Efficacy, safety, and user experience of DIY or open-source artificial pancreas systems: a systematic review.

The do-it-yourself artificial pancreas system (DIYAPS) is a patient-driven initiative with the potential to revolutionise diabetes management, automating insulin delivery with existing pumps and CGM combined with open-source algorithms. Given the considerable interest in this topic within the diabetes community, we have conducted a systematic review of DIYAPS efficacy, safety, and user experience. Following recognised procedures and reporting standards, we identified 10 eligible publications of 730 participants within the peer-reviewed literature. Overall, studies reported improvements in time in range, HbA1c (glycated haemoglobin), reduced hypoglycaemia, and improved quality of life with DIYAPS use. While results were positive, the identified studies were small, and the majority were observational and at high risk of bias. Further research including well-designed randomised trials comparing DIYAPS with appropriate comparators is recommended.

Effect of operating conditions on yield and quality of biocrude during hydrothermal liquefaction of halophytic microalga Tetraselmis sp.

The biomass of halophytic microalga Tetraselmis sp. with 16%w/w solids was converted into biocrude by a hydrothermal liquefaction (HTL) process in a batch reactor at different temperatures (310, 330, 350 and 370°C) and reaction times (5, 15, 30, 45 and 60min). The biocrude yield, elemental composition, energy density and severity parameter obtained at various reaction conditions were used to predict the optimum condition for maximum recovery of biocrude with improved quality. This study clearly indicated that the operating condition for obtaining maximum biocrude yield and ideal quality biocrude for refining were different. A maximum biocrude yield of ∼65wt% ash free dry weight (AFDW) was obtained at 350°C and 5min, with a severity parameter and energy density of 5.21 and ∼35MJ/kg, respectively. The treatment with 45min reaction time recorded ∼62wt% (AFDW) yield of biocrude with and energy density of ∼39MJ/kg and higher severity parameter of 7.53.

Pilot-scale continuous recycling of growth medium for the mass culture of a halotolerant Tetraselmis sp. in raceway ponds under increasing salinity: a novel protocol for commercial microalgal biomass production.

The opportunity to recycle microalgal culture medium for further cultivation is often hampered by salinity increases from evaporation and fouling by dissolved and particulate matter. In this study, the impact of culture re-use after electro-flocculation of seawater-based medium on growth and biomass productivity of the halotolerant green algal strain Tetraselmis sp., MUR 233, was investigated in pilot-scale open raceway ponds over 5months. Despite a salinity increase from 5.5% to 12% (w/v) NaCl, Tetraselmis MUR 233 grown on naturally DOC-enriched recycled medium produced 48-160% more ash free dry weight (AFDW) biomass daily per unit pond area than when grown on non-recycled medium. A peak productivity of 37.5±3.1gAFDWm(-2)d(-1) was reached in the recycled medium upon transition from ∼14% to ∼7% NaCl. The combination of high biomass-yielding mixotrophic growth under high salinity has been proven to be a successful sustainable cultivation strategy.

Biofilm establishment and heavy metal removal capacity of an indigenous mining algal-microbial consortium in a photo-rotating biological contactor.

An indigenous mining algal-microbial consortium was immobilised within a laboratory-scale photo-rotating biological contactor (PRBC) that was used to investigate the potential for heavy metal removal from acid mine drainage (AMD). The microbial consortium, dominated by Ulothrix sp., was collected from the AMD at the Sar Cheshmeh copper mine in Iran. This paper discusses the parameters required to establish an algal-microbial biofilm used for heavy metal removal, including nutrient requirements and rotational speed. The PRBC was tested using synthesised AMD with the multi-ion and acidic composition of wastewater (containing 18 elements, and with a pH of 3.5 ± 0.5), from which the microbial consortium was collected. The biofilm was successfully developed on the PRBC's disc consortium over 60 days of batch-mode operation. The PRBC was then run continuously with a 24 h hydraulic residence time (HRT) over a ten-week period. Water analysis, performed on a weekly basis, demonstrated the ability of the algal-microbial biofilm to remove 20-50 % of the various metals in the order Cu > Ni > Mn > Zn > Sb > Se > Co > Al. These results clearly indicate the significant potential for indigenous AMD microorganisms to be exploited within a PRBC for AMD treatment.

Plankton predation rates in turbulence: a study of the limitations imposed on a predator with a non-spherical field of sensory perception.

This paper presents an extension to previously published work which studied encounter rates of planktonic predators with restricted perception fields, to examine the related problems of prey capture and predation rates. Small-scale turbulence influences planktonic predation in two ways: the extra energy of the flow enhances the number of encounter events between individual predator and prey meso/micro-zooplankton, but it lowers the capture probability (because the time spent by the predator and prey in close proximity is reduced). Typically, an 'encounter' has usually been defined as an event when a potential prey swims (or is advected) to within a distance R of the predator in any direction. However, there is a considerable body of experimental evidence showing that predators perception fields are far from spherical; often they are wedge shaped (e.g. fish larvae), or strongly aligned with the directions of sensory antennae (e.g. copepods); and this is certain to influence optimal predation strategies. This paper presents a theoretical model which for the first time examines the combined problems of both encounter and capture for a predator with a restricted perception field swimming in a turbulent flow. If such a predator adopts a cruising strategy (continuous swimming, possibly with direction changes) the model predictions suggest that predation rates actually vary little with swimming speed, in contrast to predictions made for spherical perception fields. Consequently, cruising predators are predicted to swim at relatively low speeds whilst foraging. However, application of the model to examine the net energy gain of a typical pause-travel predator (the Atlantic cod larva), does predict the existence of an optimal ratio of the length of pauses to time spent swimming (specifically one pause phase to every two travel phases), in line with experimental observations. Kinematic simulations are presented which support these findings.

The production and characterization of monoclonal antibodies to the fungus Aspergillus versicolor.

UNLABELLED: Fungal exposure measurements in indoor environments require accurate and precise monitoring methods. Such techniques may be based on monoclonal antibodies (Mabs) and enzyme-linked immunosorbent assays (ELISA) and here we report the cross-reactivity patterns of Mabs produced against Aspergillus versicolor. Balb/c mice were immunized with the particulate fraction of homogenized spores and 46 Mabs (35 IgM, nine IgG3, two IgG1) were produced and tested for cross-reactivity against 55 fungal species. None of the Mabs was found to be species-specific for A. versicolor. Several Mabs strongly cross-reacted with most Aspergillus, Penicillium and Eurotium species and some Mabs also cross-reacted with Paecilomyces variotii and several Cladosporium and Stachybotrys species. Our results show that antibody responses in mice against spores of A. versicolor are dominated by highly cross-reactive antibodies of the IgM isotype. The widespread cross-reactivity suggests that the specificity of antibodies to be used for the detection of fungi in environmental samples need to be thoroughly characterized in order to avoid ambiguities in the interpretation of monitoring results. Furthermore, accurate estimates of spore concentrations may require the application of species-specific Mabs in order to avoid bias in result interpretation because of the differential reactivity of cross-reactive Mabs with different fungi. PRACTICAL IMPLICATIONS: Producers of monoclonal or polyclonal antibodies for the detection of fungi in environmental or clinical samples need to verify antibody reactivity patterns and accurately report that information to potential users. Furthermore, immunoassays based on mouse or human serum or purified immunoglobulin fractions need to consider antibody cross-reactivity as a potential confounding factor during interpretation of results.

A simple model of plankton population dynamics coupled with a LES of the surface mixed layer.

The concentration of phytoplankton in the sea is affected by biological processes, such as growth/mortality rates, predatory zooplankton concentrations and nutrient levels. Phytoplankton concentrations are also influenced by physical processes, in particular the mixing properties of the local fluid environment. On planktonic scales (approximately 10-1000 microm) one can assume the local turbulent flow is isotropic, with no distinction between horizontal and vertical mixing. However, agglomerations of phytoplankton into patches are observed on larger scales of up to hundreds of metres, whose formation will be influenced by the anisotropic advection/mixing properties and large-eddy structures prevalent in the surface mixed layer. This paper presents the results of the coupling of a large-eddy simulation (LES) model of the mixed layer with an advection-diffusion system of coupled equations for nitrate-phytoplankton-zooplankton (NPZ) concentration, incorporating sub-grid parameterizations of the biological processes. Typically these include phytoplankton growth due to light levels and ambient nitrate concentration, offset by grazing losses due to the presence of zooplankton. The primary goal of this work is to investigate how the characteristics of the mixed layer turbulence influence the observed distribution of phytoplankton. One novel feature is the incorporation of a 'vortex-force' term in the LES code in order to generate Langmuir circulations. It has been speculated that the enhanced mixing rates associated with 'Langmuir turbulence' play a significant role in regulating planktonic activity. Results derived from the coupled LES-NPZ model, run with and without the presence of Langmuir circulations, are presented in order to investigate these ideas.

Determination of soluble aluminium concentration in alkaline humic water using atomic absorption spectrophotometry.

The steps of the standard method to determine soluble aluminium concentration are filtering, followed by acidifying, then analysing with the atomic absorption spectrophotometer (AAS). When applied to alkaline humic water, acidification gives rise to the formation of humic acid as a brown particulate matter. Of the total soluble aluminium in the original water, 49-61% forms complexes with the particulate humic acid upon acidification. Although the AAS is capable of detecting the binding aluminium, the particulate nature of humic acid easily induces inaccurate readings as a result of the non-uniform distribution of the particulate matter. A more precise analysis of soluble aluminium concentration of alkaline humic water is shown to be achievable in basicified solutions instead. Basicified solutions keep humic acid in the soluble form; hence maintain the homogeneity of the sample.

Limitations of monoclonal antibodies for monitoring of fungal aerosols using Penicillium brevicompactum as a model fungus.

Molds are ubiquitous in every environment and many species have been recently associated with an increase in opportunistic infections in immunocompromised patients or the exacerbation of asthmatic episodes in allergic patients. The degree of environmental contamination with fungi thus needs to be monitored and in this study we report the development of a monoclonal antibody (mAb)-mediated enzyme-linked immunosorbent assay (ELISA) for the detection of spores of Penicillium brevicompactum in experimental model aerosols. In addition, we have investigated the influence of different parameters of air sampling and sample recovery on ELISA performance. MAbs were produced with standard hybridoma techniques and cross-reactivities were determined against spores of 53 fungal species by indirect ELISA. Standardized experimental fungal aerosols were collected with the Button Personal Inhalable Aerosol Sampler onto polycarbonate or polytetrafluoroethylene filters (PTFE) and the effects of different extraction buffers and filter agitation methods during sample processing on spore recovery and ELISA detection were investigated. Five mAbs were produced and all of them cross-reacted with several of 31 related Aspergillus, Penicillium and Eurotium species. However, cross-reactivities with 21 non-related fungi were rare. Spores were recovered in much higher numbers from polycarbonate filters (PFs) than from polytetrafluoroethylene filters. Optical densities (ODs) in ELISA were higher for spores collected into carbonate coating buffer (CCB) than phosphate-buffered saline (PBS). Filter bath sonication following filter vortexing had no positive effects on ELISA sensitivity. The cross-reactivity patterns of mAbs suggest that Aspergillus and Penicillium species share multiple antigens. Quantitative ELISA results for fungal aerosols were found to be influenced by differential sample processing and thus method standardization will be essential to maintain the comparability of immunometric monitoring results.

Planktonic encounter rates in homogeneous isotropic turbulence: the case of predators with limited fields of sensory perception.

It is a well-established fact that encounter rates between different species of planktonic microorganism, either swimming, or passively advected by the flow, are enhanced in the presence of turbulence. However, due to the complexity of the various calculations involved, current encounter rate theories are based on a number of simplifying approximations, which do not reflect reality. In particular, a typical planktonic predator is usually assumed to have perfect 'all round vision', i.e. it can perceive a prey particle at any relative orientation, provided it lies within some given contact radius R. Unfortunately, there is a wide body of experimental evidence that this is not the case. In this study the encounter problem for a predator with a limited field of sensory perception, swimming in a turbulent flow, is examined from first principles and a number of new modelling ideas proposed. A wide range of kinematic simulations are also undertaken to test these predictions. Particular attention is paid to the swimming strategy such a predator might undertake to enhance its encounter rate. It turns out that the predicted optimum swimming strategies differ radically from the results of previous work. Empirical evidence is also presented which appears to support these new findings.

Dose-response and time course of specific IgE and IgG after single and repeated topical skin exposure to dry trimellitic anhydride powder in a Brown Norway rat model.

BACKGROUND: Trimellitic anhydride (TMA)-induced occupational asthma is thought to be associated with its ability to acylate proteins and to induce production of TMA-specific immunoglobulin (Ig)E. Though the respiratory tract is considered to be a major exposure route leading to airway sensitization, the potential role of dermal exposure producing asthmatic sensitization is not known. The present study examines the ability of dry TMA powder to sensitize Brown Norway rats when applied, topically, to the skin. METHODS: A patch of hair was carefully clipped with scissors on the rat's back. Dry TMA powder (0.3, 1.25, 5 and 20 mg) was administered on days 0, 7, 14 and 21, and the area occluded with surgical tape overnight after each application. Residual powder recovered from the occluded skin was analyzed by proton nuclear magnetic resonance and was still predominantly TMA. Circulating anti-TMA IgE and IgG were measured by ELISA. RESULTS: TMA elicited dose-dependent production of specific IgE and IgG. Specific antibodies were detectable 2 weeks after the first TMA exposure and peaked between 3 and 4 weeks. CONCLUSION: The data suggest that topical skin exposure to dry TMA powder can induce allergic/immunological sensitization as demonstrated by the production of specific antibodies.

Kinetics of changes in lymphocyte sub-populations in mouse lungs after intrapulmonary infection with M. bovis (Bacillus Calmette-Guerin) and identity of cells responsible for IFNgamma responses.

Gamma interferon (IFNgamma) plays a key role in host defense against pulmonary mycobacterial infections. A variety of lymphocyte subsets may participate in producing pulmonary IFNgamma responses, but their relative contributions after mycobacterial infection have not been clearly elucidated. To address this question, C57Bl/6 female mice were infected by intrapulmonary instillation of 2.5 x 104 BCG (Mycobacterium bovis Bacillus Calmette-Guerin). Lymphocyte populations in lung interstitium were examined at different time points after the infection. BCG load in lungs peaked between 4 and 6 weeks post-infection and declined to very low levels by the 12th week of infection. Recovery of lung interstitial lymphocytes doubled by 4-6 weeks after infection and declined thereafter. Flow cytometric analysis of the lung-derived lymphocytes revealed that about 5% of the these cells made IFNgamma in control mice, and this baseline IFNgamma production involved T (CD3+NK1.1-), NK (CD3-NK1.1+) and NKT (CD3+NK1.1+) cells. As the BCG lung infection peaked, the total number of CD3+ T cells in the lungs increased threefold at 5-6 weeks post-infection. There was a marked increase (sixfold) in the number of T cells secreting IFNgamma 5-6 weeks post-infection. Some increase was also noted in the NKT cells making IFNgamma, but the numbers of NK cells making IFNgamma in BCG-infected lungs remained unaltered. Our results suggest that whereas NK and NKT cells contribute to baseline IFNgamma secretion in control lungs, expansion in the IFNgamma-producing T-cell population was essentially responsible for the augmented response seen in lungs of BCG-infected mice.

Differences in expression, actions and cocaine regulation of two isoforms for the brain transcriptional regulator NAC1.

BTB/POZ proteins can influence the cell cycle and contribute to oncogenesis. Many family members are present in the mammalian CNS. Previous work demonstrated elevated NAC1 mRNA levels in the rat nucleus accumbens in response to cocaine. NAC1 acts like other BTB/POZ proteins that regulate transcription but is unusual because of the absence of identifiable DNA binding domains. cDNAs were isolated encoding two NAC1 isoforms differing by only 27 amino acids (the longer isoform contains 514 amino acids). The mRNAs for both isoforms were simultaneously expressed throughout the rat brain and peripheral tissues. Semi-quantitative reverse transcription-polymerase chain reaction analysis revealed that the mRNA of the longer isoform was more abundant than the mRNA of the shorter isoform. Western blot analysis demonstrated a similar unequal distribution between the isoforms in the CNS. The longer isoform was the more abundant of the two NAC1 proteins and the ratio between them differed throughout the rat brain. The shorter isoform was not detected in most of the examined peripheral tissues, suggesting differences from the CNS in post-transcriptional processing. Both isoforms repressed transcription in H293T cells using a Gal4-luciferase reporter system. However, the shorter isoform did not repress transcription as effectively as the longer isoform. Transfection of different ratios for both isoforms, in order to replicate the relative amounts observed throughout the CNS, supported an interaction between the isoforms. The net effect on transcriptional repression was determined by the ratio of the two NAC1 isoforms. Each isoform exhibited the subnuclear localization that is characteristic of many BTB/POZ proteins. A rapid and transient increase in the level of the shorter isoform occurred in the nucleus accumbens 2 h following a single i.p. cocaine injection. We conclude that the two isoforms of NAC1 may differentially affect neuronal functions, including the regulation of cocaine-induced locomotion.

Responding to a violent incident: physical restraint or anger management as therapeutic interventions.

By finding more feasible alternatives to managing aggression which can be effectively used in health care settings, as well as expanding nursing knowledge on the detrimental effects of restraints, forensic clinicians can use their creativity and resources to enhance the quality of life for their patients using beneficial therapeutic alternatives to restraint. A closer examination of alternatives to managing aggressive behaviour leads the author to the introduction of a case study, promoting non-touch interventions. The importance of this paper lies in reorienting forensic clinicians away from the perceived ideologies of physical restraint as a primary intervention, moving towards the productive use of anger management.

Infrainguinal vein graft surveillance: the criteria for intervention.

In most patients, infrainguinal vein grafts are commonly performed for limb-threatening ischemia. Once limb salvage has been achieved, most clinicians agree that regular appointments with the vascular team are important to monitor graft patency. However, the timing of these appointments and what defines an adequate examination remains debatable. The following cases illustrate the natural history and interventions performed in 2 such patients. A review of the literature and a commentary on surveillance strategies is provided to elucidate the advantages and disadvantages of currently available vascular laboratory testing. Recommendations also are made for the appropriate timing of intervention to revise these grafts.

Characterization of asphalt fume composition under simulated road paving conditions by GC/MS and microflow LC/quadrupole time-of-flight MS.

A highly sensitive, selective, and reliable analytical method has been developed and validated for characterization of asphalt fume generated under simulated road paving conditions. A dynamic asphalt fume generation system was modified to provide consistent test atmospheres at simulated asphalt road paving conditions. In the process of fume generation, asphalt was initially preheated in an oven to 170 degrees C, pumped to a large kettle, which maintained the asphalt temperature between 150 and 170 degrees C, and then transferred to the generator. The fume was conducted from the generator to an exposure chamber through a heated transfer line. Characterization of the asphalt fume test atmospheres included the following: (1) determination of the consistency of the asphalt aerosol composition within the generation system; (2) quantification of total organic matter of the asphalt fume by electron impact ionization of isotope dilution gas chromatography/ mass spectrometry); and (3) identification of individual priority polycyclic aromatic hydrocarbons (PAHs) in asphalt fume by selected ion monitoring. With the developed method, asphalt fumes could be characterized into three fractions: (1) filter collection of a large molecular size fraction over a range of mass-to-charge (m/z) ratios of 173-309; (2) XAD-2 trapping of a medium molecular size fraction over a range of m/z ratios of 121-197; and (3) charcoal trapping of a small molecular size fraction that contained mainly the volatile vapor fraction over a range of m/z ratios of 57-141. Total organic matter of the asphalt fume was quantified over the 5 exposure days. Sixteen specific priority PAHs were monitored and identified. These PAHs were determined at trace levels on the filter fraction. A novel approach, which utilizes collision-induced dissociation of fragmentation pathway leading to a characteristic fragmentation pattern by coupling microflow liquid chromatography to atmospheric pressure chemical ionization of quadrupole time-of-flight mass spectrometry, was used to further clarify the trace amount of key components present in simulated road paving asphalt fumes. These results demonstrate that asphalt fume composition could be characterized and specific priority PAHs could be identified by this method. The major advantages of this method are its highly sensitivity, selectivity, and reliability for chemical hazard characterization in a complex mixture. This method is suitable for support toxicity studies using simulated occupational exposure to asphalt fumes.

The influence of turbulence on plankton predation strategies.

The importance of predation in regulating the size of competing plankton and larval fish populations has long been appreciated. However, it has only recently been recognized that turbulence must have a significant influence on predator-prey interactions because most rival species of microorganisms co-exist in oceanic or fast moving fresh water flows. Turbulence is likely to influence predation strategies in two ways. The extra energy imparted to a micro-organism from the flow field will enhance the number of encounters or "contacts" between predators and prey. At the same time, because the velocity of a predator relative to its potential prey will be increased, the time-scale over which a capture must be completed is reduced. Balancing the benefits of extra encounters with the drawbacks of more difficult captures, will dictate an optimal predation strategy, either foraging behaviour or ambush feeding, on the predator. This will depend on its own and the prey's swimming capabilities, as well as the characteristics of the turbulent environment. In this paper some previous work, examining the increased encounter rate in turbulence, will be extended to look at the capture problem. The main proposal is that the capture event should be encapsulated in a capture probability function, from which the optimal predation strategy can be derived. As an illustration, plausible capture probability functions will be postulated and the resulting predictions tested against numerical simulations carried out in a turbulent-like flow field. Good agreement between the predictions and the simulations is demonstrated.