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The $^{174}$Yb($^{29}$Si,5n) reaction at 148 MeV with thin targets was usedto populate high-angular momentum states in $^{198}$Po. Resulting $\gamma$ rayswere observed with Gammasphere. A weakly-populated superdeformed band of 10$\gamma$-ray transitions was found and has been assigned to $^{198}$Po. This isthe first observation of a SD band in the $A \approx 190$ region in a nucleuswith $Z > 83$. The ${\cal J}^{(2)}$ of the new band is very similar to those ofthe yrast SD bands in $^{194}$Hg and $^{196}$Pb. The intensity profile suggeststhat this band is populated through states close to where the SD band crossesthe yrast line and the angular momentum at which the fission process dominates.

We have studied via in-beam -ray spectroscopy Po196 and Po198, which are the first neutron-deficient Po isotopes to exhibit a collective low-lying structure. The ratios of yrast state energies and the E2 branching ratios of transitions from non-yrast to yrast states are indicative of a low-lying vibrational structure. The onset of collective motion in these isotopes can be attributed to the opening of the neutron i13/2 orbital at N112 and the resulting large overlap between the two valence protons in the h9/2 orbital and the valence neutrons in the i13/2 orbital. © 1995 The American Physical Society.

The National Ignition Facility (NIF) has 48 Real-Time Nuclear Activation Detectors distributed around the target chamber capable of measuring deuterium-triton reaction neutron yields with high precision. In this work, we extend this functionality to deuterium-deuterium (DD) reaction neutrons using a nuclear reaction that occurs in the detector's scintillator material. The corresponding decay of the activated material has a very short half-life of 5 s, which necessitates rapid data collection immediately following an experiment. In this regime, dead time can be very high (>50%) adding significant uncertainty to the measurement. To combat this, we have developed a dead time model that can self-consistently describe the measured data. Initial results show reasonable agreement (within 20%) with DD neutron yields from neutron time-of-flight spectrometers., (© 2025 Author(s). Published under an exclusive license by AIP Publishing.)

Background: While medications for opioid use disorder (MOUD) are effective in reducing overdoses, widespread adoption and implementation of MOUD remains inadequate. Innovative approaches to promote MOUD use and to support people in their medication-assisted recovery (MAR) are needed. Recovery residences that serve people taking MOUD are steadily growing in number, yet little is known about how MOUD and the MAR pathway is promoted within the recovery residence setting. Objectives: The purpose of this qualitative analysis was to describe how recovery residences facilitate MOUD initiation and support residents' MAR pathway. Methods: We conducted interviews with 93 residents (59.1% male; 38.7% female) living in recovery residences located in five Texas cities that served people taking medication for opioid use disorder. Results: We found that recovery residence staff addressed linkage to care gaps in their communities by connecting people who might benefit from MOUD to appropriate providers. Recovery residence staff also strengthened participants' community of MAR-supportive peers by hosting or connecting residents to Medication-Assisted Recovery Anonymous meetings. Additionally, recovery residences helped some residents overcome common logistical barriers (e.g. transportation issues, housing instability, distance to providers) that hinder MOUD access. Conclusion: Recovery residences that serve people taking MOUD are a well-positioned recovery support service to promote MOUD initiation and the MAR pathway.

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

Neutron-yield diagnostics at the NIF have been upgraded to include 48 detectors placed around the NIF target chamber to assess the DT-neutron-yield isotropy for inertial confinement fusion experiments. Real-time neutron-activation detectors are used to understand yield asymmetries due to Doppler shifts in the neutron energy attributed to hotspot motion, variations in the fuel and ablator areal densities, and other physics effects. In order to isolate target physics effects, we must understand the contribution due to neutron scattering associated with the different hardware configurations used for each experiment. We present results from several calibration experiments that demonstrate the ability to achieve our goal of 1% or better precision in determining the yield isotropy.

The Real Time Nuclear Activation Detector (RTNAD) array at NIF measures the distribution of 14 MeV neutrons emitted by deuterium-tritium (DT) fueled inertial confinement fusion implosions. The uniformity of the neutron distribution is an important indication of implosion symmetry and DT shell integrity. The array consists of 48 LaBr 3 (Ce) crystal gamma-ray spectrometers mounted outside the NIF target chamber, which continuously monitor the slow decay of the 909 keV gamma-ray line from activated 89 Zr located in Zr cups surrounding each crystal. The measured decay rate dramatically increases during a DT implosion in proportion to the number of 14 MeV neutrons striking each Zr cup. The neutrons produce activated 89 Zr through an (n, 2n) reaction on 90 Zr, which is insensitive to low energy neutrons. The neutron flux along the detector line-of-sight at shot time is determined by extrapolating the fitted 909 keV decay curve back to shot time. Automatic analysis algorithms were developed to handle the non-stop data stream. The large number of detectors and the high statistical accuracy of the array enable the spherical harmonic modes of the neutron angular distribution to be measured up to L ≤ 4 to provide a better understanding of implosion dynamics. In addition, these data combined with measurements of the down-scattered neutrons can be used to derive fuel areal density distributions. This paper will describe the RTNAD hardware and analysis procedures.

The on-going developments in laser acceleration of protons and light ions, as well as the production of strong bursts of neutrons and multi-[Formula: see text] photons by secondary processes now provide a basis for novel high-flux nuclear physics experiments. While the maximum energy of protons resulting from Target Normal Sheath Acceleration is presently still limited to around [Formula: see text], the generated proton peak flux within the short laser-accelerated bunches can already today exceed the values achievable at the most advanced conventional accelerators by orders of magnitude. This paper consists of two parts covering the scientific motivation and relevance of such experiments and a first proof-of-principle demonstration. In the presented experiment pulses of [Formula: see text] at [Formula: see text] duration from the PHELIX laser produced more than [Formula: see text] protons with energies above [Formula: see text] in a bunch of sub-nanosecond duration. They were used to induce fission in foil targets made of natural uranium. To make use of the nonpareil flux, these targets have to be very close to the laser acceleration source, since the particle density within the bunch is strongly affected by Coulomb explosion and the velocity differences between ions of different energy. The main challenge for nuclear detection with high-purity germanium detectors is given by the strong electromagnetic pulse caused by the laser-matter interaction close to the laser acceleration source. This was mitigated by utilizing fast transport of the fission products by a gas flow to a carbon filter, where the [Formula: see text]-rays were registered. The identified nuclides include those that have half-lives down to [Formula: see text]. These results demonstrate the capability to produce, extract, and detect short-lived reaction products under the demanding experimental condition imposed by the high-power laser interaction. The approach promotes research towards relevant nuclear astrophysical studies at conditions currently only accessible at nuclear high energy density laser facilities.

Manganese(iv) oxide (pyrolusite, birnessite) mineral amendments can reduce dissolved MeHg concentrations in sediment theoretically by inhibiting microbial sulfate reduction, which is a major methylation pathway in sediments. Anaerobic sediment slurry microcosms in which Hg methylation was stimulated by addition of labile organic carbon (acetate) and HgCl2 showed that manganese(iv) oxide reduced the percent MeHg in slurry porewater (filtered), by 1-2 orders of magnitude relative to controls. Sediment-water mesocosms with pyrolusite or birnessite either directly mixed into the top 5 cm or applied in a thin (5 cm) sand layer over sediment showed reductions in percent MeHg in porewater of 66-69% for pyrolusite and 81-89% for birnessite amendment. A thin sand layer alone resulted in 65% reduction. CO2 respirometry experiments showed that the amendments stimulated microbial activity. Microbial community census by PCR and DNA sequencing indicated that the addition of Mn(iv) oxides did not significantly alter the indigenous sediment microbial community structure, although a small increase in abundance of iron and manganese reducers was observed after a 2 week incubation period. The mechanism of decreasing MeHg relative to Hg concentrations in porewater likely involved an increase in the importance of Mn(iv) reduction (relative to sulfate reduction) in heterotrophic microbial metabolism in the sediments amended with Mn(iv) oxides. Manganese reduction was confirmed as the predominant biogeochemical redox process by microelectrode voltammetry profiling of the sediment microcosms, although adsorption to Mn oxide surfaces, enhanced MeHg demethylation, and abiotic reduction of Mn(iv) also may have been involved in reducing percent MeHg and suppressing net MeHg production. These results represent a novel approach for mitigating MeHg impacts from sediments with potential applicability to a range of aquatic settings including intertidal zones, tidal marshes, seasonal wetlands, reservoirs, and lakes.

In situ amendment of sediments with highly sorbent materials like activated carbon (AC) is an increasingly viable strategy to reduce the bioavailability of persistent, sediment-associated contaminants to benthic communities. Because in situ sediment remediation is an emerging strategy, much remains to be learned about the field conditions under which amendments can be effective, the resilience of amendment materials toward extreme weather conditions, and the optimal design of engineered applications. We report the results of a multiyear, pilot-scale field investigation designed to measure the persistence and efficacy of AC amendments to reduce the bioavailability of polychlorinated biphenyls (PCBs) in an intertidal Phragmites marsh. The amendments tested were granular AC (GAC), GAC with a layer of sand, and a pelletized fine AC. Key metrics presented include vertically resolved black carbon concentrations in sediment and PCB concentrations in sediment, porewater, and several invertebrate species. The results demonstrate that all 3 amendments withstood Hurricane Sandy and remained in place for the duration of the study, successfully reducing porewater PCB concentrations by 34 to 97%. Reductions in invertebrate bioaccumulation were observed in all amendment scenarios, with pelletized fine AC producing the most pronounced effect. The present findings support the use of engineered AC amendments in intertidal marshes and can be used to inform amendment design, delivery, and monitoring at other contaminated sediment sites. Environ Toxicol Chem 2018;37:2496-2505. © 2018 SETAC., (© 2018 SETAC.)

Medical education in Chile has a good research productivity. National educators are skilled in complex curricular design processes and in didactic innovation. However, the question of what it means to be doctor in a society that moves towards interculturality, has not been addressed thoroughly. Using the structure of a clinical record, we outline our critical view about the relationship between medical education and diversity. To describe the medical history, we refer to some variables of the training process such as the Hegemonic Model of Medicine, the epistemological beliefs of the students, the hidden curriculum and the educational environment. Then, the empirical evidence of the clinical picture, diagnosis and internationally recommended treatment is described, to end with a local therapeutic proposal.

Background: The widespread growth of higher education is increasing the heterogeneity of university students in terms of socioeconomic characteristics, academic story and cultural background. Medical schools are not an exception of this phenomenon., Aim: To compare the academic background and self-directed learning behavior of students who entered to a public medial school between 2010 and 2014., Material and Methods: A non-probabilistic sample of 527 medical students aged between 17 and 29 years (60% men), was studied. Their academic information was collected from the University data base; they answered the Self-directed learning readiness scale of Fisher., Results: Students from the 2014 cohort had higher high school grades than their counterparts. The scores in mathematics of the Scholarship Aptitude Test (SAT) were higher in the cohorts of 2010 and 2011. Those of the sciences test were superior in the 2013 cohort. The 2014 cohort had the lower general score of self-directed learning behaviors., Conclusions: The lower SAT and self-directed learning scores of the students entering medical school in 2014, indicate the progressive increase in the heterogeneity of Medical students.

Management of Hg-contaminated sites poses particular challenges because methylmercury (MeHg), a potent bio-accumulative neurotoxin, is formed in the environment, and concentrations are not generally predictable based solely on total Hg (THg) concentrations. In this review, we examine the state of knowledge regarding the chemical, biological, and physical controls on MeHg production and identify those most critical for contaminated site assessment and management. We provide a list of parameters to assess Hg-contaminated soils and sediments with regard to their potential to be a source of MeHg to biota and therefore a risk to humans and ecological receptors. Because some measurable geochemical parameters (e.g., DOC) can have opposing effects on Hg methylation, we recommend focusing first on factors that describe the potential for Hg bio-accumulation: site characteristics, Hg and MeHg concentrations, Hg availability, and microbial activity, where practical. At some sites, more detailed assessment of biogeochemistry may be required to develop a conceptual site model for remedial decision making. Integr Environ Assess Manag 2017;13:249-263. © 2016 SETAC., (© 2016 SETAC.)

Opinions about marijuana use in the United States are becoming increasingly favorable, making it important to understand how psychosocial influences impact individuals' use in this context. Here, we used the theory of planned behavior to examine the influence of initial attitudes, norms, and efficacy to resist use on initial intentions and then to examine the effect of initial intentions on actual marijuana use measured 1 year later using data drawn from a community with relatively high use. We expanded the traditional theory of planned behavior model by investigating 2 types of normative influence (descriptive and injunctive) and 2 types of intentions (use intentions and proximity intentions), reasoning that exposure to high use in the population may produce high descriptive norms and proximity intentions overall, but not necessarily increase actual use. By contrast, we expected greater variability in injunctive norms and use intentions and that only use intentions would predict actual use. Consistent with hypotheses, intentions to use marijuana were predicted by injunctive norms (and attitudes) and in turn predicted marijuana use 1 year later. By contrast, descriptive norms were relatively high among all participants and did not predict intentions. Moreover, proximity intentions were not predictive of actual use. We also found that increasing intentions to use over a 1-year period predicted greater use. Given the greater efficacy of theory-based as compared with non-theory-based interventions, these findings provide critical information for the design of successful interventions to decrease marijuana-associated harms., ((c) 2015 APA, all rights reserved).)

A new radiochemical method for determining deuterium-tritium (DT) fuel and plastic ablator (CH) areal densities (ρR) in high-convergence, cryogenic inertial confinement fusion implosions at the National Ignition Facility is described. It is based on measuring the (198)Au/(196)Au activation ratio using the collected post-shot debris of the Au hohlraum. The Au ratio combined with the independently measured neutron down scatter ratio uniquely determines the areal densities ρR(DT) and ρR(CH) during burn in the context of a simple 1-dimensional capsule model. The results show larger than expected ρR(CH) values, hinting at the presence of cold fuel-ablator mix.

We describe a radiochemical measurement of the ratio of isotope concentrations produced in a gold hohlraum surrounding an Inertial Confinement Fusion capsule at the National Ignition Facility (NIF). We relate the ratio of the concentrations of (n,γ) and (n,2n) products in the gold hohlraum matrix to the down-scatter of neutrons in the compressed fuel and, consequently, to the fuel's areal density. The observed ratio of the concentrations of (198m+g)Au and (196g)Au is a performance signature of ablator areal density and the fuel assembly confinement time. We identify the measurement of nuclear cross sections of astrophysical importance as a potential application of the neutrons generated at the NIF.

Substance cue reactivity is theorized as having a significant role in addiction processes, promoting compulsive patterns of drug-seeking and drug-taking behavior. However, research extending this phenomenon to cannabis has been limited. To that end, the goal of the current work was to examine the relationship between cannabis cue reactivity and craving in a sample of 353 participants varying in self-reported cannabis use. Participants completed a visual oddball task whereby neutral, exercise, and cannabis cue images were presented, and a neutral auditory oddball task while event-related brain potentials (ERPs) were recorded. Consistent with past research, greater cannabis use was associated with greater reactivity to cannabis images, as reflected in the P300 component of the ERP, but not to neutral auditory oddball cues. The latter indicates the specificity of cue reactivity differences as a function of substance-related cues and not generalized cue reactivity. Additionally, cannabis cue reactivity was significantly related to self-reported cannabis craving as well as problems associated with cannabis use. Implications for cannabis use and addiction more generally are discussed.

Background: Numerous studies have shown that attention deficit/hyperactivity disorder (ADHD) is associated higher risk of cannabis use disorders (CUD). However, these studies are limited in that most did not: (a) differentiate the role of hyperactivity-impulsivity (HI) and inattention (IN); (b) control for associated psychopathology; and (c) consider more fine-grained CUD-related measures. Our aim was to clarify the unique and interactive contributions of inattention and hyperactivity symptoms to age of cannabis initiation and DSM-IV cannabis dependence, craving, and severity of problems related to cannabis use while statistically controlling for symptoms of comorbid psychopathology in a non-clinical sample of young adults., Methods: Cannabis variables, current use of cigarettes and alcohol, current and childhood ADHD, and comorbid internalizing and externalizing psychopathology were assessed in 376 male and female undergraduates., Results: Results indicate that current and childhood IN were independently associated with more severe cannabis use, craving, and problem use-related outcomes in young adulthood (p's<.01) and that childhood HI symptoms were associated with earlier initiation of cannabis (p<.01). Further, current IN symptoms moderated the relationships between level of use and more severe outcomes (p's<.01), such that higher IN strengthened positive associations among use and problem cannabis use. Associations with ADHD symptom dimensions and current use of alcohol and cigarettes were also present., Conclusions: Thus, current and childhood inattention symptoms as well as childhood hyperactive-impulsive symptoms emerged as significant factors in cannabis-related outcomes in young adults, even after statistically controlling for important confounding variables., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Alcohol is known to impair self-regulatory control of behavior, though mechanisms for this effect remain unclear. Here, we tested the hypothesis that alcohol's reduction of negative affect (NA) is a key mechanism for such impairment. This hypothesis was tested by measuring the amplitude of the error-related negativity (ERN), a component of the event-related brain potential (ERP) posited to reflect the extent to which behavioral control failures are experienced as distressing, while participants completed a laboratory task requiring self-regulatory control. Alcohol reduced both the ERN and error positivity (Pe) components of the ERP following errors and impaired typical posterror behavioral adjustment. Structural equation modeling indicated that effects of alcohol on both the ERN and posterror adjustment were significantly mediated by reductions in NA. Effects of alcohol on Pe amplitude were unrelated to posterror adjustment, however. These findings indicate a role for affect modulation in understanding alcohol's effects on self-regulatory impairment and more generally support theories linking the ERN with a distress-related response to control failures., (PsycINFO Database Record (c) 2012 APA, all rights reserved.)

Purpose/objectives: To determine the feasibility and effectiveness of implementing an in-home expressive-writing intervention among breast cancer survivors living in urban and rural areas., Design: Women who had completed radiation therapy were selected to participate in either expressive writing or a usual-care control condition., Setting: All materials were completed in the privacy of participants' homes., Sample: Of the 57 breast cancer survivors recruited, 40 participated in the writing intervention. An additional 40 women were assigned to the control group., Methods: Participants completed measures of physical and psychological health at two time points prior to writing and at two follow-up time points three and nine months after writing., Main Research Variables: Participation rates and physical and psychological health., Findings: Results showed that engaging in a single in-home writing session for women with breast cancer was feasible and showed significant improvements in physical and psychological health compared to control three months (but not nine months) after writing. Although no difference was found in effectiveness of the intervention between women living in urban versus rural areas, rural women showed slightly higher participation rates., Conclusions: The results illustrate the utility of employing remotely administered expressive-writing interventions for breast cancer survivors., Implications for Nursing: Healthcare professionals who wish to use writing to facilitate improvements in their patients may suggest that patients write at multiple time points, offer for the intervention to be completed at home, and target rural populations in particular.

Models of racial attitudes traditionally have assumed that individual differences in the strength of underlying, 'implicit' associations between racial categories and stereotypical traits are the primary determinant of the expression of race bias. Thus, individual differences in performance on laboratory tasks designed to assess implicit race bias tend to be interpreted in terms of association strength. Here, we argue that such associations tell only part of the story, and probably the least interesting part. We posit that response conflict and its regulation are critical to understanding the need for control, and that affect-related processes help to determine the extent to which control resources will be implemented to overcome biased associations. We present data from a number of recent behavioral and psychophysiological studies in support of this idea, as well as conceptual accounts that point toward a model of race bias regulation that depends upon processes identified as important for regulation of thought, affect and action more generally.

Low sensitivity to the acute effects of alcohol is a known risk factor for alcoholism. However, little is known concerning potential information-processing routes by which this risk factor might contribute to increased drinking. We tested the hypothesis that low-sensitivity (LS) participants would show biased attention to alcohol cues, compared with their high-sensitivity (HS) counterparts. Participants performed a task in which alcoholic and nonalcoholic beverage cues were presented bilaterally followed by a target that required categorization by color. Response times were faster for targets appearing in alcohol-cued than non-alcohol-cued locations for LS but not for HS participants. Event-related potential markers of early attention orienting (P1 amplitude) and subsequent attention reorienting (ipsilateral invalid negativity amplitude) indicated preferential selective attention to alcohol-cued locations among LS individuals. Controlling for recent drinking and family history of alcoholism did not affect these patterns, except that among HS participants, relatively heavy recent drinking was associated with difficulty reorienting attention away from alcohol-cued locations. These findings suggest a potential information-processing bias through which low sensitivity could lead to heavy alcohol involvement.

Research has shown that thoughts of one's; own death (i.e. mortality salience; MS) increase aspects of intergroup bias. However, the extent to which MS influences neural activity underlying basic person perception processes has not been examined. In the current study, event-related brain potentials were used as measures of online attentional and evaluative processes as White participants categorized ingroup (White) and outgroup (Black) faces according to expression (happy vs angry) following either MS or a control induction. Results showed that MS affected the amplitude of the P2 and N2 components elicited by ingroup faces but had no effect on the processing of outgroup faces. Processing of angry ingroup relative to angry outgroup faces was pronounced in the MS condition, reflected both in N2 amplitude and in longer latency of the P3 component, suggesting heightened sensitivity to threats to positive ingroup. Overall, findings suggest that MS intensifies perception of social category features, primarily by enhancing processing of ingroup cues.

The accumulation of monomethyl mercury (CH3Hg+) in aquatic ecosystems is a redox sensitive process that is accelerated under sulfate-reducing conditions. While nitrate (NO3-) reduction is energetically favored over sulfate reduction, the influence of NO3 on the accumulation of CH3Hg+ has not been reported in the literature. We examined temporal and vertical patterns in redox constituents and CH3Hg+ concentrations in the hypolimnion of a dimictic lake, Onondaga Lake, prior to and following increases in NO3- inputs. Detailed water-column profiles and a long-term record revealed marked decreases in the accumulation of CH3Hg+ in the anoxic hypolimnion coinciding with long-term decreases in the deposition of organic matter coupled with recent increases in NO3-concentrations. CH3Hg+ concentrations in the hypolimnion were substantially abated when No3 was present above the sediment-water interface. A decrease in the peak hypolimnetic mass of CH3Hg+ and shortening of the period of elevated CH3Hg+ concentrations resulted in more than a 50% decline in the accumulated CH3Hg+. N03- regulation of CH3Hg+ accumulation may be a widespread phenomenon in oxygen-limited freshwater and terrestrial environments, and could have an important notpreviously recognized, effect on the biogeochemistry of mercury.

Although alcoholics and individuals at risk for alcoholism often show smaller amplitude of the P3 event-related brain potential (ERP), recent data (K. Namkoong, E. Lee, C. H. Lee, B. O. Lee, & S. K. An, 2004) indicate that alcohol-related cues elicit larger P3 amplitude in alcoholics than in controls. Little is known concerning the ERP profiles or alcohol cue reactivity of social drinkers at risk for alcoholism due to low sensitivity to alcohol's effects. Participants differing in alcohol sensitivity viewed images of alcoholic and nonalcoholic beverages while ERPs were recorded and provided information about their alcohol use patterns at baseline and 4 months later. Compared to high-sensitivity participants, those low in sensitivity showed larger P3s to alcohol cues, even when recent alcohol use was statistically controlled for. Moreover, the P3 elicited by alcohol cues predicted alcohol use at follow-up, a finding supporting the idea that P3 amplitude reflects the motivational significance of substance-related cues. These findings point to risk status, not consumption history, as an important predictor of cue reactivity effects.

An intense collimated beam of high-energy protons is emitted normal to the rear surface of thin solid targets irradiated at 1 PW power and peak intensity 3x10(20) W cm(-2). Up to 48 J ( 12%) of the laser energy is transferred to 2x10(13) protons of energy >10 MeV. The energy spectrum exhibits a sharp high-energy cutoff as high as 58 MeV on the axis of the beam which decreases in energy with increasing off axis angle. Proton induced nuclear processes have been observed and used to characterize the beam.