Morphological Types Research Articles

EPCO-31. THE GERMLINE POLYMORPHISM RS55705857 IS ASSOCIATED WITH A POOR SURVIVAL IN ASTROCYTOMA, IDH-MUTANT, GRADE 2

Abstract Histologic features, presence of CDKN2A/B homozygous deletion and methylation subtype are strong determinants of outcome and of therapy in IDH-mutant gliomas. We were interested in learning if there are additional markers of outcome in these tumors. To address this question, we assembled a cohort of 963 IDH-mutant gliomas with overall survival data (median follow-up alive 2.7 years, median follow-up deceased 3.9 years). Array-based copy number data, targeted NGS, germline genotyping data and Illumina EPIC array methylation data were available on 872, 226, 542, and 401 patients, respectively. Morphologic type (oligodendroglioma versus astrocytoma, grade (2/3 vs 4) and methylation subtype (A_IDH_LG vs A_IDH_HG) were all significantly associated with survival (p <0.001). There was no significant difference in survival between grade 2 vs 3 IDH-mutant astrocytomas (p=0.53 adjusting for age and sex). However, subjects with the risk allele (G) for rs55705857 had a better overall survival than subjects with the non-risk allele (A) in IDH-mutant oligodendroglioma (AG/GG vs AA, median overall survival 21.6 vs 15.7 years, p=0.048 after adjusting for grade, age, and sex). Conversely, rs55705857 was associated with a markedly worse survival in grade 2 IDH-mutant astrocytomas (AG/GG vs AA, median overall survival 8.6 vs 19.6 years, p=0.007 after adjusting for age and sex). Despite similar sample sizes and number of deaths, there was no significant difference in overall survival by rs55705857 genotype in grade 3 or 4 IDH-mutant astrocytomas. Upon further functional analyses, TLX1 and GALNT17 were found to be differentially methylated in IDH1-mutant astrocytomas and oligodendrogliomas, respectively, when stratified by rs55705857 risk allele. This is the first observation of a germline characteristic (e.g. rs55705857) predicting survival in low-grade IDH-mutant astrocytoma. While this observation requires validation, it suggests that germline genotype may be practice changing and inform results of trials such as CATNON and CODEL.

Histological Subtypes Might Help Risk Stratification in Different Morphological Types of IPMNs: Back to the Future?

Background: Intraductal papillary mucinous neoplasms (IPMNs) display four histological subtypes: gastric foveolar, pancreaticobiliary, intestinal, and oncocytic. All of these subtypes harbor a different risk of cancer development. The clinical impact of these subtypes concerning the occurrence of high-grade dysplasia (HGD)/cancer (C) in specific morphological types, such as branch-duct (BD), main-duct (MD), and mixed-type (MT) IPMNs, has been less investigated. Hence, our aim was to investigate the prevalence of histological subtypes and their possible association with HGD/C concerning morphologically different IPMNs. Methods: This was a retrospective review of demographics, risk factors, and histological features in a surgical cohort of patients having undergone resection for suspect malignant IPMNs at a high-volume tertiary center from 2007 to 2017. Results: A total of 273 patients were resected for IPMNs from during the study period, of which 188 were included in the final analysis. With sex- and age-adjusted multivariable logistic regression analysis across the entire cohort, gastric foveolar subtypes were associated with a reduced prevalence of HGD/C (OR = 0.30; 0.11–0.81, 95% CI, 95%CI; p = 0.01). With univariable logistic regression analysis, in the BD-IPMN subgroup, the pancreaticobiliary subtype was associated with an increased prevalence of HGD/C (OR = 18.50, 1.03–329.65, 95% CI; p = 0.04). In MD- and MT-IPMNs, the gastric foveolar subtype was associated with a decreased prevalence of HGD/cancer (OR = 0.30, 0.13–0.69, 95% CI; p = 0.004). Conclusions: In MD and MT-IPMNs, the gastric-foveolar subtype is associated with a lower prevalence of HGD/C, possibly identifying in such a high-risk group, a subgroup with more indolent behavior. In BD-IPMNs, the pancreaticobiliary subtype is associated with a higher prevalence of HGD/C, conversely identifying among those patients, a subgroup deserving special attention.

Manipulation in the In Situ Growth Design Parameters of Aqueous Zinc‐Based Electrodes for Batteries: The Fundamentals and Perspectives

ABSTRACTPrecise exploitation of the growth of Zn metal anode in a power converter system has re‐emerged as one of the technological interests that have surged globally in the past 5 years, specifically to improve the practical use of deep cycling metal batteries. In this review, the in situ architectures of aqueous Zn metal‐based batteries focusing on the intrinsic geometrical building block and their respective mode of assembly classifying the deposition morphologies are scrutinised and discussed. The fundamental electrochemical kinetic principles and the associated critical issues, especially associated with the metal plague deposition that influences the morphology of deposited Zn, are considered. Also, the growing interest in the interphase system, which has an intense influence in characterising the types of Zn deposition morphology, is included. Consideration of the fundamental crystal features of Zn, endowing the predominant key for its growth assembly, is provided. Last, the review offers perspectives on the current progress of Zn–Air batteries in the application of electric vehicles.

Impatiens mogangensis (Balsaminaceae), a new species from Yunnan, China

Impatiens mogangensis, a new species discovered in the limestone region of southeast Yunnan, China, is described and illustrated. Based on characteristics such as extremely contracted pedicels, connate lateral united petals, and four-locular ovary, this species is classified within Impatiens sect. Semeiocardium. Within the section, I. mogangensis resembles I. morsei morphologically in the white-tipped, yellow and brown-striated flowers, obconic capsule, and brick-shaped seeds. Additionally, I. mogangensis is similar to I. bonii in their reflexed lower lobes of lateral united petals, obconic capsules, and brick-shaped seeds, but can be distinguished from I. morsei and I. bonii by having 5–7 pairs of lateral leaf veins, serrate leaf margins, and falcate lower lobes of the lateral united petals. Besides, I. mogangensis is confined to the limestone region in Mogang village of south-eastern Yunnan and does not overlap with the distribution of I. morsei and I. bonii. In conclusion, the new species we proposed is a morphological transitional type between I. morsei and I. bonii respectively with their endemic geographical distributions.

Surgical Management of Thoracic Dorsal Arachnoid Webs: A 10-Year Single-Institution Experience

ObjectiveThoracic dorsal arachnoid webs are intradural membranes that may cause obstruction of CSF flow and spinal cord compression. While well-recognized, they are rare and there is a paucity of long-term data on their natural history and prognosis. We reviewed radiographic features, surgical indications, and pathologic specimens of patients diagnosed with focal thoracic dorsal arachnoid webs. MethodsA radiology database and surgical case logs were queried for thoracic arachnoid webs at a single hospital system for a ten-year period. A retrospective chart review was performed on identified cases. ResultsWe identified 127 patients with dorsal thoracic arachnoid webs. Arachnoid webs were radiographically classified into three morphologic types: Type 1 (54%) causing spinal cord deformity only, Type 2 (32%) producing cord deformity with myelomalacia, and Type 3 (14%) with cord deformity, myelomalacia, and syringomyelia. These arachnoid webs were commonly centered at the upper thoracic T4 segmental level. Forty-one cases (32%) required surgery, generally for thoracic myelopathy with gait instability (46%) and lower extremity numbness and pain (39%). In patients who underwent surgery, 79% experienced symptomatic improvement and 21% remained stable, after an average of 21 months follow-up evaluation. Surgical pathology revealed fibrous connective tissue (100%) with calcifications (26%) or inflammation (7%). ConclusionsThe majority in a large series of patients with dorsal arachnoid webs did not undergo surgical intervention, but those with myelomalacia and syrinx experienced radiographic and clinical deterioration without surgery. Surgery to treat symptomatic arachnoid webs results in significant clinical improvement with low surgical morbidity.

Development and Validation of an Individualized Nomogram for Predicting Patent Foramen Ovale-Associated Stroke: Patent Foramen Ovale Morphology-Based Analysis.

We previously reported four patent foramen ovale (PFO) morphological types that influenced right-to-left shunt (RLS) grades. Herein, we aimed to study the relationship between PFO morphology and cryptogenic stroke (CS). We further developed a nomogram based on four PFO morphological types and functional parameters to guide clinicians in judging the risk of PFO-associated stroke. This was a retrospective observational study involving adult patients with PFO between January 2020 and November 2022. Patients were divided into a PFO-associated stroke group (CS group) and a group without cryptogenic stroke (non-CS group). Four types of PFO and RLS grades were analyzed. Nomograms were made to predict PFO-associated stroke using multivariable logistic regression analysis. The discrimination performance of the model was internally validated and assessed using the receiver operating characteristic. We enrolled 389 patients (male, 182 patients; female, 207 patients) with PFO, the mean age was 43.3±8.1 years. The derivation cohort comprised 293 patients (CS group, 186 patients; non-CS group, 107 patients). The predictive nomogram comprised PFO morphological types, interatrial septum (IAS) mobility distance, septum primum thickness, PFO channel length at rest, and contrast-transthoracic echocardiography (c-TTE) RLS grade during the Valsalva maneuver. A validation cohort was established (CS group, 61 patients; non-CS group, 35 patients). The model area under the curve (AUC) was 0.891 (95% confidence interval = 0.855-0.928) in the derivation cohort and 0.935 (95% confidence interval = 0.885-0.986) in the validation cohort. Calibration curve analysis showed that the nomogram had a C-index of 0.891 in the derivation cohort and 0.935 in the validation cohort. The decision curve analysis (DCA) indicated that the nomogram had clinical applicability. Adding four PFO morphological types improved the risk stratification capability for PFO-associated stroke. The nomogram can identify high or low-risk PFO individuals and select patients who will likely benefit from interventional device closure.

Micronutrient status and associated factors of anemia among undernourished children of 5-18 years: First study from Himalayan foothills

ABSTRACT Purpose: Undernutrition in children is a critical worldwide concern that hampers both their physical and cognitive growth. The nutritional status of school-going children and adolescents remains insufficiently addressed with no comprehensive data. This is the first study from the Himalayan foothills that aims to assess the clinical and laboratory aspects of anemia with micronutrient status in undernourished children above the age of five along with association of clinical features with anemia severity. Materials and Methods: A cross-sectional study was conducted involving children aged 5-18 years with undernutrition in a tertiary hospital in North India over eighteen months. We observed the prevalence of anemia, its morphological type, micronutrient status, clinical features, and demographic parameters of these children. The association of various clinical features and anthropometric parameters with the severity of anemia was determined. Results: Of the 200 children who were enrolled in the study, 77% were found anemic, with the proportion of mild, moderate, and severe anemia being 18.2%, 46.8%, and 35%, respectively. Iron (67%) was the most common micronutrient deficient in these children with a significant number suffering from vitamin B12 (53.9%) deficiency. Folic acid deficiency was relatively low (10.4%). Body mass index (P = 0.009), fatigability (P = 0.001), pallor (P ≤ 0.001), poor academic performance (P = 0.023), and knuckle hyperpigmentation (P = 0.018) were significantly associated with the severity of anemia. Conclusion: Despite the significant tread in various aspects of human development, undernutrition and anemia remain a formidable challenge, especially in developing countries. A high proportion of anemia in undernutrition indicates the gravity of the issue, yet not received the deserved attention.

Morphological control for hollow rod crystals of a photochromic diarylethene on spherulites by surface properties of substrates.

Sublimation methods utilizing the surface properties of substrates can address the challenge of controlling hollow morphologies in rod crystals. Spherulites were formed on the hydrophilic surface of the (0001) planes of α-quartz and sapphire substrates by sublimation of 1,2-bis(3,5-dimethyl-2-thienyl)perfluorocyclopentene (1a). Various types of hollow morphologies, distinguished by the size and shape of their cross sections and by the presence or absence of branching structures, were formed separately on α-quartz and sapphire substrates. Such precise control of the hollow morphologies was attributed to the wettability of each substrate, leading to the formation of spherulites of 1a. In addition, it was indicated that the formation process of the surface morphologies of spherulites was associated with the hollow morphologies of rod crystals of 1a.

Amyloid-Beta, Tau, and Microglial Activation in Aged Felid Brains.

Alzheimer's disease (AD) and its associated pathology have been primarily identified in humans, who have relatively large brains and long lifespans. To expand what is known about aging and neurodegeneration across mammalian species, we characterized amyloid-beta (Aβ) and tau lesions in five species of aged felids (n = 9; cheetah, clouded leopard, African lion, serval, Siberian tiger). We performed immunohistochemistry to detect Aβ40 and Aβ42 in plaques and vessels and hyperphosphorylated tau in the temporal lobe gyrus sylvius and in the CA1 and CA3 subfields of the hippocampus. We also quantified the densities and morphological types of microglia expressing IBA1. We found that diffuse Aβ42 plaques, but not dense-core plaques, were present more frequentlyin the temporal cortex and tended to be more common thanAβ40 plaques across species. Conversely, vascular Aβ was labeled more consistently with Aβ40 for each species on average. Although all individuals showed some degree of Aβ40 and/or Aβ42 immunoreactivity, only the cheetahs and clouded leopards exhibited intraneuronal hyperphosphorylated tau (i.e., pretangles), which was more common in the hippocampus. Reactive, intermediate microglia were significantly associated with total Aβ40 vessel area and pretangle load in the hippocampus. This study demonstrates the co-occurrence of Aβ and tau pathology in two felid species, cheetahs and clouded leopards. Overall, these results provide an initial view of the manifestation of Aβ and tau pathology in aged, large-brained felids, which can be compared with markers of neurodegeneration across different taxa, including domestic cats, nonhuman primates, and humans.

Patent ductus arteriosus stenting via femoral approach with wire twist technique: a case report

IntroductionPatent ductus arteriosus (PDA) stenting has emerged as a viable alternative to surgical interventions for ductus arteriosus-dependent pulmonary circulation. Several approaches and techniques have been reported but have had limited success.We present three cases of PDA stenting involving several types of PDA morphologies using the femoral vessel approach and introduce a highly successful technique.Case presentationCase 1: A 3-day-old female with pulmonary atresia and an intact ventricular septum had two stents implanted via the femoral artery (FA) in a PDA originating from the descending aorta. A 0.014-inch coronary guidewire was secured in the peripheral pulmonary artery (PA) to aid stent tracking, achieving postoperative oxygen saturation (SpO2) of 88%.Case 2: An 11-day-old male with pulmonary atresia and ventricular septal defect (PA/VSD) had a stent implanted in a PDA arising from the inferior aspect of the aortic arch via the femoral vein (FV). Postoperative SpO2 reached 92%.Case 3: A 2-month-old female with PA/VSD received two stents via the FA in a PDA originating from the innominate artery, achieving a postoperative SpO2 of 88%.ConclusionsThe wire twist technique is useful for implanting PDA stents through the transfemoral approach.

Novel morphological classification of left atrial appendage using 3-dimensional printer -rock, paper and scissors-

Abstract Background The WATCHMAN device was developed as a permanent implantable device to seal off the LAA to prevent cardiogenic embolism. It has been used in Japan since September 2019 only for patients who are at the high risk of bleeding events. It is known that the LAA diameter of Asians is larger than that of non-Asians. Furthermore, the LAA of the Japanese are more complicated, compared to the Western. Whereas the four classifications from previous reports are widely used in the world, the classification differs with different physicians in the real-world practice. Purpose We aimed to identify the relationship between morphological features of LAA and clinical events such as ischemic stroke in Japanese patients. Methods All LAAC cases in our institution performed between February 2020 and December 2023 were retrospectively analyzed. The three-dimensional printing of LAA was generated from cardiovascular computed tomography imaging data. The shapes of the LAA were classified into 3 morphological types: (1) The LAA with bi lobe was defined as "Scissors" type; (2) The one with complicated peripheral branches was "Paper" type; (3) The simple one was "Rock" type. We examined the between the risk of cardioembolic stroke and the morphological features of the LAA. The left atrial appendage was classified by two cardiologists, and when they made different choices, we used the operator's choice. Results The cohort consisted of 116 patients, excluding 22 patients without CT scans. Of those, 30 (26%), 38 (33%) and 48 (41%) patients were divided into the Rock, Scissors and Paper types, respectively. All groups were identically matched for comorbidities. Table shows the patient characteristics and the results of univariate and multivariate analysis. There were 51 (44%) patients who had a history of cardioembolic stroke (18% vs. 30% vs. 53%; Rock vs. Scissors vs. Paper types, p-value = 0.05). In the multivariate analysis, the Paper type is the potential risk factor of cardioembolic stroke (p-value = 0.01). In addition, of those, 36 (31%), 32 (28%), 28 (24%) and 20 (17%) patients were divided into the Chicken wing, Cactus, Cauliflower and Windsock types, respectively. The four types were not associated with prior cardioembolic stroke events (18% vs. 25% vs. 55%; Chicken wing vs. Cactus vs. Cauliflower vs. Windsock types, p-value = 0.83). The match rate of cardiologists’ choice was 86.2% for the new classification and 44.8% for the classical classification. Conclusions The morphological features of LAA by three-dimensional printing was significantly related to cardioembolic stroke in this population. Patients with Paper type LAA were significantly more likely to have had a history of cardioembolic stroke. These results could have a relevant impact on the antithrombotic management of patients who are at the high risk of embolic and bleeding events and, moreover, LAAC could be the best option for these patients.

Morphological Shortening in Mobile Legend Video Game

This study aims to classify the morphological types of shortening and explain their meaning. in Mobile Legends players within online community forums. The research methodology used qualitative methods and the data collected from Facebook Groups Mobile Legend: Bang Bang Official. This research used Schendl (2001) theories about five types of morphological shortening words, they are acronym, clipping, blends, contraction, and shortening. The research reveals that shortening serves multiple purposes in the gaming environment. They are primarily used to accelerate communication, thereby enhancing the efficiency of message delivery. Additionally, shortening creates a sense of belonging among players by fostering a shared linguistic culture. This study provides valuable insights into the dynamics of language within the online gaming context and explores how these shortening influence interactions among players. By understanding the role of morphological shortening, the research sheds light on how they enhance communication efficiency and build community cohesion in gaming environments. Keywords: Morphological Shortening, Game, Mobile Legends, Online Community

Additions to the genus Kirschsteiniothelia (Dothideomycetes); Three novel species and a new host record, based on morphology and phylogeny.

During a survey of microfungi associated with forest plants, four specimens related to Kirschsteiniothelia were collected from decaying wood in Guizhou, Hainan and Yunnan Provinces, China. Kirschsteiniothelia species have sexual and asexual forms. They are commonly found as saprophytes on decaying wood and have been reported as disease-causing pathogens in humans as well. In this study, we introduce three novel Kirschsteiniothelia species (K.bulbosapicalis, K.dendryphioides and K.longirostrata) and describe a new host record for K.atra, based on morphology and multi-gene phylogenetic analyses of a concatenated ITS, LSU and SSU rDNA sequence data. These taxa produced a dendryphiopsis- or sporidesmium-like asexual morph and detailed descriptions and micromorphological illustrations are provided. Furthermore, we provide a checklist for the accepted Kirschsteiniothelia species, including detailed host information, habitat preferences, molecular data, existing morphological type, country of origin and corresponding references.

Improving Automatic Coronary Stenosis Classification Using a Hybrid Metaheuristic with Diversity Control.

This study proposes a novel Hybrid Metaheuristic with explicit diversity control, aimed at finding an optimal feature subset by thoroughly exploring the search space to prevent premature convergence. Background/Objectives: Unlike traditional evolutionary computing techniques, which only consider the best individuals in a population, the proposed strategy also considers the worst individuals under certain conditions. In consequence, feature selection frequencies tend to be more uniform, decreasing the probability of premature convergent results and local-optima solutions. Methods: An image database containing 608 images, evenly balanced between positive and negative coronary stenosis cases, was used for experiments. A total of 473 features, including intensity, texture, and morphological types, were extracted from the image bank. A Support Vector Machine was employed to classify positive and negative stenosis cases, with Accuracy and the Jaccard Coefficient used as performance metrics. Results: The proposed strategy achieved a classification rate of 0.92 for Accuracy and 0.85 for the Jaccard Coefficient, obtaining a subset of 16 features, which represents a discrimination rate of 0.97 from the 473 initial features. Conclusions: The Hybrid Metaheuristic with explicit diversity control improved the classification performance of coronary stenosis cases compared to previous literature. Based on the achieved results, the identified feature subset demonstrates potential for use in clinical practice, particularly in decision-support information systems.

Microglia and Macrophages in Human Pineal Gland

Background. The causal role of the inflammatory process in the central nervous system (CNS) in the pathogenesis of most nervous and mental diseases, as well as in aging, has been established in the last two decades. The most important immune cells in the CNS are microglial cells and macrophages. To date, microglia and macrophages have been studied in various areas of the central nervous system, but have not been studied in the human pineal gland. The purpose of the study was to investigate the morphological features, types and localization of human pineal gland microglial cells using immunohistochemistry. Material and methods. The work was carried out on samples of the human brain pineal gland aged from 16 to 61 years (n=7). An immunohistochemical reaction was performed on sections of the pineal gland using antibodies to Iba-1 and TMEM119, the selective markers of microgliocytes. The frequency of occurrence of immunostained cells was analyzed using statistical methods. Results. It has been established that the majority of phagocytic cells of the structurally normal human pineal gland are not macrophages, but microgliocytes, which are represented by both resting and activated forms. Microglia in the human pineal gland are typically localized in connective tissue trabeculae, both at and away from blood vessels. Microgliocytes are also found in the parenchyma of the pineal gland among the hormone-synthesizing pinealocytes. There was a statistically significant decrease in the number of Iba-1- and especially TMEM119-immunoreactive cells with aging. Conclusion. The present study is the first to examine microglial cells and macrophages in the human pineal gland. The prevalence of microglial cells over macrophages has been established. The morphological features and localization of the identified types of microglial cells indicate their participation primarily in immune defense, and also, probably, in the regulation of pinealocyte functions. In addition, data have been obtained indicating the participation of microglial cells in increasing inflammation in the human pineal gland during aging.

Association of gene polymorphisms with biological features of gastric cancer

Aim of the investigation. To evaluate associations of polymorphic variants of TNF (G308A), XPC (Lys939Gln), MTHFR (Ala222Val) genes with some biological features of gastric cancer. Materials and Methods. We evaluated polymorphic gene variants in 74 patients with verified gastric cancer or gastriesophageal junction cancer (Siewert III). Genotyping was performed by DNA isolation from venous blood leukocytes of the subjects followed by PCR with electrophoretic detection of the result. The association of polymorphic variants of genes with such biological features of the tumor as localization of the process, morphological type, degree of differentiation, type of tumor growth, presence or absence of lymphovascular or perineural invasion was evaluated. Results. Lys/Gln genotype of XPC gene (Lys939Gln) are 3.3 times more likely to develop gastric body cancer (p=0.04). Genotype GG of TNF gene (G308A) 5.3 times increases the development of gastric adenocarcinoma in comparison with other histological types (p=0.018), genotype GA of the same gene 5.2 times more often develop tumor with high-grade differentiation degree (p=0.032). Val/Val genotype of the MTHFR gene (Ala222Val) are significantly less likely to develop lymphatic/vascular invasion compared to carriers of the other genotype (p=0,029). Conclusion. The obtained data suggest that the genetic status of the patient itself may affect the biological characteristics of gastric cancer, which in turn may lead to a change in the patient’s treatment tactics.

Maintenance of inflorescence size variability within common buckwheat (Fagopyrum esculentum Moench) cultivars of various origin: the phenomenon and its possible causes

Background. Intrapopulation polymorphism usually can be interpreted as a result of balancing selection, but the basic mechanisms of such selection are not always clear. Earlier we documented a wide variation in the inflorescence size within one of the most genetically uniform common buckwheat (Fagopyrum esculentum Moench) cultivar ‘Skorospelaya 86’, with larger sizes controlled by recessive alleles of multiple genes. The objective of the present work was to analyze the variation within a set of buckwheat cultivars representing different morphological types of the crop, and try to make out possible mechanisms that underlie it. Material and methods. A set of buckwheat cultivars of various origin and belonging to different morphological types were analyzed. The size of inflorescences was assessed as a number of their iterative subunits, i.e., partial floret clusters (PFCs). The number of mature seeds in the entire inflorescence and various PFCs was also counted. Results and conclusions. All the cultivars were variable, with the range at the species level from 6 to 24 PFCs. Accumulation of the genes determining a larger inflorescence seems to be simply explained: larger inflorescences tended to produce more seeds than smaller ones. However, it is not so easy to explain the maintenance of the inflorescence size variability, i.e., why the alleles determining small inflorescences were not lost during the artificial selection for higher seed productivity. Probably, such polymorphism may be useful for maintaining heterosis at the population level.

Dynamic Coastal Mapping Using Sentinel-1 and Sentinel-2 Data Through Digital Earth Africa

Abstract. Coastal erosion poses a continuous threat to ecosystems, infrastructure, and property. To address these challenges and mitigate the effects of coastal changes, effective and current monitoring is essential. It is particularly important to monitor coastlines and coastal changes in Africa, where a significant portion of the population resides in coastal regions. While optical satellite imagery has been used for large-scale annual coastlines and change monitoring for Africa, its availability and quality are largely limited by the presence of cloud and cloud shadow. In comparison, using radar satellite observations such as Sentinel-1 data can provide consistent coastal mapping and change detection regardless of cloud presence. This paper outlines a fully automated supervised machine learning workflow using Sentinel-1 data and training samples extracted from Sentinel-2 data. It also explores the performance of the workflow for different coastal morphology types across the African coast. The workflow has proved to perform better and produced results that were visually more consistent with Sentinel-2 data compared to thresholding methods. While challenges exist to distinguish between land and water over smooth sandy beaches and rough near-shore water surfaces, our workflow provides an alternative method for coastal change mapping where optical satellites provide insufficient observations free from clouds. Python code of the proposed methodology has been made publicly available.

Leg length discrepancy risk differs between fit-and-fill and taper wedge stems across Dorr types.

The comparison between the cementless taper wedge stem and fit-and-fill stem in total hip arthroplasty (THA) for various proximal femoral morphological types has not been thoroughly assessed. This study aimed to compare the risk of leg length discrepancy (LLD) ≥ 10mm between these two stem types in Dorr type A, B, and C femurs. From April 2015 through April 2021, we analyzed 1178 unilateral primary cementless THA procedures. We categorized all procedures into three groups: Dorr type A (N = 220, 18.7%), B (N = 875, 74.3%), and C (N = 83, 7.0%). Within each Dorr type, we compared the incidence and risk of postoperative LLD ≥ 10mm between the two stem types. The factors considered in the multivariate regression analyses included stem type, age, sex, body mass index, diagnosis, canal flare index, femoral cortical index and stem alignment. The taper wedge stem group had a higher overall incidence of LLD ≥ 10mm (12.8% vs. 7.4%, P = 0.012) and in Dorr type A femurs (22.2% vs. 7.6%, P = 0.014), compared with the fit-and-fill stem group. In multivariate analysis, the taper wedge stem exhibited an increased risk of LLD ≥ 10mm only in Dorr type A femurs (aOR: 3.449, 95% CI: 1.325-8.794). The incidence and risk of LLD ≥ 10mm were not different between the two stems in Dorr type B and C femurs. The taper wedge stem demonstrated an elevated risk of LLD ≥ 10mm in Dorr type A femurs compared with the fit-and-fill stem, necessitating meticulous preoperative templating and intraoperative femoral canal preparation.

Constitutive modeling of the slip-twinning transition in martensitic transformations

Martensite is the result of a diffusionless displacive phase transition. In Fe-based alloys it transforms the FCC to the BCC, BCT, or HCP structures and occurs at high strain rates. It has two typical morphologies, known as lath and plate. A quantitative constitutive description of the slip-twinning transition in the martensitic transformation is presented. It is based on the temperature and strain-rate sensitivities of slip, which are much higher than those for twinning. Thus, twinning becomes a favored deformation mechanism at low temperatures and high strain rates. The Hall-Petch coefficient, for the inclusion of grain size effects, is two times larger for twinning than slip. Constitutive relationships for slip and twinning are presented and applied to the martensitic transformation in steels; the lath-to-plate morphology change observed with increasing carbon content is successfully predicted as a function of grain size by calculations incorporating the two modes of deformation. A simple calculation of the strain rates during martensitic transformation is also provided. This methodology is applied to the Fe–C system and can be extended to the Fe–Ni–C system and to thermoelastic martensites, where twinning is favored over slip to enhance reversibility.