Questions, propositions and assessing different levels of evidence: Forensic voice comparison in practice.

This paper contributes to the ongoing discussion about the distinction between observations and propositions in forensic inference, with a specific focus on forensic voice comparison casework conducted in the UK. We outline both linguistic and legal issues which make the evaluation of voice evidence and the refinement of propositions problematic in practice, and illustrate these using case examples. We will argue that group-level observations from the offender sample will always be evidential and that the value of this evidence must be determined by the expert. As such, a proposal is made that experts should, at least conceptually, think of voice evidence as having two levels, both with evidential value: group-level and individual-level. The two rely on different underlying assumptions, and the group-level observations can be used to inform the individual-level propositions. However, for the sake of interpretability, it is probably preferable to present only one combined conclusion to the end user. We also wish to reiterate points made in previous work: in providing conclusions, the forensic expert must acknowledge that the value of the evidence is dependent on a number of assumptions (propositions and background information) and these assumptions must be made clear and explicit to the user.

Analysis of the relationship between hip joint flexion/extension and torques in the mark III space suit using a computational dynamics model.

Advanced SSAs (e.g., the Mark III (MKIII)) were designed to increase mobility by eliminating the volume change associated with bending joints by using constant-volume rigid components with bearings connecting these components. Even with these changes, there are added torques required by the operator to drive the motion, which increases the energy expenditure with respect to unsuited motion. Part of the added effort stems from the mass and inertia of the suit, as well as frictional resistances to motion. This research considers the relationship between joint torques that an operator must generate and the resulting flexion/extension of the hip bearing assembly. A computational dynamics model of the MKIII inclusive of inertial and bearing friction properties was created and sensitivities of the model to input parameters (e.g., applied force, direction of gravity, bearing friction magnitude, knee angle) were investigated. The model was configured to match previously collected benchtop experimental suit data without a human that was externally forced. The model captured the hysteretic behaviour and estimated about 80% of the mean hip angle range as compared to the experimental data. Decreasing bearing resistance increased alignment with the experimental data. The torque due to inertia and friction each had periods where they dominated the total torque, supporting the importance of minimizing both mass and bearing friction. The present effort also highlighted how external forces and boundary conditions affected peak hip flexion/extension. Future efforts can use these types of dynamics models to examine motions driven internally by a person to achieve specific motions.

Observational methods to measure behaviors of captive cotton-top tamarins (Saguinus oedipus).

The purpose of this study was to identify efficient sampling methods for establishing accurate activity budgets for zoo animals. Seven cotton-top tamarins (Saguinus oedipus) from two zoos were videotaped for multiple 90 min sessions, 3 to 4 days per week for 12 weeks. An activity budget was constructed for each animal using a continuous sampling method to analyze 30 hr of video recording of each animal. These master datasets, reflecting actual behavior, were re-sampled using interval sampling lengths of 0.25, 0.5, 1, 2, 4, 5, 7, 10, 15 and 20 min, and cluster sampling protocols (periodic sessions of continuous sampling) of 10 min x 3, 15 min x 2, 20 min x 1, 15 min x 1 and 10 min x 1 (min x repetitions/90 min sample period) to construct additional activity budgets for each animal. The Canberra similarity index was used to determine the statistical relationship between these activity budgets and those based on the master datasets. As interval length increased, there was a consequent decrease in the accuracy of the associated activity budgets as compared with the master dataset. No cluster sampling protocols yielded activity budgets as accurate as the four shortest interval lengths, but all cluster sampling protocols were more accurate than the three longest interval lengths. All the tested protocols varied in ability to accurately portray animal behavior. Overall, interval sampling provided superior behavioral representations at lower observer input. Results from this study will potentially facilitate the standardization of behavior monitoring protocols at zoos.

Mobility and Agility During Locomotion in the Mark III Space Suit.

INTRODUCTION: The Mark III (MIII) space suit assembly (SSAs) implements a multibearing, hard-material hip brief assembly (HBA). We hypothesize that: 1) the MIII HBA restricts operator mobility and agility which manifests in effects to gait parameters; 2) the waist bearing provides rotational motion, partially alleviating the restrictions; and 3) there are resistive, speed-dependent torques associated with the spinning bearings which further diminish mobility and agility. METHODS: A subject (Suited and Unsuited) performed two planetary tasks-walking forward (WF) and backward (WB). An analysis of variance (ANOVA) and post hoc comparisons were performed to determine interaction effects. Motion capture data was processed to obtain gait parameters: static base (m), dynamic base (m), step length (m), stride length (m), cadence (steps/min), center of mass speed (m · s-1), foot clearance (toe and heel) (m), and bearing angular velocities (° · s-1). RESULTS: The static base when Suited (0.355 m) was larger than Unsuited (0.263 m). The Suited dynamic base (pooled, 0.200 m) was larger than both Unsuited WF (0.081 m) and WB (0.107 m). When Suited, the operator had lower clearance heights. The waist bearings provided about 7.2° of rotation when WB and WF. The maximum torque, while WF, in the right upper and mid bearings was 15.6 ± 1.35 Nm and 16.3 ± 1.28 Nm. DISCUSSION: This study integrated suit component properties and the emergent biomechanics of the operator to investigate how biomechanics are affected. The human hip has three collocated degrees of freedom (DOFs), whereas the HBA has a single DOF per bearing. The results can inform requirements for future SSA and other wearable system designs and evaluations.Cullinane CR, Rhodes RA, Stirling LA. Mobility and agility during locomotion in the Mark III space suit. Aerosp Med Hum Perform. 2017; 88(6):589-596.

Dexamethasone responsive element in the rat Na, K-ATPase beta1 gene coding region.

The Na, K-ATPase plays an essential role in active alveolar epithelial fluid resorption. In fetal and adult alveolar epithelial cells, glucocorticoids (GC) increase Na, K-ATPase activity, mRNA levels, and transcription rate of the beta(1) subunit. In this study, we describe a glucocorticoid responsive element (GRE) in the coding region of the rat Na, K-ATPase beta(1) gene in a rat lung epithelial cell line. Transient transfection experiments with the beta(1) subunit coding region with or without the 5' and 3' untranslated regions demonstrated responsiveness to dexamethasone induction and also identified a GRE at +434 in exon IV. The +434 GRE conferred dexamethasone responsiveness in a heterologous thymidine kinase promoter irrespective of its orientation to the beta(1) promoter. Transcriptional upregulation by dexamethasone was abolished in +434 mutants. Electrophoretic mobility shift assays (EMSA) demonstrated specific binding of nuclear proteins to the +434 GRE and the presence of the GC receptor. This specific binding was inhibited by a GRE previously described in the rat Na, K-ATPase beta(1) gene at -631. In conclusion, we identified a GRE at +434 in the exon IV of the rat Na, K-ATPase beta(1) gene.

Epidemiologic investigation of seroprevalence of antibodies to Toxoplasma gondii in cats and rodents.

OBJECTIVE: To provide an epidemiologic investigation of the seroprevalence of antibodies to Toxoplasma gondii in populations of cats and wild rodents in Rhode Island and to address the possible epidemiologic role of wild rodents in the spread of toxoplasmosis. ANIMALS: 200 cats and 756 small wild rodents. PROCEDURE: Serum samples were obtained from 84 cats in animal shelters and 116 cats in veterinary hospitals. Serum samples were also obtained from 756 small wild rodents from multiple sites in Rhode Island. Sera from rodents and cats were assayed for antibodies to Tgondii by use of the modified agglutination test RESULTS: Overall, 42% (84/200) of cats had serum antibodies to Tgondii. Seroprevalence was not significantly different between stray (50%; 42/84) versus client-owned (36%; 42/116) cats, between male (43%; 40/94) versus female (42%; 39/93) cats, or between indoor (26%; 7/27) versus outdoor (39%; 35/89) cats. Seroprevalence rate of trapped rodents was 0.8% (6/756). Six rodents captured in Washington County accounted for of the seropositive rodents. Four of 6 of the seropositive rodents were trapped at a single site in Washington County (an abandoned barn). Five stray cats, known to have resided at the same site in Washington County as 4 of the seropositive rodents, were also found to be seropositive for antibodies to T gondii. CONCLUSIONS AND CLINICAL RELEVANCE: Seroprevalence rate in rodents was not correlated with the seroprevalence rate in cats. Stray cats, especially those known to be feral, may be more likely to perpetuate the cat-mouse cycle of T gondii than client-owned cats.

Stability of phenytoin sodium suspensions for the treatment of open wounds.

The objective of this study was to evaluate the stability of two phenytoin sodium suspensions in 0.9% sodium chloride solution for use in noninstitutional settings (where pharmacies are not present) to dispense phenytoin on a daily basis. A generic extended phenytoin sodium (Mylan) and a name brand phenytoin sodium (Dilantin) in suspension form were evaluated. Both suspensions were first assessed for degradation during frozen storage at designated time intervals. Frozen samples were compared with freshly prepared samples. The chemical stability of phenytoin concentration in the samples was assessed by using a high-performance liquid chromatography analytical technique. During the course of the experiment, the samples showed no crystallization and the pH remained in a range of 10.6 to 10.73. The suspensions were tested for contamination. The results show that Dilantin and Mylan suspensions remained stable and free of contamination. Suspensions of phenytoin sodium in 0.9% sodium chloride solution are stable at room temperature for at least 2 weeks.

Possible warfarin failure due to interaction with smokeless tobacco.

OBJECTIVE: To report a case of possible interaction of smokeless tobacco with warfarin in a patient treated after several thromboembolic events. CASE SUMMARY: A white man with a long history of smokeless tobacco use was unsuccessfully treated with warfarin up to 25-30 mg/day. International normalized ratio (INR) values never stabilized >2.0 over 4.5 years of therapy. This patient had experienced 3 myocardial infarctions (MIs) and 2 ischemic strokes between the ages of 29 and 31 years and experienced another MI at age 33 years. This was followed by several episodes of transient ischemic attacks at age 34 years. During the final year of warfarin treatment, tobacco use was terminated, followed by an increase in INR values from 1.1 to 2.3 within one week. Warfarin therapy was discontinued and smokeless tobacco use was reinstated and tapered slowly to discontinuation. Following warfarin discontinuation, ticlopidine therapy was initiated. Subsequently, this patient was placed on long-term clopidogrel therapy. Mechanisms responsible for this interaction have not been established, but would most likely involve an increased dietary source of vitamin K from tobacco. DISCUSSION: Tobacco contains high levels of vitamin K, and its use may have contributed directly to the failure of warfarin therapy to achieve therapeutic INR levels in this patient. An objective causality scale indicates a probable association between this combination and the adverse effects. Smokeless tobacco use should be charted in patients undergoing warfarin therapy, and patients who desire to stop tobacco use should be aided in this process. CONCLUSIONS: Possible health effects of smokeless tobacco may include potential drug interactions. These interactions may be based on pharmacodynamic and/or pharmacokinetic parameters involving any of the many pharmacologically active substituents of tobacco. Proposed mechanisms of drug interaction may include increased vitamin K levels in the diet.