Simple Classification System Research Articles

Simplified PADUA Renal (SPARE) Nephrometry Scoring System: External Validation, Interobserver Variability, and Comparison with RENAL and PADUA in a Single-center Robotic Partial Nephrectomy Series

BackgroundThe RENAL (radius [R], exophytic/endophytic [E], nearness to collecting system/sinus [N], anterior/posterior [A], and location relative to polar lines [L]) and the PADUA (preoperative aspects and dimensions used for an anatomical classification) scores help in quantifying tumor complexity. However, nephrometry scoring systems have low interobserver variability. To simplify and improve score reproducibility, a new Simplified PADUA Renal (SPARE) scoring system was introduced. ObjectiveTo externally validate the SPARE nephrometry scoring system and to determine its interobserver variability. Design, setting, and participantsA total of 202 patients were included in the analysis. We performed a retrospective analysis of robot-assisted partial nephrectomy (RAPN) cases for a single renal mass performed at a single academic institution during the period 2008–2018. For each renal mass, PADUA, RENAL, and SPARE nephrometry scores were calculated. Outcome measurements and statistical analysisThree urology residents (URs), two urology attendings (UAs), two radiology residents (RRs), and one radiology attending (RA) retrospectively reviewed computed tomography scans blinded to clinical outcomes. The accuracy of the SPARE nephrometry score in the prediction of any complication (Clavien grade ≥1) was compared with other scoring systems in a univariable and a multivariate fashion. The area under the curve (AUC) and kappa statistics were used to assess interobserver variability of the SPARE score. Results and limitationsThe SPARE score was not inferior to the PADUA and RENAL scores (AUC 0.61, 0.59, and 0.57, respectively, p = 0.43). Patients with intermediate to high SPARE scores had longer operative time (158 vs 135 min, p = 0.10) and a higher rate of complications (28% vs 14%, p = 0.012). Univariable analysis predicting overall complications showed that RRs performed slightly better than URs and UAs using the SPARE score. Interobserver agreement was 84% between an RA and an RR (kappa 0.42), 85% between an RA and a UA (kappa 0.39), and 85% between an RA and a UR (kappa 0.45). ConclusionsThese findings confirm that the SPARE nephrometry scoring system is a reproducible and easy tool offering overall fair interobserver agreement regardless of years of training or type of practice, while maintaining the predictive capabilities of more established nephrometry scores. Patient summaryIn this study, a novel and simple classification system was assessed using a sample of cases from our institution to define surgical complexity renal masses detected on radiological imaging. Our findings suggest that this tool can be useful in clinical practice to facilitate the characterization of renal masses and predict the complications of surgical treatment.

150 shades of green: Using the full spectrum of remote sensing reflectance to elucidate color shifts in the ocean

This article proposes a simple and intuitive classification system by which to define full spectral remote sensing reflectance (Rrs(λ)) data with a quantitative output that enables a more manageable handling of spectral information for aquatic science applications. The weighted harmonic mean of the Rrs(λ) wavelengths outputs an Apparent Visible Wavelength (in units of nanometers), representing a one-dimensional geophysical metric of color that is inherently correlated to spectral shape. This dimensionality reduction of spectral information combined with the output along a continuum of wavelength values offers a robust and user-friendly means to describe and analyze spectral Rrs(λ) in terms of spatial and temporal trends and variability. The uncertainty in the algorithm's estimation of spectral shape is demonstrated on a global scale, in addition to the utility of the algorithm to discern spectral-spatial-temporal trends in the ocean, on a per-pixel basis for the entire 22 year continuous ocean color (SeaWiFS and MODIS-Aqua) time-series. This technique can be applied to datasets of varying multi- and hyper-spectral resolutions, providing continuity between heritage and future satellite sensors, and further enabling an effective means of elucidating similarities or differences in complex spectral signatures within the constraints of two dimensions. This straightforward means of conceptualizing multi-dimensional variability can help maximize the potential of the spectral information embedded in remote sensing data.

An Updated Classification System and Review of the Lipooligosaccharide Biosynthesis Gene Locus in Campylobacter jejuni.

Lipooligosaccharide (LOS) is an integral component of the Campylobacter cell membrane with a structure of core oligosaccharides forming inner and outer core regions and a lipid A moiety. The gene content of the LOS core biosynthesis cluster exhibits extensive sequence variation, which leads to the production of variable cell surface LOS structures in Campylobacter. Some LOS outer core molecules in Campylobacter jejuni are molecular mimics of host structures (such as neuronal gangliosides) and are thought to trigger neuronal disorders (particularly Guillain–Barré syndrome and Miller Fisher syndrome) in humans. The extensive genetic variation in the LOS biosynthesis gene cluster, a majority of which occurs in the LOS outer core biosynthesis gene content present between lgtF and waaV, has led to the development of a classification system with 23 classes (A–W) and four groups (1–4) for the C. jejuni LOS region. This review presents an updated and simplified classification system for LOS typing alongside an overview of the frequency of C. jejuni LOS biosynthesis genotypes and structures in various C. jejuni populations.

Current concepts and outcomes in cemented femoral stem design and cementation techniques: the argument for a new classification system.

Cemented implant fixation design principles have evolved since the 1950s, and various femoral stem designs are currently in use to provide a stable construct between the implant–cement and cement–bone interfaces.Cemented stems have classically been classified into two broad categories: taper slip or force closed, and composite beams or shaped closed designs. While these simplifications are acceptable general categories, there are other important surgical details that need to be taken into consideration such as different broaching techniques, cementing techniques and mantle thickness.With the evolution of cemented implants, the introduction of newer implants which have hybrid properties, and the use of different broaching techniques, the classification of a very heterogenous group of implants into simple binary categories becomes increasingly difficult. A more comprehensive classification system would aid in comparison of results and better understanding of the implants’ biomechanics.We review these differing stem designs, their respective cementing techniques and geometries. We then propose a simple four-part classification system and summarize the long-term outcomes and international registry data for each respective type of cemented prosthesis.Cite this article: EFORT Open Rev 2020;5:241-252. DOI: 10.1302/2058-5241.5.190034

Mapping the Product Range of Interdental Brushes: Sizes, Shapes, and Forces.

Preventive dentistry aims to improve oral hygiene, including the use of interdental cleansing aids. Clear and simple classifications may positively impact patient communication and motivate oral health behaviour. To date, there is no comparative analysis of interdental brush classifications and sizes. A total of 2320 interdental brush samples by 24 manufacturers was examined regarding their passage hole diameter (PHD) according to the ISO standard for interdental brushes (ISO16409:2016), and their current classifications were evaluated. Inter- and intrarater reliability of the ISO size classification were determined based on 20 raters and 10 interdental brushes. The insertion force for these interdental brushes was analysed in vitro. Excellent intra- and interrater reliability was achieved (intraclass correlation coefficient (ICC) ≥ 0.973) overall, although greater variance was observed for bigger brush sizes. Insertion forces varied depending on size and form of the brushes, amounting to 1.58 N (SD = 1.27 N) for cylindric and tapered brushes, and to 2.31 N (SD = 0.81 N) for waist-shaped brushes. The size range of commercially available products was 0.6-5.2 mm PHD, 90% presenting with a PHD ≤ 2.0 mm. Size intervals were unsystematic. The ISO size was indicated by 33% of all manufacturers, the exact PHD by 25%. The determination of the PHD is a reproducible instrument for most brushes currently on the market. In vitro, forces developed based on this classification are mostly moderate, thus unlikely to cause periodontal trauma. Given the discontinuous range and unclear labelling of available products, the development of a simplified classification system by usage of the PHD may benefit the practitioner and patient alike by contributing to improve oral hygiene behaviours.

A novel MRI-based classification of spinal cord shape and CSF presence at the curve apex to assess risk of intraoperative neuromonitoring data loss with thoracic spinal deformity correction.

Retrospective cohort. We present a simple classification system that is able to identify patients with increased odds of losing intraoperative neuromonitoring data during thoracic deformity correction. Type 3 spinal cords, with the cord deformed against the concave pedicle in the axial plane, have ×28 greater odds of losing monitoring data during surgery. Assess preoperative morphology of the spinal cord across the thoracic concavity to predict intraoperative loss of neuromonitoring data. 128 consecutive patients undergoing surgical correction of a thoracic deformity with pedicle screw/rod constructs were included. Spinal cords were classified into 3 types based on the appearance of the cord on the axial-T2 MRI at the apex of the curve. Type 1 is defined as a circular/symmetric cord with visible CSF between the cord and the apical concave pedicle/vertebral body. Type 2 is a circular/oval/symmetric cord with no visible CSF between the concave pedicle and the cord. Type 3 is a spinal cord that is flattened/deformed by the apical concave pedicle or vertebral body, with no intervening CSF (Fig.1). 128 patients were reviewed: 81 (63%) Type 1; 32 (25%) Type 2; and 12 (11.7%) Type 3 spinal cords. Lower extremity trans-cranial motor-evoked Potentials (MEPs) and/or somatosensory evoked potentials (SSEPs) were lost intraoperatively in 21 (16%) cases, with full recovery of data in 20 of those cases. On regression analysis, a Type 1 cord was protective against intraoperative data loss (OR = 0.17, p = 0.0003). Type 2 cords had no association with data loss (OR = 0.66, p = 0.49). Type 3 cords had significantly higher odds of intraoperative data loss (OR = 28.3, p < 0.0001). We present a new spinal cord risk classification scheme to identify patients with increased odds of losing spinal cord monitoring data with thoracic deformity correction. The odds of losing intraoperative MEPs/SSEPs are greater in type 3 spinal cords. III.

Classification and Staging of Morgellons Disease: Lessons from Syphilis.

IntroductionMorgellons disease (MD) is a contested dermopathy that is associated with Borrelia spirochetal infection. A simple classification system was previously established to help validate the disease based on clinical features (classes I-IV).MethodsDrawing on historical and pathological parallels with syphilis, we formulated a more detailed staging system based on clinical features as well as severity of skin lesions and corresponding histopathological infection patterns, as determined by anti-Borrelia immunohistochemical staining.ResultsClinical classes I-IV of MD are further categorized as mild, moderate and severe, or stages A, B and C, respectively, based on histopathological findings. Stage A lesions demonstrated little or no immune infiltrates and little or no disorganization of cells; macrophages were not present, and hemorrhage was negligible. Extracellular isolated spirochetes and intracellular staining of keratinocytes in the lower epidermis was occasionally seen. Stage C lesions demonstrated positive staining of keratinocytes in the stratum basale and stratum spinosum and positive intracellular staining of macrophages for Borrelia. Aggregate Borrelia colonies were frequently encountered, hemorrhage was frequent, and intracellularly stained fibroblasts were occasionally seen. Stage B lesions demonstrated a pattern intermediate between Stages A and C.ConclusionThe enhanced staging system provides objective criteria to assess the severity of dermopathy in MD. Further studies are needed to determine the optimal treatment for MD based on this staging system related to Borrelia infection.

Abstract WP260: The Left Atrial Appendage Morphology Improves Prediction of Appendage Stagnant Flow and Stroke Risk in Patients With Atrial Fibrillation Using a Simple Classification System

Background and Purpose: Previously we proposed a simple classification system of the left atrial appendage (LAA) morphology, with low risk (LAA-L) defined as one lobe with an acute angle bend arising from the proximal or middle portion and high risk (LAA-H) defined as all other morphologies. We aim to determine the association between LAA morphology (using both classification systems), LAA flow velocity, and stroke rates. Methods: We analyzed consecutive patients with atrial fibrillation (AF) selected for ablation who underwent cardiac CT angiography and transesophageal echocardiogram. The primary correlates were LAA-H and non-chicken wing (NCW) LAA morphology. The primary outcome was the composite endpoint of history of ischemic stroke/TIA or non-lacunar infarct on neuroimaging. Adjusting for CHADS2Vasc score, multivariable models were used to determine associations between LAA morphology and composite outcomes. Results: We identified 379 patients; the primary endpoint occurred in 32/379 patients (8.4%). LAA-H (adjusted OR 3.63, 95% CI 1.44-9.14) and NCW LAA morphology (adjusted OR 2.52, 95% CI 1.15-5.53) were associated with the primary endpoint. LAA flow velocity ≤20 cm/s was more common in LAA-H vs. LAA-L (9.6% vs. 2.8%, p = 0.019), but not in NCW vs. CW LAA morphology (9.7% vs. 3.7%, p = 0.054). Conclusion: The LAA H/L morphological classification system may be superior to the current system in risk stratifying patients with AF and correlates better with impaired LAA flow dynamics.

Classification of Mouth Corners in Asian Women.

Background:There is increasing interest in mouth corner lift (MCL), as well as lip augmentation. Procedures for lip corner lifting to create smiling lips include botulinum toxin, injectable filler, and surgery. However, there is no proper system to classify mouth corners, thereby causing difficulties in patient counseling, treatment planning, and communicating with medical staff. We developed a new classification system to analyze the shape of mouth corners in Asian women.Methods:Lip shapes were classified as types I (arched upper lip) and II (flat upper lip), each of which was further classified as subtypes a (upturned mouth corner) and b (flat or downturned mouth corner). Atypical cases were classified as type III. The anterior–posterior view of facial photographs were taken of female patients aged 20–40 years who visited HB Plastic Surgery Clinic between January 2017 and December 2018. Patients who visited for surgery other than lip plastic surgery (group A) and those who visited for MCL (group B) were compared. Changes in mouth corner type across age were examined.Results:The most common type was IIb in group A and Ib in group B. IIa and IIb were more common in group A, whereas Ib was more common in group B, at a statistically significant level. With increasing age, the proportions of IIb and III tended to increase, and Ia and IIa tended to decrease.Conclusion:This relatively simple classification system for mouth corners might be helpful in patient counseling and communication with medical staff during plastic surgery.

The developmental progression of English vowel systems, 1500–1800: Evidence from grammarians

This paper suggests that all Early Modern English dialects may be fitted into a simple system of classification (types A through D) based upon the relative heights of their long front vowels. Research into this period has always focused more on the trajectories of individual phonemes than on how those phonemes might have fitted together at any given time. It is argued here that changes throughout the vowel space typically occurred in bundles, and that these bundles of changes manifested themselves into discrete sequential stages. The number of vowel systems consistent with the evidence is really very small. Relying mostly on primary sources and summaries of primary sources, I classify for the first time dozens of English and foreign grammarians and turn them into witnesses for the specific stages above. Selected grammarians’ Continental vowel symbols (a wholly neglected resource) are diagrammed into clear phonetic snapshots of each stage. These symbols also illuminate trajectories. For example, while the proto-IPA phonetic alphabets of certain English grammarians show FACE raising from Continental <a> to <é>, French grammarians’ symbols actually specify the steps: from “almost” <ê> to <ai> to <é> ([æ:, ɛ:, e:]). Dates for these changes are noted with unusual care. All in all, the facts and views advanced here support the traditional timeline established for the major sound changes, although many fresh details are added, including evidence for an unreported phase in the late 1500s in which ME /ai/ was fully distinct as /ɛ:/ in popular London English. Fresh evidence is also produced about the dissolution of the MEAT phoneme, the origins of THOUGHT monophthonging, and the development of START–BATH and NORTH–CLOTH lengthening.

Reliability of meniscus tear description: a study using MRI from the Osteoarthritis Initiative.

Despite being one of the most common indications for surgery, data on the types of meniscus tear that should be treated surgically are limited. Improving patient selection requires agreement on meniscus tear description. This study evaluates a simple MRI tear classification system for inter-observer agreement. Knee MRI examinations from 57 subjects from the Osteoarthritis Initiative cohort were reviewed by two sub-specialty trained, musculoskeletal radiologists. Based on two pulse sequences, each meniscus was classified by: tear or no tear; location of tear in anterior, middle or posterior third or multiple thirds; and displaced or non-displaced radial, horizontal, longitudinal or complex tear pattern. A tear was defined as signal abnormality extending to the surface on at least two images and displacement as more than 2mm of extrusion or separation measured orthogonal to the tear plane. Kappa, weighted Kappa and percentage agreement were calculated. For the medial meniscus, Kappa and percentage agreement estimates were, respectively: the presence of tear, 0.79 and 89.5%; tear with displacement, 0.70 (weighted Kappa) and 66.0%; tear description, 0.47 and 61.4%; tear location, 0.64 and 79.0%. For the lateral meniscus, estimates were: the presence of tear, 0.75 and 89.5%; tear with displacement, 0.81 (weighted Kappa) and 86.0%; tear description, 0.56 and 78.9%; tear location, 0.74 and 87.7%. The strength of agreement between readers was moderate to substantial underscoring the challenge of meniscus tear classification.

Congenital Maxillomandibular Syngnathia: Review of Literature and Proposed New Classification System.

Maxillomandibular fusion (syngnathia) is a rare craniofacial anomaly. It occurs as either fibrous (synechiae) or bony (synostosis) fusion of jaw or fusion of mandible to zygoma, tuberosity, hard palate and temporal bone. There are several documentations delineating this condition but owing to its varying presentation, association with both intraoral and extraoral anomalies and syndromes, reviewing it has been as uphill task. The non-unanimous description of cases in the literature and the use of different nomenclatures make it difficult to classify this condition. Extensive search of the literature was done from the year 1936 to 2018 which included a total of 118 cases with 62 cases of bony fusion, 48 cases of fibrous fusion and 8 cases of combined fusion, i.e., fibrous on one site and bony on another side. This paper proposes a novel, simple and explicit classification system on the basis of nature of fusing tissues, location and extent, association with syndrome after reviewing the existing literature. Furthermore, this review reports 4 new cases of syngnathia along with their clinical, radiographic features and their management protocol. This classification can be generalized to all the cases of syngnathia and can further facilitate in its appropriate diagnosis and treatment plan.

Etiology-Based Classification of Adjacent Segment Disease Following Lumbar Spine Fusion.

Adjacent segment disease (ASDz) is a potential complication following lumbar spinal fusion. A common nomenclature based on etiology and ASDz type does not exist and is needed to assist with clinical prognostication, decision making, and management. The objective of this study was to develop an etiology-based classification system for ASDz following lumbar fusion. We conducted a retrospective chart review of 65 consecutive patients who had undergone both a lumbar fusion performed by a single surgeon and a subsequent procedure for ASDz. We established an etiology-based classification system for lumbar ASDz with the following six categories: "degenerative" (degenerative disc disease or spondylosis), "neurologic" (disc herniation, stenosis), "instability" (spondylolisthesis, rotatory subluxation), "deformity" (scoliosis, kyphosis), "complex" (fracture, infection), or "combined." Based on this scheme, we determined the rate of ASDz in each etiologic category. Of the 65 patients, 27 (41.5%) underwent surgery for neurogenic claudication or radiculopathy for adjacent-level stenosis or disc herniation and were classified as "neurologic." Ten patients (15.4%) had progressive degenerative disc pathology at the adjacent level and were classified as "degenerative." Ten patients (15.4%) had spondylolisthesis or instability and were classified as "instability," and three patients (4.6%) required revision surgery for adjacent-level kyphosis or scoliosis and were classified as "deformity." Fifteen patients (23.1%) had multiple diagnoses that included a combination of categories and were classified as "combined." This is the first study to propose an etiology-based classification scheme of ASDz following lumbar spine fusion. This simple classification system may allow for the grouping and standardization of patients with similar pathologies and thus for more specific pre-operative diagnoses, personalized treatments, and improved outcome analyses.

New insight to the characteristics and clinical course of clusters of patients with imaging confirmed disc-related sciatica.

Referral to secondary care is common for a considerable proportion of patients with persistent sciatica symptoms. It is unclear if information from clinical assessment can further identify distinct subgroups of disc-related sciatica, with perhaps different clinical courses. This study aims to identify and describe clusters of imaging confirmed disc-related sciatica patients using latent class analysis, and compare their clinical course. The study population were 466 patients with disc-related sciatica. Variables from clinical assessment were included in the analysis. Characteristics of the identified clusters were described and their clinical course over 2 years was compared. A four-cluster solution was optimal. Cluster 1 (n=110) had mild back and leg pain; cluster 2 (n=59) had moderate back and leg pain; cluster 3 (n=158) had mild back pain and severe leg pain; cluster 4 (n=139) had severe back and leg pain. Patients in cluster 4 had the most severe profile in terms of disability, distress and comorbidity and the lowest reported global change and the smallest proportion of patients with a successful outcome at 2 years. Of the 135 patients who underwent surgery, 42% and 41% were in clusters 3 and 4, respectively. Using a strict diagnosis of sciatica, this work identified four clusters of patients primarily differentiated by back and leg pain severity. Patients with severe back and leg pain had the mostsevereprofileat baseline and follow-upirrespective of intervention. This simple classification systemmay be useful when considering prognosis and management with sciatica patients. Using data from a large observational prospective study, this work identifies four distinct clusters of patients with imaging confirmed disc-related sciatica. This classification could be used when considering prognosis and management with sciatica patients at their initial consultation.

Automated objective and marker-free facial grading using photographs of patients with facial palsy.

An automated, objective, fast and simple classification system for the grading of facial palsy (FP) is lacking. An observational single center study was performed. 4572 photographs of 233 patients with unilateral peripheral FP were subjectively rated and automatically analyzed applying a machine learning approach including Supervised Descent Method. This allowed an automated grading of all photographs according to House-Brackmann grading scale (HB), Sunnybrook grading system (SB), and Stennert index (SI). Median time to first assessment was 6days after onset. At first examination, the median objective HB, total SB, and total SI were grade 3, 45, and 5, respectively. The best correlation between subjective and objective grading was seen for SB and SI movement score (r = 0.746; r = 0.732, respectively). No agreement was found between subjective and objective HB grading [Test for symmetry 80.61, df=15, p < 0.001, weighted kappa = - 0.0105; 95% confidence interval (CI) = - 0.0542 to 0.0331; p = 0.6541]. Also no agreement was found between subjective and objective total SI (test for symmetry 166.37, df =55, p < 0.001) although there was a nonzero weighted kappa = 0.2670; CI 0.2154-0.3186; p < 0.0001). Based on a multinomial logistic regression the probability for higher scores was higher for subjective compared to objective SI (OR 1.608; CI 1.202-2.150; p = 0.0014). The best agreement was seen between subjective and objective SB (ICC = 0.34645). Automated Sunnybrook grading delivered with fair agreement fast and objective global and regional data on facial motor function for use in clinical routine and clinical trials.

Outcomes of a simplified mosaic ranking system

Investigating outcomes of transferring mosaic embryos according to a simplified classification system that replaced our more complex 1-9 ranking system. Following previous implementation of a comprehensive mosaicism classification system, a review of our mosaic embryo outcome data, together with that of recent literature (Spinella et al 2018, and Munne et al 2017) was conducted. The goal was to introduce a more simplified classification system – using an A-D grading – which ranks mosaic embryos for clinical use (as per table below). The study included 158 single transfers of embryos (between April 2016 to February 2019) which exhibited a mosaic shift (ranging from 20-79%) using NGS technology. TF-A = NAD (no abnormality detected) – first choice for transfer TF-B = Noisy result/low level mosaicism <=40% – second choice TF-C: MOSAIC (significant mosaicism detected >40-< 80%) -third choice, further stratified by: C1: -segmental -low risk chromosomes C2: -high risk chromosomes TF-D: ABN (abnormal) – not available for transfer Mosaic embryos were separated into the above categories dependent on the percentage of mosaicism present in the sample and the chromosome involved, with only levels over 40% being reportable findings. This study retrospectively compared the positive bHCG and fetal heart (FH) outcomes for the TF-A, B and C groups. We also analyzed outcomes for whole chromosome mosaics compared to segmental mosaic findings. We found that overall, TF-A group had the highest positive bHCG rates (62.9%) and FH rates (53.7%) followed by TF-B bHCG (57.6%) and FH rates (47.6%). TF-C had lower positive bHCG rates outcomes (44%) and FH rates (36%). Analysing TF-C (40-80% mosaics) in more detail we found that segmentals had higher bHCG and FH rates (69.2% and 61.5%) compared to whole chromosome mosaics (20% and 10%). Furthermore, irrespective of the mosaic percentage, all single segmentals (in the 20-80% range) had clearly better outcomes than multiple segmentals (bHCG; 63.3% vs 44.4% and FH; 48.3% vs 33.3%). In comparison low level segmental mosaics (<=40%) had higher bHCG (58.9%) and FH (42.9%) rates compared to low level whole chromosome mosaics (44.8%) and (36.2%). Overall the positive bHCG and fetal heart outcomes support the simplified classification system and the concept of preferentially transferring low level before high level whole chromosome mosaics in the absence of NAD embryos. Single segmental mosaic embryos have improved clinical outcomes compared to whole chromosome mosaic embryos and should be considered for preferential transfer ahead of other types of mosaic findings. Whole chromosome mosaics should be considered last choice.

Development of Failure Cause–Impact–Duration (CID) Plots for Water Supply and Distribution System Management

Understanding the impact and duration (consequences) of different component failures (cause) in a water supply and distribution system (WSDS) is a critical task for water utilities to develop effective preparation and response plans. During the last three decades, few efforts have been devoted to developing a visualization tool to display the relationship between the failure cause and its consequences. This study proposes two visualization methods to effectively show the relationship between the two failure entities: A failure cause–impact–duration (CID) plot, and a bubble plot. The former is drawn for an effective snapshot on the range (extent) of failure duration and the impact of different failures, whereas the latter provides failure frequency information. A simple and practical failure classification system is also introduced for producing the two proposed plots effectively. To verify the visualization schemes, we collected records of 331 WSDS component failures that occurred in South Korea between 1980 and 2018. Results showed that (1) the proposed CID plot can serve as a useful tool for identifying most minor and major WSDS failures, and (2) the proposed bubble plot is useful for determining significant component failures with respect to their failure consequences and occurrence likelihoods.

A simple classification of peritoneal contamination in perforated appendicitis predicts surgery-related complications.

Perforated appendicitis has poorer clinical outcomes compared to non-perforated appendicitis. However, accurate outcome comparisons in research and clinical audits are challenged by its wide spectrum of manifestation. Previous attempts at the classification of severity have been complex and difficult to reproduce. In our study, we used another institution's (Jones et al., TX, USA) previously described simple classification system of peritoneal contamination and examined its usefulness in predicting outcomes. With ethical approval, we retrospectively reviewed the records of all paediatric patients operated at our institution for perforated appendicitis from 2016 to 2017. Patient demographics, intra-operative and histological findings, post-operative outcomes and length of stay were collected. Patients were categorised into group 1 (purulence in right lower quadrant only) and group 2 (contamination in two or more quadrants). Post-operative complications were defined as procedure-related (e.g. post-operative ileus, intra-abdominal abscess, visceral injury) and non-procedure-related (e.g. bronchospasm). Statistical analysis using χ2 tests for categorical data and Mann-Whitney U-tests for non-parametric continuous variables was performed, with a significance of P < 0.05. There were 134 eligible patients. We excluded 19 with incomplete data, leaving 115 for analysis, of which 69 (60%) were in group 2. Those in group 2 had a longer stay (P = 0.005) and more post-operative complications (P = 0.001), particularly procedure-related events (P = 0.006). There were no differences in age (P = 0.182), gender (P = 0.876), readmission rate (P = 0.317) and non-procedure-related post-operative complications (0.152). This simple classification of perforated appendicitis appears to differentiate clinical outcomes well, particularly for iatrogenic morbidity, making it useful for operative preparation and outcomes research.

Supervised classification of landforms in Arctic mountains

AbstractErosional and sediment fluxes from Arctic mountains are lower than for temperate mountain ranges due to the influence of permafrost on geomorphic processes. As permafrost extent declines in Arctic mountains, the spatial distribution of geomorphic processes and rates will change. Improved access to high‐quality remotely sensed topographic data in the Arctic provides an opportunity to develop our understanding of the spatial distribution of Arctic geomorphological processes and landforms. Utilizing newly available Arctic digital topography data, we have developed a method for geomorphic mapping using a pixel‐based linear discriminant analysis method that could be applied across Arctic mountains. We trained our classifier using landforms within the Adventdalen catchment in Svalbard and applied it to two adjacent catchments and one in Alaska. Slope gradient, elevation–relief ratio and landscape roughness distinguish landforms to a first order with &gt;80% accuracy. Our simple classification system has a similar overall accuracy when compared across our field sites. The simplicity and robustness of our classification suggest that it is possible to use it to understand the distribution of Arctic mountain landforms using extant digital topography data and without specialized classifications. Our preliminary assessments of the distribution of geomorphic processes within these catchments demonstrate the importance of post‐glacial hillslope processes in governing sediment movement in Arctic mountains.

Acute lens opacity induced by different kinds of anesthetic drugs in mice.

To study whether specific anesthetic drugs or tear layer evaporation was primarily responsible for the acute cataract and what the change of lens structure is in anesthetized mice. Five groups were set up in the experiment: Group A (topicamide and phenylephrine mixed eye drop+ chloral hydrate), Group B (tropicamide and phenylephrine mixed eye drop+sevoflurane), Group C (tropicamide and phenylephrine mixed eye drop), Group D (topicamide and phenylephrine mixed eye drop+chloral hydrate, carbomer eye drop in the right eyes), and Group E (tropicamide and phenylephrine mixed eye drop+sevoflurane, carbomer eye drop in the right eyes). A simple classification system was used to assess the severity of lens opacity. And a numerical value from 0 to 3 to each grade was assigned for the cataract index calculation and data analysis. The gross appearance and time course of development of lens opacity were assessed. Hematoxylin and eosin staining was used to observe the lens structure changes in the reversible cataract. Tropicamide did not induce lens opacification in mice. Lens opacity caused by inhaled sevoflurane was similar to injected cholral hydrate. Both inhaled-anesthetic-induced lens opacity and injected-anesthetic-induced lens opacity could be prevented by carbomer eye drop. In the severe opacity lens, a wide range of lens fiber cell structure had disordered. The fiber cells became uneven thickness. The acute reversible lens opacity can unilaterally develop or be induced by a local cause. The structure of lens fiber cells changed in the lens opacity which may influence the permanent connection of the lens fiber cells. This study was not only of practical significance to help maintain lens transparency for eye research, but also of the deeper consideration about the reversible lens opacification phenomenon.