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At least 19 records

Nuclear Data Sheets for A = 26

Evaluated spectroscopic data and level schemes from radioactive decay and nuclear reaction studies are presented for {sup 26}O, {sup 26}F, {sup 26}Ne, {sup 26}Na, {sup 26}Mg, {sup 26}Al, {sup 26}Si, {sup 26}P, and {sup 26}S. This evaluation for A = 26 supersedes the earlier one by P. M. Endt (1998En04) and updates for some nuclides in ENSDF. Highlights of this evaluation are the following: This evaluation includes search results for {sup 26}S nuclide and its proton–decay mode (2011Fo08). An isomeric state (2.2 ms) in {sup 26}F has been discovered by 2013Le03. The state is proposed at 643.4 keV 1 from γ–ray measurements. Internal-transition and beta-decay branches for the state are also determined. New excited levels in {sup 26}Ne have been identified from {sup 26}F β{sup −} decay (2.2 ms). For some {sup 26}Si resonance states conflicting spin-parity assignments exist in the literature. These are identified by footnotes. 2015Do07 ({sup 3}He,nγ) propose the first 0+ state above proton separation energy at an excitation energy of 5890 keV and suggested for additional independent measurements to confirm or refute the existence of 5946 keV 4. 2016Ch09 consider 5946 keV level as a distinct excited state in their reanalysis of the literature data with possible spin-parity assignment of 0+ or 4+ This evaluation also includes discovery of an isomeric state, at 164.1 keV 1, in {sup 26}P by 2014NiZZ.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

Spectroscopy and lifetime measurements near the proton drip line: P 26 , 27 , 28

We report on the observation of excited states in the neutron-deficient phosphorus isotopes 26,27,28 P via in-beam gamma-ray spectroscopy with both high-efficiency and high-resolution detector arrays. In 26 P, a previously-unobserved level has been identified at 244(3) keV, two new measurements of the astrophysically-important 3/2 + resonance in 27 P have been performed, gamma decays have been assigned to the proton-unbound levels at 2216 keV and 2483 keV in 28 P, and the gamma-ray lineshape method has been used to make the first determination of the lifetimes of the two lowest-lying excited states in 28P. The expected Thomas-Ehrman shifts were calculated and applied to levels in the mirror nuclei. The resulting level energies from this procedure were then compared with the energies of known states in 26,27,28 P.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

Environmental and cost benefits of multi‐purpose buffers in an agricultural watershed for biomass production

Abstract The cost‐benefit of riparian buffers to landowners has not been fully understood despite its ecosystem benefits. This study investigates the environmental and economic value of multi‐purpose buffers for biomass production under alternative land‐management scenarios at the watershed scale. The work incorporates the Soil and Water Assessment Tool with a field‐scale tool, the Agriculture Conservation Practice Framework, and cost‐benefit analysis. Our work took place in the agriculturally dominant Raccoon River watershed (RRW) in Iowa. The cost analysis includes implementing and harvesting the switchgrass buffers, the value of nitrogen and phosphorus fertilizer, and the forgone income of cropland to determine the net return under 12 alternative feedstock scenarios. We estimated that 14 603 Mg of nitrogen and 2563 Mg of phosphorus runoffs can be intercepted by riparian buffers in the RRW, representing a nutrient loss reduction of 11% of nitrogen and 26% of phosphorus. These nutrients are valued at $1.31 million (M) for phosphorus and $1.24 M for nitrogen as fertilizers. The trapped nutrients account for 12% of the riparian buffers’ total cost. We found that net economic returns increase with biomass market price, increase with maintenance fertilizer application, and decrease with the cropland areas that are converted to buffers. Under current land management, a biomass market price at $60 per dry ton of biomass would be economically viable at the sub‐basin level when maintenance fertilizers are applied. At $80 per dry ton, all 108 sub‐basins in the RRW would be profitable up to $517 a year. The results highlight the trade‐offs between water quality and profitability. Published 2021. This article is a U.S. Government work and is inthe public domain in the USA. Biofuels, Bioproducts and Biorefining published by Society of Industrial Chemistry and John Wiley & Sons Ltd.

09 BIOMASS FUELS↗

International Medical Graduates in Radiation Oncology: Historical Trends and Comparison With Other Medical Specialties

Purpose: This is the first National Resident Matching Program analysis evaluating historical patterns of international medical graduates (IMGs) in radiation oncology (RO) and providing comparison with American (MD) medical graduates (AMGs), osteopathic students (DOs), unfilled positions, and other specialties. Methods and Materials: National Resident Matching Program data for IMGs were available from 2003 to 2015, with limited data for other specialty matches. The following RO-specific figures were obtained per year: total positions available; total matched positions; number of unfilled positions; and number of IMG, AMG, and DO matches. In addition, the number of IMG matches and total matched positions were obtained for 19 other specialties. Fisher exact tests and χ{sup 2} tests were considered significant at α <.05. Results: From 2010 to 2015, 0.8% of RO matches were IMGs, a decline from 2.4% in 2003 to 2009 (P=.006). Proportions of DO matches during these intervals increased by 40% (from 1.0% to 1.4%), significantly lower than IMGs for 2003 to 2009 (P=.03) but not 2010 to 2015 (P=.26). From 2003 to 2015, the percentage of IMG matches, at 1.5%, was significantly lower than the percentage of unfilled seats, at 3.5% (P<.001). In comparison with other specialties (2003-2015), RO had the fewest IMG matches (1.5%), followed by otolaryngology (1.9%) and orthopedics (2.2%); specialties with the highest IMG proportions were internal medicine (37.1%), family medicine (35.7%), and neurology (31.1%). Conclusions: Presently, IMGs represent <1% of RO matches, the lowest among major specialties. There are several speculative factors associated with this low proportion. There are significantly more unfilled positions than those filled by IMGs; programs at risk of not matching could weigh the advantages and disadvantages of interviewing IMGs.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Haemorrhagic Complications and Symptomatic Venous Thromboembolism in Interventional Tumour Ablations: The Impact of Peri-interventional Thrombosis Prophylaxis

AimThe aim of this study was to assess the rates of haemorrhagic and thrombotic complications in patients undergoing interventional tumour ablation with and without peri-interventional low-molecular-weight heparin (LMWH) thrombosis prophylaxis.MethodsPatients presented with primary and secondary neoplastic lesions in the liver, lung, kidney, lymph nodes and other locations. A total of 781 tumour ablations (radiofrequency ablation, n = 112; interstitial brachytherapy, n = 669) were performed in 446 patients over 22 months; 260 were conducted under peri-interventional thrombosis prophylaxis with LMWH (H-group;) and 521 without this (NH-group, in 143 of these, LMWH was given post-interventionally).ResultsSixty-three bleeding events occurred. There were significantly more bleedings in the H-group than in the NH-group (all interventions, 11.66 and 6.26 %, p = 0.0127; liver ablations, 12.73 and 7.1 %, p = 0.0416). The rate of bleeding events Grade ≥ III in all procedures was greater by a factor of >2.6 in the H-group than in the NH-group (4.64 and 1.73 %, p = 0.0243). In liver tumour ablations, the corresponding factor was about 3.3 (5.23 and 1.54 %, p = 0.028). In uni- and multivariate analyses including covariates, the only factor constantly and significantly associated with the rate of haemorrhage events was peri-interventional LMWH prophylaxis. Only one symptomatic lung embolism occurred in the entire cohort (NH-group). The 30- and 90-day mortalities were significantly greater in the H-group than in the NH-group.ConclusionsPeri-interventional LMWH thrombosis prophylaxis should be considered with caution. The rate of clinically relevant thrombotic events was extremely low.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

The combined effects of ionizing radiation and weightlessness on calcium and phosphorus content in the mineral fraction of the calcified tissues in the rat skeleton

Phosphorus and calcium content in the ash from skeletal bones (ribs, scapula, vertebra, and crus) of 30 rats exposed to ionizing radiation (800 rads) on the flight of the Kosmos 690 biosatellite was studied. A 10 percent decrease in ash content coefficient and 29 percent decrease in phosphorus content was found immediately after the flight, and a 9 percent decrease in phosphorus content persisted after 26 days of readaptation to terrestrial conditions.

Prokhonchukov, A. A.↗

Supplemental Defatted Microalgae Nannochloropsis oceanica Affected Apparent Retention and Ileal Digestibility of Nutrients in a Corn-Soybean Meal Based Diet for Broiler Chickens

Objective: This study was to assess impacts of including 10% defatted microalgae (Nannochloropsis oceanica, 45% crude protein and 3.8% ether extract) into a corn-soybean meal basal diet for broiler chickens on apparent retention and ileal digestibility of nutrients. Procedures: Day-old hatchling Cornish Giant cockerels were divided into two groups (6 cages/group, 6 chicks/cage) and fed either the basal (control) or the microalgae-supplemented (microalgae) diet for 6 weeks. Starting week 3, the two experimental diets were mixed with 0.2% chromium oxide as an indigestible marker. Total excreta of individual cages were collected daily for 3 consecutive days during week 6. At the end of week 6, chicks were euthanized to collect ileal digesta from 1 chick/cage. Energy and concentrations of dry matter, crude protein, ether extract, minerals, and amino acids in digesta, excreta, and diets were assayed. Apparent retentions and ileal digestibilities were calculated using the direct collection and indirect indicator methods. Data were analyzed by the Student’s t-test and the significant level of difference was at p < 0.05. Results: The microalgae diet had elevated (4.2% and 8.1% by the two methods, p < 0.05) apparent retention of ether extract, but similar apparent retention and ileal digestibility of dry matter and apparent metabolizable energy, compared with the control diet. Supplemental defatted microalgae decreased (p < 0.05) the apparent retention and ileal digestibility of dietary crude protein by 13% and 13%. The supplementation also decreased (p < 0.05) ileal digestibilities and apparent retentions of multiple amino acids ranging from 0.6% to 26%. Apparent retentions of sodium and total phosphorus were decreased (p < 0.05) by 13% and 71%, respectively, by the microalgae inclusion compared with the control. Conclusion: The inclusion of 10% defatted N. oceanica in the corn-soybean meal basal diet for broiler chickens led moderate increases in apparent retention and ileal digestibility of ether extract, but decreased those of crude protein, amino acids, sodium, and phosphorus.

60 APPLIED LIFE SCIENCES↗

New 26 P( p, γ ) 27 S Thermonuclear Reaction Rate and Its Astrophysical Implications in the rp -process

Accurate nuclear reaction rates for 26 P(p, γ) 27 S are pivotal for a comprehensive understanding of the rp-process nucleosynthesis path in the region of proton-rich sulfur and phosphorus isotopes. However, large uncertainties still exist in the current rate of 26 P(p, γ) 27 S because of the lack of nuclear mass and energy level structure information for 27 S. We reevaluate this reaction rate using the experimentally constrained 27 S mass, together with the shell model predicted level structure. It is found that the 26 P(p, γ) 27 S reaction rate is dominated by a direct capture reaction mechanism despite the presence of three resonances at E = 1.104, 1.597, and 1.777 MeV above the proton threshold in 27 S. The new rate is overall smaller than the other previous rates from the Hauser–Feshbach statistical model by at least 1 order of magnitude in the temperature range of X-ray burst interest. In addition, we consistently update the photodisintegration rate using the new 27 S mass. The influence of new rates of forward and reverse reaction in the abundances of isotopes produced in the rp-process is explored by postprocessing nucleosynthesis calculations. The final abundance ratio of 27 S/ 26 P obtained using the new rates is only 10% of that from the old rate. The abundance flow calculations show that the reaction path 26 P(p, γ) 27 S(β + ,ν) 27 P is not as important as previously thought for producing 27 P. The adoption of the new reaction rates for 26 P(p, γ) 27 S only reduces the final production of aluminum by 7.1% and has no discernible impact on the yield of other elements.

79 ASTRONOMY AND ASTROPHYSICS↗

Synergistic Removal of Zinc and Copper in Greenhouse Waste Effluent by Struvite

Struvite (MgNH 4 PO 4 ·6H 2 O) can be recovered from wastewaters for mitigation of phosphorus content. However, the interaction of dissolved constituents with struvite is rarely evaluated. Removal of heavy metals and total organic carbon (TOC) in a greenhouse wastewater (GW) by struvite was investigated in this work. Presynthesized struvite was added to GW and removal of Zn (689 μg/L), Cu (151 μg/L), and TOC (51 mg/L) monitored from 1 to 26 d. Metal uptake in sodium nitrate solutions was used to assess competition, and the influence of other GW constituents on sorption. Struvite was also directly precipitated from GW (PPT). Recovered GW solids had 64–247 mg/kg Zn, 12–54 mg/kg Cu, and 1721–8806 mg/kg TOC, with lowest loadings for PPT and highest for 26 d solids. X-ray absorption spectroscopy detected polymerized Zn-phosphate, induced by dissolved phosphorus in GW, and Cu copolymerization, initially limited by aqueous Cu-organic complexation. Sorbed Cu shifts Fourier transform infrared-sensitive phosphate bands and changes the intensities of reflections in X-ray diffraction patterns of struvite more so than Zn. Struvite from GW is more susceptible to thermal decomposition than unreacted struvite, evolving CO(g), CO 2 (g), NH 3 (g), and H 2 O(g). Therefore, struvite from GW sorbs metals and organics, and can release sorbed and structural components to the aqueous and gas phases.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

AmeriFlux US-ABc Archbold grazed improved pasture

This is the AmeriFlux version of the carbon flux data for the site US-ABc Archbold grazed improved pasture. Site Description - This site is an improved pasture, regularly fertilized (nitrogen, ~26 kg/ha every 2 years) and limed (~229 kg/ha every 5 years, and historically received phosphorus fertilizer until 1986; . The soil type is a fine sandy Spodosol

Bernacchi, Carl [Global Change and Photosynthesis ↗

AmeriFlux US-ABd Archbold ungrazed improved pasture

This is the AmeriFlux version of the carbon flux data for the site US-ABd Archbold ungrazed improved pasture. Site Description - This site is an improved pasture, regularly fertilized (nitrogen, ~26 kg/ha every 2 years) and limed (~229 kg/ha every 5 years; and historically received phosphorus fertilizer until 1986; . The soil type is a fine sandy Spodosol . Grazing was removed in 2013-2015 for the duration of the study

Bernacchi, Carl [Global Change and Photosynthesis ↗

AmeriFlux FLUXNET-1F US-ABc Archbold grazed improved pasture

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-ABc Archbold grazed improved pasture. This is the FLUXNET version of the carbon flux data for the site US-ABc Archbold grazed improved pasture produced by applying the standard ONEFlux (1F) software. Site Description - This site is an improved pasture, regularly fertilized (nitrogen, ~26 kg/ha every 2 years) and limed (~229 kg/ha every 5 years, and historically received phosphorus fertilizer until 1986; . The soil type is a fine sandy Spodosol

Bernacchi, Carl [Global Change and Photosynthesis ↗

AmeriFlux FLUXNET-1F US-ABd Archbold ungrazed improved pasture

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-ABd Archbold ungrazed improved pasture. This is the FLUXNET version of the carbon flux data for the site US-ABd Archbold ungrazed improved pasture produced by applying the standard ONEFlux (1F) software. Site Description - This site is an improved pasture, regularly fertilized (nitrogen, ~26 kg/ha every 2 years) and limed (~229 kg/ha every 5 years; and historically received phosphorus fertilizer until 1986; . The soil type is a fine sandy Spodosol . Grazing was removed in 2013-2015 for the duration of the study

Bernacchi, Carl [Global Change and Photosynthesis ↗

An Eco-Friendly System for the Production of Value-Added Materials from Dairy Manure

A technoeconomic model has been developed to explore the viability of a two-stage anaerobic digester (AD) coupled with additional processes to increase the economic attractiveness of a new manure treatment system. The addition of a polyhydroxyalkanoate (PHA) reactor, algae cultivation system (ACS), and a biomass treatment system, such as, fast-pyrolysis or hydrothermal liquefaction (HTL) would further sequester carbon and nutrients, as well as add valuable products that can be sold or used on-site to mitigate costs. The Decision-support for Digester-Algae IntegRation for Improved Environmental and Economic Sustainability (DAIRIEES) model is used to evaluate the effectiveness and viability of this system to achieve economic and environmental sustainability by the dairy industry. The DAIRIEES model was used to evaluate the effectiveness and viability of this system to achieve economic viability and environmental sustainability by the dairy industry. A base case with mass flows and economics for a 10,000 herd dairy is considered. The integrated manure treatment system can reduce the amount of nitrogen released from the manure by 61.7%. If the ACS is not incorporated into the system, the nitrogen reduction drops to 19%. Similarly, the amount of phosphorus available for release to the environment is reduced by 37.4% with the full system, and by 26% for the system without the ACS. The results of the economic analysis indicate a net loss for the integrated system with algae cultivation. Without algae cultivation, the manure treatment system is profitable with a payback period of less than five years.

09 BIOMASS FUELS↗

Phosphate amendment drives bloom of RNA viruses after soil wet-up

Soil rewetting after a dry period results in a surge of activity and succession in both microbial and DNA virus communities. Less is known about the response of RNA viruses to soil rewetting—while they are highly diverse and widely distributed in soil, they remain understudied. We hypothesized that RNA viruses would show temporal succession following rewetting and that phosphate amendment would influence their trajectory, as viral proliferation may cause phosphorus limitation. Using 39 time-resolved metatranscriptomes and amplicon data, 2190 RNA viral populations were identified across five phyla, with 26 % of these predicted to infect bacteria, and 11 % fungi. Only 1.2 % of viral populations had annotated capsid genes, suggesting most persist via intracellular replication without a free virion phase. Phosphate amendment altered RNA viral community composition within the first week and amended vs. unamended communities remained distinguishable for up to three weeks. While the overall host community remained stable, certain bacterial populations showed reduced abundance in phosphate-amended soils, likely due to increased viral lysis, as RNA bacteriophages proliferated significantly. Notably, 60 % of the viruses with increased abundance under phosphate amendment belonged to basal Lenarviricota clades rather than well-known groups like Leviviricetes. We estimate RNA bacteriophage infections may affect 10 7 –10 9 bacteria per gram of soil, aligning with the total bacterial population (10 7 –10 10 g -1 soil), suggesting that RNA phages significantly influence bacterial communities post-wet-up, with phosphorus availability modulating this effect.

59 BASIC BIOLOGICAL SCIENCES↗

Novel Poly-Si:Ga/SiOx Passivating Contacts through Non-Equilibrium Doping

Poly-Si/SiOx passivating contacts are one of the key enablers for high-efficiency, low-cost c-Si solar cells. In recent years, record devices have reached efficiencies of 26% in the laboratory and 25% in the industry. The current cell structure utilizing a tunneling oxide passivating contact structure with a back phosphorus-doped poly- Si/SiOx passivating contact and a front boron diffused emitter suffers from large emitter recombination. Thus, replacing the front B diffused emitter with a p-type passivating contact is a route to overcome this deficiency. This gives rise to front/back poly-Si based passivating contacts. To address the low passivation performance of the B-doped poly-Si passivating contacts, we replace B with Ga as a novel p-type dopant to avoid dopant accumulation in the tunneling oxide, which is known to lead to large degradation loss in passivation quality. Here, we introduce a non-equilibrium method via pulsed laser melting to thermally melt and recrystallize the poly-Si and redistribute the dopants, achieving doping concentrations above the solid solubility limit (~4E19 cm-3). We demonstrate a good passivation quality with an iVoc of 721 mV with an active Ga doping concentration in poly-Si >1020 cm-3. Furthermore, we show a low contact resistivity of 33.2 +/- 9.3 mO cm2 using a diode model calculation. Finally, cross-section scanning spreading resistance microscopy was performed to determine the resistance profile across the non-homogeneously doped poly-Si layer.

c-Si↗

Phosphorus feedbacks constraining tropical ecosystem responses to changes in atmospheric CO 2 and climate

The effects of phosphorus (P) availability on carbon (C) cycling in the Amazon region are investigated using CLM-CNP. Within this paper, we demonstrate that the coupling of P dynamics reduces the simulated historical terrestrial C sink due to increasing atmospheric CO 2 concentrations ([CO 2 ]) by about 26%. Our exploratory simulations show that the response of tropical forest C cycling to increasing [CO 2 ] depends on how elevated CO 2 affects phosphatase enzyme production. The effects of warming are more complex, depending on the interactions between humidity, C, and nutrient dynamics. While a simulation with low humidity generally shows the reduction of net primary productivity (NPP), a second simulation with higher humidity suggests overall increases in NPP due to the dominant effects of reduced water stress and more nutrient availability. Lastly, our simulations point to the need for (1) new observations on how elevated [CO 2 ] affects phosphatase enzyme production and (2) more tropical leaf-scale measurements under different temperature/humidity conditions with different soil P availability.

54 ENVIRONMENTAL SCIENCES↗

Further Investigations of the Passive Optical Sample Assembly (POSA) - I Flight Experiment

The Passive Optical Sample Assembly-I (POSA-I), part of the Mir Environmental Effects Payload (MEEP), was designed to study the combined effects of contamination, atomic oxygen, ultraviolet radiation, vacuum, then-nal cycling, and other constituents of the space environment on spacecraft materials. The MEEP program is a Phase I International Space Station Risk Mitigation Experiment. Candidate materials for the International Space Station (ISS) were exposed in a specially designed "suitcase" carrier, with identical specimens facing either Mir or space. The payload was attached by EVA to the exterior of the Mir docking module during the STS-76 mission (f'ig. 1). It was removed during the STS-86 mission after an 18-month exposure. During the mission, it received approximately 7 x 1019 atoMS/CM2 atomic oxygen, as calculated by polymer mass loss, and 413 ESH of solar ultraviolet radiation on the Mir-facing side. The side facing away from Mir received significant contaminant deposition, so atomic oxygen fluence has not been reliably determined. The side facing away from Mir received 571 ESH of solar UV. Contamination was observed on both the Mir-facing and space-facing sides of the POSA-I experiment , with a greater amount of deposition on the space facing side than the Mir side. The contamination has been determined to be outgassed silicone photofixed by ultraviolet radiation and converted to silicate by atomic oxygen interaction. Electron spectroscopy for chemical analysis (ESCA) with depth profiling indicated the presence of 26 - 31 nm silicate on the Mir-facing side and 500 - 1000 nm silicate on the space-facing side. The depth profiling also showed that the contaminant layer was uniform, with a small amount of carbon present on the surface and trace amounts of nitrogen, phosphorus, sulfur, and tin. The surface carbon layer is likely due to post-flight exposure in the laboratory and is similar to carbonaceous deposits on control samples. EDAX and FTIR analysis concurred with ESCA for the presence of silicon, oxygen, and carbon. Nearly 400 samples were exposed on POSA-I, which included materials such as thermal control coatings polymeric films, optical materials, and multi-layer insulation blankets. A previous paper discussed the effects of the space environment exposure and contaminant deposition on candidate materials for ISS, including Z93P inorganic thermal control coating, various anodizes, and multi-layer insulation blankets. This paper details the investigation of environmental effects on the remainder of POSA-I samples, particularly the innovative conductive thermal control coatings developed by AZ Technology of Huntsville, AL and HT Research Institute of Chicago, IL. The silicone/silicate contamination had a significant impact on the solar absorptance of white inorganic thermal control coatings on the space-facing side of POSA-I. The effect of contamination on electrical conductivity is discussed. Samples of conductive anodized aluminum developed by Boundary Technologies of Buffalo Grove, IL were also exposed on POSA-I. The effects of the space environment and contaminant deposition on the optical and electrical properties of the conductive anodized aluminum are discussed.

Finckenor, Miria M.↗