bluuebunny/crossref_metadata_2025 huggingface dataset:
Award winner for outstanding research in the PhD category, 2014 society for biomaterials annual meeting and exposition, denver, colorado, april 16–19, 2014: Decellularized adipose matrix hydrogels stimulate in vivo neovascularization and adipose formation
Authors: Adam Young D. , Bajaj Vaibhav , Christman Karen L.
Published: February 2014

Decellularization of tissues offers the ability to produce tissue‐specific extracellular matrix (ECM) scaffolds that recreate many of the biochemical aspects of the tissue of interest. In this study, we describe the in vivo function of decellularized adipose ECM hydrogels for treating subcutaneous adipose deficits. Adipose ECM hydrogels were combined with either adipose‐derived adult stem cells or a biocompatible cross‐linker, injected subcutaneously into nude mice, and evaluated over the course of 1 month. These ECM hydrogels showed improved integration with the surrounding tissue in vivo compared to a clinical standard soft tissue filler, Juvederm, and stimulated neovascularization. More importantly, these adipose ECM hydrogels facilitated new adipose regeneration within the material at 1 month, a feature not seen with current clinical soft tissue fillers. These results contribute to the growing evidence that ECM‐based materials are capable of stimulating subcutaneous adipose regeneration, suggesting that future soft tissue filler materials could incorporate ECM elements in order to restore function to adipose deficits instead of simply filling them with static materials. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 1641–1651, 2014.
Parathyroid Hormone 1-84 Targets Bone Vascular Structure and Perfusion in Mice: Impacts of Its Administration Regimen and of Ovariectomy
Authors: Roche Bernard , Vanden-Bossche Arnaud , Malaval Luc , Normand Myriam , Jannot Martin , Chaux Robin , Vico Laurence , Lafage-Proust Marie-Hélène
Published: February 2014

Bone vessel functions during bone remodeling are poorly understood. They depend on both vessel network structure and vasomotor regulation. Parathyroid hormone (PTH) is a systemic vasodilator that may modulate microvascularization. Moreover, although intermittent PTH is anti-osteoporotic, continuous PTH administration can be catabolic for bone. Finally, ovariectomy (OVX) reduces bone perfusion and vessel density in mice. We reasoned that the effects of PTH on bone vascularization might depend on its administration regimen and be impacted by ovariectomy. A 100-µg/kg PTH 1-84 daily dose was administered for 15 days to 4-month-old female C57BL/6 mice, either as daily sc injection (iPTH) or continuously (cPTH; ALZET minipump). Blood pressure (BP) and tibia bone perfusion were measured in vivo with a laser Doppler device. Histomorphometry of bone and barium-contrasted vascular network were performed on the same tibia. Compared with untreated controls, both iPTH and cPTH increased bone formation but had opposite effects on resorption. Both iPTH and cPTH were slightly angiogenic. Intermittent PTH increased microvessel size (+48%, p < 0.001), whereas cPTH decreased it (–29%, p = 0.009). iPTH increased bone perfusion (27%, p < 0.001) with no change in BP, whereas cPTH did not. The vascular effects of a 15-day iPTH treatment were analyzed in OVX mice and compared with sham-operated and OVX untreated controls. Two other anti-osteoporotic drugs, zoledronate (one injection, 70 µg/kg) and propranolol, (5 mg/kg/d) were tested in OVX mice. Although no change in bone mass was observed, iPTH stimulated bone formation and prevented the OVX-induced reduction in bone perfusion and vessel density. Both zoledronate and propranolol strongly lowered bone turnover, but surprisingly, zoledronate prevented OVX-induced reduction in bone perfusion but propranolol did not. Our integrative approach thus demonstrates that the effects of PTH on bone vessel structure and function depend on its mode of administration as well as on the HPG-axis hormonal status, and that OVX-induced vascular changes are prevented by iPTH. © 2014 American Society for Bone and Mineral Research.
Bite force and feeding kinematics in the eastern North Pacific kyphosidae
Authors: Moran Clinton Joseph , Ferry Lara
Published: February 2014

Some fishes that feed on attached food items possess an intramandibular joint (IMJ), which is thought to increase maximum gape and facilitate contact between the tooth‐bearing surface and the substrate. However, the mechanical consequences of using an IMJ to remove attached food items from the substrate are still poorly understood. We examined the most prominent eastern North Pacific kyphosid, the scraper: Girella nigricans and two other kyphosids, Medialuna californiensis and Hermosilla azurea, which occupy similar habitats. Of the three species, G. nigricans had the highest theoretical bite force per unit length. We examined the feeding mechanics of G. nigricans in two different feeding scenarios: a scraping behavior elicited on a block of brine shrimp gelatin and a picking behavior elicited on Ulva sp. We measured cranial elevation, lower jaw rotation, premaxillary protrusion, premaxillary rotation, gape maximum, and intramandibular rotation. Ulva treatments produced significantly greater cranial rotation, when compared to gelatin treatments. Gelatin treatments were associated with greater lower jaw rotation and larger gape. Premaxillary rotation and premaxillary protrusion did not differ between treatments. Intramandibular rotation occurred only when G. nigricans physically contacted the gelatin, suggesting the IMJ is a passive joint with no associated musculature. We also noted that G. nigricans do not appear to use suction to draw food into the mouth. The lack of suction and the presence of the IMJ suggest that the jaws of G. nigricans are specialized for maximizing jaw force when scraping. J. Exp. Zool. 321A: 189–197, 2014. © 2014 Wiley Periodicals, Inc.
Inlet and outlet valve flow and regurgitant volume may be directly and reliably quantified with accelerated, volumetric phase‐contrast MRI
Authors: Hsiao Albert , Tariq Umar , Alley Marcus T. , Lustig Michael , Vasanawala Shreyas S.
Published: February 2014

Purpose

To determine whether it is feasible to use solely an accelerated 4D phase‐contrast magnetic resonance imaging (4D‐PC MRI) acquisition to quantify net and regurgitant flow volume through each of the cardiac valves.

Materials and Methods

Accelerated, 4D‐PC MRI examinations performed between March 2010 through June 2011 as part of routine MRI examinations for congenital, structural heart disease were retrospectively reviewed and analyzed using valve‐tracking visualization and quantification algorithms developed in Java and OpenGL. Excluding patients with transposition or single ventricle physiology, a total of 34 consecutive pediatric patients (19 male, 15 female; mean age 6.9 years; age range 10 months to 15 years) were identified. 4D‐PC flow measurements were compared at each valve and against routine measurements from conventional cardiac MRI using Bland–Altman and Pearson correlation analysis.

Results

Inlet and outlet valve net flow were highly correlated between all valves (P = 0.940–0.985). The sum of forward flow at the outlet valve and regurgitant flow at the inlet valve were consistent with volumetric displacements in each ventricle (P = 0.939–0.948). These were also highly consistent with conventional planar MRI measurements with net flow (P = 0.923–0.935) and regurgitant fractions (P = 0.917–0.972) at the outlet valve and ventricular volumes (P = 0.925–0.965).

Conclusion

It is possible to obtain consistent measurements of net and regurgitant blood flow across the inlet and outlet valves relying solely on accelerated 4D‐PC. This may facilitate more efficient clinical quantification of valvular regurgitation. J. Magn. Reson. Imaging 2015;41:376–385.© 2013 Wiley Periodicals, Inc.
Multi‐echo gradient recalled echo imaging of the pelvis for improved depiction of brachytherapy seeds and fiducial markers facilitating radiotherapy planning and treatment of prostatic carcinoma
Authors: Schieda Nicola , Avruch Leonard , Shabana Wael M. , Malone Shawn Christopher
Published: February 2014

Purpose

MR localization of implanted devices for radiotherapy (RT) in prostatic carcinoma is critical for treatment planning. This clinical note studies the application of a multi‐echo gradient recalled echo (GRE) pulse sequence with sum of squares echo combination (ME GRE) to enhance detection of seeds and fiducials.

Materials and Methods

Fifteen patients who underwent MRI using fast spin echo (FSE), single‐echo and ME GRE over a 9‐month period were retrospectively evaluated by two readers who assessed overall image quality, depiction of seeds/fiducials and image sharpness using a 5‐point scale (1 = poor, 2 = suboptimal, 3 = adequate, 4 = above average, 5 = excellent). Image scores were compared using the Wilcoxon sign rank test.

Results

In all 15 patients, both readers rated the depiction of seeds/fiducials with ME GRE as excellent. In all 15 patients, overall image quality and image sharpness with ME GRE was rated as excellent by reader 1. In 12/15 patients, overall image quality and image sharpness with ME GRE was rated as excellent and in the other patients above average by reader 2. There was a difference in depiction of seeds/fiducials comparing GRE to FSE (P < 0.001) and ME to single echo GRE (P < 0.001). Overall image quality and sharpness was higher with ME compared with single echo GRE (P < 0.001) and similar to FSE (P = 0.26 and P = 0.16).

Conclusion

Multi‐echo GRE provides better detection of implanted seeds and fiducial markers when compared with both FSE and single‐echo GRE potentially improving RT treatment planning for prostate carcinoma. J. Magn. Reson. Imaging 2015;41:715–720. © 2014 Wiley Periodicals, Inc.
Biochars improve aggregate stability, water retention, and pore‐space properties of clayey soil
Authors: Sun Fangfang , Lu Shenggao
Published: February 2014

The influence of biochar amendments on the physical quality of a clayey soil (Vertisol) was evaluated by aggregate‐size distribution and stability, water retention, and pore‐space structure of biochar‐amended soils. Clayey soil was treated with three kinds of biochars (straw biochar, woodchips biochar, and wastewater‐sludge biochar) at the rate of 0, 20, 40, and 60 g biochar (kg soil)–1 and incubated for 180 d in glasshouse. The application of straw biochar (SB) and wastewater‐sludge biochar (WSB) significantly enhanced the formation of 5–2 and 0.25–0.5 mm macroaggregates in the clayey soil relative to the control treatment, while the < 0.25‐cm microaggregate decreased with biochar additions. However, woodchips biochar (WCB) had no obvious effect on the formation of macroaggregate. The application of SB and WSB increased the mean weight diameter (MWD) and geometric mean diameter (GMD) of clayey soil, implying that biochar increased the aggregate stability. They improved the aggregate stability through an enhanced resistance to slaking and increased interparticular cohesion. The SB‐amended soils exhibited significant increases in the available water contents of soils. The application of SB significantly increased pore volume in the macropore (> 75 μm) and mesopore (30–75 μm) ranges, which may be the result of the reorganization of pore‐size distribution and aggregation processes induced by the addition of biochar. Results indicated that biochar had the potential to improve the physical quality and pore‐space status of clayey soil. It is suggested that biochar may be considered as a soil amendment for improving poor physical characteristics of clayey soil.
Using GPS Supported Speed Analysis to Determine Spatial Visitor Behaviour
Authors: Bauder Michael
Published: February 2014

In this paper a new approach to determine spatial visitor behaviour using GPS‐based measurement of tourists' velocity is given. I prove that GPS‐based velocity measurement is valid and feasible, even in urban areas. Furthermore, I illustrate that the possibility to interpret spatial visitor behaviour, as well as the choice of transportation type, can be drawn out of the recorded data. The suggested procedure delivers several benefits for destination and tourism management, given that the knowledge of spatial visitor behaviour is central to a successful and sustainable destination management. As an example, two studies (Freiburg, Berlin) are presented in this paper. Copyright © 2014 John Wiley & Sons, Ltd.
Nocturnal field use by fall migrating American woodcock in the Delta of Arkansas
Authors: Krementz David G. , Crossett Richard , Lehnen Sarah E.
Published: February 2014

The American woodcock (Scolopax minor) population has declined since the late 1960s across its range and is now considered a species of special concern. Research on woodcock habitat use during migration and migratory routes through the Central Flyway has been limited. We assessed woodcock phenology, estimated density, and nocturnal habitat use in fields on public lands in the lower Mississippi Alluvial Valley portion of Arkansas during November and December of 2010 and 2011. We used all‐terrain vehicles to survey woodcock along transects in 67 fields of 8 field types. We analyzed data using hierarchical distance sampling. We detected woodcock from the first week in November through the third week in December but in low numbers. We did not detect woodcock in millet or rice fields, whereas woodcock had the highest estimated densities in unharvested soybeans. All other crop type–post‐harvest management combinations had low woodcock densities. We did not detect woodcock in fields <8 ha or >40 ha. Woodcock in the lower Mississippi Alluvial Valley may benefit from management for unharvested soybean fields of moderate size (approx. 8–40 ha). © 2014 The Wildlife Society.
Kinetics and Mechanism of the Reduction of Sodium Chlorite by Sodium Hydrogen Ascorbate in Aqueous Solution at Near Neutral pH
Authors: Curtin Maria , Dwyer Sean , Bukvic Dino , Doona Christopher J. , Kustin Kenneth
Published: February 2014

The reduction of chlorite ion by the hydrogen ascorbate ion in a neutral solution safely produces chlorine dioxide. The decrease in absorbance at 268 nm with the presence of dimethyl sulfoxide (DMSO) allows measurement of the ascorbate disappearance in the reaction with excess chlorite. The measured rate constant at 25 ± 0.02°C, 3.67 × 10−4 M DMSO, ionic strength 0.51 M (NaClO4), and in the presence of 3.32 × 10−9 M ethylenediaminetetraacetic acid is 13.81 ± 1.30 M−1 s−1. Rate constant measurements over the range 15–35°C gave an Arrhenius activation energy of 75.51 ± 4.53 kJ mol−1. This result is the first reported determination of the kinetics of this reaction and is consistent with either electron‐ or oxygen‐transfer mechanisms. Anomalously, reduction of chlorite results in its oxidation, because intermediate hypochlorite oxidizes chlorite.
Coblation total tonsillectomy and adenoidectomy versus coblation partial intracapsular tonsillectomy and adenoidectomy in children
Authors: Duarte Victor M. , Liu Yuan F. , Shapiro Nina L.
Published: February 2014

Objectives/Hypothesis

To evaluate the postoperative course of children who underwent coblation T&A versus those who underwent coblation partial intracapsular tonsillectomy and adenoidectomy (PITA).

Study Design

Retrospective cohort study.

Methods

Records of children undergoing consecutive tonsillectomies from July 2009 to October 2012 were analyzed. All surgeries used a coblation device. Outcomes including intraoperative and postoperative bleeding, pain, and return to preoperative diet were analyzed comparing the coblation T&A and coblation PITA patients.

Results

Of 415 patients evaluated, 258 (62.2%) underwent coblation T&A and 157 (37.8%) underwent coblation PITA. Seventeen (4.1%) patients experienced postoperative hemorrhage, 15 (88.2%) of whom underwent T&A and two (11.8%) of whom underwent PITA (P = 0.024). Multivariate analysis demonstrated that coblation T&A was a significant contributor to postoperative hemorrhage, with an odds ratio of 4.8 (95% confidence interval [CI]: 1.08–21.21) compared to coblation PITA. Patients who underwent T&A resumed normal diets significantly later (8 days, SD 4.6) than those who underwent PITA (5.4 days, standard deviation [SD]: 3.4) (P = 0.022). In terms of pain severity, more T&A patients reported “severe” pain and more PITA patients reported “moderate” pain (P = 0.047). More T&A patients experienced a “post‐op dip,” defined as increased pain during postoperative days 5–9, than did PITA patients (P < 0.001).

Conclusions

Coblation PITA is a safe procedure that has a lower incidence of intraoperative and postoperative bleeding in children compared to coblation T&A. Patients may have less pain and return to preoperative diets sooner than those undergoing coblation T&A.

Level of Evidence

4. Laryngoscope, 124:1959–1964, 2014
Endoscopic endonasal approaches to infratemporal fossa tumors: A classification system and case series
Authors: Taylor Robert J. , Patel Mihir R. , Wheless Stephen A. , McKinney Kibwei A. , Stadler Michael E. , Sasaki‐Adams Deanna , Ewend Matthew G. , Germanwala Anand V. , Zanation Adam M.
Published: February 2014

Objectives/Hypothesis

To propose a clinically applicable anatomic classification system describing three progressive endoscopic endonasal approaches (EEAs) to the infratemporal fossa (ITF) and their potential sequelae. Overall feasibility and outcomes of these approaches are presented through a consecutive case series.

Study Design

Description of classification system for EEAs to the ITF and case series.

Methods

A classification system of EEAs to ITF tumors was created based on the senior author's clinical experience and cadaveric dissection. A retrospective chart review of 21 child and adult patients with primary ITF tumors treated by these approaches from 2008 to 2012 at a tertiary‐care academic medical center was conducted.

Results

Three progressive EEAs to ITF tumors were defined: 1) a transpterygopalatine fossa approach, 2) a transmedial pterygoid plate approach, and 3) a translateral pterygoid plate approach. Twenty‐one patients treated with these approaches were identified consecutively, with a mean age of 44.2 years (range, 11–79 years). Tumors primarily involving the pterygopalatine fossa and not the ITF were excluded. Pathology included three advanced juvenile nasopharyngeal angiofibromas, three adenoid cystic carcinomas, two recurrent inverted papillomas, two trigeminal schwannomas, and 11 other diverse skull base pathologies. No intraoperative or postoperative complications occurred, with a mean follow‐up of 21.5 months (range, 1–55 months). Expected potential sequelae such as V2/palatal numbness, Eustachian tube dysfunction, and trismus occurred in 10/21 patients.

Conclusions

EEAs to ITF tumors are technically feasible with low risk of complications for well‐selected patients. The proposed classification system is useful for anticipating potential sequelae for each approach.

Level of Evidence

4 Laryngoscope, 124:2443–2450, 2014
Impact of platybasia and anatomic variance on surgical approaches to the craniovertebral junction
Authors: Burke Kevin , Benet Arnau , Aghi Manish K. , El‐Sayed Ivan
Published: February 2014

Objectives/Hypothesis

The aim of this study was to characterize the anatomic relation of the craniovertebral junction (CVJ) relative to the palatal line (PL), determine if the height of the CVJ over the PL is directly related to the anterior skull base (ASB) angle and the condition of platybasia, and consider the impact of the findings on endoscopic surgical approaches to the skull base.

Study Design

Retrospective radiographic review.

Methods

A retrospective study was performed using patients with chronic rhinosinusitis (CRS) as the control population and patients with platybasia as the study population. Sagittal magnetic resonance imaging and computed tomography were used to measure the ASB angle and the height of the CVJ above or below the PL.

Results

The height of the CVJ relative to the PL is significantly higher in the platybasia group compared to the CRS group. However, a linear relationship is not identified between ASB angle and height of the CVJ relative to the PL. The height of the CVJ relative to the PL shows a wide distribution in both populations extending >1 cm above (platybasia group) and 1 cm below (control group).

Conclusions

Platybasia results in a higher CVJ relative to the PL compared to the general population; however, the relationship is not linear. The wide distribution of the CVJ relative to the PL indicates that the approach selection must be tailored to the patient's specific anatomy.

Level of Evidence

3b Laryngoscope, 124:1760–1766, 2014
Neoplastic meningitis presenting with dysphagia and bilateral vocal cord paralysis
Authors: Dixon Peter R. , Alsaffar Hussain , Symons Sean P. , Enepekides Danny , Higgins Kevin M.
Published: February 2014

Neoplastic meningitis is the infiltration of the leptomeninges and subarachnoid space by tumor cells occurring in 3% to 5% of patients with systemic malignancies. Most cases present with multifocal neurological symptoms that vary according to the central nervous system territory involved. Here, we describe the first reported case to our knowledge of neoplastic meningitis causing bilateral vocal cord paralysis. Early diagnosis of this progressive disease process is essential to achieving a better treatment response and improved survival. This report demonstrates that neoplastic meningitis should be considered in the investigation of bilateral vocal cord paralysis, particularly in patients with a history of metastatic disease. Laryngoscope, 124:1912–1914, 2014
Physiology‐based minimum clinically important difference thresholds in adult laryngotracheal stenosis
Authors: Nouraei S. Mahmoud , Franco Ramon A. , Dowdall Jayme R. , Nouraei S. A. Reza , Mills Heide , Virk Jag S. , Sandhu Guri S. , Polkey Mike
Published: February 2014

Objectives/Hypothesis

Delivering evidence‐based patient care is predicated on the availability of objective and validated outcome measures. We aimed to calculate physiology‐based minimum clinically important difference (MCID) values for adult laryngotracheal stenosis (LTS).

Study Design

Prospective observational study.

Methods

Patient demographics, morbidities, and stenosis severity were assessed preoperatively. Flow‐volume loops and Medical Research Council (MRC) dyspnea grades were measured in 21 males and 44 females before and 6 to 8 weeks after airway surgery, and before treating recurrent disease in 10 patients. Anchor and distribution‐based methodologies were used to calculate MCIDs for treatment efficacy and disease recurrence respectively.

Results

The mean age at treatment was 46 ± 16 years. The most common etiology was idiopathic subglottic stenosis (38%). Most lesions (66%) obstructed >70% of the lumen. There were strong correlations between treatment‐related changes in total peak flow (TPF) (ΔTPF) (peak expiratory flow + |peak inspiratory flow|) and the ratio of area under the flow‐volume loop (AUC) to forced vital capacity (FVC) (ΔAUCTotal/FVC), and treatment‐related changes in the MRC grade (ΔMRC) (r = −0.76 and r = −0.82, respectively). Both TPF and AUCTotal/FVC discriminated between effective (ΔMRC <0) and ineffective (ΔMRC ≥0) interventions, yielding MCID values of 4.2 L/s for TPF and 2.1 L2/s for AUCTotal/FVC, respectively. Ten patients required airway treatment for recurrent disease, and TPF and AUCTotal/FVC levels had distribution‐based MCID values of 0.9 and 0.6, respectively.

Conclusions

Flow‐volume loops provide a quantitative method of objectively assessing outcomes in LTS. TPF is the most convenient index for this purpose, but AUCTotal/FVC provides marginally greater sensitivity and specificity.

Level of Evidence

4 Laryngoscope 124:2313–2320, 2014
A cumulative hierarchy of sets for constructive set theory
Authors: Ziegler Albert
Published: February 2014

The von Neumann hierarchy of sets is heavily used as a basic tool in classical set theory, being an underlying ingredient in many proofs and concepts. In constructive set theories like without the powerset axiom however, it loses much of its potency by ceasing to be a hierarchy of sets as its single stages become only classes. This article proposes an alternative cumulative hierarchy which does not have this drawback and provides examples of how it can be used to prove new theorems in .
Peano Corto and Peano Basso: A Study of Local Induction in the Context of Weak Theories
Authors: Visser Albert
Published: February 2014

In this paper we study local induction w.r.t. Σ1‐formulas over the weak arithmetic . The local induction scheme, which was introduced in , says roughly this: for any virtual class that is progressive, i.e., is closed under zero and successor, and for any non‐empty virtual class that is definable by a Σ1‐formula without parameters, the intersection of and is non‐empty. In other words, we have, for all Σ1‐sentences S, that S implies , whenever is progressive. Since, in the weak context, we have (at least) two definitions of Σ1, we obtain two minimal theories of local induction w.r.t. Σ1‐formulas, which we call Peano Corto and Peano Basso.

In the paper we give careful definitions of Peano Corto and Peano Basso. We establish their naturalness both by giving a model theoretic characterization and by providing an equivalent formulation in terms of a sentential reflection scheme.

The theories Peano Corto and Peano Basso occupy a salient place among the sequential theories on the boundary between weak and strong theories. They bring together a powerful collection of principles that is locally interpretable in . Moreover, they have an important role as examples of various phenomena in the metamathematics of arithmetical (and, more generally, sequential) theories. We illustrate this by studying their behavior w.r.t. interpretability, model interpretability and local interpretability. In many ways the theories are more like Peano arithmetic or Zermelo Fraenkel set theory, than like finitely axiomatized theories as Elementary Arithmetic, and . On the one hand, Peano Corto and Peano Basso are very weak: they are locally cut‐interpretable in . On the other hand, they behave as if they were strong: they are not contained in any consistent finitely axiomatized arithmetical theory, however strong. Moreover, they extend , the theory of parameter‐free Π1‐induction.
Rado's Conjecture and Ascent Paths of Square Sequences
Authors: Todorčević Stevo , Torres Pérez Víctor
Published: February 2014

This is a continuation of our paper where we show that Rado's Conjecture can trivialize ‐sequences in some cases when ϑ is not necessarily a successor cardinal.
Some combinatorial principles for trees and applications to tree families in Banach spaces
Authors: Poulios Costas , Tsarpalias Athanasios
Published: February 2014

Suppose that is a normalized family in a Banach space indexed by the dyadic tree S. Using Stern's combinatorial theorem we extend important results from sequences in Banach spaces to tree‐families. More precisely, assuming that for any infinite chain β of S the sequence is weakly null, we prove that there exists a subtree T of S such that for any infinite chain β of T the sequence is nearly (resp., convexly) unconditional. In the case where is a family of continuous functions, under some additional assumptions, we prove the existence of a subtree T of S such that for any infinite chain β of T, the sequence is unconditional. Finally, in the more general setting where for any chain β, is a Schauder basic sequence, we obtain a dichotomy result concerning the semi‐boundedly completeness of the sequences .
Preparation of Multilayered Polymeric Structures Using a Novel Four‐Needle Coaxial Electrohydrodynamic Device
Authors: Labbaf Sheyda , Ghanbar Hanif , Stride Eleanor , Edirisinghe Mohan
Published: February 2014

Coaxial four‐needle electrohydrodynamic forming is applied for the first time to prepare layered structures in both particle and fiber form. Four different biocompatible polymers, polyethylene glycol, poly (lactic‐co‐glycolic acid), polycaprolactone, and polymethylsilsesquioxane, are used to generate four distinct layers confirmed using transmission and scanning electron microscopy combined with focused ion beam milling. The incorporation and release of different dyes within the polymeric system of four layers are demonstrated, something that is much desired in modern applications such as the polypill where multiple active pharmaceutical ingredients can be combined to treat numerous diseases.

image
Aziridine Termination of Living Anionic Polymerization
Authors: Thomi Laura , Wurm Frederik R.
Published: February 2014

A switch from carbanions to aza‐anions is performed by the addition of N‐tosylaziridine (TAz) to living poly(styryl) (PS) chains. This is the first example of carbanionic aziridine ring‐opening which was previously activated by amidation with a tosyl group to enable nucleophilic ring‐opening by the living chain end. Poly(styrene)‐tosylaziridines (PS‐TAz) with narrow molecular weight distributions and variable molecular weights are synthesized. The removal of the tosyl group and subsequent functionalization is shown, evidencing quantitative transfer to azaanionic species. All polymers are characterized in detail by 1H NMR spectroscopy, DOSY 1H NMR spectroscopy, and size exclusion chromatography (SEC). This strategy allows the introduction of amine groups via anionic polymerization in analogy to the well‐established epoxide termination.

image
Polymer Nanoparticles Based on Pyrene‐Functionalized Poly(acrylic acid) for Controlled Release under Photo and pH Stimulation
Authors: Feng Ning , Dong Jie , Han Guoxiang , Wang Guojie
Published: February 2014

A novel photo and pH‐responsive amphiphilic pyrene‐functionalized polymer is synthesized by the esterification reaction between poly(acryloyl chloride) and pyrenemethanol and subsequent hydrolysis of the unreacted acylchloride groups. This random copolymer consists of hydrophobic pyrene‐containing acrylate units and hydrophilic acrylic acid units, which can self‐assemble into nanoparticles in water. Under UV irradiation, the nanoparticles can be disrupted with decreasing particle number resulted from the photolysis of pyrenylmethyl esters, where the hydrophobic segments are converted to hydrophilic acrylic acids; at low pH, the acrylic acid segments are protonated and collapsed, thus the nanoparticles will be shrunk and aggregated; at high pH, the nanoparticles change to fractal structures owing to the aggregation of partially dissociated nanoparticles and the subsequent structural reorganization of the clusters. The controlled release of Nile Red from the nanoparticles stimulated by photo and pH separately and synergistically is demonstrated. The nanoparticles self‐assembled from the dual‐stimuli‐sensitive polymer can be used as a new nanocarrier and find their applications in delivery system.

image
Poly(methyl vinyl ether‐alt‐maleic acid)‐Functionalized Porous Silicon Nanoparticles for Enhanced Stability and Cellular Internalization
Authors: Shahbazi Mohammad‐Ali , Almeida Patrick V. , Mäkilä Ermei , Correia Alexandra , Ferreira Mónica P. A. , Kaasalainen Martti , Salonen Jarno , Hirvonen Jouni , Santos Hélder A.
Published: February 2014

Currently, developing a stable nanocarrier with high cellular internalization and low toxicity is a key bottleneck in nanomedicine. Here, we have developed a successful method to covalently conjugate poly(methyl vinyl ether‐co‐maleic acid) (PMVE‐MA) copolymer on the surface of (3‐aminopropyl)triethoxysilane‐functionalized thermally carbonized porous silicon nanoparticles (APSTCPSi NPs), forming a surface negatively charged nanovehicle with unique properties. This polymer conjugated NPs could modify surface smoothness, charge, and hydrophilicity of the developed NPs, leading to considerable improvement in the colloidal and plasma stabilities via enhanced suspensibility and charge repulsion. Furthermore, despite the surface negative charge of the polymer‐conjugated NPs, the cellular internalization was increased in both MDA‐MB‐231 and MCF‐7 breast cancer cells. These results provide a proof‐of‐concept evidence that such polymer‐based PSi nanocomposite can be extensively used as a promising candidate for intracellular drug delivery.

image
Airflow‐Field‐Induced Sandwich‐Type Membrane of Block Copolymer for Selective Ion Separation
Authors: Shan Feng , Lu Xuemin , Guan Junfang , Lu Qinghua , Feng Xingliang
Published: February 2014

A simple and effective airflow method to prepare sandwich‐type block copolymer films is reported. The films are composed of three layers: vertically oriented nanocylinders align in both upper and bottom layers and irregular nanocylinders exist in the bulk of the film. The vertically oriented nanocylinders in both sides can provide high accessibility to ions and ensures the exchange of chemical species between the membrane and external environment, while the irregularly oriented nanocylinders in the middle part of the film can prolong the pathway of ions transportation and enhance ions selectivity.

image
Global large solutions to incompressible Navier‐Stokes equations with gravity
Authors: Peng Weimin , Zhou Yi
Published: February 2014

In this per, we consider a special class of initial data for the three‐dimensional incompressible Navier–Stokes equations with gravity. We show that, under such conditions, the incompressible Navier‐Stokes equations with gravity are globally well posed, and the velocity minus gravity term has finite energy. The important features of the initial data is that the velocity fields minus gravity term are almost parallel to the corresponding vorticity fields in a very large space domain. Copyright © 2014 John Wiley & Sons, Ltd.
Severe obesity, heart disease, and death among white, african american, and hispanic postmenopausal women
Authors: McTigue Kathleen M. , Chang Yue‐Fang , Eaton Charles , Garcia Lorena , Johnson Karen C. , Lewis Cora E. , Liu Simin , Mackey Rachel H. , Robinson Jennifer , Rosal Milagros C. , Snetselaar Linda , Valoski Alice , Kuller Lewis H.
Published: February 2014

Objective

To compare mortality, nonfatal coronary heart disease (CHD), and congestive heart failure (CHF) risk across BMI categories in white, African American, and Hispanic women, with a focus on severe obesity (BMI ≥ 40), and examine heterogeneity in weight‐related CHD risk.

Methods

Among 156,775 Women's Health Initiative observational study and clinical trial participants (September 1993‐12 September 2005), multivariable Cox models estimated relative risk for mortality, CHD, and CHF. CHD incidence was calculated by anthropometry, race, and cardiovascular risk factors (CVRF).

Results

Mortality, nonfatal CHD, and CHF incidence generally rose with BMI category. For severe obesity versus normal BMI, hazard ratios (HRs, 95% confidence interval) for mortality were 1.97 (1.77‐2.20) in white, 1.55 (1.20‐2.00) in African American, and 2.59 (1.55‐4.31) in Hispanic women; for CHD, HRs were 2.05 (1.80‐2.35), 2.24 (1.57‐3.19), and 2.95 (1.60‐5.41) respectively; for CHF, HRs were 5.01 (4.33‐5.80), 3.60 (2.30‐5.62), and 6.05 (2.49‐14.69). CVRF variation resulted in substantial variation in CHD rates across BMI categories, even in severe obesity. CHD incidence was similar by race/ethnicity when differences in BMI or CVRF were accounted for.

Conclusions

Severe obesity increases mortality, nonfatal CHD, and CHF risk in women of diverse race/ethnicity. CVRF heterogeneity contributes to variation in CHD incidence even in severe obesity.
Synthesis, characterization, and thermal properties of cyanate esters with azo linkages
Authors: Rakesh Samikannu , Thulasiraman Venu , Sarojadevi Muthusamy
Published: February 2014

A series of azo functionalized diols were synthesized through diazotization which involves the reaction of amine with phenol and 2,6‐dimethyl phenol. Four different amines have been used to prepare five bisphenols. These bisphenols were converted to their corresponding cyanate esters by treatment with cyanogen bromide (BrCN) in the presence of triethylamine (Et3N). The chemical structures of the prepared compounds were characterized with Fourier Transform Infrared, 1H‐NMR, 13C‐NMR spectroscopy, and elemental analysis. Dynamic curing behavior was investigated using differential scanning calorimetry. The maximum curing temperature of these cyanate esters are in the range of (186–208°C). Tg values of the polycyanurate networks are in the range of 245–276°C. The thermal properties of cured cyanate ester were studied at a heating rate of 10°C min−1 in N2 atmosphere. The polymers showed excellent thermal stability (T10 was found to be in the range 405–438°C) and the percentage of char yield at 800°C were found to be 30–49. The flame retardancy of the cyanate ester resins have been studied using limited oxygen index value which is in the range of 29.5–37.1 at 800°C. POLYM. ENG. SCI., 55:47–53, 2015. © 2014 Society of Plastics Engineers
1,3‐butadiene polymerization using Co/Nd‐based Ziegler/Natta catalyst: Microstructures and properties of butadiene rubber
Authors: Chatarsa Chansuree , Prasassarakich Pattarapan , Rempel Garry L. , Hinchiranan Napida
Published: February 2014

Among Ziegler‐Natta catalysts used for 1,3‐butadiene (1,3‐BD) polymerization, the advantage of a neodymium (Nd)‐based catalyst is that it provides butadiene rubber (BR) with a high content of cis−1,4 configuration and a low amount of vinyl−1,2 units. Whereas, a cobalt (Co)‐based catalyst can produce BR with a low content of trans−1,4 configuration. Thus, this research was aimed to prepare BR containing a high content of cis−1,4 configuration with low amounts of both trans−1,4 and vinyl−1,2 units using a combination of Nd‐ and Co‐based Ziegler/Natta catalysts with triethyl aluminum (TEAL) and diethyl aluminum chloride (DEAC) acting as a co‐catalyst and a chlorinating agent, respectively. The effects of the molar Co/Nd ratio, TEAL concentration, DEAC loading, 1,3‐BD content, solvent type, and reaction temperature on % conversion, microstructures, molecular weight, and molecular weight distribution of the obtained BR (Co/Nd‐BR) were evaluated. The Co/Nd‐BR having >97% of cis−1,4 configuration, <2% of trans−1,4 structure, and <1% of vinyl−1,2 unit with >80% conversion was achieved when 3.01 M of 1,3‐BD concentration was treated in a toluene/cyclohexane mixture (7/3 [w/w]). The Co/Nd‐BR exhibited no gel formation with high mechanical performance, which was equivalent to commercial BR produced from a Nd‐based catalyst system. POLYM. ENG. SCI., 55:14–21, 2015. © 2014 Society of Plastics Engineers
An Unusual Case of Flecainide‐induced QT Prolongation Leading to Cardiac Arrest
Authors: Oguayo Kevin N. , Oyetayo Ola O. , Costa Steven M. , Mixon Timothy A.
Published: February 2014

Flecainide is recommended as a first‐line antiarrhythmic drug to maintain normal sinus rhythm in patients with atrial fibrillation (AF) who have structurally normal hearts or hypertension without left ventricular hypertrophy. Flecainide is a sodium channel blocker with minimal effects expected on ventricular repolarization. We describe the case of a 32‐year‐old man with a structurally normal heart and persistent AF who was started on diltiazem and flecainide 50 mg twice/day approximately a year prior to presentation. Due to persistent and bothersome symptoms, his dose was increased to 150 mg twice/day, which was associated with a progressive lengthening of his corrected QT interval. On the day of presentation, he underwent an exercise test as part of his job requirements. While running, he felt lightheaded and experienced a syncopal event and cardiac arrest. An automated external defibrillator was available that displayed polymorphic ventricular tachycardia. The patient was successfully resuscitated. Although rare, this case suggests that flecainide can induce QT prolongation leading to torsades de pointes. Clinicians should be aware and consider periodic evaluations with electrocardiograms.
Trimethylsilyl‐substituted triazole‐based ligand for copper‐mediated single‐electron transfer living radical polymerization of methyl methacrylate
Authors: Sangtrirutnugul Preeyanuch , Wised Kritdikul , Maisopa Purmpoon , Trongsiriwat Nisalak , Tangboriboonrat Pramuan , Reutrakul Vichai
Published: February 2014

The tripodal ‘click’ compound tris(4‐trimethylsilylmethyl‐1,2,3‐triazolylmethyl)amine (TTTA) was prepared and investigated as a ligand for copper‐catalysed single‐electron transfer living radical polymerization of methyl methacrylate (MMA). Bulk polymerizations catalysed by Cu0/CuBr2/TTTA with a molar ratio of [MMA]0/[ethyl‐2‐bromoisobutyrate]0/[CuBr2]0/[TTTA]0 = 200:2:1:1 and a 1.0 × 1.0 cm2 Cu0 sheet were fast and well controlled (76% conversion with Mw/Mn = 1.19 after 3.5 h). Greater amounts of added air generally gave slower polymerizations although Mw/Mn remained low (<1.3) even when the polymerization was carried out under aerobic conditions. Decreasing initial concentrations of the Cu0/CuBr2/TTTA catalyst system or polymerization temperatures also resulted in slower polymerizations and yielded polymers with broader dispersity. Kinetic studies in the temperature range 40–90 °C revealed an apparent activation energy of 22.6 kJ mol−1. © 2014 Society of Chemical Industry
MALDI imaging mass spectrometry profiling of proteins and lipids in clear cell renal cell carcinoma
Authors: Jones Elizabeth Ellen , Powers Thomas W. , Neely Benjamin A. , Cazares Lisa H. , Troyer Dean A. , Parker Alexander S. , Drake Richard R.
Published: February 2014

Reducing the incidence and mortality rates for clear cell renal cell carcinoma (ccRCC) remains a significant clinical challenge with poor 5‐year survival rates. A unique tissue cohort was assembled of matched ccRCC and distal nontumor tissues (n = 20) associated with moderate risk of disease progression, half of these from individuals who progressed to metastatic disease and the other half who remained disease free. These tissues were used for MALDI imaging MS profiling of proteins in the 2–20 kDa range, resulting in a panel of 108 proteins that had potential disease‐specific expression patterns. Protein lysates from the same tissues were analyzed by MS/MS, resulting in identification of 56 proteins of less than 20 kDa molecular weight. The same tissues were also used for global lipid profiling analysis by MALDI‐FT‐ICR MS. From the cumulative protein and lipid expression profile data, a refined panel of 26 proteins and 39 lipid species was identified that could either distinguish tumor from nontumor tissues, or tissues from recurrent disease progressors from nonrecurrent disease individuals. This approach has the potential to not only improve prognostic assessment and enhance postoperative surveillance, but also to inform on the underlying biology of ccRCC progression.
Density functional theory study of methoxide promoted and Zn(II)‐complexed methoxide promoted cleavages of aryl‐ and alkyl acetates in methanol. Transition from concerted to stepwise processes as a function of leaving group ability
Authors: Maxwell Christopher I. , Neverov Alexei A. , Mosey Nicholas J. , Stan Brown R.
Published: February 2014

Density functional theory calculations were performed for the methanolysis reactions of a set of aryloxy and alkoxy acetates (1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h, 1i, 1j, 1k, 1l, 1m) promoted by methoxide and a 1,5,9‐triazacyclododecane‐complexed Zn(II)‐methoxide [2(OCH3)]+ in order to give free energies and structural data for the various intermediates and transition states along the reaction pathway. The methoxide‐promoted reactions experience a transition of pathways from enforced‐concerted addition of CH3O− to the C = O unit for substrates having a good aryloxy leaving groups (LGs) with strong electron withdrawers (1a, 1b, 1c, 1d, 1e) to a two step process with rate‐limiting CH3O‐ attack on aryloxy acetates having higher (the pKa of the parent phenol of the LG in methanol) values. Only in the case of the substrates 1i‐m having alkoxy LGs is there an observed change in rate‐limiting step that occurs at the quasi‐symmetrical point where the . The methanolysis process for the 2,4‐dinitrophenoxy substrate (1a) promoted by [2(OCH3)]+ involves transient binding of the substrate to the metal complex followed by a rate‐limiting, enforced‐concerted attack of Zn(II)‐coordinated –OCH3, with fast breakdown of an addition intermediate that does not have a significant lifetime. For substrates 1b,c having slightly less electron withdrawing substituents, the reaction has two steps with rate‐limiting attack and an unassisted LG departure. As the increases, the reaction still has two steps with rate‐limiting attack, but departure of the LG is now assisted by its coordination to the metal ion. For alkoxy containing substrates, a change in rate‐limiting step occurs centered at methoxy acetate, 1j, (when ) for which the second step of metal ion assisted departure of methoxide becomes partially rate‐limiting. The Brønsted plots computed for the methoxide‐promoted and [2(OCH3)]+‐promoted methanolyses are compared with the previously determined experimental data and are analyzed as arising not from a common line attributable to all substrates but rather in terms of separate, but intersecting, plots for aryl‐ and alkyl acetates. Copyright © 2014 John Wiley & Sons, Ltd.
Improvement in semipermeable membrane performance of wholly aromatic polyamide through an additive processing strategy
Authors: Aiba Motohiro , Tokuyama Takahiro , Baba Susumu , Matsumoto Hidetoshi , Tomioka Hiroki , Higashihara Tomoya , Ueda Mitsuru
Published: February 2014

A new concept for the method to provide semipermeability in ultrathin and single‐component wholly aromatic polyamide membranes has been developed for the first time. It was found that water molecules could permeate through the membrane prepared not from polyamides containing flexible ether, bulky binaphthyl, or fluorene rigid units, but one with carboxylic acid groups under a reverse osmosis mode. However, the enhancement of water transport properties by introducing the hydrophilic group of polyamide was not substantial. Therefore, polyamide membranes were prepared from the solution containing aqueous additives in order to weaken hydrogen bonds between polymer chains and thereby to suppress the aggregation of the polymer chains. As a result, water flux was dramatically improved with slightly improved NaCl rejection. Our analyses based on attenuated total reflectance Fourier transform infrared spectroscopy and solid‐state carbon polarization and magic angle spinning nuclear magnetic resonance (13C CPMAS NMR) spectroscopy confirmed that the aggregation of polymer chains due to the hydrogen bonds among the amide linkages was suppressed by the co‐ordination of the aqueous additives to the amide linkage. The state of water in the membranes analyzed by differential scanning calorimetry also supported the formation of pores. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1275–1281
On the pH‐sensing properties of differently prepared tungsten oxide films
Authors: Drensler Stefanie , Walkner Sarah , Mardare Cezarina Cela , Hassel Achim Walter
Published: February 2014

In this paper, different preparation routes and designs for pH sensing metal/metal oxide electrodes are evaluated. Crystallographic changes in the oxide film are responsible for the pH‐sensing capability of tungsten oxide. As the present oxide structure is directly limiting the measuring range, as‐received tungsten oxide powders were heat treated to produce polymorphs of WO3, in an attempt to extend the measuring range. Furthermore, electrochemical oxide covered electrodes ranging from micro‐ down to nano‐dimensions have been implemented. Optional coating with Nafion, serving as a membrane material, allows shifting the measuring range even to strongly alkaline conditions.