. Within the F-W-W systems, the application of both N and P fertilizer increased the 18-yr (1985–2002) mean net returns by $18 ha-1 yr-1 compared with application of N only, and by $32 ha-1 yr-1 compared with application of P only. For Cont W the application of N and P fertilizer increased the mean net returns by $71 ha-1 yr-1 compared with application of P only. These economic benefits from N and P fertilization were much higher than those reported in 1967–1984 due to the more humid growing conditions and the increased rate of N fertilizer prescribed by the soil testing lab since 1991. Further, our findings showed that only if producers were highly risk averse, do not subscribe to all-risk crop insurance , or if the price for wheat was high or price for lentil low, would the monoculture wheat systems be preferred to W-Lent. However, producers who are highly risk averse would still opt for the cropping systems that included some summerfallow. Our findings support the recent trends in land use practices by area producers towards more diversified and intensive cropping systems which are less reliant on frequent fallowing. Key words: Crop rotations, wheat, lentil, flax, summerfallow, production costs, net returns, income variability
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Sunmonu, L. A., A. I. Ajao, M. A. Ayoola, E. O. Ogolo, O. A. Babatunde i O. O. Jegede. "Evaluation of the performances of two rebs net radiometer designs during Nimex at a tropical site in Ile-Ife, Nigeria". Ife Journal of Science 22, nr 2 (24.08.2020): 111–23. http://dx.doi.org/10.4314/ijs.v22i2.11.
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In this study, the performances of two types of Radiation Energy Balance Systems (REBS) net radiometers, a domed (model Q-7.1) and domeless (model NR-LITE) against a reference, four-component net radiometer (model NR01), are evaluated during the conduct of Nigeria Micrometeorological Experiment (NIMEX) held between May 27 and June 12, 2013 at a tropical location in Ile-Ife, Nigeria. During the daytime, net radiation measurements made by NR-LITE and Q-7.1 showed good agreements with NR01, with coefficient of determination for both > 0.90. The values of the mean and standard deviation for daytime net radiation as measured by NR01, NR-LITE and Q-7.1 were 257.7 ± 174.7 W m2 , 179.6 ± 129.3 W m2 and 240.6 ± 153.1 W m2 , respectively. At nighttime, NR-LITE net radiometer responded to longwave radiation better than Q-7.1. Adjustments made by linear regression of NR-LITE and Q-7.1 datasets with NR01 produced better fit. Though costs of the two REBS type net radiometers are comparatively the same, Q-7.1 performed better than NRLITE. However, for long-term operation, the Q-7.1 type requires periodic (every 2-3 months) changing of the plastic domes due to ageing and cracking, unlike the NR-LITE. So, the NR-LITE is a preferred option to be adopted by the Weather Services in West African countries for routine measurements of net radiation because it does not require periodic changing of the plastic domes.
Keywords: Net radiation; REBS net radiometers; 4-component net radiometer; tropical location.
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Hussein, Maged M. A. "Mean Daily Variability of Energy Fluxes Above Alexandria Eastern Harbor". ATHENS JOURNAL OF SCIENCES 8, nr 3 (30.08.2021): 183–98. http://dx.doi.org/10.30958/ajs.8-3-2.
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Mean daily variability of latent heat (E), sensible heat (H), net long wave (Lwnet), net short wave, and net flux of surface heat balance were estimated from hourly sea surface water temperature (SST) and meteorological time series obtained for three months during summer season (2019) in Alexandria Eastern Harbor (AEH), Egypt. Latent and sensible heat were not in phase and had their maximum 181.12 W/m2 (5:00 PM), 16.5 W/m2 (5:00 AM) and minimum 103.64 W/m2 (8:00 AM), -12.14 W/m2 (3:00 PM), resulting in Bowen ration of -0.11 and 0.09, respectively. The loss of heat by evaporation therefore predominates than sensible heat utilized to warm surface atmosphere. The instability of the atmosphere was existing nearly most of the time period, rising exchange coefficients of sensible and latent heat flux by about 24.26% over estimated neutral values (from 1.15 × 10−3 to 1.43 × 10−3). Mean Lwnet changed from 165.63 at early morning to 173.52 W/m2 at late afternoon, point out its significant importance in the total balance of heat flux of eastern harbor surface. Latent heat flux and Lwnet were positive (energy losing from eastern harbor), throughout the day. The daily average of net energy budget (S) was 38.52 W/m2; daytime gain exceeded nighttime loss, with consequent heating the eastern harbor. Qualitatively, daily variations of net energy budget (S) were nearly consistent with time delay to the variability of sea surface temperature, indicating the predominant role of the heat budget of the surface layer in modulating surface temperatures of the Eastern Harbor. Keywords: heat flux, shortwave, long wave, latent heat, sensible heat, Eastern Harbor
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Yu, Yongmei, Zhaofeng Du, Changxin Yuan i Jian Li. "Exploration of CT Images Based on the BN-U-net-W Network Segmentation Algorithm in Glioma Surgery". Contrast Media & Molecular Imaging 2022 (11.04.2022): 1–10. http://dx.doi.org/10.1155/2022/4476412.
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This study aimed to explore the application value of computed tomography (CT) imaging features based on the deep learning batch normalization (batch normalization, BN) U-net-W network image segmentation algorithm in evaluating and diagnosing glioma surgery. 72 patients with glioma who were admitted to hospital were selected as the research subjects. They were divided into a low-grade group (grades I-II, N = 27 cases) and high-grade group (grades III-IV, N = 45 cases) according to postoperative pathological examination results. The CT perfusion imaging (CTPI) images of patients were processed by using the deep learning-based BN-U-net-W network image segmentation algorithm. The application value of the algorithm was comprehensively evaluated by comparing the average Dice coefficient, average recall rate, and average precision of the BN-U-net-W network image segmentation algorithm with the U-net and BN-U-net network algorithms. The results showed that the Dice coefficient, recall, and precision of the BN-U-net-W network were 86.31%, 88.43%, and 87.63% respectively, which were higher than those of the U-net and BN-U-net networks, and the differences were statistically significant ( P < 0.05 ). Cerebral blood flow (CBF), cerebral blood volume (CBV), and capillary permeability (PMB) in the glioma area were 56.85 mL/(min·100 g), 18.03 mL/(min·100 g), and 8.57 mL/100 g, respectively, which were significantly higher than those of normal brain tissue, showing statistically significant differences ( P < 0.05 ). The mean transit time (MTT) difference between the two was not statistically significant ( P > 0.05 ). The receiver operating characteristic (ROC) curves of CBF, CBV, and PMB in CTPI parameters of glioma had area under the curve (AUC) of 0.685, 0.724, and 0.921, respectively. PMB parameters were significantly higher than those of CBF and CVB, and the differences were statistically obvious ( P < 0.05 ). It showed that the BN-U-net-W network model had a better image segmentation effect, and CBF, CBV, and PMB showed better sensitivity in diagnosing glioma tissue and normal brain tissue and high-grade and low-grade gliomas, among which PBM showed the highest predictability.
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Nordsborg, Nikolai B., José A. L. Calbet, Mikael Sander, Gerrit van Hall, Carsten Juel, Bengt Saltin i Carsten Lundby. "Human muscle net K+ release during exercise is unaffected by elevated anaerobic metabolism, but reduced after prolonged acclimatization to 4,100 m". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 299, nr 1 (lipiec 2010): R306—R313. http://dx.doi.org/10.1152/ajpregu.00062.2010.
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It was investigated whether skeletal muscle K+ release is linked to the degree of anaerobic energy production. Six subjects performed an incremental bicycle exercise test in normoxic and hypoxic conditions prior to and after 2 and 8 wk of acclimatization to 4,100 m. The highest workload completed by all subjects in all trials was 260 W. With acute hypoxic exposure prior to acclimatization, venous plasma [K+] was lower ( P < 0.05) in normoxia (4.9 ± 0.1 mM) than hypoxia (5.2 ± 0.2 mM) at 260 W, but similar at exhaustion, which occurred at 400 ± 9 W and 307 ± 7 W ( P < 0.05), respectively. At the same absolute exercise intensity, leg net K+ release was unaffected by hypoxic exposure independent of acclimatization. After 8 wk of acclimatization, no difference existed in venous plasma [K+] between the normoxic and hypoxic trial, either at submaximal intensities or at exhaustion (360 ± 14 W vs. 313 ± 8 W; P < 0.05). At the same absolute exercise intensity, leg net K+ release was less ( P < 0.001) than prior to acclimatization and reached negative values in both hypoxic and normoxic conditions after acclimatization. Moreover, the reduction in plasma volume during exercise relative to rest was less ( P < 0.01) in normoxic than hypoxic conditions, irrespective of the degree of acclimatization (at 260 W prior to acclimatization: −4.9 ± 0.8% in normoxia and −10.0 ± 0.4% in hypoxia). It is concluded that leg net K+ release is unrelated to anaerobic energy production and that acclimatization reduces leg net K+ release during exercise.
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Wang, Ge, Lin Han i Xingying Tang. "Land-Atmosphere Energy Exchange Characteristics in Ali of Tibetan". Advances in Meteorology 2022 (11.08.2022): 1–6. http://dx.doi.org/10.1155/2022/7374193.
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Based on the comprehensive data from the land-atmosphere interaction observation station in Ali of Tibetan in 2019, the characteristics of land-atmosphere energy exchange processes in Ali were analyzed. The results indicated that the timing of the mean intraday net radiation peak in Ali over the past 20 years has been delayed, and the month when the maximum monthly mean net radiation occurred has been delayed by about 2 months; the maximum daily mean, maximum monthly mean, minimum monthly mean, and annual mean sensible heat were 99.63 w/m2, 76.53 w/m2, 17.47 w/m2, and 46.74 w/m2, respectively, and the maximum daily mean, maximum monthly mean, minimum monthly mean, and annual mean latent heat flux were 73.27 w/m2, 36.13 w/m2, 0.67 w/m2, and 8.32 w/m2, respectively; and the monthly mean sensible heat was greater than the latent heat in all months.
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Scales, Pamela F., i R. L. Peterson. "Structure and development of Pinus banksiana – Wilcoxina ectendomycorrhizae". Canadian Journal of Botany 69, nr 10 (1.10.1991): 2135–48. http://dx.doi.org/10.1139/b91-268.
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Seedlings of Pinus banksiana were grown in growth pouches and inoculated with Wilcoxina mikolae var. mikolae, Wilcoxina mikolae var. tetraspora, and Wilcoxina rehmii. Ectendomycorrhizae formed between P. banksiana and W. mikolae var. mikolae developed rapidly following inoculation. The mantle was of variable width, and a large amount of mucigel was evident on the root surface. Intracellular penetration of the cortical cells by hyphae occurred one to two cells distal to Hartig net formation. Both light and transmission electron microscopy revealed labyrinthic growth of Hartig net hyphae that were densely cytoplasmic during early penetration stages but became vacuolate as the association aged. Intracellular colonization of the cortex was extensive, with the hyphae highly branched and surrounded by an interfacial matrix and cortical cell plasma membrane. The external morphology and anatomy of ectendomycorrhizae formed between W. mikolae var. tetraspora and W. rehmii and P. banksiana were similar to those described for W. mikolae var. mikolae. Key words: ectendomycorrhizae, Wilcoxina, Pinus banksiana, intracellular, Hartig net, E-strain.
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Dorfman, L. P., D. L. Houck i M. J. Scheithauer. "Consolidation of tungsten-coated copper composite powder". Journal of Materials Research 17, nr 8 (sierpień 2002): 2075–84. http://dx.doi.org/10.1557/jmr.2002.0307.
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Powder metallurgy (P/M) methods have expanded in recent years to include net-shape fabrication of W–Cu components. Sintering of W–Cu compacts made from previous powders has led to low density and copper bleedout. This paper presents test results on the consolidation of a new powder containing particles composed of a tungsten-coated copper core. This powder effectively eliminates copper bleedout at sintering thereby making possible the net-shape manufacturing of parts. Sintered articles are characterized by microstructural homogeneity and properties comparable to those of infiltrated W–Cu composites.
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Wang, Xue, Xulan Yan, Kun Tan, Chen Pan, Jianwei Ding, Zhaoxian Liu i Xinfeng Dong. "Double U-Net (W-Net): A change detection network with two heads for remote sensing imagery". International Journal of Applied Earth Observation and Geoinformation 122 (sierpień 2023): 103456. http://dx.doi.org/10.1016/j.jag.2023.103456.
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Visioni, Daniele, Giovanni Pitari, Glauco di Genova, Simone Tilmes i Irene Cionni. "Upper tropospheric ice sensitivity to sulfate geoengineering". Atmospheric Chemistry and Physics 18, nr 20 (17.10.2018): 14867–87. http://dx.doi.org/10.5194/acp-18-14867-2018.
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Abstract. Aside from the direct surface cooling that sulfate geoengineering (SG) would produce, investigations of the possible side effects of this method are still ongoing, such as the exploration of the effect that SG may have on upper tropospheric cirrus cloudiness. The goal of the present study is to better understand the SG thermodynamical effects on the freezing mechanisms leading to ice particle formation. This is undertaken by comparing SG model simulations against a Representative Concentration Pathway 4.5 (RCP4.5) reference case. In the first case, the aerosol-driven surface cooling is included and coupled to the stratospheric warming resulting from the aerosol absorption of terrestrial and solar near-infrared radiation. In a second SG perturbed case, the surface temperatures are kept unchanged with respect to the reference RCP4.5 case. When combined, surface cooling and lower stratospheric warming tend to stabilize the atmosphere, which decreases the turbulence and updraft velocities (−10 % in our modeling study). The net effect is an induced cirrus thinning, which may then produce a significant indirect negative radiative forcing (RF). This RF would go in the same direction as the direct effect of solar radiation scattering by aerosols, and would consequently influence the amount of sulfur needed to counteract the positive RF due to greenhouse gases. In our study, given an 8 Tg-SO2 yr−1 equatorial injection into the lower stratosphere, an all-sky net tropopause RF of −1.46 W m−2 is calculated, of which −0.3 W m−2 (20 %) is from the indirect effect on cirrus thinning (6 % reduction in ice optical depth). When surface cooling is ignored, the ice optical depth reduction is lowered to 3 %, with an all-sky net tropopause RF of −1.4 W m−2, of which −0.14 W m−2 (10 %) is from cirrus thinning. Relative to the clear-sky net tropopause RF due to SG aerosols (−2.1 W m−2), the cumulative effect of the background clouds and cirrus thinning accounts for +0.6 W m−2, due to the partial compensation of large positive shortwave (+1.6 W m−2) and negative longwave adjustments (−1.0 W m−2). When surface cooling is ignored, the net cloud adjustment becomes +0.8 W m−2, with the shortwave contribution (+1.5 W m−2) almost twice as much as that of the longwave (−0.7 W m−2). This highlights the importance of including all of the dynamical feedbacks of SG aerosols.
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JOYDEEP MUKHERJEE, S.K. BAL, GURJOT SINGH, B.K. BHATTACHARYA, HARPREET SINGH i PRABHJYOT KAUR. "Surface energy fluxes in wheat (Triticum aestivum L.) under irrigated ecosystem". Journal of Agrometeorology 14, nr 1 (1.06.2012): 16–20. http://dx.doi.org/10.54386/jam.v14i1.1372.
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The surface energy fluxes were measured over irrigated wheat during winter season. 2008-09 and 2009-10 sown on first week of November. Study revealed that the net radiation flux (Rn) varied from 420 to 693 was during 2008-09 and 328 to 926 W m-2 during 2009-10 in different growth stages. The soil heat flux was higher during initial and senescence growth stages (13 to 15 % of net radiations) as compared to peak crop growth stages (6 to 9 % of net radiations). The latent heat flux showed apparent correspondence with the growth which varied from 247 to 387 W m-2 during 2008-09 and 209 to 569 W m-2 during 2009-10 in different growth stages. Study revealed that LAI was positively related with intercepted photosynthetically active radiation (IPAR).
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Wu, Lingwei, i Guihua Wang. "Surface net heat flux estimated from drifter observations". Environmental Research Letters 17, nr 9 (19.08.2022): 094009. http://dx.doi.org/10.1088/1748-9326/ac8821.
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Abstract The ocean mixed layer temperature equation is used to estimate the surface net heat flux from drifter measurements. The net heat flux is determined for both the climatologic and tropical cyclone (TC) conditions. The spatial distributions of the drifter-derived heat fluxes under both the two conditions are similar to those derived from satellite observations. However, the drifter-derived climatologic heat flux appears to be weaker in magnitude than that derived from satellites, and performs better in closing the energy budget with a global mean value of 3.9 W m−2. The drifter-derived heat flux also performs better than the satellite-derived heat flux under TCs, using the buoy observations as a reference considering metrics such as the meen error, mean absolute error, root mean-square error and percent bias. The spatially averaged mean net heat flux derived from drifters under TCs is −124 W m−2 at 10° N, and decreases to −85 W m−2 at 30° N, however, these values are much larger than those obtained from satellites (−63 W m−2 and −21 W m−2, respectively). As additional components for the mixed layer temperature equation, both the entrainment velocity and eddy diffusivity in climatology show large amplitudes in regions with strong currents such as the Western Boundary Current and Antarctic Circumpolar Current. However, under TC conditions large values of the entrainment velocity and eddy diffusivity mostly appear in regions with strong winds.
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Xiong, Y., M. Kim, O. Seo, J. M. Schoenung i S. Kang. "(Ti,W)C–Ni cermets by laser engineered net shaping". Powder Metallurgy 53, nr 1 (marzec 2010): 41–46. http://dx.doi.org/10.1179/174329009x380581.
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Pan, Weihao, Zhe Liu, Weichen Song, Xuyang Zhen, Kai Yuan, Fei Xu i Guan Ning Lin. "An Integrative Segmentation Framework for Cell Nucleus of Fluorescence Microscopy". Genes 13, nr 3 (26.02.2022): 431. http://dx.doi.org/10.3390/genes13030431.
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Nucleus segmentation of fluorescence microscopy is a critical step in quantifying measurements in cell biology. Automatic and accurate nucleus segmentation has powerful applications in analyzing intrinsic characterization in nucleus morphology. However, existing methods have limited capacity to perform accurate segmentation in challenging samples, such as noisy images and clumped nuclei. In this paper, inspired by the idea of cascaded U-Net (or W-Net) and its remarkable performance improvement in medical image segmentation, we proposed a novel framework called Attention-enhanced Simplified W-Net (ASW-Net), in which a cascade-like structure with between-net connections was used. Results showed that this lightweight model could reach remarkable segmentation performance in the BBBC039 testing set (aggregated Jaccard index, 0.90). In addition, our proposed framework performed better than the state-of-the-art methods in terms of segmentation performance. Moreover, we further explored the effectiveness of our designed network by visualizing the deep features from the network. Notably, our proposed framework is open source.
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L’Ecuyer, Tristan S., Yun Hang, Alexander V. Matus i Zhien Wang. "Reassessing the Effect of Cloud Type on Earth’s Energy Balance in the Age of Active Spaceborne Observations. Part I: Top of Atmosphere and Surface". Journal of Climate 32, nr 19 (26.08.2019): 6197–217. http://dx.doi.org/10.1175/jcli-d-18-0753.1.
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AbstractThis study revisits the classical problem of quantifying the radiative effects of unique cloud types in the era of spaceborne active observations. The radiative effects of nine cloud types, distinguished based on their vertical structure defined by CloudSat and CALIPSO observations, are assessed at both the top of the atmosphere and the surface. The contributions from single- and multilayered clouds are explicitly diagnosed. The global, annual mean net cloud radiative effect at the top of the atmosphere is found to be −17.1 ± 4.2 W m−2 owing to −44.2 ± 2 W m−2 of shortwave cooling and 27.1 ± 3.7 W m−2 of longwave heating. Leveraging explicit cloud base and vertical structure information, we further estimate the annual mean net cloud radiative effect at the surface to be −24.8 ± 8.7 W m−2 (−51.1 ± 7.8 W m−2 in the shortwave and 26.3 ± 3.8 W m−2 in the longwave). Multilayered clouds are found to exert the strongest influence on the top-of-atmosphere energy balance. However, a strong asymmetry in net cloud radiative cooling between the hemispheres (8.6 W m−2) is dominated by enhanced cooling from stratocumulus over the southern oceans. It is found that there is no corresponding asymmetry at the surface owing to enhanced longwave emission by southern ocean clouds in winter, which offsets a substantial fraction of their impact on solar absorption in summer. Thus the asymmetry in cloud radiative effects is entirely realized as an atmosphere heating imbalance between the hemispheres.
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Andreassen, Liss M., Michiel R. Van Den Broeke, Rianne H. Giesen i Johannes Oerlemans. "A 5 year record of surface energy and mass balance from the ablation zone of Storbreen, Norway". Journal of Glaciology 54, nr 185 (2008): 245–58. http://dx.doi.org/10.3189/002214308784886199.
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AbstractA 5 year record of data from an automatic weather station (AWS) operating in the ablation zone of Storbreen, Norway, has been used to calculate the local surface energy and mass balance. The AWS observations cover five mass-balance years with an unusually strong mass deficit on Storbreen. The average energy flux (Q) contributing to melt for the period 2001–06 is 113 W m−2. Of this, the net shortwave radiation flux is the dominant contributor (92 W m−2), followed by the sensible heat flux (20 W m−2) and the latent heat flux (9 W m−2). The net longwave radiation (–6 W m−2) and the subsurface heat flux (–2 W m−2) contribute negatively to the budget. Net radiation thus produces 76% of the melt, while the turbulent fluxes and the subsurface heat flux produce 24% of the total melt. The seasonal mean incoming shortwave radiation is remarkably constant between the years, whereas variations in temperature and reflected shortwave radiation (albedo) explain most of the interannual variation in melt. The modelled ablation compares well with the measured ablation from stake readings. The sensitivity of the energy-balance model was examined by varying the surface roughness length of momentum and the sensitivity of the calculated melt by perturbations of temperature, wind speed and relative humidity.
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Huang, Hai Ping, i Pin Wang. "Analyses on W&R and BIAS Expert System of Stock-Market Software". Applied Mechanics and Materials 433-435 (październik 2013): 2391–94. http://dx.doi.org/10.4028/www.scientific.net/amm.433-435.2391.
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According to extensive quantity of public and factual data, this essay does tests on BIAS and W&R expert system of stock-market trading software in simulation experiment method, and compares their strength and weakness in the respect of mathematical statistics theory and Management objects, winning rate, annual return rate and net profit rate. The tests show that BIAS expert system is 2.58 times as good as W&R expert system in the items of annual return rate and net profit rate, 0.26 times in the item of the total number of trading. As a whole, BIAS expert system is superior to W&R expert system.
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Hong, Yulan, Guosheng Liu i J. L. F. Li. "Assessing the Radiative Effects of Global Ice Clouds Based on CloudSat and CALIPSO Measurements". Journal of Climate 29, nr 21 (6.10.2016): 7651–74. http://dx.doi.org/10.1175/jcli-d-15-0799.1.
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Abstract Although it is well established that cirrus warms Earth, the radiative effect of the entire spectrum of ice clouds is not well understood. In this study, the role of all ice clouds in Earth’s radiation budget is investigated by performing radiative transfer modeling using ice cloud properties retrieved from CloudSat and CALIPSO measurements as inputs. Results show that, for the 2008 period, the warming effect (~21.8 ± 5.4 W m−2) induced by ice clouds trapping longwave radiation exceeds their cooling effect (~−16.7 ± 1.7 W m−2) caused by shortwave reflection, resulting in a net warming effect (~5.1 ± 3.8 W m−2) globally on the earth–atmosphere system. The net warming is over 15 W m−2 in the tropical deep convective regions, whereas cooling occurs in the midlatitudes, which is less than 10 W m−2 in magnitude. Seasonal variations of ice cloud radiative effects are evident in the midlatitudes where the net effect changes from warming during winter to cooling during summer, whereas warming occurs all year-round in the tropics. Ice cloud optical depth τ is shown to be an important factor in determining the sign and magnitude of the net radiative effect. Ice clouds with τ < 4.6 display a warming effect with the largest contributions from those with τ ≈ 1.0. In addition, ice clouds cause vertically differential heating and cooling of the atmosphere, particularly with strong heating in the upper troposphere over the tropics. At Earth’s surface, ice clouds produce a cooling effect no matter how small the τ value is.
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ZENTNER, R. P., J. E. STEPHENSON, C. A. CAMPBELL, K. E. BOWREN, A. MOULIN i L. TOWNLEY-SMITH. "EFFECTS OF ROTATION AND FERTILIZATION ON ECONOMICS OF CROP PRODUCTION IN THE BLACK SOIL ZONE OF NORTH-CENTRAL SASKATCHEWAN". Canadian Journal of Plant Science 70, nr 3 (1.07.1990): 837–51. http://dx.doi.org/10.4141/cjps90-101.
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Effects of changes in product prices and input costs on the economic performance of 10 spring wheat (Triticum aestivum L.) -based rotations grown on a highly fertile orthic Black Chernozemic silty clay loam soil at Melfort, Saskatchewan, were examined over the 27-yr period from 1960–1986. The rotations differed in frequency of summerfallow, N and P fertilization, and cropping sequence involving canola (Brassica napus L.), grass-legume hay [bromegrass (Bromus inermis Leyss.), alfalfa (Medicago sativa L.)], and legume green manure [sweetclover (Melilotus officinalis (L.) Lam)]. During 1960–1971 fertilized rotations received the generally recommended rates of N and P for the region, but during 1972–1986, fertilizer was applied based on soil tests. Net income, riskiness, and costs of production were calculated over a range of product prices and input costs. At wheat prices greater than $147 t−1, fertilized fallow-wheat-wheat (F-W-W), fertilized fallow-canola-wheat (F-C-W), and a 6-yr fertilized grass-legume hay (H) rotation (F-W-W-H-H-W), generally provided the best overall economic return. At lower wheat prices, unfertilized F-W-W and F-W-W-H-H-W and fertilized fallow-wheat (F-W) often provided net income similar to the above rotations. It was profitable to substitute canola for wheat grown on conventional fallow, or on partial fallow after grass-legume hay, when the ratio of canola to wheat price was greater than about 2.0. Similarly, it was profitable to include grass-legume hay in wheat rotations when the hay price was greater than one-half that of wheat. Continuous wheat and sweetclover green manure-wheat-wheat (Gm-W-W) were not economically competitive with the best rotations at any of the price options examined. Fertilizer application was profitable in F-W-W and continuous wheat when the ratio of fertilizer cost to wheat price was less than about 5.0; it was profitable in F-W-W-H-H-W when this ratio was less than 3.5. The cost of producing wheat increased directly with rotation length. Income variability and frequency of economic losses increased with cropping intensity; however, all-risk crop insurance was effective in minimizing financial risk.Key words: Wheat (spring), canola, hay, net income, costs, riskiness
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Worger, H. O. "The relationship between gross and net yields to redemption". Journal of the Institute of Actuaries 115, nr 3 (wrzesień 1988): 527–34. http://dx.doi.org/10.1017/s0020268100042803.
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1. With reference to the Actuarial Note by Messrs Hathaway, Rickard & Woods (HR&W) J.I.A.113, 509–520 there is a simpler way, which is much easier to calculate, of approximating from the gross yield to redemption to the net yield, with taxation on the basis assumed by HR&W.
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Zelinka, Mark D., Stephen A. Klein, Karl E. Taylor, Timothy Andrews, Mark J. Webb, Jonathan M. Gregory i Piers M. Forster. "Contributions of Different Cloud Types to Feedbacks and Rapid Adjustments in CMIP5*". Journal of Climate 26, nr 14 (12.07.2013): 5007–27. http://dx.doi.org/10.1175/jcli-d-12-00555.1.
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Abstract Using five climate model simulations of the response to an abrupt quadrupling of CO2, the authors perform the first simultaneous model intercomparison of cloud feedbacks and rapid radiative adjustments with cloud masking effects removed, partitioned among changes in cloud types and gross cloud properties. Upon CO2 quadrupling, clouds exhibit a rapid reduction in fractional coverage, cloud-top pressure, and optical depth, with each contributing equally to a 1.1 W m−2 net cloud radiative adjustment, primarily from shortwave radiation. Rapid reductions in midlevel clouds and optically thick clouds are important in reducing planetary albedo in every model. As the planet warms, clouds become fewer, higher, and thicker, and global mean net cloud feedback is positive in all but one model and results primarily from increased trapping of longwave radiation. As was true for earlier models, high cloud changes are the largest contributor to intermodel spread in longwave and shortwave cloud feedbacks, but low cloud changes are the largest contributor to the mean and spread in net cloud feedback. The importance of the negative optical depth feedback relative to the amount feedback at high latitudes is even more marked than in earlier models. The authors show that the negative longwave cloud adjustment inferred in previous studies is primarily caused by a 1.3 W m−2 cloud masking of CO2 forcing. Properly accounting for cloud masking increases net cloud feedback by 0.3 W m−2 K−1, whereas accounting for rapid adjustments reduces by 0.14 W m−2 K−1 the ensemble mean net cloud feedback through a combination of smaller positive cloud amount and altitude feedbacks and larger negative optical depth feedbacks.
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Wang, Pin, i Hai Ping Huang. "On the W&R and RSI Expert Systems of Securities Software". Applied Mechanics and Materials 433-435 (październik 2013): 1685–88. http://dx.doi.org/10.4028/www.scientific.net/amm.433-435.1685.
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Using the method of statistical experiment and based on real and open data of securities, the research conducted a test to the W&R and RSI expert system of securities trading software. Taking annual net profit margin, rate of return, and win rate as the management objectives, the research compared and analyzed the two similar reversal trend indicators on the basis of mathematic statistics theories, and achieved results that the annual rate of return and net profit margin of the RSI expert system are superior to that of the W&R expert system for 4.72 times, and that the annual number of trades of RSI is superior to that of W&R for 0.893 times.
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Parmar, Ambika, Tina Jiao i Kelvin K. Chan. "Drug funding price negotiations: Towards achieving a balance between individual and population gains in health benefits." Journal of Clinical Oncology 37, nr 15_suppl (20.05.2019): 6641. http://dx.doi.org/10.1200/jco.2019.37.15_suppl.6641.
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6641 Background: Drug price negotiation to lower cost to a cost-effectiveness threshold (λ) is a recognized approach to improve health care opportunities for the greater benefit of the population. Critics have raised concerns for this approach given the additional time required and speculated loss of quality-adjusted life-years (QALY) for patients. The current study aimed to quantify the incremental net health benefit (INHB) of publicly funded oncology drugs, if funding occurred at list prices without (w/o) negotiations. Methods: Pan-Canadian Oncology Drug Review submissions were reviewed to identify funded drugs with unique indications. For included drug indications economic guidance panel (EGP) reports were reviewed for incremental costs (ΔC) and ΔQALY from manufacturer’s base case cost-effectiveness analyses, EGP lower (LL) and upper limit (UL) re-analyzed estimates (based on list prices). Number of new cases in Ontario (most populous province in Canada) per indication (2017-18) was obtained from provincial databases. Annual QALY gain for each indication was determined by: (ΔQALY×cases). Provincial QALY gain/loss w/o price negotiations to reference λ was estimated by: (INHB= [ΔQALY− (ΔC/λ)] ×cases). Incremental net monetary benefit demonstrated annual monetary gain/loss w/o price negotiations to reference λ: (INMB= [(ΔQALY×λ) −ΔC] ×cases). Results: 34 drug indications including 4,629 new cases were identified. Annual QALY gain for funded indications using manufacturer, LL and UL estimates was 1,851, 1,617 and 1,301, respectively. At reference λ CAD$100,000/QALY, funding w/o negotiations resulted in loss of 2,176, 2,368, 2,451 QALY, representing budgetary diversions away from other health care interventions. This would result in a provincial net annual loss of 325, 751 and 1,150 QALY, respectively. INMB demonstrated provincial net monetary loss of CAD$32,472,389, $75,113,684 and $115,022,331, respectively. Conclusions: Despite an annual gain in QALY for funded drug indications, a net provincial loss in QALY w/o price negotiations was demonstrated. Thus, supportive evidence exists for drug price negotiations towards the promotion of health benefits for the population.
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Liang, Liming, Zhimin Lan, Wen Xiong i Xiaoqi Sheng. "Retinal Vessel Segmentation Based on W-Net Conditional Generative Adversarial Nets". Journal of Medical Imaging and Health Informatics 11, nr 7 (1.07.2021): 2016–24. http://dx.doi.org/10.1166/jmihi.2021.3633.
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Accurate extraction of retinal vessels is one important factor to computer-aided diagnosis for ophthalmologic diseases. Due to the low sensitivity and insufficient segmentation of tiny blood vessels within the existing segmentation algorithms, a novel retinal vessel segmentation algorithm is proposed, and its basis is on conditional generative adversarial nets, using W-net as generator. More specifically, firstly, the U-net is expanded to W-net through the skip connection, as the U-net is beneficial to the microvascular information transmission in the skip connection layer, then the network convergence is accelerated and the parameter utilization is improved. Secondly, the standard convolutions are replaced by the depth-wise separable convolutions, thus expanding the network and reducing the number of the parameters. Thirdly, the residual blocks are employed to mitigate the gradient disappearance and the explosion. Fourthly, during the proposed algorithm, each skip connection follows Squeeze-and-Excitation blocks so that the shallow features and deep features can be effectively fused through learning the interdependence of feature channel. Generally, the loss function of the conditional generative adversarial nets is modified to make the overall segmentation performance be optimal, while having strong global penalty ability in the whole game learning model. Finally, one experiment is carried out on the DRIVE dataset with image enhancement and data expansion. From the experiment results, the segmentation sensitivity reaches 87.18%, further the specificity, accuracy and AUC are 98.19%, 96.95% and 98.42% respectively, which show the overall performance and sensitivity are better than the existing algorithms.
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Herd, RM, VH Oddy i GJ Lee. "Effect of divergent selection for weaning weight on liveweight and wool growth responses to feed intake in Merino ewes". Australian Journal of Experimental Agriculture 33, nr 6 (1993): 699. http://dx.doi.org/10.1071/ea9930699.
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During a 6-week experiment, the feed requirements for maintenance of liveweight (LW) by adult Merino ewes were measured in 2 flocks selected over 32 years for divergent weaning weight. Also examined were the net efficiency of LW gain and wool growth in response to change in feed intake, and the ability to digest dietary organic matter. Ewes selected for high weaning weight (W+) were 31% heavier than those selected for low weaning weight (W-) at the start of the experiment. To maintain LW, W+ ewes ate 24% more digestible organic matter (DOM) per day than W- ewes. There were no differences (P>0.2) in the net efficiency of feed use for LW gain. The W+ ewes digested more (P<0.01) dietary organic matter, by 1.8 percentage units, than W- ewes and, consequently, required only 22% more dry feed to maintain their heavier LW. Ewes from the 2 flocks did not differ (P>0.4) in the amount of wool grown, and as W+ ewes were larger, they produced less (P<0.01) wool per kg LW for the same DOM intake.
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Loeb, Norman G., Bruce A. Wielicki, David R. Doelling, G. Louis Smith, Dennis F. Keyes, Seiji Kato, Natividad Manalo-Smith i Takmeng Wong. "Toward Optimal Closure of the Earth's Top-of-Atmosphere Radiation Budget". Journal of Climate 22, nr 3 (1.02.2009): 748–66. http://dx.doi.org/10.1175/2008jcli2637.1.
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Abstract Despite recent improvements in satellite instrument calibration and the algorithms used to determine reflected solar (SW) and emitted thermal (LW) top-of-atmosphere (TOA) radiative fluxes, a sizeable imbalance persists in the average global net radiation at the TOA from satellite observations. This imbalance is problematic in applications that use earth radiation budget (ERB) data for climate model evaluation, estimate the earth’s annual global mean energy budget, and in studies that infer meridional heat transports. This study provides a detailed error analysis of TOA fluxes based on the latest generation of Clouds and the Earth’s Radiant Energy System (CERES) gridded monthly mean data products [the monthly TOA/surface averages geostationary (SRBAVG-GEO)] and uses an objective constrainment algorithm to adjust SW and LW TOA fluxes within their range of uncertainty to remove the inconsistency between average global net TOA flux and heat storage in the earth–atmosphere system. The 5-yr global mean CERES net flux from the standard CERES product is 6.5 W m−2, much larger than the best estimate of 0.85 W m−2 based on observed ocean heat content data and model simulations. The major sources of uncertainty in the CERES estimate are from instrument calibration (4.2 W m−2) and the assumed value for total solar irradiance (1 W m−2). After adjustment, the global mean CERES SW TOA flux is 99.5 W m−2, corresponding to an albedo of 0.293, and the global mean LW TOA flux is 239.6 W m−2. These values differ markedly from previously published adjusted global means based on the ERB Experiment in which the global mean SW TOA flux is 107 W m−2 and the LW TOA flux is 234 W m−2.
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Shepherd, Julian. "Brethren of the Net: American Entomology, 1840-1880.W. Conner Sorensen". Quarterly Review of Biology 71, nr 4 (grudzień 1996): 558. http://dx.doi.org/10.1086/419560.
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Fitzgerald, Deborah. "Brethren of the Net: American Entomology, 1840-1880. W. Conner Sorensen". Isis 87, nr 3 (wrzesień 1996): 563–64. http://dx.doi.org/10.1086/357626.
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Cheng, L., J. Zhu i R. L. Sriver. "Global representation of tropical cyclone-induced ocean thermal changes using Argo data – Part 2: Estimating air–sea heat fluxes and ocean heat content changes". Ocean Science Discussions 11, nr 6 (12.12.2014): 2907–37. http://dx.doi.org/10.5194/osd-11-2907-2014.
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Abstract. We use Argo temperature data to examine changes in ocean heat content (OHC) and air–sea heat fluxes induced by tropical cyclones (TC)s on a global scale. A footprint technique that analyzes the vertical structure of cross-track thermal responses along all storm tracks during the period 2004–2012 is utilized (see part I). We find that TCs are responsible for 1.87 PW (11.05 W m−2 when averaging over the global ocean basin) of heat transfer annually from the global ocean to the atmosphere during storm passage (0–3 days) on a global scale. Of this total, 1.05 ± 0.20 PW (4.80 ± 0.85 W m−2) is caused by Tropical storms/Tropical depressions (TS/TD) and 0.82 ± 0.21 PW (6.25 ± 1.5 W m−2) is caused by hurricanes. Our findings indicate that ocean heat loss by TCs may be a substantial missing piece of the global ocean heat budget. Net changes in OHC after storm passage is estimated by analyzing the temperature anomalies during wake recovery following storm events (4–20 days after storm passage) relative to pre-storm conditions. Results indicate the global ocean experiences a 0.75 ± 0.25 PW (5.98 ± 2.1W m−2) net heat gain annually for hurricanes. In contrast, under TS/TD conditions, ocean experiences 0.41 ± 0.21 PW (1.90 ± 0.96 W m−2) net ocean heat loss, suggesting the overall oceanic thermal response is particularly sensitive to the intensity of the event. The net ocean heat uptake caused by all storms is 0.34 PW.
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Cui, Yaoping, Michael E. Meadows, Nan Li, Yiming Fu, Guosong Zhao i Jinwei Dong. "Land Cover Change Intensifies Actual and Potential Radiative Forcing through CO2 in South and Southeast Asia from 1992 to 2015". International Journal of Environmental Research and Public Health 16, nr 14 (11.07.2019): 2460. http://dx.doi.org/10.3390/ijerph16142460.
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Land cover change (LCC) and its impact on CO2 sequestration and radiative forcing (RF) could dramatically affect climate change, but there has been little effort to address this issue in South and Southeast Asia over a long period of time using actual land cover information. In this study, annual land cover data from 1992 to 2015 were used to assess the CO2 flux and corresponding RF due to LCC in South and Southeast Asia. The results showed that 553.2 × 103 km2 of the region experienced LCC during this period, mostly due to land reclamation, urban expansion, and deforestation. These LCC caused a marked net decrease in net ecosystem productivity (NEP) as a composite of the various land cover categories during the whole study period, especially since 2001. The CO2 sequestration was 2160 TgCO2 during the early 1990s however cumulative sequestration decreased by 414.95 TgCO2 by 2015. Correspondingly, the cooling effect of NEP, i.e. the total actual RF, was −0.366 W m−2 in South and Southeast Asia between 1992 and 2015. However, the potential RF of the cumulatively reduced NEP due to LCC relative to the 1990s resulted in a warming effect of 2.33 × 10−3 W m−2 in 2015. Our study provides an applicable framework to accurately assess the potential effect of large-scale LCC on climate.
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Liu, Chunlei, Richard P. Allan, Michael Mayer, Patrick Hyder, Damien Desbruyères, Lijing Cheng, Jianjun Xu, Feng Xu i Yu Zhang. "Variability in the global energy budget and transports 1985–2017". Climate Dynamics 55, nr 11-12 (17.09.2020): 3381–96. http://dx.doi.org/10.1007/s00382-020-05451-8.
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Abstract The study of energy flows in the Earth system is essential for understanding current climate change. To understand how energy is accumulating and being distributed within the climate system, an updated reconstruction of energy fluxes at the top of atmosphere, surface and within the atmosphere derived from observations is presented. New satellite and ocean data are combined with an improved methodology to quantify recent variability in meridional and ocean to land heat transports since 1985. A global top of atmosphere net imbalance is found to increase from 0.10 ± 0.61 W m−2 over 1985–1999 to 0.62 ± 0.1 W m−2 over 2000–2016, and the uncertainty of ± 0.61 W m−2 is related to the Argo ocean heat content changes (± 0.1 W m−2) and an additional uncertainty applying prior to 2000 relating to homogeneity adjustments. The net top of atmosphere radiative flux imbalance is dominated by the southern hemisphere (0.36 ± 0.04 PW, about 1.41 ± 0.16 W m−2) with an even larger surface net flux into the southern hemisphere ocean (0.79 ± 0.16 PW, about 3.1 ± 0.6 W m−2) over 2006–2013. In the northern hemisphere the surface net flux is of opposite sign and directed from the ocean toward the atmosphere (0.44 ± 0.16 PW, about 1.7 ± 0.6 W m−2). The sea ice melting and freezing are accounted for in the estimation of surface heat flux into the ocean. The northward oceanic heat transports are inferred from the derived surface fluxes and estimates of ocean heat accumulation. The derived cross-equatorial oceanic heat transport of 0.50 PW is higher than most previous studies, and the derived mean meridional transport of 1.23 PW at 26° N is very close to 1.22 PW from RAPID observation. The surface flux contribution dominates the magnitude of the oceanic transport, but the integrated ocean heat storage controls the interannual variability. Poleward heat transport by the atmosphere at 30° N is found to increase after 2000 (0.17 PW decade−1). The multiannual mean (2006–2013) transport of energy by the atmosphere from ocean to land is estimated as 2.65 PW, and is closely related to the ENSO variability.
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Qiu, Yu Jun, Qiang Wang i Fang Chao Hu. "Shouxian Aerosol Radiative Properties Measured by DOE AMF and Compared with CERES-MODIS". Advanced Materials Research 518-523 (maj 2012): 1973–76. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.1973.
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The U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) program held its first mobile facility (AMF) field campaigns in Shouxian in eastern China. Based on the AMF data, we studied the radiative properties of aerosols in late autumn and early winter. The results show that aerosols and clouds decreased the surface total radiation flux (RF) by 27.5% and the shortwave (SW) RF by 30.8%. The aerosol radiative effect (ARE) in late autumn and early winter calculated is about -24.9 W/m2. In addition, we compared the AMF data with MODIS datasets in a 1×1 degree box. The net SW errors of Terra and Aqua were 97.4 and 30.0 w/m2. The net LW errors were 17.4 W/m2and 21.4 W/m2, respectively. The differences of the errors between Terra and Aqua were caused by the different zenith angles and the different atmospheric aerosol and vapor backgrounds during the satellite overpasses.
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Ebell, Kerstin, Tatiana Nomokonova, Marion Maturilli i Christoph Ritter. "Radiative Effect of Clouds at Ny-Ålesund, Svalbard, as Inferred from Ground-Based Remote Sensing Observations". Journal of Applied Meteorology and Climatology 59, nr 1 (styczeń 2020): 3–22. http://dx.doi.org/10.1175/jamc-d-19-0080.1.
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AbstractFor the first time, the cloud radiative effect (CRE) has been characterized for the Arctic site Ny-Ålesund, Svalbard, Norway, including more than 2 years of data (June 2016–September 2018). The cloud radiative effect, that is, the difference between the all-sky and equivalent clear-sky net radiative fluxes, has been derived based on a combination of ground-based remote sensing observations of cloud properties and the application of broadband radiative transfer simulations. The simulated fluxes have been evaluated in terms of a radiative closure study. Good agreement with observed surface net shortwave (SW) and longwave (LW) fluxes has been found, with small biases for clear-sky (SW: 3.8 W m−2; LW: −4.9 W m−2) and all-sky (SW: −5.4 W m−2; LW: −0.2 W m−2) situations. For monthly averages, uncertainties in the CRE are estimated to be small (~2 W m−2). At Ny-Ålesund, the monthly net surface CRE is positive from September to April/May and negative in summer. The annual surface warming effect by clouds is 11.1 W m−2. The longwave surface CRE of liquid-containing cloud is mainly driven by liquid water path (LWP) with an asymptote value of 75 W m−2 for large LWP values. The shortwave surface CRE can largely be explained by LWP, solar zenith angle, and surface albedo. Liquid-containing clouds (LWP > 5 g m−2) clearly contribute most to the shortwave surface CRE (70%–98%) and, from late spring to autumn, also to the longwave surface CRE (up to 95%). Only in winter are ice clouds (IWP > 0 g m−2; LWP < 5 g m−2) equally important or even dominating the signal in the longwave surface CRE.
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Purnomo, Erry, A. S. Black i M. K. Conyers. "The distribution of net nitrogen mineralisation within surface soil. 2. Factors influencing the distribution of net N mineralisation". Soil Research 38, nr 3 (2000): 643. http://dx.doi.org/10.1071/sr99059.
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This investigation examined the magnitude of gradients in net nitrogen (N) mineralisation through the surface 20 cm of soils used for cropping, and factors influencing these gradients. Soils used were W (Red Kandosol) from a previous field study, CT (conventional tillage) and DD (direct drilled) from a long-term rotation experiment on a Red Kandosol, and YS (Yellow Sodosol) from under wheat established by reduced tillage. Soil was collected in 2-cm intervals to a depth of 10 cm and at 5-cm intervals between depths of 10 and 20 cm. All depths were used from soil W but only depths of 0–2, 8–10, and 15–20 cm were used for the remaining soils. Soils were incubated for 0, 2, 4, 8, and 16 weeks under controlled conditions (soil water, 80% of water-holding capacity; temperature, 20˚C; aeration, 1 h/week). Net N mineralisation and carbon dioxide (CO2) evolution were measured. Heterotrophic activity as measured by CO2 evolution decreased with depth but was still evident in soil from below 10 cm. This activity was strongly correlated with the concentration of organic carbon (C) (r = 0.88, P < 0.05) and soil pH (r = 0.80, P < 0.05). The percentage of organic C released as CO2 was highly correlated with pH (r = 0.86, P < 0.05), implying that, when sampled at an appropriate scale, acidity limits heterotrophic activity. Net N mineralisation decreased with depth in all soils. In soil W, 59% of net N mineralised originated from 0 to 2 cm, 87% was from the surface 6 cm, and only 1% was from below 10 cm. This was similar to the distribution of net N mineralisation found in the field experiment reported in the previous paper. Net N mineralisation was correlated with CO2 evolution (r = 0.97, P < 0.01) and pH (r = 0.73, P < 0.05). The C : N ratio increased from 18 in the surface 6 cm to 27 between 10 and 20 cm. The lack of net N mineralisation below 10 cm was attributed to this increase in the C : N ratio. This is the first observation of gradients in net N mineralisation with depth at this scale in different tillage systems.
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Kato, Seiji, Fred G. Rose, David A. Rutan, Tyler J. Thorsen, Norman G. Loeb, David R. Doelling, Xianglei Huang, William L. Smith, Wenying Su i Seung-Hee Ham. "Surface Irradiances of Edition 4.0 Clouds and the Earth’s Radiant Energy System (CERES) Energy Balanced and Filled (EBAF) Data Product". Journal of Climate 31, nr 11 (17.05.2018): 4501–27. http://dx.doi.org/10.1175/jcli-d-17-0523.1.
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Abstract The algorithm to produce the Clouds and the Earth’s Radiant Energy System (CERES) Edition 4.0 (Ed4) Energy Balanced and Filled (EBAF)-surface data product is explained. The algorithm forces computed top-of-atmosphere (TOA) irradiances to match with Ed4 EBAF-TOA irradiances by adjusting surface, cloud, and atmospheric properties. Surface irradiances are subsequently adjusted using radiative kernels. The adjustment process is composed of two parts: bias correction and Lagrange multiplier. The bias in temperature and specific humidity between 200 and 500 hPa used for the irradiance computation is corrected based on observations by Atmospheric Infrared Sounder (AIRS). Similarly, the bias in the cloud fraction is corrected based on observations by Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) and CloudSat. Remaining errors in surface, cloud, and atmospheric properties are corrected in the Lagrange multiplier process. Ed4 global annual mean (January 2005 through December 2014) surface net shortwave (SW) and longwave (LW) irradiances increase by 1.3 W m−2 and decrease by 0.2 W m−2, respectively, compared to EBAF Edition 2.8 (Ed2.8) counterparts (the previous version), resulting in an increase in net SW + LW surface irradiance of 1.1 W m−2. The uncertainty in surface irradiances over ocean, land, and polar regions at various spatial scales are estimated. The uncertainties in all-sky global annual mean upward and downward shortwave irradiance are 3 and 4 W m−2, respectively, and the uncertainties in upward and downward longwave irradiance are 3 and 6 W m−2, respectively. With an assumption of all errors being independent, the uncertainty in the global annual mean surface LW + SW net irradiance is 8 W m−2.
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Yang, Ningjing, Qingyuan Chen, Yafang Xu, Jinlong Luo, Hai Yang i Guojun Jin. "Strain-modulated electronic transport in two-dimensional carbon allotropes". AIP Advances 12, nr 4 (1.04.2022): 045102. http://dx.doi.org/10.1063/5.0088033.
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Carbon has various allotropes showing rich physical properties. Here, we take net C and net W as the research objects. They are all composed of carbonic squares C4, hexagons C6, and octagons C8, but with different compositions. Using the combination of density functional theory calculations and non-equilibrium Green’s function method, we study the significant changes in electronic structures and transport behaviors in response to external strain. For net C, tunable negative differential resistance (NDR) is observed. The NDR bias region can be moved and widened, while its peak-to-valley ratio can be increased from the original 1.14 to largest 2.67. The electrical conductivity of net W exhibits a very good linear relationship within a large strain range from −4% to +4%, and it can be increased to 219.9%. By analyzing their band structures, the effective regulations of strain on both the NDR and linear conductivity are explained. These results show not only the differences from deformation for various carbon rings under strain but also a certain guiding significance for applications in electronic devices.
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Grandey, Benjamin S., Hsiang-He Lee i Chien Wang. "Radiative effects of interannually varying vs. interannually invariant aerosol emissions from fires". Atmospheric Chemistry and Physics 16, nr 22 (23.11.2016): 14495–513. http://dx.doi.org/10.5194/acp-16-14495-2016.
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Abstract. Open-burning fires play an important role in the earth's climate system. In addition to contributing a substantial fraction of global emissions of carbon dioxide, they are a major source of atmospheric aerosols containing organic carbon, black carbon, and sulfate. These “fire aerosols” can influence the climate via direct and indirect radiative effects. In this study, we investigate these radiative effects and the hydrological fast response using the Community Atmosphere Model version 5 (CAM5). Emissions of fire aerosols exert a global mean net radiative effect of −1.0 W m−2, dominated by the cloud shortwave response to organic carbon aerosol. The net radiative effect is particularly strong over boreal regions. Conventionally, many climate modelling studies have used an interannually invariant monthly climatology of emissions of fire aerosols. However, by comparing simulations using interannually varying emissions vs. interannually invariant emissions, we find that ignoring the interannual variability of the emissions can lead to systematic overestimation of the strength of the net radiative effect of the fire aerosols. Globally, the overestimation is +23 % (−0.2 W m−2). Regionally, the overestimation can be substantially larger. For example, over Australia and New Zealand the overestimation is +58 % (−1.2 W m−2), while over Boreal Asia the overestimation is +43 % (−1.9 W m−2). The systematic overestimation of the net radiative effect of the fire aerosols is likely due to the non-linear influence of aerosols on clouds. However, ignoring interannual variability in the emissions does not appear to significantly impact the hydrological fast response. In order to improve understanding of the climate system, we need to take into account the interannual variability of aerosol emissions.