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Hard ticks (Acari: Ixodidae) have been historically identified by morphological methods which require highly specialized expertise and more recently by DNA-based molecular assays that involve high costs. Although both approaches provide complementary data for tick identification, each method has limitations which restrict their use on large-scale settings such as regional or national tick surveillance programs. To overcome those obstacles, the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been introduced as a cost-efficient method for the identification of various organisms, as it balances performance, speed, and high data output. Here we describe the use of this technology to validate the distinction of two closely related Dermacentor tick species based on the development of the first nationwide MALDI-TOF MS reference database described to date. The dataset obtained from this protein-based approach confirms that tick specimens collected from United States regions west of the Rocky Mountains and identified previously as Dermacentor variabilis are the recently described species, Dermacentor similis. Therefore, we propose that this integrative taxonomic tool can facilitate vector and vector-borne pathogen surveillance programs in the United States and elsewhere.

A variety of scattering-based, microscopy-based, and mobility-based methods are frequently used to probe the size distributions of colloidal nanoparticles with transmission electron microscopy (TEM) often considered to be the "gold standard". Charge detection mass spectrometry (CDMS) is an alternative method for nanoparticle characterization that can rapidly measure the mass and charge of individual nanoparticle ions with high accuracy. Two low polydispersity, ∼100 nm diameter nanoparticle size standards with different compositions (polymethyl methacrylate/polystyrene copolymer and 100% polystyrene) were characterized using both TEM and CDMS to explore the merits and complementary aspects of both methods. Mass and diameter distributions are rapidly obtained from CDMS measurements of thousands of individual ions of known spherical shape, requiring less time than TEM sample preparation and image analysis. TEM image-to-image variations resulted in a ∼1-2 nm range in the determined mean diameters whereas the CDMS mass precision of ∼1% in these experiments leads to a diameter uncertainty of just 0.3 nm. For the 100% polystyrene nanoparticles with known density, the CDMS and TEM particle diameter distributions were in excellent agreement. For the copolymer nanoparticles with unknown density, the diameter from TEM measurements combined with the mass from CDMS measurements enabled an accurate measurement of nanoparticle density. Differing extents of charging for the two nanoparticle standards measured by CDMS show that charging is sensitive to nanoparticle surface properties. A mixture of the two samples was separated based on their different extents of charging despite having overlapping mass distributions centered at 341.5 and 331.0 MDa.

Microbial biofilms represent an important lifestyle for bacteria and are dynamic three-dimensional structures. Cyclic dimeric guanosine monophosphate (c-di-GMP) is a ubiquitous signaling molecule that is known to be tightly regulated with biofilm processes. While measurements of global levels of c-di-GMP have proven valuable toward understanding the genetic control of c-di-GMP production, there is a need for tools to observe the local changes of c-di-GMP production in biofilm processes. We have developed a label-free method for the direct detection of c-di-GMP in microbial colony biofilms using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). We applied this method to the enteric pathogen Vibrio cholerae, the marine symbiont V. fischeri, and the opportunistic pathogen Pseudomonas aeruginosa PA14 and detected spatial and temporal changes in c-di-GMP signal that accompanied genetic alterations in factors that synthesize and degrade the compound. We further demonstrated how this method can be simultaneously applied to detect additional metabolites of interest from a single sample.

UNLABELLED: Piscine lactococcosis is a significant threat to cultured and wild fish populations worldwide. The disease typically presents as a per-acute to acute hemorrhagic septicemia causing high morbidity and mortality, recalcitrant to antimicrobial treatment or management interventions. Historically, the disease was attributed to the gram-positive pathogen Lactococcus garvieae. However, recent work has revealed three distinct lactococcosis-causing bacteria (LCB)-L. garvieae, L. petauri, and L. formosensis-which are phenotypically and genetically similar, leading to widespread misidentification. An update on our understanding of lactococcosis and improved methods for identification are urgently needed. To this end, we used representative isolates from each of the three LCB species to compare currently available and recently developed molecular and phenotypic typing assays, including whole-genome sequencing (WGS), end-point and quantitative PCR (qPCR) assays, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), API 20 Strep and Biolog systems, fatty acid methyl ester analysis (FAME), and Sensititre antimicrobial profiling. Apart from WGS, sequencing of the gyrB gene was the only method capable of consistent and accurate identification to the species and strain level. A qPCR assay based on a putative glycosyltransferase gene was also able to distinguish L. petauri from L. garvieae/formosensis. Biochemical tests and MALDI-TOF MS showed some species-specific patterns in sugar and fatty acid metabolism or protein profiles but should be complemented by additional analyses. The LCB demonstrated overlap in host and geographic range, but there were relevant differences in host specificity, regional prevalence, and antimicrobial susceptibility impacting disease treatment and prevention. IMPORTANCE: Lactococcosis affects a broad range of host species, including fish from cold, temperate, and warm freshwater or marine environments, as well as several terrestrial animals, including humans. As such, lactococcosis is a disease of concern for animal and ecosystem health. The disease is endemic in European and Asian aquaculture but is rapidly encroaching on ecologically and economically important fish populations across the Americas. Piscine lactococcosis is difficult to manage, with issues of vaccine escape, ineffective antimicrobial treatment, and the development of carrier fish or biofilms leading to recurrent outbreaks. Our understanding of the disease is also widely outdated. The accepted etiologic agent of lactococcosis is Lactococcus garvieae. However, historical misidentification has masked contributions from two additional species, L. petauri and L. formosensis, which are indistinguishable from L. garvieae by common diagnostic methods. This work is the first comprehensive characterization of all three agents and provides direct recommendations for species-specific diagnosis and management.

Diet is inextricably linked to human health and biological functionality. Reduced cognitive function among other health issues has been correlated with a western diet (WD) in mouse models, indicating that increases in neurodegeneration could be fueled in part by a poor diet. In this study, we use matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) to spatially map the lipidomic profiles of male and female mice that were fed a high-fat, high-sucrose WD for a period of 7 weeks. Our findings concluded that the cortex and corpus callosum showed significant lipid variation by WD in female mice, while there was little to no variation in the hippocampus, regardless of sex. On the other hand, lipid profiles were significantly affected by sex in all regions. Overall, 83 lipids were putatively identified in the mouse brain; among them, HexCer(40:1;O3) and PE(34:0) were found to have the largest statistical difference based on diet for female mice in the cortex and corpus callosum, respectively. Additional lipid changes are noted and can serve as a metric for understanding the brain's metabolomic response to changes in diet, particularly as it relates to disease.

Intussusception is a familiar diagnosis among the pediatric population; however, it is rarely consideredamong the adult population due to a myriad of life-threatening pathologies within the abdomen. We presentan adult female who presented to the emergency department (ED) with abdominal pain and constipation.Laboratory testing and a computed tomography (CT) scan of the abdomen were ordered. Laboratory testresults were notable for an elevated lymphocyte count as well as leukocyte esterase, white blood cells (WBC),and bacteria seen on urinalysis. The computed tomography scan detected a colo-colic intussusceptionsecondary to a benign mass within the bowel lumen. The mass was surgically resected and the patient hadan uneventful postoperative course. This unique case represents the occurrence of a pathology to which theadult population is not immune, and therefore should not be overlooked when evaluating a non-specific caseof abdominal pain.

ABSTRACT: Aims: This study aims to review our experience of treating ovarian masses in children with an emphasis on clinical presentation, diagnosis, treatment, and outcome. Methods: We retrospectively reviewed the electronic medical records of all patients below 18 years of age who underwent surgical treatment for ovarian masses at our institute between 2009 and 2023. Study variables included demography, clinical presentation, physical findings, tumor markers, radiologic features, operative details, histopathology, follow-up status, and overall survival. Results: During the study period, 30 patients with a mean age of 10.07 years (range: 15 days–18 years) underwent surgical treatment for ovarian masses. Nonneoplastic ovarian masses were seen in 5 (16.7%) patients, whereas 25 (83.3%) patients had benign (10 [33.3%], borderline 3 [10%], or malignant 12 [40%]) ovarian neoplasms. The most common clinical presentation in the benign group was abdominal pain (n = 6), whereas painless abdominal mass (n = 6) was the predominant complaint in children with malignant tumors. A functional ovarian mass presenting with precocious puberty or virilization was seen in 5 (16.7%) patients. On imaging, nonneoplastic and benign lesions had a mean size of 4.33 (range: 3.1–6) cm and 12.63 (range: 2.8–28) cm, respectively, whereas borderline and malignant masses had a mean tumor size of 22.5 (range: 6.5–32) cm and 12.55 (range: 3.5–18.7) cm, respectively (P < 0.05). The cystic component was identified in all nonneoplastic and benign tumors, whereas the solid component was present in all borderline and malignant lesions (P < 0.05). Tumor markers such as serum alpha-fetoprotein and beta-human chorionic gonadotropin were raised in 8 (66.67%) of malignant tumors, whereas markers were normal in all benign lesions and borderline malignant lesions and 4 (33.33%) of malignant tumors. Lactate dehydrogenase (LDH) was also raised in all malignant masses (n = 12), whereas it was normal in all benign and borderline malignant masses (n = 18). In 6 (20%) patients with nonneoplastic and benign masses with maximum tumor size <6 cm, the laparoscopic approach was adopted, whereas open surgery was preferred in the rest of the patients. At a mean follow-up of 53.5 (range: 4–117) months, all patients are alive and disease free. Conclusions: Preoperative imaging characteristics (tumor size and solid component) and raised tumor markers may help us to differentiate between benign and malignant ovarian pathologies. The overall prognosis of pediatric ovarian tumors seems to be favorable. [ABSTRACT FROM AUTHOR]

In this article, we aim to examine and emphasize the need for management solutions to transform the standard tourism product of destination Bulgaria into a health-oriented one. The result of the set goal is the survey conducted among thirty Bulgarian tour operators or agencies of international ones operating on the Bulgarian Southern Black Sea coast, selected at random, with the potential to diversify their product. The presented analysis makes it possible to formulate recommendations and strategic guidelines for the reorientation of mass tourism towards health. [ABSTRACT FROM AUTHOR]

Caterpillars are important as food for many insectivorous birds. Their availability is highly seasonal in temperate regions. Global warming is known to advance this seasonality and can change the selection pressure on the seasonal timing of avian reproduction. Time series on caterpillar abundance and timing are often based on quantifying caterpillar faeces (called frass). Accurate estimates of caterpillar abundance and timing within and between years require temperature correction, the topic of this study. To estimate caterpillar abundance, we measured the rate of caterpillar frass production under tree crowns. To calculate the frass to caterpillar biomass conversion factor we kept wild caught caterpillars of a number of abundant species in cages outside and fed them daily with fresh leaves (Quercus robur or Betula sp.) in two studies, Dwingelderveld (Dv) and Hoge Veluwe (HV), in different time periods. We monitored caterpillar body mass and frass production on a 24-h time base to calculate the conversion factor as a function of temperature, study site, tree species and caterpillar species. One study (HV) concerned a reanalysis of earlier published data. The conversion factor strongly depended on ambient temperature, almost doubling from around 8 to 15 when daily temperatures reduced from 15 to 10°C, and differed somewhat between study areas and caterpillar species. Yet in 20 of 34 published studies that estimated seasonality in caterpillar abundance on the basis of frass fall, temperature was not corrected for. We illustrate the importance of the temperature correction of frass to mass conversion factors by comparing variation in raw frass data and temperature corrected caterpillar biomass estimates during the spring for 12 nest boxes in 16 years in the Dwingelderveld. We advise temperature correction of frass fall based estimates of caterpillar abundance in woodland, preferably based on local measurements in the study area and period. [ABSTRACT FROM AUTHOR]

PURPOSE To compare computed tomography (CT)-guided transthoracic lung biopsies (CTLB) with and without pre-procedure 18F-fludeoxyglucose positron emission tomography (18F-FDG PET)/CT images in the diagnosis of pulmonary nodules/masses. METHODS This is a case-control study in a single center. The data of patients with a transthoracic lung biopsy guided by CT and pre-procedure 18F-FDG PET/CT (group 2, here called the "PETCTLB" group), including demographics, clinical characteristics, and biopsy-related parameters, were collected. The PET/CT scan was performed within 15 days before the biopsy. The data from patients with CTLB were used as controls (group 1). Biopsies for all patients were performed by the same physician between January 2019 and December 2021. The final diagnosis was based on surgical outcomes, or imaging findings, and the results of at least one 6-month follow-up. The demographics and clinical characteristics of patients, lesions and biopsy-related variables, diagnostic yields, and incidence of complications were compared between the two groups. Two-tailed t-tests were used to compare the mean values in the two independent groups, while categorical variables were compared using the Pearson chi-squared test, and P values < 0.05 were considered to be significant. RESULTS A total of 84 patients were included, and 84 biopsies of 84 lung nodules/masses were analyzed. The demographics and clinical characteristics of group 2 (n = 39; 21 men; mean age, 63.2 ± 9.29 years) and group 1 (n = 45; 30 men; mean age, 61.2 ± 12.3 years) had no significant difference (P = 0.230 and 0.397, respectively). The procedure duration (11.1 ± 3.0 vs. 12.9 ± 3.3 minutes, P = 0.008), the number of samples (2.6 ± 0.5 vs. 3.1 ± 0.4, P < 0.001), diagnostic accuracy (97.4% vs. 82.2%, P = 0.033), and bleeding complication (25.6% vs. 42.2%, P = 0.034) of group 2 and group 1 were statistically different. CONCLUSION A biopsy guided by CT plus pre-procedure 18F-FDG PET/CT (PETCTLB) is a safe procedure that can provide a precise diagnosis in the majority of lung nodules/masses. It has better diagnostic performance than CTLB. [ABSTRACT FROM AUTHOR]

A vibration test to measure the mass of a specimen without weighing it using the difference between the resonance frequency with an additional mass and that without it (vibration method with additional mass, VAM) was applied to Japanese cedar flat square lumber with dimensions of 210 mm × 135 mm × 3000 mm both with and without a pith in the process of air-drying. The longitudinal and bending vibration tests were performed on the specimens with and without an additional mass. The accuracy of VAM that was expressed by the estimated mass by VAM to the measured mass (MVAM/M0) was sufficiently high throughout the air-drying process. The accuracy of VAM for the longitudinal vibration was higher than that for the bending vibration. The moisture content based on the estimated mass by VAM was in the expected range. [ABSTRACT FROM AUTHOR]

Myofibromatosis is a proliferative disorder characterized by the development of soft tissue neoplasms referred to as myofibromas that predominantly occur in infants and young children. These lesions have been described using varied terminologies since they were first reported in 1951. However, these neoplasms are histopathologically characterized by benign fibroblast and myofibroblast proliferation containing a biphasic presentation of spindle-shaped cells surrounding a central zone of less differentiated cells arranged in a hemangiopericytoma-like pattern in all cases. Usually, myofibromatosis occurs in children aged <2 years and is observed at birth in nearly 60% of cases. We report a rare case of myofibroma in an 8-year-old boy who presented with an approximately 6-month history of a left postauricular mass. Histopathological evaluation of the resected mass confirmed the diagnosis. [ABSTRACT FROM AUTHOR]

Discussions surrounding Maritime Autonomous Surface Ships (MASS) are occurring in academia, industry, and the International Maritime Organization (IMO). Automatic collision avoidance, as one of the key technologies of MASS, is the core of the autonomous navigation function of MASS, and its role is to solve the autonomous collision avoidance problem during MASS navigation. Convention on the International Regulations for Preventing Collisions at Sea (COLREGS) is a fundamental basis for automatic collision avoidance, and the navigation of MASS should adhere to it. However, the applicability of MASS to COLREGS has not yet been resolved. Responding to these issues, the paper proceeds to analyze the principal challenges of MASS to COLREGS in terms of the application of MASS to good seamanship, the neglect provision, the lookout provision, the insight of one another provision, and the problems of the deviation provision. Furthermore, suggestions are put forth for the revision of COLREGS, including the mode of revision, the reconstruction of MASS collision liability, the long-term coexistence of MASS and traditional ships, and the risk control of COLREGS revision in the context of artificial intelligence. These suggestions aim to establish a foundation for a more effective adaptation to the advent of the MASS era. [ABSTRACT FROM AUTHOR]

Highlights The engineering structures with cutouts should consider both buckling and stiffness. Inspired by the multi‐level leaf veins, in this paper, the skeleton of the grid‐honeycomb sandwich structure was designed in the hierarchical form, and combined with the cutout characteristics of the side walls of the railway vehicle body, the multi‐objective stiffness and mass optimization of the skeleton layout under buckling constraints was achieved. The cutout honeycomb sandwich structure was designed with orthogonal grids in the stiffness design area and curved grids based on the quadratic polynomial in the buckling design area. The optimization model also included the linear angle hierarchical grid, the constant angle hierarchical grid, and the single‐level orthogonal grid. The multi‐objective optimization framework based on the Radial Basis Function (RBF) surrogate model and the Non‐dominated Sorting Genetic Algorithm (NSGA‐II) was developed. The optimization results indicated that the hierarchical grid provided the more extensive design space. The optimal solution of the quadratic polynomial hierarchical grid had the highest stiffness and stiffness per unit mass compared to the rest of the grid layouts, which were 23.28% and 30.47% higher than the single‐level orthogonal grid, respectively. Finally, the multi‐order eigenvalue buckling was analyzed based on the optimal structure. Layout of hierarchical grids proposed inspired by multi‐level leaf veins. Orthogonal grids ensure stiffness and curved grids inhibit buckling at cutouts. Apply the hierarchical grids as skeletons to honeycomb sandwich structures. Stiffness and mass optimization subject to buckling constraints is performed. [ABSTRACT FROM AUTHOR]

Ice hockey is a fast-paced sport with a high incidence of collisions between players. Shoulder checks are especially common, accounting for a large portion of injuries including concussions. The forces generated during these collisions depend on the inertial and viscoelastic characteristics of the impacting bodies. Furthermore, the effect of shoulder pads in reducing peak force depends on the baseline (unpadded) properties of the shoulder. We conducted experiments with nine men's ice hockey players (aged 19–26) to measure their effective shoulder stiffness, damping and mass during the impact stage of a shoulder check. Participants delivered a style of check commonly observed in men's university ice hockey, involving lateral impact to the deltoid region, with the shoulder brought stationary by the collision. The effective stiffness and damping coefficient of the shoulder averaged 12.8 kN/m and 377 N-s/m at 550 N, and the effective mass averaged 47% of total body mass. The damping coefficient and stiffness increased with increasing force, but there was no significant difference in the damping coefficient above 350 N. Our results provide new evidence on the dynamics of shoulder checks in ice hockey, as a starting point for designing test systems for evaluating and improving the protective value of shoulder pads. [ABSTRACT FROM AUTHOR]

Purpose: To describe features of a syphilitic vascularized iris mass on multimodal imaging and its resolution after penicillin treatment. Methods: Observational case report and literature review of syphilitic iris masses. Results: A 43-year-old woman presented with a unilateral vascularized tan iris mass in the setting of bilateral panuveitis that occurred along with bilateral papillitis, cystoid macular edema and retinal vasculitis. Laboratory work-up confirmed a diagnosis of syphilis. Ultrasound biomicroscopy (UBM) of the iris mass showed parapupillary hyperechoic full-thickness iris stromal thickening with small intrinsic circular lumens without cyst or ciliary body extension, while the anterior segment optical coherence tomography (AS-OCT) demonstrated a hyperreflective mass with deep iris extension and partial hyporeflective rim. Following treatment, the mass fully resolved without residual sequela. A review of literature identified 11 additional cases of syphilitic iris masses in the English literature from 1915 to present. Their presentations and clinical courses were reviewed herein. Conclusions: This report characterizes a syphilitic iris mass on slit-lamp photography, iris fluorescein angiography, UBM and AS-OCT; depicts key characteristics of syphilitic iris masses; and highlights the need for close inspection of the iris mass as an uncommon sign of ocular syphilis. [ABSTRACT FROM AUTHOR]

Breast cancer persists as a critical global health concern, emphasizing the advancement of reliable diagnostic strategies to improve patient survival rates. To address this challenge, a computer-aided diagnostic methodology for breast cancer classification is proposed. An architecture that incorporates a pre-trained EfficientNet-B0 model along with channel and spatial attention mechanisms is employed. The efficiency of leveraging attention mechanisms for breast cancer classification is investigated here. The proposed model demonstrates commendable performance in classification tasks, particularly showing significant improvements upon integrating attention mechanisms. Furthermore, this model demonstrates versatility across various imaging modalities, as demonstrated by its robust performance in classifying breast lesions, not only in mammograms but also in ultrasound images during cross-modality evaluation. It has achieved accuracy of 99.9% for binary classification using the mammogram dataset and 92.3% accuracy on the cross-modality multi-class dataset. The experimental results emphasize the superiority of our proposed method over the current state-of-the-art approaches for breast cancer classification. [ABSTRACT FROM AUTHOR]

Sarcoid myositis is a rare and often debilitating extrapulmonary manifestation of sarcoidosis that can be difficult to recognize without a prior sarcoidosis diagnosis. Sarcoidosis with muscle nodules or masses as the first symptom is the least common form, occurring in approximately 0.5%–2.3% of cases. This article presents four middle‐aged female patients who initially sought medical attention for a lower limb mass. Ultrasound examinations revealed consistent characteristic changes indicative of myositis. All patients underwent ultrasound‐guided muscle biopsy and were diagnosed with sarcoidosis. Therefore, ultrasonography plays a pivotal role as the primary diagnostic tool for the early detection of sarcoid myositis. [ABSTRACT FROM AUTHOR]

The maritime sector is increasingly integrating Information and Communication Technology (ICT) and Artificial Intelligence (AI) technologies to enhance safety, environmental protection, and operational efficiency. With the introduction of the MASS Code by the International Maritime Organization (IMO), which regulates Maritime Autonomous Surface Ships (MASS), ensuring the safety of AI-integrated systems on these vessels has become critical. To achieve safe navigation, it is essential to identify potential risks during the system planning stage and design systems that can effectively address these risks. This paper proposes RA4MAIS (Risk Assessment for Maritime Artificial Intelligence Safety), a risk identification method specifically useful for developing AI-integrated maritime systems. RA4MAIS employs a systematic approach to uncover potential risks by considering internal system failures, human interactions, environmental conditions, AI-specific characteristics, and data quality issues. The method provides structured guidance to identify unknown risk situations and supports the development of safety requirements that guide system design and implementation. A case study on an Electronic Chart Display and Information System (ECDIS) with an AI-integrated collision avoidance function demonstrates the applicability of RA4MAIS, highlighting its effectiveness in identifying specific risks related to AI performance and reliability. The proposed method offers a foundational step towards enhancing the safety of software systems, contributing to the safe operation of autonomous ships. [ABSTRACT FROM AUTHOR]

This work examines the utilization of negative mass and negative stiffness principles to enhance the effectiveness of Dynamic Vibration Absorbers (DVAs) for vibration attenuation developed in structures. The proposed idealized model aims to reduce the amplitude of resonance and expand the frequency stopband range to achieve vibration reduction by attaching two parallel dynamic vibration absorbers to the primary system. By incorporating stiffness, mass, and damping ratio for each one of the absorbers and in the presence of harmonic excitation, it is possible to expand the frequency range in which vibration may be suppressed, leading to a substantial decrease in the maximum vibration amplitude of the primary system and the stroke length of the absorbers. The Nelder-Mead method is successfully used as an optimization tool to obtain the best selection of the absorbers' design parameters that assure the best vibration attenuation and frequency stopband. The results indicate a strong association between the change in frequency and the decrease in vibration. In the instance of frequency response, the vibration amplitude decreased by an average of 91.46% across all three modes of the whole system. Another optimal selection exhibited the most significant enhancement, achieving an average reduction in vibration amplitude of 97.06% across all three modes. Finally, the results indicate that the suggested lumped parallel architecture of the absorbers with precisely adjusted negative mass and negative stiffness characteristics along with the presented optimization method, can greatly improve the effectiveness of reducing vibrations in various applications. The results illustrate a direct relationship between shifts in frequency and vibration. If the value of the shift is greater than 1 the vibration is decreased, while less than 1 means the worst form of reducing such magnitude. The most notable drop off in amplitude occurred when averaging a simple drop off of up to 91.46% for all three patterns where frequency shifts by Y=2.008. [ABSTRACT FROM AUTHOR]

Background Development of rapid bacterial identification from blood cultures has been an area of intense study in diagnostic microbiology. Shortened turnaround time coupled with antimicrobial stewardship interventions have been shown to improve patient outcomes and decrease healthcare-associated costs. Objectives We report the validation of a short incubation method for Gram-positive and Gram-negative bacterial identification utilizing MALDI-TOF MS without additional instrumentation, processing or cost compared with current practice. Methods Prospective, observational, single-centre study in a quaternary care academic hospital encompassing 376 blood cultures subjected to bacterial identification after short incubation periods of 3–4 and 6–8 h. Results There was 97.5% species-level identification agreement with tests undertaken after 3–4 h incubation with 83.6% isolates identified, and 99.7% species-level identification agreement after 6–8 h incubation with 96.7% isolates identified. Conclusions The short incubation method provides a rapid MALDI-TOF MS bacterial identification method, reducing turnaround time by 10–18 h compared with standard practice without additional cost, processing or instrumentation. [ABSTRACT FROM AUTHOR]

Detection and identification of microorganisms are the first steps to guide susceptibility testing and enable clinicians to confirm diseases and guide therapy. The faster the pathogen identification is determined, the quicker the appropriate treatment can be started. In the clinical microbiology laboratory, multiple methodologies can be used to identify organisms, such as traditional biochemical testing or more recent methods like MALDI TOF MS and nucleic acid detection/identification assays. Each of these techniques has advantages and limitations, and clinical laboratories need to determine which methodology is best suited to their particular setting in terms of clinical needs, availability of technical expertise and cost. This article presents a concise review of the history, utilization, advantages and limitations of the main methods used for identifying microorganisms in microbiology laboratories. [ABSTRACT FROM AUTHOR]

Background: muscle mass (MM) plays an important role in the physical function of hemodialysis patients; however, muscle mass measurement can be unreliable and expensive. In contrast, the measurement of physical function (PF) is simple and inexpensive and may serve as an alternative. The aim of this study was to correlate the measurement of MM by computed tomography (CT) with physical function measurements and physical activity (PA) levels in HD patients. Methods: this was a cross-sectional study that included 38 HD patients from a single HD clinic. Each participant had a CT scan to measure mid-thigh muscle mass. Physical function tests were assessed using the six-minute walk test (SMWT), handgrip strength (HGS) test, 5 x sit-tostand test (STS5), timed up and go test (TUGT) and Short Physical Performance Battery (SPPB), while physical activity levels were measured using the Godin-Shephard leisure-time physical activity questionnaire. Correlation analysis was used to examine the relationship between variables. Results: handgrip strength was strongly positively correlated with thigh muscle area (r = 0.656, p ≤ 0.001) and weakly correlated with arm muscle area (r = 0.396, p = 0.002), SMWT (r = 0.373, p = 0.004), SPPB (r = 0.269, p = 0.041) and physical activity (r = 0.323, p = 0.013). There was also a trend for an inverse correlation between handgrip strenght and TUGT (r = -0.235, p = 0.076). Positive correlations were found between the thigh muscle area and the SPPB (r = 0.339, p = 0.009) and PA (r = 0.293, p = 0.025), while there was a trend for an inverse correlation between thigh muscle area and STS5 (r = -0.256, p = 0.052). Conclusion: several measures of PF and strenght were correlated with objectives measurements of MM, thus provide options for low-cost measurements related to muscle mass. [ABSTRACT FROM AUTHOR]

This paper proposes a novel memory state-feedback control (MSFC) strategy for multiagent systems (MASs) operating on time scales. The communication topology is modeled by a collection of directed graphs with switching edges. We analyze the exponential stability of the error dynamics within a leader-follower synchronization framework, crucial for MAS control. Employing linear matrix inequalities (LMIs) and Lyapunov-Krasovskii functionals (LKFs), we establish sufficient conditions to guarantee global exponential stability for the considered systems. Notably, the synchronization conditions for MASs on different time scales differ from those on discrete or continuous time scales alone. This approach allows for a unified framework encompassing both discrete and continuous-time global synchronization problems, Finally, a simulation study utilizing a neural network (NN)-based circuit model demonstrates the effectiveness of the proposed control design. [ABSTRACT FROM AUTHOR]

Radiotherapy plays a key role in the treatment of the early and advanced stages of head and neck cancer. To date, there is still no consensus on the effects of radiotherapy on the mechanical properties of fluoride-releasing restorative materials which can be used in patients undergoing radiotherapy with increased incidence of caries. The fluoride-releasing materials Equia Forte HT and Cention N were compared to the resin-based materials Tetric EvoCeram and Tetric Power Fill. Standard irradiation was performed with a linear accelerator. Vickers microhardness, mass, surface roughness and color were measured before and after irradiation. Cention N and Tetric PowerFill showed stability in the mass, while the surface roughness did not change in any of the examined groups. Resistance to microhardness change was shown by Cention N, Tetric PowerFill and Tetric EvoCeram, and the color change was significant in all groups (p < 0.05). It should be remembered that patients receiving head and neck radiation therapy may experience adverse effects from the treatment, including changes in the mechanical properties of the restorative materials. The obtained results suggest that Cention N can be used as a material in patients undergoing head and neck radiotherapy due to the mechanical stability and depo effect of fluoride release. [ABSTRACT FROM AUTHOR]

Herbaspirillum huttiense is an opportunistic pathogen associated with rare cases of bacteremia. In this case report, H huttiense was isolated from blood samples collected from an intravenous catheter (incubated for 20.8 hours) and a peripheral vein (incubated for 14.16 hours) of a lung adenocarcinoma patient. Positive blood culture bottles were subjected to smear preparation, and Gram staining and microscopic examination revealed the presence of gram-negative rods in both aerobic bottles. We used the VITEK MS automatic microbial mass spectrometry system, VITEK 2 Compact automatic microbial analysis system, and high-throughput nucleic acid sequencing for accurate identification of the isolate. It is noteworthy that although the VITEK 2 Compact identified the isolate as Burkholderia cepacia , confirmation through VITEK MS mass spectrometry and 16S ribosomal DNA (rDNA) sequencing identified it as H huttiense. Subsequently, antimicrobial susceptibility testing was performed using the broth microdilution method, following the guidelines for nonfermenting gram-negative bacilli provided by the Clinical and Laboratory Standards Institute. This case highlights the possibility of misidentification of H huttiense as B cepacia by VITEK 2 Compact in certain situations, emphasizing the importance of considering uncommon pathogens, such as H huttiense , in the context of bacteremia in cancer patients. [ABSTRACT FROM AUTHOR]

Background The differential diagnosis of tricuspid masses remains challenging. Case summary This case involves the incidental detection of a lesion with a non-solid appearance, exhibiting the characteristic 'finger-in-glove' and 'garland-like' morphology, resembling a blind-ended protrusion of the tricuspid leaflet. This presentation is consistent with a tricuspid valve aneurysm, without significant associated stenosis or regurgitation. Discussion Given the lesion's morphological features, the patient's asymptomatic status, and the absence of a precipitating event suggestive of an alternative diagnosis, we concluded that the most likely diagnosis is aseptic tricuspid valve aneurysm. Following a multidisciplinary heart team discussion, surgical intervention was deemed unnecessary. [ABSTRACT FROM AUTHOR]

Background Intracardiac masses are historically treated with surgery. As percutaneous technologies continue to evolve, non-surgical techniques for mass removal may become options. We present a case of a woman with a large right atrial mass that was percutaneously removed en bloc without surgery. Case summary A 77-year-old woman presents with a 40 mm right atrial mass. The mass was increasing in size, and she preferred to avoid surgical removal. The tumour was removed percutaneously from the femoral vein using a large suction cannula in combination with transection of the stalk using an electrified snare. The case was complicated by a haemopericardium that was treated successfully by injecting a haemostatic matrix into the pericardial space. The pathology returned papillary fibroelastoma. Discussion The TEXAS technique used to remove the right atrial mass in this case is a modification of a previously described technique (SEATTLE procedure). Using this method, we were able to remove a 40 mm tumour from the right atrium without surgery. This is the largest reported intracardiac tumour that has been removed en bloc percutaneously. Percutaneous removal of right atrial tumours appears feasible, although this may be limited to smaller tumours based on the results of our case. [ABSTRACT FROM AUTHOR]

PURPOSE: To compare computed tomography (CT)-guided transthoracic lung biopsies (CTLB) with and without pre-procedure 18F-fludeoxyglucose positron emission tomography (18F-FDG PET)/CT images in the diagnosis of pulmonary nodules/masses. METHODS: This is a case-control study in a single center. The data of patients with a transthoracic lung biopsy guided by CT and pre-procedure 18F-FDG PET/CT (group 2, here called the “PETCTLB” group), including demographics, clinical characteristics, and biopsy-related parameters, were collected. The PET/CT scan was performed within 15 days before the biopsy. The data from patients with CTLB were used as controls (group 1). Biopsies for all patients were performed by the same physician between January 2019 and December 2021. The final diagnosis was based on surgical outcomes, or imaging findings, and the results of at least one 6-month follow-up. The demographics and clinical characteristics of patients, lesions and biopsy-related variables, diagnostic yields, and incidence of complications were compared between the two groups. Two-tailed t-tests were used to compare the mean values in the two independent groups, while categorical variables were compared using the Pearson chi-squared test, and P values < 0.05 were considered to be significant. RESULTS: A total of 84 patients were included, and 84 biopsies of 84 lung nodules/masses were analyzed. The demographics and clinical characteristics of group 2 (n = 39; 21 men; mean age, 63.2 ± 9.29 years) and group 1 (n = 45; 30 men; mean age, 61.2 ± 12.3 years) had no significant difference (P = 0.230 and 0.397, respectively). The procedure duration (11.1 ± 3.0 vs. 12.9 ± 3.3 minutes, P = 0.008), the number of samples (2.6 ± 0.5 vs. 3.1 ± 0.4, P < 0.001), diagnostic accuracy (97.4% vs. 82.2%, P = 0.033), and bleeding complication (25.6% vs. 42.2%, P = 0.034) of group 2 and group 1 were statistically different. CONCLUSION: A biopsy guided by CT plus pre-procedure 18F-FDG PET/CT (PETCTLB) is a safe procedure that can provide a precise diagnosis in the majority of lung nodules/masses. It has better diagnostic performance than CTLB.

Abstract A vibration test to measure the mass of a specimen without weighing it using the difference between the resonance frequency with an additional mass and that without it (vibration method with additional mass, VAM) was applied to Japanese cedar flat square lumber with dimensions of 210 mm × 135 mm × 3000 mm both with and without a pith in the process of air-drying. The longitudinal and bending vibration tests were performed on the specimens with and without an additional mass. The accuracy of VAM that was expressed by the estimated mass by VAM to the measured mass (M VAM/M 0) was sufficiently high throughout the air-drying process. The accuracy of VAM for the longitudinal vibration was higher than that for the bending vibration. The moisture content based on the estimated mass by VAM was in the expected range.

Technologies assessing the lipidomics, genomics, epigenomics, transcriptomics, and proteomics of tissue samples at single-cell resolution have deepened our understanding of physiology and pathophysiology at an unprecedented level of detail. However, the study of single-cell spatial metabolomics in undecalcified bones faces several significant challenges, such as the fragility of bone, which often requires decalcification or fixation leading to the degradation or removal of lipids and other molecules. As such, we describe a method for performing mass spectrometry imaging on undecalcified spine that is compatible with other spatial omics measurements. In brief, we use fresh-frozen rat spines and a system of carboxyl methylcellulose embedding, cryofilm, and polytetrafluoroethylene rollers to maintain tissue integrity while avoiding signal loss from variations in laser focus and artifacts from traditional tissue processing. This reveals various tissue types and lipidomic profiles of spinal regions at 10 μm spatial resolutions using matrix-assisted laser desorption/ionization mass spectrometry imaging. We expect this method to be adapted and applied to the analysis of the spinal cord, shedding light on the mechanistic aspects of cellular heterogeneity, development, and disease pathogenesis underlying different bone-related conditions and diseases. This study furthers the methodology for high spatial metabolomics of spines and adds to the collective efforts to achieve a holistic understanding of diseases via single-cell spatial multiomics.

Detection of small molecule metabolites (SMM), particularly those involved in energy metabolism using MALDI-mass spectrometry imaging (MSI), is challenging due to factors including ion suppression from other analytes present (e.g., proteins and lipids). One potential solution to enhance SMM detection is to remove analytes that cause ion suppression from tissue sections before matrix deposition through solvent washes. Here, we systematically investigated solvent treatment conditions to improve SMM signal and preserve metabolite localization. Washing with acidic methanol significantly enhances the detection of phosphate-containing metabolites involved in energy metabolism. The improved detection is due to removing lipids and highly polar metabolites that cause ion suppression and denaturing proteins that release bound phosphate-containing metabolites. Stable isotope infusions of [13C6]nicotinamide coupled to MALDI-MSI (Iso-imaging) in the kidney reveal patterns that indicate blood vessels, medulla, outer stripe, and cortex. We also observed different ATP:ADP raw signals across mouse kidney regions, consistent with regional differences in glucose metabolism favoring either gluconeogenesis or glycolysis. In mouse muscle, Iso-imaging using [13C6]glucose shows high glycolytic flux from infused circulating glucose in type 1 and 2a fibers (soleus) and relatively lower glycolytic flux in type 2b fiber type (gastrocnemius). Thus, improved detection of phosphate-containing metabolites due to acidic methanol treatment combined with isotope tracing provides an improved way to probe energy metabolism with spatial resolution in vivo.

Abstract Introduction and importance Fibroepithelial polyps are rare benign lesions with uncertain origins. They are commonly found in the skin and genitourinary system. Fibroepithelial polyps in the external auditory canal are infrequent. Case presentation We report a 60-year-old Persian woman with an incidentally discovered painless fibroepithelial polyp in the right external auditory canal. Microscopic transcanal surgery confirmed the diagnosis after temporal computed tomography imaging showed a soft tissue mass. Clinical discussion Fibroepithelial polyps have an uncertain etiology and are typically asymptomatic. Surgical resection is the preferred treatment, and the prognosis following resection is generally favorable, with low recurrence rates. Conclusion This case highlights the rarity of fibroepithelial polyps in the external auditory canal and underscores the importance of considering them in the differential diagnosis of external auditory canal lesions.

Common benign subcutaneous benign masses and pseudomasses represent a wide spectrum of masses among which lipomas and epidermal cysts account for a vast majority of the lesions encountered in routine practice. Other types of tumors originate from various components of the skin, such as the pilous tract, nerves, veins, arteries, or eccrine glands. In some instances, pseudomasses may be distinguished from tumoral masses using specific signs. When the diagnosis of a subcutaneous lesion lacks specificity for benignity with ultrasound, radiologists should ensure proper management of the patient to rule out the possibility of a rare but possible sarcoma of the subcutaneous layer. [ABSTRACT FROM AUTHOR]

Objective To compare the detective and diagnostic ability of full field digital mammography (FFDM) alone and digital breast tomosynthesis (DBT) combined with FFDM (FFDM+DBT) in different types of lesions. Method A total of 389 patients who underwent preoperative mammography in Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from November 2021 to June 2022 were prospectively included in this study. FFDM images and DBT images were obtained from each patient in the Combo mode. All images were interpreted by senior radiologists, who have been involved in breast imaging diagnosis for more than 10 years. Using the pathological results as the gold standard, the consistency between the imaging evaluation and the gold standard was analyzed to evaluate the differences in diagnostic efficacy between FFDM and DBT (FFDM+DBT), and the differences in diagnostic efficacy in different types of lesions. Indice of diagnostic efficacy includes sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), area under curve (AUC) receiver operating characteristic curve (ROC) for diagnosing breast cancer and overall diagnostic ability between FFDM and FFDM+DBT were compared. Results The overall diagnostic capability of FFDM+DBT was significantly improved compared with FFDM alone (P

Introduction. Forward plate compactors are surface soil compaction machines with a flat operating device, which are usually equipped with a single-shaft vibration exciter. Forward plate compactors may be driven by gasoline, diesel or electric engines. When designing and modernizing forward plate compactors, a problem of technical specifications justification may arise, including such parameters as exciting force, vibration exciter oscillation frequency, engine power, base plate width, etc. This statistical analysis of plate compactors with different types of engines was carried out to summarize manufacturers practices and reveal correlations between the technical specifications of forward plate compactors.Materials and methods. This research is based on the information presented on the official websites of forward plate compactors manufacturers and their dealers. 644 models of forward plate compactors were scrutinized. Regression equations and correlation coefficients were derived using Microsoft Excel software.Results. Parameters ranges for forward plate compactors with different types of engines were determined. Regression equations of correlations between oscillation frequency, exciting force, engine power, base plate width, relative exciting force and mass of forward plate compactors with different types of engines were derived, as well as the corresponding correlation coefficients. It was revealed, that most parameters have low or very low correlation coefficient, regardless of the engine type.Conclusion. The ranges of the technical specifications of diesel and gasoline forward plate compactors are quite close to each other. The parameters ranges of electric plate compactors, in most cases, are beyond the ranges of gasoline and diesel plate compactors. Low correlation coefficients and a large scatter of parameters indicate that manufacturers do not have a methodology for justification of the technical specifications of forward plate compactors. Results of the study may be used when clarify ranges of parameters and formulate requirements for a mathematical model of vibration plates behavior.

Rhabdomyosarcoma is a malignant tumor in children that might mimic a benign tumor, such as infantile hemangioma, particularly when detected early. Although rhabdomyosarcoma rarely occurs in the hand, its prognosis is generally poor, and successful treatment relies on a complete and radical surgical excision. We present a case of rhabdomyosarcoma located in the palm of an infant's hand, initially presenting clinical and radiological features suggestive of a vascular tumor. The resection of this mass was radical, and histological analysis and immunohistochemistry returned in favor of embryonic rhabdomyosarcoma. In similar cases recorded in the literature, the diagnosis may be first mistaken for that of a hemangioma, then confirmed by histology. This underlines the importance of a systematic anatomopathological examination of all tissues removed surgically.

Background: Sparse recent data are available regarding the aetiological causes of the right iliac fossa (RIF) mass from Andhra Pradesh. Methods: We prospectively studied the clinical presentation, diagnosis and management of consecutive cases (n = 100) presenting to our tertiary care teaching hospital with a RIF mass over 2 years. Results: Majority of RIF masses were seen in the third and fourth decades of life, and the male-to-female ratio was 2.8:1; 64% of the cases were due to appendicular pathology (appendicular mass [48%] and appendicular abscess [16%]), followed by ileocaecal tuberculosis (TB) (12%) and carcinoma caecum (10%) among others. Carcinoma caecum was more common in males (70%) as compared to females (30%). The majority (78%) were managed surgically; 4% died. Post-operative complications included wound infection and respiratory tract infection. Conclusions: Our observations suggest that appendicular pathology, ileocaecal TB and carcinoma caecum are common aetiological causes for RIF mass. Abdominal ultrasonography and computed tomography will facilitate early localisation.

Abstract Purpose To evaluate the intracavity left ventricular (LV) blood flow kinetic energy (KE) parameters using four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) in patients with acute myocardial infarction (AMI). Methods Thirty AMI patients and twenty controls were examined via CMR, which included cine imaging, late gadolinium enhancement (LGE) and global heart 4D flow imaging. The KE parameters were indexed to LV end-diastolic volume (EDV) to obtain average, systolic and diastolic KE as well as the proportion of LV in-plane KE (%). These parameters were compared between the AMI patients and controls and between the two subgroups. Results Analysis of the LV blood flow KE parameters at different levels of the LV cavity and in different segments of the same level showed that the basal level had the highest blood flow KE while the apical level had the lowest in the control group. There were no significant differences in diastolic KE, systolic in-plane KE and diastolic in-plane KE between the anterior wall and posterior wall (p > 0.05), only the systolic KE had a significant difference between them (p

A study was conducted on the changes in sea surface temperature (SST) on the southwestern shelf of the Crimea between 2000 and 2020. The equations of trends in the change of SST were found. It is shown that the following three periods can be distinguished according to the nature of changes in the average annual sea temperature: 2000 - 2007, 2008-2013 and 2014 - 2020. The influence of changes in the average annual SST on the development of pelagic fish of the cold-water complex was considered (using the example of the Black Sea sprat). Changes in the main parameters of the populations and their relationship with the change in the average annual SST were determined. It was found that the increase in sea temperature negatively affected the development of the sprat population, and the average age of the population decreased by 1.3 times. In general, the population was rejuvenated, and the average size and weight of individuals decreased.

The compressive strength of sandcrete block is a very important aspect of a block in a building. In many cases of building failures in Nigeria, the strength of the sandcrete block, has been figured as one of the causes of the failure. Hence the objective of this paper was to model and optimize the mass density for strength and durability of sandcrete block from okhuare in Edo State, Nigeria using standard methods. The mass of block was minimized, density was maximized, failure load was maximized, water absorption was minimized and compressive strength was maximized. Mass is 27.3287, density is 2149.19, failure load is 234.861, water absorption is 6.60831 and compressive strength is 4.08817. The optimum value of process parameters were determined. Water is 0.56, cement is 0.42, sand is 10.00. The experiment was performed and the results accurately measured and a mathematical model that can adequately explain the effects of the process parameters on the strength and durability of the sandcrete block was developed and the most significant factor influencing the strength of the block was identified. [ABSTRACT FROM AUTHOR]

Key summary points: Aim: In this study, the cross-sectional area of the geniohyoid muscle was investigated using ultrasonography to determine the normative and cut-off values. Findings: The cut-off values of the ultrasonographic cross-sectional area of the geniohyoid muscle were found as 172.5 mm2 for women and 194.7 mm2 for men. Message: This cut-off values could help detect loss of swallowing muscle mass and contribute to the diagnosis of sarcopenic dysphagia. Purpose: Determining the strength and area of the swallowing muscles is important in patients with sarcopenic dysphagia. Although the normative data on the strength of the swallowing muscles have been reported, those of the area of the geniohyoid muscle are poorly investigated. We investigated the cross-sectional area of the geniohyoid muscle in Japanese subjects without dysphagia using ultrasonography to determine the normative and cut-off values. Methods: 142 subjects without dysphagia were included. The older group (age ≥ 65 years) included 36 (women 27/men 9) subjects, and the younger group (age ≤ 39 years) included 106 (women 54/men 52) subjects. The cross-sectional area of the geniohyoid muscle was measured by ultrasound. The mean of the younger group-2 standard deviation (SD) was calculated and used as a cut-off value for low swallowing muscle mass. Results: The mean (SD) of the area of the geniohyoid muscle of each group was as follows: older women group 167.2 (32.6) mm2, older men group 193.2 (49.5) mm2, younger women group 247.3 (37.4) mm2, younger men group 313.1 (59.2) mm2. The mean 2SD of the geniohyoid muscle area in the younger women group was 172.5 mm2 and in the younger men group 194.7 mm2. Conclusion: We found that the cut-off value of the ultrasonographic cross-sectional area of the geniohyoid muscle was 172.5 mm2 for women and 194.7 mm2 for men. These values could be used as cut-off values for the mass of the geniohyoid muscle to identify patients with sarcopenic dysphagia. [ABSTRACT FROM AUTHOR]

The formation tracking of the leader–follower multi-agent systems (MASs) under switching topologies is investigated. The considered system is exposed to both the mismatched and matched disturbances in the dynamics of the leader and followers, which places higher requirements for the robustness of the control protocol. In the presence of disturbances and leader's unknown control input, an innovative distributed observer embedded with robust terms is designed firstly to estimate leader's states in finite time. Taking account of the switching topologies, a novel analysis scheme that divides the convergence process into two stages is proposed to establish the finite-time (FT) convergence of estimation errors. Then, by virtue of a constructed auxiliary variable, a FT controller with an event-triggered mechanism is put forward, in which multiple robust feedback terms are designed wisely to suppress the mismatched and matched disturbances effectively. As a result, the FT formation tracking can be achieved with saved resources, despite perturbed environments and switching topologies. Simulation examples are presented to confirm the effectiveness of the proposed algorithm. • Both the mismatched and matched disturbances are involved in the dynamics of both the leader and followers, which makes the considered problem more practical while placing a higher requirement for the robustness of the controller. • Rather than a fixed communication network, the communication topology among agents is allowed to be switching dynamically. It is noted that the coupling of the disturbances, the switching topologies and the event-triggered mechanism increases the complexity of the stability analysis and Zeno behavior exclusion. • An innovative distributed observer is proposed to estimate leader's states in finite time, even in the presence of varying networks, external disturbances, and unknown control input of the leader. • By an auxiliary variable constructed from formation errors, a novel finite-time controller with a triggering mechanism is designed, by which the desired configuration can be formed quickly while resource consumption is reduced, despite external disturbances. [ABSTRACT FROM AUTHOR]

Applying a family of mass-capacity related inequalities proved in Miao (Peking Math J 2023, ), we obtain sufficient conditions that imply the nonnegativity as well as positive lower bounds of the mass, on a class of manifolds with nonnegative scalar curvature, with or without a singularity. [ABSTRACT FROM AUTHOR]

Complex multi-vessel encounter situations are a challenging problem for ships to avoid collisions, and the International Regulations for Preventing Collision at Sea, 1972 (COLREGs) do not provide a clear delineation of multi-vessel encounter situations and the responsibility of collision avoidance (CA). Furthermore, Marine Autonomous Surface Ships (MASS), which realize autonomous navigation functions, face the problem of recognizing complex multi-ship encounter situations and the corresponding CA decisions. In this study, we adopt the velocity obstacle (VO) algorithm to visualize and identify the danger of multi-ship encounters with the own ship (OS) as the first viewpoint. Additionally, we consider the motion changes in target ships (TSs) and their possible CA behaviors as the basis of the ship's CA decision-making. According to COLREGs, a simplified method for classifying the encounter situations of multiple clustered ships is proposed, considering the coupling of collision hazards and CA responsibilities between related TSs. On this basis, the corresponding CA decisions for each classified situation are proposed, and a large number of simulation experiments are conducted based on the proposed method by considering the three-ship and four-ship encounter model in the Imazu problem as an example. The experimental results indicate that the proposed method can effectively recognize the complex multi-ship encounter situation in the Imazu problem, and it can adjust the CA measures of the OS in time according to the COLREGs and the behavior of TSs. This provides the basis and reference for MASS when facing complex multi-ship encounter situations. [ABSTRACT FROM AUTHOR]

Introduction: Lipoblastoma is a benign tumor derived from embryonic adipose tissue, accounting for 5 to 30 percent of soft tissue tumors in children. This study presents a case of a rapidly growing thigh mass in a 16-month-old child, for whom diagnosis based solely on serial clinical examinations proved challenging. Case Presentation: A 16-month-old girl presented with a lump at the posterior aspect of her left knee. Due to the rare nature of the tumor, diagnosis was delayed. Although serial clinical examinations showed no change in size, subsequent imaging revealed rapid growth, leading to a definitive diagnosis. Conclusion: In cases of fast-growing masses in children, particularly those with prominent adipose tissue imaging findings, it is crucial to consider lipoblastoma in the differential diagnosis. Advanced imaging methods should be recommended for monitoring, as serial examinations lack sufficient sensitivity in lipoblastoma follow-up. Our study underscores the limitations of serial examinations in lipoblastoma cases. Accurate diagnosis requires a combination of imaging studies and clinical evaluation. Once a definitive diagnosis is confirmed, prompt surgical removal of the tumor is advisable. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pediatric thoracic mass lesions encompass a wide range of pathogenic entities originating from various anatomical compartments within the thorax, such as the mediastinum, lung parenchyma, airways, chest wall, and pleura. While some diseases, like lymphoma, are more prevalent in children compared to adults, pediatric patients often present with a distinct array of uncommon disorders. Despite the critical need for early detection and intervention, our understanding of these lesion s frequency and distribution among pediatric populations remains inadequate, primarily due to the lack of thorough investigations in this area. OBJECTIVE: To assess the frequency and distribution of thoracic mass lesions in pediatric patients presenting in the Diagnostic imaging department of the National Institute of Child Health (NICH), a tertiary care hospital. METHODOLOGY: STUDY DESIGN: Observational, retrospective, cross-sectional study. DURATION OF STUDY: February 2022 to January 2023. SETTING: Diagnostic imaging department of the National Institute of Child Health (NICH), Karachi, Pakistan. A total of 96 children with suspected thoracic mass involving chest, pleuro-pulmonary, trachea, bronchi, and mediastinum, advised for contrast enhanced CT (CECT), with an age group from birth to 16 years, were included in the study. RESULTS: The study findings showed that out of 96 children, 49 (51.0%) were males and 47 (49.0%) were females, with an average age of 62.07 - 46.05 months. The chest findings on CECT revealed that pulmonary involvement exhibited the highest prevalence, encompassing various diseases including 46 (47.9%) cases of tumours, followed by 38 (39.6%) cases located in the mediastinum. Mediastinal lymphomas accounted for 23 (23.9%) of the most prevalent type of thoracic mass, whereas metastatic lesions involving multiple primary sources accounted for 20 (20.8%) of the cases followed by hydatid cysts 15 (15.6%). CONCLUSION: This study identified mediastinal tumors, particularly lymphomas, and pulmonary metastatic lesions as the most frequently encountered chest masses in the pediatric population. These findings highlight the critical importance of advanced imaging modalities and comprehensive radiologic evaluation in the accurate diagnosis and management of suspected chest masses. A thorough radiologic assessment is essential for guiding clinical decisions and optimizing treatment strategies. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the effect of variations in piston diameter and piston mass on the performance of a 4-stroke motorcycle. The method used is an experimental method with a quantitative approach. Data collection was carried out using the dynotest method, burret and stopwatch. The samples of this study are 3 types of pistons with different diameters where the piston mass varies to test the performance of a 4- stroke motorcycle including Torque, SFC (Specific Fuel Consumption) and BMEP (Break Mean Effective Pressure). The results of this study show that the p-value of the variation of piston diameter and mass is smaller than alpha p-value < alpha (0.05) which indicates that the variation of piston diameter and mass affects the performance of 4- stroke motorcycles. [ABSTRACT FROM AUTHOR]

In this paper, an on-line closed-loop identification of mainly mass and inertia of an under-actuated aerial vehicle, namely a quadrotor acting as an aerial manipulator, is presented. Being treated as a rigid body, only one set of eighteen- or six tri-axial linear accelerometers is used to facilitate such estimation. Force and torque disturbances acting upon the vehicle during identification are also estimated which will refine the overall estimation quality of the unknown parameters. Namely, recursive linear and nonlinear least squares methods are used to obtain initial and refined estimations, respectively. Random disturbances are introduced to the closed-loop system to ensure enough excitation of the overall system. Issues related to identifiability, stability and performance are discussed. Since the proposed method depends on general kinematical and dynamical analyses of motion, it is claimed that the presented method will be also applicable to a wider range of, mainly, aerial vehicles. [ABSTRACT FROM AUTHOR]