Isabelle Tremblay

Impact of a meaning-centered intervention on job satisfaction and on quality of life among palliative care nurses

Objective: Palliative care (PC) nurses experience several recurrent organizational, professional, and individual challenges. To address existential and emotional demands, the meaning‐centered intervention was recently developed. The intervention applied didactic and process‐oriented strategies, including guided reflections, experiential exercises, and education based on themes of Viktor Frankls logotherapy. The objective of this study was to test its efficiency to improve job satisfaction and quality of life in PC nurses from three regional districts in Quebec Province, Canada.

Efficacy of a cognitive training programme for mild cognitive impairment: Results of a randomised controlled study

This study aimed to determine the efficacy of cognitive training in a 10-week randomised controlled study involving 22 individuals presenting with mild cognitive impairment of the amnestic type (MCI-A). Participants in the experimental group (n = 11) learned face–name associations using a paradigm combining errorless (EL) learning and spaced retrieval (SR) whereas participants in the control group (n = 11) were trained using an errorful (EF) learning paradigm. Psycho-educational sessions on memory were also provided to all participants. After neuropsychological screening and baseline evaluations, the cognitive training took place in 6 sessions over a 3-week period. The post-training and follow-up evaluations, at one and four weeks respectively, were performed by research assistants blind to the participants study group. The results showed that regardless of the training condition, all participants improved their capacity to learn face–name associations. A significant amelioration was also observed in participant satisfaction regarding their memory functioning and in the frequency with which the participants used strategies to support memory functions in daily life. The absence of difference between groups on all variables might be partly explained by the high variability of scores within the experimental group. Other studies are needed in order to verify the efficacy of EL learning and SR over EF in MCI-A.

Swimming performance, metabolic rates, and their correlates in the Iceland scallop Chlamys islandica.

The dramatic escape response of some scallops is modified by reproductive investment and by acclimation temperature. Despite considerable knowledge of the physiology of the escape response, functional links between escape response performance, organismal rates of oxygen uptake, and tissue metabolic capacities are little known. We measured oxygen consumption rates (standard, maximal, and aerobic scope), escape behavior (initial and repeat performance), tissue mass, condition index, protein content, and tissue metabolic capacities in the Iceland scallop Chlamys islandica to examine links between these parameters. Postexercise oxygen consumption rates were positively linked to contraction rate (repeat test) and to pyruvate kinase activity in the adductor muscle but negatively linked to digestive gland wet mass. Swimming behavior was mainly related to activity of glycolytic enzymes, and enzymatic activities were related to anatomic parameters. Scallop behavior and physiology change with size, both within our samples and on a larger scale. Small scallops showed more intense swimming activity and had higher arginine kinase activities but lower glycolytic enzyme activities in their adductor muscle than larger scallops. This corresponds to the ontogenetic change in susceptibility to predation and in habitat use observed in C. islandica.

Swimming away or clamming up: the use of phasic and tonic adductor muscles during escape responses varies with shell morphology in scallops

SUMMARY The simple locomotor system of scallops facilitates the study of muscle use during locomotion. We compared five species of scallops with different shell morphologies to see whether shell morphology and muscle use change in parallel or whether muscle use can compensate for morphological constraints. Force recordings during escape responses revealed that the use of tonic and phasic contractions varied markedly among species. The active species, Amusium balloti, Placopecten magellanicus and Pecten fumatus, made more phasic contractions than the more sedentary species, Mimachlamys asperrima and Crassadoma gigantea. Tonic contractions varied considerably among these species, with the two more sedentary species often starting their response to the predator with a tonic contraction and the more active species using shorter tonic contractions between series of phasic contractions. Placopecten magellanicus made extensive use of short tonic contractions. Pecten fumatus mounted an intense series of phasic contractions at the start of its response, perhaps to overcome the constraints of its unfavourable shell morphology. Valve closure by the more sedentary species suggests that their shell morphology protects them against predation, whereas swimming by the more active species relies upon intense phasic contractions together with favourable shell characteristics.

Scallops Show That Muscle Metabolic Capacities Reflect Locomotor Style and Morphology

Although all scallops swim using their adductor muscle to close their valves, scallop species differ considerably in how they use their muscle during escape responses, in parallel with the striking interspecific differences in shell morphology. This provides an excellent opportunity to study links between muscle metabolic capacities and animal performance. We found that the capacity for anaerobic glycolysis and aerobic metabolism, as well as phosphoarginine levels in the phasic adductor muscle, differ with escape response strategy. Phosphoarginine contents were high in species that rely on phasic contractions (Amusium balloti, Placopecten magellanicus, and Pecten fumatus). Arginine kinase activities reflect reliance on rapid initial bursts of phasic contractions. Scallops that maintain their valves in a closed position for prolonged periods (P. fumatus, Mimachlamys asperrima, and Crassadoma gigantea) have high activities of enzymes of anaerobic glycolysis in their phasic adductor muscle. Myosin ATPase activity was lower in the nonswimming scallop, C. gigantea, than in swimming scallops. The different patterns and roles of swimming are reflected in interspecific differences in the biochemical attributes of the phasic adductor muscle. These patterns suggest coevolution of muscle metabolic capacities, patterns of adductor muscle use, and shell morphology in scallops.

Differentiation of the pattern of cognitive impairment between depressed and non-depressed patients with dementia living in long-term care facilities

Objective: The principal objective of this study is to examine the cognitive profile of patients with dementia plus (D+ group) and without (D− group) concomitant depression. Method: The D+ (N = 61) and D− (N = 89) patients were recruited in long-term care facilities. The depression status of the participants was determined using the Cornell Scale for Depression in Dementia. Cognitive functioning was assessed using the Hierarchic Dementia Scale (HDS). Results: The analyses first indicated that on the total HDS score, patients of the D+ group exhibited more severe cognitive impairment compared to those of the D− group. Further analyses revealed that the difference between groups pertained to perception, attention/memory, calculation, and language functions. Moreover, secondary analyses revealed that the cognitive deficits of the D+ group were associated with behavioral (agitation and retardation, in particular), but not with mood-related, symptoms of depression. Interestingly, ideational symptoms of depression (suicide and self-depreciation, in particular) were positively correlated with cognitive impairment. Conclusion: These findings add to those of previous studies showing that D+ and D− patients differ not only regarding the presence or absence of depressive symptoms, but also regarding cognitive manifestations. This study thus reinforces the need to detect and treat accurately depression in dementia.

When Behavior and Mechanics Meet: Scallop Swimming Capacities and Their Hinge Ligament

ABSTRACT Scallops swim using jet propulsion produced by expulsion of water from between the valves by rapid contraction of the adductor muscle. The valves are subsequently opened by a ligament that acts like a spring mechanism. Compared with burrowing or sessile bivalves, scallops have ligaments with greater resilience. To determine whether the ligament resilience, ligament opening force, and force deployed by the phasic and tonic adductor muscles varied with escape response strategies and shell morphology, these properties were compared in scallops (Amusium balloti, Placopecten magellanicus, Equichlamys bifrons, Pecten fumatus, Mimachlamys asperrima, and Crassadoma gigantea) with differing life habits and morphologies. The ligament opening force varied among species and was always equal to or exceeded by phasic and tonic closing forces. The species producing the greatest frequency of phasic contractions (P. fumatus) had the greatest ligament resilience.

Swimming in Scallops

Abstract Pectinids are among the few bivalves that swim, with the prime motivation of escaping their predators. Swimming engages the large adductor muscle to close the valves, the hinge ligament to open them after muscle relaxation and the muscular mantle to direct the jets. In this chapter, the impact of shell characteristics on scallop swimming, the biomechanics of swimming, ligament properties, observations of swimming in nature, visual observations of escape responses in the laboratory, physiological examinations of escape response performance and biochemical mechanisms supporting swimming are reviewed. Swimming is generally a burst activity, with maximal distances of

Possible Prediction of Scallop Swimming Styles from Shell and Adductor Muscle Morphology

ABSTRACT Modifications in shell structure, mantle, and adductor muscle are considered derived adaptations that allowed scallops to swim. This suggests that morphological properties of the adductor muscle and shell should relate to swimming performance in scallops. Various morphological characteristics of the shell (mass, aspect ratio, and volume between the valves) and the adductor muscle (size, position, and attachment to the shell) were measured in six scallop species (Amusium balloti, Placopecten magellanicus, Equichlamys bifrons, Pecten fumatus, Mimachlamys asperrima, and Crassadoma gigantea) with distinct swimming strategies, as documented by measurements of muscle use during induced escape responses. Morphological characteristics of the shell and adductor muscle differed markedly between the species, but did not always follow their swimming strategies. Principal components analysis revealed that shell width, shell and muscle masses, and associated morphological attributes were closely linked with swimming endurance. The intensity of the escape response was best predicted by the aspect ratio and the obliqueness of the adductor muscle.

ARE BIOENERGETIC PROPERTIES LINKED WITH SHELL FLUCTUATING ASYMMETRY AND HETEROZYGOSITY IN ICELAND SCALLOP, CHLAMYS ISLANDICA?

Abstract We investigated the relationship between physiological properties, swimming performance, shell fluctuating asymmetry, and heterozygosity at allozyme loci in the Iceland scallop, Chlamys islandica, in an attempt to describe potential physiological mechanisms for the negative relationship between shell fluctuating asymmetry and survival of this species in pearl nets (Fréchette & Daigle 2002). No clear relationship was observed between shell fluctuating asymmetry and the different physiological and genetic parameters, although the maximum number of contractions in a series during escape tests and the specific activity of arginine kinase in the adductor muscle were linked with shell asymmetry before the application of corrections for multiple comparisons. Pyruvate kinase activity in soft tissues was higher in animals that were heterozygous at 2 loci compared with those that were heterozygous at 4 loci. Although our exploratory study suggests that shell asymmetry may reflect bioenergetic difficulties, further study is required to confirm such links.