bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermodynamic scaling of the shear viscosity of Mie n-6 fluids and their binary mixtures
Authors: Delage-Santacreu Stephanie , Galliero Guillaume , Hoang Hai , Bazile Jean-Patrick , Boned Christian , Fernandez Josefa
Published: May 2015

In this work, we have evaluated the applicability of the so-called thermodynamic scaling and the isomorph frame to describe the shear viscosity of Mie n-6 fluids of varying repulsive exponents (n = 8, 12, 18, 24, and 36). Furthermore, the effectiveness of the thermodynamic scaling to deal with binary mixtures of Mie n-6 fluids has been explored as well. To generate the viscosity database of these fluids, extensive non-equilibrium molecular dynamics simulations have been performed for various thermodynamic conditions. Then, a systematic approach has been used to determine the gamma exponent value (γ) characteristic of the thermodynamic scaling approach for each system. In addition, the applicability of the isomorph theory with a density dependent gamma has been confirmed in pure fluids. In both pure fluids and mixtures, it has been found that the thermodynamic scaling with a constant gamma is sufficient to correlate the viscosity data on a large range of thermodynamic conditions covering liquid and supercritical states as long as the density is not too high. Interestingly, it has been obtained that, in pure fluids, the value of γ is directly proportional to the repulsive exponent of the Mie potential. Finally, it has been found that the value of γ in mixtures can be deduced from those of the pure component using a simple logarithmic mixing rule.
Towards a predictive route for selection of doping elements for the thermoelectric compound PbTe from first-principles
Authors: Joseph Elad , Amouyal Yaron
Published: May 2015

Striving for improvements of the thermoelectric (TE) properties of the technologically important lead telluride (PbTe) compound, we investigate the influence of different doping elements on the thermal conductivity, Seebeck coefficient, and electrical conductivity applying density functional theory calculations. Our approach combines total-energy calculations yielding lattice vibrational properties with the Boltzmann transport theory to obtain electronic transport properties. We find that doping with elements from the 1st and 3rd columns of the periodic table reduces the sound velocity and, consequently, the lattice thermal conductivity, while 2nd column dopants have no such influence. Furthermore, 1.6 at. % doping with 4th and 5th column elements provides the highest reduction of lattice thermal conductivity. Out of this group, Hf doping results in maximum reduction of the sound velocity from 2030 m s−1 for pure PbTe to 1370 m s−1, which is equivalent to ca. 32% reduction of lattice thermal conductivity. The highest power factor values calculated for 1.6 at. % doping range between 40 and 56 μW cm−1 K−2, and are obtained for substitution with dopants having the same valence as Pb or Te, such as those located at the 2nd, 14th, and 16th columns of the periodic table. We demonstrate how this method may be generalized for dopant-selection-oriented materials design aimed at improving TE performance of other compounds.
Correlation of size, velocity, and autonomous phase of a plasmoid in atmosphere with the dissipated energy
Authors: Fantz U. , Friedl R. , Briefi S.
Published: May 2015

The visual properties of a large plasmoid rising from a water container into the air for up to 450 ms are brought into correlation with the total energy dissipated into the system, and, in particular, with the energy used for plasma generation. The latter parameters are deduced from the time-resolved discharge current and voltage of the capacitor bank which is used as energy supply. By varying the experimental parameters, the energy dissipated to the system varies between 5 kJ and 30 kJ from which 10% to 30% is transferred to the plasma. Clear correlations are obtained for the size of the plasmoid changing from 15 cm to 35 cm in width, the ascent velocity ranging from 1 m/s to 2 m/s, and the rising height for which up to 85 cm is measured. For the relation of the autonomous phase with the energy transferred to the plasma, two trends are observed: 450 ms duration is achieved in maximum with the present setup being almost independent on the electrode gap, the voltage-on time, the water conductivity, or the type of salt dissolved in the water. On the other hand, an almost linear dependence is obtained by changing the capacitance.
Superresolution microscopy reveals chromosomes’ smallest structure
Authors: Miller Johanna L.
Published: May 2015

It’s long been thought that at size scales of tens of nanometers, our genetic material is packaged in a neat, orderly way. New observations show that’s not the case.
Momentum grows for new climate agreement
Authors: Kramer David
Published: May 2015

Pledged US greenhouse gas cuts should need no new authorizations from Congress, officials say.
Is solid helium a supersolid?
Authors: Hallock Robert
Published: May 2015

Recent experiments suggest that helium-4 atoms can flow through an experimental cell filled with solid helium. But that incompletely understood flow is quite different from the reported superfluid-like motion that so excited physicists a decade ago.
Talking science with journalists
Authors: Bardi Jason Socrates , Meyers Catherine
Published: May 2015

The media attention bestowed on scientists is like a hundred-year flood—rare but potentially overwhelming for the unprepared.
Bárcena Volcano, 1952: a 60-year report on the repopulation of San Benedicto Island, Mexico, with a review of the ecological impacts of disastrous events
Authors: Brattstrom Bayard H.
Published: May 2015

Long-term ecological studies are desirable, but rare. I here present data from a 60-year study on the repopulation of San Benedicto Island following a volcano eruption in 1952. Bárcena Volcano appeared on 1 August 1952 on San Benedicto Island, Revillagigedo Islands, Mexico. Within 20 min, the entire island was engulfed in a cloud of ash and pumice, which covered all the plants, killed an estimated 20 000 sea birds within hours and caused the subsequent extinction of an endemic race of rock wren (Salpinctes obsoleta exsul). The results of studies on revegetation and repopulation of the island for the first 10 years after the volcanic eruption were summarised by Brattstrom in 1963. This report extends the studies to 2012. The distribution of the land crab (Aegecarcinus planatus) has increased on the island. By 1971 the crab occurred only over the northern one-eighth of the island, but by 1978 it could be found on one-third of the island. No studies on its distribution have been made since then. Total sea bird populations steadily increased up to 1971 and then rapidly declined, though these changes in numbers are largely due to a fluctuation in the populations of the masked booby (Sula dactylatra). The changes in the booby population may have been due to reproductive and feeding success or to immigration and emigration. The decline in the shearwater (Puffinus ssp.) populations are largely due to erosion and destruction of their burrows; their numbers did not increase until 2000. The formation of a large lava delta created a new habitat, which permitted the establishment of a species of sea bird new to the island, the red-footed booby (Sula sula). Numerous non-resident waifs or stray birds have been observed on the island but most have not become established. The exception is the Laysan albatross (Phoebastria immutabilis), breeding at present in low (3–712) numbers. The original flora consisted of 10 species. The volcano caused four species to become extinct, two re-established themselves, and two species new to the island arrived. There have been marked erosional changes, and the accidental introduction of exotic plants may dramatically alter the vegetation of the island.
Usage-related variation in the referential range ofbluein marketing context
Authors: Anishchanka Alena V. , Speelman Dirk , Geeraerts Dirk
Published: May 2015

The paper explores language-internal variation in the referential meaning of the lexical formblue. Taking a usage-based cognitive approach, we analyze the referential range ofbluein several marketing contexts from a semasiological and an onomasiological perspective. The study develops an interdisciplinary method that combines frequency analysis with mapping of the referent distributions in the three-dimensionalCIELabcolor space. It is argued that the observed referential variation inblueis influenced by usage-related factors such as availability of the referents, diversity of color naming strategies and onomasiological competition between lexical forms in the individual product categories.
Exploring the grammar of perception
Authors: Divjak Dagmar
Published: May 2015

In this paper, I pursue the distributional hypothesis that the meaning of a word is derived from the linguistic contexts in which it occurs and apply it to verbs of perception. Differently from NLP implementations of the distributional hypothesis, I explicitly limit the range of variables to the grammatical domain and chart the way in which verbs of Vision, Hearing and Touch are used, morphologically and syntactically, in a representative sample of corpus data. Some aspects of experience are so central and pervasive that reference to them has grammaticalized (Divjak 2010; see also Janda & Lyashevskaya 2011; Newman 2008). The aim is, firstly, to determine to which extent a verb’s grammatical context alone allows us to classify utterances according to the perception type, and, secondly, to chart the similarities and differences in the verbs’ preference for morphological markers and syntactic constructions. If contexts are highly specialized, language structure, as it is witnessed in use, could assist sensory impaired speakers in building up viable representations of concepts, even if sensory experience is lacking. If, in addition, similarities between certain sensory perception verbs are high, sensory impaired speakers could use these similarities to perform analogical mapping across senses and ground concepts relating to the impaired sense in a cognate sensory experience. The findings are relevant for concept acquisition and representation in general and for concept acquisition and representation in sensory impaired populations, such as the blind, in particular.
Synaesthesia
Authors: Strik Lievers Francesca
Published: May 2015

In the existing literature on synaesthetic metaphors in poetry it is proposed that transfers tend to go from the ‘lower’ (touch, smell, taste) to the ‘higher’ (sight, hearing) sensory modalities. The purpose of this article is to establish if the same directionality also holds for synaesthetic associations found in other text types. To this end, a method for the semi-automatic extraction of synaesthesia is introduced and applied to general-purpose corpora of English (ukWaC) and Italian (itWaC). In the data collected for these languages, most transfers proceed in the expected direction, e.g.sweet voice, but instances of ‘backward’ transfers are also found, e.g.bitter cold. Based on these results, it is claimed that the ‘directionality principle’ reflects thefrequencyof association types, rather than representing universal constraints on synaesthetic transfers, as has often been more or less explicitly assumed. It is here argued that both properties of human perception and more strictly linguistic factors can account for the frequency tendencies observed in synaesthesia. The proposed interpretation is also shown to account for apparently contradictory evidence coming from typological studies on verbs of perception.
Sensation, perception and cognition
Authors: Viberg Åke
Published: May 2015

This paper presents an analysis of the field of perception verbs in Swedish within a typological and contrastive framework. Earlier work has to a great extent focused on the concepts see and hear. This article focuses on the more ‘raw’ form of perception represented by sensations and on the combination of meanings referring to perception and cognition in Swedishkänna‘feel, know’. The polysemy ofkännaturns out to be very language-specific even in relation to the most closely related Germanic languages. The polysemy ofkännais interesting also because this verb can refer to internal (bodily) perception and has an extension that covers blended spaces combining cognitive elements with emotional and bodily feelings (cf.feel remorse,feel convinced). Special attention is paid also to sensory verbs describing sensations of light and sound (cf. Englishglitter,glimmer,rattle,creak, etc.) and of bodily sensations and pain (cf.ache,itch, etc.) Sensations are interesting because — similar to sensory adjectives — evaluation and intensity are central components of their meaning in addition to the fine-grained description of sensory qualia. There are great differences across languages in the degree of elaboration of sensory verbs referring to sensations. Recent typological work has demonstrated great elaborations of taste verbs in some languages, whereas other languages have elaborated odor verbs. Swedish (similar to many other European languages) has a rich repertoire of sound verbs.
Bilingual compound verbs in children’s Panjabi-English codeswitched narratives
Authors: Crutchley Alison Claire
Published: May 2015

Bilingual compound verbs (BCVs) are documented in various languages and are common in codeswitching between English and South Asian languages. It has been suggested that BCVs have no monolingual equivalent, and are generated by a ‘third system’ independent of the two languages. BCVs have also been cited as evidence of language convergence, and as a strategy employed by dominant bilinguals to circumvent lexical gaps in one language. BCVs were common in narratives from four to six-year-old Panjabi-English children in Huddersfield, UK. BCVs are argued to be based on analogy with Panjabi monolingual compound verbs, and to be unrelated to language convergence or language dominance. Instead, BCV use relates to two types of codeswitching in the data: one utilising the simplest structures from both languages, the other drawing more fully on the two languages’ grammatical resources. It is suggested that BCVs enable children with limited overall bilingual competence to ‘do codeswitching’.
Differential object marking in Spanish-English early bilinguals
Authors: Ticio M.Emma
Published: May 2015

This paper examines the emergence and acquisition of marked accusative objects (Differential Object Marking, DOM,Bossong, 1991) in the spontaneous production of seven early Spanish-English simultaneous bilinguals (henceforth, 2L1) with different linguistic environments. The main finding is that the 2L1 group examined did not acquire differentially marked objects in the period studied, up to 3;6, nor did they behave similarly to Spanish monolingual children (L1) acquiring DOM (Montrul, 2011;Rodríguez-Mondoñedo, 2008). The current results support previous claims that link protracted development and incomplete acquisition (Montrul, 2008;Montrul and Sánchez-Walker, 2013). Tentatively, this study concludes that under reduced input conditions, 2L1 develop core aspects of their language, such as accusative and dative structures, but cannot acquire language-specific properties, such as the acquisition of the [person] feature needed for DOM in Spanish.
Issues with the capture-recapture measure of vocabulary size
Authors: Nelson Robert
Published: May 2015

This short paper discusses shortcomings of the capture-recapture (CR) method of estimating vocabulary size (Meara & Olmos Alcoy, 2010; Williams, Segalowitz & Leclair, 2014). When sampling from a population generated by a power-law process (e.g., a Zipf distribution), the probability that any given member is selected is dependent on its rank, such that higher frequency rank (i.e., 1st, 2nd, 3rd) members are much more likely to be selected than lower rank (i.e., 100th, 1000th) members. Because of this, sampling is much more likely to select from the same limited group of words. The CR measure, however, assumes a uniform distribution, and so drastically underestimates the size of the vocabulary when applied to power-law data. Work with simulated data shows ways that the degree of underestimation may be lessened. Applying these methods to real data shows effects parallel to those in the simulations.
Medicinal plant extracts and nematode control.
Authors: Chagas A. C. S.
Published: May 2015

Several aspects should be taken into consideration in relation to the use of active botanical extracts or compounds in parasite control: extraction, conservation, phytochemical study, determination of lethal concentration
in vitro
, toxicity to the host, effective dose
in vivo
, residual period, stability, residues/metabolites generated and costs. The
in vitro
tests that have been used to screen biological activity were developed to detect parasite resistance to anthelmintics. In this way, the effects of a potent plant extract can be underestimated or dismissed if the selected methods disregard some factors that can influence the results, such as solubility or an indirect effect on the nematode. Despite this, the development of strategies that are less dependent on
in vivo
testing is important. There is a need for fuller investigations not restricted only to indicating whether or not a phytotherapy was effective against parasites. The divergence between efficacy
in vitro
and inefficacy
in vivo
can be attributed to key factors related to bioavailability as well as pharmacology of the botanical substances in the host organism. It is important to focus studies to determinate the most appropriate adjuvants and to develop formulation models that can be adapted according to the nature of the plant extract or bioactive compound isolated, to serve as starting points for the development of semi-synthetic and synthetic substances.
Toward high-throughput phenotyping: unbiased automated feature extraction and selection from knowledge sources
Authors: Yu Sheng , Liao Katherine P , Shaw Stanley Y , Gainer Vivian S , Churchill Susanne E , Szolovits Peter , Murphy Shawn N , Kohane Isaac S. , Cai Tianxi
Published: May 2015

Objective Analysis of narrative (text) data from electronic health records (EHRs) can improve population-scale phenotyping for clinical and genetic research. Currently, selection of text features for phenotyping algorithms is slow and laborious, requiring extensive and iterative involvement by domain experts. This paper introduces a method to develop phenotyping algorithms in an unbiased manner by automatically extracting and selecting informative features, which can be comparable to expert-curated ones in classification accuracy.

Materials and methods Comprehensive medical concepts were collected from publicly available knowledge sources in an automated, unbiased fashion. Natural language processing (NLP) revealed the occurrence patterns of these concepts in EHR narrative notes, which enabled selection of informative features for phenotype classification. When combined with additional codified features, a penalized logistic regression model was trained to classify the target phenotype.

Results The authors applied our method to develop algorithms to identify patients with rheumatoid arthritis and coronary artery disease cases among those with rheumatoid arthritis from a large multi-institutional EHR. The area under the receiver operating characteristic curves (AUC) for classifying RA and CAD using models trained with automated features were 0.951 and 0.929, respectively, compared to the AUCs of 0.938 and 0.929 by models trained with expert-curated features.

Discussion Models trained with NLP text features selected through an unbiased, automated procedure achieved comparable or slightly higher accuracy than those trained with expert-curated features. The majority of the selected model features were interpretable.

Conclusion The proposed automated feature extraction method, generating highly accurate phenotyping algorithms with improved efficiency, is a significant step toward high-throughput phenotyping.
The Effect of Body Mass Index on Postoperative Morbidity After Orthopaedic Surgery in Children With Cerebral Palsy
Authors: Minhas Shobhit V. , Chow Ian , Otsuka Norman Y.
Published: May 2015

Background:

Although a plethora of literature exists on the impact of body mass index (BMI) in orthopaedic surgery, few have examined its implications in the pediatric cerebral palsy (CP) population. The aim of this study is to evaluate the effect of BMI class on 30-day complications after orthopaedic surgery on children with CP.

Methods:

A retrospective analysis of the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) Pediatric participant use files from 2012 to 2013 was conducted. Patients with a diagnosis of CP undergoing any orthopaedic procedure were included and subclassified according to BMI classes: underweight, normal weight, overweight, and obese. Multivariate logistic regressions were performed to evaluate the independent effect of BMI class on total, surgical site, and medical complications as well as unplanned reoperations.

Results:

A total of 1746 patients were included in our study. These included 345 (19.8%) underweight, 952 (54.5%) normal weight, 209 (12.8%) overweight, and 240 (13.7%) obese children and adolescents. In hip and lower extremity osteotomies, underweight class was an independent risk factor for total complications (P=0.037) and medical complications (P=0.031). Similarly, underweight class was a risk factor for total complications (P=0.022) and medical complications (P=0.019) in spine procedures. Weight class was not independently associated with complications in tendon procedures. Overweight and obesity classes were not associated with any independent increased risk for complications.

Conclusions:

With respect to the pediatric CP population, underweight status was deemed an independent predictor of increased complications in osteotomies and spine surgery with no independent increased risk in the overweight or obese cohorts. This information can greatly aid providers with risk stratification, preoperative counseling, and postoperative monitoring as it relates to orthopaedic surgery.

Level of Evidence:

Level III—Prognostic.
Variation in 60-day Readmission for Surgical-site Infections (SSIs) and Reoperation Following Spinal Fusion Operations for Neuromuscular Scoliosis
Authors: McLeod Lisa , Flynn John , Erickson Mark , Miller Nancy , Keren Ron , Dormans John
Published: May 2015

Background:

Readmission for surgical-site infection (SSIs) following spinal fusion for NMS impacts costs, patient risk, and family burden; however, it may be preventable. The purpose of this study was to examine variation in hospital performance based on risk-standardized 60-day readmission rates for SSI and reoperation across 39 US Children’s Hospitals.

Methods:

Retrospective cohort study using the Pediatric Health Information Systems (PHIS) database involving children aged 10 to 18 years with ICD9 codes indicating spinal fusion, scoliosis, and neuromuscular disease discharged from 39 US children’s hospitals between January 1, 2007 and September 1, 2012. Readmissions within 60 days for SSI were identified based on the presence of ICD9 codes for (1) infectious complication of device or procedure, or (2) sepsis or specific bacterial infection with an accompanying reoperation. Logistic regression models accounting for patient-level risk factors for SSI were used to estimate expected (patient-level risk across all hospitals) and predicted (weighted average of hospital-specific and all-hospital estimates) outcomes. Relative performance was determined using the hospital-specific predicted versus expected (pe) ratios.

Results:

Average volume across hospitals ranged from 2 to 23 fusions/quarter and was not associated with readmissions. Of the 7560 children in the cohort, 534 (7%) were readmitted for reoperation and 451 (6%) were readmitted for SSI within 60 days of discharge. Reoperations were associated with an SSI in 70% of cases. Across hospitals, SSI and reoperation rates ranged from 1% to 11% and 1% to 12%, respectively. After adjusting for age, sex, insurance, presence of a gastric tube, ventriculoperitoneal shunt, tracheostomy, prior admissions, number of chronic conditions, procedure type (anterior/posterior), and level (>9 or <9 vertebrae), pe ratios indicating hospital performance varied by 2-fold for each outcome.

Conclusions:

After standardizing outcomes using patient-level factors and relative case mix, several hospitals in this cohort were more successful at preventing readmissions for SSIs and reoperations. Closer examination of the organization and implementation of strategies for SSI prevention at high-performing centers may offer valuable clues for improving care at lower performing institutions.

Level of Evidence:

Level III.
Correction of Brachymetatarsia and Medial Angulation of the Great Toe of Apert Foot By Distraction Osteogenesis: A Review of 7 Years of Experience
Authors: Calis Mert , Oznur Ali , Ekin Omer , Vargel Ibrahim
Published: May 2015

Background:

Apert foot anomalies may cause severe problems such as pain and development of callus formation related to weight redistribution, problems with footwear, and gait disturbances that may limit their daily activities. The main purpose of this study was to review our experience with distraction osteogenesis for the correction of brachymetatarsia and the great toe angulation of the patients with Apert syndrome.

Methods:

This study retrospectively reviewed 7 patients (14 extremities) followed up for Apert syndrome who underwent distraction for the correction of bilateral congenital brachymetatarsia and angulation of the great toe between 2004 and 2008. Correction of the metatarsal inclination angle, the medial angulation of the great toe, the percentage of lengthening, and lengthening rates of distracted bones were evaluated.

Results:

Patients ranged in age from 4 to 8 years at the distraction operation, with a mean age of 5.4±1.3 years, and the average length of follow-up was 86.6±21.0 months. The length of the first metatarsal bone increased significantly from the average length of 32.6±5.7 mm to an average of 46.7±6.5 mm (P<0.001). The mean lengthening rate and lengthening percentages of distracted bones were 0.4%±0.1%/month and 30.2%±6.4%/month, respectively. Preoperative and postoperative metatarsal inclination angles were at a mean of 43.8±5.12 and 32.6±3.8, respectively, and the correction of metatarsal inclination was considered as statistically significant (P<0.001). The mean angulation of the great toe reduced significantly from 49.8±11.76 to 13.2±8.5 degrees after distraction (P<0.001). Minor complications such as pin loosening, pin-tract infection, and early union that required reoperation were observed in 5 extremities (35.7%).

Conclusions:

Anatomic features of Apert foot may lead to complaints that may limit patients’ daily activities and require as much attention as associated hand and craniofacial anomalies. Distraction appears to be an effective and safe approach for the simultaneous correction of the shortness of the first ray and medial angulation of the great toe.

Level of Evidence:

Level IV.
Traumatic, Posterior Pediatric Hip Dislocations With Associated Posterior Labrum Osteochondral Avulsion: Recognizing the Acetabular “Fleck” Sign
Authors: Blanchard Christopher , Kushare Indranil , Boyles Aaron , Mundy Andrew , Beebe Allan C. , Klingele Kevin E.
Published: May 2015

Background:

Traumatic dislocation of the hip is uncommon in the pediatric population. Concentric reduction is usually achieved by closed means. Open reduction may be needed if there is femoral head fracture, incarcerated fragment, or incomplete reduction due to soft tissue entrapment. We present a series of 10 patients who sustained a posterior hip dislocation or subluxation with associated osteochondral avulsion of the posterior labrum. During surgery they were noted to have a labral injury pattern not previously recognized. Such treatment was dictated by postreduction advanced imaging, which revealed a consistent acetabular “fleck” sign indicative of this labral injury, which has not been previously described in literature.

Methods:

We performed a retrospective case review of patients with traumatic posterior hip dislocation/subluxation, treated operatively for a suspected associated labral tear and fractures.

Results:

Ten patients (2 girls and 8 boys) were identified. Average age was 12.7 years. Eight patients had postreduction computed tomography scans, which revealed a posterior acetabular wall “fleck” sign, suggestive of osteochondral injury. The small bony fragment was consistently displaced at least 2 to 3 mm in all patients with majority of the posterior wall remaining intact. Closed reduction was felt to be congruent in 7 of the 10 patients. All patients were treated operatively for exploration and stabilization of the suspected posterior labrum pathology and associated injuries using a surgical hip dislocation. A consistent pattern of labral pathology was seen in all patients, with disruption of the posterior labrum from the superior 12 o’clock attachment to detachment at the inferior 6 o’clock location. Reattachment of the osteochondral labral avulsion was performed with suture anchors along the posterior rim, and the associated femoral head fractures were also addressed with internal fixation. Two patients had inadequate follow-up and were excluded, the average follow-up for the remaining 8 patients was 9.8 months (range, 6 to 26 mo). There were no findings of avascular necrosis in any of the 8 patients.

Conclusions:

Posterior hip dislocation in children may produce an acetabular “fleck” sign on advanced imaging, which in a stable, concentrically reduced hip has been treated without surgery in the past. Acetabular fleck sign may represent a near-complete avulsion of the posterior labrum as seen in our series. We recommend a high suspicion for this type of labral pathology and surgical repair when acetabular “fleck” sign is identified with hip subluxation or dislocation. Traumatic, posterior hip dislocations in young patients may be associated with significant labral pathology. Acetabular “fleck” sign on advanced imaging may predict such pathology.

Level of Evidence:

IV, retrospective study.
Bent Telescopic Rods in Patients With Osteogenesis Imperfecta
Authors: Lee R. Jay , Paloski Michael D. , Sponseller Paul D. , Leet Arabella I.
Published: May 2015

Background:

Telescopic rods require alignment of 2 rods to enable lengthening. A telescopic rod converts functionally into a solid rod if either rod bends, preventing proper engagement. Our goal was to characterize implant bending as a mode of failure of telescopic rods used in the treatment of osteogenesis imperfecta in children.

Methods:

We conducted a retrospective review of our osteogenesis imperfecta database for patients treated with intramedullary telescopic rods at our institution from 1992 through 2010 and identified 12 patients with bent rods. The 6 boys and 6 girls had an average age at the time of initial surgery of 3.1 years (range, 1.8 to 8.3 y) and a total of 51 telescoping rods. Clinic notes, operative reports, and radiographs were reviewed. The rods were analyzed for amount of lengthening, characteristics of bending, presence of cut out, or disengagement from an anchor point. Bends in the rods were characterized by their location on the implant component. The bent and straight rods were compared. Data were analyzed with the Mann-Whitney test (statistical significance set at P≤0.05).

Results:

Of the 51 telescoping rods, 17 constructs (33%) bent. The average interval between surgery and rod bending was 4.0 years (range, 0.9 to 8.2 y). Before bending, 11 of 17 telescoping rods had routine follow-up radiographs for review. In 10 of the rods, bending was present when early signs of rod failure were first detected. Rod bending did not seem to be related to rod size. There was no area on the rod itself that seemed more susceptible to bending.

Conclusions:

Rod bending can be an early sign of impending rod failure. When rod bending is first noted, it may predispose the rod to other subsequent failures such as loss of proximal and distal fixation and cut out. Rod bending should be viewed as an indicator for closer monitoring of the patient and discussions regarding future need for rod exchange.

Level of Evidence:

Level III—retrospective review.
Transcutaneous Electrical Nerve Stimulation Improves Walking Performance in Patients With Intermittent Claudication
Authors: Seenan Chris , McSwiggan Steve , Roche Patricia A. , Tan Chee-Wee , Mercer Tom , Belch Jill J. F.
Published: May 2015

The purpose of this study was to investigate the effects of 2 types of transcutaneous electrical nerve stimulation (TENS) on walking distance and measures of pain in patients with peripheral arterial disease (PAD) and intermittent claudication (IC). In a phase 2a study, 40 participants with PAD and IC completed a graded treadmill test on 2 separate testing occasions. Active TENS was applied to the lower limb on the first occasion; and placebo TENS, on the second. The participants were divided into 2 experimental groups. One group received high-frequency TENS; and the other, low-frequency TENS. Measures taken were initial claudication distance, functional claudication distance, and absolute claudication distance. The McGill Pain Questionnaire (MPQ) vocabulary was completed at the end of the intervention, and the MPQ–Pain Rating Index score was calculated. Four participants were excluded from the final analysis because of noncompletion of the experimental procedure. Median walking distance increased with high-frequency TENS for all measures (P < .05, Wilcoxon signed rank test, all measures). Only absolute claudication distance increased significantly with low-frequency TENS compared with placebo (median, 179–228; W
s = 39; z = 2.025; P = .043; r = 0.48). No difference was observed between reported median MPQ–Pain Rating Index scores: 21.5 with placebo TENS and 21.5 with active TENS (P = .41). Transcutaneous electrical nerve stimulation applied to the lower limb of the patients with PAD and IC was associated with increased walking distance on a treadmill but not with any reduction in pain. Transcutaneous electrical nerve stimulation may be a useful adjunctive intervention to help increase walking performance in patients with IC.
The Effectiveness of Medication Adherence Interventions Among Patients With Coronary Artery Disease
Authors: Chase Jo-Ana D. , Bogener Jennifer L. , Ruppar Todd M. , Conn Vicki S.
Published: May 2015

Background:

Despite the known benefits of medication therapy for secondary prevention of coronary artery disease (CAD), many patients do not adhere to prescribed medication regimens. Medication nonadherence is associated with poor health outcomes and higher healthcare cost.

Objective:

The purpose of this meta-analysis was to determine the overall effectiveness of interventions designed to improve medication adherence (MA) among adults with CAD. In addition, sample, study design, and intervention characteristics were explored as potential moderators to intervention effectiveness.

Methods:

Comprehensive search strategies helped in facilitating the identification of 2-group, treatment-versus-control–design studies testing MA interventions among patients with CAD. Data were independently extracted by 2 trained research specialists. Standardized mean difference effect sizes were calculated for eligible primary studies, adjusted for bias, and then synthesized under a random-effects model. Homogeneity of variance was explored using a conventional heterogeneity statistic. Exploratory moderator analyses were conducted using meta-analytic analogs for analysis of variance and regression for dichotomous and continuous moderators, respectively.

Results:

Twenty-four primary studies were included in this meta-analysis. The overall effect size of MA interventions, calculated from 18,839 participants, was 0.229 (P < .001). The most effective interventions used nurses as interventionists, initiated interventions in the inpatient setting, and informed providers of patients’ MA behaviors. Medication adherence interventions tested among older patients were more effective than those among younger patients. The interventions were equally effective regardless of number of intervention sessions, targeting MA behavior alone or with other behaviors, and the use of written instructions only.

Conclusions:

Interventions to increase MA among patients with CAD were modestly effective. Nurses can be instrumental in improving MA among these patients. Future research is needed to investigate nurse-delivered MA interventions across varied clinical settings. In addition, more research testing MA interventions among younger populations and more racially diverse groups is needed.
Anger Traits Associated With Cardiovascular Risk Biomarkers in the Metabolic Syndrome
Authors: Lemche Alexandra V. , Chaban Oleg S. , Lemche Erwin
Published: May 2015

Background:

Recent studies have shown that different personality traits contribute to mortality in different subtypes of cardiovascular disease (CVD). Anger traits have been shown to promote the constellation of the metabolic syndrome (MetS), which in turn increases CVD risks.

Objective:

To determine covariation of anger traits with CVD biomarkers, we examined patients (N = 101; 34 men and 67 women; age, 45.6 ± 13.96 years) in a nationally sampled treatment cohort for MetS in the Ukrainian governmental healthcare system.

Methods:

Data collection was conducted in 2007. Laboratory data of single components of the MetS according to International Diabetes Federation Consensus were dependent measures in regression models with self-reported overt aggressivity and covert hostility in the Buss-Durkee Hostility Inventory and sociodemographic data. Structural equation models (SEMs) were tested.

Results:

The SEM results are in favor of a sex-adjusted 2-factor solution R
2 = 0.723), as indicated by equation-level Bentler-Raykov goodness-of-fit coefficients of 0.81 to 0.97 for paths to biological variables. Two latent components, 1 relating to aggressivity and the other to hostility, combine lipid/obesity-related measures and cholesterol-related measures, respectively.

Conclusions:

The SEM results suggest that CVD-risk biomarker variables in this MetS sample (a) associate into 2 distinct profiles and (b) that 1 profile associates with overt anger, whereas the other associates with covert hostility. These results could contribute to more personalized prevention and care in CVD patients.
Cardiovascular Risk in Midlife African American Women Participating in a Lifestyle Physical Activity Program
Authors: Braun Lynne T. , Wilbur JoEllen , Buchholz Susan W. , Schoeny Michael E. , Miller Arlene M. , Fogg Louis , Volgman Annabelle S. , McDevitt Judith
Published: May 2015

Background:

Cardiovascular disease (CVD) is the largest contributor to disparate morbidity and mortality in African American women.

Objective:

The aims of this article are to describe in a cohort of sedentary, urban community-based midlife African American women eligible for a physical activity program their (1) CVD risk factors and (2) awareness, treatment, and control of hypertension and hypercholesterolemia.

Methods:

Cross-sectional baseline findings on 297 women were examined at baseline of a controlled physical activity clinical trial. Cardiovascular disease risks included hypertension, hypercholesterolemia, smoking, diabetes, and obesity. Among women with hypertension and hypercholesterolemia, rates of awareness, treatment, and control were calculated.

Results:

Our sample had significantly more hypertension and obesity than reported in other national samples of African American women. The women mirrored national samples of African American women: fewer than 60% had adequate control of hypertension. Versus national samples of African Americans (men/women combined), our study groups both showed significantly lower low-density-lipoprotein cholesterol level: treatment, 33% versus 63.8%, and control, 24.8% versus 45.3%.

Conclusions:

Because national samples are more heterogeneous, our sample provides important information about CVD risks in inactive, urban community-dwelling, midlife African American women. Given the opportunity, many such women at elevated risk for CVD are willing to participate in a physical activity intervention. They must be identified and offered pharmacological and lifestyle interventions.
Ipilimumab-Induced Granulomatous Disease Occurring Simultaneously With Disease Progression in a Patient With Metastatic Melanoma
Authors: Toumeh Anis , Sakhi Ramen , Shah Sarthi , Arudra Sri Krishna Chaitanya , De Las Casas Luis E. , Skeel Roland T.
Published: May 2015

Malignant melanoma is the most aggressive cutaneous malignancy with dismal prognosis in the advanced setting. The food and drug administration approval of ipilimumab, the monoclonal antibody against cytotoxic T-lymphocyte antigen 4, has significantly changed treatment strategies for this disease. However, the spectrum of immune-related adverse events secondary to ipilimumab therapy is a growing area of research, and clinical observations of rare immune events as a result of such therapies continue to be reported since the approval. The co-occurrence of disease progression along with an immune-related adverse event is extremely rare. We here present the first case, to our knowledge, of diffuse nonnecrotizing granulomatous lymphadenopathy occurring simultaneously with disease progression in a patient with metastatic melanoma after receiving the second dose of ipilimumab.
GO-PCA: An Unsupervised Method to Explore Biological Heterogeneity Based on Gene Expression and Prior Knowledge
Authors: Wagner Florian
Published: May 2015

Genome-wide expression profiling is a cost-efficient and widely used method to characterize heterogeneous populations of cells, tissues, biopsies, or other biological specimen. The exploratory analysis of such datasets typically relies on generic unsupervised methods, e.g. principal component analysis or hierarchical clustering. However, generic methods fail to exploit the significant amount of knowledge that exists about the molecular functions of genes. Here, I introduce GO-PCA, an unsupervised method that incorporates prior knowledge about gene functions in the form of gene ontology (GO) annotations. GO-PCA aims to discover and represent biological heterogeneity along all major axes of variation in a given dataset, while suppressing heterogeneity due to technical biases. To this end, GO-PCA combines principal component analysis (PCA) with nonparametric GO enrichment analysis, and uses the results to generate expression signatures based on small sets of functionally related genes. I first applied GO-PCA to expression data from diverse lineages of the human hematopoietic system, and obtained a small set of signatures that captured known cell characteristics for most lineages. I then applied the method to expression profiles of glioblastoma (GBM) tumor biopsies, and obtained signatures that were strongly associated with multiple previously described GBM subtypes. Surprisingly, GO-PCA discovered a cell cycle-related signature that exhibited significant differences between the Proneural and the prognostically favorable GBM CpG Island Methylator (G-CIMP) subtypes, suggesting that the G-CIMP subtype is characterized in part by lower mitotic activity. Previous expression-based classifications have failed to separate these subtypes, demonstrating that GO-PCA can detect heterogeneity that is missed by other methods. My results show that GO-PCA is a powerful and versatile expression-based method that facilitates exploration of large-scale expression data, without requiring additional types of experimental data. The low-dimensional representation generated by GO-PCA lends itself to interpretation, hypothesis generation, and further analysis.
Controlling False Positive Rates in Methods for Differential Gene Expression Analysis using RNA-Seq Data
Authors: Rocke David M , Ruan Luyao , Gossett J. Jared , Durbin-Johnson Blythe , Aviran Sharon
Published: May 2015

We review existing methods for the analysis of RNA-Seq data and place them in a common framework of a sequence of tasks that are usually part of the process. We show that many existing methods produce large numbers of false positives in cases where the null hypothesis is true by construction and where actual data from RNA-Seq studies are used, as opposed to simulations that make specific assumptions about the nature of the data. We show that some of those mathematical assumptions about the data likely are one of the causes of the false positives, and define a general structure that is not apparently subject to these problems. The best performance was shown by limma-voom and by some simple methods composed of easily understandable steps.
Mass spectrometry-based quantitation of Her2 in gastroesophageal tumor tissue: Comparison to IHC and FISH
Authors: Catenacci Daniel V.T. , Liao Wei-Li , Zhao Lei , Whitcomb Emma , Henderson Les , O’Day Emily , Xu Peng , Thyparambil Sheeno , Krisman David , Bengali Kathleen , Uzzell Jamar , Darflur Marlene , Cecchi Fabiola , Blackler Adele , Bang Yung-Jue , Hart John , Xiao Shu-Yuan , Lee Sang Mee , Burrows Jon , Hembrough Todd
Published: May 2015

Background

Trastuzumab showed survival benefit for Her2-positive gastroesophageal cancers (GEC). Immunohistochemistry (IHC) and fluorescencein situhybridization (FISH) currently determine eligibility for trastuzumab-based therapy. However, both assays are low throughput with various limitations.

Methods

We developed a selected reaction monitoring mass spectrometric (SRM-MS) assay and quantified levels (amol/ug) of Her2-SRM in cell lines (n=27) and GEC tissues (n=139). We compared Her2-SRM expression with IHC/FISH, seeking to determine optimal SRM expression cut-offs to identifyHER2amplification.

Results

After demonstrating assay development, precision, and stability, Her2-SRM measurement was observed to be highly concordant withHER2/CEP17ratio, particularly in a multivariate regression model adjusted for SRM-expression of Met, Egfr, Her3, and HER2-heterogeneity covariates, and their interactions (cell lines r2=0.9842; FFPE r2=0.7643). In GEC tissues, Her2-SRM was detected in 71.2% of cases, and 12.3% were identified as ‘HER2+’. ROC curves demonstrated HER2-SRM levels to have high specificity (100%) at an upper-level cut-off of>750 amol/μg and sensitivity (75%) at lower-level cut-off of <450 amol/ug. We observed an ‘equivocal-zone’ between 450-750 amol/ug, analogous to ‘IHC2+’, but less frequent (9-16% of cases versus 36-41%).

Significance

Compared to IHC, SRM-MS provided more objective and quantitative Her2 expression with excellentHER2/CEP17FISH correlation and fewer ‘equivocal’ cases. Along with the multiplex capability for other relevant oncoproteins, these results demonstrated a refined HER2 expression assay for clinical application.