bluuebunny/crossref_metadata_2025 huggingface dataset:
Colonic Perforation Caused by Methicillin-Resistant Staphylococcus aureus Enteritis After Total Gastrectomy: A Case Report
Authors: Furukawa Kenei , Tsutsumi Jun , Takayama Sumio , Mashiko Hiroshi , Shiba Hiroaki , Yanaga Katsuhiko
Published: March 2015

A 68-year-old man underwent total gastrectomy and splenectomy for adenocarcinoma and low anterior resection for carcinoma in tubulo-villous adenoma of the rectum. Broad-spectrum antibiotics were administered for postoperative pancreatic fistula. Methicillin-resistant Staphylococcus aureus enteritis occurred on the 50th postoperative day and cecal perforation followed. The patient underwent construction of cecostomy with peritoneal drainage, and vancomycin was administered orally and per cecostomy for 2 weeks. The patient recovered well and was discharged at 35 days after re-operation in good general condition.
Successfully Treated Intra-Abdominal Abscess Caused by Fish Bone With Perforation of Ascending Colon: A Case Report
Authors: Yamamoto Mami , Yamamoto Kentaroh , Sasaki Takamitsu , Fukumori Daisuke , Yamamoto Fumio , Igimi Hirotsune , Yamamoto Hiroshi , Yamashita Yuichi
Published: March 2015

Ingestion of a foreign body is not uncommon, but rarely results in perforation of the gastrointestinal tract. The most common sites of perforation are reportedly the narrowest parts of the bowel, and perforation of the right side of the colon is rare. We report herein the case of a 69-year-old man who presented with an 8-week history of right upper abdominal pain. Laboratory data revealed inflammation at the first hospital visit. Computed tomography revealed a hypodense lesion containing a hyperdense foreign body in the abdomen. Intra-abdominal abscess caused by foreign body perforation was diagnosed. After administering antibiotics for 2 weeks, surgery was performed. Symptoms had resulted from perforation of the ascending colon by a fish bone.
Surgical Removal of an Intracardiac Sewing Needle in a 13-Month-Old Chinese Girl: Report of a Case
Authors: Dong Xiangyang , Zhai Bo , Li Wenjing , Cui Yazhou , Chen Zhenliang , Wang Penggao
Published: March 2015

Sewing needles, albeit rare in the case of penetrating cardiac injury, are highly lethal; especially in children, because the injury is difficult to diagnose and treat. We herein present the case of a 13-month-old girl who was injured by a sewing needle inserted in the myocardium; it is the first report of its kind from mainland China. The 13-month-old girl was referred to our hospital with a range of symptoms, including convulsions, diarrhea, and cough. Chest X-ray and echocardiogram revealed a needle located below the aortic valve, passing through the ventricular septum and aortic root. Surgical removal of the needle was performed under extracorporeal circulation. No hemorrhage or arrhythmia was seen, so the operation was ended, and the patient was discharged 8 days after the surgery. An early diagnosis and intervention proved to be lifesaving for this patient with a penetrating cardiac injury. We hope this case can provide a reference for the treatment of similar situations.
Improvement in Pulmonary Function of Chronic Obstructive Pulmonary Disease (COPD) Patients With Osteoporotic Vertebral Compression Fractures (OVCFs) After Kyphoplasty Under Local Anesthesia
Authors: Sheng Song , Zhenzhong Sun , Weimin Jiang , Yimeng Wang , Qudong Yin , Jinhui Shi
Published: March 2015

To investigate the changes in respiratory function of COPD patients with osteoporotic vertebral compression fractures (OVCFs) after kyphoplasty (KP). Pain scores, pulmonary function parameters (PFT), and local kyphotic angle (LKA) were measured in 31 older patients (25 women, 6 men) with OVCFs before, 3 days after and 3 months after kyphoplasty. The preoperative and postoperative (3 days, 3 months) PFT parameters were as follows: % pred FVC, 74.33 ± 12.35, 85.23.8 ± 13.23, and 84.86 ± 14.01; % pred FEV1, 60.23 ± 11.2, 60.02 ± 11.90, and 60.78 ± 12.70; FEV1/FVC ratio (%), 68.22 ± 16.74, 59.56 ± 13.23, and 60.77 ±12.28, % pred MVV 52.46 ± 14.37, 55.23 ± 15.68, and 62.12 ± 14.48, respectively. The preoperative mean VAS score was 8.01 ± 1.41 and significantly decreased to 2.52 ± 0.89 and 2.34 ± 0.78 at 3 days, 3 months after kyphoplasty, respectively. The preoperative local kyphotic angle degree was 21.96 ± 5.75°, significantly decreased to 13.48 ± 6.12° 3 days after KP, and maintained 3 month after KP. The decrease in the VAS scores correlated with the PFT parameters; however, there were no significant correlations between the PFT parameters and the LKA, the VAS scores and the LKA. Kyphoplasty under local anesthesia is a safety treatment for the COPD patients with OVCFS, and is able to improve the lung function impaired by OVCFs.
Intravenous Lidocaine for Effective Pain Relief After a Laparoscopic Colectomy: A Prospective, Randomized, Double-Blind, Placebo-Controlled Study
Authors: Ahn EunJin , Kang Hyun , Choi Geun Joo , Park Yong Hee , Yang So Young , Kim Beom Gyu , Choi Seung Won
Published: March 2015

A perioperative intravenous lidocaine infusion has been reported to decrease postoperative pain. The goal of this study was to evaluate the effectiveness of intravenous lidocaine in reducing postoperative pain for laparoscopic colectomy patients. Fifty-five patients scheduled for an elective laparoscopic colectomy were randomly assigned to 2 groups. Group L received an intravenous bolus injection of lidocaine 1.5 mg/kg before intubation, followed by 2 mg/kg/h continuous infusion during the operation. Group C received the same dosage of saline at the same time. Postoperative pain was assessed at 2, 4, 8, 12, 24, and 48 hours after surgery by using the visual analog scale (VAS). Fentanyl consumption by patient-controlled plus investigator-controlled rescue administration and the total number of button pushes were measured at 2, 4, 8, 12, 24, and 48 hours after surgery. In addition, C-reactive protein (CRP) levels were checked on the operation day and postoperative days 1, 2, 3, and 5. VAS scores were significantly lower in group L than group C until 24 hours after surgery. Fentanyl consumption was lower in group L than group C until 12 hours after surgery. Moreover, additional fentanyl injections and the total number of button pushes appeared to be lower in group L than group C (P < 0.05). The CRP level tended to be lower in group L than group C, especially on postoperative day1 and 2 and appeared to be statistically significant. The satisfaction score was higher in group L than group C (P = 0.024). Intravenous lidocaine infusion during an operation reduces pain after a laparoscopic colectomy.
Immunoglobulin G4–Related Sclerosing Cholangitis Mimicking Hilar Cholangiocarcinoma Diagnosed With Following Bile Duct Resection: Report of a Case
Authors: Miki Atsushi , Sakuma Yasunaru , Ohzawa Hideyuki , Sanada Yukihiro , Sasanuma Hideki , Lefor Alan T. , Sata Naohiro , Yasuda Yoshikazu
Published: March 2015

We report a rare case of immunoglobulin G4 (IgG4)–related sclerosing cholangitis without other organ involvement. A 69-year-old-man was referred for the evaluation of jaundice. Computed tomography revealed thickening of the bile duct wall, compressing the right portal vein. Endoscopic retrograde cholangiopancreatography showed a lesion extending from the proximal confluence of the common bile duct to the left and right hepatic ducts. Intraductal ultrasonography showed a bile duct mass invading the portal vein. Hilar bile duct cancer was initially diagnosed and percutaneous transhepatic portal vein embolization was performed, preceding a planned right hepatectomy. Strictures persisted despite steroid therapy. Therefore, partial resection of the common bile duct following choledochojejunostomy was performed. Histologic examination showed diffuse and severe lymphoplasmacytic infiltration, and abundant plasma cells, which stained positive for anti-IgG4 antibody. The final diagnosis was IgG4 sclerosing cholangitis. Types 3 and 4 IgG4 sclerosing cholangitis remains a challenge to differentiate from cholangiocarcinoma. A histopathologic diagnosis obtained with a less invasive approach avoided unnecessary hepatectomy.
How Better Health Strategies Could Reduce Juvenile Crime
Authors: Butler Stuart M.
Published: August 2024

This JAMA Forum discusses health strategies that could be used to reduce juvenile crime, including identifying and treating trauma with behavioral health, rethinking the punishment approach, and incorporating other methods to overcome current challenges.
Thiazide Dose, Urine Calcium, and Symptomatic Kidney Stone Events
Authors: Hsi Ryan S. , Yan Phyllis L. , Maalouf Naim M. , Best Sara L. , Asplin John R. , Shahinian Vahakn , Hollingsworth John M.
Published: August 2024

This cohort study examines the association between thiazide dose and urine calcium reduction and correlates urine calcium changes with the occurrence of symptomatic kidney stone events.
A wide voltage range non‐isolated continuous input buck‐boost converter for optimal green energy harvesting in LED lighting systems
Authors: Kanithi Ashok Kumar , B L Narasimharaju
Published: August 2024

This article introduces a wide input range buck‐boost Light Emitting Diode (LED) driver designed for industrial and street lighting applications. The driver characterized by a continuous input current with less ripple and common ground between input and output featuring non‐inverting voltage at the output, suitable for green energy sources. The proposed topology achieves a high voltage conversion ratio which is a blend of quasi‐Z source boosting followed by conventional buck with enhanced step‐down voltage capability. Furthermore, the driver maintains a constant voltage at the load terminal for diverse source voltage variations by adapting the inherent buck‐boost nature. Also, the driver operates with low duty ratio results in lower voltage, current stresses and conduction losses. The steady state and design analysis of the proposed LED driver is carried out for an input voltage range from 24 to 96 V. An experimental prototype of 200 W/71 V LED driver is validated in the laboratory for wide input voltage. There is a high concordance exists between the theoretical analysis and experimental results of the proposed topology.
Implications of Developmental 17‐OHPC Exposure on the Mesocorticolimbic Serotonergic and Dopaminergic Pathways and Adolescent Mood–Related Behavior in Rats
Authors: Graney Paige L. , Sarno Evelyn L. , Miller Jessie E. , Wagner Christine K.
Published: August 2024

The synthetic progestin, 17‐α‐hydroxyprogesterone caproate (17‐OHPC), is administered to pregnant individuals at risk for recurrent preterm birth during a critical period of fetal mesocorticolimbic serotonergic and dopaminergic pathway development. These pathways play an important role in regulating cognitive behaviors later in life. Despite this, there has been very little research regarding the potential long‐term effects of 17‐OHPC on the behavioral and neural development of exposed children. In rodents, developmental exposure to 17‐OHPC disrupts serotonergic and dopaminergic innervation of the medial prefrontal cortex and impairs decision‐making in complex cognitive tasks in adulthood. The present study tested the hypothesis that developmental exposure to 17‐OHPC similarly disrupts the development of serotonergic and dopaminergic pathways within limbic targets and subsequent mood‐related behaviors. Developmental 17‐OHPC exposure significantly increased the density of serotonin transporter–IR fibers in CA1, CA2/3, and the suprapyramidal blade of dentate gyrus in hippocampus and significantly reduced the density of TH‐IR fibers within the nucleus accumbens shell in males but had no effect in females during adolescence. Irregular microglia activational phenotype and number were also observed in the hippocampus of 17‐OHPC‐exposed males. Developmental 17‐OHPC reduced the latency to immobility in males in the forced swim test but did not affect sucrose consumption in a sucrose preference test. These findings suggest that 17‐OHPC exerts sex‐specific effects on the development of mesocorticolimbic pathways and mood‐related behavior in adolescence and highlight the need to investigate effects in adolescent children.
Transthyretin amyloid cardiomyopathy: Literature review and red‐flag symptom clusters for each cardiology specialty
Authors: Izumiya Yasuhiro , Kubo Toru , Endo Jin , Takashio Seiji , Minamisawa Masatoshi , Hamada Jun , Ishii Tomonori , Abe Hajime , Konishi Hiroaki , Tsujita Kenichi
Published: August 2024

Wild‐type transthyretin amyloid cardiomyopathy (ATTRwt‐CM) is a progressive and infiltrative cardiac disorder that may cause fatal consequences if left untreated. The estimated survival time from diagnosis is approximately 3–6 years. Because of the non‐specificity of initial symptom manifestation and insufficient awareness among treating physicians, approximately one‐third of patients with ATTRwt‐CM are initially misdiagnosed with other cardiac diseases. Although heart failure (HF) is the most common initial manifestation of ATTRwt‐CM, observed in nearly 70% of affected patients, patients may also present with other cardiologic symptoms, such as atrial fibrillation (AF) and aortic stenosis (AS). This non‐specific and diverse nature of the initial ATTRwt‐CM presentation indicates that various cardiology subspecialties are involved in patient diagnosis and management. Standard guideline‐directed pharmacological treatment for HF is not recommended for patients with ATTRwt‐CM because of its limited effectiveness. However, no established algorithms are available regarding HF management in this patient population. This literature review provides an overview of the red flags for ATTRwt‐CM and research findings regarding HF management in this patient population. In addition to commonly recognized red flags for ATTRwt‐CM (e.g., HF, AF and severe AS), published literature identified potential red flags such as coronary microvascular dysfunction. For HF management in patients with ATTRwt‐CM, the use of mineralocorticoid receptor antagonists (MRAs) was reported as a well‐tolerated option associated with a low discontinuation rate and reduced mortality. Although there is no concrete evidence for recommendations against sodium‐glucose cotransporter 2 inhibitor (SGLT2i) administration, research supporting its use is limited to small‐scale studies. Robust evidence is lacking for AF ablation, implantable cardioverter‐defibrillators and cardiac resynchronization therapy. Based on the published findings and our clinical experience as Japanese ATTRwt‐CM experts, red‐flag symptom clusters for each cardiology specialty (HF, arrhythmia and ischaemia/structural heart disease) and a treatment scheme for HF management are presented. As this research area remains at an exploratory stage, our observations would require further discussion among experts worldwide.
Chemical evidence for separating Aspleniaceae from Athyriaceae: Free amino acids
Authors: Lal S. D.
Published: August 2024

Asplenium L. and Athyrium L. vary in their absolute and relative contents of amino acids and amides. These, in addition to the morphological and anatomical differences, help to separate Aspleniaceae from Athyriaceae.
Ein neues Guttiferen‐Holz aus dem Tertiär von Java, Calophylloxylon intermedium sp. nov.
Authors: Müller‐Stoll Wolfgang R. , Mädel‐Angeliewa Erika
Published: August 2024

Aus dem Mio‐Pliozän von West‐Juva wird ein fossiles Cuttiferen‐Holz beschrieben, das dem rezenten Calophyllum spectabile Willd, nahesteht, aber auch zu Mesua ferrea L. gewisse Beziehungen hat : Calophylloxylon intermedium sp. nov. Die bisher beschriebenen fossilen Guttiferen‐Hölzer werden kritisch betrachtet; sie gehören zu den Gattungen Calophylloxylon Lakhantal & Awasthi, Kayeoxylon Chowdhury & Tandan, Mesuoxylon Lakhanpal & Awasthi und Symphonioxylon Chiarugi (Syn. Guttiferoxylon Kräusel). Ihre Fundorte liegen innerhalb des Verbreitungsgebietes der rezenten Vergleichsgattungen; aus dem Tertiär von Österreich und Algerien beschriebene angebliche Guttiferen‐Hölzer sind keine sicheren Belege für das Vorkommen der Familie.
Statistical Properties of GinSE and Elliptic GinSE
Authors: Byun Sung-Soo , Forrester Peter J.
Published: August 2024

Eigenvalues of GinSE matrices occur in complex conjugate pairs as for complex GinOE eigenvalues, but now with zero probability of an eigenvalue being real. Also in common with complex GinOE eigenvalues is that the GinSE eigenvalues form a Pfaffian point process, and that their PDF admits a Coulomb gas interpretation with image terms. While the determination of the required skew-orthogonal polynomials is straightforward, the particular form gives a new challenge in relation to analysing the various scaling limits. This is overcome by making use of a certain inhomogeneous partial differential equation satisfied by the pre-kernel. Such an approach carries over to the analysis of a weakly non-Hermitian regime. Also contained in this chapter is the large N analysis of the partition function and gap probability associated with GinSE eigenvalues, and results relating to the singular values and eigenvectors. Furthermore, a study is undertaken of an elliptic generalisation, which interpolates between GinSE and Hermitian GSE matrices.
Individualrechte in der KI-Verordnung
Authors: Hornung Gerrit
Published: August 2024

Während der Kommissionsentwurf zur KI-VO die Rechtspositionen der betroffenen Personen praktisch komplett ausblendete, enthält der verabschiedete Normtext einen deutlich stärkeren Fokus in dieser Richtung und führt insbesondere zwei neue Betroffenenrechte ein. Angesichts der Grundrechtsrelevanz vieler KI-Systeme ist dies zu begrüßen; die konkrete Umsetzung führt allerdings zu neuen Fragen sowohl in der Binnensystematik der KI-VO als auch im Verhältnis zur DS-GVO.
Wirkung von Webshop-Gütesiegeln
Authors: Aldag Lukas , Hennig Anne , Volkamer Melanie
Published: August 2024

Gütesiegel finden sich auf vielen, vor allem kleineren Webshop-Seiten. Die bisherige Forschung hat sich darauf konzentriert, wie die Anzeige eines Gütesiegels auf der Webseite eines Webshops das Kaufverhalten der Verbraucher beeinflusst. Offen ist, was Kaufinteressenten, die grundsätzlich auf das Vorhandensein von Gütesiegeln achten, über die Aussagekraft eines Gütesiegels und über die Gefahr wissen, dass auch Betrüger solche Gütesiegel-Symbole unberechtigt auf ihren betrügerischen Webshop-Seiten einbinden können.
Assessment of Hungarian large cities readiness in adopting electric bike sharing system
Authors: Jaber Ahmed , Csonka Bálint
Published: August 2024

This study explores the readiness of eight large Hungarian cities to adopt electric bike sharing systems as a sustainable transportation mode. By assessing 25 indicators related to infrastructure, safety, demographics, legislation, and transportation systems, we comprehensively understand each city's current situation and readiness level. By engaging experts, we derived weighted scores for key indicators to provide a comprehensive analysis of each city's potential. The results reveal varied readiness across cities, offering targeted insights for policymakers to enhance urban mobility sustainably. Our analysis reveals that certain cities, such as Budapest and Gyor, are better prepared for sustainable transportation than others. However, every city has positive and negative aspects that must be considered. Establishing infrastructure for cycling and connectivity to public transportation systems should be prioritized in Hungarian cities. Additionally, safety action plans should be implemented to address road safety concerns. Promoting cycling culture and electric vehicles is also essential to encourage the adoption of sustainable transportation modes. The findings of this research offer valuable insights to policymakers, urban planners, and researchers interested in promoting sustainable mobility.
Climate Model Simulates Unusually High Heat over the Southern Ocean
Authors: Stanley Sarah
Published: August 2024

U.K. researchers compare HadGEM3-GC3.1 simulations of near-surface air temperatures with those from other state-of-the-art models.
The STL-ARIMA approach for seasonal time series forecast: A preliminary study
Authors: Lem Kong Hoong
Published: August 2024

STL, which stands for Seasonal and Trend decomposition using Loess, is a technique used to decompose a time series into its underlying components: trend, seasonal, and remainder. In this study, STL has been combined with the AutoRegressive Integrated Moving Average, ARIMA model in an effort to improve the forecast performance on seasonal time series. The proposed algorithm used STL decomposition to isolate the trend, seasonal and remainder components within the time series data. ARIMA or SARIMA models were then independently fitted to each component to capture their dynamics. Finally, the component-wise forecasts were aggregated to generate the final overall forecast. Forecast performance was compared with the SARIMA model using metrics such as MAE, RMSE and MAPE. Based on a preliminary case study by using atmospheric carbon dioxide concentration data from Mauna Loa, Hawaii, the findings suggest that the proposed algorithm offers a viable alternative for improving forecast performance in seasonal data.
Danish fire insurance data: A review and additional analysis
Authors: Shongwe Sandile Charles , Marambakuyana Walena Anesu
Published: August 2024

The Danish fire insurance data is one of the most recognised and well-known datasets in the empirical insurance claims literature. This dataset is used in many textbooks and articles to illustrate the analysis of fire insurance claims, more specifically in the application of heavy-tailed loss distributions and extreme value theory. In this paper, we provide a short review of publications that used the Danish fire insurance data and conduct an additional analysis. Our additional analysis on the Danish fire insurance data involves investigating the: (i) modality issue using appropriate statistical tests and software, (ii) k-means clustering pattern using different techniques, (iii) effect of using a splicing model on the data, and (iv) differences in results that we obtained as compared to what other cited researchers reported in their earlier publications. In short, the objective of this paper is to highlight the importance of the Danish fire claims dataset by showcasing different models where it has been used to verify certain hypotheses in the empirical actuarial field. Additional analyses are also conducted to illustrate its dense usefulness in the actuarial and extremes field, where real-life datasets are scarce because they are often subjected to a lot of proprietary and privacy laws.
An Economic Production Quantity inventory model with a circular economy indicator operating in two markets
Authors: Lee Soo Lin , Yeo Ivan , Chin Wan Yoke
Published: August 2024

A sustainable inventory system seeks to enhance production profits and minimize environmental impact. This study introduces an Economic Production Quantity (EPQ) model incorporating dual-market demand, recoverable items, external procurement, and variable item return rates, along with a circular economy indicator. Two scenarios are examined during the concurrent production and repair processes, and a model is devised to maximize the total profit per unit time (TPUT). In the first scenario, there is a sufficient or surplus quantity of moderate-quality return items available for repair. In the second scenario, there is an insufficient quantity of moderate-quality return items for repair, necessitating additional procurement from an external supplier. Items repaired from both scenarios will be marketed in the secondary market. Additionally, both scenarios involve the sale of repaired high-quality return items in the primary market. In the absence of a sufficient quantity of high-quality return items, new production items are anticipated to meet the remaining demand of the primary market. The proposed models are tested through numerical examples, and a numerical sensitivity analysis is conducted to explore how dual-market operations affect the total profit per unit time.
Probabilistic Soft Set Theory for Decision-Making in Choosing Korean Dramas
Authors: Cahyati Era Setya , Rosadi Dedi
Published: August 2024

Decision-making involves subjective elements influenced by individual preferences and uncertainties. A flexible framework to handle these complications is offered by probabilistic soft set theory. Probabilistic soft sets is an extension of soft set. This mathematical framework deals with ambiguity and uncertainty in the process of making decisions. Recent results had been devoted for development the theoretical aspect of the method and only a little study has been done for the usage of the theory for decision-making. In this study, we provide two algorithms as the application of the probabilistic soft set theory for decision-making. For real application we use the algorithms to determine the Korean dramas to be watched. To apply this method, a set of Korean drama titles, which has release dates from 1 July 2023 until 31 December 2023, has been collected. Subsequently, using this method, the data is processed and analyzed to determine the chosen drama.
Covariate balancing strategy for single and multiple exposures with interaction
Authors: Jhan Yan-ni , Dinh Thai Son , Lian Ie-bin
Published: August 2024

Balancing the distribution of covariates (Z) among exposure levels is a crucial step for establishing causality between the exposure and the outcome in observational studies. Standard approaches utilizing propensity score typically focus on a single exposure, yet it is not uncommon for the exposure to interact with other variables on the outcome. Ignoring such interactions and applying standard balancing procedures solely on a single exposure can lead to significant bias. For instance, consider the Georgia Capital Charging and Sentencing Study, which sought to examine whether the race of the defendant and the race of the victim influenced the severity or length of the sentence (Y). In such a study, there are two exposures of interest on the outcome with significant interaction. Analysing each exposure separately may produce biased results. Base on the simulation results we suggest to use covariate-partition strategy for single-exposure scenario and all-covariate strategy for multiple-exposure scenario.
Rotorcraft design influences noise impacts of multiple vehicles in flight
Authors: Johnson-Groh Mara
Published: August 2024

If electric rotorcraft are to be our commuter vehicles of the future, they must overcome acoustic limitations.
A menagerie of Martian auroras
Authors: Deighan Justin
Published: August 2024

The red planet’s auroral activity stems from processes that are not seen on Earth.
The evolution of autonomy from two cooperative specialists in fluctuating environments
Authors: Chen Xiaoli , Wang Miaoxiao , Luo Laipeng , Liu Xiaonan , An Liyun , Nie Yong , Wu Xiao-Lei
Published: August 2024

From microbes to humans, organisms perform numerous tasks for their survival, including food acquisition, migration, and reproduction. A complex biological task can be performed by either an autonomous organism or by cooperation among several specialized organisms. However, it remains unclear how autonomy and cooperation evolutionarily switch. Specifically, it remains unclear whether and how cooperative specialists can repair deleted genes through direct genetic exchange, thereby regaining metabolic autonomy. Here, we address this question by experimentally evolving a mutualistic microbial consortium composed of two specialists that cooperatively degrade naphthalene. We observed that autonomous genotypes capable of performing the entire naphthalene degradation pathway evolved from two cooperative specialists and dominated the community. This evolutionary transition was driven by the horizontal gene transfer (HGT) between the two specialists. However, this evolution was exclusively observed in the fluctuating environment alternately supplied with naphthalene and pyruvate, where mutualism and competition between the two specialists alternated. The naphthalene-supplied environment exerted selective pressure that favors the expansion of autonomous genotypes. The pyruvate-supplied environment promoted the coexistence and cell density of the cooperative specialists, thereby increasing the likelihood of HGT. Using a mathematical model, we quantitatively demonstrate that environmental fluctuations facilitate the evolution of autonomy through HGT when the relative growth rate and carrying capacity of the cooperative specialists allow enhanced coexistence and higher cell density in the competitive environment. Together, our results demonstrate that cooperative specialists can repair deleted genes through a direct genetic exchange under specific conditions, thereby regaining metabolic autonomy.
Correlated variability and its attentional modulation depend on anatomical connectivity
Authors: Shah Shraddha , Hembrook-Short Jacqueline , Mock Vanessa , Briggs Farran
Published: August 2024

Visual cortical neurons show variability in their responses to repeated presentations of a stimulus and a portion of this variability is shared across neurons. Attention may enhance visual perception by reducing shared spiking variability. However, shared variability and its attentional modulation are not consistent within or across cortical areas, and depend on additional factors such as neuronal type. A critical factor that has not been tested is actual anatomical connectivity. We measured spike count correlations among pairs of simultaneously recorded neurons in the primary visual cortex (V1) for which anatomical connectivity was inferred from spiking cross-correlations. Neurons were recorded in monkeys performing a contrast-change discrimination task requiring covert shifts in visual spatial attention. Accordingly, spike count correlations were compared across trials in which attention was directed toward or away from the visual stimulus overlapping recorded neuronal receptive fields. Consistent with prior findings, attention did not significantly alter spike count correlations among random pairings of unconnected V1 neurons. However, V1 neurons connected via excitatory synapses showed a significant reduction in spike count correlations with attention. Interestingly, V1 neurons connected via inhibitory synapses demonstrated high spike count correlations overall that were not modulated by attention. Correlated variability in excitatory circuits also depended upon neuronal tuning for contrast, the task-relevant stimulus feature. These results indicate that shared variability depends on the type of connectivity in neuronal circuits. Also, attention significantly reduces shared variability in excitatory circuits, even when attention effects on randomly sampled neurons within the same area are weak.
Schlank orchestrates insect developmental transition by switching H3K27 acetylation to trimethylation in the prothoracic gland
Authors: Yuan Dongqin , Zhang Xing , Yang Yan , Wei Ling , Li Hao , Zhao Tujing , Guo Mengge , Li Zheng , Huang Zhu , Wang Min , Dai Zongcai , Li Peixin , Xia Qingyou , Qian Wenliang , Cheng Daojun
Published: August 2024

Insect developmental transitions are precisely coordinated by ecdysone and juvenile hormone (JH). We previously revealed that accumulated H3K27 trimethylation (H3K27me3) at the locus encoding JH signal transducer Hairy is involved in the larval–pupal transition in insects, but the underlying mechanism remains to be fully defined. Here, we show in
Drosophila
and
Bombyx
that Rpd3-mediated H3K27 deacetylation in the prothoracic gland during the last larval instar promotes ecdysone biosynthesis and the larval–pupal transition by enabling H3K27me3 accumulation at the
Hairy
locus to induce its transcriptional repression. Importantly, we find that the homeodomain transcription factor Schlank acts to switch active H3K27 acetylation (H3K27ac) to repressive H3K27me3 at the
Hairy
locus by directly binding to the
Hairy
promoter and then recruiting the histone deacetylase Rpd3 and the histone methyltransferase PRC2 component Su(z)12 through physical interactions. Moreover, Schlank inhibits
Hairy
transcription to facilitate the larval–pupal transition, and the Schlank signaling cascade is suppressed by JH but regulated in a positive feedback manner by ecdysone. Together, our data uncover that Schlank mediates epigenetic reprogramming of H3K27 modifications in hormone actions during insect developmental transition.
Atomic resolution map of the solvent interactions driving SOD1 unfolding in CAPRIN1 condensates
Authors: Ahmed Rashik , Liang Mingyang , Hudson Rhea P. , Rangadurai Atul K. , Huang Shuya Kate , Forman-Kay Julie D. , Kay Lewis E.
Published: August 2024

Biomolecules can be sequestered into membrane-less compartments, referred to as biomolecular condensates. Experimental and computational methods have helped define the physical-chemical properties of condensates. Less is known about how the high macromolecule concentrations in condensed phases contribute “solvent” interactions that can remodel the free-energy landscape of other condensate-resident proteins, altering thermally accessible conformations and, in turn, modulating function. Here, we use solution NMR spectroscopy to obtain atomic resolution insights into the interactions between the immature form of superoxide dismutase 1 (SOD1), which can mislocalize and aggregate in stress granules, and the RNA-binding protein CAPRIN1, a component of stress granules. NMR studies of CAPRIN1:SOD1 interactions, focused on both unfolded and folded SOD1 states in mixed phase and demixed CAPRIN1-based condensates, establish that CAPRIN1 shifts the SOD1 folding equilibrium toward the unfolded state through preferential interactions with the unfolded ensemble, with little change to the structure of the folded conformation. Key contacts between CAPRIN1 and the H80-H120 region of unfolded SOD1 are identified, as well as SOD1 interaction sites near both the arginine-rich and aromatic-rich regions of CAPRIN1. Unfolding of immature SOD1 in the CAPRIN1 condensed phase is shown to be coupled to aggregation, while a more stable zinc-bound, dimeric form of SOD1 is less susceptible to unfolding when solvated by CAPRIN1. Our work underscores the impact of the condensate solvent environment on the conformational states of resident proteins and supports the hypothesis that ALS mutations that decrease metal binding or dimerization function as drivers of aggregation in condensates.
Investigation on gain-managed nonlinearity in Mamyshev oscillators
Authors: Lu Sihua , Guo Wei , Zhang Baofu , He Qiurun , Jiao Zhongxing , Lai Tianshu
Published: August 2024

Mamyshev oscillators and gain-managed nonlinear (GMN) amplifiers have the capability to generate high-power sub-50 fs pulses, but their close relationship has not been systematically investigated. In this paper, we numerically study the influence of gain-managed nonlinearity on the laser evolution and output characteristics of the Mamyshev oscillator. The impact of the gain fibre length, as well as the central wavelength and bandwidth of spectral filters on GMN evolution in the laser are investigated. The results indicate that optimizing these cavity parameters can lead to the GMN evolution, which can improve the output peak power by 1.5–4 times in Mamyshev oscillators.
Optical manipulations without light forces: deep superlattice for trapping and rotation of impurity particles in a buffer gas
Authors: Krasnov I V
Published: August 2024

We propose a scheme to obtain a deep optical superlattice (OSL) for resonant impurity particles in a buffer gas. In contrast to the well-known traditional methods of forming optical lattices (supelattices) that are based on the gradient force of radiation pressure, the presented scheme is based on the effect of a light induced drift (LID) in interfering light waves. The principle of its operation is based on the conception of so-called rectified forces induced by interfering bichromatic optical fields, which was developed earlier in the theory of resonant radiation-pressure forces. In the scheme under consideration, a deep OSL (with a period much larger than the optical wavelength) is formed due to the action of the effective rectified force on atomic particles which is proportional to the difference between the frequencies of transport collisions of excited and unexcited particles with buffer gas atoms.
Adaptive remaining useful life prediction method for aircraft engines under variable operational conditions based on multi-channel transformer
Authors: Cao Jinshan
Published: August 2024

Aiming at the problem of degradation trend being covered under time-varying operating conditions and insufficient generalization ability of prediction models, which leads to reduced predictive performance, a domain adaptive method (MC-TraMMDNet) combining improved multi-channel transformer and Maximum Mean Discrepancy (MMD) is proposed for end-to-end prediction of remaining useful life (RUL) of aircraft engines. Firstly, the monitoring data of variable operating conditions are clustered and normalized at the same lifespan scale based on the fault state data. Secondly, corresponding transformer encoders are established for each operating condition, and degradation information is comprehensively extracted for each operating condition through a multi-head self-attention mechanism and multi-channel convolutional network. In addition, to enhance the generalization of the model, the maximum mean difference heterogeneous domain adaptive layer is used to extract domain invariant features. Next, a multi-layer perceptron model is utilized for forecasting the remaining useful lifespan of aircraft engines in diverse operational environments. Finally, validation is carried out on the publicly available dataset C-MAPSS. In comparison to other methods, the results demonstrate that this method excels in both RMSE and Score. The evaluation indicators have decreased by about 9% and 35% respectively.
Design and implementation of 3D printed twin-propeller aeronautical model
Authors: Jiang Yangjiao , Duan Tianyu , Jiang Haofei , Chen Quan , Chen Yong
Published: August 2024

Based on the application requirements of 3D printing technology in aviation models, a twin-propeller aviation model manufactured by 3D printing technology was designed and realized. The twin-propeller model was designed using 3D modeling software, and 3D printing technology was used for physical fabrication. The detailed design and structural optimization of the model ensures that it achieves the best performance in terms of aerodynamics, stability, and propulsion efficiency. Through the production and assembly of 3D-printed parts, a scaled-down physical prototype was successfully made, and flight tests were simulated in the field. The experimental flight results show that the model has good flight stability and efficient propulsion ability. In addition, the application of 3D printing technology has also significantly shortened the manufacturing cycle of the model and improved the accuracy and consistency of manufacturing. The great potential of advanced manufacturing technology in the field of aerospace models has been demonstrated. This method not only improves the performance and manufacturing efficiency of the model but also provides a new idea and technical path for the design and manufacture of future aerospace vehicles.
Overall parameter design method and sensitivity analysis for solar aircraft
Authors: Wang Yuchen , Sun Kangwen , Liu Siyu , Tian Yongliang , Liang Haoquan
Published: August 2024

This paper establishes the overall parameter model for solar aircraft based on energy balance constraints and mass balance constraints. On this basis, a method for the overall parameter design considering the feasible design domain is proposed, with the aircraft’s total mass and wing area as optimization objectives. Sensitivity analysis and scenario study of the optimal configuration of solar-powered aircraft under various general parameters during the design process is conducted. Finally, a design scheme is introduced and compared with prototype data. The results verify the practical applicability of the scheme. The method proposed in this article can provide a reference for the conceptual design stage of solar aircraft.
Enhancing spool valve sealing performance with an annular groove
Authors: Xia Haijie , Zhang Guoqing
Published: August 2024

Spool valves in aviation engine fuel control devices have a vital effect on fuel supply to ensure the engine runs properly. Therefore, the sealing performance of valve components is particularly important for the overall performance and safety of the system. A more accurate fit between the valve body and the moving parts is needed to enhance the sealing performance of the spool valve. However, leaks still exist even with more precise manufacturing due to various factors. This paper proposes a novel design, an annular groove, which differs from previous methods and is described by the dimensionless design parameters of the spool valve. This paper concludes that dimensionless parameters depth h/d and relative position l/L of the annular groove have little influence on the leakage amount. Still, the width w/d has an obvious influence on that. The lower the w/d is, the smaller the leakage is, and the greater the vice versa. According to the simulation calculation, this is mainly because w is easier to induce the reverse pressure gradient of the flow field, leading to the formation of vortices within the annular groove and a consequent reduction in induced velocity, thereby minimizing leakage.
Impact of leading edge slat on stall performance of multi-element airfoils
Authors: Zhang Daqian , Shi Xionglin , Chen Zhongming
Published: August 2024

To ensure the safe takeoff and landing of large commercial aircraft, complex lift augmentation devices have been widely applied. Despite this, even at steep attack angles, leading edge slats on certain multi-element wings can still undergo airflow detachment. This leads to an enlarged wake area behind the slat, diminished airflow circulation around the wing segment, and a decrease in the lift generated by the airfoil. Consequently, this induces intricate air currents between the slat and the main section of the wing, as well as between the main wing and the trailing edge flap, potentially culminating in wing stalls and mishaps. To enhance the takeoff and landing capabilities of multi-element airfoils, the standard multi-element airfoil, 30P30N, was chosen for investigation. By applying the finite volume Reynolds-averaged Navier-Stokes (RANS) approach and utilizing the Fluent module within ANSYS Workbench, the impact of slat position and dimension at the leading edge on the stall behavior of the airfoil was examined. The findings indicate that choosing suitable positions and dimensions for leading-edge slats can efficiently postpone the start of airflow detachment over the wing sections, curb the spread of the airfoil’s wake, and diminish the detachment and blending of slat airflow with the downstream wing section’s boundary layer flow. This substantially improves the aircraft’s aerodynamic efficiency during low-speed takeoffs and landings.
Study on the hypersonic separation of the parallel configuration of the combined cycle two-stage orbit vehicle
Authors: Duan Yuxuan , Xu Zhendong , Liu Zhao , Li Suhang , Lv Zhixin
Published: August 2024

The hypersonic vehicle is an important development direction of the future aerospace technology. An important role of this type of aircraft is as a carrier-level aircraft to send the orbit-level aircraft to a specified altitude and a specified speed and then return separately. Due to the high speed during separation, the serious aerodynamic load, and the severe wave system interference between the two aircraft, the safe separation of the aircraft is more challenging. In this paper, based on the Rocket based Combined Cycle (RBCC) two-stage orbiting carrier system, the research is conducted on the separation of the carrier based on the lift body configuration and upper stage rocket in the atmosphere at hypersonic conditions.
A real-time energy management method for APTMS based on FCM-BP neural network
Authors: Fu Jiecheng , Zhang Jingyang , Zheng Fengying
Published: August 2024

In order to improve the real-time performance of APTMS energy management and ensure fuel economy, a real-time energy management method based on a fuzzy C-means clustering algorithm combined with a BP neural network is proposed. Firstly, the coupling simulation model of APTMS and engine energy efficiency is established. The multi-source energy configuration parameters are obtained by using a particle swarm optimization algorithm combined with an off-line simulation of various flight conditions, and the energy management rule sample library is formed. The fuzzy C-means clustering algorithm is used to classify the energy management rule sample library, and some samples are extracted based on the ranking of membership degrees for the training of the neural network. Finally, the trained neural network predictor is used to predict multi-source energy parameters according to real-time flight conditions. The simulation results show that the FCM-BP neural network method can approach the effect of off-line optimization of PSO and achieve good multi-source energy parameter prediction. The maximum prediction error is 1.91 %, and the FCM-BP neural network method shortens the simulation time by 97.31 %, which has the ability of an online application.
A method of satellite constellation observation based on J2 perturbation application
Authors: Wang Biao , Song Xumin , Li Yiyong , Wang Weilin
Published: August 2024

In view of the problem of a large number of satellite observations, a method of satellite constellation observation by retrograde orbital spacecraft is proposed by applying the drift of J2
perturbation on the RAAN of the spacecraft. Firstly, the basic configuration and spatial position relationship of the satellite constellation are analyzed. Secondly, the influence of the J2
perturbation on the RAAN of the spacecraft is analyzed. Finally, by using the effect of J2
perturbation, the observation methods of single and multiple retrograde orbit spacecraft for satellite constellation are analyzed, respectively. The simulation results demonstrate the feasibility of this method of satellite constellation based on J2
perturbation application.
A Fast solution method for end-effector force extremum in redundant cable-driven parallel robots
Authors: Luo Yanhao
Published: August 2024

For the problem of quickly obtaining the range of load forces in a specific direction at the end-effector of an eight-cable, six-degree-of-freedom redundantly driven cable-parallel robot, a method based on geometric approaches in six-dimensional space for judging the extremum of the end-effector platform force is proposed, which involves shifting the convex hull formed by six-dimensional hyperplanes and intersecting it with a line or a two-dimensional section to determine the extremum of the feasible force of the end-effector, enabling rapid judgment of the force range that the platform can generate in any given orientation. Using an eight-cable, six-degree-of-freedom mechanism as an example, the proposed method establishes an end-effector position-acceleration image and utilizes position-acceleration curves to plan motion trajectories. The computed trajectory of cable forces satisfies the imposed constraints.