Pseudo-distances on symplectomorphism groups and applications to flux theory

Starting from a given norm on the vector space of exact 1-forms of a compact symplectic manifold, we produce pseudo-distances on its symplectomorphism group by generalizing an idea due to Banyaga. We prove that in some cases (which include Banyaga's construction), their restriction to the Hamiltonian diffeomorphism group is equivalent to the distance induced by the initial norm on exact 1-forms. We also define genuine "distances to the Hamiltonian diffeomorphism group" which we use to derive several consequences, mainly in terms of flux groups.Comment: 21 pages, no figure; v2. various typos corrected, some references added. Published in Mathematische Zeitschrif

Revisiting the disappearance of terrestrial dissolved organic matter in the ocean : a delta C-13 study

Organic carbon (OC) depleted in C-13 is a widely used tracer for terrestrial organic matter (OM) in aquatic systems. Photochemical reactions can, however, change delta C-13 of dissolved organic carbon (DOC) when chromophoric, aromatic-rich terrestrial OC is selectively mineralized. We assessed the robustness of the delta C-13 signature of DOC (delta C-13(DOC)) as a tracer for terrestrial OM by estimating its change during the photobleaching of chromophoric DOM (CDOM) from 10 large rivers. These rivers cumulatively account for approximately one-third of the world's freshwater discharge to the global ocean. Photobleaching of CDOM by simulated solar radiation was associated with the photochemical mineralization of 16 to 43% of the DOC and, by preferentially removing compounds depleted in C-13, caused a 1 to 2.9 parts per thousand enrichment in delta C-13 in the residual DOC. Such solar-radiation-induced photochemical isotopic shift could bias the calculations of terrestrial OM discharge in coastal oceans towards the marine end-member. Shifts in terrestrial delta C-13(DOC) should be taken into account when constraining the terrestrial end-member in global calculation of terrestrially derived DOM in the world ocean.Peer reviewe

Religious norms, norm conflict, and religious identification

The present research sought to understand how religious identification is associated with normative practices and with norm conflict (the perception that people within the religious group are not all enacting the same standards or rules for behaviour). Using a multi-faith sample (N=400) we replicate positive associations of religious identification with engaging in normative practices such as prayer, and the associations of both identification and normative practices with stronger well-being. Religious norm conflict was associated with lower identification and lower well-being, however. Three coping strategies were examined: 1) engaging in normative ritual practices was protective of identification and well-being; 2) affirming that the conflict occurs on less important (vs core) religious norms was associated with higher well-being, but not with identification; and 3) challenging the religious norm was associated with lower well-being, but did not alter religious identification

Exact Lagrangian submanifolds in simply-connected cotangent bundles

We consider exact Lagrangian submanifolds in cotangent bundles. Under certain additional restrictions (triviality of the fundamental group of the cotangent bundle, and of the Maslov class and second Stiefel-Whitney class of the Lagrangian submanifold) we prove such submanifolds are Floer-cohomologically indistinguishable from the zero-section. This implies strong restrictions on their topology. An essentially equivalent result was recently proved independently by Nadler, using a different approach.Comment: 28 pages, 3 figures. Version 2 -- derivation and discussion of the spectral sequence considerably expanded. Other minor change

Face Masks Impact Auditory and Audiovisual Consonant Recognition in Children With and Without Hearing Loss

Teachers and students are wearing face masks in many classrooms to limit the spread of the coronavirus. Face masks disrupt speech understanding by concealing lip-reading cues and reducing transmission of high-frequency acoustic speech content. Transparent masks provide greater access to visual speech cues than opaque masks but tend to cause greater acoustic attenuation. This study examined the effects of four types of face masks on auditory-only and audiovisual speech recognition in 18 children with bilateral hearing loss, 16 children with normal hearing, and 38 adults with normal hearing tested in their homes, as well as 15 adults with normal hearing tested in the laboratory. Stimuli simulated the acoustic attenuation and visual obstruction caused by four different face masks: hospital, fabric, and two transparent masks. Participants tested in their homes completed auditory-only and audiovisual consonant recognition tests with speech-spectrum noise at 0 dB SNR. Adults tested in the lab completed the same tests at 0 and/or −10 dB SNR. A subset of participants from each group completed a visual-only consonant recognition test with no mask. Consonant recognition accuracy and transmission of three phonetic features (place of articulation, manner of articulation, and voicing) were analyzed using linear mixed-effects models. Children with hearing loss identified consonants less accurately than children with normal hearing and adults with normal hearing tested at 0 dB SNR. However, all the groups were similarly impacted by face masks. Under auditory-only conditions, results were consistent with the pattern of high-frequency acoustic attenuation; hospital masks had the least impact on performance. Under audiovisual conditions, transparent masks had less impact on performance than opaque masks. High-frequency attenuation and visual obstruction had the greatest impact on place perception. The latter finding was consistent with the visual-only feature transmission data. These results suggest that the combination of noise and face masks negatively impacts speech understanding in children. The best mask for promoting speech understanding in noisy environments depend on whether visual cues will be accessible: hospital masks are best under auditory-only conditions, but well-fit transparent masks are best when listeners have a clear, consistent view of the talker’s face

Regulation of Motor Function and Behavior by Atypical Chemokine Receptor 1

The final publication is available at Springer via http://dx.doi.org/10.1007/s10519-014-9665-7Atypical Chemokine Receptor 1 (ACKR1), previously known as the Duffy Antigen Receptor for Chemokines, stands out among chemokine receptors for its high selective expression on Purkinje cells of the cerebellum, consistent with the ability of ACKR1 ligands to activate Purkinje cells in vitro. Nevertheless, evidence for ACKR1 regulation of brain function in vivo has been lacking. Here we demonstrate that Ackr1−/− mice have markedly impaired balance and ataxia when placed on a rotating rod and increased tremor when injected with harmaline, a drug that induces whole-body tremor by activating Purkinje cells. Ackr1−/− mice also exhibited impaired exploratory behavior, increased anxiety-like behavior and frequent episodes of marked hypoactivity under low-stress conditions. The behavioral phenotype of Ackr1−/− mice was the opposite of the phenotype occurring in mice with cerebellar degeneration and the defects persisted when Ackr1 was deficient only on non-hematopoietic cells. We conclude that normal motor function and behavior depend in part on negative regulation of Purkinje cell activity by Ackr1

Temporal Trends in the Use of Drug-eluting Stents for Approved and Off-label Indications: A Longitudinal Analysis of a Large Multicenter Percutaneous Coronary Intervention Registry

Background We sought to examine the temporal variations in the rate of both bare-metal stent (BMS) and drug-eluting stent (DES) use for off-label indications after the reports of an increased risk of very late stent thrombosis in patients with DES at the 2006 meeting of the European Society of Cardiology (ESC). Hypothesis To determine whether the decrease in use of DES has affected both on and off-label indications. Methods The study cohort included patients undergoing coronary intervention in a large regional registry, the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2). Patient demographic and clinical characteristics for patients with DES in the third quarter of 2006 (pre-ESC) were compared to those from the fourth quarter of 2008 (post-guideline changes). Use of DES for off-label indications, such as ST-segment elevation myocardial infarction (STEMI), in-stent restenosis (ISR), and saphenous vein graft (SVG) interventions, were evaluated. Results The overall deployment of DES fell sharply from 83% pre-ESC to a plateau of 58% in the first quarter of 2008. This corresponded to a rise in BMS use, while angioplasty procedures stayed the same. The STEMI subgroup showed the most dramatic change, from 78% to only 36%. Off-label use in SVGs showed a similar trend, from 74% to 43%. Drug-eluting stent deployment for ISR was less affected, though it also fell 25% (from 79%–56%). Conclusions The use of DES has fallen dramatically from June 2006 to December 2008, particularly for nonapproved indications. Our study provides a real-world assessment of contemporary change in DES use in response to the presentation of negative observational studies. Copyright © 2010 Wiley Periodicals, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65057/1/20717_ftp.pd

Incidence of the “Adrenaline Rush” and Vasovagal Response with Local Anesthetic Injection

Background: Many patients feel an “adrenaline rush” or a vasovagal reaction when injected with lidocaine and epinephrine during wide awake surgery. The incidence of these reactions is not well documented in the literature. Methods: In total, 387 patients were prospectively injected with lidocaine and epinephrine for minor procedures without sedation between July 1, 2019 and November 1, 2020. A concentration of epinephrine with 1:100,000 in 2% lidocaine was injected, with most patients getting less than 20 mL of volume. Results: Eight (2.2%) of the patients had adrenaline rush symptoms, which included nervousness, anxiety, tremors, shaky feelings, flushing, diaphoresis, light-headedness, tingling, and “heart racing.” Seven patients (1.8%) experienced vasovagal responses, which included nausea, a feeling of being unwell, faint, or lightheaded, or had circumoral pallor. Conclusions: Patients run a low risk of feeling an adrenaline rush or vasovagal reaction when injected with lidocaine and epinephrine. Routinely advising patients that the adrenaline rush can happen, and that this is not an allergic reaction can be helpful to allay fear of the unknown and to prevent false allergy beliefs. Injecting patients lying down may decrease the incidence of vasovagal reactions by increasing cerebral blood flow with the advantage of gravity

The future is now: Model-based clinical trial design for Alzheimer's disease

Failures in trials for Alzheimer's disease (AD) may be attributable to inadequate dosing, population selection, drug inefficacy, or insufficient design optimization. The Coalition Against Major Diseases (CAMD) was formed in 2008 to develop drug development tools (DDT) to expedite drug development for AD and Parkinson's disease.1 CAMD led a process that successfully advanced a clinical trial simulation (CTS) tool for AD through the formal regulatory review process at the US Food and Drug Administration (FDA) and European Medicines Agency (EMA)