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We demonstrate a microfluidics-based fluorescence detection device where the filters, source, detector, and electronically controlled valves are embedded into a Polydimethylsiloxane (PDMS)-based microfluidic chip. The device reported here has been specifically designed for chlorophyll a fluorescence sensing in autonomous systems, such as oceanic applications. In contrast to a monolithic approach, the modular approach made the fabrication of this device simpler and cheaper. For fluorescence detection, an InGaN/GaN LED is used as the excitation source to specifically excite chlorophyll a; a metal-dielectric Fabry–Perot filter was used to extinguish out-of-band excitation. A simple Si photodiode is used as detector and provided with a thermally evaporated CdS emission filter to block the excitation source. This filter combination provides an excellent solution to the difficult problem of combining high-rejection excitation and emission filters in an integrated thin-film format. Furthermore, the metal-dielectric filter provides a much broader angular response than a comparable multilayer Bragg mirror, which is a key advantage in the integrated format. We use a novel paraffin wax-based valve design affords low power single-use actuation, between 0.5 and 1 J per actuation and withstands 0.6 bar differential pressure, which provides better performance than its previously reported counterparts. The remote valve-controlled operation of the fluorescence detection system is demonstrated, illustrating the measurement of a chlorophyll a solution, with a detection limit of 340 μM and subsequent valve-controlled flushing of the measurement reservoir.

Antibiotic treatment in such cases is warranted ( Vereecken and others 1998 ). [...]recently, there has been little difficulty in selecting an appropriate antibiotic, as E coli has been sensitive to a range of different types. Antibiotic Number resistant/number tested (5) Amoxicillin 20/35 (57) Ampicillin 19/33 (58) Amoxicillin/clavulanate 9/36 (25) Apramycin 2/34 (6) Enrofloxacin 3/39 (8) Erythromycin 31/32 (97) Lincomycin/spectinomycin 10/34 (29) Neomycin 26/31 (84) Tetracycline 24/39 (62) Potentiated sulfonamides 22/39 (56) Overall, 56 per cent of isolates were determined as resistant to more than five antibiotics on their antibiogram using the disc diffusion method.

Pigeon circovirus (picv) was detected in cloacal swab samples by means of a newly-developed, sensitive pcr. An initial investigation of 17 Belgian racing pigeons aged up to eight months showed that rates of detection of 88 per cent and above were achieved using samples of cloacal swab, blood and bursa of Fabricius. The sampling of 15 caged pigeons six times when they were from three to 31 weeks of age indicated that picv infections were more readily detected in cloacal swabs than in blood, and that the virus could be detected in cloacal swabs for longer periods after infection than in blood. picv infections were detected in cloacal swabs from 38 of 47 young pigeons aged from two to 31 weeks, from 12 racing lofts, which had clinical signs including diarrhoea and weight loss, regurgitation and respiratory signs. Samples from birds from two infected lofts indicated that picv could be detected in some birds for at least 27 weeks. Although nine of 14 pigeons aged from 32 to 45 weeks were virus-positive, picv was detected in only one of 18 adult pigeons that originated from four infected lofts.

âYoung bird sicknessâ is a term used by racing pigeon fanciers to describe a condition that has occurred regularly in recent years and affects pigeons (Columba livia domestica) in their first year of life. It is characterized by slow crop emptying, regurgitation, diarrhea, weight loss, poor performance, and occasionally death. Little scientific information is known about this syndrome to differentiate it from other diseases that occur in young pigeons. In this study, 1 bird from each of 9 lofts where âyoung bird sicknessâ was reported was euthanatized for cytologic and postmortem examination. Lesions of the lymphoreticular system, alimentary tract, and respiratory system were the most common findings. Lesions of the lymphoreticular system were present in all birds examined, and 3 birds had histopathologic findings consistent with circovirus infection. Combinations of protozoal, fungal, and mixed bacterial infections were associated with ingluvitis in 7 birds and enteritis in 6 birds. Pneumonitis was found in 5 birds that tested positive for Chlamydophila by polymerase chain reaction. Although âyoung bird sicknessâ appears to be a multifactorial condition, a pattern of lesions that involved the lymphoreticular, gastrointestinal, and respiratory systems was evident, whereas diseases of other organ systems were uncommon. These findings suggest that âyoung bird sicknessâ may have a common etiology, and circovirus infection is proposed as a possible initiating cause of this syndrome in young racing pigeons in Northern Ireland.

Optical biosensors are increasingly being considered for lab-on-a-chip applications due to their benefits such as small size, biocompatibility, passive behaviour and lack of the need for fluorescent labels. The light guiding mechanisms used by many of them results in poor overlap of the optical field with the target molecules, reducing the maximum sensitivity achievable. This review article presents a new platform for optical biosensors, namely slotted photonic crystals, which provide higher sensitivities due to their ability to confine, spatially and temporally, the optical mode peak within the analyte itself. Loss measurements showed values comparable to standard photonic crystals, confirming their ability to be used in real devices. A novel resonant coupler was designed, simulated, and experimentally tested, and was found to perform better than other solutions within the literature. Combining with cavities, microfluidics and biological functionalization allowed proof-of-principle demonstrations of protein binding to be carried out. Higher sensitivities were observed in smaller structures than possible with most competing devices reported in the literature. This body of work presents slotted photonic crystals as a realistic platform for complete on-chip biosensing; addressing key design, performance and application issues, whilst also opening up exciting new ideas for future study.

The Atacama Large Millimeter/submillimeter Array (ALMA) is a new powerful tool for observing the Sun at high spatial, temporal, and spectral resolution. These capabilities can address a broad range of fundamental scientific questions in solar physics. The radiation observed by ALMA originates mostly from the chromosphere—a complex and dynamic region between the photosphere and corona, which plays a crucial role in the transport of energy and matter and, ultimately, the heating of the outer layers of the solar atmosphere. Based on first solar test observations, strategies for regular solar campaigns are currently being developed. State-of-the-art numerical simulations of the solar atmosphere and modeling of instrumental effects can help constrain and optimize future observing modes for ALMA. Here we present a short technical description of ALMA and an overview of past efforts and future possibilities for solar observations at submillimeter and millimeter wavelengths. In addition, selected numerical simulations and observations at other wavelengths demonstrate ALMA’s scientific potential for studying the Sun for a large range of science cases.

Background: Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide. A comprehensive and detailed understanding of COPD care pathways from pre- diagnosis to acute care is required to understand the common barriers to optimal COPD care across diverse health systems. Methods: Country-specific COPD care pathways were created for four high-income countries using international recommendations and country-specific guidelines, then populated with published epidemiological, clinical, and economic data. To refine and validate the pathways, semi-structured interviews using pre-prepared discussion guides and country-specific pathway maps were held with twenty-four primary and secondary care respiratory healthcare professionals. Thematic analysis was then performed on the interview transcripts. Results: The COPD care pathway showed broad consistency across the countries. Three key themes relating to barriers in optimal COPD management were identified across the countries: journey to diagnosis, treatment, and the impact of COVID-19. Common barriers included presentation to healthcare with advanced COPD, low COPD consideration, and sub-optimal acute and chronic disease management. COVID-19 has negatively impacted disease management across the pathway but presents opportunities to retain virtual consultations. Structural factors such as insurance and short duration of appointments also impacted the diagnosis and management of COPD. Conclusion: COPD is an important public health issue that needs urgent prioritization. The use of Evidenced Care Pathways with decision-makers can facilitate evidence-based decision making on interventions and policies to improve care and outcomes for patients and reduce unnecessary resource use and associated costs for the healthcare provider/payer. Keywords: health policy, COPD management, COPD diagnosis, exacerbations, qualitative, pathway mapping

Protontherapy has emerged as more effective in the treatment of certain tumors than photon based therapies. However, significant capital and operational costs make protontherapy less accessible. This has stimulated interest in alternative proton delivery approaches, and in this context the use of laser-based technologies for the generation of ultra-high dose rate ion beams has been proposed as a prospective route. A better understanding of the radiobiological effects at ultra-high dose-rates is important for any future clinical adoption of this technology. In this study, we irradiated human skin fibroblasts-AG01522B cells with laser-accelerated protons at a dose rate of 10 9  Gy/s, generated using the Gemini laser system at the Rutherford Appleton Laboratory, UK. We studied DNA double strand break (DSB) repair kinetics using the p53 binding protein-1(53BP1) foci formation assay and observed a close similarity in the 53BP1 foci repair kinetics in the cells irradiated with 225 kVp X-rays and ultra- high dose rate protons for the initial time points. At the microdosimetric scale, foci per cell per track values showed a good correlation between the laser and cyclotron-accelerated protons indicating similarity in the DNA DSB induction and repair, independent of the time duration over which the dose was delivered.