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Abstract Background Disease recurrence remains one of the biggest concerns in patients after resection of pancreatic ductal adenocarcinoma (PDAC). Despite (neo)adjuvant systemic therapy, most patients experience local and/or distant PDAC recurrence within 2 years. High-level evidence regarding the benefits of recurrence-focused surveillance after PDAC resection is missing, and the impact of early detection and treatment of recurrence on survival and quality of life is unknown. In most European countries, recurrence-focused follow-up after surgery for PDAC is currently lacking. Consequently, guidelines regarding postoperative surveillance are based on expert opinion and other low-level evidence. The recent emergence of more potent local and systemic treatment options for PDAC recurrence has increased interest in early diagnosis. To determine whether early detection and treatment of recurrence can lead to improved survival and quality of life, we designed an international randomized trial. Methods This randomized controlled trial is nested within an existing prospective cohort in pancreatic cancer centers in the Netherlands (Dutch Pancreatic Cancer Project; PACAP) and the United Kingdom (UK) (Pancreas Cancer: Observations of Practice and survival; PACOPS) according to the “Trials within Cohorts” (TwiCs) design. All PACAP/PACOPS participants with a macroscopically radical resection (R0-R1) of histologically confirmed PDAC, who provided informed consent for TwiCs and participation in quality of life questionnaires, are included. Participants randomized to the intervention arm are offered recurrence-focused surveillance, existing of clinical evaluation, serum cancer antigen (CA) 19–9 testing, and contrast-enhanced computed tomography (CT) of chest and abdomen every three months during the first 2 years after surgery. Participants in the control arm of the study will undergo non-standardized clinical follow-up, generally consisting of clinical follow-up with imaging and serum tumor marker testing only in case of onset of symptoms, according to local practice in the participating hospital. The primary endpoint is overall survival. Secondary endpoints include quality of life, patterns of recurrence, compliance to and costs of recurrence-focused follow-up, and the impact on recurrence-focused treatment. Discussion The RADAR-PANC trial will be the first randomized controlled trial to generate high level evidence for the current clinical equipoise regarding the value of recurrence-focused postoperative surveillance with serial tumor marker testing and routine imaging in patients after PDAC resection. The Trials within Cohort design allows us to study the acceptability of recurrence-focused surveillance among cohort participants and increases the generalizability of findings to the general population. While it is strongly encouraged to offer all trial participants treatment at time of recurrence diagnosis, type and timing of treatment will be determined through shared decision-making. This might reduce the potential survival benefits of recurrence-focused surveillance, although insights into the impact on patients’ quality of life will be obtained. Trial registration Clinicaltrials.gov, NCT04875325 . Registered on May 6, 2021.

In this article, we introduce spyro, a software stack to solve wave propagation in heterogeneous domains and perform full waveform inversion (FWI) employing the finite-element framework from Firedrake, a high-level Python package for the automated solution of partial differential equations using the finite-element method. The capability of the software is demonstrated by using a continuous Galerkin approach to perform FWI for seismic velocity model building, considering realistic geophysics examples. A time domain FWI approach that uses meshes composed of variably sized triangular elements to discretize the domain is detailed. To resolve both the forward and adjoint-state equations and to calculate a mesh-independent gradient associated with the FWI process, a fully explicit, variable higher-order (up to degree k=5 in 2D and k=3 in 3D) mass-lumping method is used. We show that, by adapting the triangular elements to the expected peak source frequency and properties of the wave field (e.g., local P-wave speed) and by leveraging higher-order basis functions, the number of degrees of freedom necessary to discretize the domain can be reduced. Results from wave simulations and FWIs in both 2D and 3D highlight our developments and demonstrate the benefits and challenges with using triangular meshes adapted to the material properties.

This paper details and tests numerical improvements to the ADvanced CIRCulation (ADCIRC) model, a widely used finite-element method shallow-water equation solver, to more accurately and efficiently model global storm tides with seamless local mesh refinement in storm landfall locations. The sensitivity to global unstructured mesh design was investigated using automatically generated triangular meshes with a global minimum element size (MinEle) that ranged from 1.5 to 6 km. We demonstrate that refining resolution based on topographic seabed gradients and employing a MinEle less than 3 km are important for the global accuracy of the simulated astronomical tide. Our recommended global mesh design (MinEle = 1.5 km) based on these results was locally refined down to two separate MinEle values (500 and 150 m) at the coastal landfall locations of two intense storms (Hurricane Katrina and Super Typhoon Haiyan) to demonstrate the model's capability for coastal storm tide simulations and to test the sensitivity to local mesh refinement. Simulated maximum storm tide elevations closely follow the lower envelope of observed high-water marks (HWMs) measured near the coast. In general, peak storm tide elevations along the open coast are decreased, and the timing of the peak occurs later with local coastal mesh refinement. However, this mesh refinement only has a significant positive impact on HWM errors in straits and inlets narrower than the MinEle and in bays and lakes separated from the ocean by these passages. Lastly, we demonstrate that the computational performance of the new numerical treatment is 1 to 2 orders of magnitude faster than studies using previous ADCIRC versions because gravity-wave-based stability constraints are removed, allowing for larger computational time steps.

Background Perioperative use of statins is reported to improve postoperative outcomes after cardiac and non‐cardiovascular surgery. The aim of this study was to investigate the influence of statins on postoperative outcomes including complications of grade IIIa and above, posthepatectomy liver failure (PHLF), and 90‐day mortality rates after liver resection. Methods Patients who underwent hepatectomy between 2013 and 2017 were reviewed to identify statin users and non‐users (controls). Propensity matching was conducted for age, BMI, type of surgery and preoperative co‐morbidities to compare subgroups. Univariable and multivariable analyses were performed for the following outcomes: 90‐day mortality, significant postoperative complications and PHLF. Results Of 890 patients who had liver resection during the study period, 162 (18·2 per cent) were taking perioperative statins. Propensity analysis selected two matched groups, each comprising 154 patients. Overall, 81 patients (9·1 per cent) developed complications of grade IIIa or above, and the 90‐day mortality rate was 3·4 per cent (30 patients), with no statistically significant difference when the groups were compared before and after matching. The rate of PHLF was significantly lower in patients on perioperative statins than in those not taking statins (10·5 versus 17·3 per cent respectively; P = 0·033); similar results were found after propensity matching (10·4 versus 20·8 per cent respectively; P = 0·026). Conclusion The rate of PHLF was significantly lower in patients taking perioperative statins, but there was no statistically significant difference in severe complications and mortality rates.

Background Early treatment is the only potential cure for periampullary cancer. The pathway to surgery is complex and involves multiple procedures across local and specialist hospitals. The aim of this study was to analyse variability within this pathway, and its impact on cost and outcomes. Methods Patients undergoing surgery for periampullary cancer (2011–2016) were identified retrospectively and their pathway to surgery was analysed. Patients who had early surgery (shortest quartile, Q1) were compared with those having late surgery (longest quartile, Q4). Results A total of 483 patients were included in the study, with 121 and 124 patients in Q1 and Q4 respectively. The median time from initial CT to surgery was 21 days for Q1 versus 112 days for Q4 (P

OceanMesh2D is a set of MATLAB functions with preprocessing and post-processing utilities to generate two-dimensional (2-D) unstructured meshes for coastal ocean circulation models. Mesh resolution is controlled according to a variety of feature-driven geometric and topo-bathymetric functions. Mesh generation is achieved through a force balance algorithm to locate vertices and a number of topological improvement strategies aimed at improving the worst-case triangle quality. The placement of vertices along the mesh boundary is adapted automatically according to the mesh size function, eliminating the need for contour simplification algorithms. The software expresses the mesh design and generation process via an objected-oriented framework that facilitates efficient workflows that are flexible and automatic. This paper illustrates the various capabilities of the software and demonstrates its utility in realistic applications by producing high-quality, multiscale, unstructured meshes.

Parenting quality is important in child development. In the presence of HIV poverty and life stress, parenting may be challenged and child development affected. This study examines cross-sectional associations of situational factors such as poverty, mental health, HIV status, living with a biological parent, and stigma with good parenting and child outcomes (n = 989; age = 4–13 years) within the Child Community Care study (South Africa and Malawi). A parenting measure was created from 10 variables comprising 6 child and 4 parent ratings. These were highly correlated. Total parenting score was generated on a 10-point continuous scale, with a good parenting cut-off then defined as ≥8 out of a possible 10. Five factors were associated with good parenting. Positively associated with good parenting were being the biological parent of the child, parental mental health and dwelling in households with multiple adults. Poverty and stigma were negatively associated with good parenting. Using multiple mediation analysis, a positive direct effect of good parenting was found on child self-esteem, child behaviour and educational risks with a partial mediation via child depression and trauma. These data highlight possible intervention points. Influences on parenting could be seen through being the biological parent, parental mental health, poverty and stigma. In these challenging environments, health, nutrition, mental health, education and treatment to keep parents alive are all clearly identified as potential pathways to ensure child well-being.

Inspired by the scar‐free wound healing in infants, an anti‐scar strategy is proposed by accelerating wound healing using silicate bioactive materials. Bioglass/alginate composite hydrogels are applied, which significantly inhibit scar formation in rabbit ear scar models. The underlining mechanisms include stimulation of Integrin Subunit Alpha 2 expression in dermal fibroblasts to accelerate wound healing, and induction of apoptosis of hypertrophic scar fibroblasts by directly stimulating the N‐Acylsphingosine Amidohydrolase 2 expression in hypertrophic scar fibroblasts, and indirectly upregulating the secretion of Cathepsin K in dermal fibroblasts. Considering specific functions of the bioactive silicate materials, two scar treatment regimes are tested. For severe scars, a regenerative intervention is applied by surgical removal of the scar followed by the treatment with bioactive hydrogels to reduce the formation of scars by activating dermal fibroblasts. For mild scars, the bioactive dressing is applied on the formed scar and reduces scar by inducing scar fibroblasts apoptosis. [ABSTRACT FROM AUTHOR]

Radiation injuries, particularly those resulting from therapeutic or accidental exposure, present complex challenges for medical management. These injuries can manifest localized skin damage or extend to deeper tissues, presenting as various clinical entities that require treatment strategies, ranging from conservative management to complex surgical interventions. Radiation treatment constitutes a fundamental component of neoplastic management, with nearly two out of three oncological instances undergoing it as an element of their therapeutic strategy. The therapeutic approach to radiation injury consists of expanding prophylactic measures while maintaining the efficacy of treatment, such as conservative treatment or local debridement followed by reconstruction. The armamentarium of reconstructive methods available for plastic surgeons, from secondary healing to free tissue transfer, can be successfully applied to radiation injuries. However, the unique pathophysiological changes induced by radiation necessitate a careful and specialized approach for their application, considering the altered tissue characteristics and healing dynamics. The therapeutic strategy is guided by both the severity and progression of the injury, with the primary aim of restoring functionality and aesthetic aspects while simultaneously minimizing the risk of complications. This paper explores the various conditions encompassed by the term "radiation injury," reviews both non-surgical and surgical therapeutic strategies for managing these injuries, and highlights the unique challenges associated with treating irradiated tissues within specific oncological contexts. [ABSTRACT FROM AUTHOR]

The human primary visual cortex (V1) development is pivotal to understanding cortical maturation and neuroplasticity. Theories on V1 development range from early maturation models, which emphasize the early peak of synapses in infancy, to those suggesting an extended developmental timeline where key plasticity mechanisms continue to mature well into adulthood. Classic histological approaches have supported early development, while recent molecular studies highlight prolonged or multiple windows of plasticity, indicating that V1 remains susceptible to experience-dependent modifications beyond childhood. This review consolidates findings from both anatomical and molecular studies, tracing the development of V1 from prenatal stages through aging. The evidence reveals that human V1 develops across multiple timescales, with some aspects maturing early and others gradually changing across the lifespan. Reflecting on Cajal’s early work, this review underscores the importance of methodological advancements in revealing the intricate details of V1’s development. [ABSTRACT FROM AUTHOR]

The aerosol–cloud–precipitation interactions within the cloud-topped marine boundary layer (MBL) are examined using aircraft in situ measurements from Aerosol and Cloud Experiments in the Eastern North Atlantic (ACE-ENA) and Southern Ocean Clouds, Radiation, Aerosol Transport Experimental Study (SOCRATES) field campaigns. SOCRATES clouds exhibit a larger number concentration and smaller cloud droplet effective radius (148.3 cm-3 and 8.0 µm) compared to ACE-ENA summertime (89.4 cm-3 and 9.0 µm) and wintertime clouds (70.6 cm-3 and 9.8 µm). The ACE-ENA clouds, especially during the winter, feature stronger drizzle formation via droplet growth through enhanced collision–coalescence that is attributed to a relatively cleaner environment and deeper cloud layer. Furthermore, the aerosol–cloud interaction (ACI) indices from the two aircraft field campaigns exhibit distinct sensitivities, indicating different cloud microphysical responses to aerosols. The ACE-ENA winter season features relatively fewer aerosols, which are more likely activated into cloud droplets under the conditions of sufficient water vapor availability and strong turbulence. The enriched aerosol loading during ACE-ENA summer and SOCRATES generally leads to smaller cloud droplets competing for the limited water vapor and exhibiting a stronger ACI. Notably, the precipitation susceptibilities are stronger during the ACE-ENA than during the SOCRATES campaigns. The in-cloud drizzle behavior significantly alters sub-cloud cloud condensation nuclei (CCN) budgets through the coalescence-scavenging effect and, in turn, impacts the ACI assessments. The results of this study can enhance understanding and aid in future model simulation and assessment of the aerosol–cloud interaction. [ABSTRACT FROM AUTHOR]

Oral delivery of proteins faces challenges due to the harsh conditions of the gastrointestinal (GI) tract, including gastric acid and intestinal enzyme degradation. Permeation enhancers are limited in their ability to deliver proteins with high molecular weight and can potentially cause toxicity by opening tight junctions. To overcome these challenges, we propose the use of montmorillonite (MMT) as an adjuvant that possesses both inflammation-oriented abilities and the ability to regulate gut microbiota. This adjuvant can be used as a universal protein oral delivery technology by fusing with advantageous binding amino acid sequences. We demonstrated that anti-TNF-α nanobody (VII) can be intercalated into the MMT interlayer space. The carboxylate groups (-COOH) of aspartic acid (D) and glutamic acid (E) interact with the MMT surface through electrostatic interactions with sodium ions (Na+). The amino groups (NH2) of asparagine (N) and glutamine (Q) are primarily attracted to the MMT layers through hydrogen bonding with oxygen atoms on the surface. This binding mechanism protects VII from degradation and ensures its release in the intestinal tract, as well as retaining biological activity, leading to significantly enhanced therapeutic effects on colitis. Furthermore, VII@MMT increases the abundance of short-chain fatty acids (SCFAs)-producing strains, including Clostridia, Prevotellaceae, Alloprevotella, Oscillospiraceae, Clostridia_vadinBB60_group, and Ruminococcaceae, therefore enhance the production of SCFAs and butyrate, inducing regulatory T cells (Tregs) production to modulate local and systemic immune homeostasis. Overall, the MMT adjuvant provides a promising universal strategy for protein oral delivery by rational designed protein. [ABSTRACT FROM AUTHOR]

Cloud seeding involves boosting precipitation by releasing substances into the air that act as cloud condensation or ice nuclei. These substances encourage the development of clouds and precipitation. It's like giving Mother Nature a gentle push to assist with rainfall in specific areas. The current work aimed to suggest Al2O3 as an alternate compound in cloud seeding rather than silver iodide. In this research, a unique approach is used to identify condensation nuclei, which play a crucial role in cloud formation and droplet growth. Various samples and four sources were included in the current study; refrigerated helfa powder, Himalayan salt, generator powder, and pollen, were analyzed using different physicochemical instruments. The proportions of chemical compounds in the samples show that there is 1.392% of Al2O3 in Refrigerated helfa which is the highest than in the other 3 sources, while the proportions of elements in the samples indicate that refrigerated helfa contains the lowest toxic compound, and although Al2O3 is insoluble in water, it is hygroscopic and can absorb 6.4% of humidity within 24 hours. As for the surface tension, refrigerated helfa shows lower density and surface tension than the other three sources with values of 0.9480 and 47.89 respectively. Al2O3 shows high humid absorptivity and refrigerated helfa can be used as a main source for Al2O3 which has a low effect on biota and is recommended for use in cloud seeding. However further work is recommended to be carried out in using Al2O3 as an alternative compound to silver iodide in cloud seeding. [ABSTRACT FROM AUTHOR]

Cryptochromes (CRYs), which are signaling proteins related to DNA photolyases, play pivotal roles in sensory responses throughout biology, including growth and development, metabolic regulation, circadian rhythm entrainment and geomagnetic field sensing. This review explores the evolutionary relationships and functional diversity of cryptochromes from the perspective of their molecular structures. In general, CRY biological activities derive from their core structural architecture, which is based on a Photolyase Homology Region (PHR) and a more variable and functionally specific Cryptochrome C-terminal Extension (CCE). The α/β and a-helical domains within the PHR bind FAD, modulate redox reactive residues, accommodate antenna cofactors, recognize small molecules and provide conformationally responsive interaction surfaces for a range of partners. CCEs add structural complexity and divergence, and in doing so, influence photoreceptor reactivity and tailor function. Primary and secondary pockets within the PHR bind myriad moieties and collaborate with the CCEs to tune recognition properties and propagate chemical changes to downstream partners. For some CRYs, changes in homo and hetero-oligomerization couple to light-induced conformational changes, for others, changes in posttranslational modifications couple to cascades of protein interactions with partners and effectors. The structural exploration of cryptochromes underscores how a broad family of signaling proteins with close relationship to light-dependent enzymes achieves a wide range of activities through conservation of key structural and chemical properties upon which function-specific features are elaborated. [ABSTRACT FROM AUTHOR]

Mate choice is posited to explain the evolution and maintenance of numerous secondary sexual traits, including ornamentation. This study explores the role of ornamentation in the mating success of two sister-species of wolf spider with divergent ornamentation. Mature male Schizocosa crassipalpata lack ornamentation while males of its closest living relative, S. bilineata, express both dark pigmentation and foreleg brushes. Following phenotypic manipulations of foreleg ornamentation - i.e. adding ornamentation in the form of dark pigment to non-ornamented males (S. crassipalpata, Aim 1) and removing ornamentation in varying degrees from highly ornamented males (S. bilineata, Aim 2 - shaving brushes; Aim 3 - shaving brushes and painting over dark pigment in vibration present/absent environments) - we found no evidence that ornamentation alone improves male mating success in either species, regardless of the vibratory signaling environment. In both S. bilineata experiments, however, higher courtship rates resulted in higher mating success, suggesting selection for courtship performance. Furthermore, females were more likely to turn, a presumed receptivity display, in response to males that courted at a higher rate. Also, similar to findings in another relative (S. stridulans), we found indications that ornamentation may function to ease a male's reliance on courtship performance - i.e., at low courtship rates, only ornamented males can secure a mating. Our phenotypic manipulations also influenced courtship behavior in S. bilineata. Shaved males began courting earlier and courted more often over a longer time than intact males, yet ultimately acquired similar matings. This increased courtship effort likely compensated for reduced ornamentation. Finally, the vibratory environment appears crucial for female-male dialogue in S. bilineata, as vibratory absent environments resulted in increased female attacks and decreased male courtship rates. Together, our data suggest that S. crassipalpata females do not possess a preference for ornamentation and that S. bilineata females do not use ornamentation alone in mating decisions. Instead, our results are consistent with a hypothesis that ornamentation in Schizocosa evolved, and is likely maintained, due to its interactions with dynamic movement displays (i.e. leg movements), which can themselves be plastically altered based on the signaler's phenotype as well as the signaling environment. [ABSTRACT FROM AUTHOR]

​​​​​​​This study compares aerosol mixing-state parameters obtained via simultaneous measurements using DMA–CCNC, H(/V)TDMA, and DMA–SP2, shedding light on the impacts of primary aerosol emissions and secondary aerosol (SA) formation. The analysis reveals significant variations in mixing-state parameters among different techniques, with VTDMA and DMA–SP2 indicating that non-volatile particles mainly stem from black carbon (BC)-containing aerosols, while a substantial proportion of nearly hydrophobic aerosols originates from fossil fuel combustion and biomass-burning emissions. Synthesizing the results, some nearly hydrophobic BC-free particles were found to be cloud condensation nuclei (CCN)-inactive under the measured supersaturated conditions, likely from fossil fuel combustion emissions, while others were CCN-active, linked to biomass-burning emissions. Moreover, BC-containing aerosols emitted from fossil fuel combustion exhibit more external mixing with other aerosol components compared to those from biomass burning. Secondary nitrate and organic aerosol formation significantly affect aerosol mixing states, enhancing aerosol hygroscopicity and volatility while reducing heterogeneity among techniques. The study also highlights distinct physical properties of two resolved secondary organic aerosol factors, hinting at their formation through different mechanisms. These findings underscore the importance of comparing aerosol mixing states from different techniques as a tool for understanding aerosol physical properties from different sources and their responses to SA formation, as well as aiding in the exploration of SA formation mechanisms. [ABSTRACT FROM AUTHOR]

The psychological impact of medical care accessibility during the pandemic has been widely studied, but little attention has been given to Asian immigrants in Canada. This study aimed to fill this literature gap by using a cross-sectional survey, which aimed to evaluate the impact of the COVID-19 pandemic on Chinese immigrants in North America during the second wave of the pandemic. The study focused on Chinese immigrants aged 16 or older in Canada. Covariates included sociodemographic variables, delayed access to medical care (i.e., treatment or health assessment), and other COVID-19 related variables. We used logistic LASSO regression for model selection and multivariate logistic regression models to evaluate the association between delayed access to treatment/health assessment and psychological distress outcome, as measured by the COVID-19 Peritraumatic Distress Index (CPDI). Missing data were handled using multiple imputation. Our study included 746 respondents, with 47.18% in the normal CPDI group and 36.82% in the mild-to-severe CPDI group. Most respondents were originally from Mainland China and residing in Ontario. Over half have stayed in Canada for at least 15 years. The multivariate logistic regression models identified significant risk predictors of psychological distress status: delayed access to medical care (OR = 1.362, 95% CI: 1.078–1.720, p = 0.0095), fear of COVID-19 (OR = 1.604, 95% CI: 1.293–1.989, p < 0.0001), and social loneliness (OR = 1.408, 95%CI: 1.314–1.508, p < 0.0001). Sociodemographic variables and other COVID-19-related variates did not significantly impact the study's outcome. Our findings shed light on the importance of timely medical care access to psychological well-being among Chinese Canadians. Reliable health information, mental health support, and virtual care tailored to immigrants should be considered to mitigate this impact and promote their overall health and well-being. [ABSTRACT FROM AUTHOR]

Tumor heterogeneity, the presence of multiple distinct subpopulations of cancer cells between patients or among the same tumors, poses a major challenge to current targeted therapies. The way these different subpopulations interact among themselves and the stromal niche environment, and how such interactions affect cancer stem cell behavior has remained largely unknown. Here, it is shown that an FGF‐BMP7‐INHBA signaling positive feedback loop integrates interactions among different cell populations, including mammary gland stem cells, luminal epithelial and stromal fibroblast niche components not only in organ regeneration but also, with certain modifications, in cancer progression. The reciprocal dependence of basal stem cells and luminal epithelium is based on basal‐derived BMP7 and luminal‐derived INHBA, which promote their respective expansion, and is regulated by stromal‐epithelial FGF signaling. Targeting this interaction loop, for example, by reducing the function of one or more of its components, inhibits organ regeneration and breast cancer progression. The results have profound implications for overcoming drug resistance because of tumor heterogeneity in future targeted therapies. [ABSTRACT FROM AUTHOR]

Background: The clinical impact of washed microbiota transplantation (WMT) from healthy donors in sleep disorder (SD) patients is unclear. This study aimed to investigate the effect of WMT in SD patients. Methods: The clinical data were collected from patients with different indications receiving 1-3 courses of WMT, divided into two groups by 7 points of PSQI scale. The score of PQSI and SF-36 scale was used to assess the improvement in sleep quality and life quality among patients with sleep disorders following WMT. Finally, 16S rRNA gene amplicon sequencing was performed on fecal samples of patients with sleep disorders before and after WMT. Results: WMT significantly improved sleep quality in patients with sleep disorder in the short and medium term. WMT significantly improved sleep latency, sleep time and total score in the short term. WMT significantly improved sleep quality and total score in the medium term. In terms of sleep quality and sleep latency, the improvement value also increased with the increase of treatment course, and the improvement effect of multiple treatment course was better than that of single and double treatment course. In the total score, the improvement effect of double and multiple treatment was better than that of single treatment. WMT also improved quality of life in the sleep disorder group. WMT significantly improved general health, vitality, social function and mental health in the short term. WMT significantly improved role-physical, general health, vitality, and mental health in the medium term. WMT regulated the disturbed gut microbiota in patients with sleep disorders. In the normal sleep group, WMT had no effect on the decline of sleep quality in the short, medium and long term, and had an improving effect on the quality of life. Conclusion: WMT could significantly improve sleep quality and life quality in patients with sleep disorders with no adverse events. The improvement in sleep quality resulting from WMT could lead to an overall enhancement in life quality. WMT could be a potentially effective treatment for patients with sleep disorders by regulating the gut microbiota. [ABSTRACT FROM AUTHOR]

Background: Disease recurrence remains one of the biggest concerns in patients after resection of pancreatic ductal adenocarcinoma (PDAC). Despite (neo)adjuvant systemic therapy, most patients experience local and/or distant PDAC recurrence within 2 years. High-level evidence regarding the benefits of recurrence-focused surveillance after PDAC resection is missing, and the impact of early detection and treatment of recurrence on survival and quality of life is unknown. In most European countries, recurrence-focused follow-up after surgery for PDAC is currently lacking. Consequently, guidelines regarding postoperative surveillance are based on expert opinion and other low-level evidence. The recent emergence of more potent local and systemic treatment options for PDAC recurrence has increased interest in early diagnosis. To determine whether early detection and treatment of recurrence can lead to improved survival and quality of life, we designed an international randomized trial. Methods: This randomized controlled trial is nested within an existing prospective cohort in pancreatic cancer centers in the Netherlands (Dutch Pancreatic Cancer Project; PACAP) and the United Kingdom (UK) (Pancreas Cancer: Observations of Practice and survival; PACOPS) according to the "Trials within Cohorts" (TwiCs) design. All PACAP/PACOPS participants with a macroscopically radical resection (R0-R1) of histologically confirmed PDAC, who provided informed consent for TwiCs and participation in quality of life questionnaires, are included. Participants randomized to the intervention arm are offered recurrence-focused surveillance, existing of clinical evaluation, serum cancer antigen (CA) 19–9 testing, and contrast-enhanced computed tomography (CT) of chest and abdomen every three months during the first 2 years after surgery. Participants in the control arm of the study will undergo non-standardized clinical follow-up, generally consisting of clinical follow-up with imaging and serum tumor marker testing only in case of onset of symptoms, according to local practice in the participating hospital. The primary endpoint is overall survival. Secondary endpoints include quality of life, patterns of recurrence, compliance to and costs of recurrence-focused follow-up, and the impact on recurrence-focused treatment. Discussion: The RADAR-PANC trial will be the first randomized controlled trial to generate high level evidence for the current clinical equipoise regarding the value of recurrence-focused postoperative surveillance with serial tumor marker testing and routine imaging in patients after PDAC resection. The Trials within Cohort design allows us to study the acceptability of recurrence-focused surveillance among cohort participants and increases the generalizability of findings to the general population. While it is strongly encouraged to offer all trial participants treatment at time of recurrence diagnosis, type and timing of treatment will be determined through shared decision-making. This might reduce the potential survival benefits of recurrence-focused surveillance, although insights into the impact on patients' quality of life will be obtained. Trial registration: Clinicaltrials.gov, NCT04875325. Registered on May 6, 2021. [ABSTRACT FROM AUTHOR]

Operando studies using high‐energy X‐rays from synchrotron sources are essential for unraveling the complex material transformation that electrocatalysts undergo under operating conditions. This article explores key considerations to perform these experiments and the insights gained from such studies on nanostructured electrocatalysts. Critical factors include optimizing electrochemical performance while obtaining high‐quality X‐ray signals, which often require compromises. The electrochemical operando cell design is crucial, and several different cells are discussed here. Working electrode geometries parallel to the X‐ray beam, probed with a microfocused beam, are emerging as promising solutions for realistic electrochemical performance in operando cells. Careful attention must also be paid to the electrochemical measuring conditions, electrode loading, and beam damage to ensure reliable experiments. When carefully performed and by combining multiple characterization techniques, operando studies with high‐energy X‐rays offer the unique possibility to fully understand the structure of the active electrocatalyst. [ABSTRACT FROM AUTHOR]

Antarctica and the Southern Ocean (SO) are the most pristine areas of the globe and represent ideal places to investigate aerosol–climate interactions in an unperturbed atmosphere. In this study, we present submicrometer aerosol (PM 1) source apportionment for two sample sets collected in parallel at the British Antarctic Survey stations of Signy and Halley during the austral summer of 2018–2019. Water-soluble organic matter (WSOM) is a major aerosol component at both sites (37 % and 29 % of water-soluble PM 1 , on average, at Signy and Halley, respectively). Remarkable differences between pelagic (open-ocean) and sympagic (influenced by sea ice) air mass histories and related aerosol sources are found. The application of factor analysis techniques to series of spectra obtained by means of proton-nuclear magnetic resonance (H-NMR) spectroscopy on the samples allows the identification of five organic aerosol (OA) sources: two primary organic aerosol (POA) types, characterized by sugars, polyols, and degradation products of lipids and associated with open-ocean and sympagic/coastal waters, respectively; two secondary organic aerosol (SOA) types, one enriched in methanesulfonic acid (MSA) and dimethylamine (DMA) and associated with pelagic waters and the other characterized by trimethylamine (TMA) and linked to sympagic environments; and a fifth component of unclear origin, possibly associated with the atmospheric aging of primary emissions. Overall, our results strongly indicate that the emissions from sympagic and pelagic ecosystems affect the variability in the submicrometer aerosol composition in the study area, with atmospheric circulation establishing marked latitudinal gradients only for some of the aerosol components (e.g., the sympagic components) while distributing the others (e.g., pelagic and/or aged components) both in maritime and inner Antarctic regions. [ABSTRACT FROM AUTHOR]

Cancer is a serious health problem, with a rising trend in its occurrence documented globally. Female breast cancer is the most common type of cancer worldwide with treatment consisting of different strategies like mastectomy, chemotherapy, and radiotherapy. Anticancer property has been studied in withaferin-A (WA), a bioactive compound of Withania somnifera. Another natural substance derived from bees, propolis, has been investigated for many beneficial effects on human diseases. The current study aims to investigate the ameliorative efficacy and antiproliferative potential of combinational drug therapy of withaferin-A and propolis on breast cancer cells. By evaluating the levels of glycoproteins, nucleic acids, and the marker enzymes in benzo[a]pyrene-induced breast cancer-bearing female Wistar rats, the pharmacodynamic effects of withaferin-A and propolis drug combination were examined. Biochemical analysis of DNA, RNA, and protein levels in the liver demonstrated typical results after propolis therapy. Withaferin-A and propolis drug combination treatment significantly decreased nucleic acid synthesis, indicating that combination chemotherapy has increased breast tumoricidal efficiency. The pharmacological combination therapy exhibited the capacity to control glycoproteins associated with tumor growth (hexose, hexosamine, and sialic acid), with a considerable decrease in their levels detected. Histopathological analysis of the mammary glands demonstrated a decrease in hyperplasia and cell proliferation, indicating that the treatment has the ability to reverse architectural and morphological abnormalities associated with breast cancer. This study found that natural drug compounds in combination have shown regenerative and regulating effects when given to rats carrying the breast cancer gene. [ABSTRACT FROM AUTHOR]

Accounting for the condensation of organic vapors along with water vapor (co-condensation) has been shown in adiabatic cloud parcel model (CPM) simulations to enhance the number of aerosol particles that activate to form cloud droplets. The boreal forest is an important source of biogenic organic vapors, but the role of these vapors in co-condensation has not been systematically investigated. In this work, the environmental conditions under which strong co-condensation-driven cloud droplet number enhancements would be expected over the boreal biome are identified. Recent measurement technology, specifically the Filter Inlet for Gases and AEROsols (FIGAERO) coupled to an iodide-adduct chemical ionization mass spectrometer (I-CIMS), is utilized to construct volatility distributions of the boreal atmospheric organics. Then, a suite of CPM simulations initialized with a comprehensive set of concurrent aerosol observations collected in the boreal forest of Finland during spring 2014 is performed. The degree to which co-condensation impacts droplet formation in the model is shown to be dependent on the initialization of temperature, relative humidity, updraft velocity, aerosol size distribution, organic vapor concentration, and the volatility distribution. The predicted median enhancements in cloud droplet number concentration (CDNC) due to accounting for the co-condensation of water and organics fall on average between 16 % and 22 %. This corresponds to activating particles 10–16 nm smaller in dry diameter that would otherwise remain as interstitial aerosol. The highest CDNC enhancements (Δ CDNC) are predicted in the presence of a nascent ultrafine aerosol mode with a geometric mean diameter of ∼ 40 nm and no clear Hoppel minimum, indicative of pristine environments with a source of ultrafine particles (e.g., via new particle formation processes). Such aerosol size distributions are observed 30 %–40 % of the time in the studied boreal forest environment in spring and fall when new particle formation frequency is the highest. To evaluate the frequencies with which such distributions are experienced by an Earth system model over the whole boreal biome, 5 years of UK Earth System Model (UKESM1) simulations are further used. The frequencies are substantially lower than those observed at the boreal forest measurement site (< 6 % of the time), and the positive values, peaking in spring, are modeled only over Fennoscandia and the western parts of Siberia. Overall, the similarities in the size distributions between observed and modeled (UKESM1) are limited, which would limit the ability of this model, or any model with a similar aerosol representation, to project the climate relevance of co-condensation over the boreal forest. For the critical aerosol size distribution regime, Δ CDNC is shown to be sensitive to the concentrations of semi-volatile and some intermediate-volatility organic compounds (SVOCs and IVOCs), especially when the overall particle surface area is low. The magnitudes of Δ CDNC remain less affected by the more volatile vapors such as formic acid and extremely low- and low-volatility organic compounds (ELVOCs and LVOCs). The reasons for this are that most volatile organic vapors condense inefficiently due to their high volatility below the cloud base, and the concentrations of LVOCs and ELVOCs are too low to gain significant concentrations of soluble mass to reduce the critical supersaturations enough for droplet activation to occur. A reduction in the critical supersaturation caused by organic condensation emerges as the main driver of the modeled Δ CDNC. The results highlight the potential significance of co-condensation in pristine boreal environments close to sources of fresh ultrafine particles. For accurate predictions of co-condensation effects on CDNC, also in larger-scale models, an accurate representation of the aerosol size distribution is critical. Further studies targeted at finding observational evidence and constraints for co-condensation in the field are encouraged. [ABSTRACT FROM AUTHOR]

The membrane protein Niemann-Pick type C1 (NPC1, named NCR1 in yeast) is central to sterol homeostasis in eukaryotes. Saccharomyces cerevisiae NCR1 is localized to the vacuolar membrane, where it is suggested to carry sterols across the protective glycocalyx and deposit them into the vacuolar membrane. However, documentation of a vacuolar glycocalyx in fungi is lacking, and the mechanism for sterol translocation has remained unclear. Here, we provide evidence supporting the presence of a glycocalyx in isolated S. cerevisiae vacuoles and report four cryo-EM structures of NCR1 in two distinct conformations, named tense and relaxed. These two conformations illustrate the movement of sterols through a tunnel formed by the luminal domains, thus bypassing the barrier presented by the glycocalyx. Based on these structures and on comparison with other members of the Resistance-Nodulation-Division (RND) superfamily, we propose a transport model that links changes in the luminal domains with a cycle of protonation and deprotonation within the transmembrane region of the protein. Our model suggests that NPC proteins work by a generalized RND mechanism where the proton motive force drives conformational changes in the transmembrane domains that are allosterically coupled to luminal/extracellular domains to promote sterol transport. [ABSTRACT FROM AUTHOR]

The aim of the work detailed here has been to assess the influence of the spatial locations of small towns on their functional structure. Relevant analysis involves 7 regions of Poland, with a total of 91 small towns representing two types of location category, i.e. within metropolitan areas or with a peripheral location. More specifically, research carried out used two means achieving functional classification, using either structural/hierarchical or morphological/functional analysis. Results emerged as confirming initial assumptions on the socio-economic functions small urban localities play as a reflection of their locations. In general, towns in metropolitan locations serve functions beyond purely local ones and display a specialised economic structure within which residential and industrial functions prevail. In turn, the functional structure of towns in peripheral locations emerges as highly diversified, with the role in supplying local functions also proving more significant in this case. Overall, the differences between the so-called metropolitan and peripheral small towns are seen to arise more from their level in the hierarchy than from economic structure as such. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to assess the effect of aging and alumina-particle air abrasion at different pressures on the bond strength of two luting composites to a translucent 3Y-TZP zirconia. Materials and Methods: Half of the 192 disk-shaped zirconia specimens were aged in an autoclave (group A) for 20 h (134°C, 2 bar), and the other half was not aged (group N). For each group, a different surface treatment was applied: as-sintered (group SIN), alumina-particle air abrasion either at 1 bar (group 1B) or at 2.5 bar (group 2.5B). Disks were bonded to Plexiglas tubes filled with composite resin using a phosphate monomer-based luting composite (group SA) or with a separate phosphate monomer containing primer before using a phosphate-monomer-free luting composite (group V5). All specimens were subjected to tensile bond strength testing (TBS) before and after thermocycling. Results: There were no statistically significant differences caused by autoclave aging for the test groups before thermocycling, except for the A-SIN-SA group, where the TBS decreased significantly. The variation of the aluminaparticle air abrasion pressure showed no statistically significant effect, except in the N-1B-V5 group, where TBS was significantly lower than N-2.5B-V5. After thermocycling, the TBS of most groups decreased significantly. Specimens of the primer group, which were abraded at 1 bar, showed a significant decrease in TBS in comparison with alumina-particle air abrasion at 2.5 bar. Conclusion: Twenty hours of autoclave aging had almost no influence on the bond strength of the test groups. For the primer/resin bonding system, higher pressure during alumina-particle air abrasion might help obtain a higher and more durable bond strength to zirconia. [ABSTRACT FROM AUTHOR]

Introduction: Environmental sensitivity is defined as the ability to perceive and process internal and external information. Previous studies have suggested that mental health-related factors differ by sensitivity level. This study aimed to investigate whether environmental sensitivity moderates the associations between cognitive emotion regulation strategies (e.g., rumination and blaming others) and mental health. Materials and methods: In this three-wave longitudinal study, participants (N = 1,233, 585, and 349 at Times 1, 2, and 3, respectively) completed the Cognitive Emotion Regulation Questionnaire-short and Kessler 10 scale at all the measurement points as well as the 10-item version of the Highly Sensitive Person scale and some covariates only at Time 1. Results: Latent growth model analyses indicated that the blaming others strategy had contrastive effects on changes in mental health by sensitivity level; the increase in refocusing on planning was associated with improved mental health over time only for highly sensitive individuals; and the rumination and catastrophizing strategies were the most important risk factors for mental health problems, although their effects differed slightly by sensitivity level. Conclusion: The associations between some of the cognitive strategies and mental health differ by environmental sensitivity level. Future investigations based on individual differences in sensitivity could provide innovative insights into practices. [ABSTRACT FROM AUTHOR]

Oral diseases affect nearly half of the global population throughout their lifetime causing pain, as estimated by the World Health Organization. Preservation of vital pulp is the therapeutic core as well as a challenge to protect natural teeth. Current bottleneck lies in that the regenerative capacity of injured pulp is undetermined. In this study, we identified a lifelong lineage that is labelled by cathepsin K (Ctsk) contributing to the physiological, reactionary and reparative odontogenesis of mouse molars. Ctsk + cell-mediated dentin formation is regulated by nociceptive nerve-derived Sonic Hedgehog (Shh), especially rapidly responsive to acute injury. Notably, exogenous Shh protein to the injury pulp can preserve Ctsk + cell capacity of odontogenesis for the nearby crown pulp and even remote root apex growth, alleviating conventionally developmental arrest in youth pulpitis. Exposed to chronical attrition, aged pulp Ctsk + cells still hold the capacity to respond to acute stimuli and promote reparative odontogenesis, also enhanced by exogenous Shh capping. Therefore, Ctsk + cells may be one of the lineages for accelerating precision medicine for efficient pulp treatment across ages. Shh application can be a candidate for vital pulp preservation and pulp injury repair by promoting regenerative odontogenesis to a certain extent from young adults to older individuals., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Introduction: As captured by the individual trait of Sensory Processing Sensitivity (SPS), highly sensitive children perceive, process, and responds more strongly to stimuli. This increased sensitivity may make more demanding the process of regulating and managing emotions. Yet, developmental psychology literature also showed that other variables, as those related to the rearing environment, are likely to contribute to the process of regulating emotions. With the current contribution, we aim to bridge two lines of research, that of attachment studies and that of SPS, by investigating the additive and interactive contribution of SPS and internal working models of attachment representations on emotion regulation competencies in school-aged children. Method: Participants were N = 118 Italian children (mean age: 6.5, SD = 0.58 years, and 51.8% female) with their mothers. Children's positive attachment representations were rated observationally through the Manchester Child Attachment Story Task procedure during an individual session at school. Mothers reported on children SPS trait and emotion regulation competencies completing the Highly Sensitive Child Scale-parent report and the Emotion Regulation Checklist. We performed and compared a series of main and interaction effect models. Results: SPS was not directly associated with emotion regulation but it was significantly associated with positive attachment representations in predicting emotion regulation. Highly sensitive children showed poorer emotion regulation when the internalized representations were low in maternal warmth and responsiveness. When driven by sensitive and empathic attachment representation, highly sensitive children showed better emotion regulation than less-sensitive peers, suggesting a for better and for worse effect. Discussion: Highly sensitive children are not only more vulnerable to adversities but also show better emotion regulation competencies when supported by positive internal working models of attachment relationships. Overall, findings shed light on the link between SPS and attachment and suggest that working for promoting secure attachment relationships in parent-child dyads may promote better emotion regulation competences, particularly in highly sensitive children. [ABSTRACT FROM AUTHOR]

Drugs that modulate the GABAA receptor are widely used in clinical practice for both the long-term management of epilepsy and emergency seizure control. In addition to older medications that have well-defined roles for the treatment of epilepsy, recent discoveries into the structure and function of the GABAA receptor have led to the development of newer compounds designed to maximise therapeutic benefit whilst minimising adverse effects, and whose position within the epilepsy pharmacologic armamentarium is still emerging. Drugs that modulate the GABAA receptor will remain a cornerstone of epilepsy management for the foreseeable future and, in this article, we provide an overview of the mechanisms and clinical efficacy of both established and emerging pharmacotherapies. [ABSTRACT FROM AUTHOR]

Speech rate reduction is a global speech therapy approach for speech deficits in Parkinson's disease (PD) that has the potential to result in changes across multiple speech subsystems. While the overall goal of rate reduction is usually improvements in speech intelligibility, not all people with PD benefit from this approach. Speech rate is often targeted as a means of improving articulatory precision, though less is known about rate-induced changes in other speech subsystems that could help or hinder communication. The purpose of this study was to quantify phonatory changes associated with speech rate modification across a broad range of speech rates from very slow to very fast in talkers with and without PD. Four speaker groups participated: younger and older healthy controls, and people with PD with and without deep brain stimulation of the subthalamic nucleus (STN-DBS). Talkers read aloud standardized sentences at 7 speech rates elicited using magnitude production: habitual, three slower rates, and three faster rates. Acoustic measures of speech intensity, cepstral peak prominence, and fundamental frequency were measured as a function of speech rate and group. Overall, slower rates of speech were associated with differential effects on phonation across the four groups. While all talkers spoke at a lower pitch in slow speech, younger talkers showed increases in speech intensity and cepstral peak prominence, while talkers with PD and STN-DBS showed the reverse pattern. Talkers with PD without STN-DBS and older healthy controls behaved in between these two extremes. At faster rates, all groups uniformly demonstrated increases in cepstral peak prominence. While speech rate reductions are intended to promote positive changes in articulation to compensate for speech deficits in dysarthria, the present results highlight that undesirable changes may be invoked across other subsystems, such as at the laryngeal level. In particular, talkers with STN-DBS, who often demonstrate speech deterioration following DBS surgery, demonstrated more phonatory detriments at slowed speech rates. Findings have implications for speech rate candidacy considerations and speech motor control processes in PD. [ABSTRACT FROM AUTHOR]

Water activity (aw) and interfacial energy or surface tension (σ) are key thermodynamic parameters to describe the hygroscopic growth of atmospheric aerosol particles and their ability to serve as cloud condensation nuclei (CCN), thus influencing the hydrological cycle and climate. Due to size effects and complex mixing states, however, these parameters are not well constrained for nanoparticles composed of organic and inorganic compounds in aqueous solution. In this study, we determined aw and σ by differential Köhler analysis (DKA) of hygroscopic growth measurement data for aerosol particles smaller than 100 nm composed of aqueous ammonium sulfate (AS), D-glucose (Gl), and their mixtures. High-precision measurements of hygroscopic growth were performed at relative humidities (denoted RH) ranging from 2.0 % to 99.6 % with a high-humidity tandem differential mobility analyzer (HHTDMA) in three complementary modes of operation: hydration, dehydration, and restructuring. The restructuring mode (hydration followed by dehydration) enabled the transformation of initially irregular particles into compact globules and the determination of mass equivalent diameters. The HHTDMA-derived growth factors complemented by DKA allows for determination of water activity and surface tension from dilute to highly supersaturated aqueous solutions that are not accessible with other methods. Thus, for mixed AS / Gl nanoparticles with mass ratios of 4:1 and 1:1 , the upper limit of solute mass fraction (Xs) was 0.92 and 0.98, respectively. For pure AS and Gl, the DKA-derived aw is in good agreement with electrodynamic balance and bulk measurement data. For AS particles, our aw data also agree well with the Extended Aerosol Inorganics Model (E-AIM III) over the entire concentration range. In contrast, the UNIFAC model as a part of AIOMFAC (Zuend et al., 2011) was found to overestimate aw in aqueous Gl particles, which can be attributed to unaccounted intermolecular interactions. For mixed AS and Gl nanoparticles, we observed a non-monotonic concentration dependence of the surface tension that does not follow the predictions by modeling approaches constructed for mixed inorganic/organic systems. Thus, AS / Gl particles with a 1:1 mass ratio exhibited a strong decrease of σ with increasing solute mass fraction, a minimum value of 56.5 mNm-1 at Xs≈0.5 , and a reverse trend of increasing σ at higher concentrations. We suggest that D-glucose molecules surrounded by ammonium sulfate ions tend to associate, forming non-polar aggregates, which lowers the surface tension at the air–droplet interface. We analyzed the uncertainty in the DKA-derived water activity and surface tension, related to the instrumental errors as well as to the morphology of the nanoparticles and their phase state. Our studies have shown that under optimal modes of operation of HHTDMA for moderate aqueous concentrations, the uncertainty in aw and σ does not exceed 0.2 %–0.4 % and 3 %–4 %, respectively, but it increases by an order of magnitude in the case of highly concentrated nanodroplet solutions. [ABSTRACT FROM AUTHOR]

Background: Antibiotics prescribed as infection prophylaxis prior to dental procedures have the potential for serious adverse drug events (ADEs). However, the extent to which guideline concordance and different dental settings are associated with ADEs from antibiotic prophylaxis is unknown. Aim: The purpose was to assess guideline concordance and antibiotic-associated ADEs and whether it differs by VA and non-VA settings. Methods: Retrospective cohort study of antibiotic prophylaxis prescribed to adults with cardiac conditions or prosthetic joints from 2015 to 2017. Multivariable logistic regression models were fit to assess the impact of ADEs, guideline concordance and dental setting. An interaction term of concordance and dental setting evaluated whether the relationship between ADEs and concordance differed by setting. Results: From 2015 to 2017, 61,124 patients with antibiotic prophylaxis were identified with 62 (0.1%) having an ADE. Of those with guideline concordance, 18 (0.09%) had an ADE while 44 (0.1%) of those with a discordant antibiotic had an ADE (unadjusted OR: 0.84, 95% CI: 0.49--1.45). Adjusted analyses showed that guideline concordance was not associated with ADEs (OR: 0.78, 95% CI: 0.25--2.46), and this relationship did not differ by dental setting (Wald χ² p-value for interaction = 0.601). Conclusion: Antibiotic-associated ADEs did not differ by setting or guideline concordance. [ABSTRACT FROM AUTHOR]

Sea spray aerosols (SSAs) represent one of the most abundant aerosol types on a global scale and have been observed at all altitudes including the upper troposphere. SSA has been explored in recent years as a source of ice-nucleating particles (INPs) in cirrus clouds due to the ubiquity of cirrus clouds and the uncertainties in their radiative forcing. This study expands upon previous works on low-temperature ice nucleation of SSA by investigating the effects of atmospheric aging of SSA and the ice-nucleating activity of newly formed secondary marine aerosols (SMAs) using an oxidation flow reactor. Polydisperse aerosol distributions were generated from a marine aerosol reference tank (MART) filled with 120 L of real or artificial seawater and were dried to very low relative humidity to crystallize the salt constituents of SSA prior to their subsequent freezing, which was measured using a continuous flow diffusion chamber (CFDC). Results show that for primary SSA (pSSA), as well as aged SSA and SMA (aSSA + SMA) at temperatures >220 K, homogeneous conditions (92 %–97 % relative humidity with respect to water – RH w) were required to freeze 1 % of the particles. However, below 220 K, heterogeneous nucleation occurs for both pSSA and aSSA + SMA at much lower RH w , where up to 1 % of the aerosol population freezes between 75 % and 80 % RH w. Similarities between freezing behaviors of the pSSA and aSSA + SMA at all temperatures suggest that the contributions of condensed organics onto the pSSA or alteration of functional groups in pSSA via atmospheric aging did not hinder the major heterogeneous ice nucleation process at these cirrus temperatures, which have previously been shown to be dominated by the crystalline salts. Occurrence of a 1 % frozen fraction of SMA, generated in the absence of primary SSA, was observed at or near water saturation below 220 K, suggesting it is not an effective INP at cirrus temperatures, similar to findings in the literature on other organic aerosols. Thus, any SMA coatings on the pSSA would only decrease the ice nucleation behavior of pSSA if the organic components were able to significantly delay water uptake of the inorganic salts, and apparently this was not the case. Results from this study demonstrate the ability of lofted primary sea spray particles to remain an effective ice nucleator at cirrus temperatures, even after atmospheric aging has occurred over a period of days in the marine boundary layer prior to lofting. We were not able to address aging processes under upper-tropospheric conditions. [ABSTRACT FROM AUTHOR]

Rapid Arctic climate warming, amplified relative to lower-latitude regions, has led to permafrost thaw and associated thermokarst processes. Recent work has shown permafrost is a rich source of ice-nucleating particles (INPs) that can initiate ice formation in supercooled liquid clouds. Since the phase of Arctic clouds strongly affects the surface energy budget, especially over ice-laden surfaces, characterizing INP sources in this region is critical. For the first time, we provide a large-scale survey of potential INP sources in tundra terrain where thermokarst processes are active and relate to INPs in the air. Permafrost, seasonally thawed active layer, ice wedge, vegetation, water, and aerosol samples were collected near Utqiaġvik, Alaska, in late summer and analyzed for their INP contents. Permafrost was confirmed as a rich source of INPs that was enhanced near the coast. Sensitivity to heating revealed differences in INPs from similar sources, such as the permafrost and active layer. Water, vegetation, and ice wedge INPs had the highest heat-labile percentage. The aerosol likely contained a mixture of known and unsurveyed INP types that were inferred as biological. Arctic water bodies were shown to be potential important links of sources to the atmosphere in thermokarst regions. Therefore, a positive relationship found with total organic carbon considering all water bodies gives a mechanism for future parameterization as permafrost continues to thaw and drive regional landscape shifts. [ABSTRACT FROM AUTHOR]