Joining forces: Combining police and external expertise for cold case reviews.

Cold case reviews within police and law enforcement agencies are challenging, not the least owing to the amount of time required to carefully review documentation, forensic exhibit holdings and various other casefile information. Most federal and state agencies are time poor, meaning there are very few dedicated cold case teams fortunate enough to have an abundance of police and expert staff resources. Universities and education organisations, however, have large troves of various expertise, alongside expansive human resources, by way of their academic and student body.

Extended Reality Head-Mounted Displays Are Likely to Pose a Significant Risk in Medical Settings While Current Classification Remains as Non-Critical.

Extended reality (XR) devices, including virtual and augmented reality head-mounted displays (HMDs), are increasingly utilised within healthcare to provide clinical interventions and education. Currently, XR devices are utilised to assist in reducing pain and improving psychological outcomes for immunocompromised patients in intensive care units, palliative care environments and surgical theatres. However, there is a paucity of research on the risks of infection from such devices in healthcare settings.

A controlled method for the identification of forensic traces from clandestine grave fill.

Deceased human remains are often buried as a forensic countermeasure or method of disposal by homicide perpetrators. Owing to this, the excavation of clandestine grave sites is a task that forensic crime scene teams may only encounter a few times a year. Not all crime scene units have specialised teams for this task, and even those that do, may not have specific protocols for the optimal recovery of forensic traces retained within grave fill as procedures such as sieving require optimisation for the specific soil conditions of the jurisdiction.

The Sexome - A proof of concept study into microbial transfer between heterosexual couples after sexual intercourse.

The detection and recovery of male DNA post-assault is important in sexual assault investigations, particularly where an offender is unknown to the victim. The collection of DNA evidence often occurs when the female victim undergoes a forensic medical assessment. Analysis regularly results in mixed autosomal DNA profiles with both victim and perpetrator DNA, often making it difficult to interpret a male profile suitable for DNA database searching.

Finding the missing and unknown: Novel educational approaches to warming up cold cases.

In recent years, students in police academies and higher education institutions around the world have worked together to analyse cold cases including long-term missing persons cases in collaboration with investigators and prosecutors. In 2020, three European organisations, the Police Expert Network on Missing Persons (PEN-MP), AMBER Alert Europe and Locate International, succeeded in connecting these educational organisations enabling them to work collectively on cases and conduct cold case analyses (CCA) across international borders. The International Cold Case Analysis Project (ICCAP) learning objectives were to 1) collect the necessary information about the victim, 2) reconstruct the crime, and 3) investigate trace control.

Methods for ensuring the highest DNA concentration and yield in future and retrospective trace DNA extracts.

In forensic laboratories, increased extraction efficiency of trace evidence is paramount because analytical success is intrinsically dependent on the quantity of DNA recovered. Moreover, highly concentrated nucleic acids are vital for effective downstream analysis and high quality results. This study investigated the efficiency of extraction with the Qiagen® QIAamp® DNA Investigator kit, and explored improvements to the methodology that would maximise the recovery of low concentration forensic samples.

Virtual anthropology? Reliability of three-dimensional photogrammetry as a forensic anthropology measurement and documentation technique.

Osseous remains provide forensic anthropologists with morphological and osteometric information that can be used in building a biological profile. By conducting a visual and physical examination, an anthropologist can infer information such as the sex and age of the deceased. Traditionally, morphological and osteometric information is gathered by physically handling remains for analysis.

The novel use of a spray-on rubber coating to recover cellular material from the surface of bricks.

Currently, forensic investigators utilise various types of swabs and tape lifts to recover cellular material from coarse surfaces identified during a criminal investigation. However, a number of challenges prevent successful recovery and therefore warrants the need for an alternative method. Plasti dip® is peel-off rubber coating that can be applied to most surfaces and may have an application in the recovery of DNA from coarse surfaces.

Working the crowd for forensic research: A review of contributor motivation and recruitment strategies used in crowdsourcing and crowdfunding for scientific research.

Crowdsourcing and crowdfunding have been successfully used in a range of scientific disciplines and present opportunities for forensic researchers to draw on the power of large numbers of people to contribute to research projects through participation or by providing an alternative source of funding. This review aimed to examine whether contributors to crowd science and crowdfunding for scientific research are motivated to participate or provide financial support by the same factors, and to examine recruitment strategies in an attempt to identify a potential crowd for forensic researchers to approach. There was found to be limited research into crowdfunding for scientific research that addressed the motivations of contributors or recruitment strategies used, and no conclusions could be made.

Examination of the temporal variation of peptide content in decomposition fluid under controlled conditions using pigs as human substitutes.

We report the preliminary observations of the peptide content of decomposition fluid produced under controlled laboratory conditions and in the absence of a soil matrix. Four domestic pig (Sus scrofa domesticus) cadavers were used to model human decomposition over a four-week trial period; physical characteristics were recorded and the peptide components of decomposition fluid was analysed using high performance liquid chromatography-time of flight mass spectrometry. Preliminary data analysis indicated that a range of peptides were consistently detected across the course of the trial period and 27 of these were common to all four cadavers; 22 originating from haemoglobin.

A pilot study: The effects of repeat washing and fabric type on the detection of seminal fluid and spermatozoa.

In sexual assault cases and more specifically those involving childhood sexual abuse (CSA), victims may have had their potentially semen-stained clothing washed multiple times before a criminal investigation commences. Although it has been previously demonstrated that spermatozoa persist on cotton clothing following a single wash cycle, items of clothing washed multiple times are not routinely examined in these cases because of the assumption that the laundering process would have removed all seminal fluid and spermatozoa. The aim of this study was to examine the persistence of seminal fluid and spermatozoa on a range of fabric types including cotton, nylon, terry towel (100% cotton), polyester fleece, satin and lace which were laundered up to six times.

Short-duration stimulation of the supplementary eye fields perturbs anti-saccade performance while potentiating contralateral head orienting.

Many forms of brain stimulation utilize the notion of state dependency, whereby greater influences are observed when a given area is more engaged at the time of stimulation. Here, by delivering intracortical microstimulation (ICMS) to the supplementary eye fields (SEF) of monkeys performing interleaved pro- and anti-saccades, we show a surprising diversity of state-dependent effects of ICMS-SEF. Short-duration ICMS-SEF passed around cue presentation selectively disrupted anti-saccades by increasing reaction times and error rates bilaterally, and also recruited neck muscles, favoring contralateral head turning to a greater degree on anti-saccade trials.

Recruitment of a contralateral head turning synergy by stimulation of monkey supplementary eye fields.

The supplementary eye fields (SEF) are thought to enable higher-level aspects of oculomotor control. The goal of the present experiment was to learn more about the SEF's role in orienting, specifically by examining neck muscle recruitment evoked by stimulation of the SEF. Neck muscle activity was recorded from multiple muscles in two monkeys during SEF stimulation (100 μA, 150-300 ms, 300 Hz, with the head restrained or unrestrained) delivered 200 ms into a gap period, before a visually guided saccade initiated from a central position (doing so avoids confounds between initial position and prestimulation neck muscle activity).

Neuromuscular recruitment related to stimulus presentation and task instruction during the anti-saccade task.

The contextual control of movement requires the transformation of sensory information into appropriate actions, guided by task-appropriate rules. Previous conceptualizations of the sensorimotor transformations underlying anti-saccades (look away from a stimulus) have suggested that stimulus location is first registered and subsequently transformed into its mirror location before being relayed to the motor periphery. Here, by recording neck muscle activity in monkeys performing anti-saccades, we demonstrate that stimulus presentation induces a transient recruitment of the neck muscle synergy used to turn the head in the wrong direction, even though subjects subsequently looked away from the stimulus correctly.

Properties of human eye-head gaze shifts in an anti-gaze shift task.

We investigated the metrics and kinematics of human eye-head gaze shifts using the anti-gaze shift task. Surprisingly, no systematic difference was found between peak gaze velocities of large pro- and anti-gaze shifts. In a follow-up experiment that equated perceived stimulus luminance across multiple eccentricities, pro-gaze shifts were consistently faster than anti-gaze shifts.

Neuromuscular consequences of reflexive covert orienting.

Visual stimulus presentation activates the oculomotor network without requiring a gaze shift. Here, we demonstrate that primate neck muscles are recruited during such reflexive covert orienting in a manner that parallels activity recorded from the superior colliculus (SC). Our results indicate the presence of a brainstem circuit whereby reflexive covert orienting is prevented from shifting gaze, but recruits neck muscles, predicting that similarities between SC and neck muscle activity should extend to other cognitive processes that are known to influence SC activity.