Impact of the surface characteristics of rainwater tank material on biofilm development

In order to determine the impact of rainwater construction material on the development of a biofilm, three materials were tested: concrete, clay, and PVC. The biofilm attachment was initially more effective on clay coupons, but, after a period of three days, concrete coupons produced a greater quantity of biofilm than clay and PVC, in that order. The heterotrophic plate count in the rainwater indicated that this quantity tended to first increase following a rainfall, and then decrease. The new materials seemed to attach themselves to the existing biofilm on the wall and/or sediment in the form of small particles. The presence of fecal coliforms in the biofilm coupons was noted after major rainfall events, and this was correlated with the increase in fecal coliforms in the water. This study concluded that the most favorable support for biofilm development is concrete, clay, and PVC, in that order.

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The Impact of Post-Manufacture Treatments on the Surface Characteristics Important for Finishing of OSB and Particleboard

Forests ◽

10.3390/f12080975 ◽

2021 ◽

Vol 12 (8) ◽

pp. 975

Author(s):

Antonio Copak ◽

Vlatka Jirouš-Rajković ◽

Nikola Španić ◽

Josip Miklečić

Keyword(s):

Water Vapour ◽

Oriented Strand Board ◽

Construction Material ◽

Surface Characteristics ◽

Surface Treatments ◽

Factors Affecting ◽

Treatment Conditions ◽

Water Vapour Absorption ◽

The Impact

Oriented strand board (OSB) is a commonly used structural wood-based panel for walls and roof siding, but recently the industry has become interested in OSB as a substrate for indoor and outdoor furniture. Particleboard is mainly used in furniture productions and has become popular as a construction material due to its numerous usage possibilities and inexpensive cost. Moisture is one of the most important factors affecting wood-based panel performance and the post-treatment conditions affected their affinity to water. When OSB and particleboard are used as substrates for coatings, their surface characteristics play an important role in determining the quality of the final product. Furthermore, roughness can significantly affect the interfacial phenomena such as adsorption, wetting, and adhesion which may have an impact on the coating performance. In this research particleboard and OSB panels were sanded, re-pressed and IR heated and the influence of surface treatments on hardness, roughness, wetting, water, and water vapour absorption was studied. Results showed that sanding improved the wetting of particleboard and OSB with water. Moreover, studied surface treatments increased water absorption and water penetration depth of OSB panels, and re-pressing had a positive effect on reducing the water vapour absorption of particleboard and OSB panels.

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Appraisal of Heavy Metal Presence and Water Quality having Microbial Load and Associated Human Health Risk: A study on tube-well water in Nalitabari township of Sherpur district, Bangladesh

Grassroots Journal of Natural Resources ◽

10.33002/nr2581.6853.040204 ◽

2021 ◽

Vol 4 (2) ◽

pp. 48-64

Author(s):

Md. Rayhan Ali ◽

Md. Omar Faruque ◽

Md. Tarikul Islam ◽

Md. Tarek Molla ◽

Md. Shakir Ahammed ◽

...

Keyword(s):

Human Health ◽

Skin Diseases ◽

Human Health Risk ◽

Fecal Coliforms ◽

Plate Count ◽

Well Water ◽

Heterotrophic Plate Count ◽

Alternative Source ◽

Physiochemical Parameters ◽

Tube Well

This article is based on a study aimed to determine physiochemical parameters, fecal coliform, total coliforms, heterotrophic plate count, arsenic, iron and lead of water to evaluate their effects on human health. Analysis was carried out on tube-well water collected from Nalitabari township of Sherpur District in Bangladesh. The dissolved oxygen (DO), total dissolved solids (TDS), salinity and electrical conductivity were in the ranges of 4.30 to 7.30 ppm, 350 to 792 mg/l, 0.2 to 0.5%, and 715 to 1,970 μS/cm. The pH values were slightly lesser or more than permissible value. Due to the vicinity to the latrines, 17 tube-wells’ water was contaminated by fecal coliforms. The highest heterotrophic plate count was 7.5×103 cfu/ml in ward-8 of the town. Eschericia coli and Vibrio cholerae were identified in ratio of 30.56% and 18.06%, respectively, in the tube-well water, resulting into diarrhea among children. About 6.94% of tube-well water was contaminated with arsenic. 3.25% and 4.5% respondents were suffering from skin diseases and headache, respectively. So, an alternative source of drinking water should be arranged for a better public health of present and next generations.

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Impact of Raw Materials and Processing Techniques on The Microbiological Quality of Egyptian Domiati Cheese

International Journal of Veterinary Science ◽

10.37422/ijvs/20.060 ◽

2020 ◽

Keyword(s):

Raw Materials ◽

Microbiological Quality ◽

Raw Milk ◽

Plate Count ◽

E Coli ◽

Fresh Cheese ◽

Processing Techniques ◽

The Impact ◽

Total Yeast

Domiati cheese is the most popular brand of cheese ripened in brine in the Middle East in terms of consumed quantities. This study was performed to investigate the impact of the microbiological quality of the used raw materials, the applied traditional processing techniques and ripening period on the quality and safety of the produced cheese. Three hundred random composite samples were collected from three factories at Fayoum Governorate, Egypt. Collected samples represent twenty-five each of: raw milk, table salt, calf rennet, microbial rennet, water, environmental air, whey, fresh cheese, ripened cheese & swabs from: worker hands; cheese molds and utensils; tanks. All samples were examined microbiologically for Standard Plate Count (SPC), coliforms count, Staphylococcus aureus (S. aureus) count, total yeast & mould count, presence of E. coli, Salmonellae and Listeria monocytogenes (L. monocytogenes). The mean value of SPC, coliforms, S. aureus and total yeast & mould counts ranged from (79×102 CFU/m3 for air to 13×108 CFU/g for fresh cheese), (7×102 MPN/ cm2 for tank swabs to 80×106 MPN/ml for raw milk), (9×102 CFU/g for salt to 69×106 CFU/g for fresh cheese) and (2×102 CFU/cm2 for hand swabs to 60×104 CFU/g for fresh cheese), respectively. Whereas, E. coli, Salmonella and L. monocytogenes failed to be detected in all examined samples. There were significant differences in all determined microbiological parameters (p ≤0.05) between fresh and ripened cheese which may be attributed to different adverse conditions such as water activity, pH, salt content and temperature carried out to improve the quality of the product.

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Soil Moisture Dynamics in Response to Precipitation and Thinning in a Semi-Dry Forest in Northern Mexico

Water ◽

10.3390/w13010105 ◽

2021 ◽

Vol 13 (1) ◽

pp. 105

Author(s):

Argelia E. Rascón-Ramos ◽

Martín Martínez-Salvador ◽

Gabriel Sosa-Pérez ◽

Federico Villarreal-Guerrero ◽

Alfredo Pinedo-Alvarez ◽

...

Keyword(s):

Soil Moisture ◽

Forest Management ◽

Water Availability ◽

Dry Forest ◽

Rainfall Events ◽

Rainfall Characteristics ◽

Northern Mexico ◽

The Difference ◽

The Impact ◽

Moisture Dynamics

Understanding soil moisture behavior in semi-dry forests is essential for evaluating the impact of forest management on water availability. The objective of the study was to analyze soil moisture based in storm observations in three micro-catchments (0.19, 0.20, and 0.27 ha) with similar tree densities, and subject to different thinning intensities in a semi-dry forest in Chihuahua, Mexico. Vegetation, soil characteristics, precipitation, and volumetric water content were measured before thinning (2018), and after 0%, 40%, and 80% thinning for each micro-catchment (2019). Soil moisture was low and relatively similar among the three micro-catchments in 2018 (mean = 8.5%), and only large rainfall events (>30 mm) increased soil moisture significantly (29–52%). After thinning, soil moisture was higher and significantly different among the micro-catchments only during small rainfall events (<10 mm), while a difference was not noted during large events. The difference before–after during small rainfall events was not significant for the control (0% thinning); whereas 40% and 80% thinning increased soil moisture significantly by 40% and 53%, respectively. Knowledge of the response of soil moisture as a result of thinning and rainfall characteristics has important implications, especially for evaluating the impact of forest management on water availability.

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Review of the relationship between aggregates geology and Los Angeles and micro-Deval tests

Bulletin of Engineering Geology and the Environment ◽

10.1007/s10064-020-02097-y ◽

2021 ◽

Vol 80 (3) ◽

pp. 1963-1980

Author(s):

Solomon Adomako ◽

Christian John Engelsen ◽

Rein Terje Thorstensen ◽

Diego Maria Barbieri

Keyword(s):

Los Angeles ◽

Crystal Size ◽

Grain Shape ◽

Mechanical Performance ◽

Pore Space ◽

Construction Material ◽

Engineering Properties ◽

Coarse Grained ◽

The Impact ◽

The Relationship

AbstractRock aggregates constitute the enormous volume of inert construction material used around the globe. The petrologic description as igneous, sedimentary, and metamorphic types establishes the intrinsic formation pattern of the parent rock. The engineering properties of these rocks vary due to the differences in the transformation process (e.g. hydrothermal deposits) and weathering effect. The two most common mechanical tests used to investigate the performance of aggregates are the Los Angeles (LA) and micro-Deval (MD) tests. This study reviewed the geological parameters (including mineralogy, grain and crystal size, grain shape, and porosity) and the relationship to Los Angeles and micro-Deval tests. It was found that high content of primary minerals in rocks (e.g. quartz and feldspar) is a significant parameter for performance evaluation. Traces of secondary and accessory minerals also affect the performance of rocks, although in many cases it is based on the percentage. Furthermore, some studies showed that the effect of mineralogic composition on mechanical strength is not sufficient to draw final conclusions of mechanical performance; therefore, the impact of other textural characteristics should be considered. The disposition of grain size and crystal size (e.g. as result of lithification) showed that rocks composed of fine-grain textural composition of ≤ 1 mm enhanced fragmentation and wear resistance than medium and coarse grained (≥ 1 mm). The effect of grain shape was based on convex and concave shapes and flat and elongated apexes of tested samples. The equidimensional form descriptor of rocks somehow improved resistance to impact from LA than highly flat and elongated particles. Lastly, the distribution of pore space investigated by means of the saturation method mostly showed moderate (R = 0.50) to strong (R = 0.90) and positive correlations to LA and MD tests.

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Assessment of Rainfall-Induced Landslide Distribution Based on Land Disturbance in Southern Taiwan

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi10040209 ◽

2021 ◽

Vol 10 (4) ◽

pp. 209

Author(s):

Chih-Ming Tseng ◽

Yie-Ruey Chen ◽

Chwen-Ming Chang ◽

Yung-Sheng Chue ◽

Shun-Chieh Hsieh

Keyword(s):

Satellite Image ◽

Extreme Rainfall ◽

Land Area ◽

Rainfall Events ◽

Land Disturbance ◽

Bare Land ◽

Southern Taiwan ◽

The Impact ◽

Landslide Distribution ◽

The Relationship

This study explores the impact of rainfall on the followed-up landslides after a severe typhoon and the relationship between various rainfall events and the occurrence, scale, and regional characteristics of the landslides, including second landslides. Moreover, the influence of land disturbance was evaluated. The genetic adaptive neural network was used in combination with the texture analysis of the geographic information system for satellite image classification and interpretation to analyze land-use change and retrieve disaster records and surface information after five rainfall events from Typhoon Morakot (2009) to Typhoon Nanmadol (2011). The results revealed that except for extreme Morakot rains, the greater the degree of slope disturbance after rain, the larger the exposed slope. Extreme rainfall similar to Morakot strikes may have a greater impact on the bare land area than on slope disturbance. Moreover, the relationship between the bare land area and the index of land disturbance condition (ILDC) is positive, and the ratio of the bare land area to the quantity of bare land after each rainfall increases with the ILDC. With higher effective accumulative rainfall on the slope in the study area or greater slope disturbance, the landslide area at the second landslide point tended to increase.

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Effect of different heterotrophic plate count methods on the estimation of the composition of the culturable microbial community

PeerJ ◽

10.7717/peerj.862 ◽

2015 ◽

Vol 3 ◽

pp. e862 ◽

Cited By ~ 12

Author(s):

Eva Theres Gensberger ◽

Eva-Maria Gössl ◽

Livio Antonielli ◽

Angela Sessitsch ◽

Tanja Kostić

Keyword(s):

Microbial Community ◽

Plate Count ◽

Heterotrophic Plate Count

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Prediction of factors affecting activation of soil erosion by mathematical modeling at pedon scale under laboratory conditions

Scientific Reports ◽

10.1038/s41598-020-76926-1 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Saeed Shojaei ◽

Zahra Kalantari ◽

Jesús Rodrigo-Comino

Keyword(s):

Soil Loss ◽

Rainfall Intensity ◽

Quadratic Function ◽

Interactive Effects ◽

Soil Protection ◽

Single Factor ◽

Rainfall Events ◽

Rainfall Duration ◽

The Impact ◽

Runoff Production

AbstractSoil degradation due to erosion is a significant worldwide problem at different spatial (from pedon to watershed) and temporal scales. All stages and factors in the erosion process must be detected and evaluated to reduce this environmental issue and protect existing fertile soils and natural ecosystems. Laboratory studies using rainfall simulators allow single factors and interactive effects to be investigated under controlled conditions during extreme rainfall events. In this study, three main factors (rainfall intensity, inclination, and rainfall duration) were assessed to obtain empirical data for modeling water erosion during single rainfall events. Each factor was divided into three levels (− 1, 0, + 1), which were applied in different combinations using a rainfall simulator on beds (6 × 1 m) filled with soil from a study plot located in the arid Sistan region, Iran. The rainfall duration levels tested were 3, 5, and 7 min, the rainfall intensity levels were 30, 60, and 90 mm/h, and the inclination levels were 5, 15, and 25%. The results showed that the highest rainfall intensity tested (90 mm/h) for the longest duration (7 min) caused the highest runoff (62 mm3/s) and soil loss (1580 g/m2/h). Based on the empirical results, a quadratic function was the best mathematical model (R2 = 0.90) for predicting runoff (Q) and soil loss. Single-factor analysis revealed that rainfall intensity was more influential for runoff production than changes in time and inclination, while rainfall duration was the most influential single factor for soil loss. Modeling and three-dimensional depictions of the data revealed that sediment production was high and runoff production lower at the beginning of the experiment, but this trend was reversed over time as the soil became saturated. These results indicate that avoiding the initial stage of erosion is critical, so all soil protection measures should be taken to reduce the impact at this stage. The final stages of erosion appeared too complicated to be modeled, because different factors showed differing effects on erosion.

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Experimental manipulations of the biomass of introduced carp (Cyprinus carpio) in billabongs. II. Impacts on benthic properties and processes1

Marine and Freshwater Research ◽

10.1071/mf97032 ◽

1997 ◽

Vol 48 (5) ◽

pp. 445 ◽

Cited By ~ 30

Author(s):

A. I. Robertson ◽

M. R. Healey ◽

A. J. King

Keyword(s):

Algal Biomass ◽

Solid Phase ◽

Negative Impact ◽

Oxygen Demand ◽

Sediment Oxygen Demand ◽

Sediment Surface ◽

Nutrient Concentrations ◽

Nutrient Ratios ◽

Biofilm Development ◽

The Impact

Two billabongs on the floodplain of the Murrumbidgee River, Australia, were partitioned in half with impermeable plastic barriers and the biomass of carp was manipulated to establish high- and low-carp biomass treatments in each billabong. Measurements of benthic variables (rates of particle settlement, biofilm development, sediment respiration, macrophyte detritus decomposition, sediment solid-phase nutrient concentrations and benthic algal biomass) were performed over four months from summer to winter 1995. Rates of particle settlement were greater in the high-carp treatment of each billabong throughout the experiment. High carp biomass had a negative impact on the autotrophic component of the biofilm developing on wood blocks placed at different heights above the sediment surface but the mechanism responsible differed between billabongs. Sediment oxygen demand became greater in the presence of a higher biomass of carp during the experiment but time courses differed between billabongs. Manipulations of carp biomass did not influence algal biomass on the sediment surface, the rate of decomposition of macrophyte detritus or sediment solid-phase nutrients or nutrient ratios. The impact of carp on benthic and surficial processes was significant but the mechanisms of change differed between billabongs.

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Possible Causes in Breaking of Dental Implants Research

Materials Science Forum ◽

10.4028/www.scientific.net/msf.907.104 ◽

2017 ◽

Vol 907 ◽

pp. 104-118

Author(s):

Maria Stoicănescu ◽

Eliza Buzamet ◽

Dragos Vladimir Budei ◽

Valentin Craciun ◽

Roxana Budei ◽

...

Keyword(s):

Dental Implants ◽

Dental Implant ◽

Scientific Literature ◽

Surface Characteristics ◽

Raw Material ◽

New Materials ◽

Materials Used ◽

Type Of Failure ◽

First Time ◽

Consequent Increase

Dental implants are becoming increasingly used in current dental practice. This increased demand has motivated manufacturers to develop varieties of product through design, but also looking for new materials used to improve surface characteristics in order to obtain a better osseointegration. But the increase in the use of implants goes to a consequent increase in the number of failures. These failures are caused either by treatment complications (peri-implantitis), by fatigue breakage under mechanical over-stress, by defective raw material, or due to errors during the insertion procedures. Although they are rare, these complications are serious in dentistry. Before to market a dental implant to clinical practitioners, the product is validated among other determinations in number of biocompatibility research. Raw material issues, details about its structure and properties are less published by the scientific literature, but all this are subject of a carefully analysis of the producers. Breaking of dental implants during surgical procedures, during the prosthetic procedures or during use (chewing, bruxism, accidents, etc.), is the second most common cause of loss of an implant after consecutive peri-implantitis rejection. Although the frequency of this type of failure for a dental implant is much smaller than those caused by the peri-implantitis, a detailed study of broken implants can explain possible causes. The use of scanning electron microscopy (SEM) in the study of the cleave areas explain the production mechanism of cleavages, starting from micro-fissures in the alloy used for the production of dental implants. These micro-fissures in weak areas of the implant (anti-rotational corners of the polygons, etc.) could generate a serious risk of cleavage first time when a higher force is applied.

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