Are Local Filters Blind to Provenance? Ant Seed Predation Suppresses Exotic Plants More than Natives

The question of whether species’ origins influence invasion outcomes has been a point of substantial debate in invasion ecology. Theoretically, colonization outcomes can be predicted based on how species’ traits interact with community filters, a process presumably blind to species’ origins. Yet, exotic plant introductions commonly result in monospecific plant densities not commonly seen in native assemblages, suggesting that exotic species may respond to community filters differently than natives. Here, we tested whether exotic and native species differed in their responses to a local community filter by examining how ant seed predation affected recruitment of eighteen native and exotic plant species in central Argentina. Ant seed predation proved to be an important local filter that strongly suppressed plant recruitment, but ants suppressed exotic recruitment far more than natives (89% of exotic species vs. 22% of natives). Seed size predicted ant impacts on recruitment independent of origins, with ant preference for smaller seeds resulting in smaller seeded plant species being heavily suppressed. The disproportionate effects of provenance arose because exotics had generally smaller seeds than natives. Exotics also exhibited greater emergence and earlier peak emergence than natives in the absence of ants. However, when ants had access to seeds, these potential advantages of exotics were negated due to the filtering bias against exotics. The differences in traits we observed between exotics and natives suggest that higher-order introduction filters or regional processes preselected for certain exotic traits that then interacted with the local seed predation filter. Our results suggest that the interactions between local filters and species traits can predict invasion outcomes, but understanding the role of provenance will require quantifying filtering processes at multiple hierarchical scales and evaluating interactions between filters.Fil: Pearson, Dean. University of Montana; Estados Unidos. United States Department of Agriculture; Estados UnidosFil: Icasatti, Nadia Soledad. United States Department of Agriculture; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Hierro, Jose Luis. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Bird, Benjamin B.. United States Department of Agriculture; Estados Unido

Quantum cascade lasers in biomedical infrared imaging

Technological advances, namely the integration of quantum cascade lasers (QCLs) within an infrared (IR) microscope, are enabling the development of valuable label-free biomedical-imaging tools capable of targeting and detecting salient chemical species within practical clinical timeframes

Nutritional knowledge of youth academy athletes

Background: Youth athletes are under increasing pressures to excel in their chosen sport and many turn to nutritional supplements in order to enhance sports performance. However, athletes may obtain their nutritional information via illegitimate sources such as the internet, media, and other athletes, representing miscommunication between sound scientific information and anecdotal experiences. The objective of this investigation was to examine nutrition knowledge of elite youth athletes from a non-residential regional academy of sport. Methods: A previously validated two-part nutrition knowledge questionnaire (NKQ) was administered to 101 (37 male and 64 female) non-residential regional Academy of Sport elite youth athletes at an annual training camp. Part 1 of the NKQ presented demographic questions. Part 2 presented 90 sports nutrition knowledge questions in seven knowledge subcategories (1) Nutrients; (2) Dietary reference intakes (DRI); (3) Fluids/Hydration; (4) Recovery; (5) Weight gain; (6) Weight loss; and (7) Supplements. Results: The mean NKQ score of all athletes was 43.8% (± 11.4). No gender differences observed between nutritional knowledge total scores, however female athletes recorded more ‘correct’ responses than males (p = 0.02) in the Nutrients subcategory. Majority of athletes had difficulty identifying correct DRI with this subcategory featuring the lowest percentage of ‘correct’ to ‘incorrect’ responses (27.1% ± 2.3; p = 0.02). Supplements subcategory displayed much uncertainty with significantly more ‘unsure’ than ‘incorrect’ responses (42.4% ± 20.3; p < 0.05). Conclusions: In agreement with previous research, results of the current study indicate that elite youth athletes lack fundamental nutritional knowledge, specifically related to DRI and supplementation. These data provide further support of current recommendations that Academy of Sport youth athletes may benefit from integrated nutrition education conducted by qualified nutrition professionals

FTIR imaging: a route toward automated histopathology

The focus of this study is the potential use of FTIR imaging as a tool for objective automated histopathology. The Thesis also reports the use of multivariate statistical techniques to analyse the FTIR imaging data. These include Principal Component Analysis (PCA), Hierarchical Cluster Analysis (HCA), Multivariate Curve Resolution (MCR) and Fuzzy C-Means Clustering (FCM). The development of a new PCA-FCM Clustering hybrid that can automatically detect the optimum clustering structure is also reported. Chapter 1 provides a brief introduction to the use of vibrational spectroscopy to characterise biomolecules in tissues and cells for medical diagnosis. Chapter 2 details the basic histology of a lymph node before proceeding to present imaging results gained from the analysis of both healthy and diseased lymph node tissue sections. The ability of each multivariate technique to discriminate different tissue types is discussed. In addition, the spectral features that are characteristic for each tissue type are reported. The development and application of a new PCA-FCM Clustering algorithm that can automatically determine the best clustering structure is also described in full. The results indicate that cellular abnormality provides changes to both the protein and nucleic acid vibrations. However, similar spectral profiles were identified for highly proliferating cells that were contained within reactive germinal centres of the lymph node. Chapter 3 provides a short introduction to the histology of the cervlx before presenting imaging results that were gained from the analysis of both healthy and diseased cervical tissue sections. The ability of each multivariate technique to discriminate different tissue types is discussed. In addition, the spectral features that are characteristic for each tissue type are described in detail. Novel imaging experiments upon exfoliated cervical cells are also presented. It would appear that cellular abnormality in cervical tissues and cells affects both the protein and nucleic acid features of the spectra. Glycogen and glycoprotein contributions that are prevalent in healthy tissues are also absent. Chapter 4 details sample preparation methods, the instrumentation and procedures used for data acquisition, and the subsequent data processing and multivariate techniques applied to analyse the collected spectral datasets

Exposure Keratopathy in the Intensive Care Unit: Do Not Neglect the Unseen

Exposure keratopathy (EK) is a frequently overlooked complication seen in nearly 60% of sedated or intubated intensive care unit (ICU) patients. Signs and symptoms of EK often start as mild subjective complaints of eye pain and irritation, but can progress to vision loss in the most severe cases. For many critically ill patients, the presence of sedation effectively precludes their ability to communicate clinical complaints typically associated with EK. This, combined with the potentially severe sequelae, makes EK a potentially preventable complication and a patient safety issue. Clinical management of EK can be challenging for both providers and patients due to the nature of treatment with eye drops and ointments as well as the burden and expense of associated procedural interventions. Risk factors for EK have been extensively described in the literature, and wider dissemination of this knowledge should facilitate education of physicians and nurses regarding EK prevention. The most common risk factors include lagophthalmos, chemosis, Bell’s palsy, and congenital deformities. Additionally, critically ill patients are less likely to be promptly diagnosed due to the focus of staff on life-threatening problems over ocular prophylaxis. However, the potential severity of complications associated with EK mandates that prevention remains a crucial component of the care of at-risk patients. The reader will explore the broad category of adverse medical occurrences included under the umbrella term, “errors of omission” (EOO): an error category that is most likely to culminate in EK. The most critical preventive measure is education of health care providers, although this may not be enough by itself. To this end, universal precautions against EK in combination with education may be used to help combat the relatively high incidence of this easily preventable ocular pathology

Quantum cascade laser-based mid-infrared spectrochemical imaging of tissue and biofluids

Mid-infrared spectroscopic imaging is a rapidly emerging technique in biomedical research and clinical diagnostics that takes advantage of the unique molecular fingerprint of cells, tissue and biofluids to provide a rich biochemical image without the need for staining. Spectroscopic analysis allows for the objective classification of biological material at a molecular level.1 This “label free” molecular imaging technique has been applied to histology, cytology, surgical pathology, microbiology and stem cell research, and can be used to detect subtle changes to the genome, proteome and metabolome.2,3,4 The new wealth of biochemical information made available by this technique has the distinct potential to improve cancer patient outcome through the identification of earlier stages of disease, drug resistance, new disease states and high-risk populations.4 However, despite the maturity of this science, instrumentation that provide increased sample throughput, improved image quality, a small footprint, low maintenance and require minimal spectral expertise are essential for clinical translation

FTIR imaging: a route toward automated histopathology

The focus of this study is the potential use of FTIR imaging as a tool for objective automated histopathology. The Thesis also reports the use of multivariate statistical techniques to analyse the FTIR imaging data. These include Principal Component Analysis (PCA), Hierarchical Cluster Analysis (HCA), Multivariate Curve Resolution (MCR) and Fuzzy C-Means Clustering (FCM). The development of a new PCA-FCM Clustering hybrid that can automatically detect the optimum clustering structure is also reported. Chapter 1 provides a brief introduction to the use of vibrational spectroscopy to characterise biomolecules in tissues and cells for medical diagnosis. Chapter 2 details the basic histology of a lymph node before proceeding to present imaging results gained from the analysis of both healthy and diseased lymph node tissue sections. The ability of each multivariate technique to discriminate different tissue types is discussed. In addition, the spectral features that are characteristic for each tissue type are reported. The development and application of a new PCA-FCM Clustering algorithm that can automatically determine the best clustering structure is also described in full. The results indicate that cellular abnormality provides changes to both the protein and nucleic acid vibrations. However, similar spectral profiles were identified for highly proliferating cells that were contained within reactive germinal centres of the lymph node. Chapter 3 provides a short introduction to the histology of the cervlx before presenting imaging results that were gained from the analysis of both healthy and diseased cervical tissue sections. The ability of each multivariate technique to discriminate different tissue types is discussed. In addition, the spectral features that are characteristic for each tissue type are described in detail. Novel imaging experiments upon exfoliated cervical cells are also presented. It would appear that cellular abnormality in cervical tissues and cells affects both the protein and nucleic acid features of the spectra. Glycogen and glycoprotein contributions that are prevalent in healthy tissues are also absent. Chapter 4 details sample preparation methods, the instrumentation and procedures used for data acquisition, and the subsequent data processing and multivariate techniques applied to analyse the collected spectral datasets

Landscape-Scale Patterns of Fire and Drought on the High Plains, USA

We examine 31 years (1982-2012) of temperature, precipitation and natural wildfire occurrence data for Federal and Tribal lands to determine landscape-scale patterns of drought and fire on the southern and central High Plains of the western United States. The High Plains states of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas and Wyoming have been in the midst of ongoing extreme drought, experiencing below normal precipitation and above normal temperatures for the past several years. Climate change is predicted to have multiple effects on fire regimes. Longer periods of drought conditions, coupled with hot, dry and windy weather, provide the conditions for wildfire (Ford et al., 2012), and megafires, or large-scale fires that significantly exceed those of recent decades are now occurring in grassland, shrubland and desert ecosystems (Chambers and Pellant, 2008). Our objective is to relate the frequency and size of wildfires to precipitation, temperature and latitudinal gradients to increase understanding of wildfire and drought interactions on the Great Plains in a changing climate