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1.
Int J Drug Policy ; 97: 103208, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34058669

RESUMEN

BACKGROUND: In the Canadian Province of British Columbia (BC), the BC Mental Health Act permits involuntary care for treating mental disorders. However, the Act has also been applied to provide involuntary care to individuals with a primary substance use disorder, in the absence of specific guidelines and legislation, and with insufficient understanding of perspectives of people who use drugs (PWUD) regarding this approach. METHODS: As part of a larger mixed-methods research project providing an overview of involuntary care for severe substance use disorders in BC, three focus groups were convened with: PWUD, families and caregivers, and Indigenous community stakeholders. This analysis examines perspectives from the focus group of PWUD, consisting of nine participants from local and regional drug user and advocacy organizations regarding involuntary care. A qualitative descriptive approach and thematic analysis were conducted, using a coding framework developed deductively and inductively, and participant perspectives were interpreted drawing on problematization theory. RESULTS: Participants did not endorse the use of involuntary care, instead emphasizing significant changes were needed to address shortcomings of the wider voluntary care system. When asked to conceptualize what an acceptable involuntary care scenario might look like (under hypothetical and ideal conditions), participants recommended it should include: individual control and autonomy, peer advocacy in decision-making, and elimination of police and criminal justice system involvement from treatment encounters. Participants saw involuntary care to be an inappropriate approach given the shortcomings of the current system, noting also problems inherent in its use to manage severe SUDs and imminent harm, and prioritized alternate approaches to offsetting risks. CONCLUSION: Improving voluntary care for substance use, along with addressing the social determinants of health that put individuals at risk of problematic substance use and harm, were prioritized in participant perspectives. Participant comments regarding the use of involuntary care bring forward alternate solutions in the context of the opioid overdose crisis, and a reconceptualization of the 'problem' of managing severe substance use disorders.


Asunto(s)
Sobredosis de Droga , Consumidores de Drogas , Preparaciones Farmacéuticas , Trastornos Relacionados con Sustancias , Colombia Británica , Humanos , Trastornos Relacionados con Sustancias/terapia
2.
Pest Manag Sci ; 61(7): 619-26, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15880684

RESUMEN

Recent developments of new families of pesticides and growing awareness of the importance of wild pollinators for crop pollination have stimulated interest in potential effects of novel pesticides on wild bees. Yet pesticide toxicity studies on wild bees remain rare, and few studies have included long-term monitoring of bumble bee colonies or testing of foraging ability after pesticide exposure. Larval bees feeding on exogenous pollen and exposed to pesticides during development may result in lethal or sub-lethal effects during the adult stage. We tested the effects of a naturally derived biopesticide, spinosad, on bumble bee (Bombus impatiens Cresson) colony health, including adult mortality, brood development, weights of emerging bees and foraging efficiency of adults that underwent larval development during exposure to spinosad. We monitored colonies from an early stage, over a 10-week period, and fed spinosad to colonies in pollen at four levels: control, 0.2, 0.8 and 8.0 mg kg(-1), during weeks 2 through 5 of the experiment. At concentrations that bees would likely encounter in pollen in the wild (0.2-0.8 mg kg(-1)) we detected minimal negative effects to bumble bee colonies. Brood and adult mortality was high at 8.0 mg kg(-1) spinosad, about twice the level that bees would be exposed to in a 'worst case' field scenario, resulting in colony death two to four weeks after initial pesticide exposure. At more realistic concentrations there were potentially important sub-lethal effects. Adult worker bees exposed to spinosad during larval development at 0.8 mg kg(-1) were slower foragers on artificial complex flower arrays than bees from low or no spinosad treated colonies. Inclusion of similar sub-lethal assays to detect effects of pesticides on pollinators would aid in development of environmentally responsible pest management strategies.


Asunto(s)
Abejas/efectos de los fármacos , Insecticidas/toxicidad , Macrólidos/toxicidad , Animales , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Conducta Alimentaria/efectos de los fármacos , Larva/efectos de los fármacos
3.
Oecologia ; 48(3): 407-413, 1981 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28309760

RESUMEN

Intra-colony demography and life history characteristics of neotropical Africanized and temperate European honey bearaces were compared under simulated feral conditions. Major differences in colony demography were found which nevertheless resulted in some similar reproductive characteristics. European colonies were larger than Africanized colonies, had more rapid initral growth rates of worker populations, showed better survivorship of brood and adult workers, and differed in patterns of worker age distribution. However, both races were similar in the brood and adult populations when colonies swarmed, the frequency and timing of swarming, and the number of workers in prime swarms. The factors most important in determining these colony growth and reproductive patterns were likely worker mortality rates, climate, and resource availability.

4.
J Econ Entomol ; 97(4): 1384-9, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15384352

RESUMEN

Experiments were conducted in commercial tomato, Lycopersicon esculentum Miller (Solanaceae), greenhouses to compare the relative foraging effort of two bumble bee species, Bombus occidentalis Greene and Bombus impatiens Cresson, to examine interspecific competition between B. occidentalis and B. impatiens, and to determine whether bumble bee colonies grew to their full population potential in commercial tomato greenhouses. B. impatiens colonies had more brood and workers and made more foraging trips per hour than B. occidentalis colonies. However, B. impatiens returned to the colony without pollen loads and left their colonies without dropping off their pollen loads more frequently than B. occidentalis greenhouse colonies. Our data also suggest that the presence of B. impatiens had a detrimental effect on B. occidentalis populations. Furthermore, B. occidentalis colonies did not grow to their full population potential in tomato greenhouses, with fewer workers in greenhouse colonies than in colonies placed outside in a natural environment, or in colonies that were physically enclosed and protected from external mortality. Together, this study suggests that B. impatiens is a better pollinator than B. occidentalis. It also shows that unknown factors are limiting the size of B. occidentalis colonies in tomato greenhouses.


Asunto(s)
Agricultura/métodos , Abejas/crecimiento & desarrollo , Solanum lycopersicum , Agricultura/instrumentación , Animales , Abejas/fisiología , Polen , Especificidad de la Especie
5.
J Econ Entomol ; 96(3): 547-54, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12852587

RESUMEN

Although commercially reared colonies of bumble bees (Bombus sp.) are the primary pollinator world-wide for greenhouse tomatoes (Lycopersicon esculentum Mill.) previous research indicates that honey bees (Apis mellifera L.) might be a feasible alternative or supplement to bumble bee pollination. However, management methods for honey bee greenhouse tomato pollination scarcely have been explored. We 1) tested the effect of initial amounts of brood on colony population size and flight activity in screened greenhouses during the winter, and 2) compared foraging from colonies with brood used within screened and unscreened greenhouses during the summer. Brood rearing was maintained at low levels in both brood and no-brood colonies after 21 d during the winter, and emerging honey bees from both treatments had significantly lower weights than bees from outdoor colonies. Honey bee flight activity throughout the day and over the 21 d in the greenhouse was not influenced by initial brood level. In our summer experiment, brood production in screened greenhouses neared zero after 21 d but higher levels of brood were reared in unscreened greenhouses with access to outside forage. Flower visitation measured throughout the day and over the 21 d the colonies were in the greenhouse was not influenced by screening treatment. An economic analysis indicated that managing honey bees for greenhouse tomato pollination would be financially viable for both beekeepers and growers. We conclude that honey bees can be successfully managed for greenhouse tomato pollination in both screened and unscreened greenhouses if the foraging force is maintained by replacing colonies every 3 wk.


Asunto(s)
Agricultura/métodos , Abejas/fisiología , Fertilización/fisiología , Polen/fisiología , Solanum lycopersicum/fisiología , Agricultura/economía , Agricultura/instrumentación , Animales , Peso Corporal , Productos Agrícolas/economía , Productos Agrícolas/fisiología , Vuelo Animal , Flores/fisiología , Solanum lycopersicum/economía , Dinámica Poblacional , Estaciones del Año
6.
J Econ Entomol ; 95(2): 221-6, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12019993

RESUMEN

Two major parasitic pests threaten honey bee populations, the external mite Varroa destructor and the internal mite Acarapis woodi (Rennie). Varroa are beginning to develop resistance to the main chemical defense fluvalinate, and alternative control methods are being pursued. Previous studies have shown that botanical oils, especially thymol, can be effective. Six release devices for either thymol or a blend of botanical oils known as Magic 3 were tested in beehives. The release devices were as follows: (1) low density polyethylene (LDPE) sleeves filled with Magic 3, (2) Magic 3-infused florist blocks, (3) thymol infused florist blocks, (4) a canola oil and thymol mixture wick release, (5) a plastic strip coated with calcium carbonate and Magic 3, and (6) an untreated control. There were significant decreases in varroa levels with the use of Magic 3 sleeves, but brood levels also decreased. Tracheal mite levels significantly decreased with the Magic 3 sleeve treatment, the Magic 3 florist block treatment, and the thymol canola wick treatment. A second experiment showed that changing the location of Magic 3 sleeves in the colony did not detrimentally effect brood levels, but also did not effectively control varroa mites.


Asunto(s)
Abejas/parasitología , Infestaciones por Ácaros/veterinaria , Ácaros/efectos de los fármacos , Aceites de Plantas/farmacología , Timol/farmacología , Control de Ácaros y Garrapatas/métodos , Animales , Infestaciones por Ácaros/prevención & control
7.
J Econ Entomol ; 97(2): 163-70, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15154432

RESUMEN

This study examined the use of honey bees, Apis mellifera L., to supplement bumble bee, Bombus spp., pollination in commercial tomato, Lycopersicon esculentum Miller, greenhouses in Western Canada. Honey bee colonies were brought into greenhouses already containing bumble bees and left for 1 wk to acclimatize. The following week, counts of honey and bumble bees foraging and flying throughout the greenhouse were conducted three times per day, and tomato flowers open during honey bee pollination were marked for later fruit harvest. The same counts and flower-marking also were done before and after the presence of honey bees to determine the background level of bumble bee pollination. Overall, tomato size was not affected by the addition of honey bees, but in one greenhouse significantly larger tomatoes were produced with honey bees present compared with bumble bees alone. In that greenhouse, honey bee foraging was greater than in the other greenhouses. Honey bees generally foraged within 100 m of their colony in all greenhouses. Our study invites further research to examine the use of honey bees with reduced levels of bumble bees, or as sole pollinators of greenhouse tomatoes. We also make specific recommendations for how honey bees can best be managed in greenhouses.


Asunto(s)
Abejas/fisiología , Polen/fisiología , Estaciones del Año , Solanum lycopersicum/crecimiento & desarrollo , Agricultura/métodos , Animales , Canadá , Densidad de Población
8.
J Econ Entomol ; 97(2): 369-73, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15154457

RESUMEN

We conducted laboratory experiments to investigate the lethal and sublethal effects of clothianidin on bumble bee, Bombus impatiens Cresson, colony health and foraging ability. Bumble bee colonies were exposed to 6 ppb clothianidin, representing the highest residue levels found in field studies on pollen, and a higher dose of 36 ppb clothianidin in pollen. Clothianidin did not effect pollen consumption, newly emerged worker weights, amount of brood or the number of workers, males, and queens at either dose. The foraging ability of worker bees tested on an artificial array of complex flowers also did not differ among treatments. These results suggest that clothianidin residues found in seed-treated canola and possibly other crops will not adversely affect the health of bumble bee colonies or the foraging ability of workers.


Asunto(s)
Abejas/efectos de los fármacos , Abejas/fisiología , Guanidinas/farmacología , Insecticidas/farmacología , Animales , Conducta Animal/efectos de los fármacos , Neonicotinoides , Residuos de Plaguicidas/análisis , Polen/química , Tiazoles
9.
Mol Ecol ; 16(22): 4837-48, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17927707

RESUMEN

A key characteristic of eusocial species is reproductive division of labour. Honey bee colonies typically have a single reproductive queen and thousands of sterile workers. Adult queens differ dramatically from workers in anatomy, physiology, behaviour and lifespan. Young female workers can activate their ovaries and initiate egg laying; these 'reproductive' workers differ from sterile workers in anatomy, physiology, and behaviour. These differences, however, are on a much smaller scale than those observed between the queen and worker castes. Here, we use microarrays to monitor expression patterns of several thousand genes in the brains of same-aged virgin queens, sterile workers, and reproductive workers. We found large differences in expression between queens and both worker groups (~2000 genes), and much smaller differences between sterile and reproductive workers (221 genes). The expression patterns of these 221 genes in reproductive workers are more queen-like, and may represent a core group of genes associated with reproductive physiology. Furthermore, queens and reproductive workers preferentially up-regulate genes associated with the nurse bee behavioural state, which supports the hypothesis of an evolutionary link between worker division of labour and molecular pathways related to reproduction. Finally, several functional groups of genes associated with longevity in other species are significantly up-regulated in queens. Identifying the genes that underlie the differences between queens, sterile workers, and reproductive workers will allow us to begin to characterize the molecular mechanisms underlying the evolution of social behaviour and large-scale remodelling of gene networks associated with polyphenisms.


Asunto(s)
Abejas/genética , Encéfalo/metabolismo , Expresión Génica , Conducta Sexual Animal , Predominio Social , Animales , Abejas/fisiología , Femenino , Perfilación de la Expresión Génica , Masculino , Análisis de Secuencia por Matrices de Oligonucleótidos , Feromonas/genética , Feromonas/metabolismo , Vitelogeninas/genética , Vitelogeninas/metabolismo
10.
J Comp Physiol B ; 176(1): 55-63, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16228242

RESUMEN

We examined the effect of larval and adult nutrition on worker honey bee (Apis mellifera L.) ovary development. Workers were fed high or low-pollen diets as larvae, and high or low-protein diets as adults. Workers fed low-protein diets at both life stages had the lowest levels of ovary development, followed by those fed high-protein diets as larvae and low- quality diets as adults, and then those fed diets poor in protein as larvae but high as adults. Workers fed high-protein diets at both life stages had the highest levels of ovary development. The increases in ovary development due to improved dietary protein in the larval and adult life stages were additive. Adult diet also had an effect on body mass. The results demonstrate that both carry-over of larval reserves and nutrients acquired in the adult life stage are important to ovary development in worker honey bees. Carry-over from larval development, however, appears to be less important to adult fecundity than is adult nutrition. Seasonal trends in worker ovary development and mass were examined throughout the brood rearing season. Worker ovary development was lowest in spring, highest in mid-summer, and intermediate in fall.


Asunto(s)
Abejas/crecimiento & desarrollo , Dieta , Ovario/crecimiento & desarrollo , Animales , Peso Corporal , Proteínas en la Dieta , Femenino , Larva/crecimiento & desarrollo , Fenómenos Fisiológicos de la Nutrición , Tamaño de los Órganos , Estaciones del Año
11.
J Chem Ecol ; 31(11): 2731-45, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16273438

RESUMEN

Recent studies have demonstrated a remarkable and unexpected complexity in social insect pheromone communication, particularly for honeybees (Apis mellifera L.). The intricate interactions characteristic of social insects demand a complex language, based on specialized chemical signals that provide a syntax that is deeper in complexity and richer in nuance than previously imagined. Here, we discuss this rapidly evolving field for honeybees, the only social insect for which any primer pheromones have been identified. Novel research has demonstrated the importance of complexity, synergy, context, and dose, mediated through spatial and temporal pheromone distribution, and has revealed an unprecedented wealth of identified semiochemicals and functions. These new results demand fresh terminology, and we propose adding "colony pheromone" and "passenger pheromone" to the current terms sociochemical, releaser, and primer pheromone to better encompass our growing understanding of chemical communication in social insects.


Asunto(s)
Comunicación Animal , Abejas/fisiología , Feromonas/fisiología , Animales , Femenino , Masculino , Feromonas/química , Conducta Social
12.
J Invertebr Pathol ; 84(1): 54-8, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-13678713

RESUMEN

We examined the effects of Nosema bombi (Microsporidia: Nosematidae) on colonies of bumble bees, Bombus occidentalis Greene (Hymenoptera: Apidae), used to pollinate tomatoes in commercial greenhouses. We assessed methods of detecting N. bombi and tested the effectiveness of fumagillin to control this parasite. N. bombi did not affect adult population size or amount of brood in B. occidentalis colonies. Fumagillin was not effective against N. bombi at the doses we tested, and frass samples did not provide accurate estimates of the intensity of N. bombi infections. The number of N. bombi spores per bee was highly variable among bumble bees within colonies, and accurate estimates could only be obtained by sampling a large proportion of bees in each colony. Therefore, whole bee and frass sampling is useful for determining if N. bombi is present or absent, but not for obtaining accurate estimates of the intensity of N. bombi infections.


Asunto(s)
Antiprotozoarios/farmacología , Abejas/parasitología , Ácidos Grasos Insaturados/farmacología , Nosema/efectos de los fármacos , Nosema/fisiología , Animales , Ciclohexanos , Interacciones Huésped-Parásitos , Microsporidiosis/tratamiento farmacológico , Sesquiterpenos
13.
Proc Natl Acad Sci U S A ; 100(8): 4486-91, 2003 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-12676987

RESUMEN

The honey bee queen produces pheromones that function in both releaser and primer roles such as attracting a retinue of workers around her, attracting drones on mating flights, preventing workers from reproducing at the individual (worker egg-laying) and colony (swarming) level, and regulating several other aspects of colony functioning. The queen mandibular pheromone (QMP), consisting of five synergistic components, is the only pheromone chemically identified in the honey bee (Apis mellifera L.) queen, but this pheromone does not fully duplicate the pheromonal activity of a full queen extract. To identify the remaining unknown compounds for retinue attraction, honey bee colonies were selectively bred to have low response to synthetic QMP and high response to a queen extract in a laboratory retinue bioassay. Workers from these colonies were then used in the bioassay to guide the isolation and identification of the remaining active components. Four new compounds were identified from several glandular sources that account for the majority of the difference in retinue attraction between synthetic QMP and queen extract: methyl (Z)-octadec-9-enoate (methyl oleate), (E)-3-(4-hydroxy-3-methoxyphenyl)-prop-2-en-1-ol (coniferyl alcohol), hexadecan-1-ol, and (Z9,Z12,Z15)-octadeca-9,12,15-trienoic acid (linolenic acid). These compounds were inactive alone or in combination, and they only elicited attraction in the presence of QMP. There was still unidentified activity remaining in the queen extract. The queen therefore produces a synergistic, multiglandular pheromone blend of at least nine compounds for retinue attraction, the most complex pheromone blend known for inducing a single behavior in any organism.


Asunto(s)
Abejas/química , Hormonas de Insectos/química , Feromonas/química , Animales , Abejas/fisiología , Cromatografía Líquida de Alta Presión , Femenino , Cromatografía de Gases y Espectrometría de Masas , Hormonas de Insectos/aislamiento & purificación , Hormonas de Insectos/fisiología , Masculino , Feromonas/aislamiento & purificación , Feromonas/fisiología , Conducta Social
14.
Naturwissenschaften ; 90(10): 477-80, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14564409

RESUMEN

We report results that address a long-standing controversy in honey bee biology, the identity of the queen-produced compounds that inhibit worker honey bee ovary development. As the honey bee is the only organism for which identities have been proposed for any pheromone that regulates reproduction, the resolution of its identity is of broad significance. We examined the effects of synthetic honey bee queen mandibular pheromone (QMP), four newly identified queen retinue pheromone components, and whole-queen extracts on the ovary development of caged worker bees. The newly identified compounds did not inhibit worker ovary development alone, nor did they improve the efficacy of QMP when applied in combination. QMP was as effective as queen extracts at ovary regulation. Caged workers in the QMP and queen extract treatments had better developed ovaries than did workers remaining in queenright colonies. We conclude that QMP is responsible for the ovary-regulating pheromonal capability of queens from European-derived Apis mellifera subspecies.


Asunto(s)
Abejas/fisiología , Feromonas/fisiología , Animales , Femenino , Miel , Ovario/crecimiento & desarrollo , Feromonas/aislamiento & purificación , Feromonas/farmacología , Conducta Social
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