Occupational injuries in Canadian youth: an analysis of 22 years of surveillance data collected from the Canadian Hospitals Injury Reporting and Prevention Program.

INTRODUCTION: Inexperience, inadequate training and differential hazard exposure may contribute to a higher risk of injury in young workers. This study describes features of work-related injuries in young Canadians to identify areas for potential occupational injury prevention strategies. METHODS: We analyzed records for youth aged 10-17 presenting to Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP) emergency departments (EDs) from 1991-2012. We classified work-related injuries into job groups corresponding to National Occupational Classification for Statistics 2006 codes and conducted descriptive analyses to assess injury profiles by job group. Age- and sex-adjusted proportionate injury ratios (PIRs) and 95% confidence intervals (CIs) were calculated to compare the nature of injuries between occupational and non-occupational events overall and by job group. RESULTS: Of the 6046 injuries (0.72% of events in this age group) that occurred during work, 63.9% were among males. Youth in food and beverage occupations (54.6% males) made up 35.4% of work-related ED visits and 10.2% of work-related hospital admissions, while primary industry workers (76.4% males) made up 4.8% of work-related ED visits and 24.6% of work-related hospital admissions. PIRs were significantly elevated for burns (9.77, 95% CI: 8.94-10.67), crushing/amputations (6.72, 95% CI: 5.79-7.80), electrical injuries (6.04, 95% CI: 3.64-10.00), bites (5.09, 95% CI: 4.47-5.79), open wounds (2.68, 95% CI: 2.59-2.78) and eye injuries (2.50, 95% CI: 2.20-2.83) in occupational versus non-occupational events. These were largely driven by high proportional incidence of injury types unique to job groups. CONCLUSION: Our findings provide occupation group-specific information on common injury types that can be used to support targeted approaches to reduce incidence of youth injury in the workplace.

TITRE: Accidents de travail impliquant des jeunes Canadiens : analyse de 22 années de surveillance des données recueillies à partir du Système canadien hospitalier d'information et de recherche en prévention des traumatismes. INTRODUCTION: L'inexpérience, une formation inadéquate et une exposition accrue au danger sont susceptibles de contribuer à un risque plus élevé d'accidents chez les jeunes travailleurs. Cette étude décrit les caractéristiques des accidents de travail impliquant de jeunes Canadiens afin d'identifier les secteurs pour lesquels élaborer des stratégies de prévention en matière d'accidents de travail. MÉTHODOLOGIE: Nous avons analysé le dossier des jeunes de 10 à 17 ans qui se sont présentés à un service des urgences (SU) faisant partie du Système canadien hospitalier d'information et de recherche en prévention des traumatismes (SCHIRPT) entre 1991 et 2012. Nous avons classé les accidents de travail en fonction de groupes d'emploi correspondant à la Classification nationale des professions (codes statistiques 2006) et nous avons effectué des analyses descriptives afin d'établir le profil des accidents en fonction de ces groupes d'emploi. Nous avons calculé des rapports proportionnels de blessures (RPB) en fonction de l'âge et du sexe ainsi que des intervalles de confiance à 95 % pour comparer la nature des blessures survenues en contexte professionnel et en contexte non professionnel, à la fois dans l'ensemble et par groupe d'emploi. RÉSULTATS: Parmi les 6 046 blessures ayant eu lieu au travail (0,72 % des cas dans ce groupe d'âge), 63,9 % touchaient des garçons. Les jeunes (54,6 % de garçons) œuvrant dans l'industrie des aliments et des boissons ont formé 35,4 % des consultations aux SU en lien avec le travail et 10,2 % des admissions liées au travail, alors que les travailleurs du secteur primaire (76,4 % de garçons) représentaient 4,8 % des consultations aux SU liées au travail et 24,6 % des admissions liées au travail. Les RPB ont été significativement élevés pour les brûlures (9,77, IC à 95 % : 8,94 à 10,67), les blessures par écrasement et les amputations (6,72, IC à 95 % : 5,79 à 7,80), les blessures causées par l'électricité (6,04, IC à 95 % : 3,64 à 10,00), les morsures (5,09, IC à 95 % : 4,47 à 5,79), les plaies ouvertes (2,68, IC à 95 % : 2,59 à 2,78) et les lésions oculaires (2,50, IC à 95 % : 2,20 à 2,83) dans un contexte professionnel par rapport aux cas en contexte non professionnel. Ceci s'explique en bonne partie par l'incidence proportionnelle élevée de certains types de blessures spécifiques à des groupes d'emploi. CONCLUSION: Nos conclusions fournissent des renseignements relatifs à certains groupes professionnels sur des types de blessures courantes susceptibles de favoriser l'adoption d'approches ciblées à l'égard de la réduction de l'incidence des blessures chez les jeunes en milieu de travail.

Slow delivery of a nitrification inhibitor (dicyandiamide) to soil using a biodegradable hydrogel of chitosan.

Using chemical inhibitors to reduce soil nitrification decreases emissions of environmental damaging nitrate and nitrous oxide and improves nitrogen use efficiency in agricultural systems. The efficacy of nitrification inhibitors such as dicyandiamide (DCD) is limited in soil due to biodegradation. This study investigated if the persistence of DCD could be sustained in soil by slow release from a chitosan hydrogel. DCD was encapsulated in glyoxal-crosslinked chitosan beads where excess glyoxal was (i) partly removed (C beads) or (ii) allowed to dry (CG beads). The beads were tested in water and in soil. The beads contained two fractions of DCD: one which was quickly released in water, and one which was not. A large DCD fraction within C beads was readily available: 84% of total DCD bead content was released after 9h immersion in water, while between 74% and 98% was released after 7d in soil under low to high moisture conditions. A lower percentage of encapsulated DCD was readily released from CG beads: 19% after 9h in water, and 33% after 7d in soil under high rainfall conditions. Kinetic analysis indicated that the release in water occurred by quasi-Fickian diffusion. The results also suggest that DCD release was controlled by bead erosion and the leaching of glyoxal derivatives, predominantly a glyoxal-DCD adduct whose release was positively correlated with that of DCD (R(2)=0.99, p⩽0.0001). Therefore, novel chitosan/glyoxal composite beads show a promising slow-release potential in soil for agrochemicals like DCD.

Age related differences in work injuries and permanent impairment: a comparison of workers' compensation claims among adolescents, young adults, and adults.

BACKGROUND: There is growing evidence that adolescent workers are at greater risk for work injury. AIMS: To investigate the severity of work injuries across age groups. METHODS: Workers' compensation records were used to examine work related injuries among adolescents (15-19 years old), young adults (20-24 years old), and adults (25+ years old) between 1993 and 2000. The incidence of compensated injuries was calculated for each age group and compared by gender, industry, and type of injury. The presence and degree of permanent impairment in each age group was also examined. RESULTS: For males, adolescents and young adults had higher claim rates than adults. For females, adults had the highest claim rates and young adults the lowest. Rates of permanent impairment indicated that age was positively associated with severity of injury. CONCLUSIONS: Indicators of health consequences, in particular presence of permanent impairment, provide preliminary evidence that compensated work injuries sustained by youth are not as serious as injuries sustained by adults. Nevertheless, there was evidence that some young workers sustain injuries that have long term consequences. Documenting the consequences of the injuries that young workers sustain has implications for secondary prevention efforts and health services policy.

Role of the bandage soft contact lens in the postoperative laser in situ keratomileusis patient.

PURPOSE: To determine whether a bandage soft contact lens (BSCL) is routinely needed in the postoperative laser in situ keratomileusis (LASIK) patient and whether topical tetracaine 0.5% or diclofenac sodium 0.1% (Voltaren) is more effective in relieving patient discomfort than a BSCL. SETTING: LCA-Vision Center, Toronto, Ontario, Canada. METHODS: In this prospective randomized comparative study, all patients had bilateral simultaneous LASIK procedures. Post-LASIK patient comfort was evaluated through 3 arms of the study: BSCL versus no BSCL, 40 consecutive patients with 1 eye randomized to receive a BSCL and no BSCL in the fellow eye; BSCL versus tetracaine 0.5%, 26 consecutive patients with 1 eye randomized to receive a BSCL and tetracaine 0.5% in the fellow eye; tetracaine 0.5% versus Voltaren, 54 consecutive patients with 1 eye randomized to receive tetracaine 0.5% and Voltaren in the fellow eye. RESULTS: The patient preferences after LASIK were as follows: BSCL versus no BSCL-12 (30%) versus 23 (58%) (P =.062); BSCL versus tetracaine 0.5%-4 (15%) versus 22 (85%) (P <.001). On average, the eyes with no BSCL had a 2-line improvement in uncorrected visual acuity over the BSCL eyes. Tetracaine 0.5% versus Voltaren-13 (24%) versus 21 (39%) (P =.170). CONCLUSIONS: The routine use of a BSCL in the postoperative LASIK patient is not necessary. Voltaren and tetracaine 0.5% were safe and more effective in relieving postoperative patient discomfort and resulted in improved visual acuity immediately postoperatively.

Neuromorphic hardware databases for exploring structure-function relationships in the brain.

Neuromorphic hardware is the term used to describe full custom-designed integrated circuits, or silicon 'chips', that are the product of neuromorphic engineering--a methodology for the synthesis of biologically inspired elements and systems, such as individual neurons, retinae, cochleas, oculomotor systems and central pattern generators. We focus on the implementation of neurons and networks of neurons, designed to illuminate structure-function relationships. Neuromorphic hardware can be constructed with either digital or analogue circuitry or with mixed-signal circuitry--a hybrid of the two. Currently, most examples of this type of hardware are constructed using analogue circuits, in complementary metal-oxide-semiconductor technology. The correspondence between these circuits and neurons, or networks of neurons, can exist at a number of levels. At the lowest level, this correspondence is between membrane ion channels and field-effect transistors. At higher levels, the correspondence is between whole conductances and firing behaviour, and filters and amplifiers, devices found in conventional integrated circuit design. Similarly, neuromorphic engineers can choose to design Hodgkin-Huxley model neurons, or reduced models, such as integrate-and-fire neurons. In addition to the choice of level, there is also choice within the design technique itself; for example, resistive and capacitive properties of the neuronal membrane can be constructed with extrinsic devices, or using the intrinsic properties of the materials from which the transistors themselves are composed. So, silicon neurons can be built, with dendritic, somatic and axonal structures, and endowed with ionic, synaptic and morphological properties. Examples of the structure-function relationships already explored using neuromorphic hardware include correlation detection and direction selectivity. Establishing a database for this hardware is valuable for two reasons: first, independently of neuroscientific motivations, the field of neuromorphic engineering would benefit greatly from a resource in which circuit designs could be stored in a form appropriate for reuse and re-fabrication. Analogue designers would benefit particularly from such a database, as there are no equivalents to the algorithmic design methods available to designers of digital circuits. Second, and more importantly for the purpose of this theme issue, is the possibility of a database of silicon neuron designs replicating specific neuronal types and morphologies. In the future, it may be possible to use an automated process to translate morphometric data directly into circuit design compatible formats. The question that needs to be addressed is: what could a neuromorphic hardware database contribute to the wider neuroscientific community that a conventional database could not? One answer is that neuromorphic hardware is expected to provide analogue sensory-motor systems for interfacing the computational power of symbolic, digital systems with the external, analogue environment. It is also expected to contribute to ongoing work in neural-silicon interfaces and prosthetics. Finally, there is a possibility that the use of evolving circuits, using reconfigurable hardware and genetic algorithms, will create an explosion in the number of designs available to the neuroscience community. All this creates the need for a database to be established, and it would be advantageous to set about this while the field is relatively young. This paper outlines a framework for the construction of a neuromorphic hardware database, for use in the biological exploration of structure-function relationships.

Electrochemical studies on the stability and corrosion resistance of titanium-based implant materials.

The corrosion susceptibility of Ti, Ti-6A1-4V and Ti-45Ni was studied in a buffered saline solution using anodic polarisation and electrochemical impedance measurements. Pitting potentials as low as + 250 mV(SCE) were recorded for Ti-45Ni and once initiated pits continued to propagate at potentials as low as -150 mV(SCE). It was possible to increase the pitting potential of Ti-45Ni to values greater than +800 mV(SCE) using a H2O2 surface treatment procedure; however, this surface modification process had no beneficial effect on the rate of pit repassivation. Impedance spectra, recorded under open-circuit conditions, were modelled using a dual oxide film model; a porous outer layer and an inner barrier oxide layer. The nature of this porous outer layer was found to depend on the nature of the electrode material and the presence of phosphate anions in the saline-buffered solution. The porous layers formed on Ti-45Ni and Ti-6Al-4V in the presence of phosphate anions had low resistances typically between 10 and 70 ohm cm2. Much higher porous layer resistances were recorded for Ti and also for Ti-45Ni and Ti-6Al-4V in the absence of the phosphate anions.

Assisted living must radically restructure service delivery in order to financially survive.

Increased acuity levels, rising costs, competition and demands upon occupancy levels will all have a dramatic impact upon the financial viability of assisted living facilities (ALFs) in Connecticut and New England.

Silicon cellular morphology.

We describe a design technique for neuromorphic engineering that exploits both Mead's notion of physical equivalence between transistors and ion channels and the intrinsic properties of the materials of which transistors are composed. This is in contrast to the "algorithmic" design technique in common use. A "physical" design technique allows us to emphasise the morphology of cells. We hope to use this in an exploration of the effect of cell morphology upon function.

Aftercare telephone contacts with problem drinkers can serve a clinical and research function.

Research staff typically gather treatment outcome data, whereas clinicians perform aftercare contacts. To date no alcohol treatment outcome study has examined the utility of therapists collecting outcome data through aftercare contacts. Using the Alcohol Timeline Followback (TLFB) method modified for clinical aftercare contacts, 154 problem drinkers who were part of a cognitive-behavioral intervention completed the modified TLFB with their primary therapist during aftercare telephone contacts conducted 1 and 3 months after their last treatment session. Clients reported their daily alcohol use over the past 30 days using four consumption categories (i.e. 0 drinks, 1-4 drinks, 5-9 drinks and 10+ drinks). At a 6-month follow-up research interview, a trained research assistant gathered standard TLFB data from the clients that included the time period for aftercare contacts. Correlations between the two TLFB formats showed good alternate form reliability, especially for frequency of alcohol use. Discrepancies between reports were positively associated with heavier pre-treatment and post-treatment drinking, suggesting possible memory biases among heavier drinkers. Subject reports also closely paralleled collateral reports of the subjects' drinking. These results support the utility of a brief TLFB instrument for use by therapists in assessing clients' outcomes by telephone during aftercare contacts.

Corneal subepithelial infiltrates following excimer laser photorefractive keratectomy.

Corneal subepithelial opacification associated with pain, photophobia, and injection has been reported in the first to third day following photorefractive keratectomy (PRK). Regardless of treatment, the resolution has generally left the patient with permanent corneal scarring and a one to two line reduction in visual acuity. We surveyed 50 PRK surgeons and received responses from 17 on 30 cases of this complication, which occurs in approximately one in 300 cases. The etiology is unknown. Cases were first reported when nonsteroidal anti-inflammatory drugs, with or without occlusive contact lens, were substituted for conventional bandage occlusion in the postoperative protocol for PRK.

Alcohol and anxiety reduction in female social drinkers.

The present study used a 3 X 2 factorial design to investigate effects on assertive behavior and social anxiety of different doses of alcohol and individual differences in female social drinkers. Contrary to previous findings with men, a dose-dependent effect of alcohol was not found during the social interaction task. The high dose had mixed effects, reducing anxiety on some but not other dependent measures. The moderate dose resulted in significantly less assertiveness and increased heart rate during the social interaction, in high-tolerant subjects. Expectancies about intoxication failed to show significant effects. Of the individual difference variables, only acute tolerance significantly influenced alcohol's effects on anxiety. Alcohol did not reduce self-awareness.

Retrobulbar anesthesia for cataract surgery: comparison of bupivacaine and bupivacaine/lidocaine combinations.

Three groups of 15 patients each were randomly assigned to receive a retrobulbar anesthetic block with 0.5% bupivacaine, 0.5% bupivacaine/2% lidocaine or 0.5% bupivacaine/2% lidocaine/1:100 000 epinephrine for unilateral cataract surgery. Hyaluronidase was added to each of the preparations, which were used in double-blind fashion. Lid and globe akinesia and corneal anesthesia were graded after 4 minutes of ocular massage and 36 minutes later (at the end of the procedure) to assess the rapidity of onset and the duration of action of the anesthetics. Overall, bupivacaine/lidocaine/epinephrine was the most effective in producing akinesia of the lids and globe. Bupivacaine alone was more effective than bupivacaine/lidocaine without epinephrine in producing akinesia, although it was slower in producing anesthesia. There was no difference between the groups in the frequency of pain or of the need for analgesia 6 hours postoperatively.

Treatment of herpes simplex keratitis: comparison of acyclovir and vidarabine.

At three university centres 66 patients presenting with herpetic dendritic or geographic ulcers participated in a double-blind comparative study of 3% acyclovir and 3% vidarabine ointment. There was healing in 31 (97%) of the 32 patients treated with acyclovir, in a mean time of 6.3 days, and in 30 (88%) of the 34 treated with vidarabine, in a mean time of 7.1 days. The two medications were statistically equally effective, no difference being demonstrated in the healing rate, in the frequency of punctate epithelial keratitis or stromal keratitis, or in the final visual acuity.

Effect of retrobulbar anesthesia on ocular tension.

To determine the effect of retrobulbar lidocaine, with or without epinephrine, on intraocular pressure, 50 patients admitted to hospital for cataract surgery were selected at random. By applanation tonometry the tension of each eye was measured when the patient was placed on the operating table and 4 minutes after the retrobulbar injection. The decrease in intraocular pressure 4 minutes after the injection was not significant, clinically or statistically, and probably resulted from relaxation of the extraocular muscles.

The effect of pH and osmolarity on the ability of tolerate artificial tears.

Many patients with keratitis sicca complain that the commercially available artificial tears burn when they are instilled and fail to relieve their distressing symptoms. We examined the effects of altering both the pH and osmolarity of hydroxypropyl methylcellulose tear substitute on the tolerance of 15 patients with varying degrees of keratitis sicca. Approximately equal numbers of patients selected the neutral hypotonic tear preparations and the isotonic or near-isotonic alkaline tear substitutes. The isotonic alkaline tear preparation was preferred by the majority of our patients with moderate or severe dry eyes. A commercially available alkaline tear substitute is needed.

Herpes simplex keratitis in renal transplant recipients.

Herpes simplex epithelial keratitis developed in four renal transplant recipients while they were receiving high-dose systemic corticosteroid and immunosuppressive therapy. In all cases the presentation was atypical, and in two cases the course was protracted, leading to some visual loss from corneal scarring and opacification. With the immunocompromised patient it is important to seek early ophthalmologic consultation when even minor ocular symptoms develop.

Toleration of artificial tears - the effect of pH.

We studied the effect of altering the pH of an artificial tear preparation on the tolerance of 20 patients with keratoconjunctivitis sicca. Of those who expressed a preference, 11/17 preferred a tear substitute more alkaline than any preparation now available in North America. We recommend an alkaline tear substitute as a valuable alternative in patients with keratoconjunctivitis sicca.

Slow-release artificial tears and the treatment of keratitis sicca.

The slow-release artificial tear (SRAT) is a biodegradable, cellulosic polymer without preservative which is inserted beneath the tarsus of the lower lid, and which provides continuous lubrication and tear film stability to the eye. The SR-AT has been shown to reduce both subjective symptoms and objective signs in patients with keratitis sicca, and is a valuable adjunct to therapy in patients with this disease.

Surgical management of necrotizing scleritis.

We successfully used autogenous periosteum to reinforce the weakened sclera of two patients with necrotizing scleritis. One of these patients previously had an onlay scleral graft made from homologous banked sclera, which had subsequently melted. Autogenous periosteum is suggested as an alternative to banked sclera for scleral reinforcement.