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The beam transport process plays a crucial role in the design and realization of negative-ion-based neutral beam injection (N-NBI) systems for thermonuclear fusion. In particular, space charge compensation (SCC), where positive ions generated by collisions between negative ions and background gas mitigate space charge effects, serves as a critical mechanism influencing beam divergence and envelope evolution. In this work, the SCC process in N-NBI systems and its impact on beam transport are investigated using a 3D simulation model based on a Vlasov beam-tracing algorithm. Systematic simulations show that SCC evolution and downstream beam optics are jointly controlled by background gas pressure and beam energy, with higher pressure and higher energy strengthening SCC and mitigating divergence and envelope growth downstream of the extraction system. A key physical observation is that collisionless phase mixing drives the transverse velocity distribution of secondary ions toward a Maxwellian distribution, enabling an effective transverse ion temperature that quantitatively correlates with SCC degree. The residual electric field leaking downstream of the extraction system locally weakens SCC over a finite extent, producing negligible beam optics impact for the ITER-relevant 1 MeV case at pressures of 5×10−3 Pa and 1×10−2 Pa, but non-negligible transport sensitivity at 200 keV under the same pressure range. These results provide new insight into the interplay between SCC, secondary-ion dynamics, and beam transport, with direct relevance to the modeling and optimization of high-energy NBI beamlines.

Interleukin 10 (IL‐10)‐producing B cells (B10 cells) are a canonical cell fraction for regulating other activities of immune cells. Posttranscriptional modification of IL‐10 in B10 cells is not yet fully understood. Short‐chain fatty acids play an important role to regulate the functions of immune cells. This study aims to clarify the role of propionic acid (PA), a short‐chain fatty acid, in regulating the expression of IL‐10 in B10 cells. Blood samples were collected from patients with food allergy (FA) and healthy subjects. Serum and cellular components were prepared with the samples, and analysed by enzyme‐linked immunosorbent assay and flow cytometry, respectively. The results showed that serum PA levels were lower in FA patients. PA concentrations were negatively correlated with serum cytokine Th2 concentrations, specific IgE concentrations in serum and skin prick test results. The peripheral frequency of B10 cells and the production of IL‐10 in B cells were also associated with serum PA concentrations. Activation of B cells by CpG induced the production of IL‐10 and tristetretrprolin (TTP), in which TTP caused the spontaneous decay of IL‐10 mRNA. PA was necessary to stabilize the IL‐10 mRNA in B cells by inducing the production of granzyme B, which resulted in the degradation of the IL‐10 mRNA. Administration of PA attenuated FA response in mice by maintaining homeostasis of B10 cells. In conclusion, PA is needed to stabilize the expression of IL‐10 in B10 cells. PA administration can mitigate experimental FA by maintaining B10 cell functions.

Decoupling economic activities and C[O.sub.2] emissions is central to achieving the climate goals of China. The country's participation in global value chains has profound impacts on its economy as well as C[O.sub.2] emissions. Assessing the impacts is fundamental to identifying strategies to decouple China's development from emissions. To this end, we adopt the multi-region structural decomposition analysis technique to quantify the global value chain determinants of China's C[O.sub.2] emission intensity from both the production and consumption perspectives. It is found that China's decoupling from emissions in 2007-2012 was driven mainly by global value chains. Nonetheless the decoupling slowed down after the global financial crisis. In particular, the value chains within China played a more important role in greening Chinese economy. Despite the considerable improvement in 2007-2012, global value chains remained the primary obstacle to environmental sustainability of China. More detailed results with policy implications are presented.

Objective Catheter-associated urinary tract infections (CAUTI) are common worldwide, but due to limited resources, its actual burden in low-income countries is unknown. Currently, there are gaps in knowledge about CAUTI due to lack of surveillance activities in Sierra Leone. In this prospective cohort study, we aimed to determine the incidence of CAUTI and associated antibiotic resistance in two tertiary hospitals in different regions of Sierra Leone. Results The mean age of the 459 recruited patients was 48.8 years. The majority were females (236, 51.3%). Amongst the 196 (42.6%) catheterized patients, 29 (14.8%) developed CAUTI. Bacterial growth was reported in 32 (84%) patients. Escherichia coli (14, 23.7%), Klebsiella pneumoniae (10, 17.0%), and Klebsiella oxytoca (8, 13.6%) were the most common isolates. Most isolates were ESBL-producing Enterobacteriaceae (33, 56%) and WHO Priority 1 (Critical) pathogens (38, 71%). Resistance of K. pneumoniae, K. oxytoca, E. coli , and Proteus mirabilis was higher with the third-generation cephalosporins and penicillins but lower with carbapenems, piperacillin-tazobactam and amikacin. To reduce the high incidence of CAUTI and multi-drug resistance organisms, urgent action is needed to strengthen the microbiology diagnostic services and develop and implement catheter bundles that provide clear guidance for catheter insertion, care and removal.

Abstract The concept of a “speciation continuum” has gained popularity in recent decades. It emphasizes speciation as a continuous process that may be studied by comparing contemporary population pairs that show differing levels of divergence. In their recent perspective article in Evolution, Stankowski and Ravinet provided a valuable service by formally defining the speciation continuum as a continuum of reproductive isolation, based on opinions gathered from a survey of speciation researchers. While we agree that the speciation continuum has been a useful concept to advance the understanding of the speciation process, some intrinsic limitations exist. Here, we advocate for a multivariate extension, the speciation hypercube, first proposed by Dieckmann et al. in 2004, but rarely used since. We extend the idea of the speciation cube and suggest it has strong conceptual and practical advantages over a one-dimensional model. We illustrate how the speciation hypercube can be used to visualize and compare different speciation trajectories, providing new insights into the processes and mechanisms of speciation. A key strength of the speciation hypercube is that it provides a unifying framework for speciation research, as it allows questions from apparently disparate subfields to be addressed in a single conceptual model.

Decoupling economic activities and CO₂ emissions is central to achieving the climate goals of China. The country’s participation in global value chains has profound impacts on its economy as well as CO₂ emissions. Assessing the impacts is fundamental to identifying strategies to decouple China’s development from emissions. To this end, we adopt the multi-region structural decomposition analysis technique to quantify the global value chain determinants of China’s CO₂ emission intensity from both the production and consumption perspectives. It is found that China’s decoupling from emissions in 2007–2012 was driven mainly by global value chains. Nonetheless the decoupling slowed down after the global financial crisis. In particular, the value chains within China played a more important role in greening Chinese economy. Despite the considerable improvement in 2007–2012, global value chains remained the primary obstacle to environmental sustainability of China. More detailed results with policy implications are presented.

Quantifying the driving forces behind changes in aggregate CO₂ emissions provides valuable information for supporting policy making in addressing climate change. We study this issue using the production-theoretical decomposition analysis (PDA) technique. Within a production theory framework, PDA examines CO₂ emission changes from the perspective of productive efficiency. Although regional and sectoral heterogeneities in energy consumption and emission patterns prevail, they have not been taken into account in the PDA literature. By incorporating relevant decomposition methods, this study proposes an extended PDA approach to resolving the heterogeneity issue. The approach is applied to examine China’s aggregate CO₂ emission changes in its 11th five-year plan period (2005–2010). By accounting for the heterogeneities, detailed results at the regional and sectoral levels are generated and further discussions presented.

Introduction: Despite the prolongation of hospitalization, increase in morbidity, mortality and cost of care associated with both surgical site infections (SSIs) and antibiotic resistance, there are limited data on SSIs and antibiotic resistance to guide prevention strategies in Sierra Leone. Methods: This study assessed the burden of SSIs and related antibiotic resistance in the 34 Military Hospital (MH) and Makeni Government Hospital (MGH) located in two geographic regions of Sierra Leone using a prospective study design to collect data from adults aged 18 years or older. Results: Of the 417 patients, 233 (55.9%) were enrolled in MGH. Most were women 294 (70.5%). The incidence rate of SSI was 5.5 per 1000 patient-days, and the cumulative incidence of SSI was 8.2%. Common bacteria isolated in MH were Escherichia coli (6,33.3%) and Pseudomonas aeruginosa (3,16.7%) and in MGH were P. aeruginosa (3,42.9%) and Proteus mirabilis (2,28.9%). Of the gram-negative bacteria, 40% were Extended-spectrum beta-lactamase-producing Enterobacteriaceae, 33% were Carbapenem-resistant P. aeruginosa and 10% were carbapenem-resistant Enterobacteriaceae. Conclusion: Although the incidence of SSIs in our study is lower than previously reported, the rate of antibiotic resistance reported in this study is high. Urgent action is needed to invest in the microbiology infrastructure to support SSI surveillance and prevention strategies.

Many studies have confirmed that applying positive end-expiratory pressure (PEEP) to the dependent lung during one-lung ventilation (OLV) improves oxygenation. Our purpose was to investigate the best time and level of PEEP application. Thirty patients undergoing thoracic surgery were randomised into three groups. After 20 minutes of two-lung ventilation (TL V) in the lateral position, all patients received OL V for one hour. During OLV, 0, 5, 10 cmH 2 O PEEP were applied in order in group A, with each level sustained for 20 minutes. Group B had 5 cmH 2 O PEEP applied and maintained for one hour. Patients in group C received PEEP with levels set in the opposite order to that of group A. The ventilation model was then converted to TLV.P a O 2 , P a CO 2 and respiratory mechanical variables were compared at five different time points among groups, 20 minutes after TLV (T1), 20 (T2), 40 (T3) and 60 minutes (T4) after OLV, and 20 minutes after conversion to TL V (T5). We found that P a O 2 was lower in group A than the other two groups at T2 (P <0.05). P a O 2 decreased significantly at T5 compared with T1 (P <0.05) in group A only. When PEEP was set to 10 cmH 2 O, the airway pressure increased significantly (P <0.05). These findings indicate that PEEP applied at the initial time of OLV improves oxygenation most beneficially. Five cmH 2 O PEEP may produce this beneficial effect without the increase in airway pressure associated with 10 cmH 2 O PEEP.

Novel experimental techniques are required to make the next big leap in neutron electric dipole moment experimental sensitivity, both in terms of statistics and systematic error control. The nEDM experiment at the Spallation Neutron Source (nEDM@SNS) will implement the scheme of Golub & Lamoreaux [Phys. Rep., 237, 1 (1994)]. The unique properties of combining polarized ultracold neutrons, polarized 3 He, and superfluid 4 He will be exploited to provide a sensitivity to ∼ 10 −28   e  · cm. Our cryogenic apparatus will deploy two small (3 L) measurement cells with a high density of ultracold neutrons produced and spin analyzed in situ. The electric field strength, precession time, magnetic shielding, and detected UCN number will all be enhanced compared to previous room temperature Ramsey measurements. Our 3 He co-magnetometer offers unique control of systematic effects, in particular the Bloch-Siegert induced false EDM. Furthermore, there will be two distinct measurement modes: free precession and dressed spin. This will provide an important self-check of our results. Following five years of “critical component demonstration,” our collaboration transitioned to a “large scale integration” phase in 2018. An overview of our measurement techniques, experimental design, and brief updates are described in these proceedings.