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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Quantification of glioblastoma progression in zebrafish xenografts: Adhesion to laminin alpha 5 promotes glioblastoma microtumor formation and inhibits cell invasion

Highlights: • Developed an embryo-larval zebrafish model to study GBM progression. • Quantitatively measured GBM BV association, invasion and microtumor formation. • Laminin alpha 5 decreases U251MG dispersal and increases microtumors. • Microenvironmental laminin alpha 5 slows U251MG cell invasion in vivo. Glioblastoma (GBM) is a deadly disease due to its ability to quickly invade and destroy brain tissue. Slowing or stopping GBM cell progression is crucial to help those inflicted with the disease. Our lab created an embryo-larval zebrafish xenograft model as a tool to study human GBM progression in an observable brain environment. The zebrafish brain is a dynamic and complex environment providing an optimal setting for studying GBM cell progression. Here we demonstrate the ability of our model to quantitate GBM proliferation, dispersal, blood vessel association, microtumor formation, and individual cell invasion by evaluating the importance of an extracellular matrix protein, laminin alpha 5 (lama5), on U251MG cell progression. Lama5 has been implicated in cancer cell survival, proliferation and invasion and is a known adhesion site for GBM cells. While lama5 is highly expressed in endothelial cells in the brain, it is unknown how lama5 affects GBM behavior. Using a lama5 morpholino, we discovered that lama5 decreased U251MG dispersal by 23% and doubles the formation of blood vessel dependent microtumors. Despite lama5 being a known attachment site for GBM, lama5 expression had no effect on U251MG association with blood vessels. Analysis of individual U251MG cells revealed lama5 significantly lowered invasion as mobile U251MG cells traveled 32.5 μm less, invaded 5.0 μm/hr slower and initiated invasion 60% few times per cell.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

Human α-defensin 5 suppressed colon cancer growth by targeting PI3K pathway

Defensins are highly conserved antimicrobial peptides, which ubiquitously expressed in different species. In addition to the functions in host defense, their aberrant expression have also been documented in cancerous tissue including breast cancer, lung caner and renal carcinoma etc. Whereas, roles of Defensin Alpha 5 (DEFA5) in colon cancer has not been explored. Bioinformatic analysis was used to study the expression of DEFA5 and its correlation with clinical outcomes; Western blot, qPCR, Co-immunoprecipitation, xenograft models were used to the study the molecular mechanism. Decreased expression of DEFA5 at protein level was observed in colon tissues. Colon cancer cell lines proliferation and colony formation capacity were significantly suppressed by DEFA5 overexpression. Moreover, in vivo tumor growth in nude mice was also suppressed by DEFA5 overexpression, suggesting a tumor suppressor role of DEFA5 in colon cancer. Mechanistically, DEFA5 directly binds to the subunits of PI3K complex, thus attenuates the downstream signaling transduction, leads to delayed cell growth and metastasis. Collectively, we concluded that DEFA5 showed an inhibitory effect in colon cancer cell growth and may serve as a potential tumor suppressor in colon cancer.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

The $^3$He+$^5$He$\rightarrow $ $\alpha $+$\alpha $ reaction below the Coulomb barrier via the Trojan Horse Method

For the first time in an application to nuclear astrophysics, a process induced by the unstable 5 He = ( 4 He-n) nucleus, the 3 He+ 5 He→2α reaction, has been studied through the Trojan Horse Method (THM). For that purpose, the quasi-free (QF) contribution of the 9 Be( 3 He,αα) 4 He reaction was selected at E 3 He =4 MeV incident energy. The reaction was studied in a kinematically complete experiment following a recent publication, where for the quasi free contribution the momentum distribution between α and 5 He particle cluster in the 9 Be nucleus in the ground state have been extracted. The angular distribution of the QF 3 He+ 5 He→2α reaction was measured at θ cm = 78°–115°. The energy dependence of the differential cross section of the 3 He+ 5 He→2α virtual reaction was extracted in the energy range E cm = 0–650 keV. In conclusion, the total cross section obtained from the Trojan-horse method was normalized to absolute cross sections from a theoretical calculation in the energy range E cm =300–620 keV.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2020

Evaluation of radiation hardness of semiconductor materials against alpha particles for an API detector

An Associated Particle Imaging (API) system consists of a high vacuum chamber where deuterium ions are accelerated on a tritium-loaded target, resulting in alpha particles and neutrons emitted back-to-back, the latter escaping the chamber and used, for example, for tomography of a high-Z sample. An accurate determination of the alpha position is crucial to determine the trajectory of the neutron. Existing API systems have several limitations which a semiconductor-based API detector placed inside the vacuum chamber should not present. The semiconductor material can be either silicon or diamond. In particular, large and fast signals are generated by the alpha interactions in these materials. A pixelated API detector will measure the time and hit position of the alphas produced in the reaction. However, during the lifetime of the generator, the semiconductor detector will be exposed to an intense flux of alpha particles that will degrade its performance over time. To assess the radiation hardness of silicon and diamond against the alpha particles, we exposed single diodes made of either of the two materials to a 5 MeV alpha flux generated by an 241Am radioactive source. During irradiation, the diodes were biased and mounted on current-sensitive preamplifier boards. We have therefore been able to measure insitu the evolution of the waveforms as the damage was accumulating in their substrates.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2020

Materials Data on MnC5IO5 by Materials Project

IMn(CO)5 is alpha U structured and crystallizes in the orthorhombic Cmcm space group. The structure is zero-dimensional and consists of four IMn(CO)5 clusters. Mn3+ is bonded in a 6-coordinate geometry to five C+1.60+ and one I1- atom. There is one shorter (1.84 Å) and four longer (1.88 Å) Mn–C bond length. The Mn–I bond length is 2.76 Å. There are two inequivalent C+1.60+ sites. In the first C+1.60+ site, C+1.60+ is bonded in a distorted single-bond geometry to one Mn3+ and one O2- atom. The C–O bond length is 1.15 Å. In the second C+1.60+ site, C+1.60+ is bonded in a single-bond geometry to one Mn3+ and one O2- atom. The C–O bond length is 1.15 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. I1- is bonded in a single-bond geometry to one Mn3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cr(NO3)5 by Materials Project

Cr(NO3)5 is alpha Selenium structured and crystallizes in the trigonal P3_221 space group. The structure is zero-dimensional and consists of three Cr(NO3)5 clusters. Cr5+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of Cr–O bond distances ranging from 2.04–2.07 Å. There are three inequivalent N5+ sites. In the first N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.24 Å) and one longer (1.31 Å) N–O bond length. In the second N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of N–O bond distances ranging from 1.24–1.30 Å. In the third N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.21 Å) and two longer (1.31 Å) N–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the second O2- site, O2- is bonded in an L-shaped geometry to one Cr5+ and one N5+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Cr5+ and one N5+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the seventh O2- site, O2- is bonded in a bent 120 degrees geometry to one Cr5+ and one N5+ atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to one N5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ReC5IO5 by Materials Project

ReI(CO)5 is alpha carbon monoxide-derived structured and crystallizes in the orthorhombic Cmcm space group. The structure is zero-dimensional and consists of twenty formaldehyde molecules and four iodorhenium molecules.

36 MATERIALS SCIENCE↗
DOE OSTI2019

BUILDING 9201-5

Building 9201-5 (Alpha-5) functioned as a uranium enrichment facility during World War II and furthered the plant's mission of producing enriched uranium for the atomic bomb. As an Alpha processing facility associated with the Manhattan Project, Building 9201-5 aided in the development of wholly new technology and substantially advanced the field of nuclear science. In terms of facility planning, project engineers originally designed all Alpha and Beta buildings with "zero tolerance" for building movement or settling as the successful operation of the Y-12 Plant's calutrons depended on absolute structural stability. After World War II, the building was used in the plant’s COLEX process of the 1950s which separated the element Lithium-6 (Li-6). This was an important component in the manufacture of hydrogen bombs and the COLEX process is of notable significance in Cold War history. Building 9201-5 is eligible for inclusion in the National Register.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
DOE OSTI2020

Materials Data on Tc(CO)5 by Materials Project

Tc(CO)5 is Cubic alpha N2-like structured and crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of eight Tc(CO)5 clusters. Tc3- is bonded in a square pyramidal geometry to five C+2.60+ atoms. There are a spread of Tc–C bond distances ranging from 1.94–2.01 Å. There are five inequivalent C+2.60+ sites. In the first C+2.60+ site, C+2.60+ is bonded in a linear geometry to one Tc3- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.60+ site, C+2.60+ is bonded in a linear geometry to one Tc3- and one O2- atom. The C–O bond length is 1.16 Å. In the third C+2.60+ site, C+2.60+ is bonded in a linear geometry to one Tc3- and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+2.60+ site, C+2.60+ is bonded in a linear geometry to one Tc3- and one O2- atom. The C–O bond length is 1.16 Å. In the fifth C+2.60+ site, C+2.60+ is bonded in a linear geometry to one Tc3- and one O2- atom. The C–O bond length is 1.16 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.60+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.60+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.60+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+2.60+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one C+2.60+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Conceptual design of DIII-D experiments to diagnose the lifetime of spin polarized fuel

Abstract In magnetic fusion experiments, the cross sections for the D-T and D- 3 He fusion reactions are increased by as much as 50% if the fuel remains spin polarized parallel to the magnetic field. The goal of this study is to assess the feasibility of lifetime measurements of spin polarization, in magnetic fusion relevant conditions, on the DIII-D tokamak using relative changes in charged fusion product (CFP) loss measurements that depend upon the differential fusion cross section d σ /dΩ. Relative measurements that capture changes in the escaping CFP pitch, poloidal, and energy distributions are studied in two realistic TRANSP calculated plasma scenarios: (a) vector-polarized 3 He and D pellets are injected into a hot hydrogen plasma to produce thermonuclear reactions, and (b) a tensor-polarized deuterium pellet is injected into an L-mode hydrogen background plasma that includes unpolarized 3 He neutral beam injection. Ideal CFP signals in both scenarios show substantial pitch sensitivity to polarization for 14.7 MeV proton detection at a poloidal angle of − 56 ∘ (on the outer wall in the ion ∇ B direction), and strong sensitivity to polarization for 3.6 MeV alpha flux detection by an array of poloidal detectors. Energy-resolved measurements of 14.7 MeV protons are also sensitive to the degree of polarization for the − 56 ∘ port in the beam-plasma scenario. A realistic assessment of CFP signals in the thermonuclear scenario show count rates in the range of 2 × 10 4 cps for pitch-resolved proton detection and 2 × 10 5 cps for alpha flux measurements. Reduced chi-squared χ r 2 calculations show polarization lifetime measurements are feasible for either proton or alpha detection of both enhanced or suppressed polarization for the thermonuclear scenario. Measurements of gamma rays produced in the weak D + 3 He → γ + 5 Li branch complement the CFP measurements.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2020

Materials Data on Na26(Ge3Au8)5 by Materials Project

Na26(Au8Ge3)5 is alpha-derived structured and crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. there are eleven inequivalent Na sites. In the first Na site, Na is bonded in a 12-coordinate geometry to three Na, nine Au, and three Ge atoms. There are a spread of Na–Na bond distances ranging from 3.06–3.56 Å. There are a spread of Na–Au bond distances ranging from 3.10–3.36 Å. There are a spread of Na–Ge bond distances ranging from 3.27–3.35 Å. In the second Na site, Na is bonded in a 12-coordinate geometry to two Na, nine Au, and three Ge atoms. The Na–Na bond length is 3.46 Å. There are a spread of Na–Au bond distances ranging from 3.09–3.38 Å. There are a spread of Na–Ge bond distances ranging from 3.27–3.38 Å. In the third Na site, Na is bonded in a 10-coordinate geometry to two equivalent Na, ten Au, and three Ge atoms. Both Na–Na bond lengths are 3.06 Å. There are a spread of Na–Au bond distances ranging from 3.10–3.21 Å. There are a spread of Na–Ge bond distances ranging from 3.19–3.27 Å. In the fourth Na site, Na is bonded in a 4-coordinate geometry to nine Au and four Ge atoms. There are a spread of Na–Au bond distances ranging from 3.08–3.27 Å. There are two shorter (3.11 Å) and two longer (3.27 Å) Na–Ge bond lengths. In the fifth Na site, Na is bonded in a 11-coordinate geometry to two equivalent Na, eight Au, and five Ge atoms. Both Na–Na bond lengths are 3.16 Å. There are four shorter (3.10 Å) and four longer (3.17 Å) Na–Au bond lengths. There are a spread of Na–Ge bond distances ranging from 3.10–3.18 Å. In the sixth Na site, Na is bonded in a 11-coordinate geometry to two Na, ten Au, and three Ge atoms. Both Na–Na bond lengths are 3.00 Å. There are a spread of Na–Au bond distances ranging from 3.10–3.33 Å. There are one shorter (3.18 Å) and two longer (3.41 Å) Na–Ge bond lengths. In the seventh Na site, Na is bonded in a 5-coordinate geometry to four Na, nine Au, and three Ge atoms. The Na–Na bond length is 3.31 Å. There are a spread of Na–Au bond distances ranging from 3.13–3.53 Å. There are one shorter (3.26 Å) and two longer (3.35 Å) Na–Ge bond lengths. In the eighth Na site, Na is bonded in a 5-coordinate geometry to one Na, nine Au, and two equivalent Ge atoms. There are a spread of Na–Au bond distances ranging from 3.13–3.50 Å. Both Na–Ge bond lengths are 3.41 Å. In the ninth Na site, Na is bonded in a 5-coordinate geometry to four Na, eight Au, and four Ge atoms. The Na–Na bond length is 3.49 Å. There are a spread of Na–Au bond distances ranging from 3.10–3.49 Å. There are a spread of Na–Ge bond distances ranging from 3.25–3.58 Å. In the tenth Na site, Na is bonded in a 5-coordinate geometry to one Na, seven Au, and three Ge atoms. There are a spread of Na–Au bond distances ranging from 3.08–3.28 Å. There are one shorter (3.27 Å) and two longer (3.37 Å) Na–Ge bond lengths. In the eleventh Na site, Na is bonded in a 7-coordinate geometry to seven Au and three Ge atoms. There are a spread of Na–Au bond distances ranging from 3.09–3.25 Å. There are one shorter (3.36 Å) and two longer (3.37 Å) Na–Ge bond lengths. There are fourteen inequivalent Au sites. In the first Au site, Au is bonded in a 12-coordinate geometry to five Na, one Au, and one Ge atom. The Au–Au bond length is 2.87 Å. The Au–Ge bond length is 2.55 Å. In the second Au site, Au is bonded in a 12-coordinate geometry to five Na, one Au, and one Ge atom. The Au–Au bond length is 2.88 Å. The Au–Ge bond length is 2.56 Å. In the third Au site, Au is bonded in a 1-coordinate geometry to five Na, one Au, and one Ge atom. The Au–Au bond length is 2.88 Å. The Au–Ge bond length is 2.53 Å. In the fourth Au site, Au is bonded in a 12-coordinate geometry to five Na, one Au, and one Ge atom. The Au–Au bond length is 2.90 Å. The Au–Ge bond length is 2.55 Å. In the fifth Au site, Au is bonded in a 1-coordinate geometry to five Na, one Au, and one Ge atom. The Au–Au bond length is 2.92 Å. The Au–Ge bond length is 2.55 Å. In the sixth Au site, Au is bonded to twelve Au atoms to form AuAu12 cuboctahedra that share corners with two equivalent GeNa6Au6 cuboctahedra. In the seventh Au site, Au is bonded in a 12-coordinate geometry to six Na, three Au, and three Ge atoms. There are one shorter (2.82 Å) and two longer (2.89 Å) Au–Au bond lengths. There are a spread of Au–Ge bond distances ranging from 2.61–2.96 Å. In the eighth Au site, Au is bonded in a 12-coordinate geometry to six Na, four Au, and two Ge atoms. There are a spread of Au–Au bond distances ranging from 2.82–3.09 Å. There are one shorter (2.59 Å) and one longer (2.82 Å) Au–Ge bond lengths. In the ninth Au site, Au is bonded in a 12-coordinate geometry to six Na, three Au, and three Ge atoms. There are one shorter (2.90 Å) and one longer (2.91 Å) Au–Au bond lengths. There are a spread of Au–Ge bond distances ranging from 2.59–2.90 Å. In the tenth Au site, Au is bonded in a 12-coordinate geometry to six Na, three Au, and three Ge atoms. There are one shorter (2.91 Å) and one longer (2.95 Å) Au–Au bond lengths. There are a spread of Au–Ge bond distances ranging from 2.60–2.88 Å. In the eleventh Au site, Au is bonded in a 12-coordinate geometry to six Na, four Au, and two Ge atoms. There are one shorter (2.90 Å) and one longer (3.02 Å) Au–Au bond lengths. There are one shorter (2.55 Å) and one longer (2.68 Å) Au–Ge bond lengths. In the twelfth Au site, Au is bonded in a 12-coordinate geometry to six Na, four Au, and two Ge atoms. The Au–Au bond length is 3.08 Å. There are one shorter (2.56 Å) and one longer (2.64 Å) Au–Ge bond lengths. In the thirteenth Au site, Au is bonded in a 3-coordinate geometry to seven Na, five Au, and two Ge atoms. The Au–Au bond length is 2.75 Å. There are one shorter (3.16 Å) and one longer (3.21 Å) Au–Ge bond lengths. In the fourteenth Au site, Au is bonded in a 1-coordinate geometry to seven Na, four equivalent Au, and one Ge atom. The Au–Ge bond length is 2.49 Å. There are seven inequivalent Ge sites. In the first Ge site, Ge is bonded in a 11-coordinate geometry to six Na and five Au atoms. In the second Ge site, Ge is bonded in a 12-coordinate geometry to five Na and five Au atoms. In the third Ge site, Ge is bonded in a 11-coordinate geometry to six Na and five Au atoms. In the fourth Ge site, Ge is bonded in a 12-coordinate geometry to six Na and six Au atoms. In the fifth Ge site, Ge is bonded to six Na and six Au atoms to form distorted GeNa6Au6 cuboctahedra that share a cornercorner with one AuAu12 cuboctahedra and an edgeedge with one GeNa6Au6 cuboctahedra. In the sixth Ge site, Ge is bonded in a 1-coordinate geometry to seven Na and five Au atoms. In the seventh Ge site, Ge is bonded in a 12-coordinate geometry to three Na, four Au, and one Ge atom. The Ge–Ge bond length is 2.70 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Materials Data on Ti4(FeSb)5 by Materials Project

Ti4(FeSb)5 is alpha-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are four inequivalent Ti sites. In the first Ti site, Ti is bonded to three equivalent Fe and three equivalent Sb atoms to form distorted TiFe3Sb3 octahedra that share corners with six equivalent FeSb6 octahedra, edges with six equivalent TiFe3Sb3 octahedra, and a faceface with one FeSb6 octahedra. The corner-sharing octahedral tilt angles are 41°. All Ti–Fe bond lengths are 2.49 Å. All Ti–Sb bond lengths are 2.91 Å. In the second Ti site, Ti is bonded in a 6-coordinate geometry to three equivalent Fe and three equivalent Sb atoms. All Ti–Fe bond lengths are 2.49 Å. All Ti–Sb bond lengths are 2.92 Å. In the third Ti site, Ti is bonded in a 6-coordinate geometry to three equivalent Fe and three equivalent Sb atoms. All Ti–Fe bond lengths are 2.51 Å. All Ti–Sb bond lengths are 2.92 Å. In the fourth Ti site, Ti is bonded to three equivalent Fe and three equivalent Sb atoms to form distorted edge-sharing TiFe3Sb3 octahedra. All Ti–Fe bond lengths are 2.49 Å. All Ti–Sb bond lengths are 2.89 Å. There are five inequivalent Fe sites. In the first Fe site, Fe is bonded to six Sb atoms to form distorted FeSb6 octahedra that share corners with six equivalent TiFe3Sb3 octahedra, edges with six equivalent FeSb6 octahedra, and a faceface with one TiFe3Sb3 octahedra. The corner-sharing octahedral tilt angles are 41°. There are three shorter (2.60 Å) and three longer (2.67 Å) Fe–Sb bond lengths. In the second Fe site, Fe is bonded in a 6-coordinate geometry to three equivalent Ti and three equivalent Sb atoms. All Fe–Sb bond lengths are 2.61 Å. In the third Fe site, Fe is bonded to three equivalent Ti and three equivalent Sb atoms to form distorted edge-sharing FeTi3Sb3 pentagonal pyramids. All Fe–Sb bond lengths are 2.60 Å. In the fourth Fe site, Fe is bonded in a 6-coordinate geometry to three equivalent Ti and three equivalent Sb atoms. All Fe–Sb bond lengths are 2.61 Å. In the fifth Fe site, Fe is bonded in a 6-coordinate geometry to three equivalent Ti and three equivalent Sb atoms. All Fe–Sb bond lengths are 2.68 Å. There are five inequivalent Sb sites. In the first Sb site, Sb is bonded in a 6-coordinate geometry to six Fe atoms. In the second Sb site, Sb is bonded in a 6-coordinate geometry to three equivalent Ti and three equivalent Fe atoms. In the third Sb site, Sb is bonded in a 6-coordinate geometry to three equivalent Ti and three equivalent Fe atoms. In the fourth Sb site, Sb is bonded in a 6-coordinate geometry to three equivalent Ti and three equivalent Fe atoms. In the fifth Sb site, Sb is bonded in a 6-coordinate geometry to three equivalent Ti and three equivalent Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Systematic evaluation of fast neutron sensing with Cesium Hafnium Chloride

Cesium Hafnium Chloride (CHC) is a promising new scintillator for dual mode sensing of both neutrons and gamma-rays. The high chlorine content allows for both 35 Cl(n,p) 35 S and 35 Cl(n,α) 32 P reaction channels leading to reliable detection of fast neutrons. By utilizing pulse shape discrimination (PSD), these neutron interactions may be reliably separated from gamma-ray signals with a high figure-of-merit (FOM) after optimization of the PSD algorithm. Here, in this study, the PSD algorithm settings for CHC were systematically investigated using a bare 252 Cf and a lead shielded plutonium beryllium neutron source. It was found that the PSD algorithm settings affects both the FOM and the neutron detection efficiency, but a FOM as high as 4.5 for alpha particles was observed in one data processing scenario. Further, an intrinsic 5 parts per million alpha emitting contamination was observed in the sample, which we attribute to natural uranium.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2021

Atomic forces from Dirac-Kohn-Sham equations: Implementation in flexible (APW+lo/LAPW)+LO basis set

The atomic forces formulation based on the Dirac-Kohn-Sham equation and the flexible (APW+lo/LAPW)+LO basis set is presented here. The formulation was implemented in the code FlapwMBPT and allows a user to easily switch between different basis functions of the augmentation type (APW or LAPW) and between different kind of local orbitals. Similar to the work (Phys.Rev.B 91 (2015) 035105), the implementation takes into account small discontinuities of the wave functions, density, and potential at the muffin-tin sphere boundaries. Applications to the materials with strong relativistic effects, such as $\alpha$-Uranium, PuCoGa$_{5}$, and FePt, demonstrate robustness of the method. The comparison of the calculated forces with the ones obtained by numerical differentiation of free energy shows close agreement with deviations about 0.1% or less.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2026

Coordination of Anle138b to Silver Results in Selective Reduction of a C-terminal truncated Alpha-synuclein Protein and Increased Aggregate Size

Parkinson’s disease (PD) is a prevalent age-related neurodegenerative syndrome, partially thought to be caused by a decrease in alpha-synuclein proteostasis. Anle138b = 5-(1,3-benzodioxol-5-yl)-3-(3-bromophenyl)-1H-pyrazole (HL), is undergoing clinical trials as a promising mitigator of alpha-synuclein aggregation. Because complexation to metals is known to modulate the activity of several drugs, we have prepared and characterized: H2L(ClO4), [CuI(µ-L)]3, and [AgI(µ-L)]3. To better understand the bioviability of these compounds, we monitored their effects in a cell culture model of alpha-synuclein protein aggregation using human alpha-synuclein pre-formed fibrils (PFFs). Using two different anti-alpha-synuclein antibodies, our data suggests that [AgI(µ-L)]3 decreases a C-terminal truncated protein that is approximately 12.4 kDa, as well as increases the size and alters the shape of PFF-induced aggregates. This indicates that [AgI(µ-L)]3 impacts aggregation in a manner different from HL and may serve as a novel tool for studying C-terminal truncation related aggregation chemistry.

Rue, Kelly L.↗
DOE OSTI2022

Light output quenching in response to deuterium-ions and alpha particles and pulse shape discrimination in deuterated trans-stilbene

We characterized the light output response of a new 140 cm 3 stilbene-d 12 crystal up to 14.1 MeV neutron energies using a coincidence neutron scattering system. We also characterized its light output response to alpha particles in the 5 to 6 MeV energy range. The excellent PSD capability of the stilbene-d 12 detector allowed us to select light pulses produced by particles of increasing ionization density, namely electrons, protons, deuterium-ions, and alpha particles. The measured fast decay component of the light pulses is increasingly quenched as the ionization density of the particle in the crystal increases. Consistently with this finding, the Birks’ quenching parameter of alpha particles is approximately 8.5 times larger compared to the quenching of deuterium ions, produced by neutron scattering interactions. The reported experimental characterization will allow high-fidelity modeling of the detector enabling its application for fast-neutron detection and spectroscopy in nuclear physics, radiation protection, nuclear security, and non-proliferation.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Treatment of cholinergic‐induced status epilepticus with polytherapy targeting GABA and glutamate receptors

Abstract Despite new antiseizure medications, the development of cholinergic‐induced refractory status epilepticus (RSE) continues to be a therapeutic challenge as pharmacoresistance to benzodiazepines and other antiseizure medications quickly develops. Studies conducted by Epilepsia . 2005;46:142 demonstrated that the initiation and maintenance of cholinergic‐induced RSE are associated with trafficking and inactivation of gamma‐aminobutyric acid A receptors (GABA A R) thought to contribute to the development of benzodiazepine pharmacoresistance. In addition, Dr. Wasterlain's laboratory reported that increased N‐methyl‐ d ‐aspartate receptors (NMDAR) and alpha‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid receptors (AMPAR) contribute to enhanced glutamatergic excitation ( Neurobiol Dis . 2013;54:225; Epilepsia . 2013;54:78). Thus, Dr. Wasterlain postulated that targeting both maladaptive responses of reduced inhibition and increased excitation that is associated with cholinergic‐induced RSE should improve therapeutic outcome. We currently review studies in several animal models of cholinergic‐induced RSE that demonstrate that benzodiazepine monotherapy has reduced efficacy when treatment is delayed and that polytherapy with drugs that include a benzodiazepine (eg midazolam and diazepam) to counter loss of inhibition, concurrent with an NMDA antagonist (eg ketamine) to reduce excitation provide improved efficacy. Improved efficacy with polytherapy against cholinergic‐induced seizure is demonstrated by reduction in (1) seizure severity, (2) epileptogenesis, and (3) neurodegeneration compared with monotherapy. Animal models reviewed include pilocarpine‐induced seizure in rats, organophosphorus nerve agent (OPNA)‐induced seizure in rats, and OPNA‐induced seizure in two mouse models: (1) carboxylesterase knockout (Es1 −/− ) mice which, similarly to humans, lack plasma carboxylesterase and (2) human acetylcholinesterase knock‐in carboxylesterase knockout (KIKO) mice. We also review studies showing that supplementing midazolam and ketamine with a third antiseizure medication (valproate or phenobarbital) that targets a nonbenzodiazepine site rapidly terminates RSE and provides further protection against cholinergic‐induced SE. Finally, we review studies on the benefits of simultaneous compared with sequential drug treatments and the clinical implications that lead us to predict improved efficacy of early combination drug therapies. The data generated from seminal rodent studies of efficacious treatment of cholinergic‐induced RSE conducted under Dr. Wasterlain's guidance suggest that future clinical trials should treat the inadequate inhibition and temper the excess excitation that characterize RSE and that early combination therapies may provide improved outcome over benzodiazepine monotherapy.

59 BASIC BIOLOGICAL SCIENCES↗