We present the result of a search of the Milagro sky map for spatial correlations with sources from a subset of the recent Fermi Bright Source List (BSL). The BSL consists of the 205 most significant ...sources detected above 100 MeV by the Fermi Large Area Telescope. We select sources based on their categorization in the BSL, taking all confirmed or possible Galactic sources in the field of view of Milagro. Of the 34 Fermi sources selected, 14 are observed by Milagro at a significance of 3 standard deviations or more. We conduct this search with a new analysis which employs newly optimized gamma-hadron separation and utilizes the full eight-year Milagro data set. Milagro is sensitive to gamma rays with energy from 1 to 100 TeV with a peak sensitivity from 10 to 50 TeV depending on the source spectrum and declination. These results extend the observation of these sources far above the Fermi energy band. With the new analysis and additional data, multi-TeV emission is definitively observed associated with the Fermi pulsar, J2229.0+6114, in the Boomerang pulsar wind nebula (PWN). Furthermore, an extended region of multi-TeV emission is associated with the Fermi pulsar, J0634.0+1745, the Geminga pulsar.
The electrochemical synthesis of ammonia from N2 and H+ ions was studied over a Ni–BZCY72 cermet, with and without H2 in the gas phase. The effect of temperature, cathode chamber feed composition and ...applied voltage was explored in detail. Without H2 in the cathode chamber, the highest rate was 1.7×10−9mol/s·cm2 at 620°C. When H2 was present in the gas phase, ammonia was synthesized electrochemically at much higher rates and Faradaic efficiencies. The maximum net electrochemical synthesis rate of 4.1×10−9mol/s·cm2 was obtained with ΡΗ2/ΡΝ2=1 at 620°C, corresponding to a 140% enhancement of the open circuit rate at the cost of electrical energy. In both cases these high rates were accompanied by a low Faradaic efficiency, pointing to the need for catalyst improvement.
•Electrochemical synthesis of ammonia is enhanced by co-feeding H2 to the cathode.•A high open circuit rate can be electrochemically enhanced by up to 140%.•Electrochemical synthesis is optimal at equimolar and not at stoichiometric feed.•High current densities can have a negative effect on electrochemical synthesis.
•Vaccination programs against Ovine Respiratory Complex in lambs should be accompanied by non-specific preventive measures.•There are vaccines for sheep licensed only against Mannheimia haemolytica, ...Bibersteinia trehalosi and Pasteurella multocida.•According to antigens contained in the vaccines, they can be divided into outer membrane protein, leucotoxoid or iron regulated protein vaccines.•The lambs should be vaccinated during the first week of life followed by a booster dose three weeks apart.
Vaccination programs against Ovine Respiratory Complex (ORC) in lambs should be accompanied by non-specific preventive measure, e.g., establishment of proper management and husbandry conditions. Implementing a vaccination plan against ORC requires: involvement of all farm staff, recording data, a positive cost:benefit analysis and continuous monitoring over time. Licensed vaccines for sheep are only against Mannheimia haemolytica (MH), Bibersteinia trehalosi (BT) and Pasteurella multocida (PM). According to the antigens contained in the MH vaccines, these can be divided into outer membrane protein vaccines (OmpA), leucotoxoid vaccines (LKT) and iron regulated protein vaccines (IROMP). Each serotype of MH or BT presents differences in these three antigens, although in the case of IROMP, there is an effective cross protection among them. In addition, strains of bovine origin do not protect sheep and vice versa. For PM, vaccines containing bacteria grown in iron restricted conditions give better results. The lambs should be vaccinated during the first week of life followed by a booster dose three weeks apart. The best results are obtained with LKT vaccines, when the serotype that is present in the farm is included in the vaccine, or with IROMP, which can be applied in any situation.
Serum neurofilament light chain (sNfL) and optical coherence tomography (OCT)-derived retinal measures (including peripapillary retinal nerve fiber layer pRNFL and macular ganglion cell layer/inner ...plexiform layer GCIPL thickness) have been proposed as biomarkers of neurodegeneration in multiple sclerosis (MS). However, studies evaluating the associations between sNfL and OCT-derived retinal measures in MS are limited.
In this retrospective analysis of a longitudinal, observational, single-center cohort study, sNfL levels were measured in people with MS and healthy controls (HCs) using single molecule array. Participants with MS were followed with serial OCT for a median follow-up of 4.5 years. Eyes with optic neuritis (ON) within 6 months of baseline OCT or ON during follow-up were excluded. Age-normative cutoffs of sNfL were derived using the HC data, and MS participants with sNfL greater than the 97.5th percentile for age were classified as having elevated sNfL (sNfL-E). Analyses were performed with mixed-effects linear regression models and adjusted for age, sex, race, and history of ON.
A total of 130 HCs (age: 42.4 ± 14.2 years; 62% female) and 403 people with MS (age: 43.1 ± 12.0 years; 78% female) were included. Elevated sNfL levels were present at baseline in 80 participants with MS (19.9%). At baseline, sNfL-E participants had modestly lower pRNFL (-3.03 ± 1.50 μm;
= 0.044) and GCIPL thickness (-2.74 ± 1.02 μm;
= 0.007). As compared with those with sNfL within the reference range, eyes from NfL-E participants exhibited faster longitudinal thinning of the pRNFL (45% faster; -0.74 vs -0.51 μm/y;
= 0.015) and GCIPL (25% faster; -0.35 vs -0.28 μm/y;
= 0.021). Significant differences in rates of pRNFL and GCIPL thinning between sNfL groups were found only in those with relapsing-remitting MS but not progressive MS.
Elevated baseline sNfL is associated with accelerated rates of retinal neuroaxonal loss in relapsing-remitting MS, independent of overt ON, but may be less reflective of retinal neurodegeneration in progressive MS.
Highlights: • AI in weed management potentials for transforming agricultural ecosystems. • AI influence in economic, social, technological, and environmental dimensions. • AI's role in enhancing food ...safety by reducing pesticides residues. • Digital literacy as a crucial enabler empowering stakeholders to use AI effectively.Abstract: In the face of increasing agricultural demands and environmental concerns, the effective management of weeds presents a pressing challenge in modern agriculture. Weeds not only compete with crops for resources but also pose threats to food safety and agricultural sustainability through the indiscriminate use of herbicides, which can lead to environmental contamination and herbicide-resistant weed populations. Artificial Intelligence (AI) has ushered in a paradigm shift in agriculture, particularly in the domain of weed management. AI's utilization in this domain extends beyond mere innovation, offering precise and eco-friendly solutions for the identification and control of weeds, thereby addressing critical agricultural challenges. This article aims to examine the application of AI in weed management in the context of weed detection and the increasing impact of deep learning techniques in the agricultural sector. Through an assessment of research articles, this study identifies critical factors influencing the adoption and implementation of AI in weed management. These criteria encompass factors of AI adoption (food safety, increased effectiveness, and eco-friendliness through herbicides reduction), AI implementation factors (capture technology, training datasets, AI models, and outcomes and accuracy), ancillary technologies (IoT, UAV, field robots, and herbicides), and the related impact of AI methods adoption (economic, social, technological, and environmental). Of the 5821 documents found, 99 full-text articles were assessed, and 68 were included in this study. The review highlights AI's role in enhancing food safety by reducing herbicide residues, increasing effectiveness in weed control strategies, and promoting eco-friendliness through judicious herbicide use. It underscores the importance of capture technology, training datasets, AI models, and accuracy metrics in AI implementation, emphasizing their synergy in revolutionizing weed management practices. Ancillary technologies, such as IoT, UAVs, field robots, and AI-enhanced herbicides, complement AI's capabilities, offering holistic and data-driven approaches to weed control. Additionally, the adoption of AI methods influences economic, social, technological, and environmental dimensions of agriculture. Last but not least, digital literacy emerges as a crucial enabler, empowering stakeholders to navigate AI technologies effectively and contribute to the sustainable transformation of weed management practices in agriculture.
•Thermal-metallurgical-mechanical model for electron beam (EB) welding in SA508 Gr.4N low-alloy steel plate has been developed and validated.•Inter-part gapping occurs when EB weld centre plane is ...not restrained before welding, but the gapping distortion can be mitigated by tack-weld restraint.•High tensile stress is induced at stop-end tack weld during welding, which can be effectively reduced by increasing tack-weld extent.•Tack-weld restraint hardly affects final weld residual stress which exhibits steep gradient across heat affected zone (HAZ) boundary.•Weld-induced martensitic transformation promotes compression and suppresses tension in EB weld and HAZ, and peak tensile residual stress is concentrated in base material immediately outside HAZ.
Electron beam (EB) welding has a low tolerance to inter-part gapping distortion and can generate complicated stresses, which pose challenges to weld quality and integrity. This study investigates welding distortion and stresses in an EB welded plate made from SA508 Grade 4N low-alloy steel. A thermal-metallurgical-mechanical model was developed to predict the temperature, micro-constituents, hardness, distortion and stresses in the EB weldment; the predictions are in good agreement with experimental results. Different restraint conditions on the weld plane were modelled to examine their effects on distortion and stresses. If welding is performed with no restraint, inter-part gapping develops ahead of the beam position that could exceed the tolerance for a sound weld. In contrast, tack welds at the plate ends significantly reduce this gapping, but induce additional tensile stress at the stop-end tack weld. This stress is particularly high as the beam approaches the tack weld. Increasing the extent of the tack weld reduces the tensile stress, while increasing number of distantly distributed narrow tack welds does not help. A full through-length restraint eliminates the opening gap and minimises the development of tensile stresses ahead of the beam that could potentially break the restraint. The applied restraint on the weld plane has little effect on the final residual stress field, since this field mostly develops during cooling after the EB weld is complete. The weld-induced martensitic transformation suppressed tension or promoted compression in the EB weld and heat affected zone (HAZ). A steep gradient of residual stress exists, with high tensile stress concentrated in a narrow region immediately outside the HAZ.
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Background:
Prior studies have suggested that subclinical retinal abnormalities may be present in aquaporin-4 immunoglobulin G (AQP4-IgG) seropositive neuromyelitis optica spectrum disorder (NMOSD), ...in the absence of a clinical history of optic neuritis (ON).
Objective:
Our aim was to compare retinal layer thicknesses at the fovea and surrounding macula between AQP4-IgG+ NMOSD eyes without a history of ON (AQP4-nonON) and healthy controls (HC).
Methods:
In this single-center cross-sectional study, 83 AQP4-nonON and 154 HC eyes were studied with spectral-domain optical coherence tomography (OCT).
Results:
Total foveal thickness did not differ between AQP4-nonON and HC eyes. AQP4-nonON eyes exhibited lower outer nuclear layer (ONL) and inner photoreceptor segment (IS) thickness at the fovea (ONL: −4.01 ± 2.03 μm, p = 0.049; IS: −0.32 ± 0.14 μm, p = 0.029) and surrounding macula (ONL: −1.98 ± 0.95 μm, p = 0.037; IS: −0.16 ± 0.07 μm, p = 0.023), compared to HC. Macular retinal nerve fiber layer (RNFL: −1.34 ± 0.51 μm, p = 0.009) and ganglion cell + inner plexiform layer (GCIPL: −2.44 ± 0.93 μm, p = 0.009) thicknesses were also lower in AQP4-nonON compared to HC eyes. Results were similar in sensitivity analyses restricted to AQP4-IgG+ patients who had never experienced ON in either eye.
Conclusions:
AQP4-nonON eyes exhibit evidence of subclinical retinal ganglion cell neuronal and axonal loss, as well as structural evidence of photoreceptor layer involvement. These findings support that subclinical anterior visual pathway involvement may occur in AQP4-IgG+ NMOSD.
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•Modest variations in SA508 steel chemistry have a marked impact on EB weld residual stresses.•Significant stresses remain after an ASME-compliant post-weld heat ...treatment.•Single-pass EB welds are likely to have thickness-dependent residual stress distributions.•Phase transformation kinetics must be incorporated into models for stress development.
Reduced-pressure electron beam (EB) plate butt welds were manufactured in two low-alloy pressure-vessel steels, SA508 Gr 3 Cl 1 and SA508 Gr 2, at two thicknesses in both steels, 30 mm and 130 mm. Transient temperatures during welding were recorded using thermocouple arrays. Residual stresses in the as-welded condition and after post-weld heat treatment were measured using diverse methods: neutron diffraction and the contour method at 30 mm thickness; and deep hole drilling and the contour method at 130 mm. Incremental centre hole drilling measurements were performed at 130 mm thickness to better understand near-surface stresses. Weld and heat-affected zone microstructures and microconstituents were evaluated using a combination of hardness mapping, optical microscopy and electron microscopy. The as-welded residual stresses exhibit the characteristic M-shaped distribution for hardenable steels, reaching 500–600 MPa in tension in both steels at both thicknesses. However, the modest changes to the chemical composition and the change in plate thickness both significantly influenced microstructures, mechanical properties and residual stress distributions. These sensitivities underline the need for physically faithful models. This extensive characterisation study enables the development and validation of models that predict the development of microstructures and residual stresses in EB welds in low alloy pressure vessel steels.
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