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1.
J Econ Entomol ; 115(6): 2061-2067, 2022 12 14.
Article in English | MEDLINE | ID: mdl-36178336

ABSTRACT

The province of Quebec, Canada is the most important organic cranberry growing region worldwide. However, insect pest management methods are limited, and growers face significant yield loss each year, mostly caused by lepidopteran pests. Egg parasitoids of the genus Trichogramma (Hymenoptera: Trichogrammatidae) are effective biocontrol agents of lepidopteran pests in many forests and agricultural systems. Herein, a two-year, large-scale population survey of Trichogramma spp. was performed using Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) as sentinel eggs in Quebec organic cranberry bogs. Collected specimens were identified by sequencing ribosomal DNA of the Internal Transcribed Spacer 2 (ITS-2) region and subjected to resemblance analysis with reference specimens for identification. Our results confirm that at least four Trichogramma species naturally occur in the studied agroecosystem. Those species are T. brassicae Bezdenko, T. minutum Riley, T. ostriniae (Pang et Chen), and T. pretiosum Riley. While some species have already been reported in cranberry bogs, this represents the first mention of T. brassicae and T. ostriniae as well as the first mention of T. minutum in Quebec cranberry bogs. All species collected are native from Eastern Canada except T. ostriniae. These species can be considered as biocontrol agent candidates for cranberry lepidopteran pests, but further efficacy trials are needed to identify the best species for each pest.


Subject(s)
Hymenoptera , Moths , Vaccinium macrocarpon , Wasps , Animals , Quebec , DNA, Ribosomal , Wetlands , Moths/genetics , Sequence Analysis , Wasps/genetics , Ovum , Pest Control, Biological/methods
2.
J Econ Entomol ; 109(6): 2463-2471, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-27694183

ABSTRACT

The zoophytophagous mullein bug, Campylomma verbasci (Meyer-Dür) (Hemiptera: Miridae), is a beneficial predator of mites and aphids, but also a pest causing damage when it feeds on apples. The aim of this study was to evaluate three different parameters of phytophagy of the mullein bug both in laboratory (phytophagous behavior) and field (fruit damage) tests: 1) apple cultivar, 2) fruit size, and 3) nymphal instar. In the laboratory, nymphs were observed individually for 15 min in Petri dishes containing agar gel and an apple fruitlet to evaluate feeding punctures of four apple cultivars, four fruit sizes, and five nymphal instars. In the orchard, nymphs were caged at bloom in sleeve cages to evaluate damage on the developing fruit of seven apple cultivars and three nymphal instars on 'Red Delicious'. The feeding punctures in the laboratory were higher on 'Red Delicious' than on 'Honeycrisp'; fruit damage in the orchard did not differ among cultivars at mid-season, but was higher on 'Red Delicious' than on 'Lobo' and 'Marshall McIntosh' at harvest. The number of feeding punctures in the laboratory was higher on 7-9 mm than on 18-20 mm size fruit for 'Red Delicious', but not for 'Honeycrisp'. The number of feeding punctures in the laboratory made by the fifth nymphal instar was higher than those made by younger nymphs, but fruit damage in the orchard did not differ among nymphal instars. Our results will help to elaborate a management chart for this insect by minimizing risks and promoting its use for biocontrol. RÉSUMÉ: .La punaise de la molène, Campylomma verbasci (Meyer-Dür) (Hemiptera: Miridae), est un prédateur bénéfique zoophytophage des acariens et pucerons dans les vergers, mais également un ravageur causant des dommages lorsqu'il se nourrit sur les pommes. Le but de cette étude était d'évaluer trois paramètres différents sur la phytophagie de la punaise de la molène, à la fois en laboratoire (comportement phytophage) et sur le terrain (dommages aux fruits) : 1) les cultivars de pommes, 2) la taille des fruits, et 3) les stades larvaires. En laboratoire, les larves étaient observées individuellement pendant 15 min dans des boites de Petri contenant un gel d'agar et une jeune pomme afin de déterminer les piqûres de nutrition sur quatre cultivars de pommes, quatre tailles de fruit et cinq stades larvaires différents. En verger, des larves ont été encagées à la floraison dans des manchons en mousseline afin d'évaluer les dommages sur les fruits en développement. Les essais ont été effectués sur sept cultivars de pommes ainsi qu'avec trois stades larvaires sur le cultivar "Délicieuse rouge". Les piqûres de nutrition en laboratoire étaient plus nombreuses sur "Délicieuse rouge" que sur "Honeycrisp"; les dommages aux fruits en verger ne différaient pas entre les cultivars à mi-saison, mais étaient plus nombreux sur "Délicieuse rouge" que sur "Lobo" et "Marshall McIntosh" à la récolte. Les piqûres de nutrition en laboratoire étaient plus nombreuses pour la taille de fruit 7-9 mm que 18-20 mm sur "Délicieuse rouge", mais pas sur "Honeycrisp". Le nombre de piqûres de nutrition (en laboratoire) faites par les larves de stade 5 étaient plus nombreuses que celles faites par les larves plus jeunes, mais les dommages aux fruits (en verger) ne différaient pas entre les stades larvaires. Ces résultats vont aider à élaborer une charte de gestion de cet insecte en minimisant les risques et en favorisant son rôle d'agent de lutte biologique.


Subject(s)
Herbivory , Heteroptera/physiology , Malus/physiology , Animals , Feeding Behavior , Heteroptera/growth & development , Nymph/growth & development , Nymph/physiology
3.
J Biomech Eng ; 129(6): 825-37, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18067386

ABSTRACT

With the worldwide prevalence of cardiovascular diseases, much attention has been focused on simulating the characteristics of the human heart to better understand and treat cardiac disorders. The purpose of this study is to build a finite element model of the left atrium (LA) that incorporates detailed anatomical features and realistic material characteristics to investigate the interaction of heart tissue and surgical instruments. This model is used to facilitate the design of an endoscopically deployable atrial retractor for use in minimally invasive, robotically assisted mitral valve repair. Magnetic resonance imaging (MRI) scans of a pressurized explanted porcine heart were taken to provide a 3D solid model of the heart geometry, while uniaxial tensile tests of porcine left atrial tissue were conducted to obtain realistic material properties for noncontractile cardiac tissue. A finite element model of the LA was constructed using ANSYS Release 9.0 software and the MRI data. The Mooney-Rivlin hyperelastic material model was chosen to characterize the passive left atrial tissue; material constants were derived from tensile test data. Finite element analysis (FEA) models of a CardioVations Port Access retractor and a prototype endoscopic retractor were constructed to simulate interaction between each instrument and the LA. These contact simulations were used to compare the quality of retraction between the two instruments and to optimize the design of the prototype retractor. Model accuracy was verified by comparing simulated cardiac wall deflections to those measured by MRI. FEA simulations revealed that peak forces of approximately 2.85 N and 2.46 N were required to retract the LA using the Port Access and prototype retractors, respectively. These forces varied nonlinearly with retractor blade displacement. Dilation of the atrial walls and rigid body motion of the chamber were approximately the same for both retractors. Finite element analysis is shown to be an effective tool for analyzing instrument/tissue interactions and for designing surgical instruments. The benefits of this approach to medical device design are significant when compared to the alternatives: constructing prototypes and evaluating them via animal or clinical trials.


Subject(s)
Atrial Function, Left/physiology , Cardiac Surgical Procedures/instrumentation , Finite Element Analysis , Surgical Instruments , Animals , Cardiac Surgical Procedures/methods , Equipment Design , Heart Atria/anatomy & histology , Heart Valve Diseases/surgery , Humans , Imaging, Three-Dimensional , Insufflation , Magnetic Resonance Imaging , Minimally Invasive Surgical Procedures/instrumentation , Mitral Valve/physiopathology , Mitral Valve/surgery , Models, Cardiovascular , Motion , Movement/physiology , Robotics/methods , Swine , Tensile Strength
4.
Phys Rev Lett ; 87(15): 153402, 2001 Oct 08.
Article in English | MEDLINE | ID: mdl-11580697

ABSTRACT

The stability of multiply charged sodium clusters Na(q+)(n) (q< or =10) produced in collisions between neutral clusters and multiply charged ions A(z+) ( z = 1 to 28) is experimentally investigated. Multiply charged clusters are formed within a large range of temperatures and fissilities. They are identified by means of a high-resolution reflectron-type time-of-flight mass spectrometer (m/deltam approximately 14 000). The maximum fissility of stable clusters is obtained for z = 28 and is X approximately 0.85+/-0.07, slightly below the Rayleigh limit (X = 1). It is mainly limited by the initial cluster temperature (T approximately 100 K).

5.
Phys Rev Lett ; 84(26 Pt 1): 5936-9, 2000 Jun 26.
Article in English | MEDLINE | ID: mdl-10991093

ABSTRACT

The accelerated expansion of the Universe measured by high redshift Type Ia supernova observations is explained using the nonequilibrium dynamics of naturally soft boson fields. Spinodal instabilities inevitably present in such systems yield a very attractive mechanism for arriving at the required equation of state at late times, while satisfying all the known constraints on models of quintessence.

7.
J Can Diet Assoc ; 55(3): 121-4, 1994.
Article in English | MEDLINE | ID: mdl-10137914

ABSTRACT

Although puréed diets are thought to be widely used for patients in long-term care facilities, there is little specific information concerning prevalence and reasons for the actual use of this diet texture. At Saint-Vincent Hospital, a 516 bed, long-term care and rehabilitation facility, 25.9% of the chronic-care population (n = 424) were on a puréed diet. Those who received puréed diets tended to be older (83.5 years versus 75.4 years, P < 0.001) and were more likely to be female (82.7% versus 70.8% P < 0.006), than the total population of long-term care patients. A greater percentage of patients receiving a puréed diet had dementia (43.0% versus 30.6%, P < 0.02), and fewer had cerebrovascular accident as a primary diagnosis (22.6% versus 33.9%, P < 0.05), than the total population of long-term care patients at this hospital. Following data collection, reasons for patients being on a puréed diet were grouped into five categories. The most popular categories were "Physiological/Mechanical" and "Cognitive" problems.


Subject(s)
Dietary Services/statistics & numerical data , Food Service, Hospital/statistics & numerical data , Aged , Efficiency, Organizational , Feeding and Eating Disorders , Food Preferences , Hospitals, Chronic Disease , Humans , Long-Term Care , Mental Disorders , Ontario , Safety Management
8.
J Am Acad Dermatol ; 27(5 Pt 2): 835-8, 1992 Nov.
Article in English | MEDLINE | ID: mdl-1469139

ABSTRACT

The petechial glove and sock syndrome is a recently described febrile dermatosis characterized by acral pruritus, edema, pain, petechiae, and an enanthem of petechiae and erosions; these features suggest a viral origin. We report a typical case in a 36-year-old woman. IgM antibodies to human parvovirus B19 (PVB19) were present, and acute and convalescent IgG antibodies demonstrated seroconversion, which suggested recent infection with PVB19. Results of tests for other viral and bacterial agents were negative. These results strongly implicate PVB19 as an etiologic agent in the petechial glove and sock syndrome.


Subject(s)
Erythema Infectiosum , Foot Dermatoses/microbiology , Hand Dermatoses/microbiology , Parvovirus B19, Human , Acute Disease , Adult , Erythema Infectiosum/pathology , Female , Foot Dermatoses/pathology , Hand Dermatoses/pathology , Humans , Syndrome
9.
J Clin Microbiol ; 29(12): 2865-7, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1757560

ABSTRACT

Paired serum samples from 93 patients suspected of having measles were assayed for measles virus-specific immunoglobulin M (IgM) antibodies by an enzyme immunoassay (EIA), and the results were compared with results from a complement fixation assay and an EIA for measles virus IgG. By using significant serologic rises as the standard for comparison, the IgM EIA assay had a sensitivity of 85.7%, a specificity of 81.3%, a positive predictive value of 95.7%, and a negative predictive value of 54.2%. This assay can be expected to perform well in outbreak situations.


Subject(s)
Immunoenzyme Techniques , Immunoglobulin M/blood , Measles virus/immunology , Measles/diagnosis , Complement Fixation Tests , False Negative Reactions , False Positive Reactions , Female , Humans , Immunoenzyme Techniques/standards , Immunoglobulin G/blood , Male , Reagent Kits, Diagnostic/standards , Sensitivity and Specificity
10.
J Pediatr ; 99(6): 880-6, 1981 Dec.
Article in English | MEDLINE | ID: mdl-6273517

ABSTRACT

To explore the association of Epstein-Barr virus infection with childhood pneumonia we studied two patients whose mononucleosis-like illnesses were accompanied by pneumonia; both had virologic and serologic evidence of current or recent EBV infection. We then analyzed the sera of 71 children (age range, 14 months to 9 years) with pulmonary infiltrates for the presence of four classes of antibody to EBV. Antibody responses consistent with current or recent EB virus infection were found in 15. Two children had IgM antibodies to the EBV viral antigen at titers greater than or equal to 1:160, indicating current infection, and all 15 patients had antibody to components of the early antigen complex, suggesting recent infection. A fourfold rise or drop in one or more EBV-specific antibody classes was noted in eight patients within 30 days following onset of clinical illness. Few patients had clinical features suggesting infectious mononucleosis. Eight of the 15 with serologic evidence of current or recent EBV infection also had clinical or serologic evidence of infection with another pathogen--bacterial, viral, or mycoplasmal. Thus, in childhood pneumonia, EBV may be a primary, co-primary, or secondary pathogen; it may be reactivated in the course of infection with another agent, or possibly, by suppressing immune function, it may precipitate infection with some other organism.


Subject(s)
Infectious Mononucleosis/complications , Pneumonia/complications , Adolescent , Antibodies, Viral/analysis , Child , Child, Preschool , Female , Herpesvirus 4, Human/immunology , Humans , Immunoglobulin M/analysis , Infant , Infectious Mononucleosis/immunology , Male , Pneumonia/etiology , Pneumonia/immunology , Pneumonia, Mycoplasma/immunology , Pneumonia, Viral/etiology , Pneumonia, Viral/immunology
11.
Drug Alcohol Depend ; 4(6): 475-87, 1979 Nov.
Article in French | MEDLINE | ID: mdl-520146

ABSTRACT

Is drug dependence more likely to establish itself in persons whose personality structure is already characterized by a psychological dependence which can be looked at from two aspects: cognitive field dependence and emotional dependence? Three groups of 21 subjects each, multiple drug users, users of cannabis and non-users, are studied with the expectation that the first group is more psychologically dependent than the second one, the latter being in turn more dependent than the group of non-users. The situation is not so simple. Hard-drug users appear to be more active than users of cannabis, whereas non-users are even more dynamic individuals. However, in such a study the duration of consumption exercise an important influence because, in this regard, different personality profiles of the two drug-using groups come into play, the users of cannabis presenting a more incoherent picture. The multiple drug addict selected from his natural environment seems to acquire, through his prolonged consumption, a greater perceptual independence and emotional maturity owing to the clandestine nature of his habit, and a more acute and articulate general way of functioning in order to avoid mishaps.


Subject(s)
Dependency, Psychological , Personality , Substance-Related Disorders/psychology , Adult , Cannabis , Humans , Illicit Drugs , Male , Personality Tests
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