Search Results (1,810)

The Weather Research and Forecasting Model (WRF-ARW) version 4.5 was used to simulate the synoptic to mesoscale evolving atmosphere of Tropical Cyclone (TC) Hilary’s (2023) remnant passage over the southwestern United States. The atmospheric dynamic processes conducive to the precursor rain events were extensively studied to determine the effects of mid-level jetogenesis. Concurrently, the dynamics of mesoscale processes related to the interaction of TC Hilary over the complex topography of the western United States were studied with several sensitivity simulations on a nested 2 km × 2 km grid. The differential surface heating between the cloudy California coast and clear/elevated Great Basin plateau had a profound impact on the lower-mid-tropospheric mass field resulting in mid-level jetogenesis. Diagnostic analyses of the ageostrophic flow support the importance of both isallobaric and inertial advective forcing of the mid-level jetogenesis in response to differential surface sensible heating. This ageostrophic mesoscale jet ultimately transported tropical moisture in multiple plumes more than 1000 km poleward beyond the location of the extratropical transition of the storm, resulting in anomalous flooding precipitation within a massive arid western plateau. Full article

This perspective paper aims to set the stage for current development in the field of energy consumption and environmental impacts in two major digital industries: cryptocurrency mining and artificial intelligence (AI). To better understand current developments, this paper uses a comparative analytical framework of life-cycle assessment principles and high-resolution grid modeling to explore the energy impacts from academic and industry data. On the one hand, while both sectors convert energy into digital value, they operate according to completely different logics, in the sense that cryptocurrencies rely on specialized hardware (application-specific integrated circuits) and seek cheap energy, where they can function as “virtual batteries” for the network, quickly shutting down at peak times, with increasing hardware efficiency. On the other hand, AI is a much more rigid emerging energy consumer, in the sense that it needs high-quality, uninterrupted energy and advanced infrastructure for high-performance Graphics Processing Units (GPUs). The training and inference stages generate massive consumption, difficult to quantify, and AI data centers put great pressure on the electricity grid. In this sense, the transition from mining to AI is limited due to differences in infrastructure, with the only reusable advantage being access to electrical capacity. Regarding competition between the two industries, this dynamic can fragment the energy grid, as AI tends to monopolize quality energy, and how states will manage this imbalance will influence the energy and digital security of the next decade. Full article

There exists an east–west trending albitite (breccia) zone, approximately 400 km in length, closely related to gold mineralization, in Devonian strata in the South Qinling tectonic belt. The genesis and formation age of these albitite (breccia) are of great significance for understanding gold enrichment mechanisms and guiding future exploration. Past studies have mainly focused on the Fengxian–Taibai area in the western segment of the albitite (breccia) zone, whereas the eastern segment remains significantly understudied. In this study, a systematic field investigation, as well as petrology, geochemistry, and accessory-mineral geochronology studies were conducted on albitites and albitite breccias in the Shangnan area, the eastern segment of the albitite (breccia) zone. The results show that the albitites are interlayered with or occur as lenses within Devonian clastic rocks. The albitite breccias are mostly enclosed in albitite and Devonian strata, and the clasts within are subangular, uniform in type, and exhibit minimal displacement. Both albitites and albitite breccias exhibit similar trace-element characteristics and detrital zircon age spectra to those of Devonian clastic rocks. Abundant hydrothermal monazites with U–Pb ages ranging from 260 to 252 Ma are present in both albitites and albitite breccias but absent in Devonian clastic rocks. Collectively, these results indicate that the albitites in the Shangnan area are of hydrothermal metasomatic origin, while the albitite breccias record hydraulic fracturing and cementation, and both are products of the same fluid activity event in the Late Permian. We propose that albitite (breccia) zones in the South Qinling tectonic belt were formed under distinct tectonic settings during different evolution stages of the Late Paleozoic Mianlüe Ocean. Specifically, the albitites (breccias) in the Shangnan area are products of thorough metasomatism, local fracturing, and cementation of Devonian clastic rocks by mixed fluids, which ascended along the Fengzhen–Shanyang Fault coeval with the emplacement of magmatic rocks related to subduction of the Mianlüe Ocean. In contrast, the albitite breccias in the Fengxian–Taibai area are the result of fluid activity during the transition from regional compression to extension after the closure of the Mianlüe Ocean. Full article

Internal Boxing (neijiaquan 內家拳) is an advanced form of the Daoist gymnastic exercise of daoyin (導引). However, how it achieves a paradigmatic shift from qi/blood regulation to deep-level transmutation of sexual energy still requires further exploration. Therefore, it is of great significance to look into how Internal Boxing inheres and integrates various techniques of “desire transmutation” (zhuanyu 轉欲) from internal alchemy (neidan 內丹), thereby transcending traditional daoyin, bringing about a significant systematic reconfiguration in the model of body cultivation practices in Daoist medicine. The traditional daoyin (i.e., “guiding and stretching”) practice emphasizes the regulation of qi/blood, but it remains limited in accounting for and producing the self-conscious transmutation of sexual energy. In contrast, Internal alchemy provides a different system of theory and techniques, which is centered on the concept of “transmutation of desires”, converting human desires into high-level life energy through a process of interaction between one’s internal spirit (xinshen 心神) and internal breathing (neixi 內息). This study thus examines the ways in which Internal Boxing integrates and reconfigures these techniques within its bodily training regimen. In the core of all these styles is the goal to refine the primordial essence (yuanjing 元精) by transitioning the method to induce the flow of vital energy from breathing to somatic movements. As a result, this study shows that the innovations of Internal Boxing reconfigure the qi/blood regulation model in the traditional daoyin practice, causing a systematic reconfiguration in the transmutation of sexual energy and, further, bridging the gap between daoyin and internal alchemy in both theory and practice. Furthermore, such innovations also develop a holistic view of the human body as marked by an emphasis on the “unity of pre-heaven (xiantian 先天) and post-heaven (houtian 後天) states”, which expands in both depth and breadth the theories of body cultivation practices in Daoist medicine. Full article

The development of multifunctional polymer composites capable of both heat conduction and latent heat storage is of great interest for advanced thermal management applications. In this work, thermoplastic polyurethane (TPU) nanocomposites containing microencapsulated paraffin-based phase change materials (PCMs) and multi-walled carbon nanotubes (MWCNTs) were systematically investigated. The microstructure, thermal stability, specific heat capacity, thermal diffusivity and conductivity of these composites were analyzed as a function of the PCM and MWCNTs content. SEM observations revealed the homogeneous dispersion of PCM microcapsules and the presence of localized MWCNT aggregates in PCM-rich domains. Thermal diffusivity measurements indicated a monotonic decrease with increasing temperature for all compositions, from 0.097 mm²·s⁻¹ at 5 °C to 0.091 mm²·s⁻¹ at 25 °C for neat TPU, and from 0.186 mm²·s⁻¹ to 0.173 mm²·s⁻¹ for TPU with 5 vol.% MWCNTs. Distinct non-linear behavior was observed around 25 °C, i.e., in correspondence to the paraffin melting, where the apparent diffusivity temporarily decreased due to latent heat absorption. The trend of the thermal conductivity (λ) was determined by the competing effects of PCM and MWCNTs: PCM addition reduced λ at 25 °C from 0.162 W·m⁻¹·K⁻¹ (neat TPU) to 0.128 W·m⁻¹·K⁻¹ at 30 vol.% PCM, whereas the incorporation of 5 vol.% of MWCNTs increased λ up to 0.309 W·m⁻¹·K⁻¹. In PCM-containing nanocomposites, MWCNT networks efficiently bridged the polymer–microcapsule interfaces, creating continuous conductive pathways that mitigated the insulating effect of the encapsulated paraffin and ensured stable heat transfer even across the solid–liquid transition. A one-dimensional transient heat-transfer model confirmed that increasing the matrix thermal conductivity accelerates the melting of the PCM, improving the dynamic thermal buffering capacity of these materials. Therefore, these results underlined the potential of TPU/MWCNT/PCM composites as versatile materials for applications requiring both rapid heat dissipation and effective thermal management. Full article

Despite significant breakthroughs in the study of microbial physiology, genetics, ecology, and other disciplines related to these fields of science, there are still quite a few “white spots” in this field. The so-called “resting state” of microbial cells leaves great opportunities for researchers. In this review, we have attempted to outline this problem and define its general nature. We have discussed the physiological processes that lead to the transition of microbial cells into various non-culturable states, as well as related terminological issues. We have also outlined the range of medical concerns and the potential for bio-technology. We have attempted to present the material in a way that reflects the historical development of the problem, and therefore, we have not neglected the bibliographic references from a relatively early period. Full article

The refined microstructure and enhanced mechanical properties of wire-arc directed energy deposition (WA-DED) Al-Cu alloys have attracted a great deal of attention in various industries. Despite numerous strengthening strategies developed to enhance the performance of Al-Cu alloys, the effect of scandium (Sc) in their as-deposited state has received limited attention. In this work, Al-Cu-Sc alloy samples with different Sc contents were designed and prepared by WA-DED technology with interlayer powder coating. The microstructural characteristics and mechanical properties of Al-Cu alloys with varying Sc contents were systematically compared by applying an alcohol-based solution with different Sc concentrations. The experimental results demonstrate that the addition of Sc promotes the columnar-to-equiaxed transition (CET). Moreover, compared to the Al-Cu-Sc alloy with lower Sc content (0.15%, average grain size: 128.35 μm), the alloy with higher Sc content (0.32%) exhibited a finer average grain size of 95.81 μm. The increased Sc content was also beneficial in suppressing the formation of solidification shrinkage pores. As the Sc content increases, the interconnected θ′-Al₂Cu phase breaks up, leading to its more uniform dispersion in the aluminum matrix. In terms of mechanical properties, the sample with higher Sc content demonstrated superior tensile properties, exhibiting an ultimate tensile strength (UTS) and elongation (EL) of 265.89 MPa and 12.29%, respectively, compared to 240.67 MPa and 9.05% for the Sc-L sample. In contrast, the yield strength (YS) and microhardness showed no significant variation with the change in Sc content. Full article

The northern Brazilian Amazon has ecological transition ecosystems with high diversity and endemism of tree species and few botanical collections. We evaluated the phytosociology between Dense Ombrophilous Forest (Ds) and Forested Campinarana (Ld) within Anauá National Forest in Roraima, Brazil. A total of 14,730 trees with a DBH ≥ 10 cm were inventoried across 30 hectares (ha), distributed among 55 botanical families, 183 genera, 386 species, and 123 undetermined trees. Ten hyperdominant tree families accounted for 69% of the sampled trees and 65% of the stored forest carbon (102.9 ± 5.0 Mg ha⁻¹), like Arecaceae (2555 trees), Fabaceae (1738 trees), and Sapotaceae (1311 trees). Ten hyperdominant species accounted for 32% of the sampled individuals and 32% of the stored forest carbon (46.3 ± 3.8 Mg ha⁻¹), like Euterpe precatoria (1151 trees), Pouteria macrophylla (561 trees) and Inga alba (574 trees). Anauá National Forest has great potential for sustainable multiple-use forest management through forest concessions; however, tree mortality due to natural causes and anthropogenic actions (deforestation, illegal selective logging, and forest fires) was considered high (7%) for tropical forests in the Amazon. Full article

Osteoarthritis (OA) is a degenerative joint disease characterized by cartilage degradation, inflammation, and pain, for which conventional systemic therapies often lack sustained efficacy. Therefore, localized delivery platforms that provide both sustained release and therapeutic activity are urgently needed. We developed a thermosensitive injectable hydrogel—hydroxybutyl chitosan (HBC)—that transitions from a sol to a gel at physiological temperature (37 °C). Curcumin, a natural anti-inflammatory compound with poor bioavailability, was loaded to create a composite hydrogel system (Cur@HBC). HBC exhibited excellent injectability, stability, and biocompatibility. Cur@HBC enabled sustained release of curcumin and significantly attenuated OA progression in vivo, as evidenced by reduced cartilage degradation, decreased expression of MMP13 and pro-inflammatory cytokines (IL-1β, IL-6, TNF-α), improved Collagen II retention, and recovery of cartilage function. Mechanistically, curcumin inhibited chondrocyte apoptosis and promoted macrophage polarization toward the M2 phenotype. This study presents a dual-functional hydrogel platform that combines thermosensitive mechanical support with sustained anti-inflammatory drug delivery. The injectable Cur@HBC hydrogel shows great promise as a localized OA therapy, with the potential to improve joint function. Full article

Irreversible erosion damage of the hearth lining determines the campaign life of a blast furnace (BF). Among the factors involved, structural thermal stress resulting from both internal and external temperature differences and external constraints is a key mechanism in the damage to the hearth lining. Based on a thermal–fluid–structural coupling model that accounts for molten iron flow and solidification, this study, building on thermal stress analysis of the hearth lining, proposes a method to determine the critical strength-based erosion boundary of the lining, using the compressive strength of carbon bricks as the criterion. It also investigates the influence of factors such as dead iron layer depth, tapping productivity, and molten iron temperature on the thermal stress-driven erosion boundary. The findings reveal that the depth of the dead iron layer determines the morphology of the hearth lining’s erosion. With increasing depth, the erosion pattern transitions from an elephant foot profile to a wide-face profile, while the radial erosion depth first increases and then decreases. Both increased tapping productivity and elevated molten iron temperature do not change the erosion shape but aggravate the erosion degree and induce axial displacement of the erosion zone. The research findings are of great significance for deepening the understanding of thermal stress damage in the hearth lining and provide an effective reference for long-term hearth design. Subsequent validation with a large amount of industrial data will further enhance the practical applicability of the proposed method. Full article

By analyzing new findings from the literature on immunometabolism during the transition period, as well as classical concepts, we aim to propose a new approach to the inflammation paradigm in cows transitioning from gestation to lactation. The purpose of this review, based on data from scientific articles and reviews, is to characterize the immunometabolism of the transition period, highlighting the main characteristics of the inflammatory response in dairy cows and listing the mechanisms that govern inflammatory tone and coordinate the resolution of inflammation, with a view of new paradigms and analysis of non-classical pathways. We also seek to analyze inflammation and the role of mitochondria and the endoplasmic reticulum in the genesis of diseases, proposing approaches for modulating inflammatory tone. This review analyzes the classical theoretical approach using mechanistic views anchored in knowledge produced in other species and based on new evidence from the bovine field, determining new paradigms. This study highlights the constant inflammatory condition during the transition period and its effect on metabolism and demonstrates the role of dysregulation of inflammation resolution as a central factor in the genesis of diseases. Purinergic and cholinergic anti-inflammatory pathways have been little explored in cattle, but it is believed that the role of these pathways in maintaining homeostasis represents a great opportunity for understanding and modulating the phenomenon of inflammation in dairy cows. Dysregulation of the stress axis shows elucidative potential regarding the dysregulation of inflammatory resolution, with mitochondrial health and endoplasmic reticulum stress being dividing factors between homeorhetic and pathological states. Modulating inflammation and establishing inflammatory resolution presents challenges with classic anti-inflammatory drugs due to the paradoxical role of prostaglandin E2 in inflammation and resolution. Phytoactives offer new possibilities for modulating inflammation without disrupting inflammatory resolution and ensuring antioxidant effects, associated with strategies for formulating less inflammatory diets. Full article

The Wunuer deposit is an important hydrothermal Zn-Pb-Ag-Mo polymetallic deposit in the central Great Xing’an Range, NE China. The zinc–lead polymetal mineralization is closely hosted by the volcanic rocks of the Manketouebo formation (rhyolite and lithic crystal tuff) and related to the Mesozoic granite porphyry. Field evidence and petrographic observations have identified three mineralization stages within this deposit from deep to shallow: (1) late magmatic stage with vein-type Mo mineralization characteristics and mainly related to the deep granite porphyry; (2) magmatic–hydrothermal transition stage characterized by breccia-type Zn mineralization, which occurred within a steep cryptoexplosive breccia; and (3) hydrothermal stage featured by vein-type Zn-Pb-Ag mineralization hosted by the ore-bearing fractured zone. In this contribution, we present the mineralogy, zircon U-Pb age, sphalerite Rb-Sr dating, whole-rock geochemistry, and Hf-S-Pb isotopes of the Wunuer deposit. LA-ICP-MS zircon U-Pb dating of the ore-related granite porphyry, rhyolite, and lithic crystal tuff suggests that the Mo mineralization from the late magmatic stage occurred between 144.8 Ma and 145.8 Ma. The Rb-Sr isochron dating of sphalerite indicates that the hydrothermal stage Zn mineralization age is 121 ± 2.3 Ma, which is related to the volcanism of Baiyin’gaolao Formation in the Wunuer area. The concentrated and positive δ³⁴S_V-CDT values (0.17‰~5.40‰) of sulfides, as well as uniform Pb isotope compositions of granite porphyry intrusion and galena, jointly imply a magmatic source of metallogenic materials for Pb-Zn mineralization. Whole-rock geochemistry and Hf-Pb isotopes reveal that the granite porphyry and rhyolite both originated from a mantle-derived juvenile component and assimilated by minor ancient crustal material in an extensional setting. Our study demonstrates the prospect of further exploration for two mineralization events in the hydrothermal polymetallic deposits of the central Great Xing’an Range. Full article

Background: There is a great deal of knowledge regarding the development of polyomavirus-associated nephropathy and polyomavirus-associated hemorrhagic cystitis in transplant recipients with active BKPyV infection. However, recent studies have revealed a potential association between BKPyV reactivation and certain malignancies, including transitional cell carcinoma, malignant melanoma, colorectal cancer, and prostate cancer. This study aimed to identify a potential link between BKPyV infection and oncogenic transformation in kidney transplant recipients. Methods: Presentation of a case series of kidney transplant recipients diagnosed with polyomavirus-associated nephropathy who developed neoplasms after transplantation. Results: Positive immunohistochemical reactions confirmed the presence of polyomavirus large T antigen in tissue samples from all three patients’ cancers. Furthermore, a case of chromophobe renal cell carcinoma presenting BKPyV proteins in cancer cells was observed for the first time in the literature. Conclusions: BKPyV reactivation was found to be associated with the development of both urothelial cancer, which originates directly from the BKPyV-infected site, and colorectal cancer. Full article

Forward-swept wings are more suitable for natural laminar flow than backward-swept wings. However, in order to reduce the difficulty of optimization, most aero-structural optimization studies of forward-swept wings do not consider the automatic laminar–turbulent transition, discrete variables, or large-scale constraints, which may result in undesirable optimization results. In this article, an efficient aero-structural optimization method for the composite forward-swept natural laminar flow (FSNLF) wing is proposed, which can solve MDO problems with those issues. Reynolds-averaged Navier–Stokes (RANS) equations coupled with the dual e^N transition method are used to simulate subsonic viscous flows. A surrogate-based optimization (SBO) algorithm combining a discrete variable handling method is developed to solve the multidisciplinary design optimization (MDO) problem involving many discrete ply thickness variables of predefined angles (0°/±45°/90°). The Kreisselmeier–Steinhauser (KS) method is employed to handle large-scale geometric constraints, ply fraction constraints and material failure constraints. To verify the effectiveness of the proposed method, we perform the aero-structural optimization of an A320-class composite FSNLF wing. Results show that the proposed method offers great potential in the aero-structural optimization of the composite FSNLF wing. It can handle 32 discrete variables and 11,089 constraints, the drag coefficient and mass of the wing are reduced significantly, and the area of the laminar flow region on the wing upper surface is increased by 24.3% compared with the baseline. Full article

The functional integration of chiral liquid crystals and π-conjugated compounds has great potential for creating novel exotic materials. A series of chiral donor–acceptor (D–A)-type fluorenone derivatives was synthesized to investigate the influence of molecular structure upon their liquid-crystalline phase-transition behavior, ferroelectricity, photophysical properties, and photoconductive properties. Polarizing optical microscopy (POM), differential scanning calorimetry (DSC), and X-ray diffraction (XRD) analyses revealed that several D–A-type fluorenone derivatives exhibited liquid crystal (LC) phases. These chiral LC fluorenone derivatives exhibited polarization hysteresis in the chiral smectic C (SmC*) phase. Among the four fluorenone-based ferroelectric liquid crystals (FLCs), (R,R)-2a exhibited the largest spontaneous polarization (over 3.0 × 10² nC cm⁻²). The formation of intramolecular charge-transfer (ICT) states in each compound was evidenced by the UV–vis absorption spectroscopy. Ambipolar carrier transport in the SmC* phases of the fluorenone-based FLCs was elucidated by the time-of-flight (TOF) method. The mobilities of holes and electrons in the SmC* phases were on the order of 10⁻⁵ cm² V⁻¹ s⁻¹, which is on par with the carrier mobilities of low-ordered smectic phases in conventional LC semiconductors. Full article