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1.
J Helminthol ; 97: e41, 2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37194264

RESUMEN

Some slug species are considered a nuisance in agriculture and horticulture worldwide, causing economic losses to growers. Phasmarhabditis is a genus of bacteria-feeding nematodes that can parasitize slugs and snails and thus potentially serve as a biological control agent. Canada had no record of Phasmarhabditis until a survey conducted in 2019 reported a Canadian strain of Phasmarhabditis californica from a single Arion rufus slug. To build on this discovery, we surveyed three major agricultural sites, ten greenhouses, and nurseries in Alberta from June to September 2021 to collect pest slug species and investigate their associated nematodes, specifically P. californica. Slugs were collected from the field and returned to the laboratory to check for emerging nematodes on White traps. We collected 1331 slugs belonging to nine species, with Deroceras reticulatum being the most common. Only 45 (3.38%) slug samples were positive for nematodes, and the majority were identified to species level: Alloionema appendiculatum, Caenorhabditis briggsae, Caenorhabditis elegans, Panagrolaimus subelongatus, and Mesorhabditis spiculigera. We did not isolate P. californica from any of the slugs collected from these survey sites, which included the original site where P. californica was discovered. However, four D. reticulatum slugs retrieved from a residential garden sample were infected with P. californica. These findings suggest the possibility of a fragmented distribution of P. californica across Alberta. Future research should focus on extensively surveying agriculture and horticulture sites and residential gardens in different provinces across Canada.


Asunto(s)
Gastrópodos , Nematodos , Casas Cuna , Rhabditoidea , Humanos , Lactante , Animales , Alberta , Caracoles
2.
J Sports Sci ; 41(23): 2088-2120, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38350022

RESUMEN

This systematic review and meta-analysis aims to compare physiological, perceptual and biomechanical outcomes between walking on a treadmill and overground surfaces. Five databases (CINAHL, EMBASE, MEDLINE, SPORTDiscus, Web of Science) were searched until September 2022. Included studies needed to be a crossover design comparing biomechanical, physiological, or perceptual measures between motorised-treadmill and overground walking in healthy adults (18-65 years) walking at the same speed (<5% difference). The quality of studies were assessed using a modified Downs and Black Quality Index. Meta-analyses were performed to determine standardised mean difference ± 95% confidence intervals for all main outcome measures. Fifty-five studies were included with 1,005 participants. Relative oxygen consumption (standardised mean difference [95% confidence interval] 0.38 [0.14,0.63]) and cadence (0.22 [0.06,0.38]) are higher during treadmill walking. Whereas stride length (-0.36 [-0.62,-0.11]) and step length (-0.52 [-0.98,-0.06]) are lower during treadmill walking. Most kinetic variables are different between surfaces. The oxygen consumption, spatiotemporal and kinetic differences on the treadmill may be an attempt to increase stability due to the lack of control, discomfort and familiarity on the treadmill. Treadmill construction including surface stiffness and motor power are likely additional constraints that need to be considered and require investigation. This research was supported by an Australian Government Research Training Program (RTP) scholarship. Protocol registration is CRD42020208002 (PROSPERO International Prospective Register of Systematic Reviews) in October 2020.


Relative oxygen consumption is greater on a treadmill when compared with overground when walking at similar speeds and needs to be considered when prescribing exercise.Walking on a treadmill results in several biomechanical changes compared to overground that may be related to changes in gait stability.It may be favourable for rehabilitation purposes for people to initially walk on a treadmill due to lower vertical ground reaction force at push-off and lower joint moments at the knee and ankle.


Asunto(s)
Marcha , Caminata , Adulto , Humanos , Australia , Fenómenos Biomecánicos , Prueba de Esfuerzo/métodos , Marcha/fisiología , Caminata/fisiología
3.
J Phys Condens Matter ; 33(27)2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-33946062

RESUMEN

Dislocations often occur in thin films with large misfit strain as a result of strain energy accumulation and can drastically change the film properties. Here the structure and dislocations in oxide heterostructures with large misfit strain are investigated on atomic scale. When grown on SrTiO3(001), the dislocations in both the monolithic BaTiO3thin film and its superlattices with SrIrO3appear above a critical thickness around 6 nm. The edge component of the dislocations is seen in both cases with the Burgers vector ofa⟨100⟩. However, compared to monolithic BaTiO3, the dislocation density is slightly lower in BaTiO3/SrIrO3superlattices. In the superlattice, when considering the SrTiO3lattice constant as the reference, BaTiO3has a larger misfit strain comparing with SrIrO3. It is found that in both cases, the formation of dislocation is only affected by the critical thickness of the film with larger lattice misfit (BaTiO3), regardless of the existence of a strong octahedral tilt/rotation mismatch at BaTiO3/SrIrO3interface. Our findings suggest that it is possible to control the position of dislocations, an important step toward defect engineering.

4.
J Helminthol ; 94: e200, 2020 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-33046147

RESUMEN

A survey of nematodes associated with terrestrial slugs was conducted in residential gardens, nurseries, greenhouses and agricultural sites located in and around Edmonton, Alberta, Canada. A total of 2406 slugs were collected from 82 sites. Slugs were decapitated and cadavers were incubated for two weeks, with emerging nematodes removed and processed for identification. Nematodes were identified using molecular sequence data for the 18S ribosomal DNA. Nematodes were recovered from 20 of the 82 sites surveyed, with 24.4% of the slugs infected with nematodes. A total of seven nematodes were identified to species level, including Caenorhabditis elegans, Panagrolaimus papillosus, Pellioditis typica, Pelodera pseudoteres, Rhabditella axei, Rhabditoides inermiformis and Phasmarhabditis californica. An additional four specimens were identified to genus level, including Oscheius sp. (9), Pristionchus sp., Rhabditis sp. and Rhabditophanes sp. (1). The two most common nematode species were C. elegans and P. pseudoteres. The facultative parasite, P. californica, was recovered from a single Arion rufus specimen, collected from a seasonal nursery. To our knowledge, this study represents the first survey of slug-associated nematodes in Canada.


Asunto(s)
Gastrópodos/parasitología , Rabdítidos/clasificación , Alberta , Animales , ADN Ribosómico/genética , Rabdítidos/aislamiento & purificación , Infecciones por Rhabditida
5.
Appl Opt ; 59(10): 3285-3295, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32400613

RESUMEN

We present two prescriptions for broadband ($ {\sim} 77 - 252\;{\rm GHz} $), millimeter-wave antireflection coatings for cryogenic, sintered polycrystalline aluminum oxide optics: one for large-format (700 mm diameter) planar and plano-convex elements, the other for densely packed arrays of quasi-optical elements-in our case, 5 mm diameter half-spheres (called "lenslets"). The coatings comprise three layers of commercially available, polytetrafluoroethylene-based, dielectric sheet material. The lenslet coating is molded to fit the 150 mm diameter arrays directly, while the large-diameter lenses are coated using a tiled approach. We review the fabrication processes for both prescriptions, then discuss laboratory measurements of their transmittance and reflectance. In addition, we present the inferred refractive indices and loss tangents for the coating materials and the aluminum oxide substrate. We find that at 150 GHz and 300 K the large-format coating sample achieves $ (97 \pm 2)\% $ transmittance, and the lenslet coating sample achieves $ (94 \pm 3)\% $ transmittance.

6.
Parasitology ; 147(6): 659-666, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32046800

RESUMEN

Ascarid parasites infect a variety of hosts and regular anthelmintic treatment is recommended for all species. Parascaris spp. is the only ascarid species with widespread anthelmintic resistance, which allows for the study of resistance mechanisms. The purpose of this study was to establish an in vitro drug exposure protocol for adult anthelmintic-naïve Parascaris spp. and report a preliminary transcriptomic analysis in response to drug exposure. Live worms were harvested from foal necropsies and maintained in RPMI-1640 at 37 °C. Serial dilutions of oxibendazole (OBZ) and ivermectin (IVM) were prepared for in vitro drug exposure, and worm viability was monitored over time. In a second drug trial, worms were used for transcriptomic analysis. The final drug concentrations employed were OBZ at 40.1 µm (10 µg mL-1) and IVM at 1.1 µm (1 µg mL-1) for 24 and 3 h, respectively. The RNA-seq analysis revealed numerous differentially expressed genes, with some being potentially related to drug detoxification and regulatory mechanisms. This report provides a method for in vitro drug exposure and the phenotypic responses for Parascaris spp., which could be extrapolated to other ascarid parasites. Finally, it also provides preliminary transcriptomic data following drug exposure as a reference point for future studies of Parascaris spp.


Asunto(s)
Antihelmínticos/farmacología , Ascaridoidea/genética , Resistencia a Medicamentos/genética , Expresión Génica , Genes de Helminto , Transcriptoma , Animales , Ascaridoidea/efectos de los fármacos , Perfilación de la Expresión Génica , Técnicas In Vitro , RNA-Seq
7.
J Environ Radioact ; 211: 106085, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31733413

RESUMEN

The Daly River drains a large (52500 km2) and mainly undisturbed catchment in the Australian wet-dry tropics. The basin landscapes are mantled by a thick veneer of kandosol soil which has developed under varying rates of erosion, uplift, bedrock type and climate and has been identified as being suitable for agriculture. Commencement of large scale clearing and cropping since 2002 have raised concerns about the increased loss of top soil from the land clearing and cultivation activities adjacent to the Daly River. This study was undertaken to determine the modern soil loss rates which can be used to develop a sustainable soil conservation strategy for this catchment. 239Pu, released in the 1950s and 1960s by atmospheric nuclear weapons tests, is used to obtain a quantitative assessment of recent rates of soil loss. Soil cores 30-40 cm deep have been collected from fields with various land uses including peanut and hay cropping and cattle grazing. Cores taken from undisturbed and unburnt areas in open eucalypt woodland have been used as reference sites. The soil loss rates have been established by comparing the excess or deficiency of the 239Pu tracer over that of the reference sites. Since land use practices in the catchment are similar, it is likely that the measured soil loss rates are indicative of soil loss rates over the Daly Basin as well. The development of 239Pu as a soil tracer represents a viable alternative to the traditionally used 137Cs tracer. This also represents a new tool in the quantification of catchment soil loss and the adoption of appropriate soil conservation strategies for the tropical regions and regions where increasing settlement and agriculture are encroaching on catchment slopes.


Asunto(s)
Monitoreo de Radiación , Contaminantes Radiactivos del Suelo/análisis , Agricultura , Animales , Australia , Bovinos , Plutonio , Suelo
9.
Rev Sci Instrum ; 88(12): 125005, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29289169

RESUMEN

Signal attenuation limits the operating range in wireless communications and location. To solve the reduced range problem, we can use low-frequency signals in combination with magnetic sensing. We propose the use of an optically pumped magnetometer as a sensor and realize a proof-of-principle detection of binary phase shift keying (BPSK) modulated signals. We demonstrate a ranging enhancement by exploiting both the magnetometer's intrinsic sensitivity of below 1 pT/Hz1/2 and its 1 kHz operating bandwidth through the use of BPSK signals.

11.
Methods Cell Biol ; 135: 451-81, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27443940

RESUMEN

The Zebrafish Model Organism Database (ZFIN; zfin.org) serves as the central repository for genetic and genomic data produced using zebrafish (Danio rerio). Data in ZFIN are either manually curated from peer-reviewed publications or submitted directly to ZFIN from various data repositories. Data types currently supported include mutants, transgenic lines, DNA constructs, gene expression, phenotypes, antibodies, morpholinos, TALENs, CRISPRs, disease models, movies, and images. The rapidly changing methods of genomic science have increased the production of data that cannot readily be represented in standard journal publications. These large data sets require web-based presentation. As the central repository for zebrafish research data, it has become increasingly important for ZFIN to provide the zebrafish research community with support for their data sets and guidance on what is required to submit these data to ZFIN. Regardless of their volume, all data that are submitted for inclusion in ZFIN must include a minimum set of information that describes the data. The aim of this chapter is to identify data types that fit into the current ZFIN database and explain how to provide those data in the optimal format for integration. We identify the required and optional data elements, define jargon, and present tools and templates that can help with the acquisition and organization of data as they are being prepared for submission to ZFIN. This information will also appear in the ZFIN wiki, where it will be updated as our services evolve over time.


Asunto(s)
Bases de Datos Genéticas , Genómica/métodos , Pez Cebra/genética , Animales , Animales Modificados Genéticamente , Genoma/genética , Morfolinos/genética , Mutación
12.
Rev Sci Instrum ; 87(3): 034708, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27036804

RESUMEN

Cross-spectrum analysis is a commonly used technique for the detection of phase and amplitude noise of a signal in the presence of interfering uncorrelated noise. Recently, we demonstrated that the phase-inversion (anti-correlation) effect due to amplitude noise leakage can cause complete or partial collapse of the cross-spectral function. In this paper, we discuss the newly discovered effect of anti-correlated thermal noise that originates from the common-mode power divider (splitter), an essential component in a cross-spectrum noise measurement system. We studied this effect for different power splitters and discuss its influence on the measurement of thermal-noise limited oscillators. We provide theory, simulation and experimental results. In addition, we expand this study to reveal how the presence of ferrite-isolators and amplifiers at the output ports of the power splitters can affect the oscillator noise measurements. Finally, we discuss a possible solution to overcome this problem.

13.
J Vet Intern Med ; 30(2): 491-502, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26857902

RESUMEN

Equine protozoal myeloencephalitis (EPM) remains an important neurologic disease of horses. There are no pathognomonic clinical signs for the disease. Affected horses can have focal or multifocal central nervous system (CNS) disease. EPM can be difficult to diagnose antemortem. It is caused by either of 2 parasites, Sarcocystis neurona and Neospora hughesi, with much less known about N. hughesi. Although risk factors such as transport stress and breed and age correlations have been identified, biologic factors such as genetic predispositions of individual animals, and parasite-specific factors such as strain differences in virulence, remain largely undetermined. This consensus statement update presents current published knowledge of the parasite biology, host immune response, disease pathogenesis, epidemiology, and risk factors. Importantly, the statement provides recommendations for EPM diagnosis, treatment, and prevention.


Asunto(s)
Antiprotozoarios/uso terapéutico , Encefalomielitis/veterinaria , Enfermedades de los Caballos/parasitología , Guías de Práctica Clínica como Asunto , Animales , Coccidiosis/tratamiento farmacológico , Coccidiosis/veterinaria , Encefalomielitis/tratamiento farmacológico , Encefalomielitis/parasitología , Enfermedades de los Caballos/tratamiento farmacológico , Enfermedades de los Caballos/patología , Caballos , Neospora/aislamiento & purificación , Sarcocystis/aislamiento & purificación , Sarcocistosis/tratamiento farmacológico , Sarcocistosis/veterinaria
14.
J Parasitol ; 101(4): 462-7, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25811893

RESUMEN

Sarcocystis neurona is considered the major etiologic agent of equine protozoal myeloencephalitis (EPM), a neurological disease in horses. Raccoon ( Procyon lotor ) is considered the most important intermediate host in the life cycle of S. neurona in the United States; S. neurona sarcocysts do mature in raccoon muscles, and raccoons also develop clinical signs simulating EPM. The focus of this study was to determine if sarcocysts would develop in raccoons experimentally inoculated with different host-derived strains of in vitro-cultivated S. neurona merozoites. Four raccoons were inoculated with strains derived from a raccoon, a sea otter, a cat, and a horse. Raccoon tissues were fed to laboratory-raised opossums ( Didelphis virginiana ), the definitive host of S. neurona . Intestinal scraping revealed sporocysts in opossums who received muscle tissue from raccoons inoculated with the raccoon-derived or the sea otter-derived isolates. These results demonstrate that sarcocysts can mature in raccoons inoculated with in vitro-derived S. neurona merozoites. In contrast, the horse and cat-derived isolates did not produce microscopically or biologically detected sarcocysts. Immunoblot analysis revealed both antigenic and antibody differences when testing the inoculated raccoons. Immunohistochemical staining indicated differences in staining between the merozoite and sarcocyst stages. The successful infections achieved in this study indicates that the life cycle can be manipulated in the laboratory without affecting subsequent stage development, thereby allowing further purification of strains and artificial maintenance of the life cycle.


Asunto(s)
Estadios del Ciclo de Vida , Zarigüeyas/parasitología , Mapaches/parasitología , Sarcocystis/crecimiento & desarrollo , Sarcocistosis/veterinaria , Animales , Anticuerpos Antiprotozoarios/sangre , Gatos , Femenino , Caballos , Inmunohistoquímica/veterinaria , Intestinos/parasitología , Ratones , Músculos/parasitología , Oocistos/crecimiento & desarrollo , Nutrias , Embarazo , Conejos , Sarcocystis/clasificación , Sarcocystis/inmunología , Sarcocistosis/parasitología
15.
Vet Parasitol ; 209(1-2): 1-42, 2015 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-25737052

RESUMEN

Equine protozoal myeloencephalitis (EPM) is a serious disease of horses, and its management continues to be a challenge for veterinarians. The protozoan Sarcocystis neurona is most commonly associated with EPM. S. neurona has emerged as a common cause of mortality in marine mammals, especially sea otters (Enhydra lutris). EPM-like illness has also been recorded in several other mammals, including domestic dogs and cats. This paper updates S. neurona and EPM information from the last 15 years on the advances regarding life cycle, molecular biology, epidemiology, clinical signs, diagnosis, treatment and control.


Asunto(s)
Encefalomielitis/veterinaria , Infecciones Protozoarias en Animales/parasitología , Sarcocystis/clasificación , Sarcocistosis/veterinaria , Animales , Antiprotozoarios/uso terapéutico , Encefalomielitis/diagnóstico , Encefalomielitis/tratamiento farmacológico , Encefalomielitis/parasitología , Encefalomielitis/patología , Infecciones Protozoarias en Animales/diagnóstico , Infecciones Protozoarias en Animales/tratamiento farmacológico , Infecciones Protozoarias en Animales/patología , Sarcocistosis/diagnóstico , Sarcocistosis/tratamiento farmacológico , Sarcocistosis/patología
16.
Ann Biomed Eng ; 43(2): 306-13, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25274162

RESUMEN

Ideally, all chronic wounds would be prevented as they can become life threatening complications. The concept that a wound produces a 'current of injury' due to the discontinuity in the electrical field of intact skin provides the basis for the concept that electrical stimulation (ES) may provide an effective treatment for chronic wounds. The optimal stimulation waveform parameters are unknown, limiting the reliability of achieving a successful clinical therapeutic outcome. In order to gain a more thorough understanding of ES for chronic wound therapy, systematic evaluation using a valid in vivo model is required. The focus of the current paper is development of the flexible modular surface stimulation (MSS) device by our group. This device can be programed to deliver a variety of clinically relevant stimulation paradigms and is essential to facilitate systematic in vivo studies. The MSS version 2.0 for small animal use provides all components of a single-channel, programmable current-controlled ES system within a lightweight, flexible, independently-powered portable device. Benchtop testing and validation indicates that custom electronics and control algorithms support the generation of high-voltage, low duty-cycle current pulses in a power-efficient manner, extending battery life and allowing ES therapy to be delivered for up to 7 days without needing to replace or disturb the wound dressing.


Asunto(s)
Terapia por Estimulación Eléctrica/instrumentación , Cicatrización de Heridas , Suministros de Energía Eléctrica , Electrodos
17.
Rev Sci Instrum ; 85(2): 024705, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24593381

RESUMEN

Cross-spectral analysis is a mathematical tool for extracting the power spectral density of a correlated signal from two time series in the presence of uncorrelated interfering signals. We demonstrate and explain a set of amplitude and phase conditions where the detection of the desired signal using cross-spectral analysis fails partially or entirely in the presence of a second uncorrelated signal. Not understanding when and how this effect occurs can lead to dramatic under-reporting of the desired signal. Theoretical, simulated and experimental demonstrations of this effect as well as mitigating methods are presented.

18.
J Laryngol Otol ; 128(3): 274-8, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24666803

RESUMEN

OBJECTIVE: To develop a practical, efficient and predictive algorithm to manage potential or actual post-operative hypocalcaemia after complete thyroidectomy, using a single post-operative parathyroid hormone assay. METHODS: This paper reports a prospective study of 59 patients who underwent total or completion thyroidectomy over a period of 24 months. Parathyroid hormone levels were checked post-operatively on the day of surgery, and all patients were evaluated for hypocalcaemia both clinically and biochemically with serial corrected calcium measurements. RESULTS: No patient with an early post-operative parathyroid hormone level of 23 ng/l or more (i.e. approximately twice the lower limit of the normal range) developed hypocalcaemia. All the patients who initially had post-operative hypocalcaemia but had an early parathyroid hormone level of 8 ng/l or more (i.e. approximately two-thirds of the lower limit of the normal range) had complete resolution of their hypocalcaemia within three months. CONCLUSION: Early post-operative parathyroid hormone measurement can reliably predict patients at risk of post-thyroidectomy hypocalcaemia, and predict those patients expected to recover from temporary hypocalcaemia. A suggested post-operative management algorithm is presented.


Asunto(s)
Calcio/sangre , Hipocalcemia/diagnóstico , Hormona Paratiroidea/sangre , Tiroidectomía/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Biomarcadores/sangre , Diagnóstico Precoz , Femenino , Humanos , Hipocalcemia/sangre , Hipocalcemia/etiología , Hipocalcemia/terapia , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Valor Predictivo de las Pruebas , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Sensibilidad y Especificidad
20.
Community Dent Health ; 30(3): 134-7, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24151785

RESUMEN

This paper outlines a number of issues arising from a primary-care and community-based oral health education (OHE) and disease prevention pilot targeting children aged 0-7 years in County Durham and Darlington during a six month period in 2011-12. The paper highlights the key practical challenges experienced by the NHS dental practices that provided OHE predominantly in community venues and the issues arising for those involved in managing the pilot on a day to day basis. Finally, the paper suggests potential solutions and learning points for dental public health practitioners. The work described in this paper relates to three relevant dental public health competencies: strategy development and implementation; strategic leadership and collaborative working for health and oral health improvement.


Asunto(s)
Atención Dental para Niños , Odontología General , Educación en Salud Dental , Enfermedades Dentales/prevención & control , Preescolar , Inglaterra , Implementación de Plan de Salud , Disparidades en el Estado de Salud , Humanos , Lactante , Proyectos Piloto , Atención Primaria de Salud
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