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This work describes a novel technique for the measurement of inorganic arsenic in water by generating arsine gas and detecting the conductivity of moving protons, H+ (aqueous or aq), produced by the reaction: Ag+ (aq) + AsH3 (gas, g) → AgAsH2 (solid, s) + H+ (aq). The detection is based on an electrochemical gradient of protons in a confined porous substrate (filter paper) and measures the change in the conductance due to the higher mobility of H+ compared to other ions. The conductance was measured with a pair of silver electrodes attached to opposite sides of the substrate with a bipolar pulse conductance technique. The method is established in theory and in practice. The theoretical equation for conductance change shows that a constant increase in conductance is directly proportional to the As(total) concentration. The method is validated with a standard reference material and applied to the measurement of the groundwater sample. [ABSTRACT FROM AUTHOR]

Actinomycetes are a suitable microbial group for the synthesis of lignocellulose-degrading enzymes. Enzymes that may degrade organic material, including cellulose, hemicellulose, and lignin, are released by actinomycetes. The aim of this research was to isolate actinomycetes from Rajkot, Gujarat, India’s soil and evaluate the activity of their cellulase and Xylanase enzymes. Starch Casein Agar (SCA) was used to identify a total of 30 isolates of actinomycetes. A qualitative plate assay (CMC-Na, Congo red) revealed that the highest zone of catalysis for MMD1 was 36 mm. Five strains were discovered to be effective for quantitative quantification of endoglucanase utilising filter paper and CMC as substrates: MMD1, MMD2, MMD3, MMD4, and MMD8. Following MMD 1 (endoglucanase 5.4 IU; FPase 4.4 IU), MMD 2 (endoglucanase 4.5 IU; FPase 3.4 IU) has demonstrated considerable endoglucanase and FPase activity. Beechwood xylan was used to treat sugarcane bagasse in order to test Xylanase, and 45% of the xylan (hemicellulose) fraction was obtained. MMD1 and MMD2 measured the xylanase enzyme activity (4.8IU and 4.2IU) in quantitative and qualitative assays (34 mm and 22 mm for BWX and 32 mm and 14 mm for agro-waste xylan). The strain MMD1 was identified as Streptomyces chartreusis through morphological, biochemical, and finally molecular characterization by 16S rRNA sequencing. It was then submitted to NCBI GenBank with the accession number MT254830. [ABSTRACT FROM AUTHOR]

Cellulose filter paper (CFP) was modified with poly(acrylic acid) (PAA) and/or poly(ethylene glycol)methacrylate (PEGMA), followed by Cu immobilization for 4-nitrophenol (4NP) reduction. Among these samples, Cu-immobilized CFP modified with PEGMA polymer (CFP@PEGMA-Cu) exhibited the highest Cu incorporation of 2.21%. Those having the copolymer (CFP@PAA-co-PEGMA-Cu) demonstrated the highest efficiency, completing 4NP reduction in 3 min with an impressive 99.45% conversion, a high-rate constant (k) of 27.5 × 10−3 s−1, and turnover frequency (TOF) of 18.36 h−1. Notably, the catalysts containing PAA maintained good reusability, preserving 97% conversion upon 9 cycles. These results suggest their promising applications in sustainable catalysis, offering the catalytic potential with simple preparation and low cost required. [ABSTRACT FROM AUTHOR]

The water-soluble bromophenoxy-substituted naphthalimide derivative 1 and its copolymer P1 with acrylamide were synthesized and the photophysical properties of their host–guest complexes with cucurbit[8]uril (CB[8]) were studied. Notably, the host–guest complex CB[8]·1 showed long-lived RTP on filter paper and demonstrated a humidity response, making it suitable for use as an encryption ink. Furthermore, the solid powder of the host–guest complex between P1 and CB[8] exhibited a 4 s afterglow emission. [ABSTRACT FROM AUTHOR]

Serum contains rich elemental information, and the elemental analysis of the serum using laser-induced breakdown spectroscopy (LIBS) can help with the diagnosis and treatment of cancer. In this work, serum specimens from breast cancer patients were used as samples, and the elements Mg, Ca, and K were analyzed using LIBS. Silver nanoparticles (Ag NPs) were introduced to enhance spectral emission intensities, and this technique is known as nanoparticle-enhanced LIBS (NELIBS). An Ag NP-coated filter paper (Ag NP paper) substrate was prepared and was compared with silicon and aluminum substrates for NELIBS analysis. The Ag NP paper substrate showed lower spectral intensity variances and better elemental distribution uniformity due to the reduced coffee-ring effect compared with silicon and aluminum substrates. The enhanced effect of the Ag NP paper was optimized by adjusting serum volume and Ag NPs concentration. It was found that Mg, Ca, and K required different optimal conditions for spectral enhancement. The highest enhancement factors (EF) for Mg, Ca, and K were 1.85, 1.76, and 3.10, respectively. The electron temperature (Te) and electron number density (Ne) of NELIBS plasmas were measured using the Boltzmann plot and Stark broadening methods and compared with those of the normal LIBS plasmas. The Te and Ne of the NELIBS and normal LIBS samples were generally comparable with each other. Higher Ag NP concentrations led to lower Te values for NELIBS plasmas. [ABSTRACT FROM AUTHOR]

As air pollution escalates, the need for air filters increases. It is better that the filters used be based on natural fibers, such as non-wood fibers, which cause low damage to the environment. However, the short fiber lengths, low apparent densities, and high volumes of non-wood materials can make it challenging to prepare filter paper with the required mechanical and physical properties. In that context, this study focused on utilizing bamboo fibers to fabricate filter paper by employing the anthraquinone soda pulping method. The pulp underwent bleaching and oxidation processes, with the incorporation of cationic starch (CS) and polyvinyl alcohol (PVA) to enhance resistance properties, resulting in the creation of handmade filter papers. The findings revealed that the tear, burst, and tensile strength of filter paper increased with the oxidation and addition of CS and PVA. Air permeability increased with addition of PVA and combination of CS and PVA. FTIR demonstrated the conversion of hydroxyl groups in cellulose chains to carboxyl groups due to oxidation. SEM images illustrated alterations in the fiber structure post-oxidation treatment, with CS reducing pores while PVA and the CS-PVA combination enlarged pore size and enhanced porosity. The BET surface area surface area expanded with oxidation and the addition of the CS-PVA blend, indicating heightened filter paper porosity. Notably, the combined inclusion of CS and PVA not only augmented mechanical strength but also increased porosity while maintaining pore size. [ABSTRACT FROM AUTHOR]

Objectives: Endoscopic ultrasound‐guided tissue acquisition (EUS‐TA) is used for pathological diagnosis and obtaining samples for molecular testing, facilitating the initiation of targeted therapies in patients with pancreatic cancer. However, samples obtained via EUS‐TA are often insufficient, requiring more efforts to improve sampling adequacy for molecular testing. Therefore, this study investigated the use of oil blotting paper for formalin fixation of samples obtained via EUS‐TA. Methods: This prospective study enrolled 42 patients who underwent EUS‐TA for pancreatic cancer between September 2020 and February 2022 at the Osaka International Cancer Institute. After a portion of each sample obtained via EUS‐TA was separated for routine histological evaluation, the residual samples were divided into filter paper and oil blotting paper groups for analysis. Accordingly, filter paper and oil blotting paper were used for the formalin fixation process. The total tissue, nuclear, and cytoplasm areas of each sample were quantitatively evaluated using virtual slides, and the specimen volume and histological diagnosis of each sample were evaluated by an expert pathologist. Results: All cases were cytologically diagnosed as adenocarcinoma. The area ratios of the total tissue, nuclear, and cytoplasmic portions were significantly larger in the oil blotting paper group than in the filter paper group. The frequency of cases with large amount of tumor cells was significantly higher in the oil blotting paper group (33.3%) than in the filter paper group (11.9%) (p = 0.035). Conclusions: Oil blotting paper can increase the sample volume obtained via EUS‐TA on glass slides and improve sampling adequacy for molecular testing. [ABSTRACT FROM AUTHOR]

Background: Accuracy of molecular tools for the identification of parasites that cause human cutaneous leishmaniasis (CL) could largely depend on the sampling method. Non-invasive or less-invasive sampling methods such as filter paper imprints and cotton swabs are preferred over punch biopsies and lancet scrapings for detection methods of Leishmania based on polymerase chain reaction (PCR) because they are painless, simple, and inexpensive, and of benefit to military and civilian patients to ensure timely treatment. However, different types of samples can generate false negatives and there is a clear need to demonstrate which sample is more proper for molecular assays. Methodology: Here, we compared the sensitivity of molecular identification of different Leishmania (Viannia) species from Peru, using three types of sampling: punch biopsy, filter paper imprint and lancet scraping. Different composite reference standards and latent class models allowed to evaluate the accuracy of the molecular tools. Additionally, a quantitative PCR assessed variations in the results and parasite load in each type of sample. Principal findings: Different composite reference standards and latent class models determined higher sensitivity when lancet scrapings were used for sampling in the identification and determination of Leishmania (Viannia) species through PCR-based assays. This was consistent for genus identification through kinetoplastid DNA-PCR and for the determination of species using FRET probes-based Nested Real-Time PCR. Lack of species identification in some samples correlated with the low intensity of the PCR electrophoretic band, which reflects the low parasite load in samples. Conclusions: The type of clinical sample can directly influence the detection and identification of Leishmania (Viannia) species. Here, we demonstrated that lancet scraping samples consistently allowed the identification of more leishmaniasis cases compared to filter paper imprints or biopsies. This procedure is inexpensive, painless, and easy to implement at the point of care and avoids the need for anesthesia, surgery, and hospitalization and therefore could be used in resource limited settings for both military and civilian populations. Author summary: Human cutaneous leishmaniasis affects low-income populations living in places far from health services. The early sampling and detection of the parasite are necessary for timely treatment, however there are no uniform sampling criteria, thus the sensitivity of molecular tests may vary due to various factors such as the type of sample, the time of the disease and the parasite load in the lesion. In this study, we compared the performance of three sampling methods for molecular identification of the genus and Leishmania (Viannia) species in Peru. Several analytical methods, including composite reference standards and latent class models, suggested that lancet scraping might be the best approach for parasite genus detection by kDNA-PCR and for parasite species determination by FRET probes-based Nested Real-Time PCR. [ABSTRACT FROM AUTHOR]

There is an increasing need for accessible methods to monitor soil health. Our primary objective was to evaluate an accessible, do-it-yourself method for measuring the maximum water holding capacity – we call this the funnel, filter paper, and drainage (MWHCFFPD) method. First, we compared MWHCFFPD to the water desorption method via pressure cells (WHCPC), routinely used for generating soil water retention curves, using 10 soils from a wide range of textures (4–55% clay). Second, we tested the sensitivity of the MWHCFFPD to methodological variations likely encountered by citizen scientists. The two methods were quite comparable in precision, with mean coefficient of variances of 3.5% and 4.4% for the FFPD and water desorption method, respectively. The MWHCFFPD and WHCPC methods were comparable, with MWHCFFPD best correlating to WHCPC at −2.45 kPa (R2 = 0.98). The MWHCFFPD method is somewhat sensitive to some methodological modifications, most notably variation in water source, but with standardized protocols could be scientifically robust. Overall, MWHCFFPD can be used as a simple and affordable test of sieved soil structure and organic matter, and thus has potential to expand soil health monitoring. [ABSTRACT FROM AUTHOR]

BACKGROUND: Due to the unstable drug release rate of uniaxial bone scaffolds, multi-structure composite printing methods have been sought in and outside China in recent years. Currently, coaxial drug-loaded bone scaffolds, which combine drug-loaded sustained release system with bone transplantation and repair technology, not only replace the defective bone after implantation, but also release drugs slowly, providing a microenvironment conducive to bone formation at the implant site. OBJECTIVE: To explore and assess the in vitro antibacterial properties of uniaxial and coaxial minocycline hydrochloride bone scaffolds. METHODS: Rapid prototyping technology was used to prepare uniaxial hydroxyapatite/silk fibroin-polyvinyl alcohol scaffold, uniaxial hydroxyapatite/silk fibroin-polyvinyl alcohol scaffold, coaxial hydroxyapatite/silk fibroin-polyvinyl alcohol scaffold, and coaxial hydroxyapatite/silk fibroin-polyvinyl alcohol scaffold, respectively, which were named S1, S2, T1 and T2. The morphology, porosity, degradation performance, in vitro sustained-release performance and cytotoxicity of scaffolds were characterized. Four kinds of bone scaffolds were immersed in PBS to prepare the extracts at different time points (1, 3, 5, 7, 14, 21, and 28 days). The qualitative filter paper was placed into the extract for 24 hours. The filter paper was co-cultured with Porphyromonas gingivalis and Fusobacterium nucleatum for 72 hours. The bacteriostatic effect of four groups of scaffolds was detected by the agar diffusion method. RESULTS AND CONCLUSION: (1) Scaffold characterization: Four groups of scaffolds were well formed. The surface of micro-wires in the S1 and S2 groups was dense and smooth, and the surface of micro-wires in the T1 and T2 groups was rough. Porosity was between 40%-47% and met the requirements of bone scaffolds. Compared with the S2 group, sustained release time was longer in the T2 group. The sustained release concentration of the drug was between 1- 10 μg/mL for a long time, which was more conducive to bacteriostasis and osteogenesis. After 10 weeks of immersion in PBS in vitro, the degradation rate of the coaxial printed bone scaffold was faster than that of the corresponding uniaxial printed bone scaffold, and the degradation rate of the coaxial loaded bone scaffold was lower than that of the coaxial non-loaded bone scaffold. The four groups of scaffold extracts were co-cultured with osteoblasts respectively. CCK-8 assay displayed that the cell proliferation rate was greater than 75%, which met the requirements of biocompatibility. (2) In vitro antibacterial effect: S1 and T1 did not have antibacterial activity. S2 and T2 had an obvious antibacterial effect. Under the extraction solution on day 28, the diameter of Porphyromonas gingivalis and Fusobacterium nucleatum inhibition zone in the S2 group was smaller than that in the T2 group (P < 0.05). (3) These findings exhibit that hydroxyapatite/silk fibroin-polyvinyl alcohol scaffolds with coaxial minocycline have good physical properties and bacteriostatic properties. [ABSTRACT FROM AUTHOR]

In this study, the photothermal performance of lignin-based nanospheres was investigated. Subsequently, a photothermal actuator was prepared using lignin-based carbon nanospheres (LCNSs). The results demonstrated that LCNSs exhibited an impressive photothermal conversion efficiency of up to 83.8%. This extreme efficiency significantly surpasses that of lignin nanospheres (LNSs) and covalently stabilized LNSs (HT-LNSs). As a structural material, a hydrophobic coating was effectively engineered by LCNSs on the filter paper, achieving a water contact angle of 151.9° ± 4.6°, while maintaining excellent photothermal effects (with a temperature increment from room temperature to 138 °C in 2 s). When employing hydrophobic filter paper as the substrate for the photothermaldriven actuator, under the influence of a 1.0 W/cm2 power–density NIR laser, the material exhibited outstanding photothermal actuation, achieving speeds up to 16.4 mm/s. In addition, the direction of motion of the actuator can be adjusted in accordance with the location of the NIR light irradiation. This study offers valuable perspectives on the application of LNSs for highvalue applications and the development of innovative photothermal-driven actuators. [ABSTRACT FROM AUTHOR]

Treatment of cryptococcal meningitis relies primarily on flucytosine (5FC), which is also used to treat candidiasis and infections caused by Cryptococcus neoformans. High dosages of this drug, despite its therapeutic properties, may cause hazardous side effects such as bone marrow suppression, hepatotoxicity, and gastrointestinal toxicity. The detection of trace amounts of 5FC medication may aid in tracking the treatment's efficacy and mitigating unwanted effects. Surface-enhanced Raman spectroscopy (SERS) is a rapid, reliable, and precise approach for detecting extremely low amounts of biological and chemical compounds. A filter paper-based SERS biosensor coated with silver nanoparticles (AgNPs) were employed to detect the 5FC drug. The AgNPs fabricated via the chemical reduction method were characterized by FE-SEM, TEM, XRD, AFM, and UV-Vis spectroscopy. Plasmonic active sites were made by coating the filter paper substrate with AgNPs to detect the 5FC drug's molecular vibrations. As the 5FC drug was coated onto the filter paper substrate, the AgNPs interacted with it, allowing for the detection of very low concentrations of the drug. The SERS filter paper substrate could detect concentrations of 5FC as low as 10−10 M. The Raman spectra and peak signals obtained experimentally were also simulated and validated using the density functional theory (DFT) approach. Six sets of measurements were taken, and the average RSD was obtained to be 4.62%. The experimentally measured enhancement factor for recognizing molecular vibrations of the 5FC was 9.065 × 107, and it was numerically estimated as 10.044 × 107. Therefore, the fabricated SERS-based filter paper substrate is useful for drug monitoring since they can detect even trace amounts of the targeted drug. [ABSTRACT FROM AUTHOR]

Biochar (BC) was used in Trichoderma sp. culture to produce high-activity cellulase on a laboratory scale. The biochar was added into the flask before being applied to the fermenter to identify the enhancement effect and to determine the best amount of addition and the most suitable incubation period. Cellulase production was performed with a working volume of 4 L, and enzymatic hydrolysis was conducted to evaluate the saccharification ability of the enzyme. During incubation, the activities of three enzymes (Endoglucanase (EG), β-glucosidase (BGL), and cellobiohydrolase (CBH)) were measured for three days, and the cellulase activity was determined using a filter paper unit (FPU). In flask scale, EG, BGL, and CBH activities were increased by 1.4, 2.1, and 1.8 folds, respectively, and the incubation period was shortened by adding BC. In the fermenter scale, EG, BGL, and CBH activities were noticeably enhanced by 12.1, 5.8, and 7.2 folds, respectively, and FPU was 42.1 (9.8 folds). Additionally, the conversion rates of cellulose and steam exploded softwood and hardwood were 109.4%, 75.4%, and 87.3%, which were similar to a commercial enzyme (Cellic CTec II). This study demonstrated that biochar could be used to produce high-activity cellulase in a shorter period and suggests a novel method for effective cellulase production. [ABSTRACT FROM AUTHOR]

The filter paper (FP) method, a cost-effective, versatile, and convenient approach, has found extensive application in analyzing fine-grained soils, enabling the successful measurement of a broad spectrum of total and matric suctions. However, using the FP method in sand with a limited range of suction profiles has been notably underrepresented in the existing literature. Therefore, this study investigated the applicability of the contact FP method in establishing soil water retention curves (SWRCs) using five distinct FP calibration curves for 10 poorly graded sands. Among these calibration curves, the one presented by Chandler yielded the highest suction values, which were followed by those of ASTM. Furthermore, the FP results were subjected to fitting with a mathmatical model, which led to the observation that the overall trends in the obtained SWRCs displayed smooth sigmoidal shapes, resulting in a complete and coherent SWRCs. The SWRC results of five sand samples were assessed through validation against the hanging column technique (HCT) results, indicating a high degree of concordance and affirming the suitability of the FP method for sands characterized by a limited suction profile. Notably, the entire range of suction values fell within the 0.01–20 kPa range based on the calibration curves presented by Chandler and ASTM for all the examined sand samples, except sands 9 and 10. Furthermore, the suction values were unobtainable using the two aforementioned calibration curves within the ranges of 0.01–1.47 kPa and 0.01–0.172 kPa. [ABSTRACT FROM AUTHOR]

A thin, lightweight and flexible electromagnetic interference (EMI) shielding paper composite is an urgent need for modern military confrontations. Herein, a sandwich-structured EMI shielding paper composite with an easy pavement consisting of a filter paper layer, middle AgNWs/MXene layer, and polyvinyl butyral (PVB) layer was constructed by vacuum-assisted filtration, spraying and air-drying. The middle AgNWs/MXene compound endowed the filter paper with excellent electrical conductivity (166 S cm−1) and the fabricated filter paper–AgNWs/MXene–PVB composite exhibits superior EMI shielding (30 dB) with a 141 μm thickness. Remarkably, the specific EMI shielding effectiveness (SSE/t) of the filter paper–AgNWs/MXene–PVB composite reached 13,000 dB cm2 g−1 within the X-band frequency range. This value represents one of the highest reported for cellulose-based EMI shielding materials. Therefore, our sandwich-structured filter paper composite with superior EMI shielding performance can be used in the medical and military fields. [ABSTRACT FROM AUTHOR]

The surface-enhanced Raman scattering (SERS) properties of low-dimensional semiconducting MXene nanoflakes have been investigated over the last decade. Despite this fact, the relationship between the surface characteristics and SERSing performance of a MXene layer has yet to be comprehensively investigated and elucidated. This work shows the importance of surface morphology on the overall SERS effect by studying few-layer Ti3C2Tx MXene-based SERS substrates fabricated by vacuum-assisted filtration (VAF) and spray coating on filter paper. The VAF deposition results in a dense MXene layer suitable for SERS with high spot-to-spot and substrate-to-substrate reproducibility, with a significant limit of detection (LoD) of 20 nM for Rhodamine B analyte. The spray-coated MXenes film revealed lower uniformity, with a LoD of 50 nM for drop-casted analytes. Moreover, we concluded that the distribution of the analyte deposited onto the MXene layer is affected by the presence of MXene aggregates created during the deposition of the MXene layer. Accumulation of the analyte molecules in the vicinity of MXene aggregates was observed for drop-casted deposition of the analyte, which affects the resulting SERS enhancement. Ti3C2Tx MXene layers deposited on filter paper by VAF offer great potential as a cost-effective, easy-to-manufacture, yet robust, platform for sensing applications. [ABSTRACT FROM AUTHOR]

The potential of native as well as acid/alkali pre-treated paddy straw was investigated as inducer substrate for Aspergillus terreus mediated cellulase and xylanase production. The cellulose, hemicellulose and lignin contents of native straw were found to be 25.94%, 17.64% and 15.82%, respectively. However, in the acid/alkali treated straw, cellulose content substantially increased to 48.09%, whereas hemicellulose and lignin contents were reported to be particularly low (11.72%, 5.08%, respectively). The FTIR spectra of native and pre-treated paddy straw further supported the variation in their chemical constituents. A. terreus repertoires were cultivated on native and treated paddy straw under solid state fermentation (SSF) and liquid fermentation (LF) conditions. The LF cultures showed higher cellulase and xylanase activities (Filter Paper cellulase: 45.33 U/L, Carboxymethyl cellulase: 104.75 U/L, β-glucosidase 80.44 U/L, Avicelase: 22.72 U/L and Xylanase: 623.69 U/L) than the respective SSF cultures. Significantly high activities of exoglucanases and endoglucanases were obtained when native straw was used as the growth substrate. The scanning electron micrographs of native and treated straw exhibited disintegration after being subjected to biological treatments, confirming the hyphal adhered growth and production of hydrolysing secretomes by the fungus. Cultivation of A. terreus on native paddy straw in LF culture system resulted in better enzyme production, and holds promise for further optimization. [ABSTRACT FROM AUTHOR]

In this work, solid-surface fluorescence spectra of Rhodamine B (RhB) and fluorescein (FLU), two extensively used fluorophores, were studied and their concentrations were semi-quantitatively determined using the three-dimensional excitation–emission matrix (3D-EEM) data. In order to measure the solid fluorescence spectra, a trace amount of fluorophores was physically adsorbed on a piece of filter paper as a fluorescent paper, and the fluorescence spectra were recorded from the surface of the fluorescent paper instead of the inner parts of the solution. The spectral measurement was performed utilizing a routine spectrofluorimeter designed to measure the fluorescence of solution only by placing the fluorescent paper in a simple handmade holder at an adjusted incident angle of radiation. The results revealed a significant increase in the fluorescence intensity of the fluorescent paper strip compared to the solution phase. Moreover, in the RhB–FLU paper strip the forster resonance energy transfer was observed between FLU and RhB, similar to the observed phenomenon in the solution phase. For quantifying fluorophores, the EEM data were successfully resolved by applying multivariate partial least squares and parallel factor analysis (PARAFAC) modeling, and the results were compared with the univariate method. This study may provide a general guideline in further developing the solid fluorescence measurement of concentrated solutions or solid samples that have fluorescence measurement limitations such as high self-absorption and highly scattered spectra by using a conventional spectrofluorimeter, and also of biological samples where a trace amount of the analyte is available and high sensitivity is required. [ABSTRACT FROM AUTHOR]

To achieve integrated resource utilization of graphite tailings to improve their water-holding capacity, river silt and cow dung powder were added to graphite tailings as organic matter improvers. Improver ratios were designed using 4 g cow dung powder and 20, 30, and 50 g river silt. Soil–water characterization tests were performed using a combined tensiometer and filter paper method based on optimum density measurements. Analysis of the influence of river silt dosing on the soil–water characteristic curves of improved graphite tailing specimens was performed with data fitting using the Van Genuchten model. Here, we investigated the effect of river silt dosing on the internal pore structure and water-holding capacity of modified graphite tailing samples and verified the applicability of the model to graphite tailings. Our results demonstrate that the organic matter improver incorporated into graphite tailings can improve the internal structural compactness of graphite tailings, improving the water holding capacity. With an increase in river silt dosage, the saturated water content is larger, and the residual water content increases and then decreases. When river silt dosage is 30 g, the residual water content is the highest at a value of 3.32%. The van Genuchten model was highly accurate for assessing the graphite tailings. With an increase in river silt doping, the internal pore space first decreased and then increased, and the internal structure gradually became compact and loosened. The internal structure was in the optimal state in the experimental study when the dosage of cow dung powder was 4 g and the dosage of river silt was 30 g. The water holding capacity was optimal at this time. The results of this study provide a theoretical foundation for graphite-tailing-based mine reclamation and play a guiding role in exploring the value of the hydraulic characteristic index parameters when applying graphite tailings engineering. [ABSTRACT FROM AUTHOR]

Exploring an appropriate immobilization approach to enhance catalytic activity and reusability of cellulase is of great importance to reduce the price of enzymes and promote the industrialization of cellulose-derived biochemicals. In this study, Fe3O4 magnetic nanoparticles (MNPs) were functionalized with meso-2,3-dimercaptosuccinic acid to introduce carboxyl groups on the surface (DMNPs). Then, melamine–glutaraldehyde dendrimer-like polymers were grafted on DMNPs to increase protein binding sites for the immobilization of processive endoglucanase EG5C-1. Moreover, this dendrimer-like structure was beneficial to protect the conformation of EG5C-1 and facilitate the interaction between substrate and active center. The loading capacity of the functionalized copolymers (MG-DMNPs) for EG5C-1 was about 195 mg/g, where more than 90% of the activity was recovered. Immobilized EG5C-1 exhibited improved thermal stability and increased tolerability over a broad pH range compared with the free one. Additionally, MG-DMNP/EG5C-1 biocomposite maintained approximately 80% of its initial hydrolysis productivity after five cycles of usage using filter paper as the substrate. Our results provided a promising approach for the functionalization of MNPs, enabling the immobilization of cellulases with a high loading capacity and excellent activity recovery. [ABSTRACT FROM AUTHOR]

By focusing our attention on nitrogen components in plants, which are important for cultivation management in data-driven agriculture, we developed a simple, rapid, non-chemical and simultaneous quantification method for proteinic and nitrate nitrogen in a leaf model based on near-infrared (NIR) spectroscopic information obtained using a compact Fourier Transform NIR (FT-NIR) spectrometer. The NIR spectra of wet leaf models impregnated with a protein–nitric acid mixed solution and a dry leaf model obtained by drying filter paper were acquired. For spectral acquisition, a compact MEMS (Micro Electro Mechanical Systems) FT-NIR spectrometer equipped with a diffuse reflectance probe accessory was used. Partial least square regression analysis was performed using the spectral information of the extracted absorption bands based on the determination coefficients between the spectral absorption intensities and the contents of the two-dimensional spectral analysis between NIR and mid-infrared spectral information. Proteinic nitrogen content in the dry leaf model was well predicted using the MEMS FT-NIR spectroscopic method. Additionally, nitrate nitrogen in the dry leaf model was also determined by the provided method, but the necessity of adding the data for a wider range of nitric acid concentrations was experimentally indicated for the prediction of nitrate nitrogen content in the wet leaf model. Consequently, these results experimentally suggest the possibility of the application of the compact MEMS FT-NIR for obtaining the bioinformation of crops at agricultural on-sites. [ABSTRACT FROM AUTHOR]

The study aimed to explore the nutritional value of sea buckthorn by-products and the antibacterial effects of their extracts on Escherichia coli. The experiment employed the sodium nitrite-aluminum nitrate method to determine flavonoid content, while alcohol extraction and water extraction methods were used to extract active substances from sea buckthorn by-products. The antibacterial effects of sea buckthorn by-product extracts on Escherichia coli were investigated by the filter paper method, perforation method, and broth dilution method. The results showed that the dry matter (DM) content of sea buckthorn by-products was 97.98%, ash content was 3.41%, crude protein (CP) content was 12.87%, and crude fat (EE) content was 22.48%. With the increase of sea buckthorn by-product addition, gas production showed a decreasing trend. Among alcohol extraction and water extraction methods, the constant broth dilution method exhibited the best antibacterial effect. In the alcohol extraction method, the filter paper method showed good antibacterial effect with an inhibition zone of 14.6 mm. In the water extraction method, the filter paper method did not exhibit a significant inhibition zone, and the perforation method was not significant in both alcohol extraction and water extraction methods. The study suggests that sea buckthorn by-products have rich nutritional value, and alcohol extraction is more effective in inhibiting Escherichia coli compared to water extraction. [ABSTRACT FROM AUTHOR]

The article discusses the synthesis and catalytic properties of Donor-Acceptor Stenhouse Adducts (DASAs). DASAs are triene substances that can be prepared using specific reagents and conditions. The study explores the use of Lewis acids as catalysts for transforming DASAs into their ring isomers, and suggests potential applications as photosensors and Lewis acid sensors. The document provides detailed experimental procedures and results for the synthesis and characterization of various compounds, as well as a general procedure for the one-pot cyclization of DASAs. [Extracted from the article]

The large-scale development of flexible electrode is urgently needed for water electrosplitting. Herein, the common and low-cost filter paper (FP) is utilized as the substrate to adjust the flexible property of the catalytic electrode. Through an electroless plating method, the NiFeP alloys were deposited onto the filter paper, which acted as the flexible and self-supported electrode for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The resultant NiFeP@FPs require low overpotentials of 158 mV for HER and 282 mV for OER to deliver a current density of 10 mA cm−2, and exhibit a good stability of 30 h in 1 M KOH. The synergistic effect of Fe–Ni sites regulates electron structure and boosts the catalytic activity. Benefited from good hydrophilicity and interlaced fiber structure of filter paper, electrolyte penetration and electron transfer in the sample are promoted. The assembled two-electrode electrolyzer only requires 1.814 V to achieve 100 mA cm−2 for overall water splitting and shows excellent stability. This work provides a new strategy for the development of flexible and efficient electrodes for water splitting, which advances the development of wearable electronic devices. [Display omitted] • The flexible filter paper-based electrode was successfully synthesized. • The good hydrophilicity and porous structure facilitated electrolyte permeation. • The sample required low overpotentials of 158 mV for HER and 282 mV for OER. • The two-electrode electrolyzer provided 100 mA cm−2 at a low voltage of 1.814 V. [ABSTRACT FROM AUTHOR]

Aims: Information on breastfeeding and safety of biologics in infants is lacking due to difficulties in case collection. We evaluated methods for determining the concentration of biologics in breast milk using a dry filter method that can simplify the collection, storage and transport of breast milk. Methods: To generate dried filter paper (DFP) samples, approximately 30 μL of breast milk was placed onto a Whatman 903 card and punched out. After extraction, the supernatant was measured using an enzyme‐linked immunosorbent assay. Three concentrations of each drug were prepared in liquid breast milk (LBM) and DFP samples to determine their stability up to 28 days after storage at 2–8°C or −20°C for LBM and 25 ± 5°C for DFP. LBM and DFP samples were also provided by nursing mothers using biologics during lactation, and drug concentrations in both samples were compared. The agreement between the two measurement methods was confirmed by Bland–Altman analysis. Results: Breast milk was provided by 12 mothers who used biologics (tocilizumab, abatacept, etanercept, golimumab, sarilumab and belimumab). The coefficients of variation for within‐run and between‐run precision for the six drugs were within 15% for both LBM and DFP, and accuracy was within 90%–110% of the quality controls. After 28 days, concentrations remained at more than 90%. The difference between the values obtained by each method was within the acceptable range of error (−12.1 to +16.6 ng/mL). Conclusions: A method for determining the concentration of biologics using DFP is expected to help improve pharmacotherapy for lactating women. [ABSTRACT FROM AUTHOR]

The flame spread behavior over a filter paper in opposed flow was investigated on the ISS/Kibo, and the results were compared with the flammability map predicted in advance by scale analysis for a two-dimensional flame. The on-orbit experiments were conducted in the solid combustion experimental module (SCEM) as the first combustion test of the FLARE project by JAXA. A filter paper with a length of 130 mm, a width of 40 mm or 20 mm, and a thickness of 0.12 mm was used as the specimen. The opposed flow velocity and the oxygen concentration were varied from 0 cm/s to 25 cm/s, and from 13.5% to 34%, respectively. The ambient pressure is 101.3 kPa. The predicted limiting curve reasonably agreed with the minimum limiting oxygen concentration observed. On the other hand, in extremely slow flows, very robust flames were observed beyond the limiting curve. When the condition reached the limit of two-dimensional flame, the flame front changed from a linear shape to a spherical shape (flamelet) to shorten the preheat zone length, reducing the radiative heat loss to survive. In these cases, the flamelet was sustained for a long time (> 100 s), and a large amount of decomposed gas was released at the periphery of the pyrolysis zone generating a combustible vapor cloud around the spherical flame font. The presence of a long-life robust flamelet and the accumulation of such combustible mist can be fire hazards in microgravity. [ABSTRACT FROM AUTHOR]

A novel 1,8-naphthalimide fluorescent probe (BNAS) containing 2-thiopheneethylamine moiety was designed and synthesized for analyzing the composition of N,N-dimethylformamide (DMF)/deionized water (H2O) mixtures. With the increase of DMF content, the fluorescence of the system was enhanced from dark to bright yellow-green. Taking 15% (volume) DMF content as the dividing point, the fluorescence intensity of the system at 535 nm showed two good linear relationships with the DMF content 1–15% and 15–99%, based on which the composition of the DMF/H2O mixtures with a volume ratio of 1/99–99/1 could be quickly and efficiently analyzed with high selectivity and sensitivity. BNAS can be applied in real sample assay and further be loaded onto filter paper to make a portable sensor. The mechanism of BNAS response to DMF/H2O composition was also explored. [ABSTRACT FROM AUTHOR]

Long-term excessive uptake of fluoride through potable water will cause adverse effects on human health. Therefore, it is of great significance to detect and remove excessive fluoride in potable water. Here, we reported a multi-functional Zr-based coordination polymer namely CP-1, which could realize the visual detection and effectively selective adsorption of fluoride. The investigation of fluoride adsorption manifested that the maximum fluoride adsorption capacity of CP-1 could reach 48.78 mg g−1 and selective adsorption capacity kept stable in a wide range of pH. By fluorometric approaches, the detection of limit of F− could achieve 1.55 × 10–6 mol L−1 based on CP-1. Moreover, the fluorescence test paper fabricated by in situ growth of CP-1 onto the surface of filter paper was proved to realize the visual detection of fluoride. [ABSTRACT FROM AUTHOR]

The current study was conducted at the different villages of the Arajiline block of Varanasi district, Uttar Pradesh, India during November, 2022-June, 2023 to evaluate the variability of soil properties and nutrient indexof soils. The random sampling technique was used to collect 40 soil samples at different locations with the help of GPS at 0-15 cm depth. The collected soil samples were air-dried in shade at room temperature, passed through a 2 mm filter paper, and analyzed for different physico-chemical properties. The result revealed that the TS (range 8.2-81.3%), VFS (range 4.2-35.5%), Silt (range 10.1-54.2%), Clay (range 7.7-38.8%), BD (range 1.08-1.45 g cm-3), PD (range 2.04-2.33), Porosity (range 30.24-51.56%) pH (range 6.4-7.8), EC (range 0.1-0.3 dS m-1), OC (0.2-0.6%), and available N, P, K, S, Ca, and Mg varied from 130.12-260.30 kg ha-1, 14.2-23.2 kg ha-1, 145.0-240.0 kg ha-1, 7.5-17.6 kg ha-1, 3.8-8.2 cmol(P+)/kg, and 2.1-4.1 cmol(P+)/kg, respectively. The findings indicated that the studied soils were slightly acidic to moderately acidic and free from salinity hazards; 70% of the soil samples were low in organic carbon, 30% were medium in organic carbon, and 100% of the soil samples were low in available N and medium in available P, K, and S. 100% of soil samples were found to be sufficient in exchangeable Ca and Mg. The findings of this research could help in crop nutrient management, fertilizer recommendation, and decision-making for increasing agricultural production and farmer profitability. [ABSTRACT FROM AUTHOR]

In the current strategy, a highly sensitive and fast one-step colorimetric assay for trace determination of Cu2+ in water is presented. The planned assay was based upon the use of varnish polish-modified filter paper printed with 2-[5-(2-hydroxy-5-sulfophenyl)-3-phenyl-1-formazyl] benzoic acid monosodium salt, commercially named zincon. Under optimal conditions, the designed assay readily recognised the formation of blue–purple-coloured Cu–ZI chelate in less than 10 min. The proposed probe was able to detect Cu2+ in the concentration range from 0.04 to 10 μg/mL (6.34 × 10−1 to 1.59 × 103µM), with low limit of detection (LOD) of 0.01 μg/mL (1.59 × 10−1 µM). The LOD was 10-fold lower than the allowable level for Cu2+ in drinking water set by WHO legislation. The assay was applied for Cu2+determination in water with acceptable recoveries (89.6–102.1%) and precision (<3%). Therefore, the proposed sensing assay might be considered as a potential rapid and low-cost candidate for total determination and speciation of Cu2+in water samples. [ABSTRACT FROM AUTHOR]

The combination of electron-deficient viologen ligands with electron-rich POMs is a typical acceptor–donor system that has recently received much attention. Under solvothermal and hydrothermal conditions, by introducing three symmetric viologen ligands into POM-based hybrid materials, we successfully constructed four POMs–viologen inorganic–organic hybrid compounds, namely (1,3-bcbpy)2·(δ-Mo8O26) (1) (1,3-bcbpy·2Cl = 1,1′-bis(3-carboxybenzyl)-4,4′-bipyridine dichloride), {CoII(1,4-bcbpy)2(H2O)2[H2(β-Mo8O26)]}·2H2O·2CH2O (2), (1,4-bcbpy)2·(δ-Mo8O26)·2H2O (3) (1,4-bcbpy·2Cl = 1,1′-bis(4-carboxybenzyl)-4,4′-bipyridine dichloride, CH2O = formaldehyde), and {CuII(1,1-pmbby)2(H2O)[H2(β-Mo8O26)2]}·5H2O·C2H7N (4) (1,1-pmbby·2Cl = 1,1′-[1,4-phenylbis(methylene)]bis-(4,4′-bipyridine)dichloride, C2H7N = dimethylamine). These four compounds exhibit different fascinating structures, especially compound 4 is a typical metal–organic framework. Compounds 1–4 exhibit good discoloration behaviors under various external stimuli. For example, compounds 1–4 showed a positive response to the irradiation from a 300 W Xe lamp. When a positive voltage was applied to the ECD based on compounds 1–4, 1/2/3/4-ECD underwent a significant color conversion. What's more, compound 4 also showed obvious discoloration results after heating. In a word, 1–4 are multifunctional discoloration materials under different external stimuli. In addition, the coated filter paper prepared based on compound 3 can be used as a new printing material medium and can be successfully applied in erasable inkless printing and dual anti-counterfeiting. [ABSTRACT FROM AUTHOR]

In 2014, the Hazelwood mine fire burned for 45 days. Local communities were impacted by smoke and ash, and there were reports of raised carbon monoxide levels. Local news and social media reported residents experiencing numerous physical symptoms of smoke inhalation, including bleeding noses, coughing, wheezing and chest tightness. Paper masks to filter particulate matter were made available to residents to wear outside. The dust and ash constantly seeped into homes and offices, which required cleaning daily and sometimes multiple times during the day. Smoke was free to move across physical and bodily boundaries while those most vulnerable were hampered by lack of movement: pregnant women, the elderly and children were advised to leave the area. However, this suggestion to 'simply' move ignored the context of a community disproportionately impacted through years of economic decline and societal change. This paper explores the unequal mobilities of smoke and people that arose as a result of this event and draws on concepts of mobility justice (Sheller 2018) and emergency mobilities (Adey 2016) to reflect on the political dimensions of uneven mobility in times of crisis. [ABSTRACT FROM AUTHOR]

Although membrane separation technology has been widely used in the treatment of oily wastewater, the complexity and high cost of the membrane preparation, as well as its poor stability, limit its further development. In this study, via the vacuum-assisted suction filtration method, polydopamine (PDA)-coated TiO2 nanoparticles were tightly attached and embedded on both sides of laboratory filter paper (FP). The resultant FP possessed the typical wettability of high hydrophilicity in the air with the water contact angle (WCA) of 28°, superoleophilicity with the oil contact angle (OCA) close to 0°, underwater superoleophobicity with the underwater OCA greater than 150°, and superhydrophobicity under the water with the underoil WCA over 150° for five kinds of organic solvents (carbon tetrachloride, toluene, n-hexane, n-octane, and iso-octane). The separation efficiency of immiscible oil/water, oil-in-water, and water-in-oil emulsions using the modified FP is higher than 99%. After 17 cycles of emulsion separation, a high separation efficiency of 99% was still maintained for the FP, along with good chemical and mechanical stability. In addition, successful separation and purification were also realized for the oil-in-water emulsion that contained the methylene blue (MB) dye, along with the complete degradation of MB in an aqueous solution under UV irradiation. [ABSTRACT FROM AUTHOR]

Measuring energy balance and energy metabolism can provide crucial information for understanding the ecological and behavioral drivers of an animal's energetic and physiological condition. Both urinary C‐peptide (uCP) of insulin and urinary total triiodothyronine (uTT3) have been validated as noninvasive biomarkers of energy balance and metabolic activity in haplorrhine primates. This study attempts to validate uCP and uTT3 measures in strepsirrhines, a phylogenetically distinct primate clade, using the ruffed lemur (genus Varecia) as a model. We experimentally manipulated the diet of captive black‐and‐white (Varecia variegata) and red (Varecia rubra) ruffed lemurs at Duke Lemur Center across a 4‐week period. We collected urine samples from subjects (n = 5) each day during 1 week of control diet, 2 weeks of calorie‐restricted diet and 1 week of refeeding, designed to temporarily reduce energy balance and metabolism. We also tested the outcome of filter paper as a storage method by comparing to controls (frozen at −20°C) to assess its suitability for studies of wild populations. We successfully measured uCP and uTT3 levels in frozen urine samples using commercial enzyme immunoassay kits and found that both biomarkers were excreted at lower concentrations (C‐peptide: 1.35 ng/mL, 54% reduction; TT3: 1.5 ng/mL, 37.5% reduction) during calorie‐restricted periods compared to normal diet periods. Filter paper recovery for uCP was 19%, though values were significantly positively correlated with frozen control samples. uTT3 could not be recovered at measurable concentrations using filter paper. These methods enable noninvasive measurement of energetic conditions in wild strepsirrhines and subsequent assessment of relationships between energy balance and numerous socioecological drivers in primate populations. HIGHLIGHTS: Both C‐peptide (CP) and total triiodothyronine (TT3) are measurable in lemur urine using commercial enzyme immunoassays.Concentrations of both metabolites decrease when animals are subjected to caloric restriction.Both metabolites can be measured when stored at −20°C, whereas filter paper is a viable storage option only for CP and not triiodothyronine. [ABSTRACT FROM AUTHOR]

Mudstone soils (MS) are widely distributed in southern Taiwan and have an inherent proclivity to geological damages and failures. However, the use of traditional and non-traditional techniques to treat MS remains a challenge and is an area relatively unexplored due to the soils' distinct and sophisticated features. This study examined the hydromechanical performance of reconstituted MS treated with colloidal nanosilica (CN), fiber (f), and combinations thereof (CN-f) via a series of laboratory tests, including the unconfined compressive strength tests, 3D volumetric shrinkage tests, free swell tests, 1D consolidation tests, and filter paper tests. Fourier-transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM) were also used to inspect the geochemical composition and microstructure of the untreated and treated MS. Results suggest that CN-f treatment can significantly improve the peak and postpeak strengths and ductility of MS while achieving satisfactory improvements in swelling control, shrinkage limits, and volumetric strains. Following treatment with 15% CN and 1% f for 28 days, the MS showed an optimal 527% improvement in Unconfined compressive strength (UCS) and satisfactory residual strain. Finally, the FTIR and SEM images revealed enhanced interlocking between the MS particles and the formation of marginal C–S–H and viscous gels, supporting the improved performance in MS. This study provides comprehensive analyses that offer insights into the synergistic effects of CN-f on the hydromechanical performance of MS. The findings will be valuable to engineers exploring innovative and ecofriendly alternatives for treating MS with a robust design. [ABSTRACT FROM AUTHOR]

Background: Clinical and laboratory diagnosis of cutaneous leishmaniasis (CL) is hampered by under-ascertainment of direct microscopy. Methods: This study compared the diagnostic accuracy of qPCR on DNA extracted from filter paper to the accuracy of direct smear slide microscopy in participants presenting with a cutaneous lesion suspected of leishmaniasis to 16 rural healthcare centers in the Ecuadorian Amazon and Pacific regions, from January 2019 to June 2021. We used Bayesian latent class analysis to estimate test sensitivity, specificity, likelihood ratios (LR), and predictive values (PV) with their 95% credible intervals (95%CrI). The impact of sociodemographic and clinical characteristics on predictive values was assessed as a secondary objective. Results: Of 320 initially included participants, paired valid test results were available and included in the diagnostic accuracy analysis for 129 from the Amazon and 185 from the Pacific region. We estimated sensitivity of 68% (95%CrI 49% to 82%) and 73% (95%CrI 73% to 83%) for qPCR, and 51% (95%CrI 36% to 66%) and 76% (95%CrI 65% to 86%) for microscopy in the Amazon and Pacific region, respectively. In the Amazon, with an estimated disease prevalence among participants of 73%, negative PV for qPCR was 54% (95%CrI 5% to 77%) and 44% (95%CrI 4% to 65%) for microscopy. In the Pacific, (prevalence 88%) the negative PV was 34% (95%CrI 3% to 58%) and 37% (95%CrI 3% to 63%). The addition of qPCR parallel to microscopy in the Amazon increases the observed prevalence from 38% to 64% (+26 (95%CrI 19 to 34) percentage points). Conclusion: The accuracy of either qPCR on DNA extracted from filter paper or microscopy for CL diagnosis as a stand-alone test seems to be unsatisfactory and region-dependent. We recommend further studies to confirm the clinically relevant increment found in the diagnostic yield due to the addition of qPCR. Author summary: Cutaneous leishmaniasis is caused by the parasite Leishmania and is treated when a microscopy test confirms the presence of the parasite in a sample of the lesion. This test, however, is known to miss patients with cutaneous leishmaniasis. DNA diagnostic tests (like PCR) that detect the parasite's genetic material in the lesion, have been proposed to improve diagnosis. Filter paper preserves DNA at room temperature and allows samples to be transported from remote health centers to the PCR laboratory. The ability of microscopic and DNA testing to recognize leishmaniasis patients in real-life is complex to evaluate. We compared the performance of both tests using a statistical method that can evaluate both tests simultaneously without assuming that either test works perfectly. We found that PCR will be positive 68% of the time in a participant with leishmaniasis in the Amazon and 73% of the time in the Pacific region. In the Amazon, microscopy detects one out of every two cases, while it does in three out of every four cases in the Pacific. The addition of the PCR test can improve the number of participants with a diagnosis of leishmaniasis, mostly in the Amazon region. [ABSTRACT FROM AUTHOR]

Rapid and accurate bioburden detection has become increasingly necessary for food, health, pharmaceutical and environmental applications. To detect bioburden accurately, and in a highly sensitive manner, we have fabricated a novel microfluidic device with an integrated filter to trap the cells. Bioburden is detected on the filter paper in situ using the redox reaction of fluorescent label resorufin and a portable multichannel fluorometer is used for fluorescence measurement. The microfluidic device was fabricated in a facile, low-cost, and rapid way with microwave-induced thermally assisted bonding. To characterize the bonding quality of the microfluidic cassettes, different tests were performed, and the filter paper material and size were optimized. Primary Bacillus subtilis culture bacterial samples were filtered through the device to validate and investigate the performance parameters. Our results show that a limit of detection (LOD) of 0.037 CFU/mL can be achieved through this microfluidic device whereas the LOD in a normal microfluidic cassette in the fluorometer and the golden standard spectrophotometer are 0.378 and 0.128 CFU/mL respectively. The results depict that three to ten times LOD improvement is possible through this microfluidic cassette and more sensitive detection is possible depending on the volume filtered within a rapid 3 min. This novel microfluidic device along with the fluorometer can be used as a rapid portable tool for highly sensitive, accurate and high-throughput bacterial detection for different applications. [ABSTRACT FROM AUTHOR]

As one of the most common forms of waste, waste PET is a serious pollutant in natural and human living environments. There is an urgent need to recycle PET. For this study, the complete degradation of PET was realized at a low temperature. A lipophilic hydrophobic membrane was formed on the surface of a stainless steel mesh (SSM) using a simple dip coating method, and an oil–water separation material was successfully prepared. After loading with degradation products, the surface roughness of SSM increased from 19.09 μm to 62.33 μm. The surface changed from hydrophilic to hydrophobic, and the water contact angle increased to 123°. The oil–water separation flux of the modified SSM was 9825 L/(m2·h), and the separation efficiency was 98.99%. The modified SSM had good reuse performance. This hydrophobic modification method can also be used to modify other porous substrates, such as activated carbon, filter paper, foam, and other materials. The porous substrate modified by the degradation product of waste PET was used to prepare oil–water separation materials, not only solving the problem of white pollution but also reducing the dependence on non-renewable resources in the conventional methods used for the preparation of oil–water separation materials. This study provides new raw materials and methods for the industrial production of oil–water separation materials, which have important application prospects. [ABSTRACT FROM AUTHOR]

A luminescent trimethylamine (TMA) sensor, PTMA-Ir, has been designed and synthesized through immobilizing a phosphorescent iridium(III) complex on a TMA-imprinted polymer. Detailed study shows that the quenching of phosphorescence of PTMA-Ir can serve as a reporter for the binding of TMA on the imprinting sites, thus providing a sensitive, selective, and rapid detection of TMA in both aqueous solutions and gaseous states. Loading PTMA-Ir on filter paper produced a deposition T-Ir, the phosphorescence of which is quenched within 5 s upon exposure to TMA vapor with detection limits of 9.0 ± 0.1 ppm under argon and 15.0 ± 0.1 ppm in an air atmosphere. This work provided an effective method for establishing an imprinting polymer-immobilized luminescent amine sensor. [ABSTRACT FROM AUTHOR]

BACKGROUND: Flexible surface‐enhanced Raman spectroscopy (SERS) substrates such as paper‐based substrates show great potential for rapid detection of residual chemicals on food surfaces. However, controlling the density and distribution of metallic nanoparticles adsorbed on the paper is still challenging. RESULTS: The amount of gold (Au) nanospheres (51 ± 4 nm) attached on the filter paper modified with 3‐aminopropyltriethoxysilane (APTES) was tunable, increasing as the level of APTES (2.5–15.0 g kg−1) applied for paper modification increased. Moreover, the Au nanospheres were relative evenly distributed on the filter paper modified with 2.5–10.0 g kg−1of APTES, which resulted in excellent intra‐ and inter‐reproducibility of SERS signals for pesticides including thiram, diquat dibromide, and paraquat dichloride (relative standard deviation = 2.2–10.1%). The modified paper‐based substrate could be used to detect as low as 0.05–0.2 mg L−1 of pesticides in standard solutions, and as low as 5–20 ng cm−2 of residual pesticides on apple skins with minimum sample pretreatment. CONCLUSION: This paper‐based substrate with tunable feature for the density and distribution of nanoparticles is applicable for rapid SERS detection of residual pesticides in fruits and vegetables. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Introduction: Percutaneous drug delivery systems are attractive not only as a therapeutic strategy but also for cosmetic treatment. Iontophoresis is a well-recognized method for promoting transdermal absorption of ionized compounds. Franz cells are generally used to estimate drug permeation of skin by iontophoresis. However, methods using Franz cells are less versatile; for instance, the method is unsuited for use with a portable electric facial care device having a working probe of a certain size and weight. In this study, we constructed a semi-dry apparatus for use with an electric facial care device. Methods: The apparatus has a multilayer structure consisting of mouse skin and 3 filter papers, modeled after the Franz cell. The skin permeation of the drug edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) was then measured using this apparatus. Results: Edaravone permeation depended on working time, drug concentration, and ionization ratio of edaravone when iontophoresis was carried out with an electric facial care device. Furthermore, glycyrrhizic acid, α-tocopheryl phosphate, retinoic acid, and ascorbyl palmitate, which are recognized as functional cosmetic materials, also permeated the skin by applying iontophoresis with the device. Conclusion: These results suggest that the developed measuring apparatus is applicable for use with a portable electric facial care device and that iontophoresis using a portable electric facial care device is potentially useful in the cosmetic field. [ABSTRACT FROM AUTHOR]

Polarimetric Synthetic Aperture Radar (PolSAR) data is inherently characterized by speckle noise, which significantly deteriorates certain aspects of the quality of the PolSAR data processing, including the polarimetric decomposition and target interpretation. With the rapid increase in PolSAR resolution, SAR images in complex natural and artificial scenes exhibit non-homogeneous characteristics, which creates an urgent demand for high-resolution PolSAR filters. To address these issues, a new adaptive PolSAR filter based on joint similarity measure criterion (JSMC) is proposed in this paper. Firstly, a scale-adaptive filtering window is established in order to preserve the texture structure based on a multi-directional ratio edge detector. Secondly, the JSMC is proposed in order to accurately select homogeneous pixels; it describes pixel similarity based on both space distance and polarimetric distance. Thirdly, the homogeneous pixels are filtered based on statistical averaging. Finally, the airborne and spaceborne real data experiment results validate the effectiveness of our proposed method. Compared with other filters, the filter proposed in this paper provides a better outcome for PolSAR data in speckle suppression, edge texture, and the preservation of polarimetric properties. [ABSTRACT FROM AUTHOR]

Dry blood spots, appear to be a valuable option for sample collection for DNA extraction, especially in poorer communities with less access to medical care. Dry blood spots can be easily transported and ensure a non-invasive method of rapid blood collection which can be coupled with DNA extraction methods. However, the storage and transportation conditions (time and temperature) as well as sample type and volumes may affect DNA extraction efficiency and become a challenge. In this context, we aim to assess the effects on DNA extraction efficiency of six storage conditions (24 hours at 4 °C, 24 hours at room temperature, 24 hours at 50 °C, seven days at 4 °C, seven days at room temperature, and seven days at 50 °C) for dry blood spots with venous blood and capillary blood samples. In order to evaluate DNA extraction proficiency, under each of these conditions, we performed DNA extraction with the QIAamp® Blood Mini Kit and assessed DNA final concentrations and purity ratios, through UV spectrophotometry, with the aid of the Nanodrop® OneC. Statistical analysis was performed using a T-test in Microsoft® Excel. Overall, our data demonstrated that it is possible to extract a greater DNA quantity from capillary blood samples in dry blood spots, although with less purity than venous blood samples. Also, our results show that the assessed temperature and storage time (seven days) do not affect DNA extraction results. [ABSTRACT FROM AUTHOR]

Objective: To determine the accuracy of high‐risk human papillomavirus (HPV) DNA samples on filter paper in comparison to specimen transport medium (STM). Methods: This was a cross‐sectional diagnostic study of 42 consecutive women who were prospectively recruited. Each had self‐collected vaginal samples on filter paper, physician‐collected cervical samples on filter paper, and physician‐collected cervical samples in STM. HPV DNA testing was performed with a Hybrid Capture 2 system (Qiagen). Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and agreement of filter paper methods with the standard procedure were calculated. Results: The overall prevalence of HPV in STM was 67.5%. Detection of HPV DNA in the physician‐collected cervical samples on filter paper had a sensitivity of 77.8%, a specificity of 100%, a PPV of 100%, and an NPV of 68.4%. The patient's self‐sampling on filter paper had a sensitivity of 66.7%, a specificity of 100%, a PPV of 100%, and an NPV of 59.1%. The agreement between STM method and physician‐collected sample on filter paper was substantial, (κ = 0.695, P < 0.001), while the agreement between STM and self‐collected samples on filter paper was moderate (κ = 0.565, P < 0.001). Most patients reported that self‐collection was acceptable (100%), painless (95%), and not embarrassing (95%). Conclusion: Filter paper, with dried self‐collected vaginal samples, can be used to detect high‐risk HPV with acceptable accuracy. Synopsis: Self‐collected vaginal samples on filter paper, to detect high‐risk human papillomavirus, is better for women, easier to transport to central laboratories, and has acceptable accuracy. [ABSTRACT FROM AUTHOR]

An abundance of refractory cellulose is the key limiting factor restricting the resource utilization efficiency of silkworm (Bombyx mori) excrement via composting. Screening for cellulose-degrading bacteria is likely to provide high-quality strains for the safe and rapid decomposition of silkworm excrement. In this study, bacteria capable of degrading cellulose with a high efficiency were isolated from silkworm excrement and the conditions for cellulase production were optimized. The strains were preliminarily screened via sodium carboxymethyl cellulose culture and staining with Congo red, rescreened via a filter paper enzyme activity test, and identified via morphological observation, physiological and biochemical tests, and phylogenetic analysis of the 16S rDNA sequence. Enzyme activity assay was performed using the 3,5-dinitrosalicylic acid method. DC-11, a highly cellulolytic strain, was identified as Bacillus subtilis. The optimum temperature and pH of this strain were 55 °C and 6, respectively, and the filter paper enzyme activity (FPase), endoglucanase activity (CMCase), and exoglucanase activity (CXase) reached 15.40 U/mL, 11.91 U/mL, and 20.61 U/mL. In addition, the cellulose degradation rate of the treatment group treated with DC-11 was 39.57% in the bioaugmentation test, which was significantly higher than that of the control group without DC-11 (10.01%). Strain DC-11 was shown to be an acid-resistant and heat-resistant cellulose-degrading strain, with high cellulase activity. This strain can exert a bioaugmentation effect on cellulose degradation and has the potential for use in preparing microbial inocula that can be applied for the safe and rapid composting of silkworm excrement. [ABSTRACT FROM AUTHOR]

As acetonitrile is a widely used solvent for the chemical industry, the recovery of acetonitrile from acetonitrile wastewater is significant for both industrial cost reduction and environmental protection. In this article, a simple, low‐energy, and low‐cost strategy is proposed for the effective separation of acetonitrile from high‐concentration acetonitrile wastewater. The approach is based on a sequential combination of two steps: salt‐induced phase separation and hydrophobic filtration. The acetonitrile wastewater was first induced to split into two phases by salt, that is, the acetonitrile‐rich phase and the water‐rich phase, then the above two phases were poured into the hydrophobic filter paper funnel for the separation. It was shown that NaCl is a suitable salting‐out reagent, and that hydrophobic filter papers—obtained from modification by butyltrichlorosilane and octyltrichlorosilane were the optimal choice for hydrophobic filtration. The salt‐induced phase separation process is able to increase the volume fraction of acetonitrile in the acetonitrile‐rich phase up to 92%. The acetonitrile‐rich phase can pass through the hydrophobic filter paper, whereas the water‐rich phase was intercepted. The hydrophobic filter paper retained strong hydrophobicity and high acetonitrile‐separating capacity after 3 months storage, or upon immersion in acetonitrile‐water mixtures for 12 h, or applied for 25 consecutive separations. [ABSTRACT FROM AUTHOR]