A framework for the systematic evaluation of a novel cigarette filter technology

Any functional change in cigarette filter design warrants a rigorous assessment to ensure comparability to existing filter functionality. This study compares the functionality of a standard CA filter with a novel cellulose-based alternative using a combination of emissions, in silico approaches, pre-clinical assessments and behavioural studies. We assess the challenges faced with a significant filtration change, the substantiation of this change and the limitations of such assessments. We explore cigarette emission chemical profiles; assess the potential toxicological impacts (in vitro and statistical modelling) of the differing chemical profiles of cigarette smoke aerosol resulting from the respective filter types; and, finally investigate the behavioural aspects associated with use of the novel filter as compared to the traditional one. The aim of the study was to establish a weight of evidence assessment framework for the comprehensive evaluation of a novel cigarette filter design as part of robust stewardship approach. The data show comparability to a standard CA filter across all assessments and highlight potential areas of investigation for future novel filter product iterations. The approach demonstrates the applicability of a comprehensive step-wise assessment framework to identify any potential increased toxicant emissions and exposures associated with using the novel filter.

Green-engineered clay- and carbon-based composite materials for the adsorption of benzene from air

Benzene is a carcinogenic volatile organic compound (VOC) that is ubiquitously detected in enclosed spaces due to emissions from cooking activities, building materials, and cleaning products. To remove benzene and other VOCs from indoor air and protect public health, traditional fabric filters have been modified to contain activated carbons to enhance the filtration efficacy. In this study, composites derived from natural clay minerals and activated carbon were individually green-engineered with chlorophylls and were attached to the surface of filter materials. These systems were assessed for their adsorption of benzene from air using in vitro and in silico methods. Isothermal, thermodynamic, and kinetic experiments indicated that all green-engineered composites had improved binding profiles for benzene, as demonstrated by increased binding affinities (Kf ≥ 900 vs 472) and lower values of Gibbs free energy (ΔG = -16.8 vs -15.2) compared to activated carbon. Adsorption of benzene to all composites was achieved quickly (< 30 min), and the green-engineered composites also showed low levels of desorption (≤ 25%). While free chlorophyll is known to be photosensitive, chlorophylls in the green-engineered composites showed photostability and maintained high binding rates (≥ 70%). Additionally, the in silico simulations demonstrated the significant contribution of chlorophyll for the overall binding of benzene in clay systems and that chlorophyll could contribute to benzene binding in the carbon-based systems. Together, these studies indicated that novel, green-engineered composite materials can be effective filter sorbents to enhance the removal of benzene from air.

Filters of automobile air conditioning systems as in-car source of exposure to infections and toxic moulds

The main component of an air conditioning system is air filters. Over time, the filters of an air conditioning system in cars can turn into sources of emission of microbiological hazards. The aim of this study was to quantitatively and qualitatively assess the presence of infectious and toxic fungi in the AC filters in passenger cars. The studied non-woven filters were removed from passenger cars during the "winter"/"summer" seasons. The taxonomic identification of the fungi isolated from the filters was performed using both the culture-based and molecular methods. RT-PCR was applied to assess the presence of gene fragments regulating aflatoxin biosynthesis in the isolates obtained from fungal cultures. The average fungal concentrations in the filter samples collected during the summer/winter season were 5.4 × 104 cfu/m2 and 2.4 × 104 cfu/m2, respectively. Most of the filter samples, collected in both the studied seasons, revealed the presence of Aspergillus species including A. fumigatus, A. niger, A. terreus and/or A. flavus. The recorded levels of fungal contamination of AC filters in passenger cars indicate the necessity for more frequent filter replacement in this type of vehicle. Occupational exposure to moulds and the resulting health problems that may be experienced by professional drivers should be properly recognised in order to undertake effective preventive measures.

Spectrophotometric Analysis of Different Polymethyl Methacrylate Filters and their Importance in the Implantation of Corneal Rings

PURPOSE

This study evaluated the luminous behavior applied to materials used in intraocular surgeries.

METHODS

Discs of the different products were delivered in 19.00 mm × 3.00 mm. Each sample was fixed on support keeping it perpendicular to the spectrophotometer beam. Later, their analyses were carried out in the air/PMMA ratio. The graphs of individual profiles of the measurements along the length were constructed according to each of the filters from the spectrophotometric analysis. In addition, descriptive statistics of transmittance and absorbance for each wavelength presented were correlated for each filter.

RESULTS

It is possible to observe that the minimum absorption measure was found in the Red Filter, especially in the blue and green light spectrum.

CONCLUSION

Using filters in PMMA materials appears to improve visual quality in corneal implants, especially the red filter, due to greater absorbance of light leading to fewer light scattering phenomena through corneal rings. However, further studies comparing the effects of different filters on Intracorneal rings should be carried out to elucidate this field of study.

Mitigation of Respirable Aerosol Particles from Speech and Language Therapy Exercises

INTRODUCTION

Phonation and speech are known sources of respirable aerosol in humans. Voice assessment and treatment manipulate all the subsystems of voice production, and previous work (Saccente-Kennedy et al., 2022) has demonstrated such activities can generate >10 times more aerosol than conversational speech and 30 times more aerosol than breathing. Aspects of voice therapy may therefore be considered aerosol generating procedures and pose a greater risk of potential airborne pathogen (eg, SARS-CoV-2) transmission than typical speech. Effective mitigation measures may be required to ensure safe service delivery for therapist and patient.

OBJECTIVE

To assess the effectiveness of mitigation measures in reducing detectable respirable aerosol produced by voice assessment/therapy.

METHODS

We recruited 15 healthy participants (8 cis-males, 7 cis-females), 9 of whom were voice-specialist speech-language pathologists. Optical Particle Sizers (OPS) (Model 3330, TSI) were used to measure the number concentration of respirable aerosol particles (0.3 µm-10 µm) generated during a selection of voice assessment/therapy tasks, both with and without mitigation measures in place. Measurements were performed in a laminar flow operating theatre, with near-zero background aerosol concentration, allowing us to quantify the number concentration of respiratory aerosol particles produced. Mitigation measures included the wearing of Type IIR fluid resistant surgical masks, wrapping the same masks around the end of straws, and the use of heat and moisture exchange microbiological filters (HMEFs) for a water resistance therapy (WRT) task.

RESULTS

All unmitigated therapy tasks produced more aerosol than unmasked breathing or speaking. Mitigation strategies reduced detectable aerosol from all tasks to a level significantly below, or no different to, that of unmasked breathing. Pooled filtration efficiencies determined that Type IIR surgical masks reduced detectable aerosol by 90%. Surgical masks wrapped around straws reduced detectable aerosol by 96%. HMEF filters were 100% effective in mitigating the aerosol from WRT, the exercise that generated more aerosol than any other task in the unmitigated condition.

CONCLUSIONS

Voice therapy and assessment causes the release of significant quantities of respirable aerosol. However, simple mitigation strategies can reduce emitted aerosol concentrations to levels comparable to unmasked breathing.

The effect of filters and varying illumination on contrast sensitivity in eyes with moderate to severe visual impairment

PURPOSE

To investigate the effect of filters and illumination on contrast sensitivity in persons with cataract, pseudophakia, maculopathy and glaucoma to provide a guide for eye care providers in low vision rehabilitation.

MATERIALS AND METHODS

A within-subjects experimental design with a counter-balanced presentation technique was employed in this study. The contrast sensitivity of eyes with cataract, pseudophakia, maculopathy and glaucoma was measured with filters (no filter, yellow, pink and orange) combined with increasing illumination levels (100 lx, 300 lx, 700 lx and 1000 lx) using the SpotChecks™ contrast sensitivity chart. The data were analyzed using descriptive statistics and two-way repeated measures ANOVA.

RESULTS

The yellow filter at 100 lx significantly improved contrast sensitivity in the maculopathy group. There were no significant improvements with either intervention in the rest of the groups. There was, however, a significant interaction between filters and illumination in the cataract group.

CONCLUSION

There were small improvements in contrast sensitivity at low illumination levels with the yellow filter in the maculopathy group, and this could be considered in clinical practice and low vision rehabilitation. Overall, filters at most illumination levels did not benefit most groups.

A feature selection method based on graph theory for cancer classification

OBJECTIVE

Gene expression profile data is a good data source for people to study tumors, but gene expression data has the characteristics of high dimension and redundancy. Therefore, gene selection is a very important step in microarray data classification.

METHOD

In this paper, a feature selection method based on the maximum mutual information coefficient and graph theory is proposed. Each feature of gene expression data is treated as a vertex of the graph, and the maximum mutual information coefficient between genes is used to measure the relationship between the vertices to construct an undirected graph, and then the core and coritivity theory is used to determine the feature subset of gene data.

RESULTS

In this work, we used three different classification models and three different evaluation metrics such as accuracy, F1-Score, and AUC to evaluate the classification performance to avoid reliance on any one classifier or evaluation metric. The experimental results on six different types of genetic data show that our proposed algorithm has high accuracy and robustness compared to other advanced feature selection methods.

CONCLUSION

In this method, the importance and correlation of features are considered at the same time, and the problem of gene selection in microarray data classification is solved.

The impact of digital filters on the diagnosis of simulated root resorptions in digital radiographic systems

OBJECTIVES

To evaluate the influence of digital filters of intraoral radiographic systems on the diagnosis of simulated internal and external root resorptions and image quality.

MATERIALS AND METHODS

Internal root resorption (IRR) and external root resorption (ERR) were simulated in 34 teeth. For image acquisition, two radiographic systems were used: Digora Toto and VistaScan. All filters available in these systems were applied. Three observers scored the detection of root resorptions in a 5-point scale. The noise and the contrast-to-noise ratio (CNR) were calculated. The area under ROC curve, sensitivity, specificity, and accuracy were obtained. One-way ANOVA with Tukey's post hoc tests compared the diagnostic values, noise, and CNR between the filters (α = 0.05).

RESULTS

For ERR, there were no significant differences in diagnostic values between the filters tested for both systems. For IRR, Original and Noise Reduction filters presented higher sensitivity than the Sharpen2 filter for images from Digora Toto, with no differences between the other groups. For VistaScan, there were no significant differences of diagnostic values between the groups studied. Noise values differed among the filters of both systems. The CNR of the filters differed only for the bone region for Digora Toto, while for VistaScan, both tooth and bone regions differed.

CONCLUSIONS

Despite promoting changes in pixel intensities and affecting the noise level of the radiographic images, the digital filters of Digora Toto and VistaScan systems do not affect the diagnosis of internal or external root resorptions.

CLINICAL RELEVANCE

Digital filters are common tools in digital radiographic systems and may be used by the professional without impairment in root resorptions diagnosis.

Efficient capture of airborne PM by nanotubular conjugated microporous polymers based filters under harsh conditions

The exploitation of high-performance filters which can capture and remove airborne particulate matter (PM) in harsh conditions is greatly important to limit the serious effect of PM on human health. Herein, we demonstrate a simple approach for the creation of robust and hierarchically porous filters based on conjugated microporous polymers (CMPs) nanotubes for efficient PM capture. Taking advantage of their inherently superhydrophobic wettability, the CMPs-based filters possess high filtration efficiency of higher than 99.4% for PM_0.3 and 99.9% for PM_2.5 and PM₁₀, respectively, even in high humidity environment (RH ≥ 94%). The CMPs-based filters show highly physicochemical and thermal stability, e.g., by calcination at 500 °C for 2 h, the filtration efficiency of the samples still reaches as great as 99.4% for both PM_2.5 and PM₁₀ with a low-pressure drop of only 10 Pa. In addition, these CMPs-based filters can be easily regenerated and their high PM filtration efficiency remains nearly unchanged by a simple methanol washing. More interestingly, the CMPs-based filters also exhibit superior antibacterial performance, which enables them to sterilize or eliminate the bacteria possibly loaded on PM pollutions, thus showing great potential for various applications such as PM removal, air purification and so on.

Feature selection methods on gene expression microarray data for cancer classification: A systematic review

This systematic review provides researchers interested in feature selection (FS) for processing microarray data with comprehensive information about the main research directions for gene expression classification conducted during the recent seven years. A set of 132 researches published by three different publishers is reviewed. The studied papers are categorized into nine directions based on their objectives. The FS directions that received various levels of attention were then summarized. The review revealed that 'propose hybrid FS methods' represented the most interesting research direction with a percentage of 34.9%, while the other directions have lower percentages that ranged from 13.6% down to 3%. This guides researchers to select the most competitive research direction. Papers in each category are thoroughly reviewed based on six perspectives, mainly: method(s), classifier(s), dataset(s), dataset dimension(s) range, performance metric(s), and result(s) achieved.

Directly Filtering the Sparse-View CT Images by BM3D

The x-ray Computed Tomography (CT) images with sparse-view data acquisition contain severe angular aliasing artifacts. The common denoising filters do not work well if they are used to reduce the artifacts. The state-of-the-art methods to process the sparse-view CT images are deep-learning based; they require a large amount of training data pairs. This paper considers a situation where no clinical training data sets are available. All we have is one sparse scan of a patient. This paper attempts to use a BM3D filter to reduce the artifacts by using an artifact power spectral density function, which is calculated with computer simulations. The results in this paper show that the proposed method is promising in computer simulations. The proposed method has been applied to patient data, and we observe that the sparse-view artifacts are reduced, especially in the central region of the image, but the artifact reduction is not as effective at the peripheral if the control parameter in the BM3D filter is not properly chosen.

Effects of different pairing configurations of woodchips and steel chips in dual media treatment systems on nutrient removal and organics and iron leaching

Nitrogen and phosphorus are two primary nutrients that can promote eutrophication in aquatic ecosystems. Recycled steel chips have been proposed to be used in conjunction with woodchips in dual-media treatment systems to remove nutrients from water, but the effects of different pairing configurations of woodchips and steel chips on nutrient removal have not been fully understood. The use of woodchips and steel chips for water treatment can result in leaching of organic carbon and iron. However, little is known about the impact of different media configurations on organics and iron leaching. In this study, laboratory column reactors using woodchips and steel chips (volumetric ratio of 11:1) were constructed based on three pairing configurations: woodchips/steel chips, steel chips/woodchips, and mixture of the two media. The column reactors were operated to evaluate nitrate and phosphate removal efficiencies and organic carbon and iron leaching from different media pairing arrangements. The results showed that the three media pairing configurations achieved similar overall nitrate and phosphate removal efficiencies but resulted in substantially different organic carbon and iron concentrations in reactor effluents. Steel chips, when placed downstream of woodchips reduced reactor organic carbon leaching, whereas woodchips, when placed downstream of steel chips reduced reactor iron leaching. The mixed media reactor was able to effectively control both organic carbon and iron leaching. The results of flow and temperature variation experiments showed that phosphate removal efficiencies by the steel chip filter were much less affected by flow and temperature changes than nitrate removal efficiencies by the woodchip bioreactor.

Beam port filters in a TRIGA MARK III nuclear reactor to produce epithermal neutrons for BNCT

Glioblastoma multiforme is the most common and aggressive brain tumor and it is difficult to treat with conventional surgery, chemotherapy, or radiation therapy. An alternative treatment is boron neutron capture therapy which requires an energy modulated beam of neutrons and a¹⁰B drug capable of adhering to the tumor. In this work, MCNP6 Monte Carlo code was used to evaluate the effect on the neutron spectrum by placing two filters along the radial beam tube of the TRIGA Mark III nuclear reactor of ININ in Mexico. Every filter was made with the same amount and type of materials: Steel and Graphite for filter 1 and Cadmium, Aluminum, and Cadmium (Cd + Al + Cd) for filter 2. Two cases were analyzed for each filter as follows: Case A for filter 1 was considering 30 cm of steel and 30 cm of graphite, while for case B, the dimensions of filter 1 were 15 cm of steel, 15 cm of graphite, 15 cm of steel and 15 cm of graphite. Cases A and B for filter 2 were analyzed considering the same dimensions and amount of materials. The work was in the aim to produce epithermal neutrons for boron neutron capture therapy. Neutron spectra were calculated at three sites along the beam tube and two sites outside the beam tube; here, the ambient dose equivalent, the personal dose equivalent, and the effective doses were also estimated. At a distance of 517 cm of core, in case B, results in an epithermal-to-thermal neutron fluence ratio of 30.39 was obtained being larger than the one recommended by the IAEA of 20.

Perceptions About the Impact of Cigarette Filters on the Environment and Smoking-Related Behaviors

PURPOSE

Examine adolescents' and young adults' (AYAs) knowledge and perceptions about the composition and environmental harms of cigarette filters and determine how perceptions are associated with support for policy interventions.

METHODS

Cross-sectional, convenience sample from 10 California schools. AYAs (N = 429; 70% < 21 years) were surveyed about tobacco use, perceptions of cigarette filters, their impact on the environment, and cigarette sales bans.

RESULTS

Most agreed that filters are harmful to the environment and not biodegradable (89%, n = 383 respectively); fewer knew filters are made of plastic (43%, n = 185). AYAs who agreed that filters are harmful to the environment were more supportive of cigarette sales bans (OR = 2.78 [95% CI: 1.18, 6.58]).

CONCLUSIONS

Knowledge of the environmental harms of cigarettes among AYAs may strengthen support for tobacco control. More research is needed to further understand the knowledge and attitudes about the environmental impact of tobacco and to clarify how this might add support for tobacco-related policies.

LigGrep: a tool for filtering docked poses to improve virtual-screening hit rates

Structure-based virtual screening (VS) uses computer docking to prioritize candidate small-molecule ligands for subsequent experimental testing. Docking programs evaluate molecular binding in part by predicting the geometry with which a given compound might bind a target receptor (e.g., the docked "pose" relative to a protein target). Candidate ligands predicted to participate in the same intermolecular interactions typical of known ligands (or ligands that bind related proteins) are arguably more likely to be true binders. Some docking programs allow users to apply constraints during the docking process with the goal of prioritizing these critical interactions. But these programs often have restrictive and/or expensive licenses, and many popular open-source docking programs (e.g., AutoDock Vina) lack this important functionality. We present LigGrep, a free, open-source program that addresses this limitation. As input, LigGrep accepts a protein receptor file, a directory containing many docked-compound files, and a list of user-specified filters describing critical receptor/ligand interactions. LigGrep evaluates each docked pose and outputs the names of the compounds with poses that pass all filters. To demonstrate utility, we show that LigGrep can improve the hit rates of test VS targeting H. sapiens poly(ADPribose) polymerase 1 (HsPARP1), H. sapiens peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (HsPin1p), and S. cerevisiae hexokinase-2 (ScHxk2p). We hope that LigGrep will be a useful tool for the computational biology community. A copy is available free of charge at http://durrantlab.com/liggrep/ .

Out-of-focus brain image detection in serial tissue sections

BACKGROUND

A large part of image processing workflow in brain imaging is quality control which is typically done visually. One of the most time consuming steps of the quality control process is classifying an image as in-focus or out-of-focus (OOF).

NEW METHOD

In this paper we introduce an automated way of identifying OOF brain images from serial tissue sections in large datasets (>1.5 PB). The method utilizes steerable filters (STF) to derive a focus value (FV) for each image. The FV combined with an outlier detection that applies a dynamic threshold allows for the focus classification of the images.

RESULTS

The method was tested by comparing the results of our algorithm with a visual inspection of the same images. The results support that the method works extremely well by successfully identifying OOF images within serial tissue sections with a minimal number of false positives.

COMPARISON WITH EXISTING METHODS

Our algorithm was also compared to other methods and metrics and successfully tested in different stacks of images consisting solely of simulated OOF images in order to demonstrate the applicability of the method to other large datasets.

CONCLUSIONS

We have presented a practical method to distinguish OOF images from large datasets that include serial tissue sections that can be included in an automated pre-processing image analysis pipeline.

Can indoor sports centers be allowed to re-open during the COVID-19 pandemic based on a certificate of equivalence?

Within a time span of only a few months, the SARS-CoV-2 virus has managed to spread across the world. This virus can spread by close contact, which includes large droplet spray and inhalation of microscopic droplets, and by indirect contact via contaminated objects. While in most countries, supermarkets have remained open, due to the COVID-19 pandemic, authorities have ordered many other shops, restaurants, bars, music theaters and indoor sports centers to be closed. As part of COVID-19 (semi)lock-down exit strategies, many government authorities are now (May-June 2020) allowing a gradual re-opening, where sometimes indoor sport centers are last in line to be permitted to re-open. This technical note discusses the challenges in safely re-opening these facilities and the measures already suggested by others to partly tackle these challenges. It also elaborates three potential additional measures and based on these additional measures, it suggests the concept of a certificate of equivalence that could allow indoor sports centers with such a certificate to re-open safely and more rapidly. It also attempts to stimulate increased preparedness of indoor sports centers that should allow them to remain open safely during potential next waves of SARS-CoV-2 as well as future pandemics. It is concluded that fighting situations such as the COVID-19 pandemic and limiting economic damage requires increased collaboration and research by virologists, epidemiologists, microbiologists, aerosol scientists, building physicists, building services engineers and sports scientists.

Standards of instrumentation of EMG

Standardization of Electromyography (EMG) instrumentation is of particular importance to ensure high quality recordings. This consensus report on "Standards of Instrumentation of EMG" is an update and extension of the earlier IFCN Guidelines published in 1999. First, a panel of experts in different fields from different geographical distributions was invited to submit a section on their particular interest and expertise. Then, the merged document was circulated for comments and edits until a consensus emerged. The first sections in this document cover technical aspects such as instrumentation, EMG hardware and software including amplifiers and filters, digital signal analysis and instrumentation settings. Other sections cover the topics such as temporary storage, trigger and delay line, averaging, electrode types, stimulation techniques for optimal and standardised EMG examinations, and the artefacts electromyographers may face and safety rules they should follow. Finally, storage of data and databases, report generators and external communication are summarized.

Effects of aerators, filters and chlorination on contamination of water samples: a nine years study in a Southern University Hospital

OBJECTIVES

The aim of our study was to evaluate the microbiological contamination by Pseudomonas aeruginosa in the water system of the University Hospital "G. Martino" in Messina over a period of nine years, in order to a) clarify possible relationship between the presence of aerators and contamination, b) to highlight the presence of a yearly variation and c) to verify the statistical difference between microbiological contamination of taps with and without filters.

MATERIAL AND METHODS

We carried out our study between January 2010 and December 2018 through the collection of water samples that were analysed for total bacteria count and Pseudomonas aeruginosa. The differences between the results recorded over the nine-year study period were evaluated using variance analysis. P values of <0.05 were considered statistically significant. Software R was used for statistical assessment.

RESULTS

We analysed a total of 6168 samples with a positive rate of 9.31% and a decreasing trend over the years to a value of 2.44% (p<0.001), due to the elimination of the aerators of taps without filters and also to the introduction of filters in taps of high-risk wards and surgical rooms. We found statistical difference between taps with or without filter (p<0.001) and a higher positive rate during the summer season compared to the other months.

CONCLUSIONS

These results reveal a high level of contamination of taps by opportunistic bacteria with severe implications especially for high-risk settings and therefore, the need to improve the management of these devices.

Visual training could be useful for improving reading capabilities in dyslexia

The term dyslexia originated in 1887 when an ophthalmologist described the difficulty of learning to read. After more than a century of research, we still do not know the etiology of such pathology. Several hypotheses have been suggested to explain dyslexia and in the present article we will describe in detail the visual attentional deficits reported in dyslexia. Reading is a complex cognitive process during which several mechanisms are involved (visual perception, eye movements -saccades and fixations-, semantic and linguistic abilities); consequently, a deficit in one of these different components could cause impairment in reading acquisition. In children with dyslexia, we observed abnormal oculomotor patterns during reading: frequent saccades of small amplitude, long-term fixation, high number of saccades to the left (retro-saccades), and poor binocular coordination during and after the saccades. These results suggest a deficit of visual information processing as well as an immaturity of the interaction between the saccade and vergence systems. In the present review, we will discuss different methods that use short periods of visual rehabilitation or text manipulation, and by using an eye tracker in order to obtain objective information on eye movement's performance during reading, assist in improved reading performance of dyslexic children.

Effect of earthworms and plants on the efficiency of vertical flow systems treating university wastewater

One of the possible ways to improve the operation efficiency of constructed wetlands and to prevent their clogging is the application of earthworms. They have already been successfully applied for vermicomposting and for sludge dewatering and treatment. A few studies have already examined the effect of earthworms on the treatment of wastewater by vertical flow constructed wetlands (VFCWs), but none of them have provided a yearlong research result from an open-air system or compared the effect that different seasons in a temperate climate area can have on these invertebrates. The goal of this research was to estimate the effect that earthworms and plants have on VFCW's operation. Four mesocosms (a filter, a filter with earthworms, a VFCW and a VFCW with earthworms) were built and their influent and effluent water quality was monitored for a period of 1 year. They were fed with wastewater coming from a building of the University of Bologna (Italy). The results have shown that the presence of earthworms in this specific system did not reduce the organic matter content of the substrate, but it has positively influenced plants' growth. However, since neither earthworms nor plants had a statistically significant effect on the effluent quality, it can be concluded that the integration of these invertebrates cannot improve wastewater treatment of vertical flow filters or constructed wetlands.

Non-Linear Filtering Technique Used for Testing the Human Lumbar Spine FEA Model

In this paper, the objective is to generate a mesh model of a spine that simulates numerically the biomedical properties of two vertebrae (L4 and L5) of human spine and an inter vertebrae disc using Finite Element Analysis (FEA) technique. Here, different types of non-linear filters and different edge detection techniques are used to segment the edges and the results are compared. The result shows that median filter obtains improved segmented output results in terms of edge length density, average magnitude, final threshold, initial position, and fine-tuned image. The behaviour of spine FEA model is analysed in terms of various parameters like equivalent elastic strain, total deformation, maximum principal elastic strain, minimum principal elastic strain, shear elastic strain, normal elastic strain, and minimum and maximum principal stress, equivalent stress, shear stress and normal stress. These parameters are used to analyse the human spine model under different conditions and different angles using ANSYS simulation tool. Further, MATLAB is carried out to implement various filters and edge detectors on proposed spine model.

Removal of emerging contaminants from wastewater through pilot plants using intermittent sand/coke filters for its subsequent reuse

Effluents from wastewater treatment plants (WWTPs) are widely recognized as the main source of emerging contaminants (stimulants and antibiotics). In this study, intermittent sand and/or coke filters were installed as a tertiary treatment at the outlet of a secondary settling tank at the WWTP in Medina Sidonia, Spain. Regular sampling followed by solid-phase extraction (SPE) and analysis by liquid chromatography-mass spectrometry (UPLC-MS) showed the complete removal of the concentrations of the emerging contaminants (caffeine, theobromine, theophylline, amoxicillin and penicillin G). Moreover, optimal filtration conditions for the reuse of treated water were presented.

Simple synthesis and characterization of l-Cystine functionalized δ-FeOOH for highly efficient Hg(II) removal from contamined water and mining waste

l-Cystine functionalized δ-FeOOH nanoparticles (Cys-δ-FeOOH) were prepared by a cheap and straightforward method for using as an adsorbent of Hg(II) in aqueous solution. X-ray diffraction (XRD), attenuated total reflectance infrared spectroscopy (ATR-IR), and Raman spectroscopy confirmed that Cys-δ-FeOOH was successfully synthesized. Cys-δ-FeOOH with 14 nm crystal size, 34 m² g^-1 surface area, and 9 nm pore size were produced. The functionalization of the δ-FeOOH surface with cysteine decreases the point of zero charge of the iron oxyhydroxide from 8.4 in δ-FeOOH to 5.7 in Cys-δ-FeOOH, which is beneficial for the adsorption of Hg(II) near neutral pH. The maximum Hg(II) adsorption capacity of the δ-FeOOH and Cys-δ-FeOOH at pH 7 were found to be 35 mg g^-1 and 217 mg g^-1, respectively. The kinetics data were best fitted by a pseudo-second-order model, suggesting chemical adsorption on the surface and pores of Cys-δ-FeOOH nanoparticles. Finally, δ-FeOOH and Cys-δ-FeOOH filters were constructed for purifying mercury-contaminated water. The filters were highly efficient to treat mercury-contaminated water from a Brazilian river, reducing the concentration of mercury in water to values below the allowed limits by the current legislation.

Filtering of neurophysiologic signals

Clinical neurophysiologic signals cover a broad range of frequencies. Filters help to emphasize waveforms that are of clinical or research interest and to mold their frequency characteristics to suit the purpose of the investigation. Some frequency content is obvious and well known, such as the alpha rhythm (8-11Hz) or spindles (12-14Hz) in the EEG. Other frequencies are not initially discriminable from background activity and require filtering in order to examine them, such as high-frequency oscillations (80-500Hz) in EEG and brainstem auditory evoked potentials (100-3000Hz). Often used to mitigate the effects of background noise or artifact, filters can be used specifically to attenuate unwanted frequencies, such as mains interference (50 or 60Hz) and electrode offset potential (<0.1Hz). For digital instrumentation, an antialiasing filter (below Nyquist) is always needed prior to sampling by the analog-to-digital converter. Once the signals are in the digital realm, sophisticated filtering operations can be carried out post hoc; but in order not to be misled, the neurophysiologist must always bear in mind the effect of filtering on the physiological waveform.

Instrumentation for electrodiagnostic studies

The instrument and accessories are an important part of the electrodiagnostic (EDX) testing. Their functional understanding is useful to recognize and reduce various artifacts and noise/interference in the signal. In this review, we will describe the technical specifications of various components of the instrument, and their effect on signals and noise. This will be illustrated using example of electromyography and nerve conduction studies. However the same principles also apply to other modalities of testing. We will also provide general strategies to reduce noise and artifacts, followed by some modality specific examples.

Phthalates and organophosphates in settled dust and HVAC filter dust of U.S. low-income homes: Association with season, building characteristics, and childhood asthma

Phthalates and organophosphates are ubiquitous indoor semi-volatile organic contaminants (SVOCs) that have been widely used as plasticizers and flame retardants in consumer products. Although many studies have assessed their levels in house dust, only a few used dust samples captured by filters of building heating, ventilation, and air conditioning (HVAC) systems. HVAC filters collect particles from large volumes of air over a long period of time (potentially known) and thus provide a spatially and temporally integrated concentration. This study measured concentrations of phthalates and organophosphates in HVAC filter dust and settled floor dust collected from low-income homes in Texas, United States, in both the summer and winter seasons. The most frequently detected compounds were benzyl butyl phthalate (BBzP), di-(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate (DnOP), tris (1-chloro-2-propyl) phosphate (TCIPP), triphenyl phosphate (TPHP), and tris (1,3-dichloroisopropyl) phosphate (TDCIPP). The median level of TCIPP in settled dust was 3- to 180-times higher than levels reported in other studies of residential homes. Significantly higher concentrations were observed in HVAC filter dust as compared to settled dust for most of the frequently detected compounds in both seasons, except for several phthalates in the winter. SVOC concentrations in settled dust in winter were generally higher than in summer, while different seasonality patterns were found for HVAC filter dust. Settled dust samples from homes with vinyl flooring contained significantly higher levels of BBzP and DEHP as compared to homes with other types of floor material. The concentration of DEHP and TDCIPP in settled dust also significantly associated with the presence of carpet in homes. Cleaning activities to remove dust from furniture actually increased the levels of certain compounds in HVAC filter dust, while frequent vacuuming of carpet helped to decrease the concentrations of some compounds in settled dust. Additionally, the size and age of a given house also correlated with the levels of some pollutants in dust. A statistically significant association between DEHP concentration in HVAC filter dust in summer and the severity of asthma in children was observed. These results suggest that HVAC filter dust represents a useful sampling medium to monitor indoor SVOC concentrations with high sensitivity; in contrast, when using settled dust, in addition to consideration of seasonal influences, it is critical to know the sampling location because the type and level of SVOCs may be related to local materials used there.

Clinical implications of intravenous drug incompatibilities in critically ill patients

OBJECTIVE

The aim of this review is to analyse the clinical consequences of intravenous drug incompatibilities in critically ill patients, especially the incidence of organ dysfunctions and mortality.

METHODS

A review of literature was conducted according to the PRISMA statement in June 2017, using Medline, ISI Web of Science and Clinicaltrials.gov.

DATA EXTRACTION

Eligible studies were case reports and randomised controlled trials (RCTs) that assessed the effects of drug incompatibilities in critically ill patients on morbidity or mortality as primary or secondary outcomes, or adverse events. Two investigators independently reviewed the eligibility of the study from abstracts or manuscript data.

DATA SYNTHESIS

Twelve articles met the selection criteria. The six articles reporting RCTs concern only four RCTs. RCTs were single-centre studies comparing infusion with or without filter. One of them included adult patients. The others included paediatric and neonatal intensive care unit patients. Primary endpoints were SIRS, organ failure, overall complication rate, bacteraemia, sepsis, phlebitis and length of stay. The results are mixed with one RCT reporting a reduction in SIRS, organ failure and overall complication rate, two studies in disagreement over the occurrence of sepsis and one study reporting no impact on length of hospital stay. The six articles on case reports show different drug incompatibility situations. They report pulmonary toxicity.

CONCLUSION

Little data is available on this topic. Infused particles may induce organ failure, in particular pulmonary toxicity and SIRS. Further studies are needed to establish a link between the level of exposure to drug incompatibilities and clinical implication.

An Energy-Efficient Algorithm for Wearable Electrocardiogram Signal Processing in Ubiquitous Healthcare Applications

Rapid progress and emerging trends in miniaturized medical devices have enabled the un-obtrusive monitoring of physiological signals and daily activities of everyone’s life in a prominent and pervasive manner. Due to the power-constrained nature of conventional wearable sensor devices during ubiquitous sensing (US), energy-efficiency has become one of the highly demanding and debatable issues in healthcare. This paper develops a single chip-based wearable wireless electrocardiogram (ECG) monitoring system by adopting analog front end (AFE) chip model ADS1292R from Texas Instruments. The developed chip collects real-time ECG data with two adopted channels for continuous monitoring of human heart activity. Then, these two channels and the AFE are built into a right leg drive right leg drive (RLD) driver circuit with lead-off detection and medical graded test signal. Human ECG data was collected at 60 beats per minute (BPM) to 120 BPM with 60 Hz noise and considered throughout the experimental set-up. Moreover, notch filter (cutoff frequency 60 Hz), high-pass filter (cutoff frequency 0.67 Hz), and low-pass filter (cutoff frequency 100 Hz) with cut-off frequencies of 60 Hz, 0.67 Hz, and 100 Hz, respectively, were designed with bilinear transformation for rectifying the power-line noise and artifacts while extracting real-time ECG signals. Finally, a transmission power control-based energy-efficient (ETPC) algorithm is proposed, implemented on the hardware and then compared with the several conventional TPC methods. Experimental results reveal that our developed chip collects real-time ECG data efficiently, and the proposed ETPC algorithm achieves higher energy savings of 35.5% with a slightly larger packet loss ratio (PLR) as compared to conventional TPC (e.g., constant TPC, Gao’s, and Xiao’s methods).

Microbiological Quality of the Water used in Agriculture in Sardinia

BACKGROUND

The microbiological quality of the water used in irrigation is crucial for the safety of products, such as fruit and vegetables, especially when destined to be consumed raw. However, the microbiological quality of this water is not defined at a community regulatory level or at a national level.

METHODS

With our present work, we wanted to investigate the microbiological quality of the water used for crop irrigation in various Sardinian provinces. Since in most fields the irrigation water is filtered to remove any impurities, the sample was processed twice - both before and after the filtering process. Furthermore, with the purpose of hypothesising the potential health risks attributable to the consumption of crops from the tested fields, samples of horticultural product were collect. Any eventual seasonal differences in the values of microbial concentration were assessed. Microorganism faecal contamination indicators (Escherichia coli, total coliform and faecal streptococci), but even the presence of the opportunistic pathogen such as Pseudomonas aeruginosa were researched in irrigation water. Total mesophilic counts (TMC) were assessed at 36°C and 22°C. On horticultural products we researched both the indicators of process parameters, such as Escherichia coli, Total mesophilic counts at 30°C, Enterobacteriaceae, Total Psychrophilic counts and Pseudomonas aeruginosa, and pathogens, such as Salmonella spp, Listeria monocytogenes and Yersinia enterocolitica.

RESULTS

The number of target microorganisms, when present in irrigation water, was very limited: Escherichia coli, total coliform and faecal streptococci, were detected respectively in 48% and 67% of the water samples tested with average concentration values of 0.9, 1.2 and 1.4 log respectively. In fresh vegetable products, the total mesophilic counts (TMC) were found to have average values of 6.6x107 CFU/g. The average values of Enterobacteriaceae totalled 6.1x105 CFU/g; Escherichia coli was detected in only one sample (curly endive) with a value of 180 CFU/g.

CONCLUSION

The data highlights the high quality of the water and how this contributed to achieving satisfactory quality on prime material. However the use of filters, to eliminate impurities, and reservoirs, may represent a crucial issue, if not managed correctly.

Transcervical access, reversal of flow and mesh-covered stents: New options in the armamentarium of carotid artery stenting

In the last 25 years, the very existence of carotid artery stenting (CAS) has been threatened on a number of occasions. The initial disappointing results that even lead to the discontinuation of an early randomized controlled trial have improved considerably with time. Novel devices, advanced stent and equipment technology, alternative types of access and several types of filters/emboli protecting devices have been reported to reduce stroke/death rates during/after CAS and improve CAS outcomes. The present review will provide a description of the various technology advances in the field that aim to reduce stroke and death rates associated with CAS. Transcervical access, reversal of flow and mesh-covered stents are currently the most promising tools in the armamentarium of CAS.

Inverse design of high-Q wave filters in two-dimensional phononic crystals by topology optimization

Topology optimization of a waveguide-cavity structure in phononic crystals for designing narrow band filters under the given operating frequencies is presented in this paper. We show that it is possible to obtain an ultra-high-Q filter by only optimizing the cavity topology without introducing any other coupling medium. The optimized cavity with highly symmetric resonance can be utilized as the multi-channel filter, raising filter and T-splitter. In addition, most optimized high-Q filters have the Fano resonances near the resonant frequencies. Furthermore, our filter optimization based on the waveguide and cavity, and our simple illustration of a computational approach to wave control in phononic crystals can be extended and applied to design other acoustic devices or even opto-mechanical devices.

Simplified greywater treatment systems: Slow filters of sand and slate waste followed by granular activated carbon

One of the main actions of sustainability that is applicable to residential, commercial, and public buildings is the rational use of water that contemplates the reuse of greywater as one of the main options for reducing the consumption of drinking water. Therefore, this research aimed to study the efficiencies of simplified treatments for greywater reuse using slow sand and slow slate waste filtration, both followed by granular activated carbon filters. The system monitoring was conducted over 28 weeks, using analyses of the following parameters: pH, turbidity, apparent color, biochemical oxygen demand (BOD), chemical oxygen demand (COD), surfactants, total coliforms, and thermotolerant coliforms. The system was run at two different filtration rates: 6 and 2 m(3)/m(2)/day. Statistical analyses showed no significant differences in the majority of the results when filtration rate changed from 6 to 2 m(3)/m(2)/day. The average removal efficiencies with regard to the turbidity, apparent color, COD and BOD were 61, 54, 56, and 56%, respectively, for the sand filter, and 66, 61, 60, and 51%, respectively, for the slate waste filter. Both systems showed good efficiencies in removing surfactants, around 70%, while the pH reached values of around 7.80. The average removal efficiencies of the total and thermotolerant coliforms were of 61 and 90%, respectively, for the sand filter, and 67 and 80%, respectively, for the slate waste filter. The statistical analysis found no significant differences between the responses of the two systems, which attest to the fact that the slate waste can be a substitute for sand. The maximum levels of efficiency were high, indicating the potential of the systems, and suggesting their optimization in order to achieve much higher average efficiencies.

Superconducting Coplanar Waveguide Filters for Submillimeter Wave On-Chip Filterbank Spectrometers

We show the first experimental results which prove that superconducting NbTiN coplanar-waveguide resonators can achieve a loaded Q factor in excess of 800 in the 350 GHz band. These resonators can be used as narrow band pass filters for on-chip filter bank spectrometers for astronomy. Moreover, the low-loss coplanar waveguide technology provides an interesting alternative to microstrip lines for constructing large scale submillimeter wave electronics in general.

Dual functional nisin-multi-walled carbon nanotubes coated filters for bacterial capture and inactivation

BACKGROUND

Removal of pathogens from water is one way to prevent waterborne illness. In this paper, we developed dual functional carbon nanotube (CNT) modified filters for bacterial capture and inactivation, utilizing multi-walled CNTs (MWCNTs) to coat on commercially available filters and making use of the exceptional adsorption property of CNTs to adsorb a natural antimicrobial peptide-nisin on it. Two types of MWCNTs with different outer layer diameters were used (MWCNTs1: <8 nm in diameter; MWCNTs2: 10-20 nm in diameter).

RESULTS

The thickness of MWCNT layers, surface morphology, and surface hydrophobicity of both types of MWCNT coated filters were characterized. The MWCNT coating on filters significantly increased the surface hydrophobicity. The absorption of nisin and the capture of bacterial pathogens were correlated with increased surface hydrophobicity. The MWCNTs1 and MWCNTs2 filters with 1.5 mg MWCNTs loading captured 2.44 and 3.88 log of cells, respectively, from aqueous solutions containing a total of ~10(6) CFU/mL cells. Nisin deposit at the amount of 0.5 mg on the surfaces of MWCNT filters significantly reduced the viability of captured B. anthracis cells by 95.71-97.19 %, and inhibited the metabolic activities of the captured cells by approximately 98.3 %.

CONCLUSIONS

The results demonstrated that the MWCNT-nisin filters achieved dual functions in bacterial pathogen capture and inhibition in one single filtration step, which is potentially applicable in removing undesired microorganisms from water sources and inhibiting captured Gram positive bacteria activities.

Plasmonic circular resonators for refractive index sensors and filters

A plasmonic refractive index sensor based on a circular resonator is proposed. With all three dimensions below 1 μm, the sensor has a compact and simple structure granting it ease-of-fabrication and ease-of-use. It is capable of sensing trace amounts of liquid or gas samples. The sensing properties are investigated using finite elements method. The results demonstrate that the plasmonic sensor has a relatively high sensitivity of 1,010 nm/RIU, and the corresponding sensing resolution is 9.9 × 10(-5) RIU. The sensor has a relatively high quality factor of 35, which is beneficial for identifying each transmission spectrum. More importantly, the sensitivity is not sensitive to changes of structure parameters, which means that the sensitivity of the sensor is immune to the fabrication deviation. In addition, with a transmittance of 5% at the resonant wavelength, this plasmonic structure can also be employed as a filter. In addition, by filling material like LiNbO3 or liquid crystal in the circular resonator, this filter can realize an adjustable wavelength-selective characteristic in a wide band.

The influence of protozoa with a filtered and non-filtered seawater culture of Tetraselmis sp., and effects to the bacterial and algal communities over 10 days

In this study a filter was used to remove protozoa and its effects on a Tetraselmis sp. culture were evaluated in terms of final total lipid, final total dry weight, cell counts, and both the bacterial and algal communities. The protozoa species observed within this study was identified as Cohnilembus reniformis. It was observed that on the final day no C. reniformis were present in filtered cultures compared to the non-filtered culture which contained 40±3 C. reniformis/mL. The presence of C. reniformis within the culture did not affect the total lipid or the total dry weight recovered, suggesting that Tetraselmis sp. was capable of surviving and growing in the presence of C. reniformis. Overall it is suggested that an 11 μm filter was effective at removing protozoa, though growing a microalgae culture without filtration did not show any significant effect.

Oxidative photodegradation of ocular tissues: beneficial effects of filtering and exogenous antioxidants

The fact that light is necessary for life is generally accepted as an axiom. The extent to which light interacts and influences human biology, however, is often not fully appreciated. Exposure to sunlight, for instance, can both promote and degrade human health. There is now general scientific consensus that, although the eye evolved to respond to light, it is also damaged by excessive exposure. Light-mediated ocular damage is involved in the pathophysiology of many common forms of blindness. The type of ocular tissue damage induced by light exposure depends on the extent of exposure and wavelength. The tissues of the lens, cornea, and retina contain specific chemical moieties that have been proven to exhibit light-mediated oxidative degradation. Proteins and lipids present in the cornea, lens, and retina, meet all of the physical requirements known to initiate the process of oxidative photodegradation upon exposure to solar radiation. As such, different mechanisms have evolved in the lens, cornea, and retina to ameliorate such light-mediated oxidative damage. It appears, however, that such mechanisms are ill-matched to handle modern conditions: namely, poor diet and longer life-spans (and the degenerative diseases that accompany them). Hence, steps must be taken to protect the eye from the damaging effects of light. Preventative measures include minimizing actinic light exposure, providing exogenous filtering (e.g., through the use of protective lenses), and enhancing antioxidant defenses (e.g., through increased dietary intake of antioxidants). These strategies may yield long-term benefits in terms of reducing oxidative photodegradation of the ocular tissues.

Refining rare weed trait syndromes along arable intensification gradients

QUESTION

How does the conservation (rarity) value of arable weed communities differ along intensification gradients? Which functional traits best distinguish the weed communities of more and less extensively managed fields? Can the same traits predict the rarity of individual weed species?

LOCATION

Hungary.

METHODS

Using relevé data from 60 cereal and 70 stubble fields, together with weed trait data, we characterized community responses to arable intensification using functional trait analyses based on trait-convergence and trait-divergence assembly patterns. We also examined how well the broad-scale rarity status of species predicts their occurrence along intensification gradients, and how it maps onto our functional classifications describing intensification responses.

RESULTS

The response of weeds to intensification in cereal fields was best described by a functional classification based on species' flowering duration, maximum height and seed weight: weeds of extensively managed fields have short flowering seasons (2-5 mo) and particularly large or small seeds. The highest proportions of rare species also happen to be found in these groups. The rarest weeds among these species tend to be late-winter and early-summer annuals, while the rare species of stubble fields tend to be broad-leaved with low nitrogen requirements, small seeds and short height. Stubble fields showed a decline in weed cover with increasing application of fertilizer and distance from the field edge, but we could detect no strong associations of management factors with trait composition, perhaps because the intensification gradient across these fields was shorter.

CONCLUSIONS

Many rare Hungarian weeds are associated with traditional extensive farming practices. They are particularly characterized by short, midsummer flowering periods and by preference for low nitrogen levels, but a range of trait syndromes must be considered to understand their ecology and conservation. Analyses based on trait-divergence patterns, rather than trait-convergence patterns, provide better insights into the functional composition of weed communities, emphasizing the importance of disruptive filters in weed community assembly and the need for improved methods to detect such effects.

UK approach to assessing assays and filters designed to reduce the risk of transfusion-transmitted vCJD

Three cases of vCJD transmission by blood transfusion have been reported in the UK, and a fourth case discovered at post-mortem. Modelling has been conducted to predict the number of cases that may occur in the future through transfusion, based on estimates of prevalence, infectivity and susceptibility, and a number of steps have been taken to reduce the risk of transmission. These include deferral of previously transfused donors, leucocyte depletion of all components, importation of plasma for certain patient groups and for fractionation, and the collection of the majority of platelets from single donors (by apheresis). However, even with these interventions, some future cases are still predicted. The UK-wide Advisory Committee on the Safety of Blood, Tissues and Organs (SaBTO) considers the evidence for clinical and cost-effectiveness of any proposed intervention, such as prion assays and filters, and makes recommendations to the governments of the UK. The development of prion assays is challenging as prions do not generate an immune response, do not have nucleic acid and are present in blood in very low concentrations against a high background of normal prion protein. It is critically important that prion assays show high levels of sensitivity and - especially -specificity for a healthy blood donor population. Assessment is impacted by the very short supply of positive human samples, necessitating the use of animal models. Filters that are capable of removing prions from blood components have been developed and CE marked, but it is again necessary to use animal models to study their efficacy. Guidelines have been produced for the assessment of the quality of red cells filtered through these devices, and a clinical safety study has recently been completed. In conclusion, the evaluation of screening assays and prion filters is challenging, time-consuming and costly, but these evaluations are critical to policy making.

Effect of Filtration Conditions On Removal of Emerging waterborne pathogens

This study evaluated removal of live emerging waterborne pathogens by pilot‐scale conventional treatment with alum coagulation, flocculation, sedimentation, and filtration. The microbes tested were Cryptosporidium parvum oocysts, Encephalitozoon intestinalis spores, enteropathogenic Escherichia coli O157:H7, Aeromonas hydrophila, and bacteriophage MS2. The study showed the effects of filter run time, alternative loading rates, alternative filter media, and pH on pathogen removal. Results indicated that turbidity breakthrough was accompanied by breakthrough of all pathogens tested in this study. Results also suggest that the breakthrough of A. hydrophila and E. coli O157:H7 occurred more rapidly than that of turbidity. In general, filtration rate or alternative filter media configurations had no apparent effect on pathogen removal.