Visual Examination Method Research Articles

Diagnosis of Pressure Ulcer Stage Using On-Device AI

Pressure ulcers are serious healthcare concerns, especially for the elderly with reduced mobility. Severe pressure ulcers are accompanied by pain, degrading patients’ quality of life. Thus, speedy and accurate detection and classification of pressure ulcers are vital for timely treatment. The conventional visual examination method requires professional expertise for diagnosing pressure ulcer severity but it is difficult for the lay carer in domiciliary settings. In this study, we present a mobile healthcare platform incorporated with a light-weight deep learning model to exactly detect pressure ulcer regions and classify pressure ulcers into six severities such as stage 1–4, deep tissue pressure injury, and unstageable. YOLOv8 models were trained and tested using 2800 annotated pressure ulcer images. Among the five tested YOLOv8 models, the YOLOv8m model exhibited promising detection performance with overall classification accuracy of 84.6% and a mAP@50 value of 90.8%. The mobile application (app) was also developed applying the trained YOLOv8m model. The mobile app returned the diagnostic result within a short time (≒3 s). Accordingly, the proposed on-device AI app can contribute to early diagnosis and systematic management of pressure ulcers.

Operator, patient and parental Level of acceptance between Visual Intraoral Examination and Intraoral Camera in Seven to Twelve year Old Children

Introduction There are variety of methods for intraoral examination, visual examination being the most popular method. Intraoral camera is one of the innovative technologies which are being developed. Materials and Methods Thirty 7-12 year old children were examined using both the methods and a self-administered questionnaire was administered to them. Fifteen operators were also given a questionnaire. Quantitative data was expressed as frequency with percentages and qualitative data was analysed through thematic analysis. Results 87 % children and 63 % parent preferred Intraoral camera over Visual examination method. Operators preferred visual examination for diagnosis and Intraoral camera for patient and parental education. Conclusions Oral examination using Intraoral camera was perceived positively and preferred by children and parents. As Paediatric dentists, we can use Intraoral camera along with the visual oral examination method. Key Words Children, Intraoral camera, Visual oral examination

Studying an improved recursive rough method for three-dimensional visual examination of steel plate butt welding surface quality

An improved recursive rough algorithm is proposed to extract feature points in order to address the slow speed and poor accuracy of feature point extraction in 3D visual inspection, as well as the difficulty in meeting the requirements of efficient and quantitative analysis of welded surface quality detection. The preprocessed point cloud is sliced by section. The feature points are obtained according to the improved recursive rough algorithm. The defect evaluation is carried out to obtain the inspection conclusion of the weld appearance defect. Finally, according to the formulated weld defect evaluation process and standards, the typical weld template is selected for weld width, weld misedge and weld straightness test. Weld detection accuracy can reach 3 decimal places, the speed is 4 times the current manual detection speed. The detection results show that the system has the characteristics of high accuracy and fast speed which can replace manual detection. It also has a good application prospect.

Comparative evaluation of visual-palpatory findings with scrotal doppler ultrasound data for varicocele diagnosis

Introduction. Current evidence suggests that management of any grade of varicocele can improve male fertility. However, diagnosis of grade 1 varicocele in infertile men without the use of scrotal Doppler ultrasound may cause overtreatment.Objective. To study the comparability and accuracy of the visual palpatory examination method with the scrotal Doppler ultrasound data for the diagnosis of varicocele.Material & methods. Between November 2005 to January 2022, 2871 patients diagnosed with varicocele and infertility who underwent microsurgical varicocelectomy by inguinal access were examined at RSSPMCU. The average age of the patients was 30.16 ± 0.09 (18 – 60) years. Of the 2871 patients, 2592 (90.3%) were diagnosed by physical examination, and 279 (9.7%) patients underwent additional scrotal Dopper ultrasound.Results. After Doppler scrotal imaging was introduced into practice, the proportion of patients with bilateral varicocele increased from 32.2% to 61.6% (p < 0.01). The proportion of patients with right-sided varicocele also increased significantly. Experienced physicians during physical examination of infertility patients did not diagnose grade 1 varicocele in 4.3%.Conclusions. The implementation of scrotal Doppler ultrasound for the diagnosis of male infertility improved the detection of grade 1 varicocele and bilateral varicocele. In turn, this contributed to earlier elimination of the male factor of infertility in this contingent of patients.

Reliability of gaze-contingent perimetry.

Standard automated perimetry, a psychophysical task performed routinely in eyecare clinics, requires observers to maintain fixation for several minutes at a time in order to measure visual field sensitivity. Detection of visual field damage is confounded by eye movements, making the technique unreliable in poorly attentive individuals and those with pathologically unstable fixation, such as nystagmus. Microperimetry, which utilizes 'partial gaze-contingency' (PGC), aims to counteract eye movements but only corrects for gaze position errors prior to each stimulus onset. Here, we present a novel method of visual field examination in which stimulus position is updated during presentation, which we refer to as 'continuous gaze-contingency' (CGC). In the first part of this study, we present three case examples that demonstrate the ability of CGC to measure the edges of the physiological blind spot in infantile nystagmus with greater accuracy than PGC and standard 'no gaze-contingency' (NoGC), as initial proof-of-concept for the utility of the paradigm in measurements of absolute scotomas in these individuals. The second part of this study focused on healthy observers, in which we demonstrate that CGC has the lowest stimulus positional error (gaze-contingent precision: CGC = ± 0.29°, PGC = ± 0.54°, NoGC = ± 0.81°). CGC test-retest variability was shown to be at least as good as both PGC and NoGC. Overall, CGC is supported as a reliable method of visual field examination in healthy observers. Preliminary findings demonstrate the spatially accurate estimation of visual field thresholds related to retinal structure using CGC in individuals with infantile nystagmus.

Visual assessment of soil structural quality across soil textures and compaction levels – Part I: Examination of intact soil cores

Soil structural degradation has become very common and leads to a serious decline in soil health. Improving or maintaining soil structure is key to build resilience against drought and flooding, and thus contributes to assuring food and water security. Quantification of soil structural quality is usually accomplished by traditional laboratory-based methods, which are time-, labour- and money-consuming. Visual soil evaluation and examination methods comprise rapid and simple tests that offer a numeric semi-quantitative assessment of soil structure. The common criteria are aggregate size and shape, ease of break or rupture resistance, and inter- or intra-aggregate porosity. In this study, the CoreVESS method, a variant of the Visual Evaluation of Soil Structure (VESS) method originally developed for topsoil assessment, was applied on 250 cm3 undisturbed soil core samples. Resulting soil quality scores (Sq, ranging between 1, good, and 5, poor) were compared with soil quality indicators (SQi) derived from traditional quantitative methods of soil structure analysis. Tested SQi’s included penetration resistance, bulk density, soil hydraulic properties, soil organic carbon and texture (percentage of clay, silt and sand). The objective of the study was to assess and quantify the state of soil structural degradation induced by agricultural operations using a suite of methods of analysis at a regional scale, with a special focus on CoreVESS. Soil core samples were taken in Belgium from 42 cropped fields, at two positions (headland and in-field zone) and from three layers, notably the ploughed topsoil (TOP, 10–20 cm), the compacted subsoil (CSUB, 30–40 cm) and the deeper subsoil (SUB, 60–70 cm), totalling the sample horizons to 252. Test and sampling sites comprised all major soil texture classes within the Belgian soil textural triangle and varied from sand to heavy clay. In-field positions (IN-FIELD) showed significantly better coreVESS-based Sq scores as compared to headland positions (HEAD), with the CSUB layers always exhibiting significantly lower quality than the other two layers. Laboratory-derived soil quality indicator (SQi) values portrayed the same trend, with CSUB layers always indicating the poorest soil quality. Significant differences in SQi’s were also found between soils of acceptable (Sq ≤ 3) and degraded (Sq > 3) structure. Likewise, grouping soils into the same categories resulted in significant differences in the soil water retention and hydraulic conductivity curves in their wet ranges. There were good significant relationships between the SQi values and CoreVESS-based Sq scores, with for example Pearson R correlation coefficients of 0.64 for both penetration resistance and bulk density. Also, Sq scores related well with an SQi-based soil quality index (SQI) value averaged per layer and texture class (Pearson R of 0.60). The study confirmed that agricultural operations and their intensity clearly affect soil structural quality across various soil textures, with CoreVESS being as responsive to variation in soil structure quality as traditional quantitative methods, even when applied in the subsoil. VESS methods thus have a potential for monitoring soil structural quality over a variety of textures in a rapid, intuitive, practical and cheap way, as an alternative for or being complementary to more expensive labour-intensive traditional quantitative methods.

Pilot study of tolerability and safety of combination product containing terbinafne hydrochloride and econazole nitrate

Therapy of onychomycosis today presents a number of diffculties, and the effect does not always meet the expectations of patients. The purpose of the study. To study the tolerability and safety of the use of the drug Exilac(terbinafne hydrochloride + econazole nitrate), medical nail polish for external use. Methods. Eighteen volunteers participated in a pilot, prospective, monocentre, open-label tolerability and safety study. The study lasted 6 weeks and consisted of screening and fve visits, at each visit a visual examination, laboratory and instrumental examination methods were performed. Results. Eighteen healthy volunteers aged 18 to 34 participated in the study. Adverse events associated with the application of the study drug Exilac were observed in 1 (5.56%) volunteer, in the form of signs of delamination of the nail plate of the 1st fnger. This phenomenon is associated with mechanical damage to the nail plate when removing the old layer of the study drug and was regarded as a minor adverse event of mild severity. The remaining adverse events were not related to the use of the drug. Conclusion. The combined drug Exilac, when used twice daily for 6 weeks, demonstrated a high level of tolerability and safety.

Measurement uncertainty for detection of visual impurities in granular feed and food materials in relation to the investigated amount of material

The presence is regulated of visually detectable seeds from a selection of toxic plants and fungi mycelium bodies (sclerotia) in feed (Directive 2002/32/EC) and in food (Regulation (EC) 1881/2006). Homogenisation as typical for chemical analyses is not applicable, and dedicated approaches are needed for visual examination methods. Visual methods require two parameters to characterise measurement uncertainties for both unit counts and unit weights. A new approach is to divide approximately 2 kg of sample material into four subsamples of approximately 500 g and to separately examine the four subsamples for numbers and particle weights of seeds or sclerotia. This study is the first to produce datasets on inhomogeneity among subsamples of a sample for visually detectable undesirable substances. Analytical thresholds were calculated from a simulation model and bootstrap procedures based on our data. The analytical thresholds assuring a controlled false-negative rate of 5% for decisions in compliance with legal limits depend on the diversity of the unit counts and weights, the level of the legal limit and the amount of material examined initially in the step-wise approach, either one or two subsamples. A procedure is proposed for examination in practice where only two subsamples, or alternatively even only one subsample, would be examined. If the resulting level of contamination exceeds the relevant threshold additional subsamples need to be examined as well. In most of the investigated cases, analytical thresholds could be established for the examination of just one subsample (500 g) taken from a sample of 2 kg. However, for ergot sclerotia in food with a legal limit of 200 mg kg−1, at least two subsamples (1000 g) need to be examined in the first step. Other groups of visually detectable undesirable substances exist which need further attention.

Hidden Markov models for detection of Mysticetes vocalisations based on principal component analysis

ABSTRACT The economic relevance of Mysticetes has prompted marine ecologists and biologists to investigate this suborder of cetaceans. Mysticetes produce distinct vocal repertoires, which are recorded to analyse the behaviour of the species within its ecology. Passive acoustic monitoring (PAM) is a standard technique for tracking Mysticete movement and vocalisation. PAM collects enormous datasets over a long period, making it practically impossible to analyse with typical visual examination methods. Machine learning (ML) techniques such as hidden Markov models (HMMs) have made automatic recognition and analysis of extensive sound recordings possible. Nevertheless, the performance of ML tools is determined by the adopted feature extraction technique. Hence, this article introduces the method of principal component analysis (PCA) as a performance-efficient alternative feature extraction technique for detecting Mysticete vocalisations using HMM. Performance of the developed PCA-HMM detector is compared with state-of-the-art detectors using two different Mysticete vocalisations (Humpback whale songs and Bryde’s whale short pulses). In both species, results show that the PCA-HMM detector has the best performance and is more suitable for use in real-time application since it exhibits less computational time complexity.

Seasonal Incidence of Ectoparasitic mites and Greater Wax Moth in Apis mellifera L. Colonies

The incidence of ectoparasitic mites Varroa destructor (Anderson and Trueman), Tropilaelaps clareae (Delfinado and Baker) and wax moth Galleria mellonella (L.) on the honey bee Apis mellifera L. was assessed during 2019-20 at the Krishi Vigyan Kendra, Morena, Madhya Pradesh. The results revealed that V. destructor infestation was at minimum (4%) in the first fortnight of July 2019 and maximum (14%) in the first fortnight of September 2019 with the visual examination method. There existed a negative correlation with the brood area. Tropilaelaps clareae infestation was minimum (6 mites/colony) in the second fortnight of November 2019 and maximum (22 mites/colony) during the first fortnight of October 2019, as assessed by the sugar dusting method. The infestation revealed a negative correlation with colony strength. Galleria mellonella incidence was at maximum (176 larvae, 72 pupae, and 17 adults/colony) in the second fortnight of September 2019 and minimum (5 larvae, 5 pupae, and 2 adults/colony) in the first fortnight of September, August and August 2019, respectively. The number of pupae and brood area was found significantly negatively correlated (r = -0.534); while the number of adults vs. colony strength and brood area were significantly negatively correlated (r = -0.499 and r = -0.607, respectively).

Shifting Feeding Habits During Settlement Among Small Yellow Croakers (Larimichthys polyactis)

The small yellow croaker, Larimichthys polyactis, is a keystone species in the Yellow Sea and the East China Sea, with significant impacts on the regional ecosystem, but has experienced decades of population decline as a result of environmental changes and overfishing. The settlement of post-larval L. polyactis is a period of high mortality, with impacts on population recruitment and survival. This study examines the feeding habits of 49 post-larval and early juvenile L. polyactis in the Yangtze River estuary, in order to reveal diet composition before and after the settlement period. DNA barcoding methods (MiSeq and TA cloning) were used to examine gastrointestinal contents in detail. Both methods revealed that dietary breadth increased with increasing body length, while the dominance of copepods in the diet decreased as the body length increased. Post-larva (body length < 17 mm in this study) primarily fed on copepods. At the beginning of settlement (body length between 17 and 19 mm), L. polyactis began to ingest larger organisms, such as fishes and mysids, along with copepods. Larger early juveniles (body length > 20 mm) demonstrated a much wider dietary breadth, implying that successful settlement had occurred. Diet species richness in the MiSeq group was significantly greater than species richness in the TA cloning group, making the trend more pronounced within the MiSeq group. This indicates that the MiSeq method was more efficient than TA cloning in this study. We recommend that future research to investigate the feeding habits of fish larvae should combine MiSeq and visual examination methods.

Nilai-Nilai Shintoisme pada Perbedaan Warna dan Bentuk Gerbang Dunia Dewa di Awal dan Akhir Film Spirited Away Karya Studio Ghibli

Spirited Away is an animation made by Ghibli Studio on 2001 under Hayao Miyazaki direction. This movie awarded as The Best Animation by The 75th Academy Award. This movie tells about the journey of Chihiro, the protagonist who’s been “spirited away” to the spirit world. There’s a significant difference on the visual and surounding of the scene when Chihiro went inside the spirit world through the gate in the beginning of the movie and when she’s back from that world at the ending. Even it’s pretty clear that it is the same place, but the gate, the colors, material, and the environment seems to be different. This visual generate a long controversy, include of how excactly the story end. Question arise of the significant distinction on the visual of the gate between the scenes, like why on the beginning the color of the gate is red with some characteristic of Shinto’s Temple architectural, but then the gate at the ending is white and made from stone piles. Hayao Miyazaki as creator of the movie has never explicitely answer the question on this matter. This qualitative study using visual examination method on colors and material of the gates, from the perspective of Shinto’s and Japanese architecture, to know the reason behind the importance of differentiating the visual of the gates in the beginning and the ending of the movie.

Oral Autopsy – Dental Surgeon’s Perspective

Background: Autopsy is routinely performed by the coroner in all medico-legal cases but the dental expertise is rarely sought. However, oral autopsy involving careful visual examination, imaging and laboratory methods can aid in solving the enigma associated with legal aspects of crime scene and death investigation. Aim: To illustrate the importance of oral autopsy during routine post-mortem examination. Data Sources: Pub-Med, Google Scholar search engines were used to extract the data. Conclusion: Oral autopsy performed as an adjuvant to regular autopsy procedure will definitely benefit in the legal investigation related to visually identifiable, decomposed, burnt or skeletonized corpse.

Network Visualization and Pyramidal Feature Comparison for Ablative Treatability Classification Using Digitized Cervix Images

Uterine cervical cancer is a leading cause of women’s mortality worldwide. Cervical tissue ablation is an effective surgical excision of high grade lesions that are determined to be precancerous. Our prior work on the Automated Visual Examination (AVE) method demonstrated a highly effective technique to analyze digital images of the cervix for identifying precancer. Next step would be to determine if she is treatable using ablation. However, not all women are eligible for the therapy due to cervical characteristics. We present a machine learning algorithm that uses a deep learning object detection architecture to determine if a cervix is eligible for ablative treatment based on visual characteristics presented in the image. The algorithm builds on the well-known RetinaNet architecture to derive a simpler and novel architecture in which the last convolutional layer is constructed by upsampling and concatenating specific RetinaNet pretrained layers, followed by an output module consisting of a Global Average Pooling (GAP) layer and a fully connected layer. To explain the recommendation of the deep learning algorithm and determine if it is consistent with lesion presentation on the cervical anatomy, we visualize classification results using two techniques: our (i) Class-selective Relevance Map (CRM), which has been reported earlier, and (ii) Class Activation Map (CAM). The class prediction heatmaps are evaluated by a gynecologic oncologist with more than 20 years of experience. Based on our observation and the expert’s opinion, the customized architecture not only outperforms the baseline RetinaNet network in treatability classification, but also provides insights about the features and regions considered significant by the network toward explaining reasons for treatment recommendation. Furthermore, by investigating the heatmaps on Gaussian-blurred images that serve as surrogates for out-of-focus cervical pictures we demonstrate the effect of image quality degradation on cervical treatability classification and underscoring the need for using images with good visual quality.

Use of a gene encoding zona pellucida 4 as a female-specific marker for early stage sexual differentiation and size dimorphism in the pacific abalone Haliotis discus hannai

Growth rates of Pacific abalone Haliotis discus hannai are an important trait affecting the economic value in the abalone aquaculture industry. A reverse-transcription polymerase chain reaction (RT-PCR) analyses of tissues from H. discus hannai was conducted for sexually mature gonads to determine male- and female-specific target gene expression, including genes encoding zona pellucida domain 4 (zp4), sperm protein (sp) and lysin (lys), respectively. Sex-specific expression patterns of these gene expression, even in sexually immature abalone, indicate these genes can be used as sensitive and robust sex-specific molecular markers. The RT-PCR procedure was also performed to analyze tissues collected at various developmental stages (50-day intervals) beginning at fertilization to determine when sex differentiation and expression of sex-specific genes was initiated. Detection of zp4 transcript in tissues collected at 200 days post-fertilization (dpf) indicated egg-specific development starts at 150–200 dpf. To evaluate possible sex-specific differences in growth rate, there was conducting of a molecular marker-based sex identification of abalone from a population selected for rapid growth rate. In a group of large H. discus hannai, females were more prevalent than males. To assess the correlation between growth and sex, there was comparison of weights of 3-year-old Pacific abalone in specimens where there had been sex determinations by visual examination and molecular methods. The results indicated females weighed more (55.92 ± 9.38 g, n = 15) than males (43.64 ± 15.55 g, n = 6, P = 0.037), indicating females had a more rapid growth rate than males.

What diagnostic strategy performs better for caries lesion detection on proximal surfaces of adolescents?

To evaluate the performance of visual inspection alone and associated to radiographic and laser fluorescence (LF) methods in detecting non-evident caries lesions at adolescents' proximal surfaces. Adolescents (12 to 17years old) were assessed for the presence of caries lesions through visual inspection, radiographic examination, and LF method (DIAGNOdent pen), at non-cavitated (NC) and cavitated lesion (CAV) thresholds. Temporary separation with orthodontic rubbers followed by direct visual inspection was the reference standard method. Two examiners conducted the examinations, and the first examiner reassessed around 20% of the sample, to evaluate inter- and intra-examiner reproducibility, respectively. Sensitivity, specificity, accuracy, and utility values were calculated for the methods alone and combined with visual inspection using two different strategies: simultaneous and sequential combination. A total of 834 proximal surfaces (51 adolescents) were included. Visual inspection presented higher reproducibility values (higher than 0.98). Moreover, visual inspection presented higher sensitivity (around 0.51) than those obtained with other diagnostic strategies (varying from 0.09 to 0.20) at the NC threshold. For CAV, visual inspection presented higher specificity (0.996) than the sequential association with adjunct methods (around 0.97), but with lower sensitivity. Accuracy and utility values for combined strategies were similar or lower than those achieved with the visual inspection performed alone. Visual inspection alone performs better for detecting caries lesions in premolars and molars of adolescents than other diagnostic strategies. The best diagnostic strategy for caries detection of proximal caries lesions in adolescents is the visual inspection alone.

An In Vivo Investigation of Diagnostic Performance of DIAGNOdent Pen and the Canary System for Assessment and Monitoring Enamel Caries under Fissure Sealants.

ABSTRACTAim and Objectives:The aim of this study was to evaluate and compare the diagnostic performance of a quantitative light-induced fluorescence (DIAGNOdent pen [DP]) and a photothermal radiometry (Canary System [CS]) for assessment and monitoring occlusal enamel caries under fissure sealants placed on young permanent teeth.Materials and Methods:Forty-five patients of mean age 9.96 (1.4) years, having at least two occlusal surface sites of non-cavitated lesions (International Caries Detection and Assessment System [ICDAS], 1–3 at baseline), were assigned for this clinical study as per specific inclusion/exclusion criteria. A total of 90 permanent teeth were examined using a visual examination method (ICDAS), a quantitative light-induced fluorescence (DP), and a photothermal radiometry (CS). Teeth were randomly divided into two groups based on the type of fissure sealants: a resin sealant and a glass-ionomer sealant. Sealants were placed over the study sites, and caries assessment was performed with each caries detection method at 3- and 6-month recall appointments. Numerical data were presented as mean, standard deviation, median, and interquartile range values. Qualitative data were presented as frequencies and percentages. Receiver operating characteristic (ROC) curve was constructed to determine the diagnostic accuracy measures of the two modalities and compared using z-statistic. ROC curve analysis was performed with MedCalc software, Ostend, Belgium, version 11.3 for Windows (MedCalc Software). Changes by time in caries progression were analyzed using McNemar test and Cochran Q test. The significance level was set at P ≤ 0.05. Statistical analysis was performed with the IBM Statistical Package for the Social Sciences (SPSS) software for Windows, version 23.0 (IBM, Armonk, New York).Results:The CS and DP were able to distinguish between sound and carious tissue beneath fully and partially retained sealants at 6-month follow-up with an accuracy of 46.7% and 33.4%, respectively.Conclusion:The diagnostic performance of the CS and DP are acceptable and can be considered as useful adjunct tools in the clinical evaluation and monitoring the changes in enamel due to lesion progression under fissure sealants. However, in the clinical setting, sensitivity and specificity of these devices may be influenced by the sealant type, thickness, retention, and the differences in the lesion characteristics over time.

Hybrid Filtering Techniques For Medical Image Denoising

Acquiring images with high resolution and noise free image is a fundamental prerequisite in the handling of therapeutic picture. Nearness of commotion can prompt different misdirecting brings about the method for appropriate visual examination to separate data. Even though various noises are corrupting medical image but speckle noise is the major predominating noise in all type of medical image. Hence, it is essential to reduce the speckle noise up to acceptable level as it helps in the process of segmentation and machine learning. Many filters have been proposed for removing speckle clatter with their own points of interest and detriments for different capacities and purposes. The proposed strategies are explicitly in context of diminishing the speckle clamour in ultrasound therapeutic pictures by utilizing hybrid purifying procedures. The projected hybrid filtering techniques combines the best part of high performing filters to obtain an image with less density speckle noise while also preserving fine details, edges and textures. Hybrid filters makes use of individual filter properties and gives the best possible results. The results justify the claim and gives the cost-effective solution. The outline of the paper is to make sustainable model that increases the awareness in medical domain. It will help to reduce the frequent check-ups that indirectly gives the monetary benefit to the society.

Exploring visual soil evaluation and examination methods on highly-weathered tropical soil

National and international initiatives have been undertaken in Uganda to improve soil quality and increase crop production. However, means to evaluate and examine soil quality, particularly soil physical quality, is lacking in the country. In this study, visual soil evaluation and examination (VSEE) spade and core tests, which comprise rapid and simple methods to semi-quantitatively assess soil structure, have been tested. The derived soil quality scores Sq were compared with soil quality indicators SQi derived from traditional lab-based methods of soil structure analysis. Tests were conducted and samples taken in Uganda on highly-weathered soils with sandy clay loam texture. Both the 0–15 cm topsoil and the 15–30 cm moderately compacted subsoil were considered. Test and sampling sites comprised 18 farmers’ fields (maize, Zea mays L.) that were under conventional tillage, permanent planting basins and rip lines for three years, as well as four locations in a natural forest. All VSEE approaches tested showed a significantly better Sq score in the natural forest (good quality) as compared to maize fields (fair/moderate quality), with the subsoil always showing lower quality than the topsoil. Methods based on Visual Evaluation of Soil Structure (VESS) were more responsive to differences in soil quality than the Visual Soil Assessment (VSA) approach. Statistical analysis showed that there was a good to moderate correlation between the VSEE-based Sq scores and lab-derived SQi values, with Pearson r correlation coefficients of 0.52–0.69 for bulk density, 0.66-0.78 for air capacity, 0.53–0.73 for air permeability, 0.52–0.72 for hydraulic conductivity, 0.18-0.48 for mean weight diameter under fast wetting. The correlation with an overall integrated index of soil quality SQI ranged between 0.56 and 0.77. Minimizing the potential effect of local variability by averaging Sq scores and SQi or SQI values per treatment and depth, improved the correlation, with e.g., Pearson r ranging from 0.84 to 0.95 when relating Sq to SQI. We also found a significant correlation between VESS Sq scores and the shape of the water retention curve, particularly in the wet range (r > 0.50). Our results show that in general, VSEE methods are promising alternatives to evaluate differences in physical soil quality of highly-weathered soils in a rapid, intuitive, practical and cheap way.

Effects of thermal aging on cellulose pressboard using terahertz time-domain spectroscopy

We demonstrate a method for examining the effects of thermal aging of cellulose pressboard using terahertz time-domain spectroscopy. The change of refractive indexes at the frequencies of pulsed terahertz waves while applying heat reveals that the degree of thermal aging and the condition of thermal breakdown can be clearly analyzed by performing terahertz measurements. The visual examination method only allows evaluation of the degree of blackness on the external surfaces of cellulose pressboard. However, using terahertz techniques for non-destructive inspection enables determination of the dielectric integrity to check the strength of the electrical insulation inside the cellulose pressboard. The results indicate that the terahertz techniques could be very useful, especially in the electric power industry, which requires a variety of methods for internal non-destructive testing to ensure the safety and reliability of insulation materials in electric power facilities and components.