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The Gaerttner LINAC Center at RPI uses a 60 MeV electron linear accelerator to produce short pulses of neutrons with duration of 5-5000 ns. The main research thrust at the Center is nuclear data for nuclear reactors and criticality safety applications. The Center includes several setups for time-of-flight measurements including neutron transmission, capture and scattering detectors, and a lead slowing-down spectrometer. Experiments were designed to produce neutron interaction cross sections that cover the energy range of 0.01 eV to 20 MeV. Recently added experiments include: setups for keV and fast neutron transmission, a C6D6 detector array for keV neutron capture measurements, and a fast neutron scattering system. Results discussed here include fast neutron scattering and angular distributions for natFe, iron capture measurements for incident neutrons from 1 keV to 2 MeV, fast neutron transmission through W and H2O samples, and keV transmission through Mo isotopes.

The nuclear data program at the Rensselaer Polytechnic Institute (RPI) is centered around a 60 MeV pulsed electron Linear Accelerator (LINAC) configured to deliver pulsed neutron beams. The LINAC electron pulse width can vary between 5 ns and 5 us, a repetition rate of 1–500 pulses per second and neutron yield of up to 1013 n/s. Over the years several experimental setups and techniques were developed to enable a variety of measurement capabilities. The experiments cover the energy range from 0.001 eV to 20 MeV and included neutron transmission, capture, scattering and fission measurements. The facility is also equipped with a Lead Slowing-Down Spectrometer (LSDS) producing a high neutron flux that is used for simultaneous measurements of the fission cross section and fission fragment mass and energy distributions. Detectors for (n, alpha) and (n, p) cross section measurements using the LSDS were also developed and measurements of (n, alpha) cross section were completed. The high neutron flux inside the LSDS enables measurements on small samples (sub micrograms) or samples with small cross section (sub millibarns). In order to fully utilize the capabilities of the facility, several measurement techniques were developed; high accuracy (

Several indicators have been identified for the conservation and maintenance of soil criterion in the Montreal Protocol. The objective of this study was to use soil compaction and disturbance measures to determine harvesting impacts at a landscape scale in the boreal forest of Saskatchewan. Forest harvesting impacts were studied pre and postharvest for five harvested sites by (i) sampling soil bulk density ([D.sub.b]) at prescribed grid-points, and (ii) measuring soil disturbance regimes on two 30-m transects at each grid-point. Mean soil [D.sub.b] in the harvested area increased significantly (8-11%) from pre to postharvest conditions for the two winter-harvested sites at both the 10- and 20-cm depths, while two of the three summer harvested sites also showed significant [D.sub.b] increases (7-15%) at the 10-cm depth. Combining all five sites, showed that after harvest 32% of all the grid-points had an increased [D.sub.b] of >15%. Mean soil [D.sub.b] at a 10-cm depth for roadways and landings was significantly higher (8-14%) than postharvest [D.sub.b] for postharvest levels at four of the five harvested sites. Surface soil disturbance regimes were higher for the summer-harvested sites than that for the winter-harvested sites. Landscape position showed no significant differences in [D.sub.b] between the shoulder, backslope, and footslope positions; however, within each landscape position, significant differences in [D.sub.b] were found between pre and postharvest conditions. Soil [D.sub.b] and soil disturbance regimes measured on a grid basis provided a simple, but reliable method for monitoring soil compaction and disturbance effects from harvesting at a landscape scale.

Neutron scattering from a copper sample was measured at Rensselaer Polytechnic Institute utilizing the quasi-differential method. The measurement spanned the energy range from 0.5 to 20 MeV using the high-energy scattering system and from 2 keV to 0.5 MeV using the new mid-energy scattering system. Copper was selected as a material of interest to measure due to large discrepancies between experiments and simulations of the Zeus benchmark. The Zeus benchmark consists of a copper reflected highly enriched uranium system, and the angular distribution of copper scattering was thought to potentially be the cause of the discrepancy. The copper measurements found differences in the scattering response particularly in the incident energy region from 1 to 2 MeV for the high-energy measurement and from 2 to 4 keV in the mid-energy system. These differences are particularly noticeable at angles near 90 deg in the high-energy system and back angles in the mid-energy system. Additionally, for ENDF/B-VIII.0 there is a large discrepancy at the forward angle in the energy range around 0.5 MeV. For these reasons, a new evaluation of copper scattering utilizing these results is recommended and perhaps could help to improve the agreement with the Zeus benchmarks. [ABSTRACT FROM AUTHOR]

A corrected Zhang model calculates the distribution of radial energy deposition near the track of energetic charged particles in silicon. The tests were carried out in an energy range between 10 mega electron volts to 30 giga electron volts. The results agree well with values obtained from Monte Carlo simulations and stopping power tables.

The Pfizer-BioNTech coronavirus disease 2019 (COVID-19) vaccine is the first novel nucleoside-modified messenger ribonucleic acid (modRNA) vaccine to receive Emergency Use Authorization from the Food and Drug Administration in the United States. It is indicated to be used in patients ≥12 years-of-age as of May 25th, 2021, including populations with high atherosclerotic cardiovascular disease (ASCVD) burden. However, little is known about the potential impact this vaccine may have on serum lipoprotein levels in patients with familial hypercholesteremia (FH), who are predisposed to high ASCVD burden due to elevated low-density lipoprotein cholesterol (LDL-C). We present an interesting case where a patient with heterozygous FH (HeFH) and elevated triglycerides (TG)-controlled for years on medication and apheresis-experienced significantly elevated TG, one day after receiving his second Pfizer-BioNTech COVID-19 vaccine dose. It is not known whether this adverse event may be seen in other FH patients and may be worth assessing in such patients to determine the possibility of a rare adverse reaction from a COVID-19 vaccine. [ABSTRACT FROM AUTHOR]

Neutron capture and transmission measurements were carried out from thermal to 2000 eV on both solid and liquid samples containing elemental cesium (133Cs). This work describes the extension of the R-matrix analysis of these data from 600 to 2000 eV by correcting the capture data for false capture in the NaI detector. These false capture–corrected capture and transmission data were analyzed for resonance parameters utilizing the SAMMY Bayesian analysis code to simultaneously fit both the capture and transmission data. Parameters were obtained for 53 cesium resonances over the 600- to 2000-eV energy range. The s-wave strength function was determined over the energy range from 0 to 1800 eV for both spin J = 3 and J = 4 resonances. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Familial hypercholesterolemia (FH) is an autosomal codominant genetic disorder associated with defective hepatic uptake of circulating low-density lipoproteins (LDL), which can lead to premature atherosclerotic cardiovascular disease (ASCVD). Evidence suggests elevated lipoprotein(a) (Lp(a)) levels in FH patients may also increase their ASCVD risk. We present a case series of 2 FH patients where a daughter has a higher ASCVD burden than her mother due to the daughter having elevated Lp(a). This underscores the importance of including Lp(a) in cascade lipid screening in FH patients and their first-degree relatives. [ABSTRACT FROM AUTHOR]