Search

Nutrient losses from agricultural lands are responsible for degrading water quality and accelerating eutrophication at local and regional scale. Subsurface tile drainage is an agricultural water management measure extensively used in some Northwestern European countries to improve poor internal field drainage and crop production. However, drains constitute artificial and direct conduits responsible for shortening the residence time and accelerating nutrient transport through the hydrological system. Thus, they put the aquatic ecosystems at risk since they promote rapid drainage water transport and reduce the possibility for natural nutrient removal. Edge-of-field technologies have been developed and implemented in the last decades to reduce diffuse pollution caused by nitrogen (N) and phosphorus (P) losses. These technologies are primarily used in critical source areas, where measures at farm-scale appear insufficient to meet the removal targets. They are placed at the edge of agricultural fields and connected to the main drainage pipe. Widely recognized technologies include constructed wetlands, woodchips bioreactors, and filter systems. This chapter presents the results obtained in Denmark from three different and currently investigated edge-of-field technologies treating agricultural drainage water.

The air charged through the air charger must be pure and free from impurities; hence, the role of a filter that removes pollutants, such as moisture, oil, and carbides is very important. The lifespan of the filter is approximately 50 h, and if exceeded, the purification function decreases rapidly. Therefore, it must be replaced periodically. However, economic and environmental problems occur in the process of replacing the filter. This study investigated the extension of the filter lifespan (60 h) and enhancement of the purification function. An auto drain system was installed. The pollutant discharge, maximum noise, and lifespan were confirmed through experiments and commissioned inspections to check the performance. The compatibility of the pollutant discharge function and the structure of the auto drain system was verified by checking the discharge of pollutants. In addition, the maximum noise was certified to be less than 80 dB according to the performance-standard. Finally, the charged air quality was analyzed after 60 h of use, and all the analyzed values were confirmed to be within the performance-standard range.

Although numerous bioaerosol samplers for counting and identifying airborne microorganisms are available, the considerably high purchase and maintenance costs for the sampler often prevent broad monitoring campaigns for occupational or environmental surveillance of bioaerosols. We present here a newly developed simple adapter and filter system (TOP filter system) designed to collect bioaerosol particles from a defined air volume using conventional vacuum cleaners as air pumps. We characterized the physical properties of the system using air flow measurements and validated the biological performance. The culture-based detection capacities for airborne fungal species were compared to a standard impaction sampler (MAS-100 NT) under controlled conditions in a bioaerosol chamber (using Trichoderma spores as the test organism) as well as in the field. In the chamber, an overall equivalent detection capacity between all tested filters was recorded, although a significant underrepresentation of the TOP filter system for Trichoderma spores were seen in comparison to the MAS-100 NT. In a comparative field study (n = 345), the system showed similar biological sampling efficiencies compared to the MAS-100 NT impactor, only the diversity of identified fungal communities was slightly lower on the filters. Thus, the system is suitable for large-scale environmental sampling operations where many samples have to be taken in parallel at a given time at distant locations. This system would allow endeavors such as antibiotics resistance monitoring or hygiene surveys in agricultural or occupational settings.

Removal of hexavalent chromium [Cr(VI)] from water was evaluated using a low-cost coated sand adsorbent for potential application in a flow-through filter system using permeable adsorption media. Manganese-aluminum coated sand (MACS) was investigated as a hybrid metal oxide based adsorbent due to the potential efficacy of manganese oxide and aluminum oxide for adsorption of Cr(VI) from water. Adsorbent characterization was performed using XRD, SEM/EDX, XPS and BET. Adsorption experiments were performed to determine adsorption capacity and kinetics. The effect of pH, common co-existing ions found in natural water, and the recyclability of adsorbent were investigated. Adsorbent characterization showed that the MACS sorbent contained aluminum oxide, manganese (III) oxide and manganese (IV) oxide. Adsorption followed the Langmuir and Freundlich adsorption equations, indicating favorable adsorption of Cr(VI) onto the MACS sorbent, while results from the Dubinin-Radushkevich equation were suggestive of physical adsorption of Cr(VI). Cr(VI) adsorption onto the MACS sorbent followed pseudo-second order kinetics. The adsorbent was effective in removing Cr(VI) over a broad pH range from 3 to 9.5, while surface charge analysis confirmed the adsorption of Cr(VI) onto the acidic surface of the MACS sorbent with a pH

En la investigación en laboratorio se evaluó el uso de un material filtrante con base en endocarpio o cáscara de coco (Cocos nucifera) de forma granular para el tratamiento de aguas contaminadas con gasoil de petróleo. Se construyó un sistema de filtros con tubos PVC y se empacaron con el endocarpio, luego de que el mismo fuera triturado manualmente y tamizado a un diámetro de 2 mm. Se utilizaron cinco cantidades de material filtrante (75, 105, 135, 150 y 165 g) y tres concentraciones de gasoil en agua (5, 10 y 15 %). Las muestras de agua contaminada se dejaron fluir a través de los filtros de forma descendente por acción gravitacional y en cada filtrado se determinó la cantidad de aceites y grasas (AyG) a partir de normas internacionales. Los resultados se analizaron estadísticamente mediante ANOVA factorial y test de mínima diferencia significativa de Fisher. Los análisis estadísticos demostraron que existe influencia significativa de los dos factores (% gasoil y cantidad de material filtrante) sobre la variable respuesta en estudio (AyG) con un nivel de confianza de 95 %. Se demostró que el endocarpio de coco con el tamaño de granos utilizado es efectivo para la remoción de hidrocarburos en el agua, al lograrse porcentajes de remoción de 85.10, 84.23 y 82.10 %. Se obtuvo que a mayor cantidad del material filtrante, mayor es el grado de remoción con resultados estadísticamente significativos.

The installed filter system leak test method for cleanrooms and clean zones is described in ISO 14644-3, Cleanrooms and associated controlled environments—Part 3: Test method. Portions of the methods in ISO 14644-3 were adapted from IEST-RP-CC034.4[Schaumburg, Illinois, US: Institute of Environmental Science and Technology], which provides a set of recommended procedures for leak testing HEPA and ULPA filters in situ (in the field) with the aerosol photometer test method and the light scattering airborne particle counter (LSAPC) test method. Leak testing is performed to confirm that the final high efficiency air filter system is properly installed by verifying the absence of bypass leakage in the installation, and that the filters are free of defects (small holes and other damage in the filter medium, frame, seal and leaks in the filter bank framework). This study was conducted to compare the aerosol photometer and LSAPC methods. Testing in the study consisted of creating artificial leaks in the filter system, measuring the upstream and downstream concentrations with the aerosol photometer and with the LSAPC, and comparing the filter leak penetration results. Comparison testing was applied to the procedure for the installed terminal panel filter system leakage scan test (stationary measurement) and the procedure for evaluating overall leakage of high-airflow box-type filters mounted in a duct or air-handling unit (AHU) (overall leakage test). It was found that the aerosol photometer and the LSAPC gave similar results for filter leakage within experimental error. The comparison of the leakage scan tests (stationary measurement) showed that the penetration calculated for the channel ≥ 0.3 μm of the LSAPC with an air flow rate of 1cu ft/min (CFM) (28.3 l/min) was very similar to the penetration measured with the aerosol photometer for a leakage level >0.01 % of the upstream concentration. The comparison result of the overall leakage test showed that overall total penetration values, obtained after dilution of artificial calibrated leaks in the filter media, were identical, within the measurement uncertainty, for particles ≥0.3 μm whether the sampling rate of the LSAPC was 1 CFM (28.3 l/min) or 50 l/min. Several recommendations are provided. In particular, for filters mounted in a duct or AHU where the filter function is critical, the recommended method is the leakage scan test method, using a grid sampling method in a plane downstream of the filter (as agreed between customer and supplier).

In this study, energy resolution dependent on K-Parameters (Trapezoidal filter system optimizing the count rate) of EXOGAM2 detector with newly developed NUMEXO2 digital electronics using 152Eu radioactive source measured and analysed. This experimental study was carried out at the GANIL (Grand Accelerature National d'Ions Lourd) nuclear research center in France. The measurement and analysis results for different K parameters using a 152Eu radioactive source with low and high gamma energy levels were performed for two EXOGAM2 detectors. Without applying any K parameter, the resolution values expressed by FWHM for the 1.EXOGAM2 detector are measured as 2.360% FWHM for (344.2785 keV), 2.820% FWHM for (1408.006 keV), and 2.451% FWHM for (344.2785 keV), 2.975%FWHM for (1408.006 keV) for the 2.EXOGAM2 detector, respectively. For different K parameters (K=2µs, K=5µs ve K=10µs) detail results are shown below., Bu çalışmada, yeni geliştirilen dijital elektronik NUMEXO2 dijital elektronik ile EXOGAM2(EXOtic GAMma array spectrometer) dedektörünün K-Parametrelerine (sayım oranını optimize eden Trapezoidal filtre sistemi) bağlı enerji çözünürlüğü için 152Eu radyoaktif kaynak kullanılarak ölçüm ve analiz yapılmıştır. Yapılan bu deneysel çalışma Fransa’da bulunan GANIL (Grand Accelerature National d’Ions Lourd) nükleer araştırma merkezinde gerçekleştirilmiştir. Düşük ve yüksek gama enerji seviyesine sahip 152Eu radyoaktif kaynak kullanılarak farklı K-parametreleri için gerçekleştirilen ölçüm ve analiz sonuçları iki EXOGAM2 dedektörü için gerçekleştirilmiştir. Herhangi bir K-parametresi uygulamadan 1.EXOGAM2 dedektörü için FWHM ile ifade edilen çözünürlük değerleri sırası ile (344. 2785 keV) için 2.360% FWHM, (1408.006 keV) için 2.820% FWHM olarak ölçülürken 2.EXOGAM2 dedektörü için ise sırasıyla 2.451% FWHM ve 2.975% FWHM olarak ölçülmüştür. Farklı K-parametreleri (K=2µs, K=5µs ve K=10µs) için ise sonuçlar detayları ile aşağıda gösterilmiştir.

Undergravel airlift pump is a simple filter system that uses air. The purpose of this study was to analyze the efficiency of using Undergravel Airlift Pump in Aquaculture Oreochromis sp. The approach used is an experimental approach with 2 treatments and 1 control. Analysis of the data used is the analysis of variance (ANOVA). The results showed that the application of undergravel airlift pump had an impact on water quality. The treatment of middle airlift position is more effective compared to the bottom airlift and control. The temperature and pH parameters were not significantly different; dissolved oxygen and total dissolved solid were significantly different.

Background The BLUE 400 filter system (Carl Zeiss Meditec, Oberkochen, Germany) has provided visualization of 5-ALA-induced fluorescence-guided surgery for more than 20 years. Nevertheless, constraints, e.g., limited background discrimination during hemostasis, obstruct fluency of surgery. A novel filter with improved background visualization was developed, requiring validation regarding fluorescence discrimination. The aim of this article is to determine diagnostic accuracy and perception of protoporphyrin IX (PpIX) discrimination of a novel filter system with higher background illumination (BLUE 400 AR) compared with the gold standard, BLUE 400. Methods A surgical microscope equipped with both BLUE 400 and BLUE 400 AR was used. Comparisons were performed on a biological basis and on the visual perception of margins. High-resolution images were compared during and after surgery by senior neurosurgeons. In a predefined biopsy algorithm, four biopsies per patient at tumor margins of PpIX fluorescence and adjacent brain were acquired using BLUE 400 AR only from regions intended for resection and assessed for cell count and density. Results Thirty-two patients with malignant gliomas were included in this study. BLUE 400 AR markedly enhanced the brightness of the surgical field, allowing superior discrimination of brain anatomy. A total of 128 biopsies from fluorescence margins were collected. Positive predictive value (PPV) was 98.44% (95% CI, 90.06–99.77%) for malignant glioma. Residual median cell density in non-fluorescent tissue was 13% (IQR 13 to 31). Perception of the location of fluorescent margins on HD images was equivalent for both filter combinations. Conclusions BLUE 400 AR demonstrated superior background compared with conventional BLUE 400 in malignant glioma surgery but comparable fluorescence margins and PPV. Therefore, BLUE 400 AR can be considered safe and effective in supporting malignant glioma surgery.

Penelitian ini bertujuan untuk mengetahui dan menentukan dosis karotenoid yang tepat terhadap perlakuan bioenkapsulasi karotenoid pakan Skeletonema costatum dan nauplius Artemia terhadap pertumbuhan larva ikan nila air payau (Oreochomis niloticus). Penelitian ini menggunakan metode rancangan acak lengkap dengan 4 perlakuan dosis karotenoid (0, 10, 15, 20 mg/L air media) dan masing-masing 3 ulangan. Pemeliharaan larva dilakukan selama 30 hari dalam wadah plastik berbentuk bundar dengan volume 50 L berjumlah 12 unit masing-masing dilengkapi filterisasi. Pemberian pakan Skeletonema costatum 300.000 ind/L dan nauplius artemia 500.000 ind/L dengan frekuensi pemberian pakan 2 kali sehari yaitu pada pukul 08.00 dan 17.00 WITA. Hasil penelitian menunjukkan bahwa kandungan karotenoid Skletonema costatum tertinggi yaitu 55,47 ppm terdapat pada dosis 20 mg/L, kandungan karotenoid artemia 7,181 ppm pada dosis 20 mg/L, kandungan karotenoid larva ikan nila air payau tertinggi 2,33 ppm pada dosis 15 mg/L. Laju pertumbuhan panjang dan bobot tubuh tertinggi yaitu 1,65 cm dan 0,2483 % terdapat pada perlakuan B (10 ppm). Dosis 10 - 15 mg/L karotenoid mampu diserap dan dirubah oleh larva menjadi vitamin A sehingga mampu meningkatkan laju pertumbuhan larva ikan nila air payau.

Recently, air quality issues have attracted much more attention. This paper aims to find an effective way to analyse the buildings’ effects on the air quality variation between indoor and outdoor. To do so, we treat the building as a dynamic filter system by regarding the outdoor PM $_{2.5}$ , the indoor PM $_{2.5}$ , and the building as the input, the output, and a response system, respectively. To analyze the filtering effect produced by buildings, the statistical distribution of the indoor PM $_{2.5}$ per hour is studied, and the interrelationship between the indoor and the outdoor PM $_{2.5}$ is explored in time domain. Some interesting physical laws are discovered by using the collected data. First, the indoor PM $_{2.5}$ per hour follows Gaussian distribution in most cases. Second, the indoor PM $_{2.5}$ has a positive correlation with the corresponding outdoor one. Third, a linear regression model with high accuracy on analyzing the indoor PM $_{2.5}$ is presented, which indicates that the indoor PM $_{2.5}$ consists of two parts—one comes from the outdoor PM $_{2.5}$ penetrating into the building and the other comes from the indoor environment. Fourth, by applying different system identification methods, it is found that the B–J model is the best one in characterizing the memory effects of the building for both long time and short time scales. Particularly, for the long time memory effect, the indoor PM $_{2.5}$ average memory duration (AMD) is about 2 h, and the indoor PM $_{2.5}$ AMD to the outdoor PM $_{2.5}$ is about 7 h, while for the short time memory effect, the indoor PM $_{2.5}$ AMD is also about 2 h but that to the outdoor PM $_{2.5}$ is about 5 h. Additionally, the continuance of outdoor PM $_{2.5}$ has much greater effect on the indoor one than its concentration.

Imperata cylindrica, often known as cogon grass, is a low-cost and useful sorbent for absorbing oil and optimising processes. The effects of temperature, time, packing density and oil concentration on oil absorption efficiency were investigated and optimised utilising one-factor-at-a-time (OFAT) and response surface methodology (RSM) approaches. Temperature and oil concentration are two important variables in the oil absorption process. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analysis were used to characterise cogon grass. After treatment and oil absorption, the FTIR method indicated new formation and deformation of functional groups, while SEM revealed changes in the surface and texture of cogon grass, including a roughened and jagged surface. Validation of the RSM model yielded 93.54% efficiency with 22.45 mL oil absorbed at 128 °C temperature and 36 (v/v)% oil concentration while keeping packing density and time constant at 30 min and 0.20 g/cm3, respectively. This study may provide an insight into the usefulness of a statistical approach to maximise the oil absorption of cogon grass as an oil sorbent.

Oil spill incidents are hazardous and have prolonged damage to the marine environment. Management and spill clean-up procedures are practical and rapid, with several shortcomings. Coco peat (CP) and coco fibre (CF) are refined from coconut waste, and their abundance makes them desirable for diesel spillage treatment. Using a filter-based system, the selectivity of coco peat sorbent was tested using CP, CF and peat-fibre mix (CPM). CP exhibited maximal diesel sorption capacity with minimal seawater uptake, thus being selected for further optimisation analysis. The heat treatment considerably improved the sorption capacity and efficiency of diesel absorbed by CP, as supported by FTIR and VPSEM–EDX analysis. Conventional one-factor-at-a-time (OFAT) examined the performance of diesel sorption by CP under varying parameters, namely temperature, time of heating, packing density and diesel concentration. The significant factors were statistically evaluated using response surface methodology (RSM) via Plackett–Burman design (PB) and central composite design (CCD). Three significant (p &lt, 0.05) factors (time, packing density and diesel concentration) were identified by PB and further analysed for interactions among the parameters. CCD predicted efficiency of diesel absorbed at 59.92% (71.90 mL) (initial diesel concentration of 30% v/v) and the experimental model validated the design with 59.17% (71.00 mL) diesel sorbed at the optimised conditions of 14.1 min of heating (200 °C) with packing density of 0.08 g/cm3 and 30% (v/v) of diesel concentration. The performance of CP in RSM (59.17%) was better than that in OFAT (58.33%). The discoveries imply that natural sorbent materials such as CP in oil spill clean-up operations can be advantageous and environmentally feasible. This study also demonstrated the diesel-filter system as a pilot study for the prospective up-scale application of oil spills.

We propose a set of eleven faint UV white dwarf stars as potential UV standards for the UVIT filter system on-board AstroSat mission. Synthetic photometry of these stars has been carried out using the in-orbit filter curves of UVIT, GALEX, UVOT and model spectra in the literature. The synthetic photometry of GALEX and UVOT is well correlated with their respective observations. The synthetic UVIT photometry is found to be strongly correlated with that of GALEX. The UV extinction $$A_\lambda $$ for these stars has been computed using CCM-89 extinction model and its value for the $$\lambda _{\mathrm{mean}}$$ of each UVIT filter band has been listed. These results motivate us to recommend this set of stars as additional UVIT flux calibrators.

The removal of phosphorus from wastewater is a common procedure. Improving water quality is the aim of wastewater treatment. There are many types of conventional methods that have been used for the removal of phosphorus. Phosphorus reaction with chemicals can be removed immediately from water. However, the use of chemicals often increases the cost of wastewater treatment. This study aims to investigate the physical and chemical characteristics of RCA that influence the removal of phosphorus, as well as the percentage of phosphorus removal using RCA of two different sizes namely, 5 mm to 10 mm and 25 mm to 30 mm. The samples taken from the influent and effluent filters were tested and analysed in terms of the uptake capacity of phosphorus (q) and the percentage of phosphorus removal (%). The highest percentage of phosphorus removal achieved was 99.54% in the initial concentration of 10 mg/L by RCA measuring between 5 mm to 10 mm while the lowest percentage of phosphorus removal was 66.25% in the initial concentration of 50 mg/L for RCAs measuring between 25 mm to 30 mm. Furthermore, RCA achieved the highest uptake capacity (q) of 3.45 mg/L in the initial wastewater concentration of 50 mg/L. In conclusion, RCA has the potential to remove phosphorus, particularly in low concentrations of synthetic wastewater and high pH conditions.

A coal dust scattered from storage and transfer facilities of coal power plant is led to a air pollution. It is difficult to reduce some scattered coal dust by used filter system such as bag filter and electric precipitator because of being scattered in the large area. The need to cut down coal dust generation has been increased as being reinforced regulation to reduce dust from coal power plant. So this is a experimental basic study which reduces coal dust generation. This study is to reduce scattering rate of the coal dust by collision and interception between fine fog droplet and coal dust particles. The reducing rate of coal dust is evaluated by droplet size of 10㎛ sprayed. It is evaluated that capture efficiency is lower as a coal dust concentration become higher. And also it is increase as droplet size is decrase and droplet density is increase. It is resulted that coal dust coefficient to optimize the fog system design is 25μg/m3/l/hr and capture efficiency of coal dust is about 80%.

Enteric viruses, generally found in sewage, are recognized as the main cause of waterborne and foodborne public health outbreaks. Among leading enteric viruses, the Rotavirus A (RVA) detection in wastewater appeared to be a novel approach to monitor the emergence of these viruses in some countries where the viral gastroenteritis surveillance is almost absent such as in Tunisia. The RVA detection and quantification in an industrial sewage purification plant of Charguia I (Tunis, Tunisia) were achieved to evaluate the performance of activated sludge procedures coupled to a macrofiltration monolamp ultraviolet irradiation type C (UV-C254) disinfection reactor. This UV-C254 system was preceded by a fiberglass cartridge filter system with an average porosity of 45 μm to clarify the water and thus increase its UV transmittance. A total of 140 composite sewage samples was collected from this line of treatment and analyzed for RVA detection. The detection and the viral load quantification of RVA were performed using real-time reverse transcription polymerase chain reaction (RT-PCR). The virological results showed in general that RVA were detected at high frequency of 98% (137/140). In fact, the RVA detection rates at the exit of the two studied wastewater treatment were about 100% at the exit of the activated sludge procedure. It means that all wastewater sampled at this last step of treatment was positive for RVA detection. On the other hand, 92.5% of the wastewater samples taken at the exit of the monolamp UV-C254 reactor were positive for the RVA. However, the RVA quantification results expressed as viral load showed a significant reduction in the means of RVA viral loads at the exit of the biological activated sludge procedure and the tertiary UV-C254 treatment, showing in general an improved treated wastewater virological quality. Therefore, the RVA load removal rates recorded at the two successive stages of treatment, the activated sludge and the UV-C254 treatment, were around 85% and 73%, respectively, as compared to the one with 100% registered for the raw wastewater. In addition, good physical-chemical and bacteriological qualities of the treated sewage were found at the exit of the two considered wastewater treatment procedures. The present investigation represents the first Tunisian environmental report showing the good effectiveness and performance of the biological and the tertiary treatments for RVA removal. Therefore, an improved and an optimized tertiary disinfection treatment was needed since it could be a good means for getting better viral water quality and for minimizing the transmission and dissemination of human infectious viral diseases.

With the exponential growth of network data storage scale, the issue of uniform distribution and efficient retrieval of data in the distributed storage systems such as the Redis cluster has receive...

Fairness assumptions are commonly used to filter system behaviors, thereby distinguishing between realistic and unrealistic executions. This allows for key arguments in correctness proofs of distributed systems, which would not be possible otherwise. Our first contribution is an equivalence spectrum in which fairness assumptions are preserved. Although the identified equivalences allow for reasoning about correctness incorporating fairness assumptions, this does not necessarily allow for the lifting of arguments from sequential processes to parallel compositions employing arbitrary synchronization mechanisms. Our second contribution is, therefore, an analysis of parallel composition operators and their synchronization mechanisms in this respect.

The objective of this study was to evaluate a filter system to harvest plasma to assess failure of passive transfer (FPT) in newborn calves. Blood samples (n = 227) for serum and plasma harvesting were collected via jugular vein puncture from Holstein calves aged 1 to 7 d from 4 commercial dairy herds in Northeast Germany. Serum IgG concentrations were determined using a sandwich ELISA. Failure of passive transfer was defined as IgG concentrations10 mg/mL and used as a gold standard. One handheld optical refractometer (Euromex Holland, Arnhem, the Netherlands) and 2 digital Brix refractometers (device 1: HI 96801 digital refractometer, Hanna Instruments, Woonsocket, RI; device 2: Misco PA201, Misco, Solon, OH) were used to analyze total proteins in serum or plasma. The colostrum uptake of the calf can thus be monitored and calves with FPT can be identified. Serum was obtained through centrifugation. Plasma was obtained through either a filter system or centrifugation. For plasma filtration, approximately 2 mL of lithium heparin blood was injected into the inlet reservoir of a plasma filter (2-Drop-Filter, Pharmadoc, Lübeck, Germany) using a disposable syringe. Receiver operating characteristic curve analyses were used to determine optimum thresholds for each of the 3 devices using different media. Sixty-seven (30%) calves had FPT. For the handheld optical refractometer, the optimum threshold was 5.6 g/dL [sensitivity 70.1%; specificity 80.0%; positive predictive value (PPV) 60.1%; negative predictive value (NPV) 86.2%; area under the curve (AUC) 0.85] using serum. For centrifuged plasma, the optimum threshold was 6.3 g/dL (sensitivity 82.1%; specificity 68.1%; PPV 52.5%; NPV 89.9%; AUC 0.84), and for filtered plasma, the threshold was 6.0 g/dL (sensitivity 56.7%; specificity 90.0%; PPV 70.9%; NPV 82.9%; AUC 0.80). For device 1, the optimum threshold was 8.9% Brix (sensitivity 82.1%; specificity 63.8%; PPV 48.7%; NPV 89.5%; AUC 0.81), 9.4% Brix (sensitivity 76.1%; specificity 73.7%; PPV 55.4%; NPV 87.8%; AUC 0.80), using serum and centrifuged plasma, respectively. For device 2, the optimum threshold was 8.7% Brix (sensitivity 74.6%; specificity 76.2%; PPV 57.4%; NPV 87.5%; AUC 0.83), 9.5% Brix (sensitivity 80.6%; specificity 70.6%; PPV 54.0%; NPV 89.5%; AUC 0.83), and 9.2% Brix (sensitivity 58.2%; specificity 87.5%; PPV 66.6%; NPV 83.0%; AUC 0.80) using serum, centrifuged plasma, and filtered plasma, respectively. Based on the AUC, the 3 devices yielded comparable test characteristics to identify calves with FPT. In conclusion, a filter system can be used to facilitate the evaluation of FPT as a point of care technique in calves without the need for serum centrifugation.

Stomata, specialized functional openings distributed on the leaf surface, are used for plant respiration by allowing gas exchange, i.e., taking in carbon dioxide and releasing oxygen, and for water content regulation. Their function is vital to plant survival. Leaves with different wettability exhibit different stomata densities. In this study, we find that stomata on Pistia stratiotes L. leaves are protected by superhydrophobic setae, which prevent direct contact between the stomata and water in humid environments by suspending water droplets on the top of the setae. Thus, oxygen and carbon dioxide are freely exchanged through the stomata. This structure inspired us to design and develop a mask for filtering solid particles and noxious gas from the atmosphere. The incoming gas is in convective contact with water, achieving a filtering efficiency. The solid particles and potential harmful gas in air are wetted and captured by water, leaving fresh air for healthy breathing. This novel design has potential applications in the treatment of respiratory diseases.

BACKGROUND Fluorescence-guided resections using 5-aminolevulinic acid (5-ALA)-induced tumor porphyrins have been established as an adjunct for malignant glioma surgery based on a phase III study using specifically adapted microscopes for visualizing fluorescing protoporphyrin IX (PPIX). New hardware technologies are being introduced, which claim the same performance as the original technology for visualizing fluorescence. This assumes that qualitative fluorescence detection is equivalent to the established standard, an assumption that needs to be critically assessed. OBJECTIVE To determine PPIX concentrations (cPPIX) in tissue that can be detected visually using the established BLUE400 filter system (Carl Zeiss Meditec, Oberkochen, Germany) as a basis for defining the performance of this system. METHODS Utilizing a hyperspectral imaging system, tumor samples from patients harboring different tumor tissues, with or without visible fluorescence, were analyzed. Absolute values of cPPIX were calculated after calibrating the system with fluorescence phantoms with known cPPIX. RESULTS A total of 524 tumor samples from 162 patients were analyzed. Visual fluorescence under the BLUE400 filter was documented by experienced neurosurgeons. A 0.9 μg/ml threshold of cPPIX was defined as the minimal concentration required to detect and discriminate visual fluorescence. CONCLUSION This is the first report providing data on the threshold of cPPIX, which is visually detected using the current generation of microscopes, thus defining the specificity and sensitivity of this technology as initially tested in a randomized trial. Novel technologies should show similar characteristics in order to be used safely and effectively. If more sensitive, such technologies require further assessments of tumor selectivity.