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1.
Head Neck ; 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32357277

RESUMO

The 2019 novel coronavirus disease (COVID-19) pandemic has been spreading worldwide at an alarming rate. Health-care workers have been confronted with the challenge of not only treating patients with the virus, but also managing the disruption of health-care services caused by COVID-19. In anticipation of outbreak, clinic sessions and operation theater lists have been actively cut back since February 2020 to reduce hospital admissions and clinic attendances. This has severely disrupted health-care services, leading to accumulating clinic caseload and substantial delays for operations. The head and neck cancer service has been faced with the difficult task of managing the balance between infection risk to health-care providers and the risk of disease progression from prolonged waiting times. We share our experience in Hong Kong on the mitigation of head and neck cancer service disruption through telehealth and multi-institution collaboration.

2.
Environ Sci Technol ; 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32428397

RESUMO

Relative humidity (RH) history that manifests the cycling of dehydration (water evaporation) and hydration (water uptake) may affect particle-phase reactions, products from which have strong influences on the physical properties and thus climatic effects of atmospheric particles. Using single-trapped particles, we show herein hygroscopic growths of mixed particles with reactive species undergoing three types of RH cycles, simulating different degrees of particle-phase reactions in the atmosphere. The reactive species are the widely known α-dicarbonyl, glyoxal (GLY), and five reduced nitrogenous species, including ammonium sulfate (AS), glycine (GC), L-alanine (AL), dimethylamine (DMA) and diethylamine (DEA). Results showed that the mixed particles after reactions generally had altered efflorescence relative humidity (ERH) and deliquescence relative humidity (DRH) values, and reduced hygroscopic growths at moderately high RH (>80%) conditions. For example, with an additional slow drying step, the mean mass growth factors at 90% RH during dehydration dropped from 2.56 to 2.02 for GC/GLY mixed particles and from 2.45 to 1.23 for AL/GLY mixed particles. The reduced hygroscopicity with more RH cycling will thus lead to less efficient light scattering of the mixed particles, thereby resulting in less cooling and exacerbating the direct heating due to the light absorption by the products formed.

3.
PLoS Comput Biol ; 16(4): e1007753, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32275708

RESUMO

Precision oncology has primarily relied on coding mutations as biomarkers of response to therapies. While transcriptome analysis can provide valuable information, incorporation into workflows has been difficult. For example, the relative rather than absolute gene expression level needs to be considered, requiring differential expression analysis across samples. However, expression programs related to the cell-of-origin and tumor microenvironment effects confound the search for cancer-specific expression changes. To address these challenges, we developed an unsupervised clustering approach for discovering differential pathway expression within cancer cohorts using gene expression measurements. The hydra approach uses a Dirichlet process mixture model to automatically detect multimodally distributed genes and expression signatures without the need for matched normal tissue. We demonstrate that the hydra approach is more sensitive than widely-used gene set enrichment approaches for detecting multimodal expression signatures. Application of the hydra analysis framework to small blue round cell tumors (including rhabdomyosarcoma, synovial sarcoma, neuroblastoma, Ewing sarcoma, and osteosarcoma) identified expression signatures associated with changes in the tumor microenvironment. The hydra approach also identified an association between ATRX deletions and elevated immune marker expression in high-risk neuroblastoma. Notably, hydra analysis of all small blue round cell tumors revealed similar subtypes, characterized by changes to infiltrating immune and stromal expression signatures.

4.
Chempluschem ; 85(4): 734-741, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32286741

RESUMO

Strontium titanate (SrTiO3 ) based materials are promising for high-temperature thermoelectric applications. In order to enhance their performance, annealing is usually required and carried out under various atmospheres. Annealing with graphite is quite effective, but the mechanism is not yet clear. In this work, we use IR spectroscopy and gas chromatography (GC) to monitor the chemical environment under the annealing conditions (1350 °C for 8 h under 16.9 mL/min N2 with graphite) and quantify the various gases evolved in the process. It is shown that reducing agents, H2 and CO (concentrations peaked at ca. 0.4-0.5 %), are generated from graphite in the annealing process. H2 is produced in carbon gasification reaction, which also generates CO. Additional CO is produced from incomplete combustion of carbon. In the annealing of a La-doped SrTiO3 -based ceramic with graphite, higher levels of H2 O and CO2 are detected, which is resulted from the reduction of the ceramic by H2 and CO, respectively. About 67 % of the oxygen vacancies were created by CO reduction while about 33 % by H2 reduction. The conclusions are well supported by direct weight loss measurements with a difference of less than 6 %.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32087023

RESUMO

OBJECTIVE: PsA patients who achieved sustained minimal disease activity (sMDA) had less subclinical atherosclerosis progression. The vascular effects of achieving other potential treatment targets, including the PsA Disease Activity Score (PASDAS) and the Disease Activity in PsA (DAPSA) score, remained uncertain. This study aimed to compare the vascular effects of achieving different treatment targets in PsA patients. METHOD: This is a post hoc analysis of a 2 year treat-to-target study aimed at MDA. A total of 101 consecutive PsA patients without overt cardiovascular disease were recruited. High-resolution carotid ultrasound and arterial stiffness markers were assessed annually. Low disease activity (LDA) was defined as MDA, DAPSA ≤14 or PASDAS ≤3.2. Sustained disease control was defined as achieving these targets at each visit from month 12 until month 24. RESULTS: Ninety patients [52 male (57.8%), age 50 years (s.d. 11)] who completed 24 months of follow-up were included in this analysis. A total of 44%, 48% and 45% of patients achieved sustained DAPSA LDA (sDAPDA-LDA), sustained PASDAS LDA (sPASDAS-LDA) and sMDA, respectively. Patients who achieved sMDA had significantly less progression of carotid intima-media thickness than those who did not (P = 0.031). Using multivariate analysis, achieving sMDA and sPASDAS-LDA had a protective effect on plaque progression, less increase in total plaque area, reduced mean intima-media thickness and reduced augmentation index after adjusting for covariates. In contrast, no significant differences in the progression of vascular parameters were demonstrated between patients who did or did not achieve sDAPSA-LDA. CONCLUSION: Achieving sMDA/sDASPAS-LDA, but not sDAPSA-LDA, was associated with a protective effect in subclinical atherosclerosis and arterial stiffness progression. A multidimensional domain of disease control might be better in minimizing cardiovascular risk in PsA.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32105137

RESUMO

There is some evidence that cannabis use is associated with lower cognitive performance and symptoms of attention-deficit/hyperactivity disorder (ADHD), but the existing literature is relatively inconsistent, potentially due to small samples in previous studies. Using a dimensional design, the current study examined cannabis use severity and age of first cannabis use in relation to neurocognitive performance and ADHD symptoms in a large sample of community adults (N = 1,008, Mage = 38.49, 56.0% female). Participants were assessed for cannabis involvement, neurocognitive performance, and ADHD symptoms. Dimensional relationships were investigated using multiple hierarchical regressions. Using a covariate model of age, income, sex, alcohol use, and tobacco use, severity of cannabis involvement was significantly associated with greater endorsement of both hyperactive-impulsive and inattentive ADHD symptoms but not with any other cognitive measures in the full sample. Exploratory analyses found greater cannabis use severity was associated with digit span forward and hyperactive ADHD symptoms in young adults (n = 371) and was associated with greater delay discounting, hyperactive, and impulsive ADHD symptoms in high-risk cannabis users (n = 161). Age of first cannabis use was not significantly associated with any neurocognitive variables or ADHD symptomatology in all analyses. The current findings provide evidence of a link between current cannabis misuse and both hyperactive and inattentive ADHD symptoms in general, and possible links to attention and impulsive delay discounting in subgroups of cannabis users, but no associations in other cognitive domains or implication of earlier initiation of cannabis use in relation to cognitive performance or ADHD. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

7.
JAMA Neurol ; 77(4): 517-521, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31904765

RESUMO

Importance: Biomarkers for chronic traumatic encephalopathy (CTE) are currently lacking. The radiotracer fluorine F 18-labeled (18F)-flortaucipir (FTP) detects tau pathology in Alzheimer disease, and positron emission tomography (PET) with FTP shows elevated binding in individuals at risk for CTE. No study, however, has assessed the correlation between in vivo FTP PET and postmortem tau in CTE. Objective: To assess the regional association between in vivo FTP binding and postmortem tau pathology in a patient with pathologically confirmed CTE. Design, Setting, and Participants: A white male former National Football League player with 17 years of US football exposure was clinically diagnosed with traumatic encephalopathy syndrome at a neurology tertiary referral center. 18F-Fludeoxyglucose, carbon 11-labeled Pittsburgh compound B, and FTP PET were performed 52 months prior to death, and magnetic resonance imaging, 50 months prior to death. Brain images were assessed qualitatively for abnormalities blinded to autopsy data. Autopsy was performed using a neurodegenerative research protocol. The FTP standardized uptake value ratios (inferior cerebellar gray reference region) and W-score (age-adjusted z-score) maps were compared with phosphorylated tau immunohistochemical analysis with monoclonal antibody CP13. Main Outcomes and Measures: Qualitative and quantitative comparisons between antemortem FTP PET and tau pathology at autopsy. Results: Flortaucipir uptake was distributed in a patchy, frontotemporal-predominant pattern that overlapped with regions showing neurodegeneration on magnetic resonance imaging and hypometabolism on 18F-fludeoxyglucose PET. Pathological assessment revealed stage 4 CTE; limbic argyrophilic grain disease; stage 2 limbic-predominant, age-related transactive response DNA-binding protein 43 encephalopathy; and Braak neurofibrillary tangle stage 3. 18F-Flortaucipir W-maps matched areas of high postmortem tau burden in left fusiform and inferior temporal gyri and juxtacortical frontal white matter. High FTP W-scores with low tau burden were found in the basal ganglia, thalamus, motor cortex, and calcarine cortex. No regions with low FTP W-scores corresponded to areas with high pathological tau burden. A modest correlation, which did not reach statistical significance (ρ = 0.35, P = .17), was found between FTP standardized uptake value ratio and tau area fraction at the regional level. Conclusions and Relevance: In this patient, FTP PET findings during life showed a modest correspondence with postmortem pathology in CTE. These findings suggest that FTP may have limited utility as a tau biomarker in CTE.

8.
EuroIntervention ; 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31985452

RESUMO

The commonly used left atrial appendage (LAA) occlusion (LAAO) devices, Watchman (Boston Scientific, Marlborough, MA, USA) and Amulet (Abbott, Plymouth, Minnesota, USA), both rely on oversizing for stabilization. Therefore, occluding large LAA (ostium >=31mm for Watchman or landing zone >=31mm for Amulet) are not possible. LAmbre (Lifetech Scientific Co., Shenzhen, China) device has an additional stabilization mechanism by catching the LAA trabeculations using its 8 claws1. This potentially allows LAmbre in occluding large LAA with ostium up to 40mm, i.e. size of its largest cover. The study aimed to evaluate procedural and short-term outcomes of LAmbre device in occluding large LAA.

10.
Neuroimage ; 208: 116425, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31805382

RESUMO

The human anterior insula (aINS) is a topographically organized brain region, in which ventral portions contribute to socio-emotional function through limbic and autonomic connections, whereas the dorsal aINS contributes to cognitive processes through frontal and parietal connections. Open questions remain, however, regarding how aINS connectivity varies over time. We implemented a novel approach combining seed-to-whole-brain sliding-window functional connectivity MRI and k-means clustering to assess time-varying functional connectivity of aINS subregions. We studied three independent large samples of healthy participants and longitudinal datasets to assess inter- and intra-subject stability, and related aINS time-varying functional connectivity profiles to dispositional empathy. We identified four robust aINS time-varying functional connectivity modes that displayed both "state" and "trait" characteristics: while modes featuring connectivity to sensory regions were modulated by eye closure, modes featuring connectivity to higher cognitive and emotional processing regions were stable over time and related to empathy measures.

11.
J Clin Invest ; 130(4): 1879-1895, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31874105

RESUMO

Few therapies are currently available for patients with KRAS-driven cancers, highlighting the need to identify new molecular targets that modulate central downstream effector pathways. Here we found that the microRNA (miRNA) cluster including miR181ab1 is a key modulator of KRAS-driven oncogenesis. Ablation of Mir181ab1 in genetically engineered mouse models of Kras-driven lung and pancreatic cancer was deleterious to tumor initiation and progression. Expression of both resident miRNAs in the Mir181ab1 cluster, miR181a1 and miR181b1, was necessary to rescue the Mir181ab1-loss phenotype, underscoring their nonredundant role. In human cancer cells, depletion of miR181ab1 impaired proliferation and 3D growth, whereas overexpression provided a proliferative advantage. Lastly, we unveiled miR181ab1-regulated genes responsible for this phenotype. These studies identified what we believe to be a previously unknown role for miR181ab1 as a potential therapeutic target in 2 highly aggressive and difficult to treat KRAS-mutated cancers.

12.
Ann Transl Med ; 7(20): 579, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31807560

RESUMO

Three-dimensional (3D) printing refers to the process by which physical objects are built by depositing materials in layers based on a specific digital design. It was initially used in manufacture industry. Inspired by the technology, clinicians have recently attempted to integrate 3D printing into medical applications. One of the medical specialties that has recently made such attempt is cardiology, especially in the field of structural heart disease (SHD). SHD refers to a group of non-coronary cardiovascular disorders and related interventions. Obvious examples are aortic stenosis, mitral regurgitation, atrial septal defect, and known or potential left atrial appendage (LAA) clots. In the last decade, cardiologists have witnessed a dramatic increase in the types and complexity of catheter-based interventions for SHD. Current imaging modalities have important limitations in accurate delineation of cardiac anatomies necessary for SHD interventions. Application of 3D printing in SHD interventional planning enables tangible appreciation of cardiac anatomy and allows in vitro interventional device testing. 3D printing is used in diagnostic workup, guidance of treatment strategies, and procedural simulation, facilitating hemodynamic research, enhancing interventional training, and promoting patient-clinician communication. In this review, we attempt to define the concept, technique, and work flow of 3D printing in SHD and its interventions, highlighting the reported clinical benefits and unsolved issues, as well as exploring future developments in this field.

13.
Neuron ; 104(5): 1000-1009.e7, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31668844

RESUMO

Manual dexterity requires proprioceptive feedback about the state of the hand. To date, study of the neural basis of proprioception in the cortex has focused primarily on reaching movements to the exclusion of hand-specific behaviors such as grasping. To fill this gap, we record both time-varying hand kinematics and neural activity evoked in somatosensory and motor cortices as monkeys grasp a variety of objects. We find that neurons in the somatosensory cortex, as well as in the motor cortex, preferentially track time-varying postures of multi-joint combinations spanning the entire hand. This contrasts with neural responses during reaching movements, which preferentially track time-varying movement kinematics of the arm, such as velocity and speed of the limb, rather than its time-varying postural configuration. These results suggest different representations of arm and hand movements suited to the different functional roles of these two effectors.

14.
Nat Med ; 25(11): 1783-1795, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31700175

RESUMO

Proinflammatory cytokines in the tumor microenvironment can promote tumor growth, yet their value as therapeutic targets remains underexploited. We validated the functional significance of the cardiotrophin-like cytokine factor 1 (CLCF1)-ciliary neurotrophic factor receptor (CNTFR) signaling axis in lung adenocarcinoma (LUAD) and generated a high-affinity soluble receptor (eCNTFR-Fc) that sequesters CLCF1, thereby inhibiting its oncogenic effects. eCNTFR-Fc inhibits tumor growth in multiple xenograft models and in an autochthonous, highly aggressive genetically engineered mouse model of LUAD, driven by activation of oncogenic Kras and loss of Trp53. Abrogation of CLCF1 through eCNTFR-Fc appears most effective in tumors driven by oncogenic KRAS. We observed a correlation between the effectiveness of eCNTFR-Fc and the presence of KRAS mutations that retain the intrinsic capacity to hydrolyze guanosine triphosphate, suggesting that the mechanism of action may be related to altered guanosine triphosphate loading. Overall, we nominate blockade of CLCF1-CNTFR signaling as a novel therapeutic opportunity for LUAD and potentially for other tumor types in which CLCF1 is present in the tumor microenvironment.


Assuntos
Adenocarcinoma de Pulmão/tratamento farmacológico , Proliferação de Células/genética , Subunidade alfa do Receptor do Fator Neutrófico Ciliar/genética , Citocinas/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Animais , Linhagem Celular Tumoral , Subunidade alfa do Receptor do Fator Neutrófico Ciliar/química , Citocinas/química , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucinas/genética , Camundongos , Mutação/genética , Ligação Proteica , Proteínas Proto-Oncogênicas p21(ras)/genética , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética , Ensaios Antitumorais Modelo de Xenoenxerto
15.
J Nucl Cardiol ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31768902

RESUMO

BACKGROUND: Rb-82 positron emission tomography (PET) myocardial perfusion imaging (MPI) is a robust tool for the evaluation of coronary artery disease (CAD). However, gastric uptake and spillover can be seen in 10% of Rb-82 PET MPI studies, commonly affecting the inferior wall, and can preclude the accurate identification of myocardial ischemia. We sought to understand the relationship between Rb-82 gastric uptake and the use of proton pump inhibitors (PPI). METHODS: 600 consecutive patients who presented for a clinically indicated Rb-82 PET MPI study were prospectively enrolled. In addition to the clinical history, PPI use was ascertained (medication, dose, frequency and duration of use, and time of last dose). Patients were categorized as PPI and non-PPI users. Rb-82 uptake in the gastrium, myocardium, and liver were measured at rest. Absolute uptake values and gastric:hepatic ratios were compared in PPI and non-PPI users. RESULT: Of 600 enrolled patients, 181 (30.2%) patients were using PPI. The gastric Rb-82 uptake in PPI users was 23% higher than non-PPI users (146 ± 52 kBq/cc vs 119 ± 40 kBq/cc, respectively; P < 0.001). The resting gastric:hepatic Rb-82 uptake ratio was also 23% higher in PPI vs non-PPI users (2.7 ± 1.0 vs 2.2 ± 0.8, respectively; P < 0.001). CONCLUSION: The gastric uptake of Rb-82 appears to be greater in patients actively using PPI and may identify a group who might be at greater risk of non-diagnostic Rb-82 PET MPI.

16.
Phys Rev Lett ; 123(11): 117201, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31573260

RESUMO

Through a combination of experimental measurements and theoretical modeling, we describe a strongly orbital-polarized insulating ground state in an (LaTiO_{3})_{2}/(LaCoO_{3})_{2} oxide heterostructure. X-ray absorption spectra and ab initio calculations show that an electron is transferred from the titanate to the cobaltate layers. The charge transfer, accompanied by a large octahedral distortion, induces a substantial orbital polarization in the cobaltate layer of a size unattainable via epitaxial strain alone. The asymmetry between in-plane and out-of-plane orbital occupancies in the high-spin cobaltate layer is predicted by theory and observed through x-ray linear dichroism experiments. Manipulating orbital configurations using interfacial coupling within heterostructures promises exciting ground-state engineering for realizing new emergent electronic phases in metal oxide superlattices.

18.
JAMA Netw Open ; 2(10): e1913968, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31651965

RESUMO

Importance: Pediatric cancers are epigenetic diseases; therefore, considering tumor gene expression information is necessary for a complete understanding of the tumorigenic processes. Objective: To evaluate the feasibility and utility of incorporating comparative gene expression information into the precision medicine framework for difficult-to-treat pediatric and young adult patients with cancer. Design, Setting, and Participants: This cohort study was conducted as a consortium between the University of California, Santa Cruz (UCSC) Treehouse Childhood Cancer Initiative and clinical genomic trials. RNA sequencing (RNA-Seq) data were obtained from the following 4 clinical sites and analyzed at UCSC: British Columbia Children's Hospital (n = 31), Lucile Packard Children's Hospital at Stanford University (n = 80), CHOC Children's Hospital and Hyundai Cancer Institute (n = 46), and the Pacific Pediatric Neuro-Oncology Consortium (n = 24). The study dates were January 1, 2016, to March 22, 2017. Exposures: Participants underwent tumor RNA-Seq profiling as part of 4 separate clinical trials at partner hospitals. The UCSC either downloaded RNA-Seq data from a partner institution for analysis in the cloud or provided a Docker pipeline that performed the same analysis at a partner institution. The UCSC then compared each participant's tumor RNA-Seq profile with more than 11 000 uniformly analyzed tumor profiles from pediatric and young adult patients with cancer, downloaded from public data repositories. These comparisons were used to identify genes and pathways that are significantly overexpressed in each patient's tumor. Results of the UCSC analysis were presented to clinical partners. Main Outcomes and Measures: Feasibility of a third-party institution (UCSC Treehouse Childhood Cancer Initiative) to obtain tumor RNA-Seq data from patients, conduct comparative analysis, and present analysis results to clinicians; and proportion of patients for whom comparative tumor gene expression analysis provided useful clinical and biological information. Results: Among 144 samples from children and young adults (median age at diagnosis, 9 years; range, 0-26 years; 72 of 118 [61.0%] male [26 patients sex unknown]) with a relapsed, refractory, or rare cancer treated on precision medicine protocols, RNA-Seq-derived gene expression was potentially useful for 99 of 144 samples (68.8%) compared with DNA mutation information that was potentially useful for only 34 of 74 samples (45.9%). Conclusions and Relevance: This study's findings suggest that tumor RNA-Seq comparisons may be feasible and highlight the potential clinical utility of incorporating such comparisons into the clinical genomic interpretation framework for difficult-to-treat pediatric and young adult patients with cancer. The study also highlights for the first time to date the potential clinical utility of harmonized publicly available genomic data sets.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31645344

RESUMO

Gliomatosis peritonei is a rare pathologic finding that is associated with ovarian teratomas and malignant mixed germ cell tumors. The occurrence of gliomatosis as a mature glial implant can impart an improved prognosis to patients with immature ovarian teratoma, making prompt and accurate diagnosis important. We describe a case of recurrent immature teratoma in a 10-yr-old female patient, in which comparative analysis of the RNA sequencing gene expression data from the patient's tumor was used effectively to aid in the diagnosis of gliomatosis peritonei.

20.
Proc Natl Acad Sci U S A ; 116(41): 20309-20314, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31548411

RESUMO

Four North Atlantic Aerosol and Marine Ecosystems Study (NAAMES) field campaigns from winter 2015 through spring 2018 sampled an extensive set of oceanographic and atmospheric parameters during the annual phytoplankton bloom cycle. This unique dataset provides four seasons of open-ocean observations of wind speed, sea surface temperature (SST), seawater particle attenuation at 660 nm (c p,660, a measure of ocean particulate organic carbon), bacterial production rates, and sea-spray aerosol size distributions and number concentrations (N SSA). The NAAMES measurements show moderate to strong correlations (0.56 < R < 0.70) between N SSA and local wind speeds in the marine boundary layer on hourly timescales, but this relationship weakens in the campaign averages that represent each season, in part because of the reduction in range of wind speed by multiday averaging. N SSA correlates weakly with seawater cp,660 (R = 0.36, P << 0.01), but the correlation with cp,660, is improved (R = 0.51, P < 0.05) for periods of low wind speeds. In addition, NAAMES measurements provide observational dependence of SSA mode diameter (d m) on SST, with d m increasing to larger sizes at higher SST (R = 0.60, P << 0.01) on hourly timescales. These results imply that climate models using bimodal SSA parameterizations to wind speed rather than a single SSA mode that varies with SST may overestimate SSA number concentrations (hence cloud condensation nuclei) by a factor of 4 to 7 and may underestimate SSA scattering (hence direct radiative effects) by a factor of 2 to 5, in addition to overpredicting variability in SSA scattering from wind speed by a factor of 5.

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