bluuebunny/crossref_metadata_2025 huggingface dataset:
Surgeon peer network characteristics and adoption of new imaging techniques in breast cancer: A study of perioperative MRI
Authors: Tannenbaum Sara S. , Soulos Pamela R. , Herrin Jeph , Pollack Craig E. , Xu Xiao , Christakis Nicholas A. , Forman Howard P. , Yu James B. , Killelea Brigid K. , Wang Shi‐Yi , Gross Cary P.
Published: November 2018

Background

Perioperative MRI has disseminated into breast cancer practice despite equivocal evidence. We used a novel social network approach to assess the relationship between the characteristics of surgeons’ patient‐sharing networks and subsequent use of MRI.

Methods

We identified a cohort of female patients with stage 0‐III breast cancer from the Surveillance, Epidemiology, and End Results (SEER)‐Medicare database. We used claims data from these patients and non‐cancer patients from the 5% Medicare sample to identify peer groups of physicians who shared patients during 2004‐2006 (T1). We used a multivariable hierarchical model to identify peer group characteristics associated with uptake of MRI in T2 (2007‐2009) by surgeons who had not used MRI in T1.

Results

Our T1 sample included 15 149 patients with breast cancer, treated by 2439 surgeons in 390 physician groups. During T1, 9.1% of patients received an MRI; the use of MRI varied from 0% to 100% (IQR 0%, 8.5%) across peer groups. After adjusting for clinical characteristics, patients treated by surgeons in groups with a higher proportion of primary care physicians (PCPs) in T1 were less likely to receive MRI in T2 (OR = 0.81 for 10% increase in PCPs, 95% CI = 0.71, 0.93). Surgeon transitivity (ie, clustering of surgeons) was significantly associated with MRI receipt (P = 0.013); patients whose surgeons were in groups with higher transitivity in T1 were more likely to receive MRI in T2 (OR = 1.29 for 10% increase in clustering, 95% CI = 1.06, 1.58).

Conclusion

The characteristics of a surgeon's peer network are associated with their patients’ subsequent receipt of perioperative MRI.
Estimation of total electricity consumption curves by sampling in a finite population when some trajectories are partially unobserved
Authors: Cardot Hervé , De Moliner Anne , Goga Camelia
Published: November 2018

Millions of smart meters that are able to collect individual load curves, that is, electricity consumption time series, of residential and business customers at fine scale time grids are now deployed by electricity companies all around the world. It may be complex and costly to transmit and exploit such a large quantity of information, therefore it can be relevant to use survey sampling techniques to estimate mean load curves of specific groups of customers. Data collection, like every mass process, may undergo technical problems at every point of the metering and collection chain resulting in missing values. We consider imputation approaches (linear interpolation, kernel smoothing, nearest neighbours, principal analysis by conditional estimation) that take advantage of the specificities of the data, that is to say the strong relation between the consumption at different instants of time. The performances of these techniques are compared on a real example of Irish electricity load curves under various scenarios of missing data. A general variance approximation of total estimators is also given which encompasses nearest neighbours, kernel smoothers imputation and linear imputation methods. The Canadian Journal of Statistics 47: 65–89; 2019 © 2018 Statistical Society of Canada
π‐Stacking Interactions of Graphene‐Coated Cobalt Magnetic Nanoparticles with Pyrene‐Tagged Dendritic Poly(Vinylidene Fluoride)
Authors: Folgado Enrique , Guerre Marc , Mimouni Nidhal , Collière Vincent , Bijani Christian , Moineau‐Chane Ching Kathleen , Caminade Anne‐Marie , Ladmiral Vincent , Améduri Bruno , Ouali Armelle
Published: November 2018

This study investigates the non‐covalent coating of cobalt magnetic nanoparticles (MNPs) involving a graphene surface with pyrene‐tagged dendritic poly(vinylidene fluoride) (PVDF). Dendrimers bearing a pyrene moiety were selected to play the role of spacers between the graphene surface of the MNPs and the PVDF chains, the pyrene unit being expected to interact with the surface of the MNPs. The pyrene‐tagged dendritic spacer 11 decorated with ten acetylenic units was prepared and fully characterized. Azido‐functionalized PVDF chains were then grafted onto each branch of the dendrimer using Huisgen's [3+2] cycloaddition reaction. Next, the association of the resulting pyrene‐tagged dendritic PVDF 13 with commercially available Co/C MNPs by π‐stacking interactions was studied by fluorescence spectroscopy. Evaluated were the stability of the π‐stacking interactions when the temperature increased and the reversibility of the process when the temperature decreased. Also, hybrid MNPs were prepared from pyrene‐tagged dendrimers decorated either with acetylenic functions (11) or with PVDF branches (13), and they were characterized by transmission electron microscopy and comparative elemental analysis was carried out with naked MNPs.
The effects of diet and mating system on reproductive (and post‐reproductive) life span in a freshwater snail
Authors: Auld Josh R.
Published: November 2018

The length of the reproductive life span, along with the number/frequency/magnitude of reproductive events, quantifies an individual's potential contribution to the next generation. By examining reproductive life span, and distinguishing it from somatic life span, we gain insight into critical aspects of an individual's potential fitness as well as reproductive and somatic senescence. Additionally, differentiating somatic and reproductive life spans can provide insight into the existence of a post‐reproductive period and factors that shape its duration. Given the known importance of diet and mating system on resource allocation, I reared individual freshwater snails (Physa acuta) from 22 full‐sib families under a 2 × 2 factorial design that crossed mate availability (available [outcrossing] or not [selfing]) and diet (Spirulina or lettuce) and quantified aspects of the entire life history enabling me to distinguish reproductive and somatic life spans, determine the total number of reproductive events, and evaluate how the reproductive rate changes with age. Overall, mated snails experienced shorter reproductive and somatic life spans; a diet of Spirulina also shortened both reproductive and somatic life spans. A post‐reproductive period existed in all conditions; its duration was proportional to somatic but not reproductive life span. I evaluate several hypotheses for the existence and duration of the post‐reproductive period, including a novel hypothesis that the post‐reproductive period may result from an increase in reproductive interval with age. I conclude that the post‐reproductive period may be indicative of a randomly timed death occurring as the interval between reproductive events continues to increase. As such, a “post‐reproductive” period can be viewed as a by‐product of a situation where reproductive senescence outpaces somatic senescence.
A patchy continuum? Stream processes show varied responses to patch‐ and continuum‐based analyses
Authors: Collins Sean E. , Matter Stephen F. , Buffam Ishi , Flotemersch Joseph E.
Published: November 2018

Many conceptual syntheses in ecology and evolution are undergirded by either a patch‐ or continuum‐based model. Examples include gradualism and punctuated equilibrium in evolution, and edge effects and the theory of island biogeography in ecology. In this study, we sought to determine how patch‐ or continuum‐based analyses could explain variation in concentrations of stream macronutrients and system metabolism, represented by measures of productivity and respiration rates, at the watershed scale across the Kanawha River Basin, USA. Using Strahler stream order (SSO; continuum) and functional process zone (FPZ; patch) as factors, we produced statistical models for each variable and compared model performance using likelihood ratio tests. Only one nutrient (i.e., ) responded better to patch‐based analysis. Both models were significantly better than a null model for ecosystem respiration; however, neither outperformed the other. Importantly, in most cases, a combination model, including both SSO and FPZ, best described observed variation in the system. Our findings suggest that several patch‐ and continuum‐based processes may simultaneously influence the concentration of macronutrients and system metabolism. Nutrient spiraling along a continuum and the patch mosaic of land cover may both alter macronutrients, for example. Similarly, increases in temperature and discharge associated with increasing SSO, as well as the differences in light availability and channel morphology associated with different FPZs, may influence system metabolism. For these reasons, we recommend a combination of patch‐ and continuum‐based analyses when modeling, analyzing, and interpreting patterns in stream ecosystem parameters.
Epifaunal diversity patterns within and among seagrass meadows suggest landscape‐scale biodiversity processes
Authors: Whippo Ross , Knight Nicole S. , Prentice Carolyn , Cristiani John , Siegle Matthew R. , O'Connor Mary I.
Published: November 2018

Coastal seascapes can support high animal diversity and secondary productivity that attracts conservation interest and provides ecosystem services. Though the importance of spatial structure in marine habitats is well known, determining the dominant spatial scale for biodiversity patterns is an often‐overlooked dimension of the ecological and conservation value of seagrass meadows. We estimated biodiversity patterns at fine (0.28 m2), meadow and seascape scales to explore whether seagrass‐associated biodiversity patterns are consistent with spatial processes such as abiotic habitat filtering or metacommunity dynamics in a northeast Pacific seascape. In Barkley Sound, British Columbia, we quantified epifaunal biodiversity on eelgrass (Zostera marina) to test three hypotheses: Taxonomic diversity and composition (1) vary randomly within meadows but (2) vary systematically among meadows reflecting meadow location or environmental conditions, and (3) spatial patterns are stable over time. We sampled epifaunal invertebrates in a systematic spatial grid within nine eelgrass meadows. We found that epifaunal community composition varied as much over a few meters within the same meadow as among meadows separated by kilometers and of different sizes and wave exposures. In each meadow, we observed less than three‐quarters of the species in the regional species pool, and we observed non‐random spatial aggregation within many species. Even with spatial turnover, assemblages were more similar than predicted by null models based on random species distributions, suggesting that some species tend to co‐occur in high abundance. These spatial biodiversity patterns were not clearly explained by meadow location, area, or abiotic conditions, except that there were differences in clusters of meadows distinguished by their salinity (more marine vs. more fresh). Our results indicate that effective conservation and understanding of how seagrass can support high biodiversity and ecosystem function may require consideration of spatial connections among meadows, and not just the condition of the meadows themselves.
Bayesian vector transmission model detects conflicting interactions from transgenic disease‐resistant grapevines
Authors: Zeilinger Adam R. , Turek Daniel , Cornara Daniele , Sicard Anne , Lindow Steven E. , Almeida Rodrigo P. P.
Published: November 2018

Effective management of vector‐borne plant pathogens often relies on disease‐resistant cultivars. While heterogeneity in host resistance and in pathogen population density at the host population level plays important and well‐recognized roles in epidemiology, the effects of resistance traits on pathogen distribution at the individual host level, and the epidemiological consequences in turn, are poorly understood. Transgenic disease‐resistant plants that produce bacterial diffusible signaling factor (DSF) could provide resistance to the vector‐borne bacterium Xylella fastidiosa by impeding plant colonization and reducing virulence. However, the effects of constitutive in planta production of DSF on insect vector transmission have remained unresolved. We investigated the transmission biology of X. fastidiosa in DSF and wild‐type (WT) grapevines with the efficient vector Graphocephala atropunctata. We also developed a novel Bayesian hierarchical model to improve statistical inference on the multiple components of the vector transmission process. We found that insect vectors had a greater colonization efficiency on DSF plants—meaning they acquired a greater population size of X. fastidiosa—than on WT plants. However, DSF plants also maintained much lower X. fastidiosa populations. These apparently conflicting processes resulted in a lower but highly variable probability of transmission from DSF plants compared to WT plants. Our Bayesian model improved statistical inference compared to widely used frequentist statistics in part by estimating and correcting for imperfect detection of X. fastidiosa in plant and insect tissues. Overall, our results support current models on the roles that DSF plays in vector transmission of X. fastidiosa. In line with our hypothesis, DSF production reduced mean X. fastidiosa population density but increased heterogeneity within host plants. While DSF‐producing plants could potentially improve disease management, our results suggest that they could, under some conditions, facilitate X. fastidiosa spread.
Sodium‐glucose cotransporter 2 inhibitor plus pioglitazone vs pioglitazone alone in patients with diabetes mellitus: A systematic review and meta‐analysis of randomized controlled trials
Authors: Liao Hung‐Wei , Wu Yi‐Ling , Sue Yuh‐Mou , Lee Meng , Ovbiagele Bruce
Published: November 2018

Aims

To evaluate the efficacy and safety of combined therapy with sodium‐glucose cotransporter 2 (SGLT‐2) inhibitors plus pioglitazone versus pioglitazone alone in type 2 diabetic patients.

Materials and Methods

Systematic literature searches were performed across PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and clinicaltrials.gov from 1966 to September 2018 to identify randomized, controlled trials. Mean difference (MD) or odds ratio (OR) was used to evaluate efficacy and safety end‐points (active group vs control group), wherever appropriate. Heterogeneity was assessed by P value of χ2 statistics and I2.

Results

Four randomized controlled trials with 1411 diabetic patients were included. Pooling data from included trials showed that HbA1c change was significantly larger in both low‐dose SGLT‐2 inhibitors (MD: −0.59%, 95% CI: −0.77 to −0.41%) and high‐dose SGLT‐2 inhibitors (MD: −0.65%, 95% CI: −0.78 to −0.53%) plus pioglitazone than pioglitazone alone in 24‐26 weeks. Favourable outcomes were also found in fasting blood glucose level reduction and more patients achieving HbA1c <7% in SGLT‐2 inhibitor plus pioglitazone (OR: 3.21, 95% CI: 1.99 to 5.16). Also, SGLT‐2 inhibitor plus pioglitazone vs pioglitazone, reduced weight and blood pressure. The risks of death, heart failure, hypoglycaemia and urinary tract infection were not different between active and control groups although genital tract infection was more frequently seen in SGLT‐2 inhibitor group.

Conclusions

Compared to pioglitazone alone, SGLT‐2 inhibitor plus pioglitazone improved glycaemic control, reduced body weight and lowered blood pressure, but increased genital tract infection.
Spatial avoidance as a response to contamination by aquatic organisms in nonforced, multicompartmented exposure systems: A complementary approach to the behavioral response
Authors: Araújo Cristiano V.M. , Blasco Julián
Published: November 2018

The idea that the hazard of contaminants is exclusively related to their toxic effects does not consider the fact that some organisms can avoid contamination, preventing toxicity. Although inferences about avoidance are made in most behavioral ecotoxicology studies, assessment of the real spatial displacement (organisms moving toward another habitat to escape contamination) is difficult due to the type of exposure (confined and mandatory) used in the bioassays: a forced exposure approach. A complementary approach using nonforced exposure systems to assess how contaminants affect the spatial distribution of organisms in a bicompartmented (toxic or nontoxic) environment has long been described. Recently, this nonforced approach has been developed to include a multi compartmented system in which different samples can be simultaneously tested. The aim of the present review was to describe the importance of the nonforced, multicompartmented exposure approach to simulate a gradient or patches of contamination, to describe the 2 main exposure systems, and to highlight the ecological relevance of including spatial avoidance and habitat preference in ecotoxicological studies. The multicompartmentalization of the system makes it possible to simulate more complex scenarios and therefore include new ecological concepts in bioassays. We also contrasted spatial avoidance in the nonforced exposure systems with the behavioral endpoints measured under other exposure systems. Finally, we showed that the nonforced, multicompartmented exposure approach makes it possible 1) to improve environmental risk assessments by adding the dispersion pattern of organisms in a multihabitat scenario, and 2) to integrate ecological concepts such as recolonization of recovering habitats, loss of habitat connectivity, habitat fragmentation, and contamination-driven metapopulation, which have received limited attention in ecotoxicological studies. Environ Toxicol Chem 2019;38:312–320. © 2018 SETAC
Dietary source of saturated fat and percentage body fat of patients with type 2 diabetes mellitus: A cross‐sectional study
Authors: Duarte Camila Kümmel , dos Santos Ana Luiza Teixeira , Kirst Claudia , Nunes Graziela da S. , de Franceschi Karine , de Azevedo Mirela Jobim , Zelmanovitz Themis
Published: November 2018

Background

The influence of dietary fat on the body fat of patients with diabetes is not well established. This cross‐sectional study aimed to analyze the association between percentage body fat (PBF) and dietary sources of fat from the usual diet of patients with type 2 diabetes.

Methods

Outpatients were submitted to PBF evaluation estimated by bioelectrical impedance. The patient's usual diet was assessed by a 3‐day weighed diet record (WDR), and compliance was analyzed by comparing the protein intake estimated from the WDR and that from 24‐hr urinary nitrogen output.

Results

A total of 188 patients with type 2 diabetes (aged 62.5 ± 8.8 years; 57% female, body mass index [BMI] 29.3 ± 3.8 kg/m²) were analyzed and divided into groups with high and low PBF according to mean PBF (men: 26.6 ± 7.1%; women: 39.8 ± 5.9%). Patients with high PBF consumed an increased proportion of red meat (52.0% of total meat), processed meat (5.4%), and saturated fat from red meat (2.1% of energy) compared to low PBF individuals (42.3% [p = 0.036]; 3.0% [p = 0.010]; 1.5% of energy [p = 0.032], respectively). According to Poisson's regression, the consumption of red meat (PR = 1.008 [95% CI = 1.002–1.013]; p = 0.006) and the reuse of frying oil (PR = 1.670 [95% CI = 1.240–2.249]; p = 0.001) were associated with higher PBF. In the adjusted analysis, the upper tertile of processed meat intake was associated with higher PBF (PR = 1.522 [95% CI = 1.226–1.891]; p = 0.001) compared to the lower tertile.

Conclusions

The present study suggested that a higher ingestion of dietary sources of saturated fat was associated with high PBF in patients with type 2 diabetes.
Treatment adherence as a mediator of blood pressure control in Chinese older adults with depression
Authors: Xue Jiang , Conwell Yeates , Tang Wan , Bogner Hillary R. , Li Yue , Jiang Yuxing , Zhu Tingfei , Chen Shulin
Published: November 2018

Objectives

Both depression and hypertension (HTN) are prevalent, costly, and destructive, and frequently coexist among the aging population of China. This study aimed to examine the role that treatment adherence plays in blood pressure control in older adult Chinese with depression.

Methods

Data for these analyses were taken from a randomized control trial of a collaborative depression care management intervention conducted in rural villages of Zhejiang Province, China with older adults who had comorbid depression and HTN. They included baseline assessments of 2362 subjects ages ≥60 years, whose blood pressure and depression were measured using a calibrated manual sphygmomanometer and the Chinese version of the 17‐item Hamilton Depression Rating Scale (HDRS‐17), respectively. Treatment adherence was identified by a single question asking whether patients on occasion did not take their medicine.

Results

Uncontrolled HTN was associated with older age (t = 3.10, P<0.01), higher HDRS‐17 score (t = 5.76, P<0.01), and higher rates of non‐adherence to HTN treatment (χ2 = 21.34, P<0.01). Logistic regression models indicated that adherence accounted for 39.4% of the total effect between depression and HTN. Specifically, those with poor adherence were at 1.417 greater odds of having their HTN uncontrolled compared with those with good adherence.

Conclusions

Hypertension control in older adults with depression is complicated by nonadherence to treatment. In addition to diagnosing and treating depression in their older adult patients, primary care physicians can optimize blood pressure control by identifying and addressing their patients' adherence to recommendations for HTN management.
The role of the memory service in helping carers to prepare for end of life: A mixed methods study
Authors: Moore Kirsten J. , Goodison Hannah , Sampson Elizabeth L.
Published: November 2018

Objectives

The objective of the study is to explore current practice and the role taken by UK memory services in helping carers of people with dementia prepare for the end of life.

Methods

We used mixed methods including a survey (48 responses/51% response rate) and semistructured interviews (n = 12) with clinicians working in UK memory services accredited by the Memory Services National Accreditation Programme. We used descriptive statistics to report survey findings and thematically analysed interview and survey qualitative data.

Results

Surveys: services routinely discussed with carers the progressive nature of dementia (89%), legal arrangements (health: 72%; finances: 74%), advance care planning (63%), and implications of loss of capacity (61%). Fewer services routinely discussed the terminal nature of dementia (41%) and meaning of death (11%) with carers. Most (89%) agreed that these conversations were in line with their role. Interview findings corresponded with survey findings. Themes included diagnosis considered too early to discuss end of life, discussions being inconsistent with a “living well” approach, people with dementia being resistant to conversations, and discussions of spirituality crossing professional boundaries. Services' capacity for follow‐up with carers impacted on ability to broach these topics.

Conclusions

More in‐depth and distressing topics such as end of life and advance care planning require longer follow‐up to establish relationships to broach difficult topics. Variability in follow‐up practices between services created inequity in the extent to which memory services could address these topics. More research is required to investigate the best method for broaching these topics with carers and the person with mild dementia within different health care contexts.
Scale‐dependent Poiseuille flow alternatively explains enhanced dispersion in geothermal environments
Authors: Zheng Lizhi , Wang Lichun
Published: November 2018

Fluid flow exerts a critical impact on the convection of thermal energy in geological media, whereas heat transport in turn affects fluid properties, including fluid dynamic viscosity and density. The interplay of flow and heat transport also affects solute transport. To unravel these complex coupled flow, heat, and solute transport processes, here, we present a theory for the idealized scale‐dependent Poiseuille flow model considering a constant temperature gradient (∇T) along a single fracture, where fluid dynamic viscosity connects with temperature via an exponential function. The idealized scale‐dependent model is validated based on the solutions from direct numerical simulations. We find that the hydraulic conductivity (K) of the Poiseuille flow either increases or decreases with scales depending on ∇T > 0°C/m or ∇T < 0°C/m, respectively. Indeed, the degree of changes in K depends on the magnitude of ∇T and fracture length. The scale‐dependent model provides an alternative explanation for the well‐known scale‐dependent transport problem, for example, the dispersion coefficient increases with travel distance when ∇T > 0°C/m according to the Taylor dispersion theory, because K (or equivalently flux through fractures) scales with fracture length. The proposed theory unravels intertwined interactions between flow and transport processes, which might shed light on understanding many practical geophysical problems, for example, geothermal energy exploration.
Cone‐Beam Computed Tomography of Osteogenesis Imperfecta Types III and IV: Three‐Dimensional Evaluation of Craniofacial Features and Upper Airways
Authors: Reznikov Natalie , Dagdeviren Didem , Tamimi Faleh , Glorieux Francis , Rauch Frank , Retrouvey Jean‐Marc
Published: November 2018

This cross‐sectional study investigated the natural history of craniofacial deformities in osteogenesis imperfecta (OI) and determined the impact of three‐dimensional (3D) analysis on diagnosis and treatment planning in orthodontics and orthognathic surgery in comparison to conventional two‐dimensional (2D) cephalometric examination. 3D images of the craniofacial complex were acquired during 1 calendar year using cone‐beam computed tomography (CBCT) from a cohort of 41 individuals (aged 11 to 35 years; 28 females) with OI type III (n = 13) or IV (n = 28). 3D evaluation of the craniocervical junction and upper airways was conducted using InVivoTM. 2D lateral cephalogram was constructed, traced, and examined using the University of Western Ontario analysis (DolphinTM). Quantitative and qualitative parameters were compared between OI type III and type IV groups (unpaired t test) and the unaffected population (Z‐score). 3D evaluation revealed a high prevalence of craniocervical abnormalities, craniofacial asymmetries, and nasal septum deviation in both OI groups. Mean airway dimensions were comparable to the non‐affected population norms, except for 5 individuals who had insufficient airway dimensions. In 2D, the maxilla was retrognathic and hypoplastic, and the mandibular position was convergent with respect to the face, resulting in mandibular prognathism and face height reduction. The 2D trends were more pronounced in OI type III, whereas the 3D craniocervical and airway abnormalities were common in both types. This study illustrates the prevalence of craniofacial and airway anomalies in OI that occur along with facial deformities are not associated with postcranial phenotype and OI type, are apparent only in 3D evaluation, and are likely to influence treatment strategy. For OI patients, a team effort involving a dentist, orthodontist, neurologist, and ear‐nose‐throat (ENT) practitioner is recommended for successful management of craniofacial deformities. © 2018 The Authors JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.
Sulfonic acid anchored on silica, SiO2@SO3H: A superior solid acid catalyst for quick and solvent‐free reductive‐deoxygenation of ketones with NaBH3CN
Authors: Zeynizadeh Behzad , Kouhkan Mehri
Published: November 2018

NaBH3CN as a modified hydroborate agent and due to a strong withdrawing CN group does not show any reducing ability to reduce functional groups in the absence of acidic media (pH ~ 3–4). In this study, the immobilized sulfonic acid on silica, SiO2@SO3H, was prepared and applied as a new solid acid catalyst for extremely enhancing the reducing ability of NaBH3CN. The influence of SiO2@SO3H was highlighted by performing the quick and green reduction of structurally diverse carbonyl compounds involving aldehydes, ketones, α,β‐unsaturated enals and enones, α‐diketones, and acyloins to the corresponding alcohols or alkanes with NaBH3CN. By the NaBH3CN/SiO2@SO3H system, aldehydes were reduced to the corresponding alcohols and ketonic compounds to alkanes as reductive‐deoxygenation products. All reduction reactions were carried out within 3 min at room temperature and under solvent‐free conditions to afford the products in high to excellent yields (90–98%).
Kinematic assessment of an elastic‐core cervical disc prosthesis in one and two‐level constructs
Authors: Guyer Richard D. , Voronov Leonard I. , Havey Robert M. , Khayatzadeh Saeed , Carandang Gerard , Blank Kenneth R. , Werner Stephanie , Rubin Josh , Padovani Nick , Patwardhan Avinash G.
Published: November 2018

Introduction

Anterior cervical discectomy and fusion has been associated with the development of adjacent segment degeneration (ASD), with clinical incidence of approximately 3% per year. Cervical total disc arthroplasty (TDA) has been proposed as an alternative to prevent ASD.

Hypotheses

TDA in optimal placement using an elastic‐core cervical disc (RHINE, K2M Inc., Leesburg, Virginia) will replicate natural kinematics and will improve with optimal vs anterior placement.

Methods

Seven C3‐T1 cervical cadaver spines were tested intact first, then after one‐level TDA at C5‐C6 anterior placement, after TDA at C5‐C6 optimal placement, after two‐level TDA at C5‐C6 and C6‐C7 optimal placement, and finally after two‐level TDA at C5‐C6 lateral placement and C6‐C7 optimal placement. The specimens were subjected to: Flexion‐Extension moments (+1.5 Nm) with compressive preloads of 0 N and 150 N, lateral bending (LB) and axial rotation (AR) (+1.5 Nm) without preload.

Results

C5‐C6 TDA in optimal placement resulted in a non‐significant increase in flexion‐extension ROM compared to intact under 0 N and 150 N preload (P > 0.05). Both LB and AR ROM decreased with arthroplasty (P < 0.01). Optimal placement of C6‐C7 TDA resulted in an increase in flexion‐extension ROM with preload compared to intact (P < 0.05) while LB and AR ROM decreased with arthroplasty (P < 0.01).

Conclusion

This six degree of freedom elastic‐core disc arthroplasty effectively restored flexion‐extension motion to intact levels. In LB the TDA maintained 42% ROM at C5‐C6 and 60% at C6‐C7. In AR 57% of the ROM was maintained at C5‐C6 and 70% at C6‐C7. These findings are supported by literature which shows cervical TDA results in restoration of approximately 50% ROM in LB and AR, which is a multifactorial phenomenon encompassing TDA design parameters and anatomical constraints. Anterior placement of this viscoelastic TDA device shows motion restoration similar to optimal placement suggesting its design may be less sensitive to suboptimal placement.
Preparation of a monolithic column with a mixed‐mode stationary phase of reversed‐phase/hydrophilic interaction for capillary liquid chromatography
Authors: Zhang Meng , Gong Li , Liu Guizhen , Kang Jingwu
Published: November 2018

A monolithic capillary column with a mixed‐mode stationary phase of reversed‐phase/hydrophilic interaction chromatography was prepared for capillary liquid chromatography. The monolith was created by an in‐situ copolymerization of a homemade monomer N,N‐dimethyl‐N‐acryloxyundecyl‐N‐(3‐sulfopropyl) ammonium betaine and a crosslinker pentaerythritol triacrylate in a binary porogen agent consisting of methanol and isopropanol. The functional monomer was designed to have a highly polar zwitterionic sulfobetaine terminal group and a hydrophobic long alkyl chain moiety. The composition of the polymerization solution was systematically optimized to permit the best column performance. The columns were evaluated by using acidic, basic, polar neutral analytes, as well as a set of alkylbenzenes and Triton X100. Very good separations were obtained on the column with the mixed‐mode stationary phase. It was demonstrated that the mixed‐mode stationary phase displayed typic dual retention mechanisms of reversed‐phase/hydrophilic interaction liquid chromatography depending on the content of acetonitrile in the mobile phase. The method for column preparation is reproducible.
Long‐term swallowing performance following transoral robotic surgery for obstructive sleep apnea
Authors: Paker Miki , Duek Irit , Awwad Faten , Benyamini Limor , Meshyeev Tsipi , Gil Ziv , Cohen Jacob T.
Published: November 2018

Objectives/Hypothesis

This study aimed to evaluate the long‐term swallowing performance following transoral robotic surgery (TORS) to the base of tongue (BOT) in the treatment of obstructive sleep apnea (OSA).

Study Design

Retrospective and prospective cohort study.

Methods

Data analysis of 39 patients who underwent BOT reduction via TORS to treat OSA at our center from September 2013 to April 2016. Long‐term swallowing functions were assessed using subjective self‐evaluated swallowing disturbances questionnaire (SDQ) and objective fiberoptic endoscopic evaluation of swallowing (FEES).

Results

Seven patients underwent TORS BOT reduction alone, whereas 32 had also uvulopalatoplasty ± tonsillectomy, with a surgical success rate of 71.4%. Mean time for swallowing evaluation was 27.4 ± 9.43 months. Twenty‐five patients completed the SDQ with an average score of 9.26 ± 10.05. In 32%, the SDQ was positive for dysphagia. In 10 out of 14 patients who underwent FEES, swallowing problems were noticed. The most common pathological findings were food residue in the vallecula followed by early spillage of food into the hypopharynx, penetration of solid food and liquid on the vocal folds surface, and aspiration.

Conclusions

BOT reduction via TORS has a negative effect on long‐term swallowing function. A self‐assessment questionnaire can help detect patients who suffer from swallowing impairment. Postoperative objective swallowing tests are essential not only in the immediate postoperative period but also during late routine follow‐up. Proper patient selection and detailed information about surgery and possible late‐swallowing effect are important factors before scheduling BOT reduction via TORS for OSA treatment.

Level of Evidence

4 Laryngoscope, 129:422–428, 2019
Real‐time robotic airway measurement: An additional benefit of a novel steady‐hand robotic platform
Authors: Razavi Christopher R. , Creighton Francis X. , Wilkening Paul R. , Peine Joseph , Taylor Russell H. , Akst Lee M.
Published: November 2018

Objective

Describe the secondary capability of a robotic system to provide real‐time measurements of airway dimensions with high fidelity.

Methods

Seven unique phantoms of laryngotracheal stenosis (LTS) were modeled using a computer‐aided design tool and were three dimensionally printed. These stenoses were of different dimensions and orientations, and some were purposefully oblique. The dimensions of the stenoses were then measured with the novel Robotic ENT (Ear, Nose, and Throat) Microsurgery System (REMS; Galen Robotics, Inc., Sunnyvale, CA) because it is capable of tool position memory in three dimensional (3D) space. Five participants (two laryngologists, two otolaryngology–head and neck surgery residents, one neurotology fellow) measured each axis of stenosis (anteroposterior, lateral, and craniocaudal) three times for each of the seven stenosis phantoms. These measurements were then compared to the known design dimensions. Mean magnitude of error (MOE) and interrater reliability (IRR) using an intraclass correlation coefficient (ICC) were then calculated.

Results

Mean MOE and standard deviation for all measurements was 0.306 ± 0.247 mm. Mean MOE was 0.374 ± 0.292 mm, 0.300 ± 0.237 mm, and 0.244 ± 0.185 mm for the anteroposterior, lateral, and craniocaudal dimensions of stenosis, respectively. Eighty‐two percent of all measurements had MOE < 0.5 mm. ICC was 0.945 (95% confidence interval [CI]: 0.847–0.989), 0.995 (95% CI: 0.984–0.999), and 0.993 (95% CI: 0.987–0.999) for anteroposterior, lateral, and craniocaudal dimensions, respectively, indicating excellent agreement among participants.

Conclusion

The REMS can be used to reliably and accurately measure airway dimensions in 3D regardless of the orientation of stenosis. This ability may be easily extrapolated to the measurement of any airway lesion during laryngotracheal surgery.

Level of Evidence

4 Laryngoscope, 129:324–329, 2019
Dysfunctional hypoglossal nerve stimulator after electrical cardioversion: A case series
Authors: Vasconcellos Adam P. , Huntley Colin T. , Schell Amy E. , Soose Ryan J. , Boon Maurits S.
Published: November 2018

Objectives/Hypothesis

Upper airway stimulation has demonstrated marked improvements in apnea‐hypopnea index, oxygen desaturation index, and quality‐of‐life measures in patients with moderate to severe obstructive sleep apnea (OSA) who cannot tolerate continuous positive airway pressure. Cardiac arrhythmias are common in patients with OSA and can require electrical cardioversion. We describe the first four reported cases of hypoglossal nerve stimulator (HGNS) dysfunction after electrical cardioversion and illustrate our operative approach to device troubleshooting and repair.

Study Design

Retrospective case series.

Methods

A retrospective review of 201 HGNS implantations performed at two academic institutions revealed four cases of HGNS device dysfunction after electrical cardioversion requiring surgical revision. Preoperative and postoperative device performance metrics and electrical cardioversion specifications were retrospectively assessed and compiled for this case series. The senior authors (R.J.S., M.S.B.) detail operative planning and approach for HGNS implantable pulse generator (IPG) replacement.

Results

At least two patients with HGNS device dysfunction had received cardioversion via anterolateral electrode pad placement. Three patients had received multiple shocks. All four patients experienced a change in device functionality or complete cessation of functionality after electrocardioversion. Operatively, each patient required replacement of the IPG, with subsequent intraoperative interrogation revealing proper device functionality.

Conclusion

Counseling for patients with HGNS undergoing external electrical cardioversion should include possible device damage and need for operative replacement. Anteroposterior electrode pad placement should be considered for patients with HGNS who require electrocardioversion. Operative replacement of an HGNS system damaged by electrocardioversion begins with IPG replacement and intraoperative device interrogation.

Level of Evidence

4

Laryngoscope, 129:1949–1953, 2019
Effect of solution annealing on the microstructure evolution and corrosion behavior of 2205 duplex stainless steel
Authors: Zhang Jiantao , Hu Xiaojun , Lin Ping , Chou Kuochih
Published: November 2018

The effects of solution annealing temperature and isothermal time on the phase composition evolution and corrosion behavior were investigated by employing energy dispersive spectrometry, potentiodynamic polarization measurements, electrochemical impedance spectroscopy, and Mott–Schottky analysis. The pit morphologies were observed by a digital VHX‐5000 with a visible 3D microscopy system. The highest corrosion resistance and most stable passive films were obtained for specimen solution annealing at 1075 °C. Additionally, the solution time had a significant influence on the microstructure evolution and corrosion resistance of the duplex stainless steel. The largest impedance values were exhibited, revealing the best stability with a superior corrosion resistance of the films. The depth and size of pits that occurred on austenite were smaller than those on ferrite. The phase proportion on the microstructure and redistribution of the alloying elements caused by duplex interdiffusion solution annealing simultaneously affected the density of defects and the stability of the passive film, which determined the corrosion resistance. However, the semiconductor properties of the passive films were not affected.
Correction of B0 eddy current effects in spiral MRI
Authors: Robison Ryan K. , Li Zhiqiang , Wang Dinghui , Ooi Melvyn B. , Pipe James G.
Published: November 2018

Purpose

B0 eddy currents are a subtle but important source of artifacts in spiral MRI. This study illustrates the importance of addressing these artifacts and presents a system response‐based eddy current correction strategy using B0 eddy current phase measurements on a phantom.

Methods

B0 and linear eddy current system response measurements were estimated from phantom‐based measurement and used to predict residual eddy current effects in spiral acquisitions. The measurements were evaluated across multiple systems and gradient sets. The corresponding eddy current corrections were studied in both axial spiral‐in/out TSE and sagittal spiral‐out MPRAGE volunteer data.

Results

Correction of B0 eddy currents using the proposed method mitigated blurriness in the axial spiral‐in/out images and artifacts in the sagittal spiral‐out images. The system response measurement was found to yield repeatable results over time with some variation in the B0 eddy current responses measured between different systems.

Conclusions

The proposed eddy current correction framework was effective in mitigating the effects of residual B0 and linear eddy currents. Any spiral acquisition should take residual eddy currents into account. This is particularly important in spiral‐in/out acquisitions.
Requiem for a Dream: On Advancing Human Rights via Internet Architecture
Authors: Mueller Milton L. , Badiei Farzaneh
Published: November 2018

A growing number of scholars and policymakers are calling attention to the relationship between technology standards, protocols, human rights, ethics, and values—also claiming that human rights can be secured (or violated) via the Internet's standards and architecture. However, this assertion of governance through Internet architecture can oversimplify the complex relationship between technology and society. This article argues that human rights are primarily a political and institutional accomplishment, not a simple matter of technical design. By articulating a challenge to uncritical and imperfectly theorized efforts to link standards‐setting and protocol development to “values” and human rights objectives, we hope to foster a more realistic approach to Internet standardization and governance processes and a more balanced and well‐informed theoretical debate. Situated in the theoretical literature on science, technology, and society, our analysis is also informed by extensive empirical exposure to standardization and Internet governance processes. It includes two short case studies in which standards development and rights issues have intersected in ways that illuminate the relationship between rights and standards, and which can be interpreted to falsify certain claims.
Bayesian sample size determination for phase IIA clinical trials using historical data and semi‐parametric prior's elicitation
Authors: Berchialla Paola , Zohar Sarah , Baldi Ileana
Published: November 2018

The Simon's two‐stage design is the most commonly applied among multi‐stage designs in phase IIA clinical trials. It combines the sample sizes at the two stages in order to minimize either the expected or the maximum sample size.

When the uncertainty about pre‐trial beliefs on the expected or desired response rate is high, a Bayesian alternative should be considered since it allows to deal with the entire distribution of the parameter of interest in a more natural way.

In this setting, a crucial issue is how to construct a distribution from the available summaries to use as a clinical prior in a Bayesian design.

In this work, we explore the Bayesian counterparts of the Simon's two‐stage design based on the predictive version of the single threshold design. This design requires specifying two prior distributions: the analysis prior, which is used to compute the posterior probabilities, and the design prior, which is employed to obtain the prior predictive distribution. While the usual approach is to build beta priors for carrying out a conjugate analysis, we derived both the analysis and the design distributions through linear combinations of B‐splines.

The motivating example is the planning of the phase IIA two‐stage trial on anti‐HER2 DNA vaccine in breast cancer, where initial beliefs formed from elicited experts' opinions and historical data showed a high level of uncertainty. In a sample size determination problem, the impact of different priors is evaluated.
Risk, Hazards, and Crises in Research: What Risks Get Researched, Where, and How?
Authors: Kuipers Sanneke , van Grieken Bob J. , van Asselt Marjolein B. A.
Published: November 2018

This review article maps the shifts and trends in the risk literature regarding particular risk types across the past 30+ years. Not only does it address which hazards and risks receive scholarly attention, but also from which perspective. A similar review on crisis literature (Kuipers & Welsh, ) reported that on average only 14 percent of the articles in three crisis and disaster journals pertained explicitly to risk research. Does risk research perhaps pay more attention to crises than the other way around? Our multivariate regression analysis of the different types and themes reveals how some risk types are researched and discussed almost exclusively from a particular angle. Also, the large majority of articles from some perspectives only take a limited variety of risks into account. Mapping risk research indicates not only which topics and themes have received increasing or structural attention but also which ones, or which combination of risk types and perspectives, perhaps deserve more study than they currently receive.
A Nontoxic, Bio‐friendly, Fluorescent Chemodosimeter for Hypochlorite Detection in Living Cells through the Oxidation of Hypochlorite on a Hydrazide System
Authors: Sain Dibyendu , Manna Abhishek , Kumari Chanda , Das Mukhopadhyay Chitrangada , Goswami Shyamaprosad
Published: November 2018

A simple, nontoxic, bio‐friendly, fluorescent chemodosimeter based on 2,4‐dinitrobenzene and thio‐rhodamine was designed and synthesized for the detection of toxic hypochlorite with high selectivity and sensitivity. First time, the oxidation property of the hypochlorite ion was applied on a hydrazide system (Ar−NH−N<). Practical utility of the sensor was proved through simple and fast visual detection of hypochlorite. Absorption and emission spectra exhibited the fast sensing capability of the sensor towards hypochlorite. The nontoxic, bio‐friendly properties of the sensor in living cells increased its real time practical applicability as it was successfully applied for in‐vitro detection of toxic hypochlorite in living cells.
The Crystallization Mechanism of the Octahedron‐Like Ce1‐xYbxO2‐x/2 and Ce1‐xLuxO2‐x/2 Ceria‐Based Mixed Oxide.
Authors: Małecka Małgorzata A.
Published: November 2018

The crystal growth process of the octahedron‐like Ce0.95(Yb or Lu)0.05O1.975 was studied by the various techniques. It has been found that the oriented attachment mechanism plays the main role during the crystal growth process. The detailed examination of the crystallite growth process was possible thanks to phosphates‐addition as a thin film on the oxide surface. The octahedron‐like, iso‐oriented crystals are built of the small octahedral mixed oxides crystals via the oriented attachment process. The mechanism of the crystal growth of the pure ceria is probably the same but the there is no thin film of the cerium phosphate on the ceria crystals surface.