Proving Expected Sensitivity of Probabilistic Programs with Randomized Variable-Dependent Termination Time

The notion of program sensitivity (aka Lipschitz continuity) specifies that changes in the program input result in proportional changes to the program output. For probabilistic programs the notion is naturally extended to expected sensitivity. A previous approach develops a relational program logic framework for proving expected sensitivity of probabilistic while loops, where the number of iterations is fixed and bounded. In this work, we consider probabilistic while loops where the number of iterations is not fixed, but randomized and depends on the initial input values. We present a sound approach for proving expected sensitivity of such programs. Our sound approach is martingale-based and can be automated through existing martingale-synthesis algorithms. Furthermore, our approach is compositional for sequential composition of while loops under a mild side condition. We demonstrate the effectiveness of our approach on several classical examples from Gambler's Ruin, stochastic hybrid systems and stochastic gradient descent. We also present experimental results showing that our automated approach can handle various probabilistic programs in the literature

Proving expected sensitivity of probabilistic programs with randomized variable-dependent termination time

The notion of program sensitivity (aka Lipschitz continuity) specifies that changes in the program input result in proportional changes to the program output. For probabilistic programs the notion is naturally extended to expected sensitivity. A previous approach develops a relational program logic framework for proving expected sensitivity of probabilistic while loops, where the number of iterations is fixed and bounded. In this work, we consider probabilistic while loops where the number of iterations is not fixed, but randomized and depends on the initial input values. We present a sound approach for proving expected sensitivity of such programs. Our sound approach is martingale-based and can be automated through existing martingale-synthesis algorithms. Furthermore, our approach is compositional for sequential composition of while loops under a mild side condition. We demonstrate the effectiveness of our approach on several classical examples from Gambler's Ruin, stochastic hybrid systems and stochastic gradient descent. We also present experimental results showing that our automated approach can handle various probabilistic programs in the literature

Fuzzy evaluation of low carbon development levels for logistic enterprises in China

Purpose: Under the background of global warming, low carbon economy, which is based on low waste and low pollution, has become a globally focused topic. Energy conservation, emission reduction and low carbon development have become irresistible trends of social development. A new set of low carbon evaluation index system for logistics enterprises is proposed. It is helpful for the better monitor of low carbon production and provide the optimization of industrial policies in China. Design/methodology/approach: Based on the problem that logistic analyses are facing under the background of low carbon economy, this paper firstly establishes a set of new evaluation indexes system, including 5 first-level indices and 28 second-level indices, for the low carbon development levels of logistics enterprises in China. To simplify the new evaluation system, the weight judgment method is then used to select indices, the validity judgment method and reliability coefficient judgment method are respectively used to test the validity and reliability of the evaluation systems. The simplified evaluation system consists of 4 first-class indices and 20 second-class indexes. Finally, numerical examples illustrate the validity and operability of the evaluation system. Findings: From the analysis and evaluation results, it is not difficult to obtain the rank of logistics enterprise according to the selected indexes or the overall evaluation indices. Low scores of some key indexes in strategy indices and technical indices cause low carbon emission performance. Moreover, The reason for the good low carbon performance of one enterprises is that it is in the lead on the key indexes of high weighs such as Perfection degree of low carbon development strategy, Level of transportation route optimization, etc. The new evaluation index system also helps enterprises to realize the sustainable development by identifying the key factors that affect the low carbon development level. Originality/value: The existing literature that assesses low carbon logistics is mostly focused on the review of the location-based and industry-based aspects, and little attention has been paid to assessing the efficiency of low carbon logistics from the components that are within the logistics enterprises. Therefore, we develop a new low carbon evaluation index system for logistics enterprises in order to better monitor low carbon production and provide the optimization of industrial policies in China.Peer Reviewe

Loss-of-function mutations with circadian rhythm regulator Per1/Per2 lead to premature ovarian insufficiency

The mechanism underlying premature ovarian insufficiency remains incompletely understood. Here we report that mice with Per1m/m; Per2m/m double mutations display a decrease in female fertility starting approximately at 20 weeks old, with significantly less pups born from 32 weeks old onwards. Histological analysis revealed that a significant reduction of ovarian follicles was observed in the Per1/Per2 mutants compared with the littermate controls examined at 26 and 52 weeks old, while the difference was not statistically significant between the two groups at 3 and 8 weeks old. We further showed that vascular development including the ovarian follicle associated vascular growth appeared normal in the Per1/Per2 mutant mice, although clock genes were reported to regulate angiogenesis in zebrafish. The findings imply that loss-of-function mutations with Per1/Per2 result in a premature depletion of ovarian follicle reserve leading to the decline of reproductive capacity.Peer reviewe

Developing a class of dual atom materials for multifunctional catalytic reactions

Dual atom catalysts, bridging single atom and metal/alloy nanoparticle catalysts, offer more opportunities to enhance the kinetics and multifunctional performance of oxygen reduction/evolution and hydrogen evolution reactions. However, the rational design of efficient multifunctional dual atom catalysts remains a blind area and is challenging. In this study, we achieved controllable regulation from Co nanoparticles to CoN4 single atoms to Co2N5 dual atoms using an atomization and sintering strategy via an N-stripping and thermal-migrating process. More importantly, this strategy could be extended to the fabrication of 22 distinct dual atom catalysts. In particular, the Co2N5 dual atom with tailored spin states could achieve ideally balanced adsorption/desorption of intermediates, thus realizing superior multifunctional activity. In addition, it endows Zn-air batteries with long-term stability for 800 h, allows water splitting to continuously operate for 1000 h, and can enable solar-powered water splitting systems with uninterrupted large-scale hydrogen production throughout day and night. This universal and scalable strategy provides opportunities for the controlled design of efficient multifunctional dual atom catalysts in energy conversion technologies

Wstępne badanie jąkania i zwykłych niepłynności w mowie u dwujęzycznych polsko‑angielskich dorosłych osób z jąkaniem – studia przypadków

This study analyzes the frequency of stuttering and typical disfluencies in Polish‑English bilingual adults who stutter during cross‑linguistic dialogue, monologue, and oral reading contexts. Additionally, the relationship between English proficiency and stuttering and typical disfluency frequencies was examined. The study aims to contribute to the body of research regarding differential considerations between monolingual and bilinguals who stutter. Data collection took place via video conferencing. Participants first completed an English proficiency cloze test, where they entered missing words in a short English text. Following this, randomized dialogue, monologue, and oral reading speech samples in Polish and English were collected. The correlation between cloze test scores and frequency of stuttering and typical disfluency in the English samples was also examined. All participants experienced more stuttering in English (L2) than Polish (L1) during dialogue. Overall, participants had increased stuttering in L2 for at least one speaking task. Seventy one percent of participants had increased typical disfluencies in L2 for dialogue and monologue. Most participants evidenced an increase in stuttering and typical disfluencies in L2 compared to L1. The results suggest that language proficiency may share a relationship between frequency of stuttering and typical disfluencies, highlighting the importance of collecting cross‑linguistic speech data during assessment to reach clinical decisions related to fluency disorders in bilingual populations.W artykule przeanalizowano częstotliwość występowania symptomów jąkania i tzw. zwykłych niepłynności u dwujęzycznych (polsko‑angielskich) dorosłych osób z jąkaniem. Próbki zbierano podczas dialogu, monologu i czytania. Dokonano porównań pomiędzy obydwoma językami. Dodatkowo zbadano związek pomiędzy znajomością języka angielskiego a częstotliwością występowania symptomów jąkania i tzw. zwykłych niepłynności. Celem badania było pogłębienie wiedzy na temat różnic pomiędzy jedno‑ i dwujęzycznymi osobami, które się jąkają. Dane były pozyskiwane podczas sesji online. Uczestnicy najpierw wypełnili angielski test biegłości Cloze. Następnie zbierano randomizowane próbki mowy podczas dialogu, monologu i głośnego czytania w języku polskim i angielskim. Zbadano również korelację pomiędzy wynikami testu Cloze a częstotliwością jąkania i tzw. zwykłych niepłynności w próbkach angielskich. Wszyscy uczestnicy manifestowali więcej przejawów jąkania się w języku angielskim niż polskim podczas dialogu. Uczestnicy jąkali się bardziej w języku angielskim w co najmniej jednym zadaniu (dialog, monolog lub czytanie). Siedemdziesiąt jeden procent uczestników prezentowało podwyższony poziom tzw. zwykłych niepłynności w tym języku podczas dialogu i monologu. U większości uczestników objawy jąkania się i tzw. zwykłych niepłynności były bardziej nasilone w języku angielskim w porównaniu z polskim. Wyniki sugerują, że biegłość językowa może mieć związek z częstotliwością występowania objawów jąkania się i tzw. zwykłych niepłynności. W celu podejmowania decyzji klinicznych związanych z zaburzeniami płynności mowy w populacjach dwujęzycznych podczas diagnozy istotne jest dokonanie oceny w obu językach

Four volcanically driven climatic perturbations led to enhanced continental weathering during the Late Triassic Carnian Pluvial Episode

The arid climate of the Late Triassic was interrupted by a particularly humid episode known as the Carnian Pluvial Episode (CPE; ca. 234–232 million years ago). The CPE is often linked to eruptions in the Wrangellia Large Igneous Province (LIP), and is assumed to have led to global warming, enhanced weathering, water deoxygenation, and biotic changes. However, direct evidence for a temporal link between volcanic activity and chemical weathering has not yet been established due to the lack of comprehensive records across the CPE. In this study, geochemical and mineralogical analyses are applied to a lacustrine stratigraphic succession of the Jiyuan Basin (North China) that captures the CPE in high resolution. We identify four distinct pulses of enhanced continental chemical weathering characterized by elevated Chemical Index of Alteration values and kaolinite contents. These peaks in continental weathering coincide with Hg/TOC enrichments and negative organic carbon isotope excursions that mark four short (~400 kyr) but intense pulses of Wrangellia LIP volcanism. In combination with signs of increased humidity, our findings provide direct and independent evidence that Wrangellia LIP eruptions significantly altered CPE chemical weathering rates in response to global warming and wetting. The lake experienced eutrophication and water deoxygenation after each volcanic pulse but the swift recovery of carbon isotopes suggests that the system rapidly returned to conditions prior to the volcanic perturbation. Organic carbon burial facilitated by widespread dysoxic and anoxic waters, and CO2 consumption via enhanced weathering likely played crucial roles in the rapid climatic recovery after each volcanic pulse

Different wildfire types promoted two-step terrestrial plant community change across the Triassic-Jurassic transition

Frequent wildfires associated with emplacement of the Central Atlantic Magmatic Province (CAMP) are thought to have been important drivers of two significant changes in terrestrial plant communities and diversity during the Triassic-Jurassic Mass Extinction (TJME, ca. 201.51 Ma). ​However, it remains to be investigated whether these two changes are potentially related to different wildfire types. To better understand this relationship, we used a new method to reanalyze fossil pollen and spores across the Triassic-Jurassic transition in the Jiyuan Basin from the North China Plate. Results show that two peaks in wildfire frequency experienced different types of wildfires, with each linked to significant changes in plant communities and diversity losses. In the first wildfire peak, canopy fires dominated and are accompanied by significant losses of canopy forming plants, while in the second wildfire peak, ground cover fires dominated accompanied by significant losses of ground cover plants. ​Changes in atmospheric humidity conditions were an important control on the two different wildfire peaks. Relatively humid climatic conditions corresponded to the prevalence of canopy fires and hindered the spread and development of ground cover fires in wet surface conditions. Conversely, relatively arid climatic conditions corresponded with the prevalence of ground cover fires in dry surface environments. Our results provide a potential relationship between terrestrial plant communities and wildfire types, which is important to further understanding of terrestrial environmental and floral changes driven by Large Igneous Provinces

Different wildfire types promoted two-step terrestrial plant community change across the Triassic-Jurassic transition

Frequent wildfires associated with emplacement of the Central Atlantic Magmatic Province (CAMP) are thought to have been important drivers of two significant changes in terrestrial plant communities and diversity during the Triassic-Jurassic Mass Extinction (TJME, ca. 201.51 Ma). ​However, it remains to be investigated whether these two changes are potentially related to different wildfire types. To better understand this relationship, we used a new method to reanalyze fossil pollen and spores across the Triassic-Jurassic transition in the Jiyuan Basin from the North China Plate. Results show that two peaks in wildfire frequency experienced different types of wildfires, with each linked to significant changes in plant communities and diversity losses. In the first wildfire peak, canopy fires dominated and are accompanied by significant losses of canopy forming plants, while in the second wildfire peak, ground cover fires dominated accompanied by significant losses of ground cover plants. ​Changes in atmospheric humidity conditions were an important control on the two different wildfire peaks. Relatively humid climatic conditions corresponded to the prevalence of canopy fires and hindered the spread and development of ground cover fires in wet surface conditions. Conversely, relatively arid climatic conditions corresponded with the prevalence of ground cover fires in dry surface environments. Our results provide a potential relationship between terrestrial plant communities and wildfire types, which is important to further understanding of terrestrial environmental and floral changes driven by Large Igneous Provinces