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Adhering to ASTM C109/C109M-20 standards ensures quality in cement mortar specimens. However, achieving the required sand gradation per ASTM C778-21 can be challenging. This paper presents a faster method for adjusting sand gradation without compromising ASTM quality standards. The proposed method involves analyzing six silica sand samples of different gradations, pre-screening sands, using Excel Solver for optimal mixture ratios, making automated gradation tweaks with precise calculations, and validating the gradation to ensure ASTM compliance. After making the adjustments, compressive strength tests were conducted on mortars with the modified sands, and the results were compared with those of standard-graded sand. Based on statistical analysis, the new method yielded reliable outcomes with compressive strengths similar to standard sands. This innovation offers a more efficient alternative, paving the way for streamlined practices in civil engineering. [ABSTRACT FROM AUTHOR]

The evaluation of saturated hydraulic conductivity (Ks) constitutes an invaluable tool for the management and protection of groundwater resources. This study attempted to estimate Ks in the shallow aquifer of Kabul City, Afghanistan, in response to the occurring groundwater crisis caused by overexploitation and a lack of an appropriate monitoring system on pumping wells, based on datasets from well drilling logs, various analytical methods for pumping test analyses, and laboratory-based methodologies. The selection of Ks estimation methods was influenced by data availability and various established equations, including Theis, developed by Cooper–Jacob, Kruger, Zamarin, Zunker, Sauerbrei, and Chapuis, and pre-determined Ks values dedicated to well log segments exhibited the highest correlation coefficients, ranging between 60% and 75%, with the real conditions of the phreatic aquifer system with respect to the drawdown rate map. The results successfully obtained local-specific quantitative Ks value ranges for gravel, sand, silt, clay, and conglomerate. The obtained results fall within the high range of Ks classification, ranging from 30.0 to 139.8 m per day (m/d) on average across various calculation methods. This study proved that the combination of pumping test results, predetermined values derived from empirical and laboratory approaches, geological description, and classified soil materials and analyses constitutes reliable Ks values through cost-effective and accessible results compared with conducting expensive tests in arid and semi-arid areas. [ABSTRACT FROM AUTHOR]

Natural sand samples collected from bedload or suspension transport can be too small to be sieved. However, related transported mass to sediment size is crucial to calibrate sediment transport models. Image analysis technique can be an easy and cheap alternative. The present study proposes a general law valid for natural sand grains and small gravels that statistically relates elongation to flatness of particles and gives after some assumptions on grain shape and orientation of grains at the sieve mesh passage, the closest distribution of mass to sieving technique from images of grains given by a flatbed scanner. The proposed model is based on the hypothesis of an ellipsoidal grain shape and a preferential grain crossing aligned with the sieve diagonal. Any sand either homogeneous or heterogeneous from various origins (fluvial, marine and quarry) can be analysed directly without any further need for calibration. [ABSTRACT FROM AUTHOR]

The study's objective was to assess the particle-size distribution and formulate an empirical model for the content of the finest dust created during the sanding of unmodified and thermally modified pine wood. The experimental design included unmodified and two options of thermally modified pine (Pinus sylvestris L.) wood samples, four feed speeds (3; 6; 9; 12 m·min−1), and three grit sizes of sanding belts (P60; P80; P100). The wood dust samples underwent sieve analysis to determine the particle-size distribution and laser analysis to determine the content of the finest particles. The sanding of thermally modified wood produced a higher amount of fine dust compared to unmodified wood. The content of fine dust increased with decreasing feed speed, while larger grit sizes resulted in increased production of fine dust. The average mass share of dust < 2.5, < 4, and < 10 µm was significantly lower when sanding the unmodified wood than thermally modified wood. The influence of feed speed, grit size, and material type on dust creation suggests that thermal modification is a factor in increasing the content of the potentially harmful finest particles (respirable fraction). The presented empirical model can help minimize health risks during the sanding of thermally modified pine wood by adjusting the sanding parameters. [ABSTRACT FROM AUTHOR]

This paper reviews a study on processing titanomagnetites using low-temperature treatment and magnetic separation. Using a reduction agent (15 %), chloride additives (15 %), and calcium fluoride (5 %) in low-temperature treatment reduced titanium magnetite iron content. This process extracted iron from titanium precisely and thoroughly. The best low-temperature treatment time and temperature were 60 minutes and 1200 °C. Magnetic separation with 0.2 T magnetic field intensity yielded 75.5 % magnetic fraction. Titanomagnetites treated at low temperatures had 50.9 % magnetic portion iron. Magnetic fraction iron extraction was 97.8 %. The yield of 24.5 % was achieved while the non-magnetic concentrate's titanium dioxide content grew to 65 %.

An atmospheric plasma spray deposition process was adopted for coating regular-shaped, Stellite 6 powder directly on a rolled 3mm size AISI 304 austenitic grade stainless steel substrate without any intermediate bond layers. Coating thickness as measured in a scanning electron microscope was obtained as 74 μm, 128 μm, and 215 μm. An experimental investigation of the functional behavior such as corrosion, microhardness, and erosion of the coated steel at different operating temperatures was undertaken to determine the suitability of its application in the industry. Erosion tests were conducted in an air jet tribo-tester utilizing alumina as an erodent with normal impingement angle at room temperature, 300∘C, and 600∘C. It was difficult to identify a single coating thickness that can be satisfactorily used for superior erosive wear properties with corrosion resistance. So modern management tools such as tri-vector and technology sieve analysis procedures as identification techniques were adopted for the selection of the best coating thickness by complying with the mechanical, erosion, and corrosion resistance properties. Steel coated with 128-μm coating thickness provides the best result for a combination of functional characteristics. [ABSTRACT FROM AUTHOR]

The European corn borer is a major pest of corn that overwinters in corn stubble and stalks. Shredding these residues disrupts the larvae's habitat or directly harms them. A corn header has been engineered with a new type of cutting tool on its horizontal choppers, featuring sharp edges and dulled flails, to shred corn stubble near the soil surface. This study investigated the effect of the dulled flails on the shredding intensity of corn stover. Field trials compared flail knives with standard knives for particle size distribution of corn stover and structural integrity of corn stalk segments. Additionally, a common two-step method, which involved a standard knives-equipped corn header followed by tractor-driven flail mowers, was tested. The flail knives reduced the mean particle size by 3.6 mm compared to the standard knives. Subsequent processing with tractor-driven flail mowers, following the corn header using standard knives, led to a reduction in mean particle size by 11.8 mm. It also further reduced the number of incompletely destroyed stalk segments. However, completely intact internodes were scarce in all methods. Given that flail knives enhance shredding intensity without a second processing step, this concept is concluded to be effective for corn stover shredding. [ABSTRACT FROM AUTHOR]

In the Antibody Mediated Prevention (AMP) trials (HVTN 704/HPTN 085 and HVTN 703/HPTN 081), prevention efficacy (PE) of the monoclonal broadly neutralizing antibody (bnAb) VRC01 (vs. placebo) against HIV-1 acquisition diagnosis varied according to the HIV-1 Envelope (Env) neutralization sensitivity to VRC01, as measured by 80% inhibitory concentration (IC80). Here, we performed a genotypic sieve analysis, a complementary approach to gaining insight into correlates of protection that assesses how PE varies with HIV-1 sequence features. We analyzed HIV-1 Env amino acid (AA) sequences from the earliest available HIV-1 RNA-positive plasma samples from AMP participants diagnosed with HIV-1 and identified Env sequence features that associated with PE. The strongest Env AA sequence correlate in both trials was VRC01 epitope distance that quantifies the divergence of the VRC01 epitope in an acquired HIV-1 isolate from the VRC01 epitope of reference HIV-1 strains that were most sensitive to VRC01-mediated neutralization. In HVTN 704/HPTN 085, the Env sequence-based predicted probability that VRC01 IC80 against the acquired isolate exceeded 1 µg/mL also significantly associated with PE. In HVTN 703/HPTN 081, a physicochemical-weighted Hamming distance across 50 VRC01 binding-associated Env AA positions of the acquired isolate from the most VRC01-sensitive HIV-1 strain significantly associated with PE. These results suggest that incorporating mutation scoring by BLOSUM62 and weighting by the strength of interactions at AA positions in the epitope:VRC01 interface can optimize performance of an Env sequence-based biomarker of VRC01 prevention efficacy. Future work could determine whether these results extend to other bnAbs and bnAb combinations. [ABSTRACT FROM AUTHOR]

Milling wood-based materials on CNC devices causes the creation of chips in small sizes that may escape the chip extraction zone to the surrounding environment and pollute the air. The article studied the effect of the feed rate (vf) and the width of cut (ae), transformed into kinematic average chip thickness, on the amounts of chips in respirable sizes <10.0μm created in the cutting zone from particleboards (PB) and medium-density fibreboards (MDF). The amounts of dust-sized chips are discussed and were determined by the sieving analysis. The sizes of potentially respirable chips were estimated by weighting with the laser diffraction method. The highest amounts of chips from PB were of 0.250-0.500 mm (38-41%w), but in MDF, amounts varied depending on cutting conditions. With (ae) 1 mm were in the size range of 0.125-0.250 mm (35-54%w), for (ae) 2 mm (33-35%w), and (ae) 3 mm (36-40%w) with combinations of (vf) 6-8 m·min-1. With a combination of (vf) 10 and 12 m·min-1 distribution moved to a higher size range. Chips in sizes 10.0-4.0 μm were estimated by <1%, for 4.0-2.5 μm <0.5%, in 2.5-0.1 μm <0.3%, and <0.1 μm by <0.05%. Statistically was proven (p<0.05) only in PB, with adjusted (ae) by 1 mm, increasing the value of (vf) from 6 to 12 m·min-1 and also with (vf) at 6 m·min-1, between values of (ae) 1 and 2 mm (hm of 0.025-0.035 mm), will significantly (p<0.05) lower the percentual amounts of chips in sizes 10.0-4.0 and 4.0-2.5 μm. [ABSTRACT FROM AUTHOR]

Bulgaria has a rich diversity of medicinal plants, with around 770 species, or 19% of all plant species in the country. According to the floristic regional division of the country, the Rhodope Mountains are divided into 3 regions: Western, Central, and Eastern. Dospat municipality falls within the area of the Western floristic region. The present study aimed to carry out the identification and sieve analysis of three plants. This study serves as a basis for subsequent research on the content and distribution of biologically active substances in the selected plants and can propose an extraction model for their further optimal extraction. The plants identified were thyme (Thymus callieri Borbás ex Velen), thistle (Onopordum acanthium L.), and hawthorn (Crataegus monogyna). The cropped plants were examined for the presence of both inorganic and organic impurities. Once impurities were removed, the first quality grade plant material was sorted, dried, and ground. The ground plant material was then subjected to sieve analysis, which involved sorting the material into six classes based on particle size. The density of distribution of the size fractions was determined and analyzed for each of the three crop years studied. The study aimed to investigate the variation in the size distribution of the plant material over three crop years. The results showed the nature of the variation in the size distribution of the plant material over the studied range of 0 - 2,000 µm. The density of distribution of the size fractions varied between the different crop years, indicating that factors such as weather and other environmental conditions may have influenced the size distribution of the plant material. The obtained result of the grinding and fractionation can serve as a basis for additional research, contributing complete and qualitative extraction of biologically active composites from the herbal plant source. [ABSTRACT FROM AUTHOR]

On the floodplain of a sandy, braided river in the Central European Lowland, we studied the sedimentary texture of two crevasse splays, which were: (1) formed due to a levee breach in the 2010 flood, and widely documented by hydrological, bathymetric and LIDAR data, (2) developed under natural conditions when the channel was not embanked by artificial levees (dikes). We compare the sedimentological results with a geomorphological map, a model of the floodplain geomorphology showing different facies of fluvial deposition derived from a meandering river, and deposits in cut banks of the river channel. The statistical parameters of the grain size composition and geomorphic features of the splay, shaped by overbank flow through the broken embankment, are similar to the natural landform. Most of the cut banks (60% of alluvial deposits were mapped there) consist of lithofacies representing proximal floodplain; 30% were distal floodplain (muds), and 10% channel (coarse sand with gravel, pebbles and cobbles). We speculate about the palaeogeography of the Lower Vistula, and the origin of muds and coarse deposits in the banks of the channel. We link these unusual sediments with avulsion, deposition in side arms during ice-jam conditions, and dredging of the channel bottom by suction excavator, which reached the fluvioglacial, suballuvial layer on the bedrock protrusion.

The quality of the castings depends, among other influences, on the quality of the moulding mixture used. The silica sands used are characterized by high thermal expansion compared to other sands. The tendency to dilatation of the moulding mixture can be influenced by the choice of the granulometric composition of the basic sand and the grain size. The aim of this work is to present the influence of grain distribution of foundry silica sand BG 21 from Biala Góra (Poland) and the degree of sorting (unsorted, monofraction, polyfraction) on the degree of thermal dilatation of the sand and thus on the resulting quality of the casting and susceptibility to foundry defects. For the purpose of measuring thermal dilatation, clay wash analysis was performed, sieve analysis of the sand was carried out, and individual sand fractions were carefully sorted. The measurements confirmed a higher thermal expansion in the case of monofractional sand grading, up to 51.8 %. Therefore, a higher risk of foundry stress-strain defects, such as veining, can be assumed.

The article focuses on the recycled materials used in sleeper substructure. In the introduction, it summarizes the requirements for bearing layers of railway substructure and recycling of waste construction materials. The article presents the materials on which laboratory tests have been carried out and discusses in detail the most perspective - recycled concrete. For concrete recyclate, the article describes the results of laboratory tests - sieve analysis, determination of optimum moisture, and determination of bearing capacity using California bearing ratio, Immediate bearing index and Static deformation modulus. [ABSTRACT FROM AUTHOR]

The article focuses on the recycled materials used in sleeper substructure. In the introduction, it summarizes the requirements for bearing layers of railway substructure and recycling of waste construction materials. The article presents the materials on which laboratory tests have been carried out and discusses in detail the most perspective – recycled concrete. For concrete recyclate, the article describes the results of laboratory tests – sieve analysis, determination of optimum moisture, and determination of bearing capacity using California bearing ratio, Immediate bearing index and Static deformation modulus.

The particle size distribution of woodworking residues influences the quality of the biofuels made of these materials. Hence, it is essential to investigate the fractional composition of raw materials for pellet production. Tested materials originated from ten parquet manufacturing facilities located in western Poland. The research material consisted of uncontaminated oak (Quercus spp.) wood particles. The tested material had a moisture content ranging from 8.8% to 11.4% and a density of 210.7 ± 1.79 kg/m3. A sieve analysis method segregated the tested material into four distinct size fractions (<1.0 mm, 1.0-2.5 mm, 2.5-5.0 mm, and >5 mm). The average mass shares in these fractions were 53.72 ±0.51%, 35.14 ±0.27%, 9.59 ±0.36%, and 1.55% ±0.11%, respectively. The particle size distributions of wood particles generated in all the facilities demonstrate remarkable similarity. No substantial differences were observed in terms of tilt angle and calorific value. Factors such as variations in raw material species, geographical origins, density, humidity, and technological processes appear to have minimal influence on the sieve-size distributions of the generated sawdust. All these solid wood processing residues can undergo processing into high-quality solid biofuel production. [ABSTRACT FROM AUTHOR]

The quality of the castings depends, among other influences, on the quality of the moulding mixture used. The silica sands used are characterized by high thermal expansion compared to other sands. The tendency to dilatation of the moulding mixture can be influenced by the choice of the granulometric composition of the basic sand and the grain size. The aim of this work is to present the influence of grain distribution of foundry silica sand BG 21 from Biala Góra (Poland) and the degree of sorting (unsorted, monofraction, polyfraction) on the degree of thermal dilatation of the sand and thus on the resulting quality of the casting and susceptibility to foundry defects. For the purpose of measuring thermal dilatation, clay wash analysis was performed, sieve analysis of the sand was carried out, and individual sand fractions were carefully sorted. The measurements confirmed a higher thermal expansion in the case of monofractional sand grading, up to 51.8 %. Therefore, a higher risk of foundry stress-strain defects, such as veining, can be assumed. [ABSTRACT FROM AUTHOR]

Granular soils are used in different areas of civil engineering due to their easy accessibility and low cost as a material. The sieve analysis method, which has been conducted in rock physics measurements for many years, has been practicing determining the particle size distributions for those materials. In this study, a method based on image analysis technique has been developed as an alternative to traditional sieve analysis method for determining the particle size distribution in granular soils. This technique based on image processing to determine particle distributions via the experimental setup that consist of a camera, tripod, light box and mechanical shaking apparatus. In order to assess the reliability of this technique, each sample was subjected to traditional sieve analysis and the results of both analysis methods were compared. In conclusion, it was observed that the results obtained with the image processing technique had a minimum 95.22% closeness with the sieve analysis experiment data. [ABSTRACT FROM AUTHOR]

The size reduction of dehulled raw gorgon nut kernels was carried out for varied milling time (30, 60 and 90 s) using a batch type laboratory grinder. The effect of milling time was studied in terms of mass fractions (%), average particle size (µm), and fineness modulus. The milled raw gorgon nut flour (RGNF) was sieved into six varied particle size fractions (300–75 µm) using a set of US standard sieves. Differential size fractions were further characterized in terms of physico-chemical; nutritional, color quality, flowability, and functional characteristics. The percent decrease in average flour particle size and fineness modulus was 4.4% and 7.1%, respectively. The protein (7.88–11.18%), amylose (7.63–23.73%), L values (54.92–89.31), b values (4.88–8.63), hue (0.88–1.00), chroma (5.93–8.42), loose bulk density (380.45–669.41 kg/m3), tapped density (400.47–812.86 kg/m3), carr's index (5.00–20.00%), hausner ratio (1.05–1.25), water solubility index (3.08–10.36%) and swelling index (0.51–1.71) increased; whereas, ash (2.58–0.40%); fiber (2.68–1.46%); total phenols (22.65–1.14 mg GAE/g); DPPH radical scavenging activity (56.37–23.24%); a values (3.63–0.61); water absorption capacity (2.30–1.05 g/g); oil absorption capacity (2.35–0.88 g/g) decreased. Statistically, effect of milling time on measured quality characteristics was found significant. Overall, the average flour particle size and fineness modulus decreased with increase of milling time, but it was observed that particle size has pronounced effect on measured quality characteristics of RGNF fractions. While investigating, it was also found that beyond milling time of 60 s, the flour fractions displayed some undesirable changes as evident from slight deterioration of color and nutritional quality of flour fractions. Thus, after comparing all tested samples, a milling time of 60 s using a batch type laboratory grinder is recommended, to obtain superior quality raw gorgon nut flour for food and allied applications. [ABSTRACT FROM AUTHOR]

Rainfall has become a main trigger of slope failure for embankments in most coastal areas. The common slope stability analysis is incapable of accurately forecasting slides where suction pressures play a critical role. This realization is used for elaborate stability analyses, which include mesh and suction to better predict rainfall-induced slides at effective slopes. Jute fibre is one of the reinforced materials which is utilized to improve soil strength. Accordingly, the present study explores to study the effects of slope inclination on soil stability and the collected soil samples using jute fibre in artificial rainfalls. Therefore, this article presented various assessments for soil sample testing. Different tests like sieve analysis, permeability test, direct shear test (DST), liquid limit, plasticity limit, and numerical modelling were conducted in the laboratory. Geo-studio 2021 is the software utilized for numerical and experimental modelling. The findings of the research revealed that the failure is caused by a soil suction loss when the inclination of the slope is higher than the soil friction angle. Subsequently, when the inclination of the slope is lower than the soil's friction angle, the collapse is caused at the slope's toe due to the improvement of the positive water pressure. Furthermore, when the slope angle increases, slopes are becoming increasingly vulnerable to rapid collapse under rainfall. Consequently, the article studies the jute fibre which is combined with soil to improve its soil performance while using two rows, three rows, and four rows of jute. This estimation results that the jute fibre performs better than the without using jute fibre under different rainfall conditions. According to the findings, the random distribution of jute fibres had a favourable influence on both strength measurements and safety aspects. Utilizing the factor of safety and matric suction, the performance of jute fibre is superior to those without using jute fibres. Consequently, the proposed work improves the stabilization of soil, and factor of safety with jute fibre in rainfall conditions. [ABSTRACT FROM AUTHOR]

Heavy rainfall is often responsible for embankment failures. During intense rainfall, the embankment slope inclination is vital for slope stability. Some failures occur in the slope due to heavy rainfall and sudden change in the matric suction. Jute fiber is a reinforcing material that is added to improve soil strength. In this research, in order to explore the effects of slope inclination on soil stability, soil samples were collected and exposed to artificial rainfalls. This study presented various tests performed on the soil samples. Different tests like sieve analysis, permeability test, Direct Shear Test (DST), liquid limit, plasticity limit, and numerical modeling were conducted in the laboratory. The study's findings revealed that the failure is caused by a soil suction loss when the inclination of the slope is higher than the soil friction angle and the collapse is caused by the positive water pressure at the slope's toe when it is lower than the soil's friction angle. Furthermore, when the slope angle increases, the slopes are becoming increasingly vulnerable to rapid collapse. After that, jute fibers were combined with the soil to improve its performance. Samples of 2, 3, and 4 rows of jute fibers were tested. These jute fiber samples performed better than the ones without fibers under different rainfall conditions. The distribution of jute fibers had a favorable influence on both strength measurements and safety aspects. Utilizing the factor of safety and matric suction, the performance of jute fiber samples is superior to those without jute fibers. Consequently, by adding jute fibers the stabilization of the soil is significantly improved along with its factor of safety. [ABSTRACT FROM AUTHOR]

• The powder grain size distribution functions obtained using different measurement techniques were compared. • Measurement methods reported different grain size results and had different accuracies. • The range of grain classes and the nature of the particle size distribution had a major influence on the results. This article concerns comparing the grain size distribution functions of mineral powder samples and analyzes errors obtained by various measurement methods. The research used three standard and currently most frequently used methods: sieve analysis, laser diffraction analysis and vision analysis. The most important research, from the point of view of unification of results, consisted in performing precise analyses of the grain size of mineral powders (fly ash, gneiss, quartz sand and Cu ore) in various grain classes. The measurement techniques used in the research and issues related to measurement analytics were characterized. The distribution functions of the grain size distributions of the tested material samples were obtained by different measurement methods and the measurement errors were compared. Using the coefficient of variation CV calculated for characteristic particle diameters, the accuracy of measurements made using various methods was analyzed. It has been shown that different particle size measurement techniques give significantly different particle size distributions for the same material, with the grain size distribution of the measured samples having a greater impact on the results than the material itself. The lowest values of the coefficients of variation were obtained for wet sieve analysis and the highest for laser diffraction. Reliable data informing about grain size distributions were generated for further model calculations necessary to standardize the results between measurement methods. [ABSTRACT FROM AUTHOR]

In this study, terrace soil investigation was carried out in project E-35 (phase-I) China-Pak Economic Corridor, Lesser Himalayas, North Pakistan. The methodology in current research is based on tests that include sieve analysis, plastic index, proctor, California Bearing Ratio, Los Angeles, sand equivalent and specific gravity. The results of these tests for different layers were compared with AASHTO and NHA specifications. The results show that the embankment, subgrade and subbase layers were composed of silt, sand and gravel, respectively while the aggregate base coarse was composed of sand, aggregate and less amount of fine clay material. The sieve analysis test shows that soil and aggregate base coarse has less clay with high silt, sandy material and index plastic to low plastic, which is appropriate for the construction. The California Bearing Ratio shows that the soil and aggregate base coarse have high load-bearing capacity. The Los Angeles abrasion reveal that the sub base and aggregate base coarse are resistive. The sand equivalent shows that aggregate base coarse has high sand material. The specific gravity illustrates that aggregate base coarse material is denser. The current study shows that terrace soil is suitable for the construction of the road in project E-35 (phase-I) China-Pak Economic Corridor.

• This correlates analysis integrated host immune response & pathogen sequence data. • The nAb correlate of risk depends on dengue sequence in baseline seropositive participants. • Dependency of correlates on sequence-distance stronger in the vaccine (vs placebo) arm. • Infection- vs vaccine-induced nAbs may affect dengue risk differently. • nAb titer approximate surrogate endpoint of dengue disease in baseline-seropositive 9–14-year-olds. In the CYD14 trial of the CYD-TDV dengue vaccine in 2–14 year-olds, neutralizing antibody (nAb) titers to the vaccine-insert dengue strains correlated inversely with symptomatic, virologically-confirmed dengue (VCD). Also, vaccine efficacy against VCD was higher against dengue prM/E amino acid sequences closer to the vaccine inserts. We integrated the nAb and sequence data types by assessing nAb titers as a correlate of sequence-specific VCD separately in the vaccine arm and in the placebo arm. In both vaccine and placebo recipients the correlation of nAb titer with sequence-specific VCD was stronger for dengue nAb contact site sequences closer to the vaccine (p = 0.005 and p = 0.012, respectively). The risk of VCD in vaccine (placebo) recipients was 6.7- (1.80)-fold lower at the 90th vs 10th percentile of nAb for viruses perfectly matched to CYD-TDV, compared to 2.1- (0.78)-fold lower at the 90th vs 10th percentile for viruses with five amino acid mismatches. The evidence for a stronger sequence-distance dependent correlate of risk for the vaccine arm indicates departure from the Prentice criteria for a valid sequence-distance specific surrogate endpoint and suggests that the nAb marker may affect dengue risk differently depending on whether nAbs arise from infection or also by vaccination. However, when restricting to baseline-seropositive 9–14 year-olds, the correlation pattern became more similar between the vaccine and placebo arms, supporting nAb titers as an approximate surrogate endpoint in this population. No sequence-specific nAb titer correlates of VCD were seen in baseline-seronegative participants. Integrated immune response/pathogen sequence data correlates analyses could help increase knowledge of correlates of risk and surrogate endpoints for other vaccines against genetically diverse pathogens. Trial registration: EU Clinical Trials Register 2014-001708-24; registration date 2014-05-26. [ABSTRACT FROM AUTHOR]

SARS‐CoV‐2 continues to evolve and the vaccine efficacy against variants is challenging to estimate. It is now common in phase III vaccine trials to provide vaccine to those randomized to placebo once efficacy has been demonstrated, precluding a direct assessment of placebo controlled vaccine efficacy after placebo vaccination. In this work, we extend methods developed for estimating vaccine efficacy post placebo vaccination to allow variant specific time varying vaccine efficacy, where time is measured since vaccination. The key idea is to infer counterfactual strain specific placebo case counts by using surveillance data that provide the proportions of the different strains. This blending of clinical trial and observational data allows estimation of strain‐specific time varying vaccine efficacy, or sieve effects, including for strains that emerge after placebo vaccination. The key requirements are that the surveillance strain distribution accurately reflects the strain distribution for a placebo group throughout follow‐up after placebo group vaccination, and that at least one strain is present before and after placebo vaccination. For illustration, we develop a Poisson approach for an idealized design under a rare disease assumption and then use a proportional hazards model to address staggered entry, staggered crossover, and smoothly varying strain specific vaccine efficacy. We evaluate these methods by theoretical work and simulations, and demonstrate that useful estimation of the efficacy profile is possible for strains that emerge after vaccination of the placebo group. An important principle is to incorporate sensitivity analyses to guard against misspecification of the strain distribution. [ABSTRACT FROM AUTHOR]

Purpose. To determine the granulometric composition of technogenic raw materials for agglomeration by the adhesive-chemical method. This approach allows for determining the optimal particle size distribution for obtaining the prepared agglomerated fuel, which has the form of cylindrical rods with a diameter of 30 mm and a length of 50–200 mm. Methodology. The granulometric composition of technogenic raw materials was determined using sieve and sedimentation analyses. 38 representative samples of carbon-containing raw materials were subjected to the investigation. Findings. The sieve analysis results of representative samples of coal sludge and culms are presented; their graphical characteristics is given. Sieve analysis of the granulometric composition of samples of carbon-containing raw materials and sedimentation analysis of solid fuel samples with a fraction of fewer than 50 microns is carried out. It has been established that all samples with sizes of more than 5–6 mm should be subjected to further grinding. Originality. For the first time, studies and comparative analysis of granulometric compositions of technogenic raw materials have been realized, which allows for a reasonable approach to obtaining composite fuel from carbon-containing wastes by the adhesive-chemical method, using various compositions of components. Practical value. The results can process technogenic raw materials to get agglomerated fuel of specified parameters by the adhesive-chemical method and other processing areas, including using carbon-containing waste from various productions. [ABSTRACT FROM AUTHOR]

The article indicates the hazard classes and maximum permissible concentrations (MPC) of aerosols in the air of the working area. The results of sieve analysis of dust-like material PPG-30P, as well as the distribution of its grains by size classes and chemical composition with MPCs for soils are presented. Possible directions for the utilization of dust-like material are considered, and a vehicle for its collection is proposed. [ABSTRACT FROM AUTHOR]

The silica contained in biomass is generally recovered from the ashes after combustion. In this study, the main objective was the recovery of silica from wheat straw, without degrading the other biomass components. To achieve this goal, the wheat straw was first pre-treated by an acidic organosolv process to separate it into its three major components: cellulose, lignin, and hemicelluloses. The silica, due to the pre-treatment conditions, was in the cellulose fraction, from which it was extracted, under alkaline conditions. The goal was to recover pure silica with suitable particle size and BET surface area, enabling its use in various industrial applications. The extraction and precipitation steps of silica recovery were studied. After optimization, the silica extraction conditions were set at pH 9 to 10 and 85 °C and the precipitation at pH 5 to 5.5. In these conditions, up to 82% of total silica in straw was extracted with high purity, an average particle size of 4 µm, and a BET surface area of 156 m²/g. In summary, silica can be extracted from lignocellulosic biomass, at high yield and purity, without affecting the biorefinery co-products’ yields and quality. [ABSTRACT FROM AUTHOR]

The protective effects of vaccines may vary depending on individual characteristics, such as age. Traditionally, such effect modification has been examined with subgroup analyses or inclusion of cross‐product terms in regression frameworks. However, in many vaccine settings, effect modification may also depend on the infecting pathogen's characteristics, which are measured postrandomization. Sieve analysis examines whether such effects are present by combining pathogen genetic sequence information with individual‐level data and can generate new hypotheses on the pathways whereby vaccines provide protection. In this article, we develop a causal framework for evaluating effect modification in the context of sieve analysis. Our approach can be used to assess the magnitude of sieve effects and, in particular, whether these effects are modified by individual‐level characteristics. Our method accounts for difficulties occurring in real‐world data analysis, such as competing risks, nonrandomized treatments, and differential dropout. Our approach also integrates modern machine learning techniques. We demonstrate the validity and efficiency of our approach in simulation studies and apply the methodology to a malaria vaccine study. [ABSTRACT FROM AUTHOR]

This article deals with the fractionation of wood dust by sieve after sanding. Dust from untreated beechwood was compared to dust from thermally modified beechwood (at 200 °C for 3 h). The authors hypothesized that the thermal modification changes the particle size distributions of the dust sieve fractions and that all the dust sieve fractions contain the finest particles, which are suspendable in the air and are potentially respirable. To obtain dust for testing, both wood materials were sanded with P120 paper at a belt speed of 14.5 m/s and a pressure of 0.65 N/cm² . A set of sieves with aperture sizes of 25, 80, and 250 µm were used to separate the dust into sieve fractions with grain sizes less than 25 µm, 25 to 80 µm, 80 to 250 µm, and greater than 250 µm. The content of the finest particles in the fractions was measured via a laser particle sizer. Both dusts had similar particle size distributions. In addition, each investigated fraction of both dusts contained the finest particles, i.e., less than 10 µm. It follows that the laser analysis method may be necessary to correctly assess the occupational risk at a sanding. [ABSTRACT FROM AUTHOR]

Abstract Sanding dust is the main source of dust emission during the manufacturing process of medium-density fiberboard (MDF), and particle size and shape characteristics are the fundamental properties influencing its environmental influence and handling behaviors. However, there are few deep and comprehensive researches on the morphology of MDF sanding dust. In this study, the morphological characteristics of MDF sanding dust were explored by sieve and image analyses. It was found that more than 95% of MDF sanding dust was inhalable particles smaller than 100 μm, which poses a considerable potential risk to human health and safety, especially with the presence of other chemical constituents. The particle size span of MDF dust was relatively wide though the particle surface texture was quite uniform. The particle geometric proportion represented by aspect ratio decreased markedly with the reduction of particle size. The larger particles presented typical anisotropic structure, while the smaller ones showed homogeneous appearance, indicating quite complex handling behaviors. In addition, image analysis was found to provide a better insight into the morphological characteristics of MDF sanding dust compared to sieve analysis, and could be a promising dust morphology evaluation technology.

This work’s goal is to investigate the influence of the type and size of fine aggregate on the characteristics of foamed concrete. Foamed concrete was produced, and its fresh and mechanical characteristics were investigated. It was found that the spread diameter decreased when the foam was added to mixes. With regards to sand grading, when the grading of sand decreased, the diameter of the flow decreased also. Strength improved for fineness sand and enabled the production of uniform and pore distribution, which enhanced the foamed concrete's strength. The increase in compressive strength reflects the other properties of concrete, like tensile strength, that also improved.

Coronavirus disease 2019 (COVID-19) vaccine breakthrough infections have been important for all circulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant periods, but the contribution of vaccine-specific SARS-CoV-2 viral diversification to vaccine failure remains unclear. This study analyzed 595 SARS-CoV-2 sequences collected from the Military Health System beneficiaries between December 2020 and April 2022 to investigate the impact of vaccination on viral diversity. By comparing sequences based on the vaccination status of the participant, we found limited evidence indicating that vaccination was associated with increased viral diversity in the SARS-CoV-2 spike, and we show little to no evidence of a substantial sieve effect within major variants; rather, we show that rapid variant replacement constrained intragenotype COVID-19 vaccine strain immune escape. These data suggest that, during past and perhaps future periods of rapid SARS-CoV-2 variant replacement, vaccine-mediated effects were subsumed with other drivers of viral diversity due to the massive scale of infections and vaccinations that occurred in a short time frame. However, our results also highlight some limitations of using sieve analysis methods outside of placebo-controlled clinical trials., Competing Interests: The views expressed are those of the authors and do not reflect the official policy of the Uniformed Services University of the Health Sciences (USUHS), Department of the Army, Department of the Navy, the Department of the Air Force, the Department of Defense or the US Government, and the Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF). The investigators have adhered to the policies for protection of human subjects as prescribed in 45 CFR 46. Drs Berjohn, Fries, Smith, Mody, Huprikar, Lindholm, Jones, Larson, Ewers; Ms Bazan; and Drs Saunders, Maldonado, Simons, Tribble, and Burgess are service members or employees of the US Government. This work was prepared as part of their official duties. Title 17 USC §105 provides that “Copyright protection under this title is not available for any work of the United States Government.” Title 17 USC §101 defines a US Government work as a work prepared by a military service member or employee of the US Government as part of that person’s official duties., (© The Author(s) 2024. Published by Oxford University Press.)

The scale of the HIV-1 epidemic underscores the need for a vaccine. The multitude of circulating HIV-1 strains together with HIV-1's high evolvability hints that HIV-1 could adapt to a future vaccine. Here, we wanted to investigate the effect of vaccination on the evolution of the virus post-breakthrough infection. We analyzed 2,635 HIV-1 env sequences sampled up to a year post-diagnosis from 110 vaccine and placebo participants who became infected in the RV144 vaccine efficacy trial. We showed that the Env signature sites that were previously identified to distinguish vaccine and placebo participants were maintained over time. In addition, fewer sites were under diversifying selection in the vaccine group than in the placebo group. These results indicate that HIV-1 would possibly adapt to a vaccine upon its roll-out. [ABSTRACT FROM AUTHOR]

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The paper deals with the selected characteristics, such as moisture, average bulk density, and fraction size, of tropical marblewood dust (Marmaroxylon racemosum) that influence its ignition risk. Research was focused on sieve analysis, granulometric analysis, measurement of moisture level in the dust, and determination of the minimum ignition temperatures of airborne tropical dust and dust layers. Samples were prepared using a Makita 9556CR 1400W grinder and K36 sandpaper for the purpose of selecting the percentages of the various fractions (<63, 63, 71, 100, 200, 315, 500 μm). The samples were sized on an automatic vibratory sieve machine Retsch AS 200. More than 65% of the particles were determined to be under 100 μm. The focus was on microfractions of tropical wood dust (particles with a diameter of ≤100 µm) and on the impact assessment of particle size (particle size < 100 µm) on the minimum ignition temperatures of airborne tropical dust and dust layers. The minimum ignition temperature of airborne marblewood dust decreased with the particle size to the level of 400 °C (particle size 63 μm). [ABSTRACT FROM AUTHOR]

Wood dust generated during woodworking—particularly from hardwood species during sanding—poses a health and safety hazard to workers in the wood industry. This study aimed to determine the particle-size distribution of selected hardwood species and the content of fine particles in dust created during machine sanding, which pose the highest health and safety hazards in the woodworking industry. Six hardwood species were studied: black alder, European ash, common walnut, pedunculate oak, hornbeam, and European beech. The sieve analysis method was used to determine the particle-size distribution and article mean arithmetic particle diameter, and laser diffraction analysis was used to determine the finest particle content. Two size ranges were assumed: <2.5 μm and <10 μm. Beech dust had the smallest mean particle diameter. Dust from wood species used in the test had similar contents of fine fractions of particles. The average content of particles smaller than 2.5 µm in wood dust from the tested hardwood species did not exceed 1.9%. In terms of occupational exposure to wood dust, machine sanding conditions of hardwoods should be properly adjusted to limit the formation of large amounts of dust. [ABSTRACT FROM AUTHOR]

Complete diets for laying hens are usually offered in meal form. This form initially promotes the laying hens’ natural feed intake behavior and allows them to satisfy their pecking behavior. At the same time, it can also cause difficulties, because it consists of different particles and is not a homogeneous unit. A homogeneous mixture is essential to ensure that each laying hen in the flock can meet its nutritional needs. If feed exhibits a wide particle size distribution, this can promote feed segregation during transport and selective feed intake behavior of laying hens. These two processes sometimes lead to significant differences between the composition of the feed produced and the composition of the feed that is finally ingested by the laying hens. Multi-stage sampling can be used to investigate progressing differences in feed composition. In this study, samples of different complete diets for laying hens (n = 76) were collected from ten organic farms in Germany to examine their particle size distributions (dry sieve analysis). Samples were taken at four different locations (V1 = loading, V2 = silo, V3 = at the beginning of the feed chain, V4 = at the end of the feed chain) in each farm. There was a tendency for V1 and V2 to be characterized by high proportions of particles between 1400 and 3150 µm (V1 = 61.2%, V2 = 43.5%). V3 and V4 consisted mainly of particles of size 500–800 µm and 200–400 µm, respectively. The lowest proportions across all variants were in the range above 3150 µm (V1 = 2.20%, V2 = 1.30%, V3 = 1.00%, V4 = 0.400%) and between 400 and 500 µm (V1 = 2.50%, V2 = 4.50%, V3 = 5.70%, V4 = 6.60%). The mean value comparison of the proportions of sieve mesh sizes from 200 to 1000 µm resulted in: V1 < V2 < V3 < V4; and of sieve mesh sizes between 1400 and 2000 µm in: V1 > V2 > V3 > V4. This observation can be explained by segregation of the feed during transport and a selective feeding behavior of the laying hens. However, trends were discontinuous and varied between the farms. Deviations from the guideline values were found in particular for particle sizes in the range of 1000 to 1400 µm.

Many infectious diseases are well prevented by proper vaccination. However, when a vaccine is not completely efficacious, there is great interest in determining how the vaccine effect differs in subgroups conditional on measured immune responses postvaccination and also according to the type of infecting agent (eg, strain of a virus). The former is often called correlate of protection (CoP) analysis, while the latter has been called sieve analysis. We propose a unified framework for simultaneously assessing CoP and sieve effects of a vaccine in a large Phase III randomized trial. We use flexible parametric models treating times to infection from different agents as competing risks and estimated maximum likelihood to fit the models. The parametric models under competing risks allow for estimation of both cumulative incidence‐based contrasts and instantaneous rates. We outline the assumptions with which we can link the observable data to the causal contrasts of interest, propose hypothesis testing procedures, and evaluate our proposed methods in an extensive simulation study. [ABSTRACT FROM AUTHOR]

Sanding dust is the main source of dust emission during the manufacturing process of medium-density fiberboard (MDF), and particle size and shape characteristics are the fundamental properties influencing its environmental influence and handling behaviors. However, there are few deep and comprehensive researches on the morphology of MDF sanding dust. In this study, the morphological characteristics of MDF sanding dust were explored by sieve and image analyses. It was found that more than 95% of MDF sanding dust was inhalable particles smaller than 100 μm, which poses a considerable potential risk to human health and safety, especially with the presence of other chemical constituents. The particle size span of MDF dust was relatively wide though the particle surface texture was quite uniform. The particle geometric proportion represented by aspect ratio decreased markedly with the reduction of particle size. The larger particles presented typical anisotropic structure, while the smaller ones showed homogeneous appearance, indicating quite complex handling behaviors. In addition, image analysis was found to provide a better insight into the morphological characteristics of MDF sanding dust compared to sieve analysis, and could be a promising dust morphology evaluation technology. [ABSTRACT FROM AUTHOR]

The phenomenon of capillary rise happens in soils, and it has a crucial effect on many engineering applications. Many researchers have concluded several experimental equations to estimate this height. This paper presents a comparative and practical study of the three most important equations used in most researches, which are Lane and Washburn, Fetter, and P-K equations. The estimated heights by these three equations were compared with the experimental tests on sand samples taken from Al-Adalah, Al-Furat, and Al-Jameah districts located in Al-Najaf city in the southwest of Iraq. The percentage change for each equation compared with the experimental work. The results illustrated that the Fetter equation is the closest equation to experimental height and gives moderate values, unlike the Lane and Washburn and P-K equations, to save estimation of the pollutants penetration in unsaturated soils. [ABSTRACT FROM AUTHOR]

To prevent premature dismissal of promising vaccine programs, it is critical to determine if lack of efficacy in the field is due to allele specific-efficacy, rather than to the lack of immunogenicity of the candidate antigen. Here we use samples collected during a field trial of the AMA1-based FMP2.1/AS02 A malaria vaccine, which incorporates the AMA1 variant encoded by the reference Plasmodium falciparum 3D7 strain, to assess the usefulness of epitope-based sieve analysis for the detection of vaccine-induced allele-specific immune responses. The samples used are from volunteers who received the malaria vaccine FMP2.1/AS02 A or a control (rabies vaccine), during a vaccine efficacy field trial, and who later developed malaria. In a previous study, P. falciparum DNA was extracted from all samples, and the ama1 locus amplified and sequenced. Here, a sieve analysis was used to measure T and B-cell escape, and difference in 3D7-like epitopes in the two treatment arms. Overall, no difference was observed in mean amino acid distance to the 3D7 AMA1 variant between sequences from vaccinees and controls in B-cell epitopes. However, we found a significantly greater proportion of 3D7-like T-cell epitopes that map to the AMA1 cluster one loop (c1L) region in the control vs. the vaccinee group (p = 0.02), consistent with allele-specific vaccine efficacy. Interestingly, AMA1 epitopes in infections from vaccinees had higher mean IC50, and consequently lower binding affinity, than epitopes generated from the control group (p = 0.01), suggesting that vaccine-induced selection impacted the immunological profile of the strains that pass through the sieve imposed by the vaccine-induced protection. These findings are consistent with a vaccine-derived sieve effect on the c1L region of AMA1 and suggest that sieve analyses of malaria vaccine trial samples targeted to epitopes identified in silico can help identify protective malaria antigens that may be efficacious if combined in a multivalent vaccine. [ABSTRACT FROM AUTHOR]

• Vitamin D 3 and iron- co -blended granules were produced by a continuous process. • The use of Neusilin US2 improved powder flow properties. • The presence of micronutrients in granules was assessed by analytical techniques. • The granule roughness parameters were significantly affected by the composition. • Vitamin D 3 led to cell apoptosis in in vitro cell culture studies. The aim of this study was to develop vitamin D 3 (VD 3) and iron (Fe) blended granules using Neusilin® US2 as an excipient. A central composite design of experiments was used for the continuous manufacturing process, considering VD 3 and iron as independent variables and the bulk density, flow index, oil holding capacity, and color difference as response variables. The addition of VD 3 had a significant effect on the powder flow properties. The X-ray diffraction and Scanning electron microscopy-energy dispersive X-ray analysis validated the presence of VD 3 and Fe in the granules, whereas the variations in porosity and roughness were demonstrated by tomography and atomic force microscopy, respectively. The in vitro cellular uptake profile confirmed the absorption of VD 3 in the breast cancer cell line MCF-7 with apparent apoptosis. These results could help in scaling up the process from laboratory to pilot scale in twin-screw granulation and boost the intervention of VitD 3 /iron deficiencies. [ABSTRACT FROM AUTHOR]

Wood dust generated during woodworking—particularly from hardwood species during sanding—poses a health and safety hazard to workers in the wood industry. This study aimed to determine the particle-size distribution of selected hardwood species and the content of fine particles in dust created during machine sanding, which pose the highest health and safety hazards in the woodworking industry. Six hardwood species were studied: black alder, European ash, common walnut, pedunculate oak, hornbeam, and European beech. The sieve analysis method was used to determine the particle-size distribution and article mean arithmetic particle diameter, and laser diffraction analysis was used to determine the finest particle content. Two size ranges were assumed:

The paper deals with the selected characteristics, such as moisture, average bulk density, and fraction size, of tropical marblewood dust (Marmaroxylon racemosum) that influence its ignition risk. Research was focused on sieve analysis, granulometric analysis, measurement of moisture level in the dust, and determination of the minimum ignition temperatures of airborne tropical dust and dust layers. Samples were prepared using a Makita 9556CR 1400W grinder and K36 sandpaper for the purpose of selecting the percentages of the various fractions (

In the present research work, a low-ash coal, from Ghouzlou deposit in Iran, with an average ash content of 12% was subjected to some beneficiation experiments such as heavy media separation and flotation. Sieve analysis showed that 62.3% of the coal sample with the size of +2 mm had around 7.3% ash contents. Also, heavy media tests carried out on five size fractions revealed that by setting the separation density at 1.4 g/cm3 for the coarse fraction (+1 mm), a 5% ash product with more than 70% coal recovery was obtainable. Samples with lower ash content (5%) based on the Mayer curves to produce a 5% coal product. Moreover, flotation tests on -1 mm fraction could reduce the ash content from more 13.2% to 10.4%.

The paper presents the results obtained from a subsurface sediment grain size analysis along the upper, gravel-bed, Prahova River, Romania. Samples were taken from 20 locations over a 56 km study reach and were subsequently sieved and weighted in the laboratory. Both d50 and d84 characteristic diameters were plotted against distance and an overall downstream coarsening was identified. Considering the natural and anthropic context of the studied reach, hypotheses to explain this trend were launched. [ABSTRACT FROM AUTHOR]

This study investigated the strength properties of commercially manufactured sandcrete blocks in four cities in Southern Nigeria. 12 sandcrete block firms were visited and ten sandcrete block samples were randomly selected from each of these firms and taken to the laboratory for testing. Two sets of control samples were produced in the laboratory using mix ratios of 1:8 and 1:6. Aggregates used for all the block molding were also collected and their particle size analysed. Compressive strength of blocks from the 12 firms visited ranged from 0.19 to 1.32N/mm² and were far below the minimum specified values by NIS 87:2007. Authors ascribe this poor strength to noncompliance to standard. Compressive strength of the control samples revealed that complying with NIS 87: 2007 mix ratio and neglecting some other specified details is still not likely to produce standard products. [ABSTRACT FROM AUTHOR]

Particle size is the top cited physical property researchers report in The Canadian Journal of Chemical Engineering and among the top properties in all science disciplines. [1] Techniques to measure particle size distribution (PSD) include physical operations like sieving and sedimentation, and spectroscopic techniques like laser diffraction image analysis based on optical and electron microscopy, and elecro‐zone instruments. Here we concentrate on laser diffraction analysis (LDA) and review its basic principles, operations, limitations, uncertainties, and mention how it compares to other techniques. LDA is an instantaneous, user‐friendly, convenient, and non‐destructive method to assess PSD of inorganic powders. It measures the scattering angle and intensity of light after it passes through diluted particle dispersions suspended in either a gas or liquid. The Mie theory is an exact solution to resolve the diffraction intensity of light caused by particles that applies to while the Fraunhoffer approximation applies only to particles greater than 20 μm. The 95 % confidence interval of five measurements of 56 μm and 0.1 μm irregularly shaped polyhedrons was ±2.5 %. Based on a bibliometric analysis of LDA of the top 10 000 cited articles in 2016 and 2017, the major research clusters are: particle measurement, powder behaviour, pharmacy, comminution, and adsorption. Future work will continue to introduce more laser sources, combine multiple technologies, implement mobile light sources (dynamic light scattering), and better define characterize irregularly shaped particles. [ABSTRACT FROM AUTHOR]

Probabilistic reliability analysis of suitability of compacted waste wood ash (WWA) treated lateritic soils for use as liners and covers in waste containment structures was assessed using FORTRAN-based First Order Reliability Method. This is based on the predictive model developed from regression analysis and statistical analyses (descriptive statistics and regression) of the results of geotechnical properties of both natural and WWA modified samples in which WWA, water content (WC), percentage fine, plasticity index (PI), degree of saturation (Sr) and compactive effort are the independent variables and hydraulic conductivity (k) the dependent variable. In sensitivity, reliability indices (β) decreased with variations in the coefficient of variation for all the variables at West African Standard and British Standard Heavy (BSH) compactive efforts, but increased at British Standard light except WWA which has no effect by remaining constant. Also, reliability indices increased with increase in compactive efforts. However, apart from WWA, PI has the most significant influence in sensitivity followed by Sr and then WC. Analysis of variance showed that compactive effort has significant effect on the outcome of the results. Stochastic assessment of the reliability indices shows that none of the variables has the reliability index values between 2.5 and 4.0 which is the safety margin in structural reliability; however, the use of reliability index value of 1 according to NKB Report (Recommendation for loading and safety regulations for structural design. Nordic Committee on Building Regulation 1978) was favourable only at BSH compactive efforts. Therefore, only BSH could be used successfully to actualize reliable minimum hydraulic conductivity of 1 × 10−9 m/s in the field using WWA treated lateritic soil. [ABSTRACT FROM AUTHOR]