bluuebunny/crossref_metadata_2025 huggingface dataset:
Microbiologic effect of two topical anti‐infective treatments on ligature‐induced peri‐implantitis: A pilot study in dogs
Authors: Ramos Umberto Demoner , Suaid Flavia , Wikesjö Ulf M.E. , Susin Cristiano , Vital Patrícia Conde , de Souza Sérgio Luis Scombatti , Messora Michel Reis , Palioto Daniela Bazan , Novaes Arthur Belém
Published: May 2018

Background

The aim of this split‐mouth design pilot study in dogs was to assess microbiologic effects of two topical anti‐infective treatment protocols on dental implants subjected to ligature‐induced peri‐implantitis, without use of systemic antibiotics.

Methods

Eight adult Beagle dogs each received four dental implants in contralateral, edentulated, mandibular jaw quadrants. After 8 weeks, silk ligatures were installed, to be removed after another 8 weeks. After 6 additional weeks, induced peri‐implantitis lesions were subjected to either antimicrobial photodynamic therapy (aPDT) or a topical tetracycline (TTC) hydrochloride (50 mg/mL) solution. Microbiologic samples were collected from the deepest proximal peri‐implantitis site in each jaw quadrant before and after treatment. The samples were analyzed using DNA‐DNA hybridization checkerboard technique.

Results

Peri‐implantitis induction successfully produced lesions with microbiologic characteristics similar to those found in humans. Overall results showed effective bacterial count reductions for both protocols. aPDT demonstrated major reductions of the red complex, but no statistical differences between groups were observed when adjusted for multiple comparisons.

Conclusion

aPDT and TTC successfully decontaminated infected implant surfaces. Implant decontamination with aPDT appears to be a viable alternative to TTC in the management of peri‐implantitis infection.
Revision thoracic slide tracheoplasty: Outcomes following unsuccessful tracheal reconstruction
Authors: Sidell Douglas R. , Hart Catherine K. , Tabangin Meredith E. , Bryant Roosevelt , Rutter Michael J. , Manning Peter B. , Meinzen‐Derr Jareen , Balakrishnan Karthik , Yang Christina , de Alarcon Alessandro
Published: May 2018

Objectives/Hypothesis

Over the past decade, thoracic slide tracheoplasty (TST) has become the principal operation in the management of congenital tracheal stenosis. The purpose of this report was to describe our experience with revision TST following unsuccessful prior tracheal reconstruction.

Study Design

Retrospective analysis at an academic children's hospital.

Methods

Patients undergoing TST on cardiopulmonary bypass between January 2005 and May 2014 were reviewed. Patients with a history of prior airway surgery were extracted for further analysis. Preoperative patient variables and postoperative outcomes were evaluated and compared between patients undergoing revision slide tracheoplasty (RTST) and a control group of 26 matched patients undergoing primary surgery TST.

Results

Twenty‐six revision patients (25 referrals, one primary patient) of 162 patients reviewed over the study period met inclusion criteria. Twenty‐three patients had a history of complete tracheal rings, and three patients had cartilaginous deficiency. A total of 41 airway reconstruction procedures had been performed prior to RTST. When compared to primary TST, patients undergoing RTST required fewer cardiac procedures intraoperatively, and fewer mean ventilator hours (P = .01) postoperatively. There was no significant difference in the median length of stay, requirement of >48 hours ventilation, or postoperative complications between groups. There was one nonsurgical postoperative mortality following RTST.

Conclusions

Despite some differences in the postoperative management when compared to nonrevision cases, revision TST can be successfully performed after prior tracheal reconstruction with good postoperative outcomes.

Level of Evidence

4. Laryngoscope, 128:2181–2186, 2018
Contemporary analysis of practicing otolaryngologists
Authors: Harrill Willard C. , Melon David E. , Seshul Merritt J. , Katz Marc S. , Zanation Adam M.
Published: May 2018

Objectives/Hypothesis

To investigate contemporary issues facing practicing otolaryngologists including workforce dynamics, ancillary service modeling, otolaryngic allergy integration, ambulatory surgery center utilization, and relevant certificate of need legislation.

Study Design

A cross‐sectional survey analysis of academic and private practicing otolaryngologists in North and South Carolina in 2016.

Methods

A cross‐sectional survey was e‐mailed to 510 practicing otolaryngologists in North and South Carolina.

Results

A 21.3% survey response rate was achieved. Otolaryngology workforce was defined by horizontal aggregation of otolaryngologists into larger group models, with fewer solo practitioners being replaced by younger otolaryngologists or employing otolaryngology extenders. Excluding academic practice, few otolaryngologists have chosen direct hospital employment as a career option, although otolaryngologists with fewer years of practice are pursuing that option with greater frequency. Ancillary services showed audiology and hearing aid services being the most common, followed by otolaryngic allergy, point‐of‐service computed tomography, and ultrasound. Although otolaryngologists tend to avoid vertical integration, ambulatory surgery center (ASC) ownership trends favor a joint venture model with a hospital system partner. Most otolaryngologists favor changes to certificate of need legislation to improve patient access to these lower‐cost facilities, regardless of whether they currently utilize or have access to an ASC.

Conclusions

Otolaryngology is uniquely positioned to adapt and respond to current paradigm shifts within ambulatory medicine. Further analysis is needed to prepare current and future otolaryngologists for the demands and opportunities these challenges pose as patient‐centered care models and consumer dynamics shape future patient expectations and utilization of healthcare.

Level of Evidence

5. Laryngoscope, 2490–2499, 2018
Revision cochlear implant surgery in children: Surgical and audiological outcomes
Authors: Yeung Jeffrey , Griffin Amanda , Newton Stephen , Kenna Margaret , Licameli Greg R.
Published: May 2018

Objectives/Hypothesis

To determine the incidence of cochlear implant failure and to examine surgical and audiological outcomes.

Study Design

Retrospective review, case series.

Methods

This study sought indications for revision surgery, surgical findings, and outcomes, and audiological outcomes in pediatric cochlear implant patients. Pre‐ and postcochlear reimplantation word recognition performance was analyzed using a modified version of the Pediatric Ranked Order Speech Perception (PROSPER) score.

Results

Over a 20‐year period, a total of 868 cochlear implants were performed in 578 patients. The overall institutional reimplant rate was 5.9%. The indications for explantation were hard failure (30), soft failure (23), and medical/surgical indication (13). A significant portion of devices belonged to vendor recalled batches (15) or were damaged by head trauma (eight). Full electrode insertion was achieved in all 62 reimplantations. Post‐reimplantation Boston Children's Hospital modified PROSER scores were either stable or improved compared to pre‐reimplantation scores.

Conclusions

The need for cochlear implant revision/reimplantation is infrequent, but the rate is not inconsequential. Hard and soft device failures account for the majority of reimplants. Surgical complications during reimplantation is low, and post‐reimplantation audiological performance is excellent.

Level of Evidence

4. Laryngoscope, 2619–2624, 2018
Risk factors of cancer occurrence after surgery of oral intraepithelial neoplasia: A long‐term retrospective study
Authors: Ballivet de Régloix Stanislas , Badois Nathalie , Bernardeschi Celine , Jouffroy Thomas , Hofmann Caroline
Published: May 2018

Objective

Oral intraepithelial neoplasia (OIN) is a premalignant lesion of oral mucosa graded I through III according to the importance of atypic cells and the thickness of the dysplastic layers. The aim of this study was to evaluate the long‐term clinical course of OIN lesions and identify predictive factors of outcomes.

Methods

The clinical, surgical, and follow‐up data of the patients consecutively treated for OIN by primary surgical removal in a referral anti‐cancer center from November 1998 to March 2009 were retrospectively analyzed. The main outcome parameters were the 10‐year disease‐free survival (DFS), cancer‐free survival (CFS), overall survival (OS), and disease‐specific survival (DSS) rates (Kaplan‐Meier).

Results

Thirty‐one patients were included. Patients with positive or close margins (n = 15) had a significantly lower 10‐year CFS rate (46.7% vs. 92.38%; P = .004) than patients with negative margins. This predictive factor remained significant in multivariate analysis (hazard ratio, 9.157; 95% confidence interval, 1.4–60.6). There was no significant difference in the 10‐year DFS (33.3% vs. 48.7%; P = .2), DSS (92.8% vs. 100%; P = .1), and OS (92.8% vs. 69.6%; P = .2) rates between these two groups. Neither the initial OIN grade nor other clinical or surgical parameters were found to be significant predictors of outcomes.

Conclusion

In this long‐term follow‐up study on histologically proven OIN treated by primary surgery, positive or close margins status was the only independent predictive factor of progression to cancer. Therefore, we warmly recommand performing re‐resection rather than surveillance in cases with positive margins. Oral intraepithelial neoplasia grading or lesion size were not significant predictors of outcomes.

Level of Evidence

4. Laryngoscope, 2546–2551, 2018
Vegetation transitions drive the autotrophy–heterotrophy balance in Arctic lakes
Authors: McGowan Suzanne , Anderson N. John , Edwards Mary E. , Hopla Emma , Jones Viv , Langdon Pete G. , Law Antonia , Solovieva Nadia , Turner Simon , van Hardenbroek Maarten , Whiteford Erika J , Wiik Emma
Published: May 2018

“Arctic greening” will alter vegetation quantity and quality in northern watersheds, with possible consequences for lake metabolic balance. We used paleolimnology from six Arctic lakes in Greenland, Norway, and Alaska to develop a conceptual model describing how climate‐driven shifts in terrestrial vegetation (spanning herb to boreal forest) influence lake autotrophic biomass (as chlorophyll and carotenoid pigments). Major autotrophic transitions occurred, including (1) optimal production of siliceous algae and cyanobacteria/chlorophytes at intermediate vegetation cover (dwarf shrub and Betula; dissolved organic carbon (DOC) range of 2–4 mg L−1), below and above which UVR exposure (DOC; < 2 mgL−1) and light extinction (DOC; > 4 mgL−1), respectively limit algal biomass, (2) an increase in potentially mixotrophic cryptophytes with higher forest cover and allochthonous carbon supply. Vegetation cover appears to influence lake autotrophs by changing influx of (colored) dissolved organic matter which has multiple interacting roles—as a photoprotectant—in light attenuation and in macronutrient (carbon, nitrogen) supply.
The limits of Riemann solutions to the simplified pressureless Euler system with flux approximation
Authors: Sun Meina
Published: May 2018

The formation of vacuum state and delta shock wave in the solutions to the Riemann problem for the simplified pressureless Euler system is considered under the linear approximations of flux functions. The method is to perturb the non‐strictly hyperbolic system into a nearby strictly hyperbolic system by introducing appropriately the linear approximations of flux functions. The solutions to the Riemann problem for the approximated system can be constructed explicitly and then the formation of vacuum state and delta shock wave can be observed by taking the perturbation parameter tend to zero in the solutions.
Measuring plot scale woodland structure using terrestrial laser scanning
Authors: Muir Jasmine , Phinn Stuart , Eyre Teresa , Scarth Peter
Published: May 2018

Terrestrial laser scanning (TLS) can be used to characterize a woodland site by measuring structural attributes of the vegetation community. In Australia, government funded programs monitor vegetation structure using manual field surveys to assess change and ecological condition. In this study, we examined whether structural attributes commonly assessed in woodland ecology surveys can be extracted from a single TLS scan. Attributes of the ground, shrub and overstory vegetation layers were evaluated at nine open woodland sites in central Western Queensland. We used 0.1 m voxels to aggregate returns. Our results show that, compared with field assessment by highly experienced ecologists, TLS can rapidly characterize structural attributes for tree canopy cover, maximum tree height, average tree height (R2 > 0.9) and average diameter at breast height (R2 = 0.77). However, we could not accurately determine shrub height, shrub canopy cover, shrub average height, ground cover (grass, litter and coarse woody debris) or the number of trees per hectare (R2 < 0.45). By analysing local minima in the histogram of the maximum height, we determined height thresholds for canopy strata, and applied these to determine the canopy layer with the most biomass – the ecologically dominant layer (EDL). While these results are promising for overstory assessment and defining canopy strata heights using TLS, they suggest that future research should focus on investigating improved classification methods to separate laser returns into shrub and tree objects for structural assessment at the plot scale.
Anion‐Regulated Hydroxysulfide Monoliths as OER/ORR/HER Electrocatalysts and their Applications in Self‐Powered Electrochemical Water Splitting
Authors: Wang Bin , Tang Cheng , Wang Hao‐Fan , Li Bo‐Quan , Cui Xiaoyang , Zhang Qiang
Published: May 2018

Trifunctional electrocatalysis for the oxygen evolution reaction, oxygen reduction reaction, and hydrogen evolution reaction constitutes the bottleneck of various sustainable energy devices and systems including rechargeable metal–air batteries and overall water splitting. Emerging macroscopically nanostructured catalysts are strongly requested for superior electrocatalytic activities and practical applications. Here, a 3D hydroxysulfide monolith with anion‐regulated NiFe hydroxysulfide nanosheets is rationally proposed. With abundant active sites and unique structure, the as‐obtained hydroxysulfide monolith exhibits superior electrocatalytic performance in oxygen evolution, hydrogen evolution, and oxygen reduction in alkaline electrolyte. When directly serving as electrodes, a small charge/discharge voltage gap of 0.76 V at 2.0 mA cm−2 and a high peak power density of 248 mW cm−2 are achieved for the liquid Zn−air batteries, and a low cell voltage of 1.62 V at 10 mA cm−2 is detected for water splitting units. When two Zn−air batteries are serially connected to power the water splitting unit, bulky O2 and H2 bubbles are continuously generated on both the composite electrodes. This work demonstrates an effective strategy for controllable anion regulation and rational design of the 3D self‐supporting hydroxysulfides, which is also enlightening for other advanced energy materials and diverse applications.
Simplified path integral for supersymmetric quantum mechanics and type-A trace anomalies
Authors: Bastianelli Fiorenzo , Corradini Olindo , Iacconi Laura
Published: May 2018

Abstract

Particles in a curved space are classically described by a nonlinear sigma model action that can be quantized through path integrals. The latter require a precise regularization to deal with the derivative interactions arising from the nonlinear kinetic term. Recently, for maximally symmetric spaces, simplified path integrals have been developed: they allow to trade the nonlinear kinetic term with a purely quadratic kinetic term (linear sigma model). This happens at the expense of introducing a suitable effective scalar potential, which contains the information on the curvature of the space. The simplified path integral provides a sensible gain in the efficiency of perturbative calculations. Here we extend the construction to models with N = 1 supersymmetry on the worldline, which are applicable to the first quantized description of a Dirac fermion. As an application we use the simplified worldline path integral to compute the type-A trace anomaly of a Dirac fermion in d dimensions up to d = 16.
Inclusive prompt photon production in electron-nucleus scattering at small x
Authors: Roy Kaushik , Venugopalan Raju
Published: May 2018

Abstract

We compute the differential cross-section for inclusive prompt photon production in deeply inelastic scattering (DIS) of electrons on nuclei at smallxin the framework of the Color Glass Condensate (CGC) effective theory. The leading order (LO) computation in this framework resums leading logarithms inxas well as power corrections to all orders inQs,A2/Q2, whereQs,A(x) is the nuclear saturation scale. This LO result is proportional to universal dipole and quadrupole Wilson line correlators in the nucleus. In the soft photon limit, the Low-Burnett-Kroll theorem allows us to recover existing results on inclusive DIS dijet production. Thek⊥and collinearly factorized expressions for prompt photon production in DIS are also recovered in a leading twist approximation to our result. In the latter case, our result corresponds to the dominant next-to-leading order (NLO) perturbative QCD contribution at smallx. We next discuss the computation of the NLO corrections to inclusive prompt photon production in the CGC framework. In particular, we emphasize the advantages for higher order computations in inclusive photon production, and for fully inclusive DIS, arising from the simple momentum space structure of the dressed quark and gluon “shock wave” propagators in the “wrong” light cone gaugeA−= 0 for a nucleus moving withPN+ → ∞.
Renormalization-group equations of neutrino masses and flavor mixing parameters in matter
Authors: Xing Zhi-zhong , Zhou Shun , Zhou Ye-Ling
Published: May 2018

Abstract

We borrow the general idea of renormalization-group equations (RGEs) to understand how neutrino masses and flavor mixing parameters evolve when neutrinos propagate in a medium, highlighting a meaningful possibility that the genuine flavor quantities in vacuum can be extrapolated from their matter-corrected counterparts to be measured in some realistic neutrino oscillation experiments. Taking the matter parameter

$$ a\equiv 2\sqrt{2}\kern0.5em {G}_{\mathrm{F}}{N}_eE $$

a
≡
2

2

G
F

N
e

E

to be an arbitrary scale-like variable with N

e
being the net electron number density and E being the neutrino beam energy, we derive a complete set of differential equations for the effective neutrino mixing matrix V and the effective neutrino masses

$$ {\tilde{m}}_i $$

m
˜

i

(for i = 1, 2, 3). Given the standard parametrization of V , the RGEs for

$$ \left\{{\tilde{\theta}}_{12},\kern0.5em {\tilde{\theta}}_{13},\kern0.5em {\tilde{\theta}}_{23},\kern0.5em \tilde{\delta}\right\} $$

θ
˜

12

,

θ
˜

13

,

θ
˜

23

,

δ
˜

in matter are formulated for the first time. We demonstrate some useful differential invariants which retain the same form from vacuum to matter, including the well-known Naumov and Toshev relations. The RGEs of the partial μ-τ asymmetries, the off-diagonal asymmetries and the sides of unitarity triangles of V are also obtained as a by-product.
Zooming in on AdS3/CFT2 near a BPS bound
Authors: Hartong Jelle , Lei Yang , Obers Niels , Oling Gerben
Published: May 2018

Abstract

Any (d + 1)-dimensional CFT with a U(1) flavor symmetry, a BPS bound and an exactly marginal coupling admits a decoupling limit in which one zooms in on the spectrum close to the bound. This limit is an Inönü-Wigner contraction of so(2, d+1)⊕u(1) that leads to a relativistic algebra with a scaling generator but no conformal generators. In 2D CFTs, Lorentz boosts are abelian and by adding a second u(1) we find a contraction of two copies of sl(2, ℝ) ⊕ u(1) to two copies of P
2

c

, the 2-dimensional centrally extended Poincaré algebra. We show that the bulk is described by a novel non-Lorentzian geometry that we refer to as pseudo-Newton-Cartan geometry. Both the Chern-Simons action on sl(2, ℝ) ⊕ u(1) and the entire phase space of asymptotically AdS3 spacetimes are well-behaved in the corresponding limit if we fix the radial component for the u(1) connection. With this choice, the resulting Newton-Cartan foliation structure is now associated not with time, but with the emerging holographic direction. Since the leaves of this foliation do not mix, the emergence of the holographic direction is much simpler than in AdS3 holography. Furthermore, we show that the asymptotic symmetry algebra of the limit theory consists of a left- and a right-moving warped Virasoro algebra.
Affordable Laparoscopic Camera System (ALCS) Designed for Low‐ and Middle‐Income Countries: A Feasibility Study
Authors: Gheza Federico , Oginni Fadekemi O. , Crivellaro Simone , Masrur Mario A. , Adisa Adewale O.
Published: May 2018

Background

Minimally invasive surgical techniques (MISTs) could have tremendous benefits in resource‐poor environment. There is growing interest in MISTs in most low‐ and middle‐income countries (LMIC), but its adoption has remained limited; this is largely due to high cost of the initial setup, lack of technological backup and limited access to training among others. An affordable laparoscopic setup will go a long way in improving access to MISTs.

Methods

A common zero degrees 10 mm scope is attached on the camera of a low‐price smartphone. Two elastic bands are used to fix the scope right in front of the smartphone’s main camera; alternatively, a low‐cost camera coupler can be used. The device is covered with sterile transparent drapes and a light source connected with a fiber‐optic cable for endoscopic use. The image can be seen in real time on a common TV screen through an HDMI connection to the smartphone, with a sterile drape.

Results

We were able to perform the five tasks of the Fundamentals of Laparoscopic Surgery curriculum, using our vision system with proficiency. In a pig model, we performed a tubal ligation to simulate an appendectomy and we were able to suture. No major differences were measured between the two connection systems.

Conclusions

A low‐cost laparoscopic camera system can benefit surgeons and trainees in LMICs. The system is already attractive for use during training, but further studies are needed to evaluate its potential clinical role in LMICs.
Conditioned taste aversions
Authors: Chambers Kathleen C.
Published: May 2018

When one becomes ill after consuming a meal, there is a propensity to target a particular taste as the cause of the illness. The qualities of the taste most likely targeted include more novel, less preferred, and higher protein content. This association between a particular taste and illness is a form of learning that is termed conditioned taste aversion (CTA). A consequence of the learned association is that the taste will become aversive. When experiencing the taste again, individuals will show aversive reactions such as expressions of loathing, will experience mimicked illness sensations such as nausea, and subsequently, will avoid further exposure to the taste. The ability to acquire CTA occurs across species and across ages within a species. In the rat animal model, however, age differences exist in the capability of acquiring CTAs when increasingly longer intervals are imposed between consumption of a novel sweet solution and onset of illness. Pups have a decreased ability compared to young adults while aged rats have an increased ability. Evidence suggests that the failure of pups to acquire CTA at longer intervals is due to an immature retrieval mechanism and the facilitated ability of aged rats is due to a compromised clock mechanism that tracks the passage of time. Learned taste‐illness association serves the critical function of informing individuals of the toxic nature of certain foods, thus preventing further illness and potentially death. Additionally, it contributes to the hypophagia observed during cancer chemotherapy and may contribute to the hypophagia found while suffering from bacterial infection, chronic medical conditions such as cancer, and restrictive food intake disorders such as anorexia nervosa.
Analysis and modelling of unsteady shock train motions
Authors: Xiong Bing , Fan Xiao-qiang , Wang Zhen-guo , Tao Yuan
Published: May 2018

The characteristics and mechanism for unsteady shock train motions were experimentally studied in a constant-area rectangular duct. High-speed Schlieren techniques and high-frequency pressure measurements were utilized in this research. The results show that the shock train undergoes periodical motions in response to downstream periodical excitations. The mechanism for unsteady shock train motions is that the shock train keeps changing its moving speed to change the relative Mach number ahead of shock train to match the varying back-pressure condition. It can be found that the unsteady shock train motion can be predicted well with a theoretical model, which is based on this mechanism. A correlation between the amplitude of shock train motions and some flow parameters was illustrated using an analytical equation, which was confirmed by the experimental results.
Triassic chlorites from the Jura and the Catalan coastal range
Authors: Vivaldi J. L. Martin , MacEwan Douglas M. C.
Published: May 2018

The mineralogical nature of clays from the Catalan coastal range corresponding to Bunter, Muschelkalk and Keuper in stratigraphic sequence has been investigated. The predominant minerals present are illite, quartz, carbonate (calcium and/or magnesium) and chlorite in the Keuper and Muschelkalk and in the Bunter kaolinite is found in addition. Attention is drawn to the occurrence of interstratified chlorite and swelling chlorite, which association may be typical of clays deposited during Triassic time.
Adaptive multiscale predictive modelling
Authors: Oden J. Tinsley
Published: May 2018

The use of computational models and simulations to predict events that take place in our physical universe, or to predict the behaviour of engineered systems, has significantly advanced the pace of scientific discovery and the creation of new technologies for the benefit of humankind over recent decades, at least up to a point. That ‘point’ in recent history occurred around the time that the scientific community began to realize that true predictive science must deal with many formidable obstacles, including the determination of the reliability of the models in the presence of many uncertainties. To develop meaningful predictions one needs relevant data, itself possessing uncertainty due to experimental noise; in addition, one must determine model parameters, and concomitantly, there is the overriding need to select and validate models given the data and the goals of the simulation.

This article provides a broad overview of predictive computational science within the framework of what is often called the science of uncertainty quantification. The exposition is divided into three major parts. In Part 1, philosophical and statistical foundations of predictive science are developed within a Bayesian framework. There the case is made that the Bayesian framework provides, perhaps, a unique setting for handling all of the uncertainties encountered in scientific prediction. In Part 2, general frameworks and procedures for the calculation and validation of mathematical models of physical realities are given, all in a Bayesian setting. But beyond Bayes, an introduction to information theory, the maximum entropy principle, model sensitivity analysis and sampling methods such as MCMC are presented. In Part 3, the central problem of predictive computational science is addressed: the selection, adaptive control and validation of mathematical and computational models of complex systems. The Occam Plausibility Algorithm, OPAL, is introduced as a framework for model selection, calibration and validation. Applications to complex models of tumour growth are discussed.
Attentional Bias Modification for Social Anxiety Disorder: What do Patients Think and Why does it Matter?
Authors: Kuckertz Jennie M. , Schofield Casey A. , Clerkin Elise M. , Primack Jennifer , Boettcher Hannah , Weisberg Risa B. , Amir Nader , Beard Courtney
Published: May 2018

Background: In the past decade, a great deal of research has examined the efficacy and mechanisms of attentional bias modification (ABM), a computerized cognitive training intervention for anxiety and other disorders. However, little research has examined how anxious patients perceive ABM, and it is unclear to what extent perceptions of ABM influence outcome. Aims: To examine patient perceptions of ABM across two studies, using a mixed methods approach. Method: In the first study, participants completed a traditional ABM program and received a hand-out with minimal information about the purpose of the task. In the second study, participants completed an adaptive ABM program and were provided with more extensive rationale and instructions for changing attentional biases. Results: A number of themes emerged from qualitative data related to perceived symptom changes and mechanisms of action, acceptability, early perceptions of the program, barriers/facilitators to engagement, and responses to adaptive features. Moreover, quantitative data suggested that patients’ perceptions of the program predicted symptom reduction as well as change in attentional bias. Conclusions: Our quantitative data suggest that it may be possible to quickly and inexpensively identify some patients who may benefit from current ABM programs, although our qualitative data suggest that ABM needs major modifications before it will be an acceptable and credible treatment more broadly. Although the current study was limited by sample size and design features of the parent trials from which these data originated, our findings may be useful for guiding hypotheses in future studies examining patient perceptions towards ABM.
Confocal Laser Microscopy on Biofilms: Successes and Limitations
Authors: Pitts Betsey , Stewart Philip
Published: May 2018

Biofilms are communities of microbial cells and extracellular polymeric substances (EPS) attached to a surface. Bacteria exist preferentially in the biofilm state in nature and in many engineered systems. In this state, microbes tolerate antibiotics and disinfectants. Bacterial biofilms are now implicated in a wide range of human diseases and infections including cystic fibrosis, otitis media, chronic wounds, artificial joint and prosthesis infection, and many nosocomial infections. Biofilm-related infections and industrial fouling problems cost billions of dollars each year.
Freezing Techniques: History, Comparisons, and Applications
Authors: Graham Bill , Austin Jotham R , Kaech Andres , Heuser John E
Published: May 2018

Specimen preparation techniques have evolved hand in hand with microscopy since the first microscopes. Since the introduction of the first Electron Microscope (EM) in the 1930’s, the basic problem with biological electron microscopy has been to preserve the structure of soft condensed, hydrated matter (e.g. tissues, cells, proteins, etc.) so that they can be viewed in the harsh environment of the electron microscope's high vacuum and ionizing radiation. For this, cells must be “fixed” with chemical cross-linkers, commonly glutaraldehyde, formaldehyde or some combination of both, stained with heavy metals (osmium tetroxide that provides contrast of biological components), dehydrated with an organic solvent, and infiltrated with a resin for eventual thin-sectioning. Only then can it be viewed with the EM. Such treatment with chemical fixatives and stains remains the standard approaches to arrest biological processes in cells or tissues, but at the cost of introducing clearly recognizable artifacts.
Evaluation of Verticutting and Herbicides for Tropical Signalgrass (Urochloa subquadripara) Control in Turf
Authors: Pearsaul David G. , Leon Ramon G. , Sellers Brent A. , Silveira Maria L. , Odero D. Calvin
Published: May 2018

Tropical signalgrass (TSG) is one of the most problematic weeds found on golf courses, sports fields, and sod farms in south Florida. The recent ban of monosodium methane-arsonate (MSMA), an organic arsenical herbicide, from urban areas in Florida has left turfgrass managers searching for effective management options. In an effort to avoid relying solely on POST chemical control, this research examined the effect of combining a cultural practice, verticutting, along with PRE and POST herbicides as an integrated weed management approach to controlling TSG in hybrid bermudagrass. Field experiments were conducted at multiple locations over 2 yr in south Florida to: (1) determine whether verticutting before herbicide applications increases TSG control and (2) identify herbicide programs that effectively control TSG. No interactions between verticutting and herbicide programs were detected, but verticutting consistently provided a slight reduction (8% averaged across herbicide treatments) in TSG cover. Treatments containing a PRE herbicide resulted in a significant reduction (20% to 50%) in TSG cover at 52 wk after initial treatment (WAIT), while some POST herbicide treatments reduced TSG cover to <20% at 52 WAIT. A study was conducted to determine which POST herbicide combinations were most efficacious in controlling TSG. Amicarbazone alone provided ≤35% TSG control at 8 and 12 WAIT, but synergistic responses were observed between amicarbazone and mesotrione, trifloxysulfuron, and thiencarbazone+foramsulfuron+halosulfuron. Two- and three-way combinations of amicarbazone with these POST herbicides resulted in >80% TSG control at 4, 8, and 12 WAIT, with some reaching 100% TSG control at 4 WAIT. Based on these data, verticutting may provide limited complementary control, but certain combinations of POST herbicides exhibited excellent (>95%) TSG control.
Midcrustal Deformation in the Central Andes Constrained by Radial Anisotropy
Authors: Lynner Colton , Beck Susan L. , Zandt George , Porritt Robert W. , Lin Fan‐Chi , Eilon Zachary C.
Published: May 2018

The Central Andes are characterized by one of the largest orogenic plateaus worldwide. As a result, they are home to some of the thickest continental crust observed today (up to ~75‐km thick). Understanding the response of the crust to such overthickening provides insights into the ductile behavior of the midcrust and lower crust. One of the best tools for examining crustal‐scale features is ambient noise tomography, which takes advantage of the ambient noise wavefield to sample crustal depths in great detail. We extract Love and Rayleigh wave phase velocities from ambient noise data to invert for Vsh, Vsv, and radial anisotropy throughout the Central Andes. We capture detailed crustal structure, including pronounced along‐strike isotropic velocity heterogeneity and substantial (up to 10%) radial anisotropy that varies with depth. This crustal anisotropy may have several origins, but throughout the majority of the Central Andes, particularly beneath the Altiplano, we interpret radial anisotropy as the result of mineral alignment due to ductile crustal deformation. Only in the strongly volcanic Altiplano‐Puna Volcanic Complex is radial anisotropy likely caused by magmatic intrusions.
Production of High‐Sr Andesite and Dacite Magmas by Melting of Subducting Oceanic Lithosphere at Propagating Slab Tears
Authors: Pineda‐Velasco I. , Kitagawa H. , Nguyen T. ‐T. , Kobayashi K. , Nakamura E.
Published: May 2018

We present K‐Ar ages, major and trace element concentrations, and Sr‐Nd‐Pb isotope data for late Cenozoic volcanic rocks from the Chugoku district, southwest Japan arc. Andesite and dacite lavas in this region are enriched in Sr (mostly >800 μg g−1) and show geochemical characteristics of volcanic rocks commonly referred to as “adakite.” K‐Ar dating of these lavas revealed that the eruption of high‐Sr andesitic to dacitic magmas occurred during the last 2 Myr, following or concurrent with the eruption of basalt in adjacent regions. Trace‐element characteristics of high‐Sr andesites and dacites are consistent with the formation of their parent magmas by partial melting of the basaltic layer of the subducting Shikoku Basin Plate. Mass balance modeling of trace element concentrations and isotopic compositions suggests that the parental magmas of high‐Sr andesites and dacites are best explained by mixing of partial melts from oceanic crust (F = 5–15%) and sediment (F = 30%) at 80:20 to 55:45 ratios. Spatial coincidence of the occurrences of high‐Sr andesites and dacites and seismic gaps of the subducting slab demonstrates the causal link between slab melting and mantle upwelling at slab tears. We speculate that these tears could have been formed by subduction of ridges on the plate. A warm mantle upwelled through tears, preventing the solidification of the siliceous slab melts in the mantle and facilitating the transportation of these melts to the surface.
Deformation of Fine‐Grained Quartz Aggregates by Mixed Diffusion and Dislocation Creep
Authors: Fukuda Jun‐ichi , Holyoke Caleb W. , Kronenberg Andreas K.
Published: May 2018

Hot‐pressed polycrystalline quartz samples with grain sizes of 1.7–12.0 μm and water contents of 3,500 ppm H/Si were deformed in a solid‐pressure‐medium (Griggs‐type) deformation apparatus at temperatures of 600 to 950°C, confining pressures of 0.9 to 1.5 GPa and strain rates of 10−3.3 to 10−5.9/s. Two different flow regimes are distinguished at low and high temperatures. The stress exponent determined at low temperatures (600–750°C) increased from 2.9 to 5.2 with an activation energy of 129 ± 33 kJ/mol, consistent with previous quartz dislocation creep laws indicating operation of dislocation creep. In contrast, the stress exponent determined at high temperatures (800–950°C) is 1.7 ± 0.2 with an activation energy of 183 ± 25 kJ/mol. A fugacity exponent determined at 800°C was 1.0 ± 0.2. All samples show evidence of basal  slip. However, flow strengths at high temperatures also depend on grain size with a small grain size exponent of 0.51 ± 0.13. Mechanical, microstructural, and textural results suggest that deformation occurs by a combination of intracrystalline and grain boundary processes. The flow law determined from the high‐temperature data can be fit by
with stress, σ in MPa, grain size, d in μm,
in MPa, and Tk in Kelvin. At conditions of the middle crust and tectonic strain rates, deformation depends on grain size where the strength is weaker than for pure dislocation creep even for grain sizes >10 μm.
A Robust Estimation of the 3‐D Intraplate Deformation of the North American Plate From GPS
Authors: Kreemer Corné , Hammond William C. , Blewitt Geoffrey
Published: May 2018

Glacial isostatic adjustment (GIA) is the main cause of deformation in intraplate North America. Here we use up to 3,271 Global Positioning System station velocities to image this 3‐D deformation across the entire plate. We apply a new robust strain rate estimation algorithm (median estimation of local deformation), which does not require the assumption that part of the plate is unaffected by GIA, an assumption we show to be false. Our results show extension in the area underneath the Laurentide ice sheet, contrasted with a semiannular belt of horizontal contraction of up to ~4 × 10−9 yr−1 around the former ice sheet. This contractional belt is kinematically linked to an ~1–2 mm yr−1 far‐field horizontal motion directed toward the ice sheet. Our results, together with a new robustly imaged vertical velocity field, are consistent with GIA as the main cause of deformation, although the contractional strain rates around the former ice sheet and the far‐field horizontal velocities are significantly higher than those predicted by the ICE6G_C(VM5a) model. This finding suggests that our results, including the location of reversal in sign of horizontal motion relative to the ice sheet, will be useful to reevaluate the mantle viscosity structure used by GIA models. Besides the GIA‐attributed deformation, we find almost no other region with significant strain accumulation. A plate‐scale spatial correlation between strain rate and seismicity is absent, suggesting that GIA is a limited driver of contemporary seismogenesis and that intraplate seismicity must be attributable to factors other than secular strain accumulation.
Surface Ocean Enstrophy, Kinetic Energy Fluxes, and Spectra From Satellite Altimetry
Authors: Khatri Hemant , Sukhatme Jai , Kumar Abhishek , Verma Mahendra K.
Published: May 2018

Spectra and fluxes of enstrophy and kinetic energy (KE) are estimated in different parts of the midlatitudinal oceans using geostrophic currents derived from altimetry data. The presence of a strong inverse flux of surface KE is confirmed at scales larger than approximately 200 km, whereas a robust enstrophy cascading regime, accompanied by an approximate
KE spectrum, is observed from about 200 to 100 km. The character of fluxes and spectra is shown to compare favorably with those from a comprehensive Earth system model. In addition, as gridded altimeter data are affected by smoothening and interpolation, the qualitative robustness of the results is verified by sensitivity experiments using space and time‐filtered output from the Earth system model. Given the rotational character of the flow, this large‐scale inverse KE and smaller‐scale forward enstrophy transfer scenario is consistent with expectations from three‐dimensional rapidly rotating and strongly stratified turbulence studies as well as detailed analyses of spectra and fluxes in the upper‐level midlatitude troposphere. In further accord with results from the atmosphere, decomposing the currents into stationary and eddy components (demarcated here by variability greater and less than 100 days, respectively), it is seen that, in addition to the eddy‐eddy contribution, the stationary‐eddy and stationary‐stationary fluxes play a significant role in the inverse (forward) flux of KE (enstrophy). Thus, it is quite possible that, from about 200 to 100 km, the altimeter is capturing the rotationally dominated portion of a surface oceanic counterpart of the upper tropospheric Nastrom‐Gage spectrum.
Abrupt Elongation (Stepping) of Negative and Positive Leaders Culminating in an Intense Corona Streamer Burst: Observations in Long Sparks and Implications for Lightning
Authors: Kostinskiy A. Yu. , Syssoev V. S. , Bogatov N. A. , Mareev E. A. , Andreev M. G. , Bulatov M. U. , Sukharevsky D. I. , Rakov V. A.
Published: May 2018

Properties of positive and negative leaders developing in air gaps ranging from 4 to 10 m that were subjected to 100/7,500‐μs voltage impulses were examined using a two‐frame, high‐speed video camera with image enhancement. Abrupt extension (stepping) that culminated in a bright and structured corona streamer burst was observed for both negative (expected for the “classical” stepping process) and positive (expected for the so‐called restrike process) leaders. Selected high‐quality images of five negative and four positive leaders with pronounced corona streamer bursts are presented here. The morphology of corona streamer bursts was essentially independent of polarity. Streamer bursts exhibiting nearly spherical symmetry were observed. For the four positive leaders, the newly added channel sections (steps) were almost straight and had lengths ranging from about 50 to over 120 cm. For the five negative leaders, most of the steps were curved and their 2‐D lengths were some tens of centimeters. It is generally thought that positive leaders in both long sparks and lightning extend continuously or exhibit optically unresolvable steps whose length is comparable to the leader tip size (1 cm or less) and that for sparks only when the absolute humidity is relatively high (>10 g/m3 or so) or voltage rise time is relatively long (around 1 ms or more) can larger steps occur. In this study, both modes of propagation for different branches of the same positive leader were observed.
Stream Dissolved Organic Matter Composition Reflects the Riparian Zone, Not Upslope Soils in Boreal Forest Headwaters
Authors: Ledesma J. L. J. , Kothawala D. N. , Bastviken P. , Maehder S. , Grabs T. , Futter M. N.
Published: May 2018

Despite the strong quantitative evidence that riparian zones (RZs) are the dominant source of dissolved organic carbon (DOC) to boreal streams, there is still a debate about the potential contribution of upslope areas to fluvial carbon export. To shed new light into this debate, we investigated the molecular composition of dissolved organic matter (DOM) in four upslope‐riparian‐stream transects in a Northern Swedish forest catchment using absorbance (A254/A365 and SUVA254) and fluorescence (fluorescence and freshness indices) metrics. Based on these metrics, our results indicate that stream water DOM molecular composition resembles that of RZs and significantly differs from that of upslope areas. The resemblance between stream and riparian DOM was most apparent for the “Dominant Source Layer” (DSL), a narrow RZ stratum that, theoretically, contributes the most to solute and water fluxes to streams. Spectroscopic characterization based on traditional interpretations of the metrics suggested that mineral upslope (podzol) DOM is less aromatic, more microbially derived, and more recently produced than organic riparian (histosol) and stream DOM. We conclude that RZs, and specifically DSLs, are the main sources of DOC to boreal headwater streams and potentially to other streams located in low‐gradient, organic matter‐rich catchments.
What’s the Best Way to Responsibly Collect Ocean Data?
Authors: Hermes Juliet , Pearlman Jay , Buttigieg Pier
Published: May 2018

Evolving and Sustaining Oceans Best Practices Workshop; Paris, France, 15–17 November 2017
Toward More Realistic Modeling of the Mesosphere
Authors: Underwood Emily
Published: May 2018

New study reveals complex behavior of gravity waves in the atmosphere.
Sea Level Rise Threatens Hundreds of Wastewater Treatment Plants
Authors: Underwood Emily
Published: May 2018

Untreated sewage could affect 5 times more people than direct flooding, a new study shows.
Observations of the Interaction and Transport of Fine Mode Aerosols With Cloud and/or Fog in Northeast Asia From Aerosol Robotic Network and Satellite Remote Sensing
Authors: Eck T. F. , Holben B. N. , Reid J. S. , Xian P. , Giles D. M. , Sinyuk A. , Smirnov A. , Schafer J. S. , Slutsker I. , Kim J. , Koo J.‐H. , Choi M. , Kim K. C. , Sano I. , Arola A. , Sayer A. M. , Levy R. C. , Munchak L. A. , O'Neill N. T. , Lyapustin A. , Hsu N. C. , Randles C. A. , Da Silva A. M. , Buchard V. , Govindaraju R. C. , Hyer E. , Crawford J. H. , Wang P. , Xia X.
Published: May 2018

Analysis of Sun photometer measured and satellite retrieved aerosol optical depth (AOD) data has shown that major aerosol pollution events with very high fine mode AOD (>1.0 in midvisible) in the China/Korea/Japan region are often observed to be associated with significant cloud cover. This makes remote sensing of these events difficult even for high temporal resolution Sun photometer measurements. Possible physical mechanisms for these events that have high AOD include a combination of aerosol humidification, cloud processing, and meteorological covariation with atmospheric stability and convergence. The new development of Aerosol Robotic Network Version 3 Level 2 AOD with improved cloud screening algorithms now allow for unprecedented ability to monitor these extreme fine mode pollution events. Further, the spectral deconvolution algorithm (SDA) applied to Level 1 data (L1; no cloud screening) provides an even more comprehensive assessment of fine mode AOD than L2 in current and previous data versions. Studying the 2012 winter‐summer period, comparisons of Aerosol Robotic Network L1 SDA daily average fine mode AOD data showed that Moderate Resolution Imaging Spectroradiometer satellite remote sensing of AOD often did not retrieve and/or identify some of the highest fine mode AOD events in this region. Also, compared to models that include data assimilation of satellite retrieved AOD, the L1 SDA fine mode AOD was significantly higher in magnitude, particularly for the highest AOD events that were often associated with significant cloudiness.