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Background Conventional right ventricular pacing (RVP) has been associated with an increased incidence of atrial fibrillation (AF). We sought to compare the occurrence of new‐onset AF and assessed AF disease progression during long‐term follow‐up between His bundle pacing (HBP) and RVP. Methods and Results We included patients undergoing initial dual‐chamber pacemaker implants at Rush University Medical Center between January 1, 2016, and June 30, 2019. A total of 360 patients were evaluated, and 225 patients (HBP, n=105; RVP, n=120) were included in the study. Among the 148 patients (HBP, n=72; RVP, n=76) with no history of AF, HBP demonstrated a lower risk of new‐onset AF (adjusted hazard ratio [HR], 0.53; 95% CI, 0.28–0.99; P=0.046) compared with traditional RVP. This benefit was observed with His or RVP burden exceeding 20% (HR, 0.29; 95% CI, 0.13–0.64; P=0.002), ≥40% (HR, 0.31; P=0.007), ≥60% (HR, 0.35; P=0.015), and ≥80% (HR, 0.40; P=0.038). There was no difference with His or RV pacing burden

Background: Access to healthcare delivery programs and systems is a primary correlate to the overall health and well-being of Veterans and the general population. Participation in clinical research is a gateway to novel therapies that are intended to address current global health issues. Meeting or exceeding recruitment goals in clinical research is one of the key determinants of the timely and successful completion of a study. The travel and time burdens experienced by study participants are often considered barriers to their enrollment into clinical research. The Department of Veterans Affairs (VA) Cooperative Studies Program (CSP) established a consortium of nine VA medical centers (VAMCs) called the Network of Dedicated Enrollment Sites (NODES). The NODES program provides study site-level expertise and innovative approaches that address challenges to clinical research execution. In alignment with our mission, our program developed an approach to increase study participant access to clinical research through implementing “Mobile Recruitment (MoRe)” units. This manuscript describes the utility and challenges associated with employing this strategy to address three common barriers to clinical research participation: 1) research participant travel burden, 2) participant access to study opportunities, and 3) low participant enrollment. Methods: A plan to introduce the Mobile Recruitment (MoRe) unit as a recruitment strategy was piloted for a high-volume, observational cohort study and mega biobank in the VA health care system, the “Million Veteran Program (MVP)”. MoRe is a recruitment strategy for CSP research integrating mobile technology and atypical research recruitment locations. Recruitment locations include primary or main VA hospitals and their assigned VA Community-Based Outpatient Clinics (CBOCs). Each Node site (n = 9) received components of the MoRe unit including a laptop, printer, portable cart with storage space, cooler/ice packs for specimen storage and transport. Each site's usage of these components varied based on its respective needs. Activities focused on both VA main facilities and CBOC facilities for recruitment. Results: Seven of the nine Node sites compared the effectiveness of the MoRe unit on MVP study enrollment outcomes over three-time points: pre-intervention period, intervention period, and post-intervention period. The utilization of MoRe in the intervention period demonstrated a 36.9% increase in enrollment compared to the previous six months (pre-intervention period). There was a 2% enrollment increase at the six-month post-intervention period as compared to the intervention period. When comparing the pre-intervention period to the post-intervention period (duration of eighteen months), enrollment increased by 38.9%. Conclusion: Five of the seven sites experienced an increase in enrollment during the intervention and post-intervention periods. The two sites without an increase in enrollment experienced various extenuating factors. Characteristics of sites using MoRe included the ability to utilize a smaller, unconventional space, i.e. not a traditional clinical research exam space for recruitment. MoRe was utilized in hospital laboratory space, CBOCs, primary care clinics, and other subspecialty clinics that allowed recruitment activities but did not have dedicated space to offer the research teams for that purpose. This initiative successfully demonstrated the benefit of deploying the unit, proving its utility in cases in where there was a lack of space or alternative workstations for research activities. The implementation of MoRe by NODES as a recruitment strategy for MVP may be transferable to other VA clinical research studies, as well as to other healthcare settings executing similar clinical research activities.

There is broad consensus that many bones of extinct vertebrates contain Rare Earth Elements (REE) and other trace minerals that have been incorporated and enriched into the fossil during diagenesis. During fossilization, apatite minerals in vertebrate bones recrystallize from metastable biogenic forms to thermodynamically more stable inorganic apatite minerals while incorporating REEs from their environment. More than ∼95% of the REE in fossil bones are diagenetically incorporated post-mortem, and bones in different environments have different and distinct REE signatures, generally viewed to be controlled by sedimentological and taphonomic processes. The REE pattern in fossils is generally stable, and the normalized concentration patterns provide unique “fingerprints” or signatures that have been used for various geological and paleontological investigations. The discovery of embryos and their adults at the same site, a previously unrecorded occurrence in the fossil record, allowed us to compare for the first time the relationship between REE concentrations in the same taxon at widely differing ontogenetic stages. Here we compare REE patterns in bones from two distinct sites in Yunnan, China, both preserving embryonic and adult bones of Early Jurassic Sauropodomorpha dinosaurs. These dinosaurs are closely related to each other and close in geological age, and their bones show very similar REE patterns. However, the embryonic bones have significantly lower levels of total REEs when compared to their adult counterparts. We attribute the 10-fold La_REE difference and U concentration 5/1 ratio to the level of ossification of the bones and the dramatically lower concentration of apatites in the embryonic than in the adult bones. We conclude that the ontogenetic stage of fossil materials can have a significant impact on REE concentrations, and discuss the impact of these results on future work.

Background Cryoballoon (CB) ablation is widely performed for pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). Anatomic variations in patient pulmonary vein (PV) anatomy are believed to impact short‐ and long‐term procedural success of CB PVI. Methods and Results We hypothesized that failure of initial PV isolation with a standard technique (ie, requiring >2 freeze cycles per PV and/or radiofrequency ablation [RFA] to achieve PV isolation) during index CB PVI procedures would be associated with decreased freedom from AF. We examined a cohort of 177 consecutive patients with drug‐refractory AF who underwent CB PVI with a 28‐mm balloon second‐generation CB device. Mean follow‐up time was 19±9 months. Forty‐three patients had AF recurrence after the 90‐day blanking period after ablation. In 40 patients, acute isolation of one or more PVs could not be achieved by CB ablation with the standard technique (single freeze with or without bonus freeze). To obtain complete acute PVI, 15 patients received extra freeze applications, 20 required supplemental RFA, and 5 received both extra freeze applications and supplemental RFA. Multivariate regression analysis revealed supplemental RFA use during index CB PVI procedures was independently associated with a threefold increased risk of AF recurrence (adjusted hazard ratio, 3.01; 1.45–10.87; P=0.003). Conclusions Use of supplemental RFA during CB PVI procedures to assist with isolation of one or more PVs was independently associated with increased risk of AF recurrence. Use of additional freezes to achieve PVI did not increase the risk for recurrent AF.

This paper describes the latest version of the algorithm MAIAC used for processing the MODIS Collection 6 data record. Since initial publication in 2011–2012, MAIAC has changed considerably to adapt to global processing and improve cloud/snow detection, aerosol retrievals and atmospheric correction of MODIS data. The main changes include (1) transition from a 25 to 1 km scale for retrieval of the spectral regression coefficient (SRC) which helped to remove occasional blockiness at 25 km scale in the aerosol optical depth (AOD) and in the surface reflectance, (2) continuous improvements of cloud detection, (3) introduction of smoke and dust tests to discriminate absorbing fine- and coarse-mode aerosols, (4) adding over-water processing, (5) general optimization of the LUT-based radiative transfer for the global processing, and others. MAIAC provides an interdisciplinary suite of atmospheric and land products, including cloud mask (CM), column water vapor (CWV), AOD at 0.47 and 0.55 µm, aerosol type (background, smoke or dust) and fine-mode fraction over water; spectral bidirectional reflectance factors (BRF), parameters of Ross-thick Li-sparse (RTLS) bidirectional reflectance distribution function (BRDF) model and instantaneous albedo. For snow-covered surfaces, we provide subpixel snow fraction and snow grain size. All products come in standard HDF4 format at 1 km resolution, except for BRF, which is also provided at 500 m resolution on a sinusoidal grid adopted by the MODIS Land team. All products are provided on per-observation basis in daily files except for the BRDF/Albedo product, which is reported every 8 days. Because MAIAC uses a time series approach, BRDF/Albedo is naturally gap-filled over land where missing values are filled-in with results from the previous retrieval. While the BRDF model is reported for MODIS Land bands 1–7 and ocean band 8, BRF is reported for both land and ocean bands 1–12. This paper focuses on MAIAC cloud detection, aerosol retrievals and atmospheric correction and describes MCD19 data products and quality assurance (QA) flags.

Aerosol–cloud interactions remain a major source of uncertainty in climate forcing estimates. Few studies have been conducted to characterize the aerosol–cloud interactions in heavily polluted conditions worldwide. In this study, cloud residual and cloud interstitial particles were collected during cloud events under different pollution levels from 22 July to 1 August 2014 at Mt. Tai (1532 m above sea level) located in the North China Plain (NCP). A transmission electron microscope was used to investigate the morphology, size, and chemical composition of individual cloud residual and cloud interstitial particles, and to study mixing properties of different aerosol components in individual particles. Our results show that S-rich particles were predominant (78 %) during clean periods (PM2.5<15 µg m−3), but a large number of anthropogenic refractory particles (e.g., soot, fly ash, and metal) and their mixtures with S-rich particles (defined as S-refractory) were observed during polluted periods. Cloud droplets collected during polluted periods were found to become an extremely complicated mixture by scavenging abundant refractory particles. We found that 76 % of cloud residual particles were S-refractory particles and that 26 % of cloud residual particles contained two or more types of refractory particles. Soot-containing particles (i.e., S-soot and S-fly ash/metal-soot) were the most abundant (62 %) among cloud residual particles, followed by fly ash/metal-containing particles (i.e., S-fly ash/metal and S-fly ash/metal-soot, 37 %). These complicated cloud droplets have not been reported in clean continental or marine air before. Our findings provide an insight into the potential impacts on cloud radiative forcing from black carbon and metal catalyzed reactions of SO2 in micro-cloud droplets containing soluble metals released from fly ash and metals over polluted air.

Background: Randomized clinical trials are the gold standard for evaluating healthcare interventions and, more generally, add to the medical knowledge related to the treatment, diagnosis and prevention of diseases and conditions. Recent literature continues to identify health informatics methods that can help improve study efficiency throughout the life cycle of a clinical trial. Electronic medical record (EMR) data provides a mechanism to facilitate clinical trial research during the study planning and execution phases, and ultimately, can be utilized to enhance recruitment. The Department of Veterans Affairs (VA) has a strong history of clinical and epidemiological research with over four decades of data collected from Veterans it has served nationwide. The VA Informatics and Computing Infrastructure (VINCI) provides VA research investigators with a nationwide view of high-value VA patient data. Within VA, the Cooperative Studies Program (CSP) Network of Dedicated Enrollment Sites (NODES) is a consortium of nine sites that are part of an embedded clinical research infrastructure intended to provide systematic site-level solutions to issues that arise during the conduct of VA CSP clinical research. This paper describes the collaboration initiated by the Salt Lake City (SLC) node site to bring informatics and clinical trials together to enhance study planning and recruitment within the VA. Methods: The SLC VA Medical Center physically houses both VINCI and a node site and the co-location of these two groups prompted a natural collaboration on both a local and national level. One of the functions of the SLC NODES is to enhance recruitment and promote the success of CSP projects. VINCI supports these efforts by providing VA researchers access to potential population pools. VINCI can provide 1) feasibility data during study planning, and 2) active patient lists during recruitment. The process for CSP study teams to utilize these services involves regulatory documentation, development of queries, revisions to the initial data request, and ongoing communications with several key study personnel including the requesting research team, study statisticians, and VINCI data managers. Results: The early efforts of SLC NODES and VINCI aimed to provide patient lists exclusively to the SLC CSP study teams for the following purposes: 1) increasing recruitment for trials that were struggling to meet their respective enrollment goals, and 2) decreasing the time required by study coordinators to complete chart review activities. This effort was expanded to include multiple CSP sites and studies. To date, SLC NODES has facilitated the delivery of these VINCI services to nine active CSP studies. Conclusion: The ability of clinical trial study teams to successfully plan and execute their respective trials is contingent upon their proficiency in obtaining data that will help them efficiently and effectively recruit and enroll eligible participants. This collaboration demonstrates that the utilization of a model that partners two distinct entities, with similar objectives, was effective in the provision of feasibility and patient lists to clinical trial study teams and facilitation of clinical trial research within a large, integrated healthcare system. Keywords: Clinical trial recruitment, Clinical informatics, Cooperative studies program (CSP), Network of dedicated enrollment sites (NODES), VA informatics and computing infrastructure (VINCI)

Introduction: Leading change effectively is critical to advancing medical education. Residency didactics often require change in order to meet stakeholder’s needs. Kotter’s change management model (KCMM) is an 8-step method for implementing change that can be applied to educational initiatives. This innovation improved an emergency medicine residency didactics curriculum through application of KCMM. Methods: An initiative to improve residency didactics curriculum was titled the “Didactics Revolution” and implemented according to KCMM: establish a sense of urgency, form a powerful guiding coalition, create a vision, communicate the vision, empower others to act on the vision, plan for and create short-term wins, consolidate improvements and produce still more change, and institutionalize new approaches. Data from the Annual Program Review was utilized to assess the impact of the KCMM strategy. Results: The percentage of residents who agreed or strongly agreed that lectures provide a valuable learning experience increased from 39.1% in the year prior to 88.0% in the year during the implementation (p < .001), and remained relatively high at 73.5% in the year following. The percentage of residents who agreed or strongly agreed that they felt well-prepared for the written boards increased from 60.9% in the year prior to 92.0% in the year during the implementation (p = .01) and remained high at 73.5% in the year following. Conclusion: Residency didactics can be improved through the use of KCMM, a change management model originally developed in the corporate context.

The formation of secondary organic aerosol (SOA) has been widely studied in the presence of dry seed particles at low relative humidity (RH). At higher RH, initially dry seed particles can exist as wet particles due to water uptake by the seeds as well as the SOA. Here, we investigated the formation of SOA from the photooxidation of toluene using an oxidation flow reactor in the absence of NOx under a range of OH exposures on initially wet or dry ammonium sulfate (AS) seed particles at an RH of 68 %. The ratio of the SOA yield on wet AS seeds to that on dry AS seeds, the relative SOA yield, decreased from 1.31 ± 0.02 at an OH exposure of 4.66 × 1010 molecules cm−3 s to 1.01 ± 0.01 at an OH exposure of 5.28 × 1011 molecules cm−3 s. This decrease may be due to the early deliquescence of initially dry AS seeds after being coated by highly oxidized toluene-derived SOA. SOA formation lowered the deliquescence RH of AS and resulted in the uptake of water by both AS and SOA. Hence the initially dry AS seeds contained aerosol liquid water (ALW) soon after SOA formed, and the SOA yield and ALW approached those of the initially wet AS seeds as OH exposure and ALW increased, especially at high OH exposure. However, a higher oxidation state of the SOA on initially wet AS seeds than that on dry AS seeds was observed at all levels of OH exposure. The difference in mass fractions of m ∕ z 29, 43 and 44 of SOA mass spectra, obtained using an aerosol mass spectrometer (AMS), indicated that SOA formed on initially wet seeds may be enriched in earlier-generation products containing carbonyl functional groups at low OH exposures and later-generation products containing acidic functional groups at high exposures. Our results suggest that inorganic dry seeds become at least partially deliquesced particles during SOA formation and hence that ALW is inevitably involved in the SOA formation at moderate RH. More laboratory experiments conducted with a wide variety of SOA precursors and inorganic seeds under different NOx and RH conditions are warranted.

This paper presents the quality journey taken by a Federal organization over more than 20 years. These efforts have resulted in the implementation of a Total Integrated Performance Excellence System (TIPES) that combines key principles and practices of established quality systems. The Center has progressively integrated quality system frameworks including the Malcom Baldrige National Quality Award (MBNQA) Framework and Criteria for Performance Excellence, ISO 9001, and the Organizational Project Management Maturity Model (OPM3), as well as supplemental quality systems of ISO 15378 (packaging for medicinal products) and ISO 21500 (guide to project management) to systematically improve all areas of operations. These frameworks were selected for applicability to Center processes and systems, consistency and reinforcement of complimentary approaches, and international acceptance. External validations include the MBNQA, the highest quality award in the US, continued registration and conformance to ISO standards and guidelines, and multiple VA and state awards. With a focus on a holistic approach to quality involving processes, systems and personnel, this paper presents activities and lessons that were critical to building TIPES and establishing the quality environment for conducting clinical research in support of Veterans and national health care.

Real density and powder resistivity are key indicators for the quality of calcined petroleum coke (CPC). They are closely related to calcining parameters in shaft calciner. Fuzzy grey relational analysis was proposed to evaluate the effects of various factors (discharge rate per pot (DR), flue wall temperature of layers 2 (T2) and 8 (T8), volatiles (V), ash (A) and sulfur content (S) of green petroleum coke) on the quality of CPC. Results showed that by order of influence degree (most to least) to the real density, the factors were ranked as T2, V, DR, T8, A, and S, and for the powder resistivity, they were ranked as V, T2, DR, T8, and S.

Background: Approximately 697,000 members of the U.S. Armed Forces were deployed to the Persian Gulf in support of the 1990–1991 Persian Gulf War (GW). Subsequently, many deployed and some non-deployed veterans developed a chronic multi-symptom illness, now named Gulf War Illness (GWI). This manuscript outlines the methods and rationale for studying the genomics of GWI within the Million Veteran Program (MVP), a VA-based national research program that has linked medical records, surveys, and genomic data, enabling genome-wide association studies (GWASs). Methods: MVP participants who served in the military during the GW era were contacted by mail and invited to participate in the GWI study. A structured health questionnaire, based on a previously tested instrument, was also included in the mailing. Data on deployment locations and exposures, symptoms associated with GWI, clinical diagnoses, personal habits, and health care utilization were collected. Self-reported data will be augmented with chart reviews and structured international classification of disease codes, to classify participants by GWI case status. We will develop a phenotyping algorithm, based on two commonly used case definitions, to determine GWI status, and then conduct a nested case-control GWAS. Genetic variants associated with GWI will be investigated, and gene–gene and gene–environment interactions studied. The genetic overlap of GWI with, and causative mechanisms linking this illness to, other health conditions and the effects of genomic regulatory mechanisms on GWI risk will also be explored. Conclusions: The proposed initial GWAS described in this report will investigate the genomic underpinnings of GWI with a large sample size and state-of-the-art genomic analyses and phenotyping. The data generated will provide a rich and expansive foundation on which to build additional analyses.

In performance-based seismic design, ground-motion time histories are needed for analyzing dynamic responses of nonlinear structural systems. However, the number of ground-motion data at design level is often limited. In order to analyze seismic performance of structures, ground-motion time histories need to be either selected from recorded strong-motion database or numerically simulated using stochastic approaches. In this paper, a detailed procedure to select proper acceleration time histories from the Next Generation Attenuation (NGA) database for several cities in Taiwan is presented. Target response spectra are initially determined based on a local ground-motion prediction equation under representative deterministic seismic hazard analyses. Then several suites of ground motions are selected for these cities using the Design Ground Motion Library (DGML), a recently proposed interactive ground-motion selection tool. The selected time histories are representatives of the regional seismic hazard and should be beneficial to earthquake studies when comprehensive seismic hazard assessments and site investigations are unavailable. Note that this method is also applicable to site-specific motion selections with the target spectra near the ground surface considering the site effect.

Through investigation and analysis of geological conditions and mechanical parameters of the Tazihping landslide, finite-volume method coupling with Voellmy model is used to simulate the landslide mass movement process. The present paper adopts the numerical approach of the RAMMS software program and the GIS platform to simulate the mass movement process before and after engineering treatment. This paper also provides the conditions and characteristic variables of flow-type landslide in terms of flow height, velocity, and stresses. The 3-D division of hazard zones before and after engineering treatment was also mapped. The results indicate that the scope of hazard zones decreased after engineering treatment of the landslide. Compared with the case of before engineering treatment, the extent of high-hazard zones was reduced by about two-thirds, and the characteristic variables of the mass movement in the case of after treatment decreased to one-third of those in the case of before treatment. Despite having engineering treatment, the Tazhiping landslide still poses significant potential threat to the nearby residences. Therefore, it suggests that the houses located in high-hazard zones should be relocated or reinforced for protection.

Abstract Background Evaluation of repetitive transcranial magnetic stimulation (rTMS) for treatment-resistant major depression (TRMD) in Veterans offers unique clinical trial challenges. Here we describe a randomized, double-blinded, intent-to-treat, two-arm, superiority parallel design, a multicenter study funded by the Cooperative Studies Program (CSP No. 556) of the US Department of Veterans Affairs. Methods We recruited medical providers with clinical expertise in treating TRMD at nine Veterans Affairs (VA) medical centers as the trial local investigators. We plan to enroll 360 Veterans diagnosed with TRMD at the nine VA medical centers over a 3-year period. We will randomize participants into a double-blinded clinical trial to left prefrontal rTMS treatment or to sham (control) rTMS treatment (180 participants each group) for up to 30 treatment sessions. All participants will meet Diagnostic and statistical manual of mental disorders, 4 th edition (DSM-IV) criteria for major depression and will have failed at least two prior pharmacological interventions. In contrast with other rTMS clinical trials, we will not exclude Veterans with posttraumatic stress disorder (PTSD) or history of substance abuse and we will obtain detailed history regarding these disorders. Furthermore, we will maintain participants on stable anti-depressant medication throughout the trial. We will evaluate all participants on a wide variety of potential predictors of treatment response including cognitive, psychological and functional parameters. Discussion The primary dependent measure will be remission rate (Hamilton Rating Scale for Depression (HRSD24) ≤ 10), and secondary analyses will be conducted on other indices. Comparisons between the rTMS and the sham groups will be made at the end of the acute treatment phase to test the primary hypothesis. The unique challenges to performing such a large technically challenging clinical trial with Veterans and potential avenues for improvement of the design in future trials will be described. Trial registration ClinicalTrials.gov, NCT01191333 . Registered on 26 August 2010. This report is based on the protocol version 4.6 amended in February 2016. All items from the World Health Organization Trial Registration Data Set are listed in Appendix A.

Background: Recruitment into clinical trials remains a key determinant to study completion and success. While various strategies have been proposed, it is unclear how they apply across different populations, diseases, and/or study goals. The ability to effectively overcome challenges may require different approaches that more broadly focus on addressing obstacles among sites that cannot be overcome by individual studies. Methods: The Department of Veterans Affairs (VA) Cooperative Studies Program (CSP) established the Network of Dedicated Enrollment Sites (NODES) as a consortium of sites to generate systematic site-level solutions to more efficiently recruit in CSP studies. Initial activities identified priorities and developed approaches through team-based efforts. Metrics were also developed to assess overall network performance. Results: Network efforts produced several new strategies and best practices for common problems in CSP research. Recruitment strategies included bringing studies to patients and developing data programs using algorithms for finding eligible patients. Efficiency efforts focused on cross-training and standardizing performance reports. Conclusion: NODES addressed site challenges in clinical trial recruitment and management by taking an overall approach that looked at the system rather than individual studies. Practices and operational changes were implemented for CSP research related to recruitment, staff training and research methodology. The network activities suggest that team-based development of tools and insights may help better identify targets and increase efficiencies for clinical trials recruitment.

Molecular recognition is an important biological process where guest and host molecules interact through non-covalent bonding. Yeet al. show that this can be sensed by the dielectric and ferroelectric signals of the final complexes in a series of metal-coordination compounds with different diol molecules.

The seasonal mean and synoptic fluctuation of the wintertime Taiwan Warm Current (TWC) were investigated using a well-validated finite volume community ocean model. The spatial distribution and dynamics of the synoptic fluctuation were highlighted. The seasonal mean of the wintertime TWC has two branches: an inshore branch between the 30 and 100 m isobaths and an offshore branch between the 100 and 200 m isobaths. The Coriolis term is much larger than the inertia term and is almost balanced by the pressure gradient term in both branches, indicating geostrophic balance of the mean current. Two areas with significant fluctuations of the TWC were identified during wintertime. One of the areas is located to the north of Taiwan with velocities varying in the cross-shore direction. These significant cross-shore fluctuations are driven by barotropic pressure gradients associated with the intrusion of the Taiwan Strait Current (TSC). When a strong TSC intrudes to the north of Taiwan, the isobaric slope tilts downward from south to north, leading to a cross-shore current from the coastal area to the offshore area. When the TSC intrusion is weak, the cross-shore current to the north of Taiwan is directed from offshore to inshore. The other area of significant fluctuation is located in the inshore area between the 30 and 100 m isobaths. The fluctuations are generally strong both in the alongshore and cross-shore directions, in particular at the latitudes 26.5 and 28° N. Wind affects the synoptic fluctuation through episodic events. When the northeasterly monsoon prevails, the southwestward Zhe-Min coastal current dominates the inshore area associated with a deepening of the mixed layer. When the winter monsoon is weakened or the southwesterly wind prevails, the northeastward TWC dominates in the inshore area.

Biomolecules are rarely preserved during fossilization. Here, Lee and colleagues provide evidence of collagen preserved within the 195-million-year-old rib of a sauropodomorph dinosaur usingin situanalyses and suggest that haematite particles may have contributed to protein preservation.

This paper proposes the use of microplates as a new flow control device to suppress boundary layer separation on blades and thus improve the aerodynamic performance of a low-speed axial flow fan. A computational study is performed by means of computational fluid dynamics (CFD) simulations. Numerical investigations are carried out based on Reynolds-averaged Navier-Stokes (RANS) method. The shear stress transport (SST) turbulence model and high-quality computational grids are adopted for CFD simulations. An exhaustive comparison of the fans with and without control has been conducted in terms of characteristic curves, streamlines and pressure distributions. The purpose of this work is to better understand the underlying flow control mechanisms of microplates. It is found that the total efficiency is slightly lowered when the controlled fan operates at the design flow rate. However, as the flow rate changes, the total efficiency of the controlled fan varies more gently than the original fan without control. Traced streamlines show that flow separation on blade surfaces is effectively controlled and radial flow migration on the suction surface is evidently diminished. Numerical results indicate that microplates significantly alleviate fan stall and have considerable beneficial effects on fan performance.

In this paper, the aerodynamic and mechanical design of a centripetal-flow fan has been undertaken at a particular thermal environment in which the working fluid behaves as an ideal gas. A preliminary design (one-dimensional analysis) study was conducted at first, based on which three-dimensional modeling and optimization were subsequently applied to the design of the centripetal-flow fan. The aerodynamic performance of the designed fan and its operating characteristics in different working conditions were assessed by means of numerical simulations. Our results suggest that isentropic efficiency and pressure ratio of the centripetal-flow fan at design operating conditions can reach 81.14% and 1.0833, respectively, which satisfy the requirements for fans in commercial and industrial applications. From the fan performance curves, it is found that as the mass flow rate increases, the efficiency of the fan operating at the designed rotational speed first increases and then decreases. There exists an optimal mass flow rate which leads to the maximum efficiency of the fan. Similarly, the fan pressure ratio first increases as the mass flow rate increases, attains a maximum value and then decreases as the mass flow rate further increases. At off-design rotational speeds, although the fan characteristic curves show the same tendency as those observed at the design condition. Moreover, the fan characteristic curve becomes steeper with an increased rotational speed, which means that the variations of isentropic efficiency and pressure ratio with change in mass flow rate become much greater. The results of our present study confirm the feasibility of using the centripetal-flow fan for various industrial applications.

Measurements at particle collider experiments, even if primarily aimed at understanding Standard Model processes, can have a high degree of model independence, and implicitly contain information about potential contributions from physics beyond the Standard Model. The Contur package allows users to benefit from the hundreds of measurements preserved in the Rivet library to test new models against the bank of LHC measurements to date. This method has proven to be very effective in several recent publications from the Contur team, but ultimately, for this approach to be successful, the authors believe that the Contur tool needs to be accessible to the wider high energy physics community. As such, this manual accompanies the first user-facing version: Contur v2. It describes the design choices that have been made, as well as detailing pitfalls and common issues to avoid. The authors hope that with the help of this documentation, external groups will be able to run their own Contur studies, for example when proposing a new model, or pitching a new search.

The planar Hall effect (PHE), wherein a rotating magnetic field in the plane of a sample induces oscillating transverse voltage, has recently garnered attention in a wide range of topological metals and insulators. The observed twofold oscillations in ρ_{yx} as the magnetic field completes one rotation are the result of chiral, orbital, and/or spin effects. The antiperovskites A_{3}BO (A=Ca, Sr, Ba; B=Sn, Pb) are topological crystalline insulators whose low-energy excitations are described by a generalized Dirac equation for fermions with total angular momentum J=3/2. We report unusual sixfold oscillations in the PHE of Sr_{3}SnO, which persisted nearly up to room temperature. Multiple harmonics (twofold, fourfold, and sixfold), which exhibited distinct field and temperature dependencies, were detected in ρ_{xx} and ρ_{yx}. These observations are more diverse than those in other Dirac and Weyl semimetals and point to a richer interplay of microscopic processes underlying the PHE in the antiperovskites.

Catheter-based ablation techniques have a well-established role in atrial fibrillation (AF) management. The prevalence and impact of AF is increasing globally, thus mandating an emphasis on improving ablation techniques through innovation. One key area of ongoing evolution in this field is the use of laser energy to perform pulmonary vein isolation during AF catheter ablation. While laser use is not as widespread as other ablation techniques, such as radiofrequency ablation and cryoballoon ablation, advancements in product design and procedural protocols have demonstrated laser balloon ablation to be equally safe and effective compared to these other modalities. Additionally, strategies to improve procedural efficiency and decrease radiation exposure through low fluoroscopy protocols make this technology an increasingly promising and exciting option.

Episodes with high concentrations of particulate matter (PM) across the seasons were investigated during four 1-month campaigns at a suburban site in Hong Kong. High-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) measurements revealed that both regional transport and secondary formation contributed to high PM levels during the episodes at this site. Based on distinct meteorological conditions, episodes were categorized into three types: liquid water content (LWC), solar irradiance (IR), and long-range transport (LRT). Despite the difference in meteorological conditions, all episodes were characterized by a high fraction of sulfate (45–56 %) and organics (23–34 %). However, aerosols in LWC episodes were less aged, consisting of the lowest fraction of secondary organic aerosol (SOA) and the highest fraction of small particles. Large particles mixed internally while freshly formed small particles mixed externally in LWC episodes. Aerosols in LRT episodes, by contrast, were the most aged and consisted of the highest proportion of low-volatility oxygenated organic aerosol (LVOOA) and the lowest proportion of small particles. Both small and large particles mixed externally in LRT episodes. The highest proportion of semi-volatile oxygenated organic aerosol (SVOOA) and a medium proportion of small particles were observed in IR episodes. Both small and large particles were likely externally mixed during IR episodes. Furthermore, aerosols experienced the most dramatic size increase and diurnal variation, with a time lag between SVOOA and LVOOA and a gradual increase in carbon oxidation state (OSc ≈ 2 × O : C − H : C). Five out of 10 episodes were of the IR type, further reflecting the importance of this type of episode. The evolution of aerosol components in one particular episode of the IR type, which exhibited a clear land–sea breeze pattern, was examined in detail. Sulfate and SOA due to photochemical aging were very efficiently produced during the course of 6 h. The “less-oxidized” SOA (SVOOA) was initially formed at a higher rate than the “more-oxidized” SOA (LVOOA). The SVOOA transformed to LVOOA at the later stage of photochemical aging. This transformation was further supported by mass spectral analysis, which showed an increase in the most oxidized ion (CO2+) and decreases in moderately oxidized ones (C2H3O+, C3H3O+ and C3H5O+). By measuring the physical and chemical properties of PM in a highly time-resolved manner, the current study was able to demonstrate the dynamic and complex nature of PM transformation during high-PM episodes.

Integrated multi-trophic aquaculture (IMTA) involves the farming of species from different trophic positions or nutritional levels in the same system. In China, IMTA has been practiced for many decades, with dozens of species farmed in close proximity to each other at the scale of whole coastal bays. Articles in this Theme Section present results from the MoST-China Project on ‘Sustainability of Marine Ecosystem Production under Multi-stressors and Adaptive Management’ (2011-2015). This project sought to understand the interactions between biogeochemical cycles and ecosystem function in the IMTA system of Sanggou Bay, China, which produces a total of >240000 t of seafood each year from >30 species in approximately 100 km2 of production space. Results include measurements of carbon, nitrogen flow and trophic relationships among cultured species; impacts of IMTA on benthic nutrient fluxes, reduced inorganic sulfur in sediments, distribution of dissolved inorganic selenium, and nutrient cycling; distribution and seasonal variation of picoplankton; and a model for kelp growth. Combined, the articles enable a complex understanding of the dynamics between IMTA and the environment in one of the most important coastal aquaculture production systems in the world.

Organic peroxides, important species in the atmosphere, promote secondary organic aerosol (SOA) aging, affect HOx radicals cycling, and cause adverse health effects. However, the formation, gas-particle partitioning, and evolution of organic peroxides are complicated and still unclear. In this study, we investigated in the laboratory the production and gas-particle partitioning of peroxides from the ozonolysis of α-pinene, which is one of the major biogenic volatile organic compounds in the atmosphere and an important precursor for SOA at a global scale. We have determined the molar yields of hydrogen peroxide (H2O2), hydromethyl hydroperoxide (HMHP), peroxyformic acid (PFA), peroxyacetic acid (PAA), and total peroxides (TPOs, including unknown peroxides) and the fraction of peroxides in α-pinene/O3 SOA. Comparing the gas-phase peroxides with the particle-phase peroxides, we find that gas-particle partitioning coefficients of PFA and PAA are 104 times higher than the values from the theoretical prediction, indicating that organic peroxides play a more important role in SOA formation than previously expected. Here, the partitioning coefficients of TPO were determined to be as high as (2–3) × 10−4 m3 µg−1. Even so, more than 80 % of the peroxides formed in the reaction remain in the gas phase. Water changes the distribution of gaseous peroxides, while it does not affect the total amount of peroxides in either the gas or the particle phase. Approx. 18 % of gaseous peroxides undergo rapid heterogeneous decomposition on SOA particles in the presence of water vapor, resulting in the additional production of H2O2. This process can partially explain the unexpectedly high H2O2 yields under wet conditions. Transformation of organic peroxides to H2O2 also preserves OH in the atmosphere, helping to improve the understanding of OH cycling.

Non-refractory submicron aerosol is characterized using an Aerosol Chemical Speciation Monitor (ACSM) in the fall and winter seasons of 2013 on the roadside in an Asian megacity environment in Hong Kong. Organic aerosol (OA), characterized by application of Positive Matrix Factorization (PMF), and sulfate are found to be dominant. Traffic-related organic aerosol shows good correlation with other vehicle-related species, and cooking aerosol displays clear mealtime concentration maxima and association with surface winds from restaurant areas. Contributions of individual species and OA factors to high NR-PM1 are analyzed for hourly data and daily data; while cooking emissions in OA contribute to high hourly concentrations, particularly during mealtimes, secondary organic aerosol components are responsible for episodic events and high day-to-day PM concentrations. Clean periods are either associated with precipitation, which reduces secondary OA with a lesser impact on primary organics, or clean oceanic air masses with reduced long-range transport and better dilution of local pollution. Haze events are connected with increases in contribution of secondary organic aerosol, from 30 to 50 % among total non-refractory organics, and the influence of continental air masses.

Marine protected areas (MPAs) are established to conserve species, but the extent to which they also conserve evolutionary history is not clear. Here, Mouillot et al. show that for tropical corals and fish, the current global MPA network secures only 1.7 and 17.6% of phylogenetic diversity, respectively.