Improvement of Strength and Permeability Attributes of Silty Sand Type of Soils using Enzyme Induced Calcite Precipitation

ABSTRACT Enzyme Induced Calcite Precipitation (EICP) is one of the soil stabilization techniques based on microbiological activity. In this technique, urea decomposes with the aid of urease enzymes in the presence of calcium chloride and produces calcite, which acts as a bio-clogging and bio-cementing material. In this study, test tube experiments are performed to assess the optimal amount of calcium chloride, urea, and urease enzymes to be used for engineering applications. The silty sand type of soil is treated with different proportions namely; P1 (0.1g urease enzymes, 0.375g urea, 0.9g CaCl2), P2 (0.2g urease enzymes, 0.75g urea, 1.8g CaCl2), and P3 (0.4g urease enzymes, 1.5g urea, 3.6g CaCl2), to analyze their effect on strength and permeability attributes of soils after 14 days of curing time. It was observed that an increase in EICP content causes a substantial increase in shear strength particularly cohesion due to the bio-clogging phenomenon induced in soil particles by EICP which eventually leads to a decrease in permeability and inhibits the activity of urease. Overall, P3 yields higher cohesion (48 kPa) than P1(40 kPa), P2 (43kPa), and untreated soil samples (31 kPa). Furthermore, P3 causes a significant decrease in permeability as compared to P2, P1, and untreated soil samples tested after 14 days of the curing period. The findings of the study suggest the successful implementation of EICP for soil stabilization. Key Words: Enzyme Induced Calcite Precipitation (EICP); permeability; shear strength; bio-clogging; bio-cementation

Development of a cost-based design model for spread footings in cohesive soils

The use of cost-effective construction design approaches is an emerging concept in the field of sustainable environments. The design of the foundation for the construction of any infrastructure-related building entails three basic requirements, i.e., serviceability limit state (SLS), ultimate limit state (ULS), and economics. Engineering economy coupled with safety are the two main essentials for a successful construction project. The conventional design approaches are based on hit and trial methods to approach cost-effective design. Additionally, safety requirements are prioritized over the economic aspect of foundation design and do not consider safety requirements and cost simultaneously. This study presents a design approach that considers foundation construction costs while satisfying all the technical requirements of a shallow foundation design. This approach is called an optimization process in which the cost-based isolated foundation design charts were developed based on the field SPT N data. The design charts are the first of their kind for the robust design of foundations and can be used to compare the economic impact of different bearing capacity models. Furthermore, the design framework considers the quantitative impact of the different applied factors of safety values in terms of cost. The results show that Vesic’s equation yields higher values of bearing capacities than Terzaghi and Meyerhof. On the other hand, Vesic’s theory offers a 37.5% reduction in cost as compared to the conventional design approach of the foundation for isolated footing

The Socioeconomic Impacts of Urban Parks and Green Spaces

The Socioeconomic Impacts of Urban Parks and Green Space

Catastrophic Health Expenditures and Its Socio-economic Consequences: A Case Study of Tehsil Utman Khel Tribal District, Bajaur

Health expenditures become catastrophic when household’s out of pocket spending on availing health care facilities exceeds a specific proportion of its monthly income leading to impoverishment effects. This study analysed health catastrophic expenditures and its economic consequences on the insurgency affected area of Tehsil Utman khel, district Bajaur of erstwhile FATA. Semi-structured questionnaire was used to collect data from 270 households through random sampling technique.  The study applied binary logistic regression model to assess the relationship between health catastrophe and various socio-economic variables. The study revealed that 61% of the households had to face health catastrophic expenditures in last three months. 70% of the respondents reported that health expenditures had affected their daily consumption pattern, whereas 92% of the households had lost their working days due to their own or relative’s health issues. 74% of the household had managed health costs by selling assets and borrowing. Results of the logistic regression indicated that probability of catastrophic health expenditures decreases by 0.007 with one unit increase in income, whereas the probability of catastrophic health expenditures increase by 0.545, 0.00019 and 0.313 with the increase of household size, health care cost and chronic illnesses respectively.  . The study recommends Health financing interventions in the form of insurance or other safety nets to save the poor households from the trap of poverty.   Key words: Health catastrophic expenditures, consumption pattern, working days.                       &nbsp

Knowledge, attitudes and practices of physicians and dentists on medication-related osteonecrosis of the jaw: A cross-sectional survey

Background Bisphosphonate medication can cause osteonecrosis of the jaw, which is an uncommon but serious complication. This survey explores the knowledge, attitudes and practices of dentists and physicians regarding medication-related osteonecrosis of the jaw (MRONJ).Methods A cross-sectional study was conducted among physicians and dentists of Pakistan\u27s secondary and tertiary care hospitals between March and June 2021. Data were collected through a web-based questionnaire distributed among the eligible clinicians involved in prescribing bisphosphonates to patients or management of osteonecrosis. SPSS Statistics 23.0 was used for the data analysis. The frequencies and proportions of the descriptive variables were reported.Results A response rate of 29% was achieved. Only six dentists (n = 6/61; 9.8%) were aware that mammalian target of rapamycin inhibitors could lead to osteonecrosis. Only one-third (n = 9/26; 34.6%) of physicians informed their patients about the possible side effects of bisphosphonates. The most commonly identified risk factor among them was the duration of the drug (n = 77/87; 88.5%) and the least identified was gender (n = 34/87; 39.0%).Conclusions Our study revealed insufficient knowledge among the respondents about the recently updated established guidelines available on MRONJ. The majority of physicians don\u27t refer patients to dentists before prescribing bisphosphonates and other associated medication

Performance Analysis of MPLS and Traditional IP in Node Scalable Networks

Multiprotocol label switching is the latest and developing technology in the world of the internet. It speeds up the network by using the technique of label instead of an IP address. It provides the reliable transmission of data with high speed and low delay. For efficient use of network utilization MPLS has a key feature of QoS. Due to the effective utilization of network resources, minimum delay and predictable performance MPLS technology make it more appropriate for implementing multimedia type applications. In this research, the performance of MPLS technology is compared with the traditional IP network for multimedia traffic in node scalable networks. For simulating and comparing the performance of both technologies OPNET modular 14.5 is used. This comparison is done on the basis of network performance parameters such as packet loss/ traffic drop, end-to-end delay, and throughput. Finally, the results have been evaluated which show that MPLS technology provides better performance as compared to IP in node scalable environment

Correlation, Regression Analysis of Seed Oil Contents in Relation to Morphological Characters in Cotton

Cotton is the backbone of Pakistan’s economy. More than half of the export of Pakistan depends on cotton and cotton-based products. Morphological quantitative traits are important for estimation of cotton yield. In this regard, a study was conducted to evaluate the morphological responses on cotton crop at experimental farm of MNS-University of Agricultural Multan during the year 2019-2020. Four cotton varieties with different time windows (early, normal and late) were sown in a randomized complete block design (RCBD) in a split plot arrangement. Correlation and regression studies of cultivars of Gossypium and Malvaceae were analyzed for quantitative characters. Result revealed that significantly positive correlation of boll weight (r=0.211), seed volume (r=0.138), seed oil content (r=0.020) and negatively correlation with seed index (r= -0.005) was displayed by all traits with seed cotton yield, which showed that seed cotton yield was greatly influenced by all characters. Regression coefficients showed that a unit increase in seed index (b=71.375), seed volume (b=120.326), seed oil content (b=4.954) resulted into a proportional increased in seed cotton yield. In future, this study will helpful in selection program for improvement of cotton varieties towards the yield

Arsenate and arsenite adsorption in relation with chemical properties of alluvial and loess soils

Arsenic is one of the most toxic elements in the soil environment. Understanding of the arsenic adsorption chemistry is essential for evolving the extent of soil and groundwater contaminations. This research was conducted to determine the variation in adsorption behaviour of arsenite and arsenate with depth in different lithology soils. We sampled two parent materials at genetic horizons, and within a parent material, we selected two soils. Besides basic soil characterizations, a laboratory batch experiments were carried out to study the adsorption of arsenate and arsenite. Freundlich adsorption approaches were employed to investigate the adsorption of arsenate and arsenite in the soils. Freundlich isotherms fit arsenate and arsenite sorption data well with r2 values of 0.88–0.98 in most soils. Arsenate and arsenite adsorption varied with the soil properties, especially in clay composition and in the oxides of iron and aluminum. Arsenic adsorption parameters also varied with depth in parent materials, and loess derived soils had greater adsorption capacity as compared to alluvial soils in most of the adsorption parameters. This research concludes that the loess soils had higher arsenic adsorption capacity than the alluvial soils

An updated systematic review on toothbrush contamination: An overlooked oral health concern among general population

Objectives: The present systematic review was conducted to give an overview of toothbrush contamination among the general population and the factors affecting toothbrush contamination with an evidence-based approach. Data/sources: Medline (Pub Med), CINAHL Plus, Cochrane Library and Dentistry and Oral Health Sciences Source were searched for the results after applying the search strategy from January 2012 to May 2022, following inclusion and exclusion criteria. The data were collected using a self-made data collection form on study characteristics, population attributes and the main features, including the study\u27s outcomes. The methodological quality of the included studies was independently evaluated based on the Joanna Briggs Institute\u27s (JBI) critical appraisal checklist for cross-sectional studies and the Risk of Biasness Tool-1 (Rob-1) for randomized controlled trials (RCTs). A descriptive analysis of the included studies was done using SWiM guidelines. The impact of charcoal and non-charcoal brushes on toothbrush disinfection was quantitatively analysed using a forest plot. Study selection: Of the 687 studies screened by title and abstract, 27 articles were selected for full-text evaluation using the EndNote reference program (Ver. X9.2). From these, 15 qualified and were included in the systematic review. Among the selected studies, eight were RCTs, six were cross-sectional studies, and the remaining one was an in vitro experimental study. Conclusions: The toothbrush becomes contaminated even after its first usage, and the contamination level rises with continued use. There are a number of factors that lead to the contamination of brushes, such as increased humidity brought on by a plastic cover or a toilet setting. Charcoal brushes show significant efficacy as compared to regular bristles in reducing toothbrush contamination; however, more RCTs are needed to further assess its efficacy. Nevertheless, rinsing with chlorhexidine mouthwash after daily brushing shows favourable result

Development of a Cost-Based Design Model for Spread Footings in Cohesive Soils

The use of cost-effective construction design approaches is an emerging concept in the field of sustainable environments. The design of the foundation for the construction of any infrastructure-related building entails three basic requirements, i.e., serviceability limit state (SLS), ultimate limit state (ULS), and economics. Engineering economy coupled with safety are the two main essentials for a successful construction project. The conventional design approaches are based on hit and trial methods to approach cost-effective design. Additionally, safety requirements are prioritized over the economic aspect of foundation design and do not consider safety requirements and cost simultaneously. This study presents a design approach that considers foundation construction costs while satisfying all the technical requirements of a shallow foundation design. This approach is called an optimization process in which the cost-based isolated foundation design charts were developed based on the field SPT N data. The design charts are the first of their kind for the robust design of foundations and can be used to compare the economic impact of different bearing capacity models. Furthermore, the design framework considers the quantitative impact of the different applied factors of safety values in terms of cost. The results show that Vesic’s equation yields higher values of bearing capacities than Terzaghi and Meyerhof. On the other hand, Vesic’s theory offers a 37.5% reduction in cost as compared to the conventional design approach of the foundation for isolated footing