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Jupiter was observed in the aftermath of its impact with fragment R of Comet Shoemaker-Levy/9 to search for seismic waves excited by the collision. Observations were made in the 7.8 [[micro]meter] methane emission band with the MIRAC2 camera at the IRTF in an attempt to detect the local perturbation to the equilibrium stratospheric temperature profile induced by the wave. Detection of a jovian seismic wave would provide the tightest constraint to date on interior models of Jupiter. Seismic waves were detected in neither direct images of the planet nor in a composite time-distance diagram which utilizes all of the available imagery. This non-detection allows us to place an upper limit on the energy of the fragment R impact of 1 x [10.sup.28] erg, assuming a seismic wave excitation efficiency of 15%.

Summary: New tuberculosis drug regimens are creating new priorities for drug susceptibility testing (DST) and surveillance. To minimise turnaround time, rapid DST will need to be prioritised, but developers of these assays will need better data about the molecular mechanisms of resistance. Efforts are underway to link mutations with drug resistance and to develop strain collections to enable assessment of new diagnostic assays. In resource-limited settings, DST might not be appropriate for all patients with tuberculosis. Surveillance data and modelling will help country stakeholders to design appropriate DST algorithms and to decide whether to change drug regimens. Finally, development of practical DST assays is needed so that, in countries where surveillance and modelling show that DST is advisable, these assays can be used to guide clinical decisions for individual patients. If combined judiciously during both development and implementation, new tuberculosis regimens and new DST assays have enormous potential to improve patient outcomes and reduce the burden of disease. [ABSTRACT FROM AUTHOR]

Purpose: Existing research on criminal justice contact data has not adequately examined the quality of self-reported timing data, has produced discrepant findings on validity as it relates to demographics, and is limited in its assessment of data quality using a life event calendar method. The study described in this article assessed the validity of self-reported contacts with the criminal justice system gathered using a life event calendar with a sample of incarcerated men. Methods: Self-reports of criminal justice contacts (i.e., arrests, jail terms, prison terms) were obtained from over 700 incarcerated men using a structured life-event calendar method. Similarly, data were collected from the inmate's official records for the same events. These reports served as an external criterion for the self-reports. Results: Results indicated a significant degree of reporting errors for arrests using the life event calendar approach with better reporting for jail and prison terms. Additionally, individuals with the highest number of previous arrests had the greatest recall difficulties. Conclusions: Recall of arrest presents a difficult recall task. The life event calendar method should either be modified to improve recall of specific events for criminological samples or used instead to capture information on more general and extended events. [Copyright &y& Elsevier]

Over twenty-five years of policy and scholarly attention to the problem of intimate partner violence appears to have generated greater victim safety. Intimate partner homicides, the most serious form of violence between intimates, have been declining for nearly three decades in many contexts, but not all. This study built on a small number of studies that had advanced knowledge about the policy-relevant factors behind the intimate partner homicide decline. The analysis described here utilized a set of county-level data from California from 1987 to 2000 to estimate the effects of shelter-based service availability on race/ethnicity-specific female intimate partner homicide victimization. The study relied on a new measure of service availability in an attempt to overcome limitations with previously used indicators. This analysis did not reveal an effect of shelter-based service availability and criminal justice system responses on changes in female intimate partner homicide victimizations. Reasons for these findings and suggestions for future research are discussed. [Copyright &y& Elsevier]

The public''s perception of the police is important because it is linked to several important outcomes, including compliance and cooperation with police. Long recognized as being important, research has investigated the factors associated with citizens'' evaluations of the police. The way police do their jobs, in addition to what they accomplish, has recently emerged as being a significant determinant of citizens'' evaluations of police. What remains largely unexamined is whether this relationship varies across distinct types of contacts between the police and citizens. The current study estimated the effects of citizens'' perceptions of procedural justice on overall ratings of officer performance across three types of police–citizen encounters. Results showed that procedurally fair treatment is the most important predictor of citizens'' evaluations. [Copyright &y& Elsevier]

Rationale and Objectives. To examine a statistical validation method based on the spatial overlap between two sets of segmentations of the same anatomy.Materials and Methods. The Dice similarity coefficient (DSC) was used as a statistical validation metric to evaluate the performance of both the reproducibility of manual segmentations and the spatial overlap accuracy of automated probabilistic fractional segmentation of MR images, illustrated on two clinical examples. Example 1: 10 consecutive cases of prostate brachytherapy patients underwent both preoperative 1.5T and intraoperative 0.5T MR imaging. For each case, 5 repeated manual segmentations of the prostate peripheral zone were performed separately on preoperative and on intraoperative images. Example 2: A semi-automated probabilistic fractional segmentation algorithm was applied to MR imaging of 9 cases with 3 types of brain tumors. DSC values were computed and logit-transformed values were compared in the mean with the analysis of variance (ANOVA).Results. Example 1: The mean DSCs of 0.883 (range, 0.876–0.893) with 1.5T preoperative MRI and 0.838 (range, 0.819–0.852) with 0.5T intraoperative MRI (P <.001) were within and at the margin of the range of good reproducibility, respectively. Example 2: Wide ranges of DSC were observed in brain tumor segmentations: Meningiomas (0.519–0.893), astrocytomas (0.487–0.972), and other mixed gliomas (0.490–0.899).Conclusion. The DSC value is a simple and useful summary measure of spatial overlap, which can be applied to studies of reproducibility and accuracy in image segmentation. We observed generally satisfactory but variable validation results in two clinical applications. This metric may be adapted for similar validation tasks. [Copyright &y& Elsevier]

Using data collected from a sample of cases associated with untested sexual assault kits (SAKs), we used focal concerns theory – a framework that identifies themes relevant to criminal justice practitioners' decision-making processes – to assess the correlates of suspect identification and officers' pre-arrest decision to present a case to prosecutors. We estimated two logistic regression models. The first model examined the ability of investigators to identify a suspect in the full sample (N = 444). The second model examined officers' decision to present cases to the prosecutor in a subsample of cases in which a suspect was identified (N = 293). The odds of suspect identification increased when victims cooperated with investigators and witnesses were available, and decreased in stranger cases and when victim credibility concerns were present in police reports. Cases were more likely to be presented to a prosecutor when victims cooperated with police, witnesses were available, suspects confessed to the crime, and suspects had a history of arrest. Researchers should continue to examine pre-arrest investigative actions to inform policy and training aimed at enhancing victim engagement and reducing case attrition. Additionally, SAKs should be tested to aid investigators in identifying suspects in stranger cases. • The chances of suspect identification and case advancement increased when officers believed victims were cooperating. • Results revealed mixed support for the utility of the focal concerns framework in understanding police investigative steps. • To enhance victim engagement with the criminal legal system, police investigators should be trained to effectively engage with and respond to victims. [ABSTRACT FROM AUTHOR]

The trace metal content of roots of samples of the American ginseng natural herbal plant species (Panax quinquefolius) was investigated as a means of differentiating between this species grown on Wisconsin and New Zealand farms, and from Canadian and Chinese sources. ICP-MS measurements were undertaken by ashing samples of the roots and then digestion with conc. HNO3 and H2O2. There was considerable variation in the concentrations of 28 detectable elements along the length of a root, between different roots, between different farms/sources and between different countries. Statistical processing of the log-transformed concentration data was undertaken using principal component analysis (PCA) and discriminant function analysis (DFA). Although PCA showed some differentiation between samples, a much clearer discrimination of the Panax quinquefolius species of ginseng from the four countries was observed using DFA. 88% of the variation between countries could be accounted for by only using discriminant function 1 while 80% of the remaining 12% of the variation between countries is accounted for by discriminant function 2. The Fisher Classification Functions classify 98% of the 87 samples to the correct country of origin with 97% of the cross-validated cases correctly classified. The predictive ability of this DFA model was further tested by constructing 100 discriminant models each using a random selection of the data for two thirds of the 87 sampled ginseng root tops, and then using the resulting classification functions to determine correctly the country of origin of the remaining third of the cases. The mean success rate of the 100 classifications was 92%. These results suggest that measurement and statistical analysis of just the trace metal content of the roots of Panax quinquefolius promises to be an excellent predictor of the country of origin of this ginseng species. [ABSTRACT FROM AUTHOR]

Abstract: We recently developed a functional neuroimaging technique called encephalographic magnetic resonance imaging (eMRI). Our method acquires rapid single-shot gradient-echo echo-planar MRI (repetition time=47 ms); it attempts to measure an MR signal more directly linked to neuronal electromagnetic activity than existing methods. To increase the likelihood of detecting such an MR signal, we recorded concurrent MRI and scalp electroencephalography (EEG) during fast (20–200 ms), localized, high-amplitude (>50 μV on EEG) cortical discharges in a cohort of focal epilepsy patients. Seen on EEG as interictal spikes, these discharges occur in between seizures and induced easily detectable MR magnitude and phase changes concurrent with the spikes with a lag of milliseconds to tens of milliseconds. Due to the time scale of the responses, localized changes in blood flow or hemoglobin oxygenation are unlikely to cause the MR signal changes that we observed. While the precise underlying mechanisms are unclear, in this study, we empirically investigate one potentially important confounding variable — motion. Head motion in the scanner affects both EEG and MR recording. It can produce brief “spike-like” artifacts on EEG and induce large MR signal changes similar to our interictal spike-related signal changes. In order to explore the possibility that interictal spikes were associated with head motions (although such an association had never been reported), we had previously tracked head position in epilepsy patients during interictal spikes and explicitly demonstrated a lack of associated head motion. However, that study was performed outside the MR scanner, and the root-mean-square error in the head position measurement was 0.7 mm. The large inaccuracy in this measurement therefore did not definitively rule out motion as a possible signal generator. In this study, we instructed healthy subjects to make deliberate brief (<500 ms) head motions inside the MR scanner and imaged these head motions with concurrent EEG and MRI. We compared these artifactual MR and EEG data to genuine interictal spikes. While per-voxel MR and per-electrode EEG time courses for the motion case can mimic the corresponding time courses associated with a genuine interictal spike, head motion can be unambiguously differentiated from interictal spikes via scalp EEG potential maps. Motion induces widespread changes in scalp potential, whereas interictal spikes are localized and have a regional fall-off in amplitude. These findings make bulk head motion an unlikely generator of the large spike-related MR signal changes that we had observed. Further work is required to precisely identify the underlying mechanisms. [Copyright &y& Elsevier]

Graphical abstract Highlights • An uncertainty-aware asynchronous scattered motion interpolation method is proposed. • The method uses non-constant-mean anisotropic-covariance Gaussian process regression. • The motion measurements are defined using a novel motion field representation. • The method outperforms the state-of-the-art Gaussian process regression models. • The method allows for uncertainty-aware registration of soft-tissue navigation data. Abstract We address the problem of interpolating randomly non-uniformly spatiotemporally scattered uncertain motion measurements, which arises in the context of soft tissue motion estimation. Soft tissue motion estimation is of great interest in the field of image-guided soft-tissue intervention and surgery navigation, because it enables the registration of pre-interventional/pre-operative navigation information on deformable soft-tissue organs. To formally define the measurements as spatiotemporally scattered motion signal samples, we propose a novel motion field representation. To perform the interpolation of the motion measurements in an uncertainty-aware optimal unbiased fashion, we devise a novel Gaussian process (GP) regression model with a non-constant-mean prior and an anisotropic covariance function and show through an extensive evaluation that it outperforms the state-of-the-art GP models that have been deployed previously for similar tasks. The employment of GP regression enables the quantification of uncertainty in the interpolation result, which would allow the amount of uncertainty present in the registered navigation information governing the decisions of the surgeon or intervention specialist to be conveyed. [ABSTRACT FROM AUTHOR]