Mental health and social support among public safety personnel.

BACKGROUND: Social support may be a protective factor for the mental health of public safety personnel (PSP), who are frequently exposed to potentially psychologically traumatic events and report substantial post-traumatic stress disorder (PTSD) and major depressive disorder (MDD) symptoms. Research examining perceived social support and its association with PTSD and MDD in different PSP categories (e.g. firefighters, paramedics) is limited. AIMS: To examine differences in perceived social support across PSP and determine whether perceived social support is associated with differences in rates of MDD and PTSD. METHODS: We asked Canadian PSP, including correctional workers and officers, public safety communications officials, firefighters, paramedics, municipal and provincial police officers, and Royal Canadian Mounted Police (RCMP) officers, to complete an online anonymous survey that assessed socio-demographic information (e.g. occupation, sex, marital status, service years), social supports and symptoms of mental disorders, including PTSD and MDD. Analyses included ANOVA and logistic regression models. RESULTS: Perceived social support differed by PSP occupation. RCMP officers reported lower social support than all other PSP except paramedics. For most PSP categories, PSP who reported greater social support were less likely to screen positive for PTSD (adjusted odds ratios [AORs]: 0.90-0.93). Across all PSP categories, greater perceived social support was associated with a decreased likelihood of screening positive for MDD (AORs: 0.85-0.91). CONCLUSIONS: Perceived social support differs across some PSP categories and predicts PTSD and MDD diagnostic status. Studies involving diagnostic clinical interviews, longitudinal designs and social support interventions are needed to replicate and extend our results.

Mental disorders, suicidal ideation, plans and attempts among Canadian police.

BACKGROUND: Recent investigations have demonstrated a significant prevalence of mental health disorders, including post-traumatic stress disorder (PTSD), and suicidal ideation, plans and attempts among Canadian public safety personnel, including police officers. What remains unknown is the relationship between mental disorders and suicide among sworn police officers, and the prevalence of both among civilian police workers. AIMS: To examine the relationship between suicidal ideation, plans and attempts and positive mental health screens for depression, anxiety, panic disorder, alcohol abuse and PTSD among Canadian sworn and civilian police employees. METHODS: Participants completed an online survey that included self-report screening tools for depression, anxiety, panic disorder, alcohol abuse and PTSD. Respondents were also asked if they ever contemplated, planned or attempted suicide. Between-group (Royal Canadian Mounted Police [RCMP], provincial/municipal police and civilians) differences on mental health screening tools were calculated using Kruskal-Wallis analyses. The relationship between mental disorders and suicidal ideation, plans and attempts was evaluated with a series of logistic regressions. RESULTS: There were 4236 civilian and sworn officer participants in the study. RCMP officers reported more suicidal ideation than other police and scored highest on measures of PTSD, depression, anxiety, stress and panic disorder, which were significantly associated with suicidal ideation and plans but not attempts. Relative to provincial and municipal police, civilians reported more suicide attempts and scored higher on measures of anxiety. CONCLUSIONS: The results identify a strong relationship between mental health disorders and increased risk for suicidal ideation, plans and attempts among sworn and civilian Canadian police employees.

The Impact of Acute Stress Physiology on Skilled Motor Performance: Implications for Policing.

Investigations of police performance during acutely stressful situations have primarily focused on higher-order cognitive processes like attention, affect or emotion and decision-making, and the behavioral outcomes of these processes, such as errors in lethal force. However, behavioral outcomes in policing must be understood as a combination of both higher-order processes and the physical execution of motor skills. What is missing from extant police literature is an understanding of how physiological responses to acute stress contribute to observed decrements in skilled motor performance at the neuromuscular level. The purpose of the current paper is to fill this knowledge gap in the following ways: (1) review scientific evidence for the physiological (i.e., autonomic, endocrine, and musculoskeletal) responses to acutely stressful exposures and their influence on skilled motor performance in both human and animal models, (2) review applied evidence on occupationally relevant stress physiology and observed motor decrements in performance among police, and (3) discuss the implications of stress physiology for police training and identify future directions for applied researchers. Evidence is compelling that skill decay is inevitable under high levels of acute stress; however, robust evidence-informed training practices can help mitigate this decay and contribute to officer safety.

The development of Protophormia terraenovae (Robineau-Desvoidy) at constant temperatures and its minimum temperature threshold.

The immature development of the forensically important blow fly Protophormia terraenovae (Robineau-Desvoidy) (Diptera: Calliphoridae) was observed at a range of constant temperatures: 9.8, 11, 13, 15, 20, 25, 28, 30, and 32°C, and the minimum developmental times and mode of development to reach each stage were recorded. A comparison of the actual minimum temperature threshold was made to findings from linear extrapolation. The minimum temperature thresholds for the 1st, 2nd and 3rd instars fell within 9.8 and 11°C and those of the post feeding, pupal and adult stages fell within the range of 11-13°C. However, in all cases the actual minimum temperature thresholds were greatly underestimated by the linear method.

Decomposition of carrion in the marine environment in British Columbia, Canada.

Decomposition of carrion in the marine environment is not well understood. This research involved the decomposition of pig carcasses in Howe Sound in British Columbia. Freshly killed pigs were submerged at two depths, 7.6 m and 15.2 m. The carcasses were tethered so that they could float or sink, but not drift away. Observations were made from May until October. Decomposition was more greatly influenced by sediment type of the sea floor and whether the carcass remained floating, than by depth. Decomposition stages were modified in the marine environment from that seen on land, or in freshwater and were similar to those reported in human death investigations in the marine environment.

Determining time of death using blow fly eggs in the early postmortem interval.

A forensic entomology case is presented which is interesting for two reasons; firstly, it uses egg development, but secondly, it involves a case which is over 20 years old, and was recently re-opened. The only entomological evidence was in the form of photographs. Usually, it is not possible to make any determinations from photographs alone, as species and age cannot be determined. However, this case was particularly unusual, as close up photographs taken by police at the crime scene showed the first egg eclosion. Weather records, developmental data and degree day accumulations, together with a knowledge of local species and their habitats, allowed determination of the time since death. Time of death was affirmed when the defendant was convicted of first degree murder more than 20 years after the killing.

Simple method for developing percentile growth curves for height and weight.

The present paper demonstrates the ease of use of method I by Preece and Baine ([1978] Ann Hum Biol 5:1-24) in generating smoothed growth curves for both height and weight. Using the National Center for Health Statistics (NCHS) growth curve data, smoothed curves were developed and compared to those produced using the least-squares-cubic-spline method. Based on the lower sum of squares and better fit of shape as indicated by residual examination, it was concluded that the method I curve fitting procedure by Preece and Baine ([1978] Ann Hum Biol 5:1-24) fit centile growth curves for height and weight in 2-18-year-old male and female children as well as, if not better than, the least-squares-cubic-spline method used in developing the 1979 NCHS growth curves. Further, as this paper demonstrates, smoothed curves can be generated on a desktop computer using readily available software (the SOLVER function within Microsoft EXCEL).

Postirradiation hyperthermia selectively potentiates the merocyanine 540-sensitized photoinactivation of small cell lung cancer cells.

Lung cancer has long been considered a disease that might benefit from the dose escalation of radio/chemotherapy afforded by a stem cell transplant. However, the clinical experience with high-dose chemotherapy and autologous bone marrow transplantation in lung cancer has been disappointing, with most trials showing little or no improvement in long-term survival. Unfortunately, lung cancer has a tendency to metastasize to the bone marrow, and lung cancer cells are known to circulate in the peripheral blood. Therefore, there is concern that autologous stem cell grafts from lung cancer patients may reinoculate recipients with live tumor cells. Photochemical purging of stem cell grafts with Merocyanine 540 (MC540) is highly effective against a wide range of leukemia and lymphoma cells and is well tolerated by normal hematopoietic stem and progenitor cells. Most solid tumor cells (including lung cancer cells), however, are only moderately sensitive or refractory to MC540-mediated photodynamic therapy (PDT). We report here that postirradiation hyperthermia (< or = 42 degrees C, 3 h) potentiates the MC540-mediated photoinactivation of both wild-type (H69) and cisplatin-resistant mutant (H69/CDDP) small cell lung cancer cells by several orders of magnitude, while only minimally enhancing the depletion of normal human granulocyte/macrophage progenitor cells. Our data suggest that postirradiation hyperthermia provides a simple and effective means of extending the utility of MC540-PDT to the purging of stem cell grafts contaminated with lung cancer and possibly other solid tumor cells.

Minimum and maximum development rates of some forensically important Calliphoridae (Diptera).

Blow fly development rates are frequently used to estimate elapsed time since death in homicide investigations in the first few weeks after death. However, in order to make more precise estimates of time since death, accurate developmental data must be generated for all carrion species, and at temperatures that are comparable with those found at crime scenes. This paper presents developmental rates determined for five forensically important species in British Columbia, Phormia regina (Meigen), Phaenicia sericata (Meigen), Eucalliphora latifrons (Hough), Lucilia illustris (Meigen), and Calliphora vicina Robineau-Desvoidy, at several temperatures.

Effect of molecular structure on the performance of triarylmethane dyes as therapeutic agents for photochemical purging of autologous bone marrow grafts from residual tumor cells.

Extensively conjugated cationic molecules with appropriate structural features naturally accumulate into the mitochondria of living cells, a phenomenon typically more prominent in tumor than in normal cells. Because a variety of tumor cells also retain pertinent cationic structures for longer periods of time compared with normal cells, mitochondrial targeting has been proposed as a selective therapeutic strategy of relevance for both chemotherapy and photochemotherapy of neoplastic diseases. Here we report that the triarylmethane dye crystal violet stains cell mitochondria with efficiency and selectivity, and is a promising candidate for photochemotherapy applications. Crystal violet exhibits pronounced phototoxicity toward L1210 leukemia cells but comparatively small toxic effects toward normal hematopoietic cells (murine granulocyte-macrophage progenitors, CFU-GM). On the basis of a comparative examination of chemical, photochemical, and phototoxic properties of crystal violet and other triarylmethane dyes, we have identified interdependencies between molecular structure, and selective phototoxicity toward tumor cells. These structure-activity relationships represent useful guidelines for the development of novel purging protocols to promote selective elimination of residual tumor cells from autologous bone marrow grafts with minimum toxicity to normal hematopoietic stem cells.

Human bites and the risk of human immunodeficiency virus transmission.

The risk of human immunodeficiency virus (HIV) transmission following a bite injury is important to many groups of people. The first are those who are likely to be bitten as an occupational risk, such as police officers and institutional staff. Another group are represented by the victims and perpetrators of crimes involving biting, both in attack and defense situations. The possibility of these bites transmitting a potentially fatal disease is of interest to the physicians who treat such patients and the legal system which may have to deal with the repercussions of such a transmission. Bite injuries represent 1% of all emergency department admissions in the United States, and human bites are the third most common following those of dogs and cats. The worldwide epidemic of HIV and acquired immunodeficiency syndrome (AIDS) continues, with >5 million new cases last year and affecting 1 in 100 sexually active adults. A review of the literature concerning human bites, HIV and AIDS, HIV in saliva, and case examples was performed to examine the current opinion regarding the transmission of HIV via this route. A bite from an HIV-seropositive individual that breaks the skin or is associated with a previous injury carries a risk of infection for the bitten individual.

Wildlife forensic entomology: determining time of death in two illegally killed black bear cubs.

Forensic entomology is now commonly used to determine time of death in human death investigations. However, it can be equally applicable to wildlife crimes. This paper describes the use of entomology to determine time of death in the illegal killing of two young bear cubs in Manitoba, Canada. Two cubs were found shot, disemboweled, with their gall bladders removed. Natural Resource officers (Conservation Officers) and a Royal Canadian Mounted Police (R.C.M.P.) officer examined the remains, and the R.C.M.P. officer collected insect evidence. The only insects on the remains were adult blow flies coming to lay eggs and the blow fly eggs themselves (Diptera: Calliphoridae). The time of hatch was recorded and the insects were reared to adulthood. Time of hatch, together with species identification, macro and micro climate and lab developmental data were used to determine the time of death. The time was consistent with the time that the defendants were seen at the scene and was used in their conviction. This case illustrates that insect evidence can be equally as valuable in poaching cases as in homicide cases. However, in most cases Conservation Officers are unaware of this science. It is therefore, extremely important for more Conservation Officers to be educated about this field.

Insect succession on buried carrion in two biogeoclimatic zones of British Columbia.

We established a database of insect succession on buried carrion in two biogeoclimatic zones of British Columbia over a 16-month period beginning June 1995. Pig (Sus scrofa L.) carcasses were buried shortly after death in the Coastal Western Hemlock and Sub-boreal Spruce biogeoclimatic zones of British Columbia. Buried pigs exhibited a distinct pattern of succession from that which occurred on above-ground carrion. The species composition and time of colonization for particular species differed between the two zones. Therefore ideally, a database of insect succession on buried carrion should be established for each major biogeoclimatic zone. We did not observe maggot masses on any of the buried carcasses; therefore, the presence of maggot masses may indicate a delayed burial. Soil temperature was a better indicator of internal buried carcass temperature (r2 = 0.92, p < 0.0001) than was ambient air temperature (r2 = 0.60, p < 0.0001); thus soil temperature should be used to determine developmental rates of insects for determination of the postmortem interval by a forensic entomologist.

Human morphology and temperature regulation.

For nearly a century individuals have believed that there is a link between human morphology and one's thermoregulatory response in adverse environments. Most early research was focussed on the rate of core cooling in a male adult population and the role of subcutaneous adipose tissue, surface area and the surface-area-to-mass ratio in one's ability to withstand varying degrees of cold stress. More recently research has addressed heat tolerance in various populations, exploring the role of subcutaneous adipose tissue, surface area and the surface-area-to-mass ratio in one's ability to maintain thermal equilibrium in warm and hot, dry and humid environments. Since the late 1970s an emphasis has been placed on the role of muscle and muscle perfusion in total-body thermal insulation. Yet, despite the history of research pertaining to human morphology and temperature regulation there is little consensus as to the impact of variations in human morphology on thermoregulatory responses. Individuals differing in body size, shape and composition appear to respond quantitatively differently to variations in both ambient and core temperatures but the interrelations between morphological components and temperature regulation are complex. It is the purpose of this paper to examine the literature pertaining to the impact of variations in muscularity, adipose tissue thickness and patterning, surface area and the surface-area-to-mass ratio on thermoregulation and thermal stability in response to both heat and cold stress.

Modeling dynamic skinfold compression.

Real time compression of skinfolds was measured at three sites (triceps, abdominal medial calf), using a Slim Guide skinfold caliper adapted by the addition of a potentiometer, on eight males and eight females (age range 18-40 years). An average of eight trials for each subject at each site was used in modeling the compression curves. A mechanical model was developed, comprised of two parallel spring and viscous components in series with each other. $ Tt = Tinitial + F \left( { 1 \over k_1 } - \left\lceil { e { -k_1 t \over b_1 } \over k_1 } \right\rceil \right) + F \left( { 1 \over k_2 } - \left\lceil { e { -k_2 t \over b_2 } \over k_2 } \right\rceil \right) $ where: Tt = thickness at time t; Tinitial = intial skinfold thickness; F = force exerted by caliper; k(1) and k(2) = coefficients of elasticity; b(1) and b(2) = coefficients of viscosity. This two-component model was the best fitting model in comparison to one or three component alternatives. The coefficients of the model were different by sex and skinfold site. Coefficients for females showed greater elasticity and less viscosity compared to those for males. Further, there appeared to be a systematic site difference with the triceps having less elasticity and viscosity in both sexes. Am. J. Hum. Biol. 11:531-537, 1999. Copyright 1999 Wiley-Liss, Inc.

Resilience of anthropometric data assembly strategies to imposed error.

The aim of this study was to examine strategies for selecting a criterion value during anthropometric data assembly and their resilience to imposed error. Sixty-seven women aged 16-60 years were subjected to three separate series of measurements, which included six skinfolds and three girths. A random error term was added to the first of the three series of measurements to produce a pseudo-series containing error, termed the 'erroneous replicated series'. Five strategies were then used to determine the criterion value of each of the replication series: the first measurement, the mean of the first two measurements, the mean of all three measurements, the mean of the closest two measurements and the median of the three measurements. The technical error between the criterion values of the true and the flawed replication series for each of the selection strategies was calculated. We found that, for five of the skinfolds and all of the girths, the median value provided the smallest technical error of measurement between the criterion values for the true and erroneous replication series. We conclude that the strategy of selecting the median of three measurements is the most resilient to imposed error.

The use of insects to determine time of decapitation: a case-study from British Columbia.

A case is presented in which insects were used to determine time of decapitation. A severed human head was located on 28 June in a ditch on Vancouver Island, British Columbia, Canada. The victim had been missing since 17 June. Prepupal Calliphora vomitoria (L.) were found at the cut surface of the neck and no evidence of insect feeding was observed at any of the natural orifices; the eyes were intact. Meteorological and insect developmental data indicated that the insects had been oviposited on or before 20 June. The lack of feeding at the orifices, together with the evidence of feeding and presence of insects at the cut surface of the neck indicated that the eggs had been laid after decapitation. Therefore, decapitation had occurred on or before 20 June. This was consistent with later police evidence.

Inactivation of photosensitizing merocyanine dyes by plasma, serum and serum components.

Merocyanine dyes with an oxygen in the electron donor heterocycle were rapidly degraded by plasma, serum and serum components. Replacement of the oxygen by a sulfur or selenium atom rendered the dyes refractory to degradation. The degradation of labile merocyanine dyes was temperature dependent and oxygen independent. The plasma component that was responsible for the degradation of merocyanine dyes was sensitive to heat and detergent, suggesting an enzymatic process. The identification of the structural requirements for sensitivity/resistance to degradation provides the experimenter with a simple means to manipulate the stability of merocyanines in high serum or plasma environments and may expand the clinical utility of merocyanine photosensitizers beyond their traditional role in the extracorporeal purging of bone marrow grafts.

Immunotherapy trial for horses in British Columbia with Culicoides (Diptera:Ceratopogonidae) hypersensitivity.

Immunotherapy was used to treat horses in British Columbia for Culicoides hypersensitivity. This is a severe, chronic, recurrent allergic disease of horses that results in severe irritation, large lesions, hair loss and secondary infection in the ventral midline, mane, and proximal region of the tail. A crude Culicoides extract was injected subcutaneously, in increasing doses, into 10 horses that were affected severely by the disease. Weekly doses reduced the clinical signs in 9 of the 10 horses in the 1st yr. Eight horses were treated with a maintenance dose during a 2nd yr. After the 2nd yr, 3 horses were completely free of clinical signs, 3 showed much less severe clinical signs than in untreated years, and 2 showed moderate reduction in clinical signs. Dosage, frequency of injections, and possible future applications of this technique are discussed.

Rehabilitation learning needs: patient and family perceptions.

Understanding consumer needs for information provides the foundation for empowering patients and families to assume more responsibility for their own care both in hospital and after discharge. Self administered questionnaires identified adult rehabilitation learning needs from the perspectives of patients and their families both during and following hospitalization. The greatest needs for both groups in both time periods were for information about medical, psychosocial and community integration topics. During the in-patient phase, families identified high needs for information which suggests that they should be targeted for educational activities along with patients. Surveys repeated 6 weeks following discharge indicated that information needs were lower but continued to exist.