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1.
Water Res ; 235: 119799, 2023 May 15.
Article in English | MEDLINE | ID: mdl-36965294

ABSTRACT

Microbial-driven nitrogen removal is a crucial step in modern full-scale wastewater treatment plants (WWTPs), and the complexity of nitrogen transformation is integral to the various wastewater treatment processes. A full understanding of the overall nitrogen cycling networks in WWTPs is therefore a prerequisite for the further enhancement and optimization of wastewater treatment processes. In this study, metagenomics and metatranscriptomics were used to elucidate the microbial nitrogen removal processes in an ammonium-enriched full-scale WWTP, which was configured as an anaerobic-anoxic-anaerobic-oxic system for efficient nitrogen removal (99.63%) on a duck breeding farm. A typical simultaneous nitrification-anammox-denitrification (SNAD) process was established in each tank of this WWTP. Ammonia was oxidized by ammonia-oxidizing bacteria (AOB), archaea (AOA), and nitrite-oxidizing bacteria (NOB), and the produced nitrite and nitrate were further reduced to dinitrogen gas (N2) by anammox and denitrifying bacteria. Visible red anammox biofilms were formed successfully on the sponge carriers submerged in the anoxic tank, and the nitrogen removal rate by anammox reaction was 4.85 times higher than that by denitrification based on 15N isotope labeling and analysis. This supports the significant accumulation of anammox bacteria on the carriers responsible for efficient nitrogen removal. Two distinct anammox bacteria, named "Ca. Brocadia sp. PF01" and "Ca. Jettenia sp. PF02", were identified from the biofilm in this investigation. By recovering their genomic features and their metabolic capabilities, our results indicate that the highly active core anammox process found in PF01, suggests extending its niche within the plant. With the possible contribution of the dissimilatory nitrate reduction to ammonium (DNRA) reaction, enriching PF02 within the biofilm may also be warranted. Collectively, this study highlights the effective design strategies of a full-scale WWTP with enrichment of anammox bacteria on the carrier materials for nitrogen removal and therefore the biochemical reaction mechanisms of the contributing members.


Subject(s)
Ammonium Compounds , Water Purification , Ammonia/metabolism , Denitrification , Wastewater , Nitrites/metabolism , Nitrates/metabolism , Anaerobic Ammonia Oxidation , Nitrogen/metabolism , Anaerobiosis , Oxidation-Reduction , Bioreactors/microbiology , Ammonium Compounds/metabolism , Bacteria/genetics , Bacteria/metabolism , Water Purification/methods
2.
Intern Med J ; 53(2): 275-279, 2023 02.
Article in English | MEDLINE | ID: mdl-36585764

ABSTRACT

Within the first 4 months of the Western Australian COVID-19 immunisation programme, 49 suspected anaphylaxis cases were reported to the vaccine safety surveillance system. Twelve reports met Brighton Collaboration case definition, corresponding to rates of 15.9 and 17.7 per million doses of Vaxzevria and Comirnaty administered respectively.


Subject(s)
Anaphylaxis , COVID-19 Vaccines , COVID-19 , Humans , Adverse Drug Reaction Reporting Systems , Anaphylaxis/etiology , Australia/epidemiology , BNT162 Vaccine , ChAdOx1 nCoV-19 , COVID-19/etiology , COVID-19 Vaccines/adverse effects , Vaccination/adverse effects , Western Australia
3.
Opt Express ; 30(10): 17230-17242, 2022 May 09.
Article in English | MEDLINE | ID: mdl-36221550

ABSTRACT

The flexible membranes used in MEMS tunable VCSELs are so small and light that thermally induced vibrations can impact laser performance. We measure the thermal vibration spectrum of such a membrane showing peaks at the spatial vibration mode resonant frequencies of the membrane/plate. These vibrations result in a theoretical floor to the linewidth of the VCSEL. Frequency domain LiDAR and optical coherence tomography systems can get around this thermal linewidth limit with adequate clock measurement and processing. Essentially an OCT/LiDAR sweep with a concomitantly measured clock is a feed-forward linewidth reduction scheme. This can be achieved because the membrane resonances are relatively low frequency. LiDAR ranging out to 9 meters has been demonstrated with a resolution of 13 µm, close to the transform limit for the 70 nm sampling range.

4.
Ecotoxicology ; 30(7): 1279-1280, 2021 09.
Article in English | MEDLINE | ID: mdl-34142304
6.
J Paediatr Child Health ; 57(9): 1397-1401, 2021 Sep.
Article in English | MEDLINE | ID: mdl-33847439

ABSTRACT

AIM: To describe the epidemiology of invasive Salmonella disease in children in the Northern Territory, Australia. METHODS: Design: A retrospective review of invasive salmonellosis cases identified by pathology records and the Northern Territory Notifiable Disease Surveillance System. Case definitions: Those aged 18 years or under, with Salmonella cultured from a usually sterile site, collected in the Northern Territory between 1 July 2005 and 30 June 2015. OUTCOME MEASURES: The primary outcome measure was the annual incidence rate of invasive salmonellosis, comparing rates between Indigenous and non-Indigenous children. RESULTS: There were 86 cases of invasive Salmonella infection in children over the 10-year period; an annual incidence of 14.1 per 100 000 population, in those aged less than 18 years. Gastrointestinal Salmonella notifications were similar between Indigenous and non-Indigenous children. In children aged less than 15 years, the rate of invasive salmonellosis was higher in Indigenous children compared to non-Indigenous children (23.4 per 100 000 compared with 11.6 per 100 000); rate ratio 2.0 (95% confidence interval 1.3-3.3, P = 0.002). Indigenous children with invasive salmonellosis had a median hospital stay of 8 days, which was compared to 5 days for non-Indigenous children (P = 0.015). The highest incidence rate of invasive salmonellosis occurred in Indigenous patients less than 12 months of age (138 per 100 000). CONCLUSION: The Northern Territory of Australia has high rates of invasive salmonellosis in children. Indigenous and non-Indigenous children experience similar rates of Salmonella gastroenteritis but Indigenous children experience higher rates of invasive salmonellosis.


Subject(s)
Salmonella Infections , Age Distribution , Child , Humans , Incidence , Infant , Northern Territory/epidemiology , Retrospective Studies , Salmonella Infections/epidemiology
7.
Biomed Opt Express ; 10(3): 1207-1222, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30891340

ABSTRACT

Tethered capsule endomicroscopy (TCE) is an emerging screening technology that comprehensively obtains microstructural OCT images of the gastrointestinal (GI) tract in unsedated patients. To advance clinical adoption of this imaging technique, it will be important to validate TCE images with co-localized histology, the current diagnostic gold standard. One method for co-localizing OCT images with histology is image-targeted laser marking, which has previously been implemented using a driveshaft-based, balloon OCT catheter, deployed during endoscopy. In this paper, we present a TCE device that scans and targets the imaging beam using a low-cost stepper motor that is integrated inside the capsule. In combination with a 4-laser-diode, high power 1430/1450 nm marking laser system (800 mW on the sample and 1s pulse duration), this technology generated clearly visible marks, with a spatial targeting accuracy of better than 0.5 mm. A laser safety study was done on swine esophagus ex vivo, showing that these exposure parameters did not alter the submucosa, with a large, 4-5x safety margin. The technology was demonstrated in living human subjects and shown to be effective for co-localizing OCT TCE images to biopsies obtained during subsequent endoscopy.

8.
Physiol Rep ; 6(11): e13740, 2018 06.
Article in English | MEDLINE | ID: mdl-29890035

ABSTRACT

There are hardly any published data on the characteristics of muscle nerve sympathetic discharges occurring in parallel with the somatic motoneurone discharges in the same nerves. Here, we take advantage of the naturally occurring respiratory activity in recordings of efferent discharges from branches of the intercostal and abdominal nerves in anesthetized cats to make this comparison. The occurrence of efferent spikes with amplitudes below that for alpha motoneurones were analyzed for cardiac modulation, using cross-correlation between the times of the R-wave of the ECG and the efferent spikes. The modulation was observed in nearly all recordings, and for all categories of nerves. It was strongest for the smallest amplitude spikes or spike-like waveforms, which were deduced to comprise postsynaptic sympathetic discharges. New observations were: (1) that the cardiac modulation of these discharges was modest compared to most previous reports for muscle nerves; (2) that the amplitudes of the sympathetic discharges compared to those of the somatic spikes were strongly positively correlated to nerve diameter, such that, for the larger nerves, their amplitudes overlapped considerably with those of gamma motoneurone spikes. This could be explained by random summation of high rates of unit sympathetic spikes. We suggest that under some experimental circumstances this overlap could lead to considerable ambiguity in the identity of the discharges in efferent neurograms.


Subject(s)
Action Potentials , Intercostal Nerves/physiology , Motor Neurons/physiology , Sympathetic Nervous System , Animals , Cats , Electrocardiography , Female , Male , Motor Neurons, Gamma/physiology , Respiration
9.
Sci Rep ; 7(1): 8182, 2017 08 15.
Article in English | MEDLINE | ID: mdl-28811631

ABSTRACT

Neutrophil breach of the mucosal surface is a common pathological consequence of infection. We present an advanced co-culture model to explore neutrophil transepithelial migration utilizing airway mucosal barriers differentiated from primary human airway basal cells and examined by advanced imaging. Human airway basal cells were differentiated and cultured at air-liquid interface (ALI) on the underside of 3 µm pore-sized transwells, compatible with the study of transmigrating neutrophils. Inverted ALIs exhibit beating cilia and mucus production, consistent with conventional ALIs, as visualized by micro-optical coherence tomography (µOCT). µOCT is a recently developed imaging modality with the capacity for real time two- and three-dimensional analysis of cellular events in marked detail, including neutrophil transmigratory dynamics. Further, the newly devised and imaged primary co-culture model recapitulates key molecular mechanisms that underlie bacteria-induced neutrophil transepithelial migration previously characterized using cell line-based models. Neutrophils respond to imposed chemotactic gradients, and migrate in response to Pseudomonas aeruginosa infection of primary ALI barriers through a hepoxilin A3-directed mechanism. This primary cell-based co-culture system combined with µOCT imaging offers significant opportunity to probe, in great detail, micro-anatomical and mechanistic features of bacteria-induced neutrophil transepithelial migration and other important immunological and physiological processes at the mucosal surface.


Subject(s)
Cell Culture Techniques , Coculture Techniques , Inflammation/metabolism , Inflammation/pathology , Respiratory Mucosa/metabolism , Respiratory Mucosa/pathology , 8,11,14-Eicosatrienoic Acid/analogs & derivatives , 8,11,14-Eicosatrienoic Acid/metabolism , Cell Line , Cell Movement/immunology , Cell Polarity , Chemotaxis, Leukocyte/immunology , Epithelial Cells/metabolism , Epithelial Cells/pathology , Fluorescent Antibody Technique , Humans , Inflammation/immunology , Inflammation/microbiology , Neutrophil Infiltration/immunology , Neutrophils/immunology , Neutrophils/metabolism , Neutrophils/pathology , Respiratory Mucosa/immunology , Respiratory Mucosa/microbiology
10.
Biomed Opt Express ; 7(7): 2494-505, 2016 Jul 01.
Article in English | MEDLINE | ID: mdl-27446685

ABSTRACT

We have designed and fabricated a 4 mm diameter rigid endoscopic probe to obtain high resolution micro-optical coherence tomography (µOCT) images from the tracheal epithelium of living swine. Our common-path fiber-optic probe used gradient-index focusing optics, a selectively coated prism reflector to implement a circular-obscuration apodization for depth-of-focus enhancement, and a common-path reference arm and an ultra-broadbrand supercontinuum laser to achieve high axial resolution. Benchtop characterization demonstrated lateral and axial resolutions of 3.4 µm and 1.7 µm, respectively (in tissue). Mechanical standoff rails flanking the imaging window allowed the epithelial surface to be maintained in focus without disrupting mucus flow. During in vivo imaging, relative motion was mitigated by inflating an airway balloon to hold the standoff rails on the epithelium. Software implemented image stabilization was also implemented during post-processing. The resulting image sequences yielded co-registered quantitative outputs of airway surface liquid and periciliary liquid layer thicknesses, ciliary beat frequency, and mucociliary transport rate, metrics that directly indicate airway epithelial function that have dominated in vitro research in diseases such as cystic fibrosis, but have not been available in vivo.

11.
Int J Environ Res Public Health ; 12(4): 4076-100, 2015 Apr 13.
Article in English | MEDLINE | ID: mdl-25872019

ABSTRACT

Racial and ethnic minority communities, including American Indian and Alaska Natives, have been disproportionately impacted by environmental pollution and contamination. This includes siting and location of point sources of pollution, legacies of contamination of drinking and recreational water, and mining, military and agricultural impacts. As a result, both quantity and quality of culturally important subsistence resources are diminished, contributing to poor nutrition and obesity, and overall reductions in quality of life and life expectancy. Climate change is adding to these impacts on Native American communities, variably causing drought, increased flooding and forced relocation affecting tribal water resources, traditional foods, forests and forest resources, and tribal health. This article will highlight several extramural research projects supported by the United States Environmental Protection Agency (USEPA) Science to Achieve Results (STAR) tribal environmental research grants as a mechanism to address the environmental health inequities and disparities faced by tribal communities. The tribal research portfolio has focused on addressing tribal environmental health risks through community based participatory research. Specifically, the STAR research program was developed under the premise that tribal populations may be at an increased risk for environmentally-induced diseases as a result of unique subsistence and traditional practices of the tribes and Alaska Native villages, community activities, occupations and customs, and/or environmental releases that significantly and disproportionately impact tribal lands. Through a series of case studies, this article will demonstrate how grantees-tribal community leaders and members and academic collaborators-have been addressing these complex environmental concerns by developing capacity, expertise and tools through community-engaged research.


Subject(s)
Community-Based Participatory Research , Environmental Health , Health Status Disparities , Indians, North American , Alaska , Climate Change , Female , Humans , Male , Minority Groups , Quality of Life , United States , United States Environmental Protection Agency
12.
Opt Express ; 22(1): 1152-62, 2014 Jan 13.
Article in English | MEDLINE | ID: mdl-24515075

ABSTRACT

Oblique back-illumination microscopy (OBM) provides high resolution, sub-surface phase-gradient images from arbitrarily thick samples. We present an image formation theory for OBM and demonstrate that OBM lends itself to volumetric imaging because of its capacity for optical sectioning. In particular, OBM can provide extended depth of field (EDOF) images from single exposures, by rapidly scanning the focal plane with an electrically tunable lens. These EDOF images can be further enhanced by deconvolution. We corroborate our theory with experimental volumetric images obtained from transparent bead samples and mouse cortical brain slices.


Subject(s)
Cerebral Cortex/cytology , Imaging, Three-Dimensional/instrumentation , Lenses , Lighting/instrumentation , Microscopy/instrumentation , Nephelometry and Turbidimetry/instrumentation , Nephelometry and Turbidimetry/methods , Animals , Equipment Design , Equipment Failure Analysis , Mice
13.
Microb Ecol ; 67(3): 489-500, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24477922

ABSTRACT

Satellite-based remote sensing of marine microorganisms has become a useful tool in predicting human health risks associated with these microscopic targets. Early applications were focused on harmful algal blooms, but more recently methods have been developed to interrogate the ocean for bacteria. As satellite-based sensors have become more sophisticated and our ability to interpret information derived from these sensors has advanced, we have progressed from merely making fascinating pictures from space to developing process models with predictive capability. Our understanding of the role of marine microorganisms in primary production and global elemental cycles has been vastly improved as has our ability to use the combination of remote sensing data and models to provide early warning systems for disease outbreaks. This manuscript will discuss current approaches to monitoring cyanobacteria and vibrios, their activity and response to environmental drivers, and will also suggest future directions.


Subject(s)
Aquatic Organisms/physiology , Cyanobacteria/physiology , Environment , Environmental Monitoring/methods , Remote Sensing Technology , Vibrio/physiology , Oceans and Seas , Spacecraft
14.
J Biomed Opt ; 18(6): 066007, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23733023

ABSTRACT

Oblique back-illumination microscopy (OBM) is a new technique for simultaneous, independent measurements of phase gradients and absorption in thick scattering tissues based on widefield imaging. To date, OBM has been used with sequential camera exposures, which reduces temporal resolution, and can produce motion artifacts in dynamic samples. Here, a variation of OBM that allows single-exposure operation with wavelength multiplexing and image splitting with a Wollaston prism is introduced. Asymmetric anamorphic distortion induced by the prism is characterized and corrected in real time using a graphics-processing unit. To demonstrate the capacity of single-exposure OBM to perform artifact-free imaging of blood flow, video-rate movies of microcirculation in ovo in the chorioallantoic membrane of the developing chick are presented. Imaging is performed with a high-resolution rigid Hopkins lens suitable for endoscopy.


Subject(s)
Endoscopy/instrumentation , Microcirculation , Microscopy, Video/methods , Algorithms , Animals , Artifacts , Chick Embryo , Chorioallantoic Membrane/pathology , Computer Graphics , Endoscopy/methods , Equipment Design , Light , Lighting , Motion , Optics and Photonics/methods , Software , Time Factors
15.
Foot Ankle Spec ; 6(3): 236-8, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23548587

ABSTRACT

Bone wax has been used for years by surgeons as a hemostatic agent to prevent bleeding from bone surfaces. Though the effectiveness of bone wax as a hemostatic agent while acting as a tamponade is well known, it is not without its complications. It has been documented in the medical literature that bone wax may remain in the body for many years as a foreign body and in some cases cause a giant cell reaction at various surgical sites. However, to the authors' knowledge, there has not been a reported case of a foreign body giant cell reaction secondary to the use of bone wax in the current podiatric literature. Two case studies are described to bring attention to the fact that bone wax can interfere with bone healing while remaining attached to bone as a foreign body and induce a giant cell reaction and local inflammatory effects in the human foot.


Subject(s)
Foreign-Body Reaction/surgery , Granuloma, Giant Cell/surgery , Hemostatics/adverse effects , Palmitates/adverse effects , Postoperative Complications/surgery , Waxes/adverse effects , Adolescent , Debridement , Female , Humans , Magnetic Resonance Imaging , Male , Metatarsophalangeal Joint/surgery , Middle Aged , Subtalar Joint/surgery , Therapeutic Irrigation
16.
Plant Dis ; 97(5): 601-607, 2013 May.
Article in English | MEDLINE | ID: mdl-30722192

ABSTRACT

Thousand cankers disease (TCD) of walnut is a result of feeding in the phloem by the walnut twig beetle (WTB), Pityophthorus juglandis, and subsequent canker formation caused by Geosmithia morbida around galleries. TCD has caused extensive morbidity and mortality to Juglans nigra in the western United States and, in 2010, was discovered in the eastern United States, where the tree is a highly valuable timber resource. WTB and G. morbida also have been found in J. regia orchards throughout major production areas in California, and the numbers of damaged trees are increasing. We tested the susceptibility of walnut and hickory species to G. morbida in greenhouse and field studies. Carya illinoinensis, C. aquatica, and C. ovata were immune. All walnut species tested, including J. ailantifolia, J. californica, J. cinerea, J. hindsii, J. major, J. mandshurica, J. microcarpa, J. nigra, and J. regia, developed cankers following inoculation with G. morbida. J. nigra was the most susceptible, whereas J. major, a native host of the WTB and, presumably, G. morbida, had smaller and more superficial cankers. Canker formation differed among maternal half-sibling families of J. nigra and J. cinerea, indicating genetic variability in resistance to G. morbida. Our inoculation studies with G. morbida have corroborated many of the field observations on susceptibility of walnut and hickory species to TCD, although the ability of the WTB to successfully attack and breed in walnut is also an important component in TCD resistance.

17.
Nat Methods ; 9(12): 1195-7, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23103879

ABSTRACT

Phase-contrast techniques, such as differential interference contrast microscopy, are widely used to obtain morphological images of unstained biological samples. The transillumination geometry required for these techniques restricts their application to thin samples. We introduce oblique back-illumination microscopy, a method of collecting en face phase-gradient images of thick scattering samples, enabling near-video-rate in vivo phase imaging with a miniaturized probe suitable for endoscopy.


Subject(s)
Microscopy/methods , Animals , Chick Embryo , Diagnostic Imaging , Endoscopy/instrumentation , Lighting/methods , Mice , Microscopy, Phase-Contrast/methods , Miniaturization , Transillumination
18.
Opt Lett ; 37(19): 4062-4, 2012 Oct 01.
Article in English | MEDLINE | ID: mdl-23027279

ABSTRACT

We present a technique to quantitatively image the phase of thin quasi-transparent samples using extended source incoherent illumination and off-axis detection apertures. Our technique is achromatic and polarization independent, requires no active elements, and can be readily adapted to standard bright-field microscopes. We demonstrate our technique by quantitatively reconstructing the phase of cheek cells and a microlens. The light efficient, single-shot nature of our technique enables phase imaging at frame rates that are camera limited.


Subject(s)
Optical Imaging/instrumentation , Calibration , Cheek , Equipment Design
19.
J Biomed Opt ; 17(2): 021105, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22463023

ABSTRACT

We describe a nonscanning, fiber bundle endomicroscope that performs optically sectioned fluorescence imaging with fast frame rates and real-time processing. Our sectioning technique is based on HiLo imaging, wherein two widefield images are acquired under uniform and structured illumination and numerically processed to reject out-of-focus background. This work is an improvement upon an earlier demonstration of widefield optical sectioning through a flexible fiber bundle. The improved device features lateral and axial resolutions of 2.6 and 17 µm, respectively, a net frame rate of 9.5 Hz obtained by real-time image processing with a graphics processing unit (GPU) and significantly reduced motion artifacts obtained by the use of a double-shutter camera. We demonstrate the performance of our system with optically sectioned images and videos of a fluorescently labeled chorioallantoic membrane (CAM) in the developing G. gallus embryo. HiLo endomicroscopy is a candidate technique for low-cost, high-speed clinical optical biopsies.


Subject(s)
Anatomy, Cross-Sectional/instrumentation , Chick Embryo/cytology , Endoscopes , Image Enhancement/instrumentation , Lenses , Microscopy/instrumentation , Animals , Computer Systems , Equipment Design , Equipment Failure Analysis
20.
Environ Sci Technol ; 45(8): 3547-53, 2011 Apr 15.
Article in English | MEDLINE | ID: mdl-21417444

ABSTRACT

A newly designed primer set (AnnirS), together with a previously published primer set (ScnirS), was used to detect anammox bacterial nirS genes from sediments collected from three marine environments. Phylogenetic analysis demonstrated that all retrieved sequences were clearly different from typical denitrifiers' nirS, but do group together with the known anammox bacterial nirS. Sequences targeted by ScnirS are closely related to Scalindua nirS genes recovered from the Peruvian oxygen minimum zone (OMZ), whereas sequences targeted by AnnirS are more closely affiliated with the nirS of Candidatus 'Kuenenia stuttgartiensis' and even form a new phylogenetic nirS clade, which might be related to other genera of the anammox bacteria. Analysis demonstrated that retrieved sequences had higher sequence identities (>60%) with known anammox bacterial nirS genes than with denitrifiers' nirS, on both nucleotide and amino acid levels. Compared to the 16S rRNA and hydrazine oxidoreductase (hzo) genes, the anammox bacterial nirS not only showed consistent phylogenetic relationships but also demonstrated more reliable quantification of anammox bacteria because of the single copy of the nirS gene in the anammox bacterial genome and the specificity of PCR primers for different genera of anammox bacteria, thus providing a suitable functional biomarker for investigation of anammox bacteria.


Subject(s)
Bacteria, Anaerobic/genetics , Bacterial Proteins/genetics , Cytochromes/metabolism , Nitrite Reductases/metabolism , Quaternary Ammonium Compounds/metabolism , Anaerobiosis , Bacteria, Anaerobic/classification , Bacteria, Anaerobic/metabolism , Bacterial Proteins/analysis , Bacterial Proteins/metabolism , Base Sequence , Biodiversity , Biomarkers/analysis , Biomarkers/metabolism , Cytochrome c Group , Genes, Bacterial , Geologic Sediments/chemistry , Geologic Sediments/microbiology , Molecular Sequence Data , Oxidation-Reduction , Phylogeny , RNA, Ribosomal, 16S , Seawater/chemistry , Seawater/microbiology
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