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1.
J Cancer Surviv ; 15(1): 54-65, 2021 02.
Article in English | MEDLINE | ID: mdl-32613442

ABSTRACT

PURPOSE: The purpose of this research was to describe the challenges young adult childhood cancer survivors (ACCS) experience of living with an unknown fertility status. METHODS: In this qualitative study, we analyzed data from in-depth interviews with 25 ACCS (15 females, 10 males) using content-driven inductive thematic analysis and constant comparative techniques. RESULTS: Three themes provide insight into ACCS' experiences of living with an uncertain fertility status. (1) The marked psychological burden, which included fear, worry, anxiety, and sadness, was ubiquitous. (2) Romantic relationships were negatively affected and entailed fear of disappointing one's partner, the difficulty of discussing fertility issues, and shying away from romantic relationships. (3) Communication challenges with healthcare providers were apparent across the cancer trajectory, made worse by provider knowledge gaps and dismissal of fertility concerns. (4) Well-known gender stereotypes about pregnancy and childrearing were replicated, while the emotional and life impacts that uncertain fertility could exert on males were minimized. CONCLUSION: This study provides beginning insights into the experiences of young ACCS as they navigate an unknown fertility status and highlights existing gaps in fertility-related healthcare services. IMPLICATIONS FOR CANCER SURVIVORS: Uncertain fertility has implications for survivors' wellbeing that remain poorly addressed by the existing structure of cancer survivor and fertility services. Assessing and addressing the fertility-related needs of ACCS will continue to be a vital component of patient-centered care in the future, and research to develop comprehensive support, resources, and processes of care are vital to meet this priority need.


Subject(s)
Cancer Survivors , Infertility , Neoplasms , Child , Female , Fertility , Humans , Male , Survivors , Young Adult
2.
Water Res ; 169: 115222, 2020 Feb 01.
Article in English | MEDLINE | ID: mdl-31675609

ABSTRACT

Benthic cyanobacteria are a nuisance because they produce highly potent toxins and taste and odour compounds. Despite this, benthic cyanobacteria remain far less studied than their planktonic counterparts. For example, little is known about their growth or the seasonality of their secondary metabolite production. Moreover, sampling and monitoring techniques commonly used for the survey of planktonic species are not necessarily applicable to benthic forms. This study aimed to develop and validate a new sampling device for the routine monitoring of benthic mats. Molecular monitoring techniques were established and validated on environmental samples collected in a South Australian reservoir (SA-L2). A total of eight qPCR assays were applied to samples in order to track seasonal variations in cyanobacteria concentrations and associated secondary metabolite production. Next Generation Sequencing was utilised to conduct a microbial community composition analysis and to select the most appropriate substrate material for the sampling of benthic cyanobacteria. The concentration of the secondary metabolites geosmin and 2-methyl-isoborneol were quantified using High-Performance Liquid Chromatography, and concentrations of key nutrients (N, P) were quantified in water samples. The sampling device designed proved efficient and easy to use in the field. The qPCR assay designed for the amplification of the cyanobacterial MIB synthase had a high efficiency with a minimum limit of quantification of 4 cell-equivalents per reaction and identified a potential source of MIB in SA-L2 Reservoir. The peak season for benthic growth and secondary metabolite production was observed in spring. Proportionally, 35% of the variability in water geosmin concentrations can be explained by benthic actinobacterial and cyanobacterial activity, showing that freshwater benthic mats represent a significant source of taste and odour compounds.


Subject(s)
Cyanobacteria , Australia , Fresh Water , Odorants , Taste
3.
J Cancer Surviv ; 12(3): 277-290, 2018 06.
Article in English | MEDLINE | ID: mdl-29222704

ABSTRACT

PURPOSE: Risk-stratified life-long follow-up care is recommended for adult childhood cancer survivors (CCS) to ensure appropriate prevention, screening, and management of late effects. The identification of barriers to long-term follow-up (LTFU), particularly in varying healthcare service contexts, is essential to develop and refine services that are responsive to survivor needs. We aimed to explore CCS and healthcare professionals (HCP) perspectives of healthcare system factors that function as barriers to LTFU in British Columbia, Canada. METHODS: We analyzed data from 43 in-depth interviews, 30 with CCS and 13 with HCP, using qualitative thematic analysis and constant comparative methods. RESULTS: Barriers to accessible, comprehensive, quality LTFU were associated with the following: (1) the difficult and abrupt transition from pediatric to adult health services, (2) inconvenient and under-resourced health services, (3) shifting patient-HCP relationships, (4) family doctor inadequate experience with late effects management, and (5) overdue and insufficient late effects communication with CCS. CONCLUSIONS: Structural, informational, and interpersonal/relational healthcare system factors often prevent CCS from initially accessing LTFU after discharge from pediatric oncology programs as well as adversely affecting engagement in ongoing screening, surveillance, and management of late effects. IMPLICATIONS FOR CANCER SURVIVORS: Understanding the issues faced by adult CCS will provide insight necessary to developing patient-centered healthcare solutions that are key to accessible, acceptable, appropriate, and effective healthcare.


Subject(s)
Aftercare , Cancer Survivors , Delivery of Health Care , Neoplasms/epidemiology , Neoplasms/therapy , Adult , Aftercare/organization & administration , Aftercare/standards , Age of Onset , British Columbia/epidemiology , Cancer Survivors/statistics & numerical data , Child , Communication Barriers , Delivery of Health Care/organization & administration , Delivery of Health Care/standards , Disease Progression , Female , Follow-Up Studies , Health Services Accessibility/organization & administration , Health Services Accessibility/standards , Humans , Male , Medical Oncology/methods , Medical Oncology/organization & administration , Medical Oncology/standards , Neoplasms/rehabilitation , Professional-Patient Relations , Qualitative Research , Transition to Adult Care/organization & administration , Transition to Adult Care/standards
4.
Am J Trop Med Hyg ; 96(3): 749-757, 2017 03.
Article in English | MEDLINE | ID: mdl-28138052

ABSTRACT

Many neglected tropical zoonotic pathogens are maintained by introduced mammals, and on islands the most common introduced species are rodents, cats, and dogs. Management of introduced mammals, including control or eradication of feral populations, which is frequently done for ecological restoration, could also reduce or eliminate the pathogens these animals carry. Understanding the burden of these zoonotic diseases is crucial for quantifying the potential public health benefits of introduced mammal management. However, epidemiological data are only available from a small subset of islands where these introduced mammals co-occur with people. We examined socioeconomic and climatic variables as predictors for disease burdens of angiostrongyliasis, leptospirosis, toxoplasmosis, toxocariasis, and rabies from 57 islands or island countries. We found strong correlates of disease burden for leptospirosis, Toxoplasma gondii infection, angiostrongyliasis, and toxocariasis with more than 50% of the variance explained, and an average of 57% (range = 32-95%) predictive accuracy on out-of-sample data. We used these relationships to provide estimates of leptospirosis incidence and T. gondii seroprevalence infection on islands where nonnative rodents and cats are present. These predicted estimates of disease burden could be used in an initial assessment of whether the costs of managing introduced mammal reservoirs might be less than the costs of perpetual treatment of these diseases on islands.


Subject(s)
Leptospirosis/epidemiology , Rabies/epidemiology , Strongylida Infections/epidemiology , Toxocariasis/epidemiology , Toxoplasmosis, Animal/epidemiology , Zoonoses/epidemiology , Animals , Animals, Wild/parasitology , Animals, Wild/virology , Humans , Incidence , Islands , Leptospirosis/veterinary , Mammals/parasitology , Mammals/virology , Public Health , Rabies/veterinary , Seroepidemiologic Studies , Socioeconomic Factors , Strongylida Infections/veterinary , Zoonoses/parasitology , Zoonoses/virology
5.
Sci Total Environ ; 565: 1192-1200, 2016 Sep 15.
Article in English | MEDLINE | ID: mdl-27265732

ABSTRACT

In conventional water treatment processes, where the coagulation and flocculation steps are designed to remove particles from drinking water, cyanobacteria are also concentrated into the resultant sludge. As a consequence, cyanobacteria-laden sludge can act as a reservoir for metabolites such as taste and odour compounds and cyanotoxins. This can pose a significant risk to water quality where supernatant from the sludge treatment facility is returned to the inlet to the plant. In this study the complex processes that can take place in a sludge treatment lagoon were investigated. It was shown that cyanobacteria can proliferate in the conditions manifest in a sludge treatment lagoon, and that cyanobacteria can survive and produce metabolites for at least 10days in sludge. The major processes of metabolite release and degradation are very dependent on the physical, chemical and biological environment in the sludge treatment facility and it was not possible to accurately model the net effect. For the first time evidence is provided to suggest that there is a greater risk associated with recycling sludge supernatant than can be estimated from the raw water quality, as metabolite concentrations increased by up to 500% over several days after coagulation, attributed to increased metabolite production and/or cell proliferation in the sludge.


Subject(s)
Cyanobacteria/physiology , Drinking Water/chemistry , Drinking Water/microbiology , Water Pollutants, Chemical/analysis , Water Purification , Flocculation , Recycling , South Australia , Water Supply
6.
PLoS One ; 11(5): e0155003, 2016.
Article in English | MEDLINE | ID: mdl-27171169

ABSTRACT

There is increasing evidence to suggest that the sinus microbiome plays a role in the pathogenesis of chronic rhinosinusitis (CRS). However, the concentration of these microorganisms within the sinuses is still unknown. We show that flow cytometry can be used to enumerate bacteria and virus-like particles (VLPs) in sinus flush samples of CRS patients. This was achieved through trialling 5 sample preparation techniques for flow cytometry. We found high concentrations of bacteria and VLPs in these samples. Untreated samples produced the highest average bacterial and VLP counts with 3.3 ± 0.74 x 10(7) bacteria ml(-1) and 2.4 ± 1.23 x 10(9) VLP ml(-1) of sinus flush (n = 9). These counts were significantly higher than most of the treated samples (p < 0.05). Results showed 10(3) and 10(4) times inter-patient variation for bacteria and VLP concentrations. This wide variation suggests that diagnosis and treatment need to be personalised and that utilising flow cytometry is useful and efficient for this. This study is the first to enumerate bacterial and VLP populations in the maxillary sinus of CRS patients. The relevance of enumeration is that with increasing antimicrobial resistance, antibiotics are becoming less effective at treating bacterial infections of the sinuses, so alternative therapies are needed. Phage therapy has been proposed as one such alternative, but for dosing, the abundance of bacteria is required. Knowledge of whether phages are normally present in the sinuses will assist in gauging the safety of applying phage therapy to sinuses. Our finding, that large numbers of VLP are frequently present in sinuses, indicates that phage therapy may represent a minimally disruptive intervention towards the nasal microbiome. We propose that flow cytometry can be used as a tool to assess microbial biomass dynamics in sinuses and other anatomical locations where infection can cause disease.


Subject(s)
Bacteria/growth & development , Flow Cytometry/methods , Paranasal Sinuses/microbiology , Rhinitis/microbiology , Rhinitis/virology , Sinusitis/microbiology , Sinusitis/virology , Virion/physiology , Body Fluids , Chronic Disease , Fluorescence , Humans , Paranasal Sinuses/virology
7.
PLoS One ; 11(1): e0146984, 2016.
Article in English | MEDLINE | ID: mdl-26785114

ABSTRACT

Microbial interactions are important for ecosystem function, but occur at the microscale and so are difficult to observe. Previous studies in marine systems have shown significant shifts in microbial community abundance and composition over scales of micrometres to centimetres. This study investigates the microscale abundance distributions of virus-like particles (VLPs) and prokaryotes in the lower reaches of a river to determine the extent to which microscale microbial patchiness exists in freshwater systems. Here we report local hotspots surrounded by gradients that reach a maximum 80 and 107 fold change in abundance over 0.9 cm for prokaryotic and VLP subpopulations. Changes in prokaryotic and VLP hotspots were tightly coupled. There were no gradients at tens of centimetres across the boundary layers, which is consistent with strong mixing and turbulence-driven aggregation found in river systems. Quantification of the patchiness shows a marked asymmetry with patches 10 times greater than background common, but depletions being rare or absent in most samples. This consistent asymmetry suggests that coldspots depleted by grazing and lysis are rapidly mixed to background concentrations, while the prevalence of hotspots indicates persistence against disruption. The hotspot to coldspot relative abundance may be useful for understanding microbial river dynamics. The patchiness indicates that the mean- field approach of bulk phase sampling misses the microbially relevant community variation and may underestimate the concentrations of these important microbial groups.


Subject(s)
Archaea/growth & development , Bacteria/growth & development , Viruses/growth & development , Water Microbiology , Algorithms , Australia , Fresh Water/microbiology , Rivers/microbiology , Spatial Analysis
8.
ACG Case Rep J ; 2(3): 181-3, 2015 Apr.
Article in English | MEDLINE | ID: mdl-26157957

ABSTRACT

Primary malignant tumors of the heart, specifically cardiac sarcomas, are rare and mainly diagnosed at autopsy. Acute Budd-Chiari syndrome is a recognized cause of acute liver failure and has been associated with several rare cardiac tumors: atrial myxoma, caval rhabdomyosarcoma, and primary cardiac adenocarcinoma. We present the first case of a fatal, highly differentiated cardiac synovial sarcoma that presented as acute liver failure from Budd-Chiari syndrome.

9.
Mol Phylogenet Evol ; 83: 72-85, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25462995

ABSTRACT

Manta and devil rays are an iconic group of globally distributed pelagic filter feeders, yet their evolutionary history remains enigmatic. We employed next generation sequencing of mitogenomes for nine of the 11 recognized species and two outgroups; as well as additional Sanger sequencing of two mitochondrial and two nuclear genes in an extended taxon sampling set. Analysis of the mitogenome coding regions in a Maximum Likelihood and Bayesian framework provided a well-resolved phylogeny. The deepest divergences distinguished three clades with high support, one containing Manta birostris, Manta alfredi, Mobula tarapacana, Mobula japanica and Mobula mobular; one containing Mobula kuhlii, Mobula eregoodootenkee and Mobula thurstoni; and one containing Mobula munkiana, Mobula hypostoma and Mobula rochebrunei. Mobula remains paraphyletic with the inclusion of Manta, a result that is in agreement with previous studies based on molecular and morphological data. A fossil-calibrated Bayesian random local clock analysis suggests that mobulids diverged from Rhinoptera around 30 Mya. Subsequent divergences are characterized by long internodes followed by short bursts of speciation extending from an initial episode of divergence in the Early and Middle Miocene (19-17 Mya) to a second episode during the Pliocene and Pleistocene (3.6 Mya - recent). Estimates of divergence dates overlap significantly with periods of global warming, during which upwelling intensity - and related high primary productivity in upwelling regions - decreased markedly. These periods are hypothesized to have led to fragmentation and isolation of feeding regions leading to possible regional extinctions, as well as the promotion of allopatric speciation. The closely shared evolutionary history of mobulids in combination with ongoing threats from fisheries and climate change effects on upwelling and food supply, reinforces the case for greater protection of this charismatic family of pelagic filter feeders.


Subject(s)
Biological Evolution , Phylogeny , Skates, Fish/classification , Animals , Bayes Theorem , Cell Nucleus/genetics , Fossils , Genome, Mitochondrial , High-Throughput Nucleotide Sequencing , Likelihood Functions , Models, Genetic , Sequence Alignment , Sequence Analysis, DNA
10.
Respir Med ; 108(11): 1626-32, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25225149

ABSTRACT

RATIONALE: The relationship between pulmonary artery size with underlying pulmonary hypertension and mortality remains to be determined in COPD. We sought to evaluate the relationships in a cohort of patients with advanced COPD. METHODS: A retrospective study of advanced COPD patients evaluated between 1998 and 2012 was conducted at a tertiary care center. Patients with chest computed tomography images and right heart catheterizations formed the study cohort. The diameters of the pulmonary artery and ascending aorta were measured by independent observers and compared to pulmonary artery pressures. Intermediate-term mortality was evaluated for the 24-month period subsequent to the respective studies. Cox proportional hazards model was used to determine independent effects of variables on survival. RESULTS: There were 65 subjects identified, of whom 38 (58%) had pulmonary hypertension. Patients with and without pulmonary hypertension had mean pulmonary artery diameters of 34.4 mm and 29.1 mm, respectively (p = 0.0003). The mean PA:A ratio for those with and without pulmonary hypertension was 1.05 and 0.87, respectively (p = 0.0003). The PA:A ratio was an independent predictor of mortality with a reduced survival in those with a PA:A >1 (p = 0.008). CONCLUSIONS: The PA:A ratio is associated with underlying pulmonary hypertension in patients with COPD and is an independent predictor of mortality. This readily available measurement may be a valuable non-invasive screening tool for underlying pulmonary hypertension in COPD patients and appears to impart important independent prognostic information.


Subject(s)
Hypertension, Pulmonary/etiology , Hypertension, Pulmonary/pathology , Pulmonary Artery/pathology , Pulmonary Disease, Chronic Obstructive/complications , Aorta/pathology , Arterial Pressure/physiology , Female , Forced Expiratory Volume/physiology , Humans , Hypertension, Pulmonary/diagnostic imaging , Hypertension, Pulmonary/physiopathology , Kaplan-Meier Estimate , Male , Middle Aged , Prognosis , Pulmonary Artery/diagnostic imaging , Pulmonary Artery/physiopathology , Pulmonary Disease, Chronic Obstructive/diagnostic imaging , Pulmonary Disease, Chronic Obstructive/physiopathology , Retrospective Studies , Risk Factors , Tomography, X-Ray Computed
11.
Clin Chest Med ; 35(3): 451-6, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25156761

ABSTRACT

The sleep state is associated with significant changes in respiratory physiology, including ventilatory responses to hypoxia and hypercapnia, upper airway and intercostal muscle tone, and tidal volume and minute ventilation. These changes are further magnified in certain disease states, such as chronic obstructive pulmonary disease, restrictive respiratory disorders, neuromuscular conditions, and cardiac diseases. This article discusses the regulation of breathing during sleep in health and associated comorbid conditions.


Subject(s)
Respiration Disorders/physiopathology , Respiratory Physiological Phenomena , Sleep/physiology , Airway Resistance/physiology , Heart Diseases/physiopathology , Humans , Hypercapnia/physiopathology , Hypoxia/physiopathology , Pulmonary Disease, Chronic Obstructive/physiopathology , Respiratory Mechanics/physiology , Respiratory Muscles/physiology , Respiratory Muscles/physiopathology , Sleep Apnea Syndromes/physiopathology
12.
PLoS One ; 9(7): e102805, 2014.
Article in English | MEDLINE | ID: mdl-25057797

ABSTRACT

The marine sediment-water interface is an important location for microbially controlled nutrient and gas exchange processes. While microbial distributions on the sediment side of the interface are well established in many locations, the distributions of microbes on the water side of the interface are less well known. Here, we measured that distribution for marine virio- and bacterioplankton with a new two-dimensional technique. Our results revealed higher heterogeneity in sediment-water interface biomass distributions than previously reported with a greater than 45- and 2500-fold change cm(-1) found within bacterial and viral subpopulations compared to previous maxima of 1.5- and 1.4-fold cm(-1) in bacteria and viruses in the same environments. The 45-fold and 2500-fold changes were due to patches of elevated and patches of reduced viral and bacterial abundance. The bacterial and viral hotspots were found over single and multiple sample points and the two groups often coincided whilst the coldspots only occurred over single sample points and the bacterial and viral abundances showed no correlation. The total mean abundances of viruses strongly correlated with bacteria (r = 0.90, p<0.0001, n = 12) for all three microplates (n = 1350). Spatial autocorrelation analysis via Moran's I and Geary's C revealed non-random distributions in bacterial subpopulations and random distributions in viral subpopulations. The variable distributions of viral and bacterial abundance over centimetre-scale distances suggest that competition and the likelihood of viral infection are higher in the small volumes important for individual cell encounters than bulk measurements indicate. We conclude that large scale measurements are not an accurate measurement of the conditions under which microbial dynamics exist. The high variability we report indicates that few microbes experience the 'average' concentrations that are frequently measured.


Subject(s)
Bacteria/growth & development , Geologic Sediments/microbiology , Plankton/growth & development , Rivers/microbiology , Viruses/growth & development , Water Microbiology , Aquatic Organisms , Australia , Spatial Analysis , Temperature
13.
Conserv Biol ; 28(5): 1282-90, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24661307

ABSTRACT

Seabirds are the most threatened group of marine animals; 29% of species are at some risk of extinction. Significant threats to seabirds occur on islands where they breed, but in many cases, effective island conservation can mitigate these threats. To guide island-based seabird conservation actions, we identified all islands with extant or extirpated populations of the 98 globally threatened seabird species, as recognized on the International Union for Conservation of Nature Red List, and quantified the presence of threatening invasive species, protected areas, and human populations. We matched these results with island attributes to highlight feasible island conservation opportunities. We identified 1362 threatened breeding seabird populations on 968 islands. On 803 (83%) of these islands, we identified threatening invasive species (20%), incomplete protected area coverage (23%), or both (40%). Most islands with threatened seabirds are amenable to island-wide conservation action because they are small (57% were <1 km(2) ), uninhabited (74%), and occur in high- or middle-income countries (96%). Collectively these attributes make islands with threatened seabirds a rare opportunity for effective conservation at scale.


Subject(s)
Animal Distribution , Birds/physiology , Conservation of Natural Resources , Endangered Species , Animals , Biodiversity , Introduced Species , Islands
14.
Environ Microbiol Rep ; 5(5): 725-30, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24115623

ABSTRACT

Knowledge about viral diversity and abundance in deep groundwater reserves is limited. We found that the viral community inhabiting a deep confined aquifer in South Australia was more similar to reclaimed water communities than to the viral communities in the overlying unconfined aquifer community. This similarity was driven by high relative occurrence of the single-stranded DNA viral groups Circoviridae, Geminiviridae and Microviridae, which include many known plant and animal pathogens. These groups were present in a 1500-year-old water situated 80 m below the surface, which suggests the potential for long-term survival and spread of potentially pathogenic viruses in deep, confined groundwater. Obtaining a broader understanding of potentially pathogenic viral communities within aquifers is particularly important given the ability of viruses to spread within groundwater ecosystems.


Subject(s)
Disease Reservoirs/virology , Groundwater/virology , Viruses/isolation & purification , Biodiversity , Ecosystem , Molecular Sequence Data , Phylogeny , Viruses/classification , Viruses/genetics
15.
Environ Microbiol Rep ; 4(5): 548-55, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23760900

ABSTRACT

Different oceanographic provinces host discrete microbial assemblages that are adapted to local physicochemical conditions. We sequenced and compared the metagenomes of two microbial communities inhabiting adjacent water masses in the Tasman Sea, where the recent strengthening of the East Australian Current (EAC) has altered the ecology of coastal environments. Despite the comparable latitude of the samples, significant phylogenetic differences were apparent, including shifts in the relative frequency of matches to Cyanobacteria, Crenarchaeota and Euryarchaeota. Fine-scale variability in the structure of SAR11, Prochlorococcus and Synechococcus populations, with more matches to 'warm-water' ecotypes observed in the EAC, indicates the EAC may drive an intrusion of tropical microbes into temperate regions of the Tasman Sea. Furthermore, significant shifts in the relative importance of 17 metabolic categories indicate that the EAC prokaryotic community has different physiological properties than surrounding waters.

16.
Environ Microbiol ; 14(1): 240-53, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22004107

ABSTRACT

A metagenomic analysis of two aquifer systems located under a dairy farming region was performed to examine to what extent the composition and function of microbial communities varies between confined and surface-influenced unconfined groundwater ecosystems. A fundamental shift in taxa was seen with an overrepresentation of Rhodospirillales, Rhodocyclales, Chlorobia and Circovirus in the unconfined aquifer, while Deltaproteobacteria and Clostridiales were overrepresented in the confined aquifer. A relative overrepresentation of metabolic processes including antibiotic resistance (ß-lactamase genes), lactose and glucose utilization and DNA replication were observed in the unconfined aquifer, while flagella production, phosphate metabolism and starch uptake pathways were all overrepresented in the confined aquifer. These differences were likely driven by differences in the nutrient status and extent of exposure to contaminants of the two groundwater systems. However, when compared with freshwater, ocean, sediment and animal gut metagenomes, the unconfined and confined aquifers were taxonomically and metabolically more similar to each other than to any other environment. This suggests that intrinsic features of groundwater ecosystems, including low oxygen levels and a lack of sunlight, have provided specific niches for evolution to create unique microbial communities. Obtaining a broader understanding of the structure and function of microbial communities inhabiting different groundwater systems is particularly important given the increased need for managing groundwater reserves of potable water.


Subject(s)
Bacteria/genetics , Ecosystem , Groundwater/microbiology , Metagenome , Bacteria/metabolism , DNA, Bacterial/genetics , Dairying , Environmental Monitoring
17.
PLoS One ; 6(9): e25173, 2011.
Article in English | MEDLINE | ID: mdl-21966446

ABSTRACT

Environmental parameters drive phenotypic and genotypic frequency variations in microbial communities and thus control the extent and structure of microbial diversity. We tested the extent to which microbial community composition changes are controlled by shifting physiochemical properties within a hypersaline lagoon. We sequenced four sediment metagenomes from the Coorong, South Australia from samples which varied in salinity by 99 Practical Salinity Units (PSU), an order of magnitude in ammonia concentration and two orders of magnitude in microbial abundance. Despite the marked divergence in environmental parameters observed between samples, hierarchical clustering of taxonomic and metabolic profiles of these metagenomes showed striking similarity between the samples (>89%). Comparison of these profiles to those derived from a wide variety of publically available datasets demonstrated that the Coorong sediment metagenomes were similar to other sediment, soil, biofilm and microbial mat samples regardless of salinity (>85% similarity). Overall, clustering of solid substrate and water metagenomes into discrete similarity groups based on functional potential indicated that the dichotomy between water and solid matrices is a fundamental determinant of community microbial metabolism that is not masked by salinity, nutrient concentration or microbial abundance.


Subject(s)
Metagenomics/methods , Seawater/microbiology , Ecosystem , Metagenome , Sequence Analysis, DNA , Soil Microbiology
18.
J Exp Biol ; 211(Pt 23): 3712-9, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19011211

ABSTRACT

Lunge feeding in rorqual whales is a drag-based feeding mechanism that is thought to entail a high energetic cost and consequently limit the maximum dive time of these extraordinarily large predators. Although the kinematics of lunge feeding in fin whales supports this hypothesis, it is unclear whether respiratory compensation occurs as a consequence of lunge-feeding activity. We used high-resolution digital tags on foraging humpback whales (Megaptera novaengliae) to determine the number of lunges executed per dive as well as respiratory frequency between dives. Data from two whales are reported, which together performed 58 foraging dives and 451 lunges. During one study, we tracked one tagged whale for approximately 2 h and examined the spatial distribution of prey using a digital echosounder. These data were integrated with the dive profile to reveal that lunges are directed toward the upper boundary of dense krill aggregations. Foraging dives were characterized by a gliding descent, up to 15 lunges at depth, and an ascent powered by steady swimming. Longer dives were required to perform more lunges at depth and these extended apneas were followed by an increase in the number of breaths taken after a dive. Maximum dive durations during foraging were approximately half of those previously reported for singing (i.e. non-feeding) humpback whales. At the highest lunge frequencies (10 to 15 lunges per dive), respiratory rate was at least threefold higher than that of singing humpback whales that underwent a similar degree of apnea. These data suggest that the high energetic cost associated with lunge feeding in blue and fin whales also occurs in intermediate sized rorquals.


Subject(s)
Biomechanical Phenomena , Diving , Feeding Behavior , Humpback Whale/physiology , Respiration , Animals , Time Factors
19.
Resuscitation ; 65(3): 309-14, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15919567

ABSTRACT

OBJECTIVES: A method for determining the number of automatic external defibrillators (AEDs) required for a 3-min response at mass gatherings has been described previously. Our study sought to modify the method, replicate it, then validate the results. METHODS: Emergency medical technicians (EMTs) were timed walking defined courses in a football stadium. Velocities were obtained for a horizontal distance and ascending/descending upper and lower decks. This was replicated in a basketball arena. To validate, actual response times were compared to predicted times for predetermined distances in each venue. Predicted response times were calculated using the second standard deviation velocities as the most pessimistic. Numbers of AEDs needed were calculated using predicted response times for each venue's longest distance. RESULTS: Average velocities in m/s (football) were horizontal 1.7, lower deck 1.6 ascending and 1.4 descending, upper deck 1.0 ascending and 1.1 descending. Average velocities (basketball) were horizontal 1.7, lower deck 1.2 ascending and descending, upper deck 0.9 ascending and descending. In the validation phase, every EMT completed the four predetermined courses within the predicted intervals. Predicted response times were 363 s for the longest football stadium distance, and 187 s for the basketball arena. For a 3-min (180 s) response, the number of AEDs required can be calculated. CONCLUSION: This method was easily replicated and appears to be useful for determining the number of AEDs at mass gatherings. The number of AEDs needed for any desired response interval can be calculated using the predicted response time for the longest distance within an arena.


Subject(s)
Advanced Cardiac Life Support/instrumentation , Defibrillators/statistics & numerical data , Electric Countershock/instrumentation , Needs Assessment , Time and Motion Studies , Adult , Female , Heart Arrest/therapy , Humans , Male , Middle Aged , Models, Theoretical , Public Facilities , Sports , Time Factors
20.
Acad Emerg Med ; 12(4): 296-301, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15805319

ABSTRACT

BACKGROUND: Death notification is a common, difficult, and emotionally laden communication for emergency physicians. Teaching emergency medicine residents the skills for success in this communication is an important focus for educators. To accomplish this task, educators need practical, proven teaching and assessment tools focused on death notification skills. OBJECTIVES: To test the hypothesis that a teaching module, based on the mnemonic "GRIEV_ING," could improve resident confidence, competency, and communication skills when delivering a death notification. METHODS: The GRIEV_ING intervention consisted of a two-hour educational session composed of small-group, role-play, and didactic experiences. The authors used a pre-post-retention repeated-measures design to test their hypothesis immediately following and three months after training. For each assessment cycle, three quantitative measures were collected: self-confidence, relationship-communication, and competency. Relationship-communication and competency scores were collected during simulated survivor encounters. RESULTS: Complete data for 20 residents were obtained. Significant improvements were noted in resident confidence scores at the pre-post (F = 16.7, p <0.0001) and pre-retention (F = 14.0, p = 0.001) comparisons. Likewise, significant improvements were noted in resident competence scores at the pre-post (F = 4.7, p = 0.04) and pre-retention (F = 8.8, p = 0.008) comparisons. Resident relationship-communication scores were uniformly high, and there was no significant change in this score across study intervals. CONCLUSIONS: This study demonstrates that a defined educational intervention focused on the GRIEV_ING mnemonic can improve physician confidence and competence in death notification.


Subject(s)
Communication , Internship and Residency , Interpersonal Relations , Adult , Emergency Medicine/education , Humans , Professional-Family Relations , Teaching/methods
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