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1.
Mol Phylogenet Evol ; : 108144, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38972494

RESUMEN

Phylogenomic approaches have recently helped elucidate various insect relationships, but large-scale comprehensive analyses on relationships within sawflies and woodwasps are still lacking. Here, we infer the relationships and long-term biogeographic history of these hymenopteran groups using a large dataset of 354 UCE loci collected from 385 species that represent all major lineages. Early Hymenoptera started diversifying during the Early Triassic ∼249 Ma and spread all over the ancient supercontinent Pangaea. We recovered Xyeloidea as a monophyletic sister group to other Hymenoptera and Pamphilioidea as sister to Unicalcarida. Within the diverse family Tenthredinidae, our taxonomically and geographically expanded taxon sampling highlights the non-monophyly of several traditionally defined subfamilies. In addition, the recent removal of Athalia and related genera from the Tenthredinidae into the separate family Athaliidae is supported. The deep historical biogeography of the group is characterised by independent dispersals and re-colonisations between the northern (Laurasia) and southern (Gondwana) palaeocontinents. The breakup of these landmasses led to ancient vicariance in several Gondwanan lineages, while interchange across the Northern Hemisphere has continued until the Recent. The little-studied African sawfly fauna is likewise a diverse mixture of groups with varying routes of colonization. Our results reveal interesting parallels in the evolution and biogeography of early hymenopterans and other ancient insect groups.

2.
J Environ Manage ; 348: 119036, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37857223

RESUMEN

In western Canada, decades of oil-and-gas exploration have fragmented boreal landscapes with a dense network of linear forest disturbances (seismic lines). These seismic lines are implicated in the decline in wildlife populations that are adapted to function in unfragmented forest landscapes. In particular, anthropogenic disturbances have led to a decline of woodland caribou populations due to increasing predator access to core caribou habitat. Restoration of seismic lines aims to reduce the landscape fragmentation and stop the decline of caribou populations. However, planning restoration in complex landscapes can be challenging because it must account for a multitude of diverse aspects. To assist with restoration planning, we present a spatial network optimization approach that selects restoration locations in a fragmented landscape while addressing key environmental and logistical constraints. We applied the model to develop restoration scenarios in the Redrock-Prairie Creek caribou range in northwestern Alberta, Canada, which includes a combination of caribou habitat and active oil-and-gas and timber extraction areas. Our study applies network optimization at two distinct scales to address both the broad-scale restoration policy planning and project-level constraints at the level of individual forest sites. We first delineated a contiguous set of coarse-scale regions where restoration is most cost-effective and used this solution to solve a fine-scale network optimization model that addresses environmental and logistical planning constraints at the level of forest patches. Our two-tiered approach helps address the challenges of fine-scale spatial optimization of restoration activities. An additional coarse-scale optimization step finds a feasible starting solution for the fine-scale restoration problem, which serves to reduce the time to find an optimal solution. The added coarse-scale spatial constraints also make the fine-scale restoration solution align with the coarse-scale landscape features, which helps address the broad-scale restoration policies. The approach is generalizable and applicable to assist restoration planning in other regions fragmented by oil-and-gas activities.


Asunto(s)
Reno , Animales , Conservación de los Recursos Naturales , Ecosistema , Bosques , Alberta
3.
Graefes Arch Clin Exp Ophthalmol ; 260(8): 2537-2547, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35239010

RESUMEN

PURPOSE: To investigate the changes in vitreous inflammatory and angiogenic cytokine levels, primarily interleukin-(IL)-6, following intravitreal injection of the 0.19 mg fluocinolone acetonide (FAc, ILUVIEN®) implant in patients with diabetic macular edema. METHODS: A single-center phase IV study involving 12 patients' eyes with diabetic macular edema. Vitreous fluid samples were obtained prior to intravitreal injection of the fluocinolone acetonide implant and then again over a 6-month period. Vitreous samples were examined using a cytometric bead array to measure IL-6, IL-8, IP-10, MCP-1, VEGF, and CD54. PIGF and PEDF were measured using an enzyme-linked immunosorbent assay. Changes in the cytokine and chemokine expression patterns were analyzed. Clinical parameters such as BCVA and center point thickness (CPT) were also examined. RESULTS: There were mean reductions in all parameters between baseline and month 6. Significant changes (p < 0.05 versus baseline) were observed in the expression of IL-6, IP-10, MCP-1, and CD54 following the administration of fluocinolone acetonide implant. VEGF and PIGF increased at month 1 before declining at month 6, though this trend was not significant. CPT decreased rapidly between screening and the first follow-up visit, and this decrease was sustained. BCVA remained relatively stable throughout. CONCLUSION: This study demonstrated changes in vitreous inflammatory and angiogenic cytokine levels following intravitreal injection of the FAc implant in patients with diabetic macular edema. Data show that the fluocinolone acetonide implant led to rapid and sustained reductions of some inflammatory cytokines with improvement of the overall clinical picture.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Edema Macular , Quimiocina CXCL10/uso terapéutico , Citocinas , Retinopatía Diabética/complicaciones , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/tratamiento farmacológico , Implantes de Medicamentos/uso terapéutico , Femenino , Fluocinolona Acetonida , Glucocorticoides , Humanos , Interleucina-6 , Inyecciones Intravítreas , Edema Macular/diagnóstico , Edema Macular/tratamiento farmacológico , Edema Macular/etiología , Factor de Crecimiento Placentario/uso terapéutico , Factor A de Crecimiento Endotelial Vascular , Agudeza Visual
4.
BMC Med Educ ; 22(1): 599, 2022 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-35922857

RESUMEN

BACKGROUND: Microsurgery is a growing field which requires significant precision and skill. Eyesi Surgical, which is usually introduced during residency or fellowship, is an ophthalmologic microsurgery simulator which allows users to practice abstract microsurgical skills and more specialized skills. The purpose of this study was to assess the inclusion of microsurgical simulation training during medical school. METHODS: Seventy-nine German medical students in their 10th semester of education completed up to two days of training on the simulator during their ophthalmology clerkship. They received an objective numeric score based on simulator performance and completed pre and post training subjective questionnaires. RESULTS: There was no relationship found between students' Eyesi Surgical performance scores and their specialty interests (p = .8). The majority of students (73.4%) rated their microsurgical skills to be higher after simulator training than before training (p < 0.001). 92.4% of students found the Eyesi Surgical to be a useful component of the ophthalmology clerkship. Objective scores from Navigation Training Level 1 showed that students achieved better results in the criteria categories of Completing Objects and Tissue Treatment than in the categories of Instrument and Microscope Handling. The mean Total Score was 25.7 (± 17.5) out of a possible 100 points. CONCLUSION: The inclusion of surgical simulation in the ophthalmology clerkship led to increased confidence in the microsurgical skills of medical students. Offering surgical simulation training prior to residency can help to expose students to surgical fields, identify those that have particular talent and aptitude for surgery, and assist them in deciding which specialty to pursue.


Asunto(s)
Internado y Residencia , Oftalmología , Entrenamiento Simulado , Estudiantes de Medicina , Competencia Clínica , Simulación por Computador , Alemania , Humanos , Microcirugia , Oftalmología/educación , Estudios Prospectivos , Entrenamiento Simulado/métodos
5.
Ophthalmic Res ; 61(3): 159-167, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29852494

RESUMEN

PURPOSE: Surgical or diagnostic procedures are often accompanied by a short-term increase in intraocular pressure (IOP). A short-term increase in IOP can occur during refractive procedures, vitreoretinal surgery, transillumination, photocoagulation, or cryocoagulation. A porcine eye model was chosen (n = 89) to compile comparable study data and to de termine correlations between the force induced and the resulting intraocular pressure while excluding the effect of surgeons. METHODS: The IOP was measured in the anterior chamber. IOP changes were induced by applying an external force and measured when using a cannula, trocar, and cryocoagulation (n = 32), and correlations between force and resulting IOP were assessed (n = 57). RESULTS: A correlation was noted between the force induced and the IOP increase, which showed a linear dependency. The insertion of a 29-G cannula caused a mean ΔIOP value of 49.1 ± 2.9 mm Hg and an external force of 0.76 N, and that of a 23-G trocar 344.4 ± 5.9 mm Hg and 6.09 N, respectively. The rise in IOP during a simulated cryocoagulation reached values between 57.3 ± 14.8 mm Hg (cryoprobe tip diameter: 0.9 mm) and 130.3 ± 2.9 mm Hg (cryoprobe tip diameter: 7.0 mm). CONCLUSION: The values of the forces applied can be converted into the resulting IOP based on the specific action. Surgical or diagnostic procedures should, therefore, be evaluated with regard to preexisting pathologies, such as glaucoma.


Asunto(s)
Cámara Anterior/fisiopatología , Presión Intraocular/fisiología , Presión , Cirugía Vitreorretiniana , Animales , Cateterismo/métodos , Criocirugía , Modelos Animales , Procedimientos Quirúrgicos Oftalmológicos , Porcinos , Tonometría Ocular
6.
Graefes Arch Clin Exp Ophthalmol ; 255(11): 2185-2198, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28779364

RESUMEN

PURPOSE: For diaphanoscopy or transscleral laser applications, the transmission of the sclera is an essential property. The study aimed to determine the pressure dependent transmission of human sclera from anterior to posterior. METHODS: Pressure dependent transmission measurements were performed by a pressure inducing setup at the range of 60-2058 kPa. The transmissions were measured within spectral range of 350-1100 nm. Specimens of human sclera were taken from corneo-scleral transplants. Those compounds were obtained at pars plicata residual sclera tissue. For an anterior to posterior examination of transmission, samples were taken from halved eye globes, which were formerly fixed in formalin. RESULTS: The pressure dependent transmission increased with rising load at all measured wavelengths for human sclera samples. The highest increase was observed for short wavelengths. With rising pressure, the increase of transmission aimed for a steady state. This behavior was fitted by a limited growing function. With an inducing burden of 2058 kPa, the steady state was already reached and exhibited an increase in transmission factor of 4.1 at 400 nm and 1.8 at 1000 nm. The anterior to posterior measurements of human sclera fixed in formalin were not corresponding to the results of the other human samples. For the porcine samples, the transmission increased from anterior to the equator of the eye globe. Further posterior the transmission decreased and rose again to N. opticus. With rising pressure, the transmission increased at all wavelengths and all locations. Posterior from the equator, with higher pressure the transmission became superior compared to anterior. CONCLUSIONS: The results of human sclera fixed in formalin could be related to formalin-induced cross-linking between the collagen fibers. Because of doubt about the physiological behavior of formalin-fixed samples, formalin-free porcine postmortem eye globes were also probed having a very similar thickness and histological structure as human sclera, so the results could be set in relation to human probes. These results can now be used to create an eye-map to determine maximum possible retina irradiation or illumination durations for transscleral applications in eye surgery.


Asunto(s)
Segmento Anterior del Ojo/fisiología , Segmento Posterior del Ojo/fisiología , Esclerótica/fisiología , Animales , Fenómenos Biomecánicos , Humanos , Luz , Presión , Porcinos , Transiluminación/métodos
7.
J Environ Manage ; 193: 188-200, 2017 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-28226258

RESUMEN

Assessing risks of uncertain but potentially damaging events, such as environmental disturbances, disease outbreaks and pest invasions, is a key analytical step that informs subsequent decisions about how to respond to these events. We present a continuous risk measure that can be used to assess and prioritize environmental risks from uncertain data in a geographical domain. The metric is influenced by both the expected magnitude of risk and its uncertainty. We demonstrate the approach by assessing risks of human-mediated spread of Asian longhorned beetle (ALB, Anoplophora glabripennis) in Greater Toronto (Ontario, Canada). Information about the human-mediated spread of ALB through this urban environment to individual geographical locations is uncertain, so each location was characterized by a set of probabilistic rates of spread, derived in this case using a network model. We represented the sets of spread rates for the locations by their cumulative distribution functions (CDFs) and then, using the first-order stochastic dominance rule, found ordered non-dominant subsets of these CDFs, which we then used to define different classes of risk across the geographical domain, from high to low. Because each non-dominant subset was estimated with respect to all elements of the distribution, the uncertainty in the underlying data was factored into the delineation of the risk classes; essentially, fewer non-dominant subsets can be defined in portions of the full set where information is sparse. We then depicted each non-dominant subset as a point cloud, where points represented the CDF values of each subset element at specific sampling intervals. For each subset, we then defined a hypervolume bounded by the outermost convex frontier of that point cloud. This resulted in a collection of hypervolumes for every non-dominant subset that together serve as a continuous measure of risk, which may be more practically useful than averaging metrics or ordinal rank measures. Overall, the approach offers a rigorous depiction of risk in a geographical domain when the underlying estimates of risk for individual locations are represented by sets or distributions of uncertain estimates. Our hypervolume-based approach can be used to compare assessments made with different datasets and assumptions.


Asunto(s)
Modelos Teóricos , Medición de Riesgo , Animales , Ambiente , Geografía , Humanos , Incertidumbre
8.
Exp Eye Res ; 146: 107-117, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26769219

RESUMEN

Neovascular age-related macular degeneration (nAMD) has been described as a predominantly inflammatory and proangiogenic retino-choroidal disease. Vitreous humor (VH) is the adjacent and accessible compartment which, due to the vicinity to the retina, might best represent changes of protein-based mediators of nAMD. The aim of this clinical-experimental study was to analyze the nAMD associated VH proteome of previously untreated patients whilst taking different groups of nAMD into account, based on their clinical presentation (clinical diagnosis groups). Electrophoresis coupled online to mass spectrometry (CE-MS) as well as liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) were used to analyze VH of 108 nAMD patients and 24 controls with idiopathic floaters. A total of 101 different proteins with at least two unique peptides could be identified. Using a stringent statistical analysis with implementation of the closed test principle, we were able to identify four proteins that may be involved in the pathophysiology of nAMD: Clusterin, opticin, pigment epithelium-derived factor and prostaglandin-H2 d-isomerase. Using independent samples, ROC-Area under the curve was determined proving the validity of the results: Clusterin 0.747, opticin 0.656, pigment epithelium-derived factor 0.514, prostaglandin-H2 d-isomerase 0.712. In addition, validation through ELISA measurements was performed. The identified proteins may serve as potential biomarkers or even targets of therapy for nAMD.


Asunto(s)
Neovascularización Coroidal/metabolismo , Clusterina/metabolismo , Oxidorreductasas Intramoleculares/metabolismo , Lipocalinas/metabolismo , Degeneración Macular/metabolismo , Proteómica/métodos , Cuerpo Vítreo/metabolismo , Anciano , Biomarcadores/metabolismo , Neovascularización Coroidal/complicaciones , Neovascularización Coroidal/patología , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Humanos , Degeneración Macular/etiología , Degeneración Macular/patología , Masculino , Espectrometría de Masas , Persona de Mediana Edad , Estudios Retrospectivos , Cuerpo Vítreo/patología
9.
Graefes Arch Clin Exp Ophthalmol ; 253(9): 1529-35, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25957763

RESUMEN

PURPOSE: Conventional chandelier-endoilluminators used for pars-plana vitrectomy consist of a light-emitting tip attached to an optical fibre. The tip requires introduction into the ocular space through an incision. To achieve complete illumination of the intraocular space, the introduction of more than just one tip is sometimes necessary. An extraocular vitreoretinal LED-endoilluminator discussed in this paper represents a new approach to illuminate the intraocular space. The light source is integrated into a speculum and firmly apposed to the sclera. This approach offers the advantage of effectively illuminating the interior of the eye even though the procedure is non-invasive. Furthermore, this approach significantly reduces the risk of damage to the retina by phototoxic effects. METHODS: A round white LED was used as a light source. By integrating the light source into a speculum, the LED was firmly held against the sclera. Thus, the ocular space was illuminated transsclerally. As a result, indirect uniform illumination of the complete intraocular space was achieved. The prototype was developed considering the relevant international standards. Porcine eyes were used because their properties are similar to those of human eyes. RESULTS: Porcine eyes could be acceptably illuminated with the selected LED. The LED-endoilluminator conforms with international standards for endoillumination. Thus, possible photochemical and thermal risks are considered and reduced to a minimum. CONCLUSIONS: A novel LED-endoilluminator which can be attached to a speculum was developed. The system does not need any connection to an external light source and, consequently, also avoids usage of an optical fibre. Regular and uniform illumination of the intraocular space was achieved by transmitted and scattered visible irradiation, avoiding an incision. The duration of potential light exposure, compared to existing illumination systems, can be significantly increased. This is also true when the illuminator is not directly placed over the pars-plana and the distance to the retina is reduced. Only a part of the light reaches the retina and the fraction of short wavelength becomes very small. Increased safety of the system results from now being able to increase the exposure time and reduce phototoxic stress to the retina.


Asunto(s)
Luz , Iluminación/instrumentación , Instrumentos Quirúrgicos , Cirugía Vitreorretiniana/instrumentación , Animales , Traumatismos Experimentales por Radiación/prevención & control , Retina/efectos de la radiación , Porcinos
12.
Ophthalmol Ther ; 13(6): 1601-1617, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38615132

RESUMEN

INTRODUCTION: Simulation training is an important component of medical education. In former studies, diagnostic simulation training for direct and indirect funduscopy was already proven to be an effective training method. In this prospective controlled trial, we investigated the effect of simulator-based fundus biomicroscopy training. METHODS: After completing a 1-week ophthalmology clerkship, medical students at Saarland University Medical Center (n = 30) were block-randomized into two groups: The traditional group received supervised training examining the fundus of classmates using a slit lamp; the simulator group was trained using the Slit Lamp Simulator. All participants had to pass an Objective Structured Clinical Examination (OSCE); two masked ophthalmological faculty trainers graded the students' skills when examining patient's fundus using a slit lamp. A subjective assessment form and post-assessment surveys were obtained. Data were described using median (interquartile range [IQR]). RESULTS: Twenty-five students (n = 14 in the simulator group, n = 11 in the traditional group) (n = 11) were eligible for statistical analysis. Interrater reliability was verified as significant for the overall score as well as for all subtasks (≤ 0.002) except subtask 1 (p = 0.12). The overall performance of medical students in the fundus biomicroscopy OSCE was statistically ranked significantly higher in the simulator group (27.0 [5.25]/28.0 [3.0] vs. 20.0 [7.5]/16.0 [10.0]) by both observers with an interrater reliability of IRR < 0.001 and a significance level of p = 0.003 for observer 1 and p < 0.001 for observer 2. For all subtasks, the scores given to students trained using the simulator were consistently higher than those given to students trained traditionally. The students' post-assessment forms confirmed these results. Students could learn the practical backgrounds of fundus biomicroscopy (p = 0.04), the identification (p < 0.001), and localization (p < 0.001) of pathologies significantly better with the simulator. CONCLUSIONS: Traditional supervised methods are well complemented by simulation training. Our data indicate that the simulator helps with first patient contacts and enhances students' capacity to examine the fundus biomicroscopically.

13.
Med Microbiol Immunol ; 202(1): 37-47, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22669631

RESUMEN

Although several host factors have been identified to influence the course of HCMV infection, it still remains unclear why in AIDS patients without highly active antiretroviral therapy human cytomegalovirus (HCMV) retinitis is one of the most common opportunistic infections, whereas in other immunosuppressed individuals it has a low incidence. It was suggested that HCMV glycoprotein B strains may be suitable as marker for virulence and HCMV retinitis. Moreover, UL144 ORF, a member of the TNF-α receptor superfamily, may play a crucial role in innate defences and adaptive immune response of HCMV infection. Furthermore, sequence analyses of HCMV genes UL128, UL130, and UL131A as major determinants of virus entry and replication in epithelial and other cell types were performed. To evaluate the association of sequence variability of depicted viral genes with HCMV retinitis and in vitro growth properties in retinal pigment epithelial cells (RPE) and human foreskin fibroblasts (HFF), we compared 14 HCMV isolates obtained from vitreous fluid and urine of AIDS patients with clinically proven HCMV retinitis. Isolates were analyzed by PCR cycle sequencing and phylogenetic analysis. In addition, sequences of HCMV strains AF1, U8, U11, VR1814, and its cell culture adapted derivates were included. Sequence analysis of gB yielded three genetic subtypes (gB type 1 (5 isolates), gB type 2 (12 isolates), and gB type 3 (5 Isolates)), whereas sequence analysis of UL144 showed a greater diversity (7 isolates type 1A, 2 isolates type 1C, 7 isolates type 2, and 3 isolates type 3). In contrast, the UL128, UL130, and UL131A genes of all low-passage isolates were highly conserved and showed no preferential clustering. Moreover, in HFF and RPE cells, all of our HCMV isolates replicated efficiently independently of their genetic subtype. In conclusion, beside a possible link between the gB subtype 2 and HCMV retinitis, our study found no direct evidence for a connection between UL144/UL128/UL130/UL131A genotypes and the incidence of HCMV retinitis in AIDS patients.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Retinitis por Citomegalovirus/virología , Citomegalovirus/clasificación , Citomegalovirus/genética , Polimorfismo Genético , Adulto , Línea Celular , Niño , Análisis por Conglomerados , Citomegalovirus/aislamiento & purificación , ADN Viral/genética , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Filogenia , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Orina/virología , Proteínas Virales/genética , Cuerpo Vítreo/virología
14.
Risk Anal ; 33(9): 1694-709, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23339716

RESUMEN

Invasive species risk maps provide broad guidance on where to allocate resources for pest monitoring and regulation, but they often present individual risk components (such as climatic suitability, host abundance, or introduction potential) as independent entities. These independent risk components are integrated using various multicriteria analysis techniques that typically require prior knowledge of the risk components' importance. Such information is often nonexistent for many invasive pests. This study proposes a new approach for building integrated risk maps using the principle of a multiattribute efficient frontier and analyzing the partial order of elements of a risk map as distributed in multidimensional criteria space. The integrated risks are estimated as subsequent multiattribute frontiers in dimensions of individual risk criteria. We demonstrate the approach with the example of Agrilus biguttatus Fabricius, a high-risk pest that may threaten North American oak forests in the near future. Drawing on U.S. and Canadian data, we compare the performance of the multiattribute ranking against a multicriteria linear weighted averaging technique in the presence of uncertainties, using the concept of robustness from info-gap decision theory. The results show major geographic hotspots where the consideration of tradeoffs between multiple risk components changes integrated risk rankings. Both methods delineate similar geographical regions of high and low risks. Overall, aggregation based on a delineation of multiattribute efficient frontiers can be a useful tool to prioritize risks for anticipated invasive pests, which usually have an extremely poor prior knowledge base.


Asunto(s)
Monitoreo del Ambiente/métodos , Especies Introducidas , Medición de Riesgo/métodos , Algoritmos , Animales , Canadá , Escarabajos , Sistemas de Información Geográfica , Geografía , Modelos Estadísticos , Árboles , Incertidumbre , Estados Unidos
15.
J Environ Manage ; 129: 173-82, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-23927853

RESUMEN

Long-distance introductions of alien species are often driven by socioeconomic factors, such that conventional "biological" invasion models may not be capable of estimating spread fully and reliably. In this study, we demonstrate a new technique for assessing and reconstructing human-mediated pathways of alien forest species entries to major settlements in Canada via commercial road transportation and domestic trade. We undertook our analysis in three steps. First, we used existing data on movement of commodities associated with bark- and wood-boring forest pests to build a probabilistic model of how the organisms may be moved from one location to another through a transportation network. We then used this model to generate multiple sets of predictions of species arrival rates at every location in the transportation network, and to identify the locations with the highest likelihood of new incursions. Finally, we evaluated the sensitivity of the species arrival rates to uncertainty in key model assumptions by testing the impact of additive and multiplicative errors (by respectively adding a uniform random variate or symmetric variation bounds to the arrival rate values) on the probabilities of pest transmission from one location to another, as well as the impact of the removal of one or more nodes and all connecting links to other nodes from the underlying transportation network. Overall, the identification of potential pest arrival hotspots is moderately robust to uncertainties in key modeling assumptions. Large urban areas and major border crossings that have the highest predicted species arrival rates have the lowest sensitivities to uncertainty in the pest transmission potential and to random changes in the structure of the transportation network. The roadside survey data appears to be sufficient to delineate major hubs and hotspots where pests are likely to arrive from other locations in the network via commercial truck transport. However, "pass-through" locations with few incoming and outgoing routes can be identified with lower precision. The arrival rates of alien forest pests appear to be highly sensitive to additive errors. Surprisingly, the impact of random changes in the structure of the transportation network was relatively low.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Control de Insectos/métodos , Insectos/fisiología , Especies Introducidas , Animales , Canadá , Ecosistema , Modelos Biológicos , Probabilidad , Transportes , Estados Unidos
16.
Sci Rep ; 13(1): 3666, 2023 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-36871063

RESUMEN

Forests across much of the United States are becoming denser. Trees growing in denser stands experience more competition for essential resources, which can make them more vulnerable to disturbances. Forest density can be expressed in terms of basal area, a metric that has been used to assess vulnerability of some forests to damage by certain insects or pathogens. A raster map of total tree basal area (TBA) for the conterminous United States was compared with annual (2000-2019) survey maps of forest damage due to insects and pathogens. Across each of four regions, median TBA was significantly higher within forest areas defoliated or killed by insects or pathogens than in areas without recorded damage. Therefore, TBA may serve as a regional-scale indicator of forest health and a first filter for identifying areas that merit finer-scale analysis of forest conditions.


Asunto(s)
Bosques , Insectos , Animales , Registros , Árboles
17.
Ophthalmol Ther ; 12(4): 2171-2186, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37294522

RESUMEN

INTRODUCTION: Simulation training has an important role in medical education. In ophthalmology, simulation-based training has been shown to be significantly effective for surgical and diagnostic training in direct and indirect ophthalmoscopy. In this study, we analysed the effects of simulator-based slit lamp training. METHODS: In this prospective controlled trial, medical students in their eighth semester at Saarland University Medical Center (n = 24) who had attended a 1-week ophthalmological internship were randomized into two groups: The traditional group (n = 12) was examined directly after the 1-week internship; the simulator group (n = 12) was trained with the slit lamp simulator before passing an objective structured clinical examination (OSCE). A masked ophthalmological faculty trainer assessed the students' slit lamp skills (maximum total score 42 points [pts]): preparation (5 pts), clinical examination (9.5 pts), assessment of findings (9.5 pts), diagnosis (3 pts), commentary on the examination approach (8 pts), measurement of structures (2 pts) and recognition of five diagnoses (5 pts). All students completed post-assessment surveys. Examination grades and survey responses were compared between the groups. RESULTS: The overall performance of the slit lamp OSCE was significantly better (p < 0.001) in the simulator group than in the traditional group (29.75 [7.88] vs. 17.00 [4.75]) with significantly higher scores for the preparation and assessment of slit lamp controls (5.0 [0.0] vs. 3.0 [3.5]; p = 0.008) and localization of relevant structures (6.75 [3.13] vs. 4.0 [1.5]; p = 0.008). Consistently higher scores, but not significant, were assigned for the description of structures found (4.5 [3.38] vs. 3.25 [2.13]; p = 0.09) and the correct diagnosis (3.0 [0.0] vs. 3.0 [0.0]; p = 0.48). Surveys reflected the students' subjectively perceived knowledge gain during the simulator training for slit lamp illumination techniques (p = 0.002), recognition (p < 0.001), and assessment of the correct localization of pathologies (p < 0.001). CONCLUSION: Slit lamp examination is an important diagnostic method in ophthalmology. Simulator-based training improved students' examination techniques for localizing anatomical structures and pathological lesions. The transfer of theoretical knowledge into practice can be achieved in a stress-free atmosphere.

18.
Br J Ophthalmol ; 107(10): 1502-1508, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-35840291

RESUMEN

BACKGROUND: The ILUVIEN Registry Safety Study was a multicentre, open-label, non-randomised, observational, phase 4 study designed to assess the safety and effectiveness of the fluocinolone acetonide (FAc) implant in all indications in real-world practices in Europe. METHODS: The study included data collected prospectively and retrospectively. Patients receiving FAc implants between 2013 and 2017 were included and monitored until the last patient reached ≥3 years of follow-up. Mean intraocular pressure (IOP) data over the course of the study, along with IOP events, use of IOP-lowering therapy, mean change in visual acuity (VA) and information on supplemental therapy use were analysed post-FAc implantation. RESULTS: Six hundred and ninety-five eyes from 556 patients, with a mean±SD follow-up of 1150.5±357.36 days, were treated with a FAc implant. 96.7% of eyes had chronic diabetic macular oedema (cDMO). IOP lowering was achieved in 34.5% of eyes using topical agents and 4.3% by surgery. Seventy-three eyes (64.6% of 113 phakic) required cataract surgery during follow-up. Mean VA increased from a baseline of 52.2 letters to 57.1 letters at month 36, with improvement observed up to month 48. Supplementary therapies were given in 43.7% of eyes. When classified by length of cDMO less than or greater than the median duration those with a shorter history experienced greater VA gains than those with a longer history. CONCLUSION: This study confirms the favourable, long-term benefit-to-risk profile of the FAc implant in eyes with cDMO, with an additional benefit in patients when this therapy is administered earlier.


Asunto(s)
Retinopatía Diabética , Edema Macular , Humanos , Fluocinolona Acetonida , Glucocorticoides/uso terapéutico , Edema Macular/tratamiento farmacológico , Estudios Retrospectivos , Implantes de Medicamentos , Inyecciones Intravítreas , Iris
19.
J Econ Entomol ; 105(2): 438-50, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22606814

RESUMEN

Recreational travel is a recognized vector for the spread of invasive species in North America. However, there has been little quantitative analysis of the risks posed by such travel and the associated transport of firewood. In this study, we analyzed the risk of forest insect spread with firewood and estimated related dispersal parameters for application in geographically explicit invasion models. Our primary data source was the U.S. National Recreation Reservation Service database, which records camper reservations at > 2,500 locations nationwide. For > 7 million individual reservations made between 2004 and 2009 (including visits from Canada), we calculated the distance between visitor home address and campground location. We constructed an empirical dispersal kernel (i.e., the probability distribution of the travel distances) from these "origin-destination" data, and then fitted the data with various theoretical distributions. We found the data to be strongly leptokurtic (fat-tailed) and fairly well fit by the unbounded Johnson and lognormal distributions. Most campers ( approximately 53%) traveled <100 km, but approximately 10% traveled > 500 km (and as far as 5,500 km). Additionally, we examined the impact of geographic region, specific destinations (major national parks), and specific origin locations (major cities) on the shape of the dispersal kernel, and found that mixture distributions (i.e., theoretical distribution functions composed of multiple univariate distributions) may fit better in some circumstances. Although only a limited amount of all transported firewood is likely to be infested by forest insects, this still represents a considerable increase in dispersal potential beyond the insects' natural spread capabilities.


Asunto(s)
Migración Animal , Insectos/fisiología , Especies Introducidas , Animales , Acampada , Modelos Biológicos , Dinámica Poblacional , Especificidad de la Especie , Viaje , Estados Unidos , Madera
20.
Clin Ophthalmol ; 16: 3711-3720, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36389636

RESUMEN

Introduction: To investigate the safety and efficacy of the Vitesse hypersonic vitrectomy device for retinal reattachment surgery in proliferative vitreoretinopathy (PVR) or proliferative diabetic vitreoretinopathy (PDVR) cases. The Vitesse device utilizes hypersonic technology to liquefy instead of cutting the vitreous, providing an alternative to the traditional pneumatic guillotine cutter. Material and Methods: A prospective, one-armed, non-comparative, open-label study was performed. Sixteen patients with a diagnosis of PVR or PDVR that required retinal reattachment surgery were included. Severity of disease was classified using the Retina Society 1983 classification and Kroll Classification from 2007. Patient data was collected preoperatively, 2 days postoperatively, 1 month postoperatively, and 3 months postoperatively. Efficacy of hypersonic vitrectomy was evaluated, both subjectively using a questionnaire and objectively by means of Supplementary Video documentation, device settings, and data collection of the patients' medical history. Results: In all 16 cases, retinal reattachment surgery could be performed with Vitesse without conversion to a guillotine cutter. The vitreous could be separated from the detached retina completely with no iatrogenic tissue damage. Vitreous traction was documented in one case. In 6 cases, shaving of the vitreous base was performed after early fluid-air exchange with hypersonic vitrectomy without any complications. No adverse events suspected to be related to hypersonic vitrectomy were documented in the follow-up visits. Conclusion: The Vitesse has potential advantages including reduced vacuum volumes with limited amount of turbulence and avoidance vitreoretinal traction. Liquefaction directly in front of the probe entrance allows for continuous unrestricted fluid flow. These factors of hypersonic technology allow to carry out retinal reattachment surgery in PVR or PDVR cases successfully.

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