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We present an experimental study of proton acceleration driven by femtosecond multi-PW lasers of three different prepulse parameters with the peak laser intensity of 1.2 × 1021 W/cm2 irradiating micrometre-thick metal foils. For 4-μm-thick copper foils, the highest-energy proton beam of 58.9 MeV is generated with the moderate-contrast laser, while the low-contrast or high-contrast lasers result in the lower proton cutoff energies. The one-dimensional hydrodynamic and two-dimensional particle-in-cell simulations indicate that the front preplasma of foils induced by the laser prepulse can enhance electron acceleration and in turn improve proton acceleration, while the rear preplasma will weaken the sheath field and be unfavourable for accelerating ions. For the case of the moderate contrast, the scale length of the front preplasma is long enough to generate high-temperature electrons compared to the high-contrast case, and the scale length of the rear preplasma is so short that the sheath field still remains strong compared with the low-contrast case, which is advantageous for generating high-energy protons. Meanwhile, a concrete map is theoretically given for accelerating higher-energy protons. This work extends the concept of the prepulse effect on target normal sheath acceleration (TNSA) to a wider range of laser parameters (multi-PW, 1021 W/cm2), representing an important step towards potential applications of TNSA-driven proton sources, especially considering that PW and even 10 PW laser facilities exist all around the world.
Oxidative stress is an important pathomechanism in psoriasis, and the Oxidative Balance Score (OBS) serves as a standardized metric for assessing systemic oxidative status, but its association with psoriasis is unclear. This study included 18,023 adults from the NHANES to investigate the relationship between OBS and psoriasis. After using a complex sampling weighting method, we performed multi-model logistic regression and stratified analysis with OBS as the exposure and psoriasis as the outcome for the primary analysis. Restricted cubic spline (RCS) plots were used to evaluate potential nonlinear associations between OBS and psoriasis. In addition, we performed replication analyses using two 24-hour dietary records data as a sensitivity test to ensure robustness of the results. Multi-model logistic regression analyses revealed no statistically meaningful link between OBS and psoriasis prevalence when accounting for all confounders (p>0.05), but in stratified analyses, OBS demonstrated a significant association with reduced risk of psoriasis in individuals aged 60–80 years (OR=0.27-0.35, p<0.05). As part of the overall OBS, moderate dietary OBS (DOBS) demonstrated an association with reduced psoriasis risk in 60-80 year olds (OR=0.39-0.43, p<0.05). Lifestyle OBS (LOBS) indicates a significant negative correlation with psoriasis risk among the “Other Hispanic” group. (Q3 OR=0.23, p<0.05). The RCS showed a non-linear relationship between LOBS and psoriasis (nonlinear P=0.013). This study provides the first systematic confirmation of an association between OBS and a reduced risk of psoriasis in elderly populations and specific ethnic groups. These findings offer new insights and directions for the prevention and treatment of psoriasis.
What determines countries’ successful transition to democracy? This article explores the impact of granting civil rights in authoritarian regimes and especially the gendered aspect of this process. It argues that both men's and women's liberal rights are essential conditions for democratisation to take place: providing both women and men rights reduces an inequality that affects half of the population, thus increasing the costs of repression and enabling the formation of women's organising – historically important to spark protests in initial phases of democratisation. This argument is tested empirically using data that cover 173 countries over the years 1900–2012 and contain more nuanced measures than commonly used. Through novel sequence analysis methods, the results suggest that in order to gain electoral democracy a country first needs to furnish civil liberties to both women and men.
The volunteer experience in organizational context has received far less scrutiny. Studies have indicated specific organizational settings, such as schedule flexibility, orientation and training, empowerment, social interaction, reflection, and rewards, and each has certain influences on their satisfaction and intention of remain. But we do not know their combined impact as organizational facilitators. This study focused on a sample of hospital volunteering, which occupies the largest service hours of volunteering work in Taiwan. We explored the experience of organizational facilitators that affect the satisfaction and loyalty of the volunteers from 868 valid questionnaires in a metropolitan hospital. The results showed that volunteers with more experiences on social interaction, reflections, and rewards, were more satisfied. In term of loyalty, volunteers with higher satisfaction showed higher willing to remain, recommend, accept services, and donate. Furthermore, because of flexible schedules and preferable rewards, the volunteers were more willing to remain; because of more training, higher social interaction, reflections, and rewards, the volunteers were more willing to recommend volunteering and accept services. Additionally, less flexible schedules, better empowerment, and more reflections as well as rewards influenced volunteers to be more motivated to donate. Implications of organizational efforts toward the hospital volunteer management are discussed.
Although deep reinforcement learning (DRL) techniques have been extensively studied in the field of robotic manipulators, there is limited research on directly mapping the output of policy functions to the joint space of manipulators. This paper proposes a motion planning scheme for redundant manipulators to avoid obstacles based on DRL, considering the actual shapes of obstacles in the environment. This scheme not only accomplishes the path planning task for the end-effector but also enables autonomous obstacle avoidance while obtaining the joint trajectories of the manipulator. First, a reinforcement learning framework based on the joint space is proposed. This framework uses the joint accelerations of the manipulator to calculate the Cartesian coordinates of the end-effector through forward kinematics, thereby performing end-to-end path planning for the end-effector. Second, the distance between all the linkages of the manipulator and irregular obstacles is calculated in real time based on the Gilbert–Johnson–Keerthi distance algorithm. The reward function containing joint acceleration is constructed with this distance to realize the obstacle avoidance task of the redundant manipulator. Finally, simulations and physical experiments were conducted on a 7-degree-of-freedom manipulator, demonstrating that the proposed scheme can generate efficient and collision-free trajectories in environments with irregular obstacles, effectively avoiding collisions.
Possibilistic logic programs (poss-programs) under stable models are a major variant of answer set programming. While its semantics (possibilistic stable models) and properties have been well investigated, the problem of inductive reasoning has not been investigated yet. This paper presents an approach to extracting poss-programs from a background program and examples (parts of intended possibilistic stable models). To this end, the notion of induction tasks is first formally defined, its properties are investigated and two algorithms ilpsm and ilpsmmin for computing induction solutions are presented. An implementation of ilpsmmin is also provided and experimental results show that when inputs are ordinary logic programs, the prototype outperforms a major inductive learning system for normal logic programs from stable models on the datasets that are randomly generated.
Acute effects of a daily dose of red wine may cause deterioration of visual function; however, there is limited information on healthy individuals. This study aims to investigate acute effects of daily red wine consumption on visual function and retinal microvasculature in healthy young adults through a randomised self-controlled design and to explore the molecular mechanisms using an animal model. In healthy young adults’ study, twenty-seven adults with follow-up at baseline, 0·5 h and 2 h after consuming 300 ml of either red wine or water underwent blood biochemistry, visual function, morphology and blood flow of retinal and choroidal vasculatures, and cerebral blood flow (CBF) evaluation. Acute red wine consumption caused abnormal changes in retinal function (multifocal visual electrophysiology) that preceded changes in vision. Macular vessel diameter index (VDI) increased significantly at 0·5 h but decreased significantly at 2 h, despite increased regional CBF following red wine consumption, which was consistent with increased choroidal thickness and decreased retinal thickness. Animal experiments conducted on Brown Norway rats demonstrated a significant decrease in retinal VDI and vessel area density (VAD) associated with increased reactive oxygen species production following red wine administration, as well as decreased endothelial nitric oxide synthase (eNOS) and increased endothelin-1 (ET-1) levels in the retina. Consequently, red wine consumption caused abnormal changes in retinal function and microvascular constriction in healthy young adults, and an animal model suggested that the underlying mechanism may involve the regulation of eNOS and ET-1 levels in the retina. These findings imply the potential detrimental effects of drinking habits on individuals with retinal ischaemic diseases.
Investigations into the effects of polymers on small-scale statistics and flow patterns were conducted in a turbulent von Kármán swirling (VKS) flow. We employed the tomographic particle image velocimetry technique to obtain full information on three-dimensional velocity data, allowing us to effectively resolve dissipation scales. Under varying Reynolds numbers ($R_\lambda =168{-}235$) and polymer concentrations ($\phi =0{-}25\ {\textrm{ppm}}$), we measured the velocity gradient tensor (VGT) and related quantities. Our findings reveal that the ensemble average and probability density function (PDF) of VGT invariants, which represent turbulent dissipation and enstrophy along with their generation terms, are suppressed as polymer concentration increases. Notably, the joint PDFs of the invariants of VGT, which characterise local flow patterns, exhibited significant changes. Specifically, the third-order invariants, especially the local vortex stretching, are greatly suppressed, and strong events of dissipation and enstrophy coexist in space. The local flow pattern tends to be two-dimensional, where the eigenvalues of the rate-of-strain tensor satisfy a ratio $1:0:-1$, and the vorticity aligns with the intermediate eigenvector of the rate-of-strain tensor, while it is perpendicular to the other two. We find that these statistics observations can be well described by the vortex sheet model. Moreover, we find that these vortex sheet structures align with the symmetry axis of the VKS system, and orient randomly in the horizontal plane. Further investigation, including flow visualisation and conditional statistics on vorticity, confirms the presence of vortex sheet structures in turbulent flows with polymer additions. Our results establish a link between single-point statistics and small-scale flow topology, shedding light on the previously overlooked small-scale structures in polymeric turbulence.
Arabinoxylans (AX), the primary hemicellulose found in cereals and grasses, play a crucial role in regulating immunity, metabolism and various physiological processes, underscoring their value as essential components in dietary nutrition. Considering the extensive research on AX in piglet nutrition, this paper systematically reviews their impacts on gut health and microbiota in piglets, as well as the underlying mechanisms of action. AX have been shown to mediate gut barrier fortification through tight junction protein upregulation and orchestrate mucosal immunity homeostasis, consequently ameliorating early-weaning-associated diarrheal pathogenesis in piglets. Additionally, AX function as microbial ecological modulators through selective enrichment of beneficial commensal microbiota (e.g. Bifidobacterium spp. and Lactobacillus spp.), while simultaneously stimulating microbial biosynthesis of SCFA and ferulic acid exhibiting potent antioxidant and anti-inflammatory activity, thereby maintaining the intestinal health of piglets. This review offers valuable insights into their potential as a dietary intervention to support gut health and immune function in early-weaned piglets. However, most studies focus on single-source AX such as wheat or maize, with limited exploration of novel sources or comparative effects of source combinations. Future research should systematically investigate the molecular mechanisms of AX action, provide data-driven guidance for selecting AX sources in feed formulations and establish optimal inclusion levels in practical feeding regimens. Such efforts will further solidify the precision nutrition potential of AX in promoting sustainable and healthy growth in piglets.
In this study, we present a low-numerical-aperture (NA) confined-doped fiber architecture that synergistically mitigates transverse mode instability (TMI) through combined optical waveguide engineering and spatially tailored gain distribution. The individual and combined benefits of low-NA fiber design and the confined-doped fiber design strategy on TMI mitigation are numerically investigated. Building upon these theoretical analyses, a self-developed fiber, featuring a core/cladding diameter of approximately 26/400 μm, a core NA of approximately 0.045 and a core doping ratio of approximately 75%, is fabricated. Further experimental validation in a master oscillator power amplifier demonstrates 6.74 kW output power with near-single-mode (M${}^2\sim$1.49) beam quality, validating the design’s efficacy. This study establishes a novel fiber design paradigm that concurrently addresses TMI mitigation, beam quality maintenance and power scalability, offering a viable pathway toward robust high-power fiber laser sources with near-diffraction-limited beam quality.
Previous studies highlighted the health benefits of coffee and tea, but they only focused on the comparisons between different consumptions. Consequently, the association estimate lacked a clear interpretation, as the substitution of beverages and distribution of doses were not explicitly prescribed. We focused on the ‘relative association’ to ascertain the optimal consumption strategy (including total intake and optimal allocation strategy) for coffee, tea and plain water associated with decreased mortality. Self-reported coffee, tea and plain water intake were used from the UK Biobank. Within a compositional data analysis framework, a multivariate Cox model was used to assess the relative associations after adjusting for a range of potential confounders. The lower mortality risk was observed with at least approximately 7–8 drinks/d of total consumption. When the total intake > 4 drinks/d, substituting plain water with coffee or tea was linked to reduced mortality; nevertheless, the benefit was not seen for ≤ 4 drinks/d. Besides, a balanced consumption of coffee and tea (roughly a ratio of 2:3) associated with the lowest hazard ratios of 0·55 (95 % CI 0·47, 0·64) for all-cause mortality, 0·59 (95 % CI 0·48, 0·72) for cancer mortality, 0·69 (95 % CI 0·49, 0·99) for CVD mortality, 0·28 (95 % CI 0·15, 0·52) for respiratory disease mortality and 0·35 (95 % CI 0·15, 0·82) for digestive disease mortality than other combinations. These results highlight the importance of the rational combination of coffee, tea and plain water, with particular emphasis on ensuring adequate total intake, offering more comprehensive and explicit guidance for individuals.
This paper examines how credit constraints shape the transmission of uncertainty shocks in business cycles. Standard models struggle to capture the simultaneous declines in output, consumption, investment, and labor hours during uncertainty spikes. We introduce collateral-based credit constraints for impatient households and entrepreneurs, linking their borrowing capacity to asset values. As uncertainty rises, higher risk premia reduce the demand for collateral assets, prompting impatient households to cut labor supply, leading to an output decline. Our model generates macroeconomic co-movements without relying on nominal rigidities. Lowering the loan-to-value (LTV) ratio, particularly for households, helps mitigate these adverse effects.
We aimed to investigate the association between plasma advanced glycation end products (AGE) level and fat, skeletal muscle-related body composition parameters in middle-aged and elderly Chinese participants. A total of 1139 participants aged over 40 years were included in a cross-sectional study. Body composition including BMI, waist:hip ratio (WHR), fat mass index (FMI), percentage of body fat (PBF), the ratio of trunk fat to legs fat (trunk fat/legs fat), fat free mass (FFM), fat free mass index (FFMI) and skeletal muscle index (SMI) was measured using a bioelectrical impedance analyser. Plasma free and combined AGE were measured by ultra-high performance liquid chromatography-tandem MS. Multiple linear regression and weighted quantile sum regression models were used to examine the association between AGE and body composition parameters. Total exposure of plasma advanced glycation end products (AGE) was positively associated with BMI (β (95 % CI): 0·381 (0·037, 0·724), P = 0·030), FMI (β (95 % CI): 0·521 (0·241, 0·800), P = 0·001), PBF (β (95 % CI): 1·996 (1·160, 2·832), P < 0·0001), trunk fat/legs fat (β (95 % CI): 0·058 (0·036, 0·080), P < 0·001); while it was negatively associated with FFM (β (95 % CI): −1·075 (–2·028, –0·122), P = 0·027), FFMI (β (95 % CI): −0·687 (–1·076, –0·297), P = 0·001) and SMI (β (95 % CI): −1·264 (–1·767, –0·761), P < 0·001). The associations between plasma AGE and FFM and FFMI were more pronounced in those aged less than 61 years and female participants. This study provides evidence on the associations between plasma AGE and fat and skeletal muscle parameters, suggesting their potential role in the development of obesity and skeletal muscle loss.
For every , we prove a $C^r$-connecting lemma for Lorenz attractors. To be precise, for a Lorenz attractor of a $3$-dimensional $C^r$ ($r\geq 2$) vector field, a heteroclinic orbit associated to the singularity and a critical element can be created through arbitrarily small $C^r$-perturbations. As an application, we show that for $C^r$-dense geometric Lorenz attractors, the Dirac measure of the singularity is isolated inside the space of ergodic measures, and thus, the ergodic measure space is not connected, while for $C^r$-generic geometric Lorenz attractors, the space of ergodic measures is path connected with dense periodic measures. In particular, the generic part proves a conjecture proposed by C. Bonatti [11, Conjecture 2] in $C^r$-topology for Lorenz attractors.
To evaluate the prognostic value of electrocardiographic ventricular repolarisation parameters in children with dilated cardiomyopathy.
Methods:
A retrospective study was conducted involving 89 children with dilated cardiomyopathy [age 5.24 (4.32, 6.15) years] as the research group, and a control group consisting of 80 healthy children matched for age and sex. Within the research group, there were 76 cases in the survival subgroup and 13 cases in the death subgroup. Ventricular repolarisation parameters were measured.
Results:
(1) Compared to the control group, both QTcmax and QTcmin were significantly prolonged in the research group (P < 0.01). Additionally, Tp-Te /QT ratios for leads III, aVL, V1, V2, and V3 showed an increase (P < 0.05), while T-wave amplitudes for leads I, II, aVL, aVF, V4, V5, and V6 exhibited a decrease (P < 0.05). (2) In comparison to the survival subgroup, the diameters of the LV, RV, LA, and RA in the death subgroup were enlarged, while the left ventricular ejection fraction and eft ventricular fractional shortening were decreased (P < 0.05). The Tp-Te /QT ratios for leads aVR, V5, and V6 also increased notably (P < 0.05 or P < 0.01). The T-wave amplitude readings from leads II, aVF, and V6 demonstrated significant reductions (P < 0.05).
Conclusion:
Abnormal ventricular repolarisation parameters were found in dilated cardiomyopathy children. Increased Tp-Te /QT ratios in aVR, V5, and V6 leads and decreased T-wave amplitudes in II, aVF, and V6 leads were risk factors for predicting mortality in children with dilated cardiomyopathy.
The aerodynamic sound generated by the oblique collision of two vortex rings is featured by the asymmetric emission associated with the octupole mode, which differs from the symmetric emission associated with the quadrupole mode observed in the coaxial collision of two vortex rings. This distinctive feature of aerodynamic sound is closely related to the tilting and reconnecting of the vortex rings. While previous studies have explored the effects of reconnecting on aerodynamic sound, this study specifically addresses the impact of vortex ring tilting. We propose a novel vortex sound formula to quantitatively assess the role of tilting in aerodynamic sound generation. The proposed formula relates the far-field sound pressure to equivalent circulations and vorticity centroids by referring to Truesdell’s consistency conditions for vorticity moments. The variations of the equivalent circulations and vorticity centroids in the oblique collision of two vortex rings under different configurations are analysed based on the numerical solution of the Navier–Stokes equations in the source region. It is found that the tilting of vortex rings results in a rapid change of the equivalent circulation associated with the vorticity in the collision direction. However, the change caused by titling is almost out of phase with that caused by reconnecting and deforming. The vortex tilting significantly reduces the aerodynamic sound associated with the longitudinal quadrupole and octupole modes, which is opposite to the role of vortex reconnecting that was reported in the oblique collision of vortex rings.