2,158 research outputs found
Economic Modeling of Hungarian Farms Incorporating Nature Conservation
Hungary's imminent entrance into the EU calls for a farm-level financial support system aiming at combining agricultural production with nature conservation targets. Within the Hungarian National Agri-environmental Programme (NAEP) for the Environmentally Sensitive Areas, a payment system was developed. For each individual region the amount of support for every environmentally friendly farming prescription package (tier) was established using the support calculation methodology of the EU. The purpose of this paper is to analyse the impact of the packages on the income of an individual mixed farm. In contrast to many other studies, in the current study the analysis was carried out with the context of the whole farm, taking into consideration the entire production structure. The amount of support which the farmer needs to sign up for a contract turned out to be quite different from the actual payments done by the Hungarian government.Farm Management, Land Economics/Use,
Anisotropic low field behavior and the observation of flux jumps in CeCoIn5
The magnetic behavior of the heavy fermion superconductor CeCoIn5 has been
investigated. The low field magnetization data show flux jumps in the mixed
state of the superconducting phase in a restricted range of temperature. These
flux jumps begin to disappear below 1.7 K, and are completely absent at 1.5 K.
The magnetization loops are asymmetric, suggesting that surface and geometrical
factors dominate the pinning in this system. The lower critical field (Hc1),
obtained from the magnetization data, shows a linear temperature dependence and
is anisotropic. The calculated penetration depth is also anisotropic, which is
consistent with the observation of an anisotropic superconducting gap in
CeCoIn5. The critical currents, determined from the high field isothermal
magnetization loops, are comparatively low (around 4000 A/cm2 at 1.6 K and 5
kOe).Comment: 4 pages 3 figure
Detection of High Energy Ionizing Radiation using Deeply Depleted Graphene-Oxide-Semiconductor Junctions
Graphene's linear bandstructure and two-dimensional density of states provide
an implicit advantage for sensing charge. Here, these advantages are leveraged
in a deeply depleted graphene-oxide-semiconductor (D2GOS) junction detector
architecture to sense carriers created by ionizing radiation. Specifically, the
room temperature response of the silicon-based D2GOS junction is analyzed
during irradiation with 20 MeV Si4+ ions. Detection was demonstrated for doses
ranging from 12-1200 ions with device functionality maintained with no
substantive degradation. To understand the device response, D2GOS pixels were
characterized post-irradiation via a combination of electrical
characterization, Raman spectroscopy, and photocurrent mapping. This combined
characterization methodology underscores the lack of discernible damage caused
by irradiation to the graphene while highlighting the nature of interactions
between the incident ions and the silicon absorber.Comment: 15 pages, 4 figure
Engineering of increased L-Threonine production in bacteria by combinatorial cloning and machine learning
The goal of this study is to develop a general strategy for bacterial engineering using an integrated synthetic biology and machine learning (ML) approach. This strategy was developed in the context of increasing L-threonine production in Escherichia coli ATCC 21277. A set of 16 genes was initially selected based on metabolic pathway relevance to threonine biosynthesis and used for combinatorial cloning to construct a set of 385 strains to generate training data (i.e., a range of L-threonine titers linked to each of the specific gene combinations). Hybrid (regression/classification) deep learning (DL) models were developed and used to predict additional gene combinations in subsequent rounds of combinatorial cloning for increased L-threonine production based on the training data. As a result, E. coli strains built after just three rounds of iterative combinatorial cloning and model prediction generated higher L-threonine titers (from 2.7 g/L to 8.4 g/L) than those of patented L-threonine strains being used as controls (4–5 g/L). Interesting combinations of genes in L-threonine production included deletions of the tdh, metL, dapA, and dhaM genes as well as overexpression of the pntAB, ppc, and aspC genes. Mechanistic analysis of the metabolic system constraints for the best performing constructs offers ways to improve the models by adjusting weights for specific gene combinations. Graph theory analysis of pairwise gene modifications and corresponding levels of L-threonine production also suggests additional rules that can be incorporated into future ML models
Heavy Ion Microbeam and Broadbeam Transients in SiGe HBTs
SiGe HBT heavy ion current transients are measured using microbeam and both high- and low-energy broadbeam sources. These new data provide detailed insight into the effects of ion range, LET, and strike location
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Simulation of neutron displacement damage in bipolar junction transistors using high-energy heavy ion beams.
Electronic components such as bipolar junction transistors (BJTs) are damaged when they are exposed to radiation and, as a result, their performance can significantly degrade. In certain environments the radiation consists of short, high flux pulses of neutrons. Electronics components have traditionally been tested against short neutron pulses in pulsed nuclear reactors. These reactors are becoming less and less available; many of them were shut down permanently in the past few years. Therefore, new methods using radiation sources other than pulsed nuclear reactors needed to be developed. Neutrons affect semiconductors such as Si by causing atomic displacements of Si atoms. The recoiled Si atom creates a collision cascade which leads to displacements in Si. Since heavy ions create similar cascades in Si we can use them to create similar damage to what neutrons create. This LDRD successfully developed a new technique using easily available particle accelerators to provide an alternative to pulsed nuclear reactors to study the displacement damage and subsequent transient annealing that occurs in various transistor devices and potentially qualify them against radiation effects caused by pulsed neutrons
Patient-Reported Toxicity and Quality-of-Life Profiles in Patients With Head and Neck Cancer Treated With Definitive Radiation Therapy or Chemoradiation
Purpose: Radiation therapy is an effective but burdensome treatment for head and neck cancer (HNC). We aimed to characterize the severity and time pattern of patient-reported symptoms and quality of life in a large cohort of patients with HNC treated with definitive radiation therapy, with or without systemic treatment. Methods and Materials: A total of 859 patients with HNC treated between 2007 and 2017 prospectively completed the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-Head and Neck Cancer module (QLQ-HN35) and Core Quality of Life Questionnaire (QLQ-C30) at regular intervals during and after treatment for up to 5 years. Patients were classified into 3 subgroups: early larynx cancer, infrahyoideal cancer, and suprahyoideal cancer. Outcome scales of both questionnaires were quantified per subgroup and time point by means of average scores and the frequency distribution of categorized severity (none, mild, moderate, and severe). Time patterns and symptom severity were characterized. Toxicity profiles were compared using linear mixed model analysis. Additional toxicity profiles based on age, human papillomavirus status, treatment modality, smoking status, tumor site, and treatment period were characterized as well. Results: The study population consisted of 157 patients with early larynx cancer, 304 with infrahyoideal cancer, and 398 with suprahyoideal cancer. The overall questionnaire response rate was 83%. Generally, the EORTC QLQ-HN35 symptoms reported showed a clear time pattern, with increasing scores during treatment followed by a gradual recovery in the first 2 years. Distinct toxicity profiles were seen across subgroups (P < .001), with generally less severe symptom scores in the early larynx subgroup. The EORTC QLQ-C30 functioning, quality-of-life, and general symptoms reported showed a less evi- dent time pattern and less pronounced differences in mean scores between subgroups, although differences were still signifi- cant (P < .001). Differences in mean scores were most pronounced for role functioning, appetite loss, fatigue, and pain. Conclusions: We established patient-reported toxicity and quality-of-life profiles that showed different patterns for 3 sub-groups of patients with HNC. These profiles provide detailed information on the severity and persistence of various symptoms as experienced by patients during and after definitive radiation therapy. These profiles can be used to inform treatment of future patients and may serve as a benchmark for future studies. (C) 2021 The Authors. Published by Elsevier Inc
Few multiyear precipitation-reduction experiments find a shift in the productivity-precipitation relationship
Well-defined productivity–precipitation relationships of ecosystems are needed as benchmarks for the validation of land models used for future projections. The productivity–precipitation relationship may be studied in two ways: the spatial approach relates differences in productivity to those in precipitation among sites along a precipitation gradient (the spatial fit, with a steeper slope); the temporal approach relates interannual productivity changes to variation in precipitation within sites (the temporal fits, with flatter slopes). Precipitation–reduction experiments in natural ecosystems represent a complement to the fits, because they can reduce precipitation below the natural range and are thus well suited to study potential effects of climate drying. Here, we analyse the effects of dry treatments in eleven multiyear precipitation–manipulation experiments, focusing on changes in the temporal fit. We expected that structural changes in the dry treatments would occur in some experiments, thereby reducing the intercept of the temporal fit and displacing the productivity–precipitation relationship downward the spatial fit. The majority of experiments (72%) showed that dry treatments did not alter the temporal fit. This implies that current temporal fits are to be preferred over the spatial fit to benchmark land-model projections of productivity under future climate within the precipitation ranges covered by the experiments. Moreover, in two experiments, the intercept of the temporal fit unexpectedly increased due to mechanisms that reduced either water loss or nutrient loss. The expected decrease of the intercept was observed in only one experiment, and only when distinguishing between the late and the early phases of the experiment. This implies that we currently do not know at which precipitation–reduction level or at which experimental duration structural changes will start to alter ecosystem productivity. Our study highlights the need for experiments with multiple, including more extreme, dry treatments, to identify the precipitation boundaries within which the current temporal fits remain valid
Quality of life during first-line FOLFOX4±panitumumab in RAS wild-type metastatic colorectal carcinoma : results from a randomised controlled trial
Metastatic colorectal cancer is rarely curable. Improving quality of life is therefore a key treatment goal. We report quality of life for patients with RAS wild-type metastatic colorectal cancer in the PRIME study. A randomised phase 3 open-label study of first-line panitumumab+FOLFOX4 vs FOLFOX4 enrolled adults with untreated metastatic colorectal cancer and an Eastern Cooperative Oncology Group performance status of 0-2. This analysis includes patients with wild-type RAS tumours (n=505). Quality of life (prespecified end point) was assessed using the EuroQoL 5-domain health state index and overall health rating in all patients and by early tumour shrinkage status (≥30% reduction in size by week 8; exploratory end point). Differences in quality of life were assessed using analysis of covariance and a mixed-effect piecewise linear model, and were also analysed by skin toxicity severity. There were no statistically significant differences between treatment arms from baseline to progression or to discontinuation. Grade 3+ skin toxicity was reported by 38% of patients receiving panitumumab+FOLFOX4 and 2% receiving FOLFOX4 alone. There were no significant differences in quality of life between patients with grade 0-2 skin toxicity and those with grade 3+ skin toxicity. More patients receiving panitumumab+FOLFOX4 vs FOLFOX4 had early tumour shrinkage (p<.001). In patients with tumour symptoms at baseline, there were statistically significant improvements in quality of life in those with early tumour shrinkage versus those without early tumour shrinkage. Addition of panitumumab to FOLFOX4 in first-line therapy for metastatic colorectal cancer prolongs survival and has no negative effect on overall quality of life compared with FOLFOX4 alone. Specific quality of life assessments for skin toxicity should be included in study designs to better define the direct effect of these adverse events. NCT00364013
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