Form error removal of sanded wood surfaces

The resistance of bacteria to some antibiotics is rampant nowadays. One of the genera of bacteria that has shown resistance to notable antibiotics is Staphylococcus aureus. Therefore, this study aimed at isolation of S. aureus from the soils and wooden table surfaces in some abattoirs within Ilorin, Nigeria. The objectives of this study were to determine the counts of heterotrophic bacteria in the soils and wooden table surfaces at some abattoirs in Ilorin, Nigeria; characterize and identify the S. aureus isolates; determine the antibiotic resistance patterns of the isolates; and detect the presence of spa, mecA, and mecC in the isolates. The counts of viable bacteria and S. aureus, antibiotic susceptibility as well as the physicochemical characteristics were determined using standard methods. The heterotrophic bacterial counts of the soils and wooden table surfaces ranged from 1.0 x 105 – 3.4 x 107 and 2.1 x 105 – 1.0 x 108 cfu/g respectively. In addition, the counts of S. aureus in the soils and wooden table surfaces ranged from 1.0 x 103 – 3.0 x 107 and 1.0 x 103 – 3.1 x 106 cfu/g respectively. The S. aureus isolates were positive for Gram staining, catalase, oxidase, mannitol fermentation and coagulase test. All the S. aureus were resistant to ampicillin, and ceftazidime, followed by augmentin (82%), vancomycin, cefuroxime, and nitrofurantoin (55% each); gentamicin and ciprofloxacin (36%) and ofloxacin (18%). None of the isolates possess mecA gene while mecC and spa genes were detected in 45.5 and 54.5% of the isolates respectively. This is the first study in which mecC gene was detected in any S. aureus in Nigeria. It is concluded from this study that the soils and wooden table surfaces from the abattoirs harboured S. aureus some of which possessed mecC for antibiotic resistance and the virulent factor, spa genes.

A bilateral comparison in moisture measurement between the National Institute of Metrology Thailand (NIMT) and the Central Bureau of Weights and Measures (CBWM) was organized for quality assuring of rice and paddy moisture measurement in Thailand. The bilateral comparison was conducted by using the same batch of sample and moisture meter as transfer device. It consisted of two parts: moisture measurement in rice and in paddy. A rice moisture meter belonging to CBWM and rice standards prepared at the nominal moisture content of 10 %, 12 %, 14 % and 16 % at NIMT, were used for rice moisture comparison, while a paddy moisture meter belonging to NIMT and paddy standards prepared at the nominal moisture content of 12 %, 14 %, 16 % and 18 % at CBWM, were used for paddy moisture comparison. Both laboratories measured the moisture content of a sample by using the standard method in ISO 712 and used that sample to calibrate a moisture meter by means of the method based on ISO 7700-1. Since the moisture content of the sample can change during the comparison, correction values in moisture content between the standard value and the reading value from the moisture meter are used as calibration results for the comparison evaluation. For the rice moisture comparison, differences in the correction value measured by the two laboratories vary from 0.18 % to 0.46 %, with their combined comparison uncertainty of 0.37 % ( $$\hbox {k}= 2)$$ . The main contribution to the difference comes from the standard values from both laboratories differing from 0.27 % to 0.53 %, as the rice standard was found to drift in moisture content less than 0.05 %. Similarly to the rice moisture comparison, differences in the correction value for the paddy moisture measurement range from 0.08 % to 0.56 % with the combined comparison uncertainty of 0.38 % ( $$\hbox {k} = 2)$$ , whereas the stability in moisture content of the paddy sample at NIMT was found to be within 0.12 %.

Remarkable interest for human health concerns the microbiological risk assessment due infections by bacteria possessing the ability to adhere to host cell or abiotic surfaces as well as to live in aggregated and biofilm lifestyle. Biofilm is multicellular bacterial community held together by a self-produced extracellular matrix in response to several factors. These factors may include recognition of specific or non-specific attachment sites on cell surfaces, electrostatic interactions on abiotic surfaces, nutritional cues, or in some cases, exposure to stress conditions in the environment as well as into the host. Biofilm lifestyle is comparatively more common than the planktonic one and it has been shown that biofilm plays a crucial role in human health (Brady et al., 2008; Bryers, 2008). As matter of fact, the eradication of bacterial biofilm by administration of antibiotics often fails due to the high drug resistance of bacteria in this lifestyle. Since 2008, European Centre for Disease Prevention and Control reports epidemiological data on the increasing of antimicrobial resistance constituting an important concern in public health hazard. For this reason, rapid assays to determine biofilm susceptibility to antibacterial drugs can significantly improve the outcome of infected patients by enabling a fast selection of efficient antibiotic treatments, thus decreasing the period and the related costs of hospitalization, as well as the incidence of morbidity and mortality ( Gfeller et al., 2005). Therefore, a fundamental prerequisite in studying, counteracting and eradicating biofilm is the possibility to quantify the actual number of bacteria involved. Bacterial counts have deep implications in microbiological diagnosis and therapeutic treatments (Bryers, 2008), in water and food quality analysis (Ramalho et al., 2001; Lee et al., 2007; Rueckert et al., 2005), in environmental applications and consumers’ safety. The standard method used to evaluate the number of bacteria, based on determination of Colony Forming Units (CFUs) (ISO method), can be considered fully appropriate only when bacteria are in planktonic lifestyle but it is unreliable to count bacteria in aggregated, adherent and biofilm lifestyle (Berlutti et al., 2003, Pantanella, 2008; Berlutti, 2008 a; Frioni,

Soil DNA extraction has become a critical step in describing microbial biodiversity. Historically, ascertaining overarching microbial ecological theories has been hindered as independent studies have used numerous custom and commercial DNA extraction procedures. For that reason, a standardized soil DNA extraction method (ISO-11063) was previously published. However, although this ISO method is suited for molecular tools such as quantitative PCR and community fingerprinting techniques, it has only been optimized for examining soil bacteria. Therefore, the aim of this study was to assess an appropriate soil DNA extraction procedure for examining bacterial, archaeal and fungal diversity in soils of contrasting land-use and physico-chemical properties. Three different procedures were tested: the ISO-11063 standard; a custom procedure (GnS-GII); and a modified ISO procedure (ISOm) which includes a different mechanical lysis step (a FastPrep ®-24 lysis step instead of the recommended bead-beating). The efficacy of each method was first assessed by estimating microbial biomass through total DNA quantification. Then, the abundances and community structure of bacteria, archaea and fungi were determined using real-time PCR and terminal restriction fragment length polymorphism approaches. Results showed that DNA yield was improved with the GnS-GII and ISOm procedures, and fungal community patterns were found to be strongly dependent on the extraction method. The main methodological factor responsible for differences between extraction procedure efficiencies was found to be the soil homogenization step. For integrative studies which aim to examine bacteria, archaea and fungi simultaneously, the ISOm procedure results in higher DNA recovery and better represents microbial communities.

In this study to certify the BAX for Screening/Listeria monocytogenes assay (DuPont Qualicon, Wilmington, DE), an internal evaluation was conducted on 16 food types that were simultaneously analyzed with the BAX system (BAX), and the ISO method for the detection of L. monocytogenes (ISO). No statistically significant difference in performance between the BAX and ISO methods was observed. Inclusivity/exclusivity testing showed that the BAX system was able to detect 97 of 97 (100%) of L. monocytogenes strains tested. None of 56 other Listeria species or non-Listeria tested gave a reproducible positive BAX result. Ruggedness testing demonstrated that performance of the assay was not affected by reasonable variability in the operating parameters. BAX was then submitted for independent laboratory validation. In this phase, BAX was compared with standard culture methods for the detection of L. monocytogenes in chicken (USDA-FSIS), crab meat (BAM), and milk (AOAC). This study validated product claims of sensitivity and specificity >98% in accordance with AOAC Performance Tested Method requirements.

During 1995 fiscal year, the National Laboratories of Foods and Drugs were commissioned to study the standard analytical methods and to conduct an annual survey of nicotine and tar yields of domestic and imported cigarettes. The objective was to provide a reference for the health authorities. In 1997, 324 samples of domestic and imported cigarettes were analyzed in compliance with ISO methods. Nicotine yields of domestic cigarettes ranged from 1.24 to 2.06 mg/cig and averaged 1.62 mg/cig. Corresponding tar yields ranged from 11.68 to 18.43 mg/cig and averaged 15.83 mg/cig. Nicotine yields of 42 imported brands ranged from 0.50 to 2.95 mg/cig and averaged 1.09 mg/cig, with corresponding tar yields ranging from 5.63 to 31.04 mg/cig and averaging 12.75 mg/cig. Thus both nicotine and tar yields of domestic cigarettes have reduced (since 1996), average yields were still higher than those of the imported cigarettes. Nicotine and tar yields of 4 imported cigarette brands were relatively high. According to a Health Department mandate, in 2001 the nicotine and tar yields in tobacco products shall not exceed 1.5 mg/cig and 15 mg/cig, respectively. By 2007, these upper limits will be further reduced to 1.2 mg/cig and 12 mg/cig. The tar and nicotine contents of several brands, both domestic and imported, will need to be reduced before the Health Department's new regulations come into effect.

Evaluation of real-time PCR coupled with immunomagnetic separation or centrifugation for the detection of healthy and sanitizer-injured Salmonella spp. on mung bean sprouts

Listeria monocytogenes is frequently found as a contaminant in raw and ready-to-eat foods. The ability of L. monocytogenes to multiply at refrigeration temperatures and to grow in a wide range of pH values is of particular concern for food safety. According to the European Union regulation on microbiological criteria for foodstuffs, L. monocytogenes must be absent in some categories of ready-to-eat foods. The standard microbiological method for L. monocytogenes detection in foods (ISO 11290-1: 1996 (ISO, International Organization for Standardization)) is cost and time consuming. Developments of rapid, cost-effective and automated diagnostic methods to detect food-borne pathogens in foods continue to be a major concern for the industry and public health. The aim of this study was the development of a rapid, sensitive and specific molecular detection method for L. monocytogenes. To this purpose, we have applied a capillary electrophoresis method to a PCR protocol (PCR-EES (EES, experion automated electrophoresis system)) for detecting L. monocytogenes in food. In particular, a microfluidic chip-based automated electrophoresis system (experion automated electrophoresis system, Bio-Rad Laboratories, USA) was used for the rapid and automatic analysis of the amplicons. Fifty naturally contaminated samples were analysed with this method and the results were compared with those obtained with ISO method. Moreover, the microfluidic chip-based automated electrophoresis system was compared with classical gel electrophoresis (PCR-CGE). The results showed that after 24 h of culture enrichment, the PCR-EES showed a relative accuracy of 100% with ISO, while using PCR-CGE decreased it down to 96%. After 48 h of enrichment, both PCR-EES and PCR-CGE showed an accuracy of 100% with ISO.

South African laboratories are currently using various methods in a non-standardised approach to detect Legionella species in environmental samples. In an attempt to provide guidelines for the development of a standard method, a number of currently available detection methods were evaluated, using seeded samples of sterile and non-sterile tap water, cooling water and make-up water. The samples were seeded with a type strain of L. pneumophila serogroup 1 (American Type Culture Collection 33152). The effect of sample concentration by centrifugation and membrane filtration followed by either vortex or sonication for resuspension of organisms was studied. Three currently available culture methods were evaluated: the International standard method (ISO/DIS 11731), the Australian standard method (AS 3896 - 1991) and a locally-developed adaptation of the most probable number method (MPN). In addition, the direct immunofluorescence test and a commercially available latex agglutination test kit were included in the evaluations. The usefulness of treatment with acid or heat prior to culture was also compared. Our results indicated that concentration by membrane filtration using nitro-cellulose filters with a pore size of 0.45 ?m, followed by sonication for 10 min, would be the most appropriate concentration and resuspension method for the samples. In the absence of sample pretreatment with acid or heat, organism recovery from sterile seeded samples on BCYE ranged from 85.9 - 98.7%. However, in the non-sterile samples, these figures dropped to 8.1 - 38.5%. Sample pretreatment resulted in a further loss of at least 50% of organisms in all the samples, regardless of the pretreatment method or culture medium used. In general, the ISO and AS methods were more appropriate than the MPN method for organism recovery from sterile seeded samples. However, for the nonsterile samples, the MPN method yielded better recovery. WaterSA Vol.27(4) 2001: 523-528

Standard polynomial fitting methods are inconsistent in their formulation. The regional field is approximated by a polynomial fitted to the observed field. As a result, in addition to the nonuniqueness in the definition of the regional field, the fitted polynomial is strongly influenced by the residual field (observed field minus regional field). We present a regional-residual separation method for gravity data which uses a robust procedure to determine the coefficients of a polynomial fitted to the observations. Under the hypothesis that the regional can be modeled correctly by the polynomial surface, the proposed method minimizes the influence of the residual field in the fitted surface.The proposed method was applied to real gravity data from Ceara state, Brazil, and produced information on zones of possible crustal thickening and the occurrence of lower-crustal granulitic rocks thrust into the shallow subsurface.

Xylem anatomy is fundamental in studies of the evolution of terrestrial plants, tree ecophysiology, forestry, and wood science. Traditional xylem anatomical studies by light microscopy utilize wood sections. However, the procedures are laborious, and high-quality histological sections have been particularly challenging to achieve from recalcitrant wood species and dry wood material. Modern microscopy offers opportunities for speeding up the xylem anatomical preparations. In this regard, the merits of using a sanded surface for wood anatomical research have been largely overlooked. Sanding of wood surfaces is practiced in dendrochronology and wood identification studies exclusively for the investigation of macro features, such as tree rings, wood porosity, or parenchyma patterns. We conducted microscopic level investigations of sanded surfaces of difficult-to-section high-density woods such as Dalbergia and Quercus species by reflected white light and epifluorescence microscopy. Reflected white light or combinations of reflected light and fluorescence could clearly show xylem micro-features in sanded wood surfaces. The resolution of cell types after sanding with 1000-grit was similar to the resolution obtained by transmitted light microscopy in histological slides. The advantages of sanded wood surfaces compared to traditional wood sections can be summarized as cost- and time-effective sample preparation, large sample area, intact cell walls and tissue structure, preservation of chemical content and extractives, and even focus of the field of view. A simple procedure of wood sanding instead of microscopic slides can be used for xylem microscopy and automatic image analysis of xylem structure.

Chronologies of earlywood vessel size of ring- porous trees contain valuable ecological information, but long preparation procedures limit their application in eco- logical studies. Recent and fast techniques for wood surface preparation combined with automated image analysis are reducing the work needed to build chronolo- gies, but might also entail measurement inaccuracy. In this study, we aim to evaluate the effect of a possible effi- ciency-accuracy trade-off on ecological signal strength. To this end, we compare measurements of mean vessel area from two recent and fast procedures carried out on sanded wood surfaces with a reference procedure based on an accurate survey from thin sections. Measurements were performed on increment cores of 15 sessile oaks (Quercus petraea (Mattuschka) Liebl.) for the period 1956-2006. Dissimilarities in results with the reference procedure were quantified and evaluated. Our data show that the workload can be reduced by more than 20-fold when using the highly automated procedure. Signal weakening caused by mea- surement errors is negligible for vessels (6,000 lm 2 and can be easily compensated by increasing the sample size. Manual correction of misrecognized vessels hardly reduced this error further. The new procedures constitute a major step towards an efficient and accurate analysis of early- wood vessel chronologies of ring-porous tree species.

In this day of digitalization, you can work within the technology of optics without having to fully understand the science behind it. However, for those who wish to master the science, rather than merely be its servant, it's essential to learn the nuances, such as those involved with studying fringe patterns produced by optical testing interferometers.When Interferogram Analysis for Optical Testing originally came to print, it filled the need for an authoritative reference on this aspect of fringe analysis. That it was also exceptionally current and highly accessible made its arrival even more relevant. Of course, any book on something as cutting edge as interferogram analysis, no matter how insightful, isn't going to stay relevant forever. The second edition of Interferogram Analysis for Optical Testing is designed to meet the needs of all those involved or wanting to become involved in this area of advanced optical engineering. For those new to the science, it provides the necessary fundamentals, including basic computational methods for studying fringe patterns. For those with deeper experience, it fills in the gaps and adds the information necessary to complete and update one's education. Written by the most experienced researchers in optical testing, this text discusses classical and innovative fringe analysis, principles of Fourier theory, digital image filtering, phase detection algorithms, and aspheric wavelength testing. It also explains how to assess wavefront deformation by calculating slope and local average curvature.

Disinfection of foot-and-mouth disease and African swine fever viruses with citric acid and sodium hypochlorite on birch wood carriers

The metrology of processed wood surfaces is complex due to the presence of wood anatomical cavities, which are a factor of bias in several metrological steps, from the measuring to the evaluation of the surface quality. Wood requires special recommendations, and one regards the use of a robust Gaussian regression filter for filtering the roughness. The filter was previously tested with success on wood surfaces and was used in this paper. Furthermore, a reliable quantification of the processing roughness requires that independent wood anatomical data be removed from the evaluation. The paper presents a method of separating the roughness induced by processing from the wood anatomical structure. It was tested on different wood species, sanded with various grit sizes, and on a plastic material included for comparisons. The results showed similar values of the processing roughness for materials sanded with the same grit size, in spite of their different structures. The method could further be used for optimization of processing parameters at sanding.