A. Babuponnusami, K. Muthukumar
Hasil untuk "Technology (General)"
Menampilkan 20 dari ~22221205 hasil · dari DOAJ, arXiv, Semantic Scholar, CrossRef
G. Pilbratt, J. Riedinger, T. Passvogel et al.
Herschel was launched on 14 May 2009, and is now an operational ESA space observatory o ering unprecedented observational capabilities in the far-infrared and submillimetre spectral range 55 671 m. Herschel carries a 3.5 metre diameter passively cooled Cassegrain telescope, which is the largest of its kind and utilises a novel silicon carbide technology. The science payload comprises three instruments: two direct detection cameras/medium resolution spectrometers, PACS and SPIRE, and a very high-resolution heterodyne spectrometer, HIFI, whose focal plane units are housed inside a superfluid helium cryostat. Herschel is an observatory facility operated in partnership among ESA, the instrument consortia, and NASA. The mission lifetime is determined by the cryostat hold time. Nominally approximately 20,000 hours will be available for astronomy, 32% is guaranteed time and the remainder is open to the worldwide general astronomical community through a standard competitive proposal procedure.
A. Osterwalder, Y. Pigneur
H. Radder
Practicing and studying automated experimentation may benefit from philosophical reflection on experimental science in general. This paper reviews the relevant literature and discusses central issues in the philosophy of scientific experimentation. The first two sections present brief accounts of the rise of experimental science and of its philosophical study. The next sections discuss three central issues of scientific experimentation: the scientific and philosophical significance of intervention and production, the relationship between experimental science and technology, and the interactions between experimental and theoretical work. The concluding section identifies three issues for further research: the role of computing and, more specifically, automating, in experimental research, the nature of experimentation in the social and human sciences, and the significance of normative, including ethical, problems in experimental science.
Edward A. Lee
Cyber-Physical Systems (CPS) are integrations of computation and physical processes. Embedded computers and networks monitor and control the physical processes, usually with feedback loops where physical processes affect computations and vice versa. The economic and societal potential of such systems is vastly greater than what has been realized, and major investments are being made worldwide to develop the technology. There are considerable challenges, particularly because the physical components of such systems introduce safety and reliability requirements qualitatively different from those in general- purpose computing. Moreover, physical components are qualitatively different from object-oriented software components. Standard abstractions based on method calls and threads do not work. This paper examines the challenges in designing such systems, and in particular raises the question of whether today's computing and networking technologies provide an adequate foundation for CPS. It concludes that it will not be sufficient to improve design processes, raise the level of abstraction, or verify (formally or otherwise) designs that are built on today's abstractions. To realize the full potential of CPS, we will have to rebuild computing and networking abstractions. These abstractions will have to embrace physical dynamics and computation in a unified way.
E. Dahlman, S. Parkvall, Johan Sköld et al.
P. Krugman
W. Kast
P. Krugman
K. Judd
Chunho Lee, M. Potkonjak, W. Mangione-Smith
D. Lenat
P. Chen, A. D. Lambert, Kevin R. Guidry
V. Torres‐Company, A. Weiner
The outstanding phase‐noise performance of optical frequency combs has led to a revolution in optical synthesis and metrology, covering a myriad of applications, from molecular spectroscopy to laser ranging and optical communications. However, the ideal characteristics of an optical frequency comb are application dependent. In this review, the different techniques for the generation and processing of high‐repetition‐rate (>10 GHz) optical frequency combs with technologies compatible with optical communication equipment are covered. Particular emphasis is put on the benefits and prospects of this technology in the general field of radio‐frequency photonics, including applications in high‐performance microwave photonic filtering, ultra‐broadband coherent communications, and radio‐frequency arbitrary waveform generation.
Jiyoung Seo, Dong In Lee, Pilhyeon Lee et al.
Recognizing tool-based hand activities from a first-person view is a critical yet challenging task in computer vision, due to the complexity of hand-object interactions and often subtle, ambiguous motion patterns. In real-world manufacturing scenarios, these challenges are exacerbated by bidirectional action pairs whose visual cues are almost identical, with differences revealed only through subtle motion dynamics. However, existing datasets rarely capture these direction-sensitive interactions at scale, particularly in realistic tool-use contexts, limiting the ability of current models to learn fine-grained motion dynamics essential for accurate recognition. We introduce Ego-Bi (Egocentric-Bidirectional dataset), a large-scale, real-world egocentric RGB video dataset comprising 1,223 video sequences and 622,737 frames that cover diverse tool-use activities in unconstrained environments. Ego-Bi provides an extended 38-category hand type taxonomy, detailed object–tool labels, and challenging bidirectional action pairs, offering rich semantic and temporal cues for modeling complex hand–object interactions. In addition, to address the ambiguity in motion dynamics, we propose a BMP (Bidirectional Motion Prior module) that derives rotation and directional cues from predicted 3D hand poses to improve class separability of visually similar actions. Experimental results on Ego-Bi demonstrate that our approach improves bidirectional action recognition accuracy by + 8.96% over the baseline, while also yielding consistent gains across general action classes without requiring costly 3D pose annotations. Furthermore, the proposed motion priors generalize effectively to other egocentric benchmarks, underscoring their robustness in handling visually similar, direction-sensitive actions.
Svetlana S. Konnova, Pavel A. Lepilin, Anastasia A. Zanishevskaya et al.
Biosensor technologies in medicine, as in many other areas, are replacing labor-intensive methods of monitoring human health. This paper presents the results of experimental studies on label-free sensors based on a hollow core microstructured optical waveguide (HC-MOW) for human blood serum analysis. The MOWs with a hollow core of 247.5 µm in diameter were manufactured and used in our work. These parameters allow the hollow core to be filled with high-viscosity solutions due to the capillary properties of the fiber. Calculations of the spectral properties of the HC-MOW fiber were carried out and experimentally confirmed. Twenty-one blood serum samples from volunteers were analyzed using standard photometry (commercial kits) and an experimental biosensor. The obtained transmission spectra were processed by the principal component analysis method and conclusions were drawn about the possibility of using this biosensor in point-of-care medicine. A significant difference was shown between the blood serum of healthy patients and patients with confirmed diagnoses and a long history of cardiovascular system abnormalities. Algorithms for spectra processing using the Origin program are presented.
Anna Wajs-Bonikowska, Ewa Maciejczyk, Łukasz Szoka et al.
This study investigates the essential oil (EO) isolated from the seeds and cones of Canadian hemlock (<i>Tsuga canadensis</i>), highlighting notable differences in their chemical composition and biological activities. The seed EO was uniquely dominated by oxygenated derivatives of monoterpene hydrocarbons, particularly bornyl acetate (40%), whereas the cone EO exhibited higher levels of monoterpene hydrocarbons such as α-pinene (23%), β-pinene (20%), and myrcene (23%). A significant finding was the strong cytotoxic activity of cone EO against melanoma cell lines, with IC<sub>50</sub> values as low as 0.104 ± 0.015 μL/mL, compared to the minimal effects of seed EO. Additionally, cone EO demonstrated stronger antimicrobial activity, with lower minimum inhibitory concentrations (MICs) against Gram-positive and Gram-negative bacteria, further highlighting its therapeutic potential. Lipophilic extracts from seeds were characterized by unsaturated fatty acids (linoleic, oleic, and sciadonic acids—specific to conifers) and bioactive molecules with high antioxidant and nutritional potential, such as β-tocopherol, β-sitosterol, and campestrol. These findings underscore the unique chemical composition of <i>T. canadensis</i> seed EO and its lipophilic extract, along with the potent cytotoxic and antimicrobial properties of cone EO, offering insights into their potential applications in natural products for pharmaceutical and therapeutic uses.
Hemalatha Kanakarajan, Wouter De Baene, Patrick Hanssens et al.
Abstract Background and purpose Accurate segmentation of brain metastases on Magnetic Resonance Imaging (MRI) is tedious and time-consuming for radiologists that could be optimized with deep learning (DL). Previous studies assessed several DL algorithms focusing only on training and testing the models on the planning MRI only. The purpose of this study is to evaluate well-known DL approaches (nnU-Net and MedNeXt) for their performance on both planning and follow-up MRI. Materials and methods Pre-treatment brain MRIs were retrospectively collected for 255 patients at Elisabeth-TweeSteden Hospital (ETZ): 201 for training and 54 for testing, including follow-up MRIs for the test set. To increase heterogeneity, we added the publicly available MRI scans from the Mathematical oncology laboratory of 75 patients to the training data. The performance was compared between the two models, with and without the addition of the public data. To statistically compare the Dice Similarity Coefficient (DSC) of the two models trained on different datasets over multiple time points, we used Linear Mixed Models. Results All models obtained a good DSC (DSC > = 0.93) for planning MRI. MedNeXt trained with combined data provided the best DSC for follow-ups at 6, 15, and 21 months (DSC of 0.74, 0.74, and 0.70 respectively) and jointly the best DSC for follow-ups at three months with MedNeXt trained with ETZ data only (DSC of 0.78) and 12 months with nnU-Net trained with combined data (DSC of 0.71). On the other hand, nnU-Net trained with combined data provided the best sensitivity and FNR for most follow-ups. The statistical analysis showed that MedNeXt provides higher DSC for both datasets and the addition of public data to the training dataset results in a statistically significant increase in performance in both models. Conclusion The models achieved a good performance score for planning MRI. Though the models performed less effectively for follow-ups, the addition of public data enhanced their performance, providing a viable solution to improve their efficacy for the follow-ups. These algorithms hold promise as a valuable tool for clinicians for automated segmentation of planning and follow-up MRI scans during stereotactic radiosurgery treatment planning and response evaluations, respectively. Clinical trial number Not applicable.
Suvijak Untaaveesup, MD, Thipsukon Amnartpanich, MD, Noraworn Jirattikanwong, MD et al.
Background: Chronic systemic inflammation in individuals with moderate-to-severe atopic dermatitis (AD) potentially predisposes them to metabolic and cardiovascular diseases. Nevertheless, evidence with regard to such association is limited. Objective: To assess the association between metabolic and cardiovascular outcomes and moderate-to-severe AD. Methods: A systematic search was performed through PubMed, Scopus, EMBASE, and Cochrane for population-based studies that addressed the effects of moderate-to-severe AD on metabolic and cardiovascular outcomes compared with the general population from inception to August 31, 2023. Meta-analysis was performed using the random effects model. The pooled odds ratio (OR) and certainty of evidence for each outcome were reported. Results: We included 11 studies, 4 retrospective cohorts, 1 prospective cohort, 4 cross-sectional, and 2 case-control studies involving 405,170 moderate-to-severe AD patients compared to 4,591,478 unaffected controls. Moderate-to-severe AD was associated with a higher risk of myocardial infarction with an OR (95% CI) of 1.33 (1.07, 1.65), angina 1.33 (1.06, 1.66), heart failure 1.56 (1.28, 1.90), stroke 1.45 (1.21, 1.74), hypertension 1.38 (1.18, 1.63), dyslipidemia 1.27 (1.15, 1.41), and metabolic syndrome 1.24 (1.05, 1.42) with very low certainty of evidence. No significantly increased risk of cardiovascular death with an odds ratio (95% CI) of 1.81 (0.96, 3.44) and diabetes of 1.24 (0.91, 1.68) was observed. High heterogeneity was observed in most studies for all of the outcomes. Conclusion: Our meta-analysis demonstrated a modest but significant association between moderate-to-severe AD and increased susceptibility to metabolic and cardiovascular diseases. Initial assessment of cardiovascular and metabolic risk for patients with moderate-to-severe AD should be considered to enable early management strategies.
Xianying Cheng, Ping Wang, Li Cheng et al.
BackgroundCervical cancer incidence and mortality rates in the United States have substantially declined over recent decades, primarily driven by reductions in squamous cell carcinoma cases. However, the trend in recent years remains unclear. This study aimed to explore the trends in cervical cancer incidence and mortality, stratified by demographic and tumor characteristics from 1975 to 2018.MethodsThe age-adjusted incidence, incidence-based mortality, and relative survival of cervical cancer were calculated using the Surveillance, Epidemiology, and End Results (SEER)-9 database. Trend analyses with annual percent change (APC) and average annual percent change (AAPC) calculations were performed using Joinpoint Regression Software (Version 4.9.1.0, National Cancer Institute).ResultsDuring 1975–2018, 49,658 cervical cancer cases were diagnosed, with 17,099 recorded deaths occurring between 1995 and 2018. Squamous cell carcinoma was the most common histological type, with 34,169 cases and 11,859 deaths. Over the study period, the cervical cancer incidence rate decreased by an average of 1.9% (95% CI: −2.3% to −1.6%) per year, with the APCs decreased in recent years (−0.5% [95% CI: −1.1 to 0.1%] in 2006–2018). Squamous cell carcinoma incidence trends closely paralleled overall cervical cancer patterns, but the incidence of squamous cell carcinoma in the distant stage increased significantly (1.1% [95% CI: 0.4 to 1.8%] in 1990–2018). From 1995 to 2018, the overall cervical cancer mortality rate decreased by 1.0% (95% CI: −1.2% to −0.8%) per year. But for distant-stage squamous cell carcinoma, the mortality rate increased by 1.2% (95% CI: 0.3 to 2.1%) per year.ConclusionFor cervical cancer cases diagnosed in the United States from 1975 to 2018, the overall incidence and mortality rates decreased significantly. However, there was an increase in the incidence and mortality of advanced-stage squamous cell carcinoma. These epidemiological patterns offer critical insights for refining cervical cancer screening protocols and developing targeted interventions for advanced-stage cases.
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