Two experiments were conducted to establish responses in milk Se concentrations in grazing dairy cows to different amounts of dietary Se yeast, and to determine the effects of the Se concentration of ...the basal diet. The hypothesis tested was that the response in milk, blood, and tissue Se concentrations to supplemental Se would not be affected by whether the Se was from the basal diet or from Se yeast. In addition, by conducting a similar experiment in either early (spring; experiment 1) or late (autumn; experiment 2) lactation, we hypothesized that different Se input-output relationships would result. Both 6-wk experiments involved 60 multiparous Holstein-Friesian cows, all of which had calved in spring. They were allocated to 1 of 10 dietary Se treatments that included 2 types of crushed triticale grain (low Se, approximately 165μ g of Se/kg of DM; or high Se, approximately 580μ g/kg of DM) fed at 4kg of DM/d, and 1kg of DM/d of pellets formulated to carry 5 quantities of Se yeast (0, 4, 8, 12, or 16mg of Se). Daily total Se intakes ranged from <2 to >18 mg/cow in both experiments. Milk Se concentrations plateaued after 15 and 7 d of supplementation in experiments 1 and 2, respectively, and then remained at plateau concentrations. Average milk Se concentrations for the plateau period increased as the amount of Se yeast increased, and low- and high-Se grain treatments were different at all quantities of Se yeast, although there was a tendency for this difference to diminish at the greatest concentrations of yeast. There were significant positive, linear relationships between Se intake and the concentrations of Se in milk, which were not affected by the source of Se, and the relationships were similar for both experiments. Therefore, the output of Se in milk in experiment 1 was greater than that in experiment 2 because the milk yield of the cows in early lactation was greater. The estimated proportions of Se partitioned to destinations other than milk and feces increased with the amount of Se in the diet and were greater in experiment 2 than in experiment 1, a result that was supported by Se concentrations in whole blood and plasma and in semitendinosus muscle tissue. If high-Se products are to be produced for human nutrition, it is important to be able to develop feeding systems that produce milk with consistent and predictable Se concentrations so that products can consistently meet specifications. The results indicate that this objective is achievable.
Seventy multiparous Holstein-Friesian cows were fed different amounts of pasture and concentrates, or a total mixed ration (TMR), for 42 d in mid-lactation to test the hypothesis that the ...concentration of Se in milk would depend on the amount of Se consumed, when the Se is primarily organic in nature, regardless of the diet of the cows. Of the 70 cows, 60 grazed irrigated perennial pasture at daily allowances of either 20 or 40kg of dry matter (DM)/cow. These cows received 1 of 3 amounts of concentrates, either 1, 3, or 6kg of DM/cow per day of pellets, and at each level of concentrate feeding, the pellets were formulated to provide 1 of 2 quantities of Se from Se yeast, either about 16 or 32mg of Se/d. The other 10 cows were included in 2 additional treatments where a TMR diet was supplemented with 1kg of DM/d of pellets formulated to include 1 of the 2 quantities of supplemental Se. Total Se intakes ranged from 14.5 to 35.9 mg/d, and of this, the Se-enriched pellets provided 93, 91, and 72% of the Se for cows allocated 20 and 40kg of pasture DM/d or the TMR, respectively. No effects of the amount of Se consumed on any milk production variable, or on somatic cell count, body weight, and body condition score, for either the pasture-fed or TMR-fed cows were found. Milk Se concentrations responded quickly to the commencement of Se supplementation, reaching 89% of steady state levels at d 5. When milk Se concentrations were at steady state (d 12 to 40), each 1mg of Se eaten increased the Se concentration of milk by 5.0 μg/kg (R2=0.97), and this response did not seem to be affected by the diet of the cows or their milk production. The concentration of Se in whole blood was more variable than that in milk, and took much longer to respond to change in Se status, but it was not affected by diet at any time either. For the on-farm production of Se-enriched milk, it is important to be able to predict milk Se concentration from Se input. In our study, type of diet did not affect this relationship.
Indigenous peoples are overrepresented in correctional systems internationally, reflecting a history of systemic racism and colonial oppression, and the practice of risk assessment with this ...population has been a focus of legal and sociopolitical controversy. We conducted a systematic review and meta-analysis of the risk assessment literature comparing Indigenous and non-Indigenous (White majority) groups. We retrieved 91 studies featuring 22 risk tools and 15 risk/need/cultural domains (N = 59,693, Indigenous; N = 237,729, non-Indigenous/White) and four documents identifying culturally relevant factors. Most measures demonstrated moderate predictive validity but often had significant ethnoracial differences, particularly for static measures. The Service Planning Instrument/Youth Assessment Screening Inventory, Level of Service Inventory youth variants, Psychopathy Checklist-Revised and Youth Version, and the Violence Risk Scale and its Sexual Offense version had the strongest predictive validity and least ethnoracial discrepancy. The Static Factors Assessment and Dynamic Factors Identification and Analysis-Revised had the weakest predictive validity. For Indigenous persons, the strongest individual predictors of recidivism were low education/employment, substance abuse, antisocial pattern, and poor community functioning, while mitigating factors that predicted decreased recidivism were measures of risk change (i.e., from culturally integrated programs combining mainstream and traditional healing approaches), cultural engagement/connectedness, and protective factors. In practice, static measures need to be supplemented with dynamic ones, and assessors should select measures with at least moderate predictive validity and ideally the least ethnoracial bias. These conclusions are tempered by the quantity and quality of the literature coupled with the circumstance that some study authors have coauthored tools in this review.
Public Significance Statement
Most risk assessment measures can predict reoffending with a reasonable (i.e., moderate) level of accuracy for Indigenous people undergoing risk assessments in the justice system; however, these measures often have better accuracy when used with non-Indigenous (and primarily White) clients, particularly static measures that are heavily based on criminal history. The "best" potential measures tend to be dynamic tools, as these have less prediction bias, can drive services, measure reductions in risk (e.g., with culturally integrated treatment programs), and inform release decisions and community supervision strategies. Of note, other unmeasured or non-risk-relevant factors (e.g., overpolicing, aggressive prosecution) can inflate recidivism estimates for Indigenous peoples and decrease predictive validity of risk measures, which should be considered when conducting risk assessments. Careful, critical examination of current risk measures and further research is necessary to increase fair, humane, and ethical use of these measures with Indigenous clients in forensic, correctional, and legal settings.
The present study examined the predictive properties of three youth forensic measures-the Violence Risk Scale-Youth Version (VRS-YV), Structured Assessment of Violence Risk in Youth (SAVRY), and the ...Structured Assessment of Protective Factors-Youth Version (SAPROF-YV)-in a diverse court-adjudicated sample of 257 youth referred for assessment and intervention services at an outpatient mental health facility, and followed up an average of 9.4 years in the community. Study measures were rated from court and clinical files, along with treatment participation, and recidivism outcome data were obtained from official criminal records. The three measures had strong interrater and convergent validity, and moderate to high predictive accuracy for violent, nonviolent, and general recidivism. The measures significantly predicted outcome across male, female, Indigenous, and non-Indigenous groups; however, prediction magnitudes showed some variability with respect to specific risk/protection domains and outcome types. Cox regression survival analyses demonstrated incremental predictive validity for each violence risk measure, but not protection measures, with respect to each of the three recidivism outcomes. Moreover, pre-/posttreatment measurements of change on the VRS-YV dynamic factors were significantly associated with decreased nonviolent recidivism, controlling for baseline risk and protection. Violence risk (VRS-YV) and protection (SAPROF-YV) scores have the potential to be integrated in meaningful ways to capture the potential risk-mitigating effects of protective factors. Implications for integrating risk, protection, and treatment change information in clinical-forensic service delivery to diverse and violent youth populations are discussed.
Public Significance Statement
The study demonstrates the dynamic predictive properties of the Violence Risk Scale-Youth Version-a violence risk assessment, intervention planning, and change evaluation tool for youth-and supports the dynamism of violence risk in a diverse sample of court-adjudicated youth. The research further demonstrates viable and systematic ways of integrating risk and protective factor information and has important implications for gender and ethnocultural responsivity in the assessment, treatment, and management of violence risk.
The current study examined the self-reported working alliance of men attending a high intensity sexual offense treatment program and its associations with psychopathy, sexual violence risk, treatment ...change, and recidivism, in a Canadian sample of 317 incarcerated men followed up an average of approximately 10 years post release. Working Alliance Inventory (WAI; Horvath & Greenberg, 1989) self-reported total, Task, Bond, and Goal scores were positively correlated with treatment related changes in risk, and inversely associated with Psychopathy Checklist-Revised (PCL-R; Hare, 1991; Wang & Hare, 2003) scores. The Affective facet of the PCL-R, representing the callous-unemotional features of the syndrome, uniquely predicted lower Bond and Goal scores controlling for the other facets. Cox regression survival analyses demonstrated that sexual violence risk predicted increased sexual recidivism while change predicted decreased sexual recidivism controlling for PCL-R total score; however, WAI scores (particularly the Goal component) were also unexpectedly associated with increased sexual recidivism. For violent recidivism, psychopathy, risk, and change incremented the prediction of general violence, while the WAI was not significantly associated with this outcome. A set of parallel analyses, stratified by Indigenous ethnocultural heritage, demonstrated some continuity, but also potential areas of difference, in substantive findings. Risk, need, responsivity implications of the working alliance for the treatment of high psychopathy correctional clientele, and how this may intersect with Indigenous heritage, are discussed.
SN 2001em: Not So Fast Schinzel, F. K; Taylor, G. B; Stockdale, C. J ...
The Astrophysical journal,
02/2009, Letnik:
691, Številka:
2
Journal Article
Recenzirano
Odprti dostop
SN 2001em, originally classified as type Ib/c, is a peculiar supernova. It was observed in the radio about two years after its optical detection, showing a rising radio flux with an optically thin ...spectral slope; it also displayed a large X-ray luminosity (~1041 erg s-1). Thus, it was suspected to harbor a decelerating (by then, mildly) relativistic jet pointing away from us. About three years after its discovery, the optical spectrum of SN 2001em showed a broad H alpha line, and it was therefore, reclassified as type IIn. Here, we constrain its proper motion and expansion velocity by analyzing four epochs of VLBI observations, extending to 5.4 years after the SN. The supernova is still unresolved 5.4 years after the explosion. For the proper motion, we obtain (23,000± 30,000) km s-1, while our 2 sigma upper limit on the expansion velocity is 6000 km s-1. These limits are somewhat tighter than those derived by Bietenholz & Bartel, and confirm their conclusion that late time emission from SN 2001em, a few years after the explosion, is not driven by a relativistic jet. VLA observations of the radio flux density, at 8.46 GHz, show a decay as t -1.23 ± 0.40 starting ~2.7 years after the SN. Collectively, the observations suggest interaction of the SN ejecta with a very dense circumstellar medium, though the implied opacity constraints still present a challenge.
The current investigation was a prospective field validity study examining the discrimination and calibration properties of a general risk-need tool (Level of Service Inventory–Saskatchewan Youth ...Edition LSI-Sk) in a diverse sample of 284 court adjudicated youths, rated by their youth workers on the measure and followed up an average of 9.3 years. The overall risk level and need total demonstrated moderate predictive accuracy for general, violent, and nonviolent recidivism in the aggregate sample, although area under the curve (AUC) magnitudes fluctuated among gender and Indigenous ethnocultural subgroups. Variability in AUC values for the measure’s eight criminogenic need domains further reflected greater salience of certain needs among subgroups. Finally, clinician rated level of gang involvement incrementally predicted recidivism to varying degrees after controlling for overall risk and need. Implications for responsible use of risk assessment tools as part of individualized and gender/ethnoculturally responsive risk assessment practices with youth are discussed.
We studied the growth of the shell-like radio structure of supernova SN 1993J in M 81 from September 1993 to October 2003 with very-long-baseline interferometry (VLBI) observations at the wavelengths ...of 3.6, 6, and 18 cm. We developed a method to accurately determine the outer radius (R) of any circularly symmetric compact radio structure such as SN 1993J. The source structure of SN 1993J remains circularly symmetric (with deviations from circularity under 2%) over almost 4000 days. We characterize the decelerated expansion of SN 1993J until approximately day 1500 after explosion with an expansion parameter m = 0.845±0.005 (R $\propto$ $t^{m})$. However, from that day onwards the expansion differs when observed at 6 and 18 cm. Indeed, at 18 cm, the expansion can be well characterized by the same m as before day 1500, while at 6 cm the expansion appears more decelerated, and is characterized by another expansion parameter, m6 = 0.788±0.015. Therefore, since about day 1500 onwards, the radio source size has been progressively smaller at 6 cm than at 18 cm. These findings differ significantly from those of other authors in the details of the expansion. In our interpretation, the supernova expands with a single expansion parameter, m = 0.845±0.005, and the 6 cm results beyond day 1500 are caused by physical effects, perhaps also coupled to instrumental limitations. Two physical effects may be involved: (a) a changing opacity of the ejecta to the 6 cm radiation; and (b) a radial decrease of the magnetic field in the emitting region. We also found that at 6 cm about 80% of the radio emission from the backside of the shell behind the ejecta is absorbed (our average estimate, since we cannot determine any possible evolution of the opacity), and the width of the radio shell is (31±2)% of the outer radius. The shell width at 18 cm depends on the degree of assumed absorption. For 80% absorption, the width is (33.5±1.7)%, and for 100% absorption, it is (37.8±1.3)%. A comparison of our VLBI results with optical spectral line velocities shows that the deceleration is more pronounced in the radio than in the optical. This difference might be due to a progressive penetration of ejecta instabilities into the shocked circumstellar medium, as also suggested by other authors.
Risk Assessment With Young Offenders Olver, Mark E.; Stockdale, Keira C.; Wormith, J. Stephen
Criminal justice and behavior,
04/2009, Letnik:
36, Številka:
4
Journal Article
Recenzirano
The current investigation is a meta-analysis of the predictive accuracy of three well-known forensic instruments used to appraise risk with young offenders: youth adaptations of the Level of Service ...Inventory and Psychopathy Checklist and the Structured Assessment of Violence Risk for Youth. Through several avenues, 49 potentially suitable published and unpublished studies (across 44 samples representing 8,746 youth) were identified and evaluated for inclusion. Predictive accuracy for general, nonviolent, violent, and sexual recidivism was examined for the three sets of measures. Mean weighted correlations for each of the three measures were significant in the prediction of general, nonviolent, and violent recidivism, with no single instrument demonstrating superior prediction. Separate analyses of specific young offender groups further supported the predictive accuracy of youth adaptations of the Level of Service Inventory among male, female, Aboriginal, and non-Aboriginal youth. Implications regarding the utility of young offender risk measures for enhancing clinical service provision with youth clientele are discussed.
► The perceived duration of visual stimuli varies with spatial frequency content. ► Subjective time expansion in response to oddball stimuli is not a general result. ► Sounds being perceived as ...longer than visual stimuli is not a general result.
We investigated whether changes in low-level image characteristics, in this case spatial frequency, were capable of generating a well-known expansion in the perceived duration of an infrequent “oddball” stimulus relative to a repeatedly-presented “standard” stimulus. Our standard and oddball stimuli were Gabor patches that differed from each other in spatial frequency by two octaves. All stimuli were equated for visibility. Rather than the expected “subjective time expansion” found in previous studies, we obtained an equal and opposite expansion or contraction of perceived time dependent upon the spatial frequency relationship of the standard and oddball stimulus. Subsequent experiments using equi-visible stimuli reveal that mid-range spatial frequencies (ca. 2c/deg) are consistently perceived as having longer durations than low (0.5c/deg) or high (8c/deg) spatial frequencies, despite having the same physical duration. Rather than forming a fixed proportion of baseline duration, this bias is constant in additive terms and implicates systematic variations in visual persistence across spatial frequency. Our results have implications for the widely cited finding that auditory stimuli are judged to be longer in duration than visual stimuli.
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