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The Thailand National Institute of Health (NIH) established an external quality assessment (EQA) scheme on HIV serology testing since 1994 for many public health laboratories. For the past six years, the NIH has evaluated the activities of 226 laboratories.

Approximately 40,000 tests using 16 trial samples of external quality assessment panel performed at 226 laboratories during 2000‐2006. The methods performed were classified into five assays; machine‐based enzyme immunoassay (MBA), microplate‐based enzyme immunoassay (EIA), simple/rapid test and antigen assay only performed at blood screening laboratory centers. A few laboratories performed confirmation method by western blot (WB). Most participating laboratories performed at least two methods.

The evaluation showed that, during the six‐year period, the program had an increasing response rate among all groups of laboratories: government hospital laboratories, private hospital and clinic laboratories and blood screening laboratory centers. Moreover, there were no significantly different errors found between these groups. The highest median percent of overall errors found was in antigen assay. Very minimal errors appeared on other methods.

National HIV EQA program has played an important role in improving the quality of participating laboratory performance. The participating laboratories gained a better understanding and were able to use good quality anti‐HIV approved kits. Furthermore, HIV serology testing selection was varied over the past six years as microplate‐based EIA was mostly used in the past but currently MBA and simple/rapid test are more commonly used. The test methods were determined by test volumes and budget. In addition, sensitivity was one critical reason labs chose to use EIA. The most popular method used was simple/rapid testing. Overall errors occurred with all assays but not with WB. Errors could occur with any test techniques if good quality management is not employed.

The winding, climbing roads of North Derbyshire still bore traces of the year's early snowfall, with mud‐splashed, hard‐packed drifts remaining by the roadside, when Circuit World visited LeaRonal on the outskirts of Buxton in December. At 1007 feet, Buxton is one of the highest towns in England. A spa and holiday resort, it is situated in the picturesque Peak District with its characteristic rocky crags, rugged moorlands and wooded dales. Britain's first national park—the Peak District National Park—covers some 540 square miles and it is at the edge of this leisure area that LeaRonal's High Peak Laboratories facility is located.

Ores and minerals are extracted from the earth’s crust depending on the type of deposit. Iron ore mines come under massive deposit patterns and have their own mine development and life cycles. This study aims to depict the development and life cycle of large open-pit iron ore mines and the intertwined organizational design of the departments/sections operated within the industry.

Primary data were collected on the site by participant observation, in-depth interviews of the field staff and executives, and field notes. Secondary data were collected from the literature review to compare and cite similar or previous studies on each mining activity. Finally, interactions were conducted with academic experts and top field executives to validate the findings. An organizational ethnography methodology was employed to study and analyse four large-scale iron ore mines of India’s largest iron-producing state, Odisha, from January to April 2023.

Six stages were observed for development and life cycle, and the operations have been depicted in a schematic diagram for ease of understanding. The intertwined functioning of organizational set-up is also discovered.

The paper will benefit entrepreneurs, mining and geology students, new recruits, and professionals in allied services linked to large iron ore mines. It offers valuable insights for knowledge enhancement, operational manual preparation and further research endeavours.

Some of the mechanisms involved in the microbial colonisation and biodeterioration of metalworking fluids are described in an attempt to design a more realistic and meaningful laboratory assay procedure. The history of bioassay techniques is reviewed and the nature and composition of metalworking fluids is examined. Maximisation of the performance of biocides against micro‐organisms and the influence of tramp oil contamination is assessed.

This paper considers the role of biosensors for monitoring the environment. A selection of existing products and competitive techniques such as biochemical assays and laboratory analysis which presently dominate the business are discussed. A number of research activities and themes are considered. Conclusion are drawn on the prospects for environmental biosensors.

The purpose of this paper was to use the barnacle Amphibalanus amphitrite reared in the laboratory to investigate the effects of juveniles on corrosion behaviour of three stainless steels (SS): UNS S31600, N08904 and UNS S32760.

Barnacle larvae were maintained in a laboratory until they reached the cypris larval stage. A total of 100 cyprids were added to four individual containers; each SS coupon (70 × 50 × 2 mm3) was immersed into the containers. After the cyprids attached to the coupons, juveniles were reared for 21 days with the microalgae Skeletonema costatum (Greville) Cleve. Values of open circuit potential (OCP), breakdown potential (Eb) and polarisation resistance (Rp) were evaluated, along with surface examinations.

OCP differences between barnacles and control coupons were not apparent. However, the lowest values of Eb and Rp were observed in the presence of juvenile barnacles, demonstrating the SS corrosion caused by these organisms. Crevice corrosion around the base of the barnacles was detected during visual inspections, despite the small size of the barnacles and the short duration of the experiments.

The A. amphitrite assays were useful as a tool for testing corrosion behaviour of the SS under laboratory conditions. This was the first study to test the use of this common protocol in anti-fouling research as a method to study marine biocorrosion.

“GIVE a dog a bad name and hang him,” is an aphorism which has been accepted for many years. But, like many other household words, it is not always true. Even if it were, the dog to be operated upon would probably prefer a gala day at his Tyburn Tree to being executed in an obscure back yard.

In the mining industry, a run-of-mine (ROM) stockpile is a temporary storage unit, but it is also widely accepted as an effective method to reduce the short-term variations of ore grade. However, tracing ore grade at ROM stockpiles accurately using most current fleet management systems is challenging, due to insufficient information available in real time. This study aims to build a three-dimensional (3D) model for ROM stockpiles continuously based on fine-grained grade information through integrating data from a number of ore grade tracking sources.

Following a literature review, a framework for a new stockpile management system is proposed. In this system, near real-time high-resolution 3D ROM stockpile models are created based on dump/load locations measured from global positioning system sensors. Each stockpile model contains a group of layers which are separated by different qualities.

Acquiring the geometric shapes of all the layers in a stockpile and cuts made by front wheel loaders provides a better understanding about the quality and quality distribution within a stockpile when it is stacked/reclaimed. Such a ROM stockpile model can provide information on predicating ore blend quality with high accuracy and high efficiency. Furthermore, a 3D stockyard model created based on such ROM stockpile models can help organisations optimise material flow and reduce the cost.

The modelling algorithm is evaluated using a laboratory scaled stockpile at this stage. The authors expect to scan a real stockpile and create a reference model from it. Meanwhile, the geometric model cannot represent slump or collapse during reclaiming faithfully. Therefore, the model is expected to be reconcile monthly using laser scanning data.

The proposed model is currently translated to the operations at OZ Minerals. The use of such model will reduce the handling costs and improve the efficiency of existing grade management systems in the mining industry.

This study provides a solution to build a near real-time high-resolution multi-layered 3D stockpile model through using currently available information and resources. Such novel and low-cost stockpile model will improve the production rates with good output product quality control.

Moringa oleifera (MO) is a herbal remedy that is rich in essential amino acids and phytochemicals in the leaves, seeds and pods. It is becoming a famous food in various ethnic groups, and the consumption is increasing worldwide. However, there is no safety profile of the hydroalcoholic MO leaf extracts, or documented teratogenicity aspect. This study was sought to compare the antioxidant activity and the teratogenicity of hydroalcoholic MO leaf extracts in the zebrafish embryo.

MO leaves were extracted with aqueous alcohols (ethanol or methanol: water, 80:20 v/v) using the Soxhlet method. The antioxidant capacity was determined using DPPH assay. The concentrations of extracts ranging from 3 to 1,000 µg/mL were used to examine the toxicity and teratogenicity on the zebrafish embryo.

Both hydroalcoholic MO leaf extracts were positive for alkaloids, terpenoids, steroids, tannins, flavonoids, phenols, coumarins, quinones and glycosides, except saponins only absent in aqueous methanol extract. The antioxidant capacity based on lC₅₀, was 15.92 ± 3.62 mg/mL for aqueous methanolic and 25.28 ± 2.89 mg/mL for aqueous ethanolic extract. For acute toxicity, the aqueous methanolic extract has lower LC₅₀ (163.87 ± 12.88 µg/mL) compared to aqueous ethanolic extract (337.48 ± 30.04 µg/mL). The embryo treated with aqueous methanolic extract showed phenotypic defect but not on the aqueous ethanolic extract.

This study suggests that aqueous methanol of MO leaves extract has better antioxidant capacity compared to ethanol, and ethanolic leaf extract is safer (higher LC50 and no teratogenicity) than methanolic extract.