Filter Unit Research Articles

Black Carbon and Particulate Matter Concentrations: Air Pollution Levels in Rio de Janeiro, Brazil

This research explores the concentration of black carbon (BC) in particulate matter (PM10 and PM2.5) from ten monitoring stations in the Metropolitan Region of Rio de Janeiro (MRRJ), Bonsucesso (BS), Botafogo (BOT), Copacabana (COP), Gavea (GAV), Gericino (GER), Lagoa (LAG), Recreio dos Bandeirantes (REC), Santa Cruz (SC), Castelo (CAS) and Urca (URC), covering a range of pollution sources (vehicular, industrial, and residential). PM samples were collected using filter units every week from January 2018 to December 2019. Results revealed high concentrations of PM10 in BS (86 ± 22 µg m-3) and PM2.5 in REC (30 ± 11 µg m-3). Likewise, both monitoring stations exceeded the international limits. In 2019, BC in PM10 decreased in the following order: BS > CAS > GER > BOT > SC > GAV. For 2018, BC in PM2.5 decreased as follows REC > LAG > SC, while 2019 REC > GAV > LAG > COP > URC. REC and BS have industrial and commercial activities and intense vehicular traffic. During the period of study, average BC concentrations in PM10 and PM2.5 were 3.3 ± 1.5 and 1.9 ± 0.70 µg m-3, respectively. These findings indicate that BC concentrations should be monitored and regulated in locations with high levels of traffic-related air pollution for offering new insights and guiding efforts to minimize emissions and enhance public health.

Evaluation of the effectiveness of various pollution removal mechanisms of indoor air purifiers in removing suspended particles

This study comprehensively investigated the efficacy of five distinct air purifiers in the removal of both particulate matter and gaseous pollutants. The analysis was conducted within a consistent test environment, employing a standardized benchmark to ensure accurate and comparable results. A rigorous methodology was devised to evaluate the efficiency of each air purification mechanism. The experimental setup involved placing the air purifiers inside a controlled test chamber, carefully designed to replicate typical indoor conditions. The focus of the analysis was on the removal efficiency of PM2.5, and the evaluation utilized the Clean Air Delivery Rate (CADR) values, measured in cubic feet per minute (ft³/min or CFM). Importantly, the study maintained uniform specifications, including unit filter area and unit electrostatic volume, to facilitate a fair and meaningful comparison of the removal efficiency for each purification mechanism. The CADR values served as a quantitative metric to assess the air purifiers’ effectiveness in removing PM2.5 particles. This standardized approach allowed for a direct comparison of their performance under identical conditions. By considering unit filter area and electrostatic volume, the study aimed to provide insights into the relative merits of each mechanism, enabling consumers to make informed decisions based on the specific removal capabilities of the air purifiers. In summary, the research established a robust methodology for evaluating air purifier performance, facilitating a thorough analysis of their effectiveness in removing particulate matter and gaseous pollutants within a controlled environment. The use of CADR values and standardized specifications ensures a reliable basis for comparing the efficiency of different air purification mechanisms.

Miniaturized Filter Unit Based on Serpentine Microstrip Resonator and Half-mode Substrate Integrated Waveguide and Its Application

Miniaturized Filter Unit Based on Serpentine Microstrip Resonator and Half-mode Substrate Integrated Waveguide and Its Application

The Effects of Intake Water Quality and Filtration Unit Performance on the Efficiency of the Al- Rasheed Water Treatment Plant in Baghdad, Iraq

The Effects of Intake Water Quality and Filtration Unit Performance on the Efficiency of the Al- Rasheed Water Treatment Plant in Baghdad, Iraq

Enhancing the dewatering of oil sands mature fine tailings by coagulation-flocculation and pressure filtration with tannic acid-mediated polymeric complex network

This study presents a new method to improve the dewatering efficiency of oil sands mature fine tailings (MFT) by pressure filtration using a tannic acid-mediated polymeric complex network as a flocculant. It was found that the prior addition of tannic acid ahead of poly(ethylene oxide) and ferric chloride significantly increased the vacuum filtration rate by improving the permeability of the filter cake and reducing its specific resistance to filtration. The beneficial role of tannic acid was investigated by slurry shear stress, sedimentation, floc morphology and size distribution measurements, and UV–Vis and FTIR spectroscopic characterization. Results indicated that tannic acid acted as a crosslinker to complex with both poly(ethylene oxide) and ferric chloride to develop a tri-component polymeric network. Within the network, numerous hydrogen bonds and coordination bonds enabled a sufficient crosslinking density, resulting in higher floc strength and compression resistance. Flocs generated by the tannic acid-mediated polymeric network were more rigid with an expanded structure, allowing drainage channels to remain open in the filter cake for better permeability. Scale-up experiments on a Millipore pressure filtration unit verified the beneficial role of tannic acid in filtering the mature fine tailings, achieving a much higher net water release rate and cake solid content.

Assessing operational issues in a modular sewage treatment plant and providing remedies via comprehensive modeling and simulation through GPS-X

In this study, an existing but faulty modular sewage treatment plant (STP) with a capacity of 100 m3/day has been modeled and assessed using GPS-X software, combined with sensitivity analysis to confirm an underlying but critical operational issue of an STP. Currently, the STP shows <5 % ammonia removal at an average influent ammonia concentration of 50 mg/L, along with the problem of partial BOD removal. The treatment units comprise an equalization tank, two moving bed biofilm reactors (MBBRs) in series, a tube settler and a sand filtration unit. Sensitivity analysis helped decipher the most influential kinetics/stoichiometric parameters, which assisted in achieving a precise model calibration. Post calibration, the modified model was re-simulated for each constituent treatment unit based on the mass balance of four major output parameters viz. NH4-N, biochemical oxygen demand, dissolved oxygen and alkalinity. Real experimental/measured values spanning over 8 months were analyzed during the calibration phases (including both static and dynamic calibration phases). The calibrated GPS-X model was simulated using various input factors to find a possible remedial solution and understand the critical limitation of the existing plant. As a remedial measure, a pre-anoxic tank with an operational volume of 15 m3 and a recirculation ratio of 3 was proposed for the existing STP. A proper experimental design and statistical tools further helped achieve the most optimum and techno-economically feasible solution for an MBBR-based biological treatment unit. This helped effectively manage wastewater pollution in a modular treatment system.

Reduction of Outdoor and Indoor PM2.5 Source Contributions via Portable Air Filtration Systems in a Senior Residential Facility in Detroit, Michigan.

Background: The Reducing Air Pollution in Detroit Intervention Study (RAPIDS) was designed to evaluate cardiovascular health benefits and personal fine particulate matter (particulate matter < 2.5 μm in diameter, PM2.5) exposure reductions via portable air filtration units (PAFs) among older adults in Detroit, Michigan. This double-blind randomized crossover intervention study has shown that, compared to sham, air filtration for 3 days decreased 3-day average brachial systolic blood pressure by 3.2 mmHg. The results also showed that commercially available HEPA-type and true HEPA PAFs mitigated median indoor PM2.5 concentrations by 58% and 65%, respectively. However, to our knowledge, no health intervention study in which a significant positive health effect was observed has also evaluated how outdoor and indoor PM2.5 sources impacted the subjects. With that in mind, detailed characterization of outdoor and indoor PM2.5 samples collected during this study and a source apportionment analysis of those samples using a positive matrix factorization model were completed. The aims of this most recent work were to characterize the indoor and outdoor sources of the PM2.5 this community was exposed to and to assess how effectively commercially available HEPA-type and true HEPA PAFs were able to reduce indoor and outdoor PM2.5 source contributions. Methods: Approximately 24 h daily indoor and outdoor PM2.5 samples were collected on Teflon and Quartz filters from the apartments of 40 study subjects during each 3-day intervention period. These filters were analyzed for mass, carbon, and trace elements. Environmental Protection Agency Positive Matrix Factorization (PMF) 5.0 was utilized to determine major emission sources that contributed to the outdoor and indoor PM2.5 levels during this study. Results: The major sources of outdoor PM2.5 were secondary aerosols (28%), traffic/urban dust (24%), iron/steel industries (15%), sewage/municipal incineration (10%), and oil combustion/refinery (6%). The major sources of indoor PM2.5 were organic compounds (45%), traffic + sewage/municipal incineration (14%), secondary aerosols (13%), smoking (7%), and urban dust (2%). Infiltration of outdoor PM2.5 for sham, HEPA-type, and true HEPA air filtration was 79 ± 24%, 61 ± 32%, and 51 ± 34%, respectively. Conclusions: The results from our study showed that intervention with PAFs was able to significantly decrease indoor PM2.5 derived from outdoor and indoor PM2.5 sources. The PAFs were also able to significantly reduce the infiltration of outdoor PM2.5. The results of this study provide insights into what types of major PM2.5 sources this community is exposed to and what degree of air quality and systolic blood pressure improvements are possible through the use of commercially available PAFs in a real-world setting.

Implementation of an automated process for Limnospira indica harvesting and culture medium recycling for space applications

Future long-term space exploration missions require the implementation of circular life support systems for the supply of water, oxygen and food from mission wastes. Therefore, separation systems dealing with multi-phasic streams need to be addressed. The BioHarvest (BHV) study focused on solid/liquid separation in space with the aim to demonstrate the continuous separation and harvesting of the cyanobacterium Limnospira indica from its culture broth under axenic conditions. The cyanobacterium biomass is intended to be used for further food processing while the broth free of organic matter and resupplied with nutrients should be directly recycled into the photobioreactor (PBR). In this study, an automated breadboard model based on a two-step process was built. First, a Biomass Harvesting Unit (BHU) separates the biomass produced in the PBR from the culture medium with dead-end filtration. Second, the Medium Filtration Unit (MFU) further treats the culture medium to retain the dissolved organic compounds using crossflow filtration. The performances of BHU and MHU met the requirements in batch mode and in short continuous mode: the BHU was able to retain all the biomass and the MFU could retain more than 90% of organic matter while being permeable to nutrients. The productivity of the MFU was also very good, with a high permeation flux allowing treating the targeted 80 L of culture per day. However, continuous operation of the BHV technology could not be achieved in the long term due to biomass accumulation as a sticky cake with a high specific resistance on the BHU filter, despite backwashing cycles and intense vibrations. Future work shall therefore focus on this critical step, to improve process performance by preventing fouling of the filter sheets.

Calculation of CO2 generation and required fresh air rates in a high-intensity physical athletic facility

Recently, there has been a significant growth in the number of athletic facilities associated with the progressive demand of people trying to reverse the increasingly sedentary lifestyle of current society. Cross-training facilities have become more popular in recent years among these training centers. Therefore, a detailed investigation of their indoor air quality (IAQ) is required to ensure a healthy environment for their occupants. In this study, we evaluated the IAQ of a cross-training facility in San Antonio, Texas, USA, for four days in January 2022. Each day was associated with a different air ventilation scenario involving the use of ceiling fans and an air filtration unit during the training sessions. Data from carbon dioxide (CO2) and particulate matter (PM) concentrations have been gathered for 24 h in 5-min intervals for high-intensity physical activity, such as cross-training workouts, and subsequently analyzed. CO2 concentration has been used to obtain both the infiltration rate of the building using the tracer gas decay method, and the CO2 generation rate, providing reference values as a function of the occupancy for different workout sessions. The applied methodology can be used to calculate the required volumetric fresh air flow rate to ensure a healthy environment regarding CO2 concentration in athletic facilities. In particular, the fresh air necessary rates obtained for the cross-training sessions are higher than the ones associated with sedentary activities. Finally, the deposition rate of PM from 0.3 to 10 μm has been calculated, including those potentially harmful to humans, namely PM2.5, PM5, and PM10.

MicroRNA193a: An Emerging Mediator of Glomerular Diseases.

MicroRNAs (miRNAs) are noncoding small RNAs that regulate the protein expression of coding messenger RNAs. They are used as biomarkers to aid in diagnosing, prognosticating, and surveillance of diseases, especially solid cancers. MiR-193a was shown to be directly pathogenic in an experimental mouse model of focal segmental glomerulosclerosis (FSGS) during the last decade. Its specific binding and downregulation of Wilm's tumor-1 (WT-1), a transcription factor regulating podocyte phenotype, is documented. Also, miR-193a is a regulator switch causing the transdifferentiation of glomerular parietal epithelial cells to a podocyte phenotype in in vitro study. Interaction between miR-193a and apolipoprotein 1 (APOL1) mRNA in glomeruli (filtration units of kidneys) is potentially involved in the pathogenesis of common glomerular diseases. Since the last decade, there has been an increasing interest in the role of miR-193a in glomerular diseases, including diabetic nephropathy and membranous nephropathy, besides FSGS. Considering the lack of biomarkers to manage FSGS and diabetic nephropathy clinically, it is worthwhile to invest in evaluating miR-193a in the pathogenesis of these diseases. What causes the upregulation of miR-193a in FSGS and how the mechanism is different in different glomerular disorders still need to be elucidated. This narrative review highlights the pathogenic mechanisms of miR-193a elevation in various glomerular diseases and its potential use in clinical management.

A Comprehensive Study of Variation in Water Quality Parameters to Design a Sustainable Treatment Plant

In this paper, greywater samples are collected from the kitchens of different types of buildings (residential and commercial) located in different districts within the city of Jeddah, Saudi Arabia. The collected samples are analyzed and compared with the potable water from the same region. The parameters investigated are pH, conductivity, total solids (TS), total dissolved solids (TDS), total suspended solids (TSS), total hardness, temporary hardness, permanent hardness, alkalinity, chloride, and biochemical oxygen demand (BOD). It was found that the amount of total suspended solids is very high in the greywater samples. It shows the presence of both temporary and permanent hardness. Their alkalinity values are greater than hardness. It may be due to the number, lifestyle, age of the occupants, presence of children, and social and cultural behavior of residents. The concentration of BOD level is very low, which shows that the greywater samples have lower concentrations of organic compounds. Design details of the greywater treatment plant are suggested based on the results of the analysis. This includes a screening chamber, grit chamber, settling tank, and filtration unit. The treated greywater is recommended for reuse for gardening, landscaping, and toilet flushing purposes.

Optimal design of silver-loaded zeolite filter structure based on porous media model

Silver zeolite filters have potential applications in nuclear power plant filtration and emission systems due to their high-efficiency adsorption properties for radioactive methyl iodide. The adsorption performance of the filter is closely related to the flow distribution characteristics. To analyze the flow distribution characteristics of the filter element, we established a reasonable numerical calculation model and verified the model through experiments. Then based on the model, the advantages and disadvantages of different filter unit structures are analyzed. We proposed two new structural forms of filters and evaluated the performance of the filters based on the pressure distribution and flow increment curve, considering the difficulty of processing and space utilization. Comparative analysis and characteristic research have been carried out under different sizes, from the cylindrical filter to the round table filter and, finally, to the square filter. Our results show that round table and square filters have significantly improved flow distribution compared to traditional cylindrical filters. However, the structure of the round table filter is irregular, and the space utilization rate is low. Finally, through optimization design, the square filter with channel spacing L of 250 mm has the best performance. Our research results have a certain guiding significance for the design of the silver zeolite filter prototype.

Effect of Aquatic Plants as a Biofilter on Water Criteria and Common Carp Growth Performance in Aquaculture Intensive System

The experiment was conducted in the field of the College of Agriculture, University of Tikrit, for the period from 14/6/2022 to 14/8/2022 inside a semi-exposed building (gable) with four treatments. Each treatment included three replicates, and each replicate included (6) fishes in a closed bio-aquatic system, by weight 14.15±1.22, 13.8±0.72,13.9±0.78, 13.7±0.93g for T1, T2, T3 and T4 in 12 ponds respectively. On a filtration tank representing the biological and mechanical filter in an intensive aquatic system with a capacity of 100 liters each, three aquatic plants were grown (lentils, Azolla, Ceratophylom), except for the control treatment, which was similar to all treatments except for the presence of aquatic plants. The water was treated in a mechanical filter unit through thick sponge layer, then directing the water to the biological treatment by means of crushed gravel, in addition to the aquatic plants to filter the dissolved organic pollutants. The results showed a significant effect of aquatic plants at (p ≤0.05) on dissolved oxygen DO (mg / liter), pH, total dissolved salts (TDS), nitrate NO3, nitrite NO2, and ammonia. The biological characteristics of aquatic plants are impacted by modifications to the physicochemical properties of the water. There was a significant improvement in weight gain (G.W), relative growth (RGR), specific growth of fish (SGR), and feed conversion efficiency (FCR) for treatments T2, T3, and T4 compared with control treatment. There was a significant difference when using aquatic plant in the percentage of protein compared to the control treatment. No significant differences were observed on blood biochemical parameters. While the result of the correlation or interactions between water characteristics with growth parameters for Common carp fish showed significant effects at a significant level (P ≤0.05) and (P ≤0.01).

Survey of undesirable noises in an industrial clean room

In industrial clean rooms, air conditioning systems and other necessary equipment are a constant source of noise. Out of the three clean rooms (X, Y, and Z) managed by us, Room X had particularly annoying noise levels, and required investigation. In this study, surveys are performed to determine how the noise can be minimized: the facilities in each room are investigated, the working environment and personal noise exposure are measured, the noise sources are subjected to frequency analysis, and hearing tools are evaluated to reduce annoyance among clean-room users. The measurement results show that the noise level in room X was more than 5 dB higher than that in rooms Y and Z. The frequency analysis results show that the dominant frequency spectrum of the fan filter unit (FFU) operating noise is around 100 Hz, and that of the air blowing noise is in the high frequency range above 10 kHz. Finally, hearing tools (noise-canceling earphone and earplugs) are distributed to workers in Room X, who rank their effectiveness. The results show that noise-canceling earphones are preferred, although no statistically significant differences are obtained. Consequently, the work environment is effectively improved.

High‐Resolution 2D Quasi‐Distributed Optical Sensing with On‐Chip Multiplexed FSR‐Free Nanobeam Cavity Array

AbstractOn‐chip free spectral range (FSR)‐free optical filter with a compact footprint is crucial for developing emerging sensing applications, as it allows for the optimal utilization of extensive optical bandwidth. Despite being an important area of technology, on‐chip optical sensing system has faced challenges in channel count, particularly due to the limited FSR, large footprint, and loss of the wavelength‐selective filter unit. To address these challenges, a scalable nanobeam cavity prototype with a length of ≈21 µm based on the asymmetric Bragg mirrors is presented. By engineering the band structure of the nanobeam cavity, the stopband can be flexibly tuned to achieve an FSR‐free spectral response within 350 nm. Two 25‐nanobeam‐cavity arrays are fabricated with a footprint of 215 × 120 µm2 and an average insertion loss of ≈3.2 dB over a broad wavelength range. To the best of the authors’ knowledge, this is the largest‐channel‐count multiplexed micro‐cavity array on a single waveguide, reported to date. As a proof‐of‐principle application, the 2D high‐spatial‐resolution temperature distribution sensing is experimentally demonstrated. This work provides new insight into the design of ultra‐compact FSR‐free filters and will give birth to numerous charming applications that make use of the broad bandwidth capabilities of optics while occupying minimal space.

1411. Operating room air may harbor pathogens: the role of an ultraviolet air filtration unit

Abstract Background Prevention of surgical site infections (SSIs) involves implementation of numerous steps including ultraclean air in the operating room (OR). Despite all efforts, particles in the room air may exist and some of these particles may be live pathogens that can potentially cause subsequent SSI. This prospective study aimed to determine and compare the nature and quantity of microbes in the operating room, as detected from the inlet flow of an ultraviolet filtration unit, and the efficacy of the unit to remove particles and creating clean room air (the outlet flow). Methods This prospective study was conducted at a single institution, where primary total joint arthroplasty and spine surgeries were performed. The OR was fitted with a positive ventilation system. In addition, a filtration unit with a crystalline ultraviolet unit (C-UVC) was placed in the OR. The inflow and outflow air from the unit was sampled using specialized swabs at the beginning and at conclusion of each procedure. Additional surgical-related variables were also recorded at each time of sampling. Swabs were processed for culture and Next-Generation Sequencing. Operating room floor plan The filtration unit with ultraviolet-C light is represented with a red rectangle and doors (source of contamination) are represented by dark gray rectangles. Air flow and air swabs collection. Results The mean length of the surgical procedures sampled was 68 ± 13 minutes. Overall, 19 out of 200 (9.5%) swabs isolated microorganisms. Inflow swabs were positive at a higher rate (16% vs. 3%; p&amp;lt; 0.01), compared to the outcoming air swabs. A wide variety of Gram-positive, Gram-negative, anaerobic bacteria, and fungi (only in the inflow swabs) were isolated. The detection of microorganisms was also higher in surgical procedures with a higher number of door openings (32.5 ± 7.1 vs. 27.9 ± 5.6; p&amp;lt; 0.01). Surgical-related variables collected at air swab sampling. Conclusion Microorganisms are present in the operating room air. A specialized filtration unit with a C-UVC light was effective in filtering these microorganisms in the majority of cases. Disclosures Javad Parvizi, MD, FRCS, 3M: Grant/Research Support|Acumed, LLC: Stocks/Bonds|Aesculap: Grant/Research Support|Alphaeon: Stocks/Bonds|AO Spine: Stocks/Bonds|Becton Dickenson: Advisor/Consultant|Biomet: Grant/Research Support|Cardinal Health: Advisor/Consultant|Cempra: Grant/Research Support|CeramTec: Grant/Research Support|Ceribell: Stocks/Bonds|Coracoid: Stocks/Bonds|Corentec: Advisor/Consultant|Datatrace: Grant/Research Support|DePuy: Grant/Research Support|Elsevier: Grant/Research Support|Elute: Stocks/Bonds|Ethicon: Advisor/Consultant|Hip Innovation Technology: Stocks/Bonds|Illuminus: Stocks/Bonds|Integra: Grant/Research Support|Intellijoint: Stocks/Bonds|Jaypee Publishers: Grant/Research Support|KCI / 3M (Acelity): Advisor/Consultant|Lima: Grant/Research Support|MicroGenDx: Advisor/Consultant|Molecular Surface Technologies: Stocks/Bonds|Myoscience: Grant/Research Support|Nanooxygenic: Stocks/Bonds|National Institutes of Health (NIAMS &amp; NICHD): Grant/Research Support|NDRI: Grant/Research Support|Novartis: Grant/Research Support|OREF: Grant/Research Support|Orthospace: Grant/Research Support|Osteal: Stocks/Bonds|Parvizi Surgical Innovations and Subsidiaries: Stocks/Bonds|Peptilogic: Stocks/Bonds|Peptilogics: Advisor/Consultant|Pfizer: Grant/Research Support|PRN-Veterinary: Grant/Research Support|Rotation Medical: Grant/Research Support|Simplify Medical: Grant/Research Support|SLACK Incorporated: Grant/Research Support|Smith &amp; Nephew: Grant/Research Support|Sonata: Stocks/Bonds|Stelkast: Grant/Research Support|Stryker: Grant/Research Support|Synthes: Grant/Research Support|Tenor: Advisor/Consultant|TissueGene: Grant/Research Support|Tornier: Grant/Research Support|Wolters Kluwer Health - Lippincott Williams &amp; Wilkins: Grant/Research Support|Zimmer Biomet: Advisor/Consultant|Zimmer Biomet: Grant/Research Support

Laboratory investigation of filtration indicators in a gravity filtration unit filled with nano-packing

Today, the lack of drinking water has caused severe crises in many countries. One of the ways to deal with water shortages is to treat wastewater. Petrochemical industries are among the factories that produce significant wastewater. These industries cause a lot of damage to the ecosystem. The use of nanomaterials can play a significant role in the removal of wastewater pollutants. The use of nano-packing in the filtration structure has not been investigated in previous literature. In this research, a gravity filtration unit was used to treat the outlet wastewater from the Fajr petrochemical desalination unit. This unit is filled with titanium dioxide nano-packings. The results of this research show that the turbidity of the effluent discharged from the gravity filtration bed is reduced by about 39 %. This research shows that nano-packing has a significant effect on reducing total dissolved solids and organic carbon. This study shows that the amount of total dissolved solids and organic carbon in treated wastewater is equal to 1 % and 17.1 %, respectively. This research shows that the use of a gravity filtration unit has a significant role in reducing petrochemical effluent pollutants.

Shelf life enhancement technique of Musa acuminata in a controlled environment and optimization of process parameters affecting shelf life using genetic algorithm.

An economical and effective storage solution has been designed in this work for the storage of postharvest fruits and vegetables. Musa acuminata or banana has a shelf life of 5-6 days in open uncontrolled environment. This article reports a storage solution of M. acuminata in a controlled enclosure containing titanium oxide (TiO2 )-coated inner walls and irradiated with ultraviolet ray of band "C," an air filtration unit, 5% by volume potassium permanganate (KMnO4 ) solution in a clay pot, grow lights, and activated charcoal granules. The same fruit was kept in an uncontrolled environment too. The percentages of dark spots on banana (M. acuminata) upon storage in controlled and uncontrolled environments have been estimated using an image-processing algorithm. The prediction of dark spots was conducted using multi-linear and multivariate polynomial regression. Experimentation with optimum process parameters obtained with genetic algorithm resulted in a shelf life extension of 6 days as compared to its storage in an uncontrolled environment. The setup can be used in vegetable and fruit markets for the extension of shelf life of postharvest perishable items in a compact and cost-effective manner. The setup does not use any refrigeration process thereby decreasing energy requirement.

Mapping the cytoskeletal architecture of renal tubules and surrounding peritubular capillaries in the kidney.

The human kidney includes ~1 million nephrons which are long U-shaped tubules with convoluted segments that serve as filtration units. During the passage of the ultrafiltrate through a nephron, electrolytes and nutrients are re-absorbed into peritubular capillaries. The fluid remaining in the distal end of the renal tubules flows through the collecting ducts into the ureter. In this study, we generated high-resolution images of mouse kidney sections using confocal microscopy with only two fluorescently tagged biomarkers, F-actin binding phalloidin and CD34 antibodies as a marker for blood vessels. In tile-scan images of entire sections of mouse kidney (composed of >1000 images), the tubule segments are easily identifiable by their F-actin bundles on cell borders and the outlines of the peritubular capillaries by CD34 immunofluorescence. In the inner stripe of the medulla, the vascular bundles composed of vasa recta (straight vessels) could be easily distinguished from the peritubular capillaries by their full circular shapes. The highly vascular inner medulla and the papilla similarly have straight capillaries. About 95% of kidney volume is composed of renal tubules and blood vessels. Thus, our results show that relatively simple cytoskeletal mapping can be used to visualize the structural organization of the kidney. This method can also be applied to examine pathological changes in the kidney.

Effect of fine fibers on secondary fibers and recycled paper

Abstract Recycled paper has become increasingly used as a raw material in the paper industry. However, hornification limits its application. Herein, the effect of recycling on the mechanical properties and microstructure of khasi pine pulp was systematically studied. The mechanical properties deteriorated and water retention value decreased after recycling. X-ray diffraction and Fourier-transform infrared spectroscopy revealed that cellulose crystallinity increased and partial cocrystallization occurred on cellulose microfibrils. Through the analysis of the morphology of secondary fibers by FQA, the loss of fine fibers caused by each reuse was found. Using the filtration method to prepare the recycled paper reduced the loss of fine fibers and improved the mechanical properties, with the tensile strength of a sample prepared using a sand core filter unit for five cycles (8.37 MPa) being like that of a sample prepared using a paper machine after one cycle. The investigation of the internal structure of the paper showed that the retained fine fibers were bonded between the long fibers, promoting the bonding between the fibers. Fine fibers improve the curling and twisting of fibers to some extent, especially in the first three recycling cycles. The hornification phenomenon of recycled paper was studied from the viewpoint of the fiber components, which is important to promote the development and application prospect of recycled paper.