Jet-dominated quiescent states in black hole X-ray binaries: the case of V404 Cyg

The dynamical and radiative properties of the quiescent state (X-ray luminosity $<10^{34}\ {\rm erg s^{-1} cm^{-2}}$) of black hole X-ray transients (BHXTs) remains unclear, mainly because of low-luminosity and poor data quantity. We demonstrate that, the simultaneous multi-wavelength (including radio, optical, ultraviolet and X-ray bands) spectrum of V404 Cyg in its bright quiescent state can be well described by the radiation from the companion star and more importantly, the compact jet. Neither the outer thin disc nor the inner hot accretion flow is important in the total spectrum. Together with several additional recent findings, i.e. the power-law X-ray spectrum and the constant X-ray spectral shape (or constant photon index) in contrast to the dramatic change in the X-ray luminosity, we argue the quiescent state spectrum of BHXTs is actually jet-dominated. Observational features consistent with this jet model are also discussed as supporting evidences.Comment: accepted for the publication in MNRAS Letters, 5 pages, 2 figure

Characteristics of the spatio-temporal evolution of the improved integrated ecological effect index (IEEI) in mountainous province based on remote sensing: a case study in Yunnan province of southwest China

Land use/cover change (LUCC) and the evaluation of its ecological effects are the important and key areas of research on global environmental change and sustainable development. In response to the problems and limitations of various methods of evaluating the ecological effects of LUCC, this article takes Yunnan Province, a mountainous province with a relatively fragile “innate” ecological environment, as the research area. Based on LUCC data from the interpretation of seven phases of remote sensing (RS) images taken in Yunnan, combined with the investigation of soil erosion data by using remote sensing technology, an improved integrated ecological effect index (IEEI) for the LUCC and a method for its evaluation are proposed; this index was applied to calculate the integrated ecological effect index for the LUCC and analyze its spatiotemporal evolution in 129 counties in Yunnan from 1990 to 2020. The spatiotemporal changes, characteristics, and laws of the integrated ecological effects of LUCC in the whole province and counties from 1990 to 2020 were revealed, with the goal of offering a fundamental framework for long-term strategic planning and management in mountainous provinces. Overall, in the past 30 years, the integrated ecological effect of Yunnan Province and various counties has significantly improved. However, the IEEI of the province is not yet very high, and its regional differences are significant. It is urgent to increase the efforts of ecological civilization construction (ECC) throughout the province, adopt practical and effective ecologically-friendly land use ways and ecological environment protection and construction measures according to local conditions, and steadily improve the integrated ecological effect of various regions

Knowledge-aware Alert Aggregation in Large-scale Cloud Systems: a Hybrid Approach

Due to the scale and complexity of cloud systems, a system failure would trigger an "alert storm", i.e., massive correlated alerts. Although these alerts can be traced back to a few root causes, the overwhelming number makes it infeasible for manual handling. Alert aggregation is thus critical to help engineers concentrate on the root cause and facilitate failure resolution. Existing methods typically utilize semantic similarity-based methods or statistical methods to aggregate alerts. However, semantic similarity-based methods overlook the causal rationale of alerts, while statistical methods can hardly handle infrequent alerts. To tackle these limitations, we introduce leveraging external knowledge, i.e., Standard Operation Procedure (SOP) of alerts as a supplement. We propose COLA, a novel hybrid approach based on correlation mining and LLM (Large Language Model) reasoning for online alert aggregation. The correlation mining module effectively captures the temporal and spatial relations between alerts, measuring their correlations in an efficient manner. Subsequently, only uncertain pairs with low confidence are forwarded to the LLM reasoning module for detailed analysis. This hybrid design harnesses both statistical evidence for frequent alerts and the reasoning capabilities of computationally intensive LLMs, ensuring the overall efficiency of COLA in handling large volumes of alerts in practical scenarios. We evaluate COLA on three datasets collected from the production environment of a large-scale cloud platform. The experimental results show COLA achieves F1-scores from 0.901 to 0.930, outperforming state-of-the-art methods and achieving comparable efficiency. We also share our experience in deploying COLA in our real-world cloud system, Cloud X.Comment: Accepted by Proceedings of the 46th International Conference on Software Engineering: Software Engineering in Practice (ICSE SEIP 2024

Causal relationship between human blood metabolites and risk of ischemic stroke: a Mendelian randomization study

Background: Ischemic stroke (IS) is a major cause of death and disability worldwide. Previous studies have reported associations between metabolic disorders and IS. However, evidence regarding the causal relationship between blood metabolites and IS lacking.Methods: A two-sample Mendelian randomization analysis (MR) was used to assess the causal relationship between 1,400 serum metabolites and IS. The inverse variance-weighted (IVW) method was employed to estimate the causal effect between exposure and outcome. Additionally, MR-Egger regression, weighted median, simple mode, and weighted mode approaches were employed as supplementary comprehensive evaluations of the causal effects between blood metabolites and IS. Tests for pleiotropy and heterogeneity were conducted.Results: After rigorous selection, 23 known and 5 unknown metabolites were identified to be associated with IS. Among the 23 known metabolites, 13 showed significant causal effects with IS based on 2 MR methods, including 5-acetylamino-6-formylamino-3-methyluracil, 1-ribosyl-imidazoleacetate, Behenoylcarnitine (C22), N-acetyltyrosine, and N-acetylputrescine to (N (1) + N (8))-acetate,these five metabolites were positively associated with increased IS risk. Xanthurenate, Glycosyl-N-tricosanoyl-sphingadienine, Orotate, Bilirubin (E,E), Bilirubin degradation product, C17H18N2O, Bilirubin (Z,Z) to androsterone glucuronide, Bilirubin (Z,Z) to etiocholanolone glucuronide, Biliverdin, and Uridine to pseudouridine ratio were associated with decreased IS risk.Conclusion: Among 1,400 blood metabolites, this study identified 23 known metabolites that are significantly associated with IS risk, with 13 being more prominent. The integration of genomics and metabolomics provides important insights for the screening and prevention of IS

New therapeutic directions in type II diabetes and its complications: mitochondrial dynamics

As important organelles of energetic and metabolism, changes in the dynamic state of mitochondria affect the homeostasis of cellular metabolism. Mitochondrial dynamics include mitochondrial fusion and mitochondrial fission. The former is coordinated by mitofusin-1 (Mfn1), mitofusin-2 (Mfn2), and optic atrophy 1 (Opa1), and the latter is mediated by dynamin related protein 1 (Drp1), mitochondrial fission 1 (Fis1) and mitochondrial fission factor (MFF). Mitochondrial fusion and fission are generally in dynamic balance and this balance is important to preserve the proper mitochondrial morphology, function and distribution. Diabetic conditions lead to disturbances in mitochondrial dynamics, which in return causes a series of abnormalities in metabolism, including decreased bioenergy production, excessive production of reactive oxygen species (ROS), defective mitophagy and apoptosis, which are ultimately closely linked to multiple chronic complications of diabetes. Multiple researches have shown that the incidence of diabetic complications is connected with increased mitochondrial fission, for example, there is an excessive mitochondrial fission and impaired mitochondrial fusion in diabetic cardiomyocytes, and that the development of cardiac dysfunction induced by diabetes can be attenuated by inhibiting mitochondrial fission. Therefore, targeting the restoration of mitochondrial dynamics would be a promising therapeutic target within type II diabetes (T2D) and its complications. The molecular approaches to mitochondrial dynamics, their impairment in the context of T2D and its complications, and pharmacological approaches targeting mitochondrial dynamics are discussed in this review and promise benefits for the therapy of T2D and its comorbidities

Case study of a rhizosphere microbiome assay on a bamboo rhizome with excessive shoots.

Peer reviewe

MODEL OF CROATIAN SEA PASSENGER PORTS MANAGEMENT RATIONALIZATION

Predmet istraživanja u ovome znanstvenom radu je razvitak pomorskoputničkih luka u Republici Hrvatskoj do 2012. godine. Za definiranje svojstava i determinanti pomorskoputničkih luka koristilo se modelom na bazi matrice rasta. Analiza i vrednovanje pojedinih elemenata modela i dobivene izravne stope rasta imale su za cilj znanstveno formulirati rezultate istraživanja, prema najvažnijim teorijskim zakonitostima razvitka pomorskoputničkih luka u Republici Hrvatskoj. Autori su se u znanstvenom istraživanju i prezentiranju rezultata istraživanja ovog rada služili kombinaciju znanstvenih metoda kao što su: metoda analize i sinteze, metoda konkretizacije, komparativna metoda i metoda modeliranja (matrica rasta). Glavna znanstvena hipoteza dokazana je izravnim stopama rasta odabranih elemenata modela a ona glasi: Znanstveno utemeljenim spoznajama o funkcioniranju i poslovanju sustava pomorskoputničkih luka moguće je predložiti model, mjere i aktivnosti za racionalno upravljanje tim lukama kako bi se osigurao rast i razvoj sustava pomorskoputničkih luka.This paper analyses the sustainable development of sea passenger ports in the Republic of Croatia until 2012. A model of growth was used in order to define the main characteristics and determinants of sea passenger ports. The purpose of the paper was to present a scientifically-based formulation of sustainable development analysis of sea passenger ports in Croatia, based on the evaluation and analysis of relevant elements and resulting direct rates. The authors in their scientific research and presentation used a various combination of scientific methods like: analysis and syntheses method, concretization method, comparative method and modeling method (growth matrix). The main scientific hypothesis is: By using scientifically based acknowledgments about functioning and management of sea passenger port system it is possible to suggest a model, measurements and activities for the rational management of sea passenger ports in Croatia in order to secure their growth and development. This scientific hypothesis was confirmed by the direct rates of growth of the model elements

Persistent sulfate formation from London Fog to Chinese haze

Sulfate aerosols exert profound impacts on human and ecosystem health, weather, and climate, but their formation mechanism remains uncertain. Atmospheric models consistently underpredict sulfate levels under diverse environmental conditions. From atmospheric measurements in two Chinese megacities and complementary laboratory experiments, we show that the aqueous oxidation of SO2 by NO2 is key to efficient sulfate formation but is only feasible under two atmospheric conditions: on fine aerosols with high relative humidity and NH3 neutralization or under cloud conditions. Under polluted environments, this SO2 oxidation process leads to large sulfate production rates and promotes formation of nitrate and organic matter on aqueous particles, exacerbating severe haze development. Effective haze mitigation is achievable by intervening in the sulfate formation process with enforced NH3 and NO2 control measures. In addition to explaining the polluted episodes currently occurring in China and during the 1952 London Fog, this sulfate production mechanism is widespread, and our results suggest a way to tackle this growing problem in China and much of the developing world