bluuebunny/crossref_metadata_2025 huggingface dataset:
Chondroitin sulfate and sulfated hyaluronan‐containing collagen coatings of titanium implants influence peri‐implant bone formation in a minipig model
Authors: Korn P. , Schulz M. C. , Hintze V. , Range U. , Mai R. , Eckelt U. , Schnabelrauch M. , Möller S. , Becher J. , Scharnweber D. , Stadlinger B.
Published: August 2013

An improved osseous integration of dental implants in patients with lower bone quality is of particular interest. The aim of this study was to evaluate the effect of artificial extracellular matrix implant coatings on early bone formation. The coatings contained collagen (coll) in conjunction with either chondroitin sulfate (CS) or sulfated hyaluronan (sHya). Thirty‐six screw‐type, grit‐blasted, and acid‐etched titanium implants were inserted in the mandible of 6 minipigs. Three surface states were tested: (1) uncoated control (2) coll/CS (3) coll/sHya. After healing periods of 4 and 8 weeks, bone implant contact (BIC), bone volume density (BVD) as well as osteoid related parameters were measured. After 4 weeks, control implants showed a BIC of 44% which was comparable to coll/CS coated implants (48%) and significantly higher compared to coll/sHya coatings (37%, p = 0.012). This difference leveled out after 8 weeks. No significant differences could be detected for BVD values after 4 weeks and all surfaces showed reduced BVD values after 8 weeks. However, at that time, BVD around both, coll/CS (30%, p = 0.029), and coll/sHya (32%, p = 0.015), coatings was significantly higher compared to controls (22%). The osteoid implant contact (OIC) showed no significant differences after 4 weeks. After 8 weeks OIC for controls was comparable to coll/CS, the latter being significantly higher compared to coll/sHya (0.9% vs. 0.4%, p = 0.012). There were no significant differences in osteoid volume density. In summary, implant surface coatings by the chosen organic components of the extracellular matrix showed a certain potential to influence osseointegration in vivo. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 2334–2344, 2014.
Grade as a prognostic factor in oral squamous cell carcinoma: A population‐based analysis of the data
Authors: Thomas Brian , Stedman Margaret , Davies Louise
Published: August 2013

Objectives/Hypothesis

Historically, histologic grade has not been considered a useful prognostic factor in head and neck squamous cell carcinoma (SCC). However, in other solid tumors, grade is known to affect prognosis. We test the hypothesis that histologic grade is an independent predictor of prognosis in oral cavity SCC.

Study Design

Population‐based cohort study using the Surveillance, Epidemiology, and End Results (SEER) database of the National Cancer Institute.

Methods

Fifteen year cause‐specific survival. Multivariate analysis was performed on a subset of patients diagnosed between 2004 and 2008.

Results

Among patients 20 to 65 years of age with American Joint Committee on Cancer (AJCC) stage I or II cancer, the adjusted risk of death is 2.7 times greater (95% CI 1.72–4.11) if the tumor is poorly differentiated or undifferentiated than it is if the tumor is well differentiated. Among patients 66 to 94 years of age, the risk of death is 3.0 (95% CI 2.02–4.54) times greater. For those over age 65, moderately differentiated tumors also confer an estimated 42% increased risk of death, but this estimate is only borderline significant (P = 0.05).

Conclusions

There is a strong association between histologic grade and survival in patients with AJCC stage I or II oral cavity SCC. High histologic grade in early stage oral cavity cancer is associated with poorer survival and carries independent prognostic value in addition to tumor size, node status, and presence of distant metastasis (TNM) stage. Thus, histologic grade should be considered clinically when making treatment decisions, and multivariable models of survival should include grade as a covariate to improve prognostic accuracy.

Level of Evidence

2b Laryngoscope, 124:688–694, 2014
The effect of transoral robotic surgery on short‐term outcomes and cost of care after oropharyngeal cancer surgery
Authors: Richmon Jeremy D. , Quon Harry , Gourin Christine G.
Published: August 2013

Objectives/Hypothesis

Transoral surgery is an increasingly frequent treatment modality for tumors of the upper aerodigestive tract. This is in large part related to the introduction of transoral robotic surgery (TORS) for oropharyngeal cancer resection, which has demonstrated excellent oncologic and functional outcomes. There is limited data, however, on how TORS compares to traditional open surgery in overall costs and length of hospitalization. With increasing pressure to contain and reduce the costs of medical care, we sought to evaluate the impact of TORS on a national sample of patients undergoing surgery for oropharyngeal cancer.

Study Design

Retrospective cross‐sectional study.

Methods

A cross‐sectional analysis of 9,601 patients who underwent an extirpative procedure for a malignant oropharyngeal neoplasm in 2008 to 2009 was performed using discharge data from the Nationwide Inpatient Sample.

Results

TORS was performed in 116 (1.2%) of cases. TORS patients had a lower rate of gastrostomy tube placement (0% vs. 19%), tracheotomy tube placement (0% vs. 36%), and nonroutine discharge (0% vs. 44%) compared to patients undergoing non‐TORS procedures. After controlling for all other variables, including comorbidity, extent of surgery, and teaching hospital status, TORS was associated with significantly decreased length of hospitalization (mean, −1.5 days) and hospital‐related costs (mean, −$4,285).

Conclusions

TORS is becoming an increasingly frequent technique to treat tumors of the upper aerodigestive tract. These data demonstrate that TORS is associated with a decreased length of hospitalization and hospital‐related costs compared to other surgical techniques.

Level of Evidence

2c. Laryngoscope, 124:165–171, 2014
Cisplatin otoprotection using transtympanic L‐N‐acetylcysteine: A pilot randomized study in head and neck cancer patients
Authors: Yoo John , Hamilton Scott J. , Angel Douglas , Fung Kevin , Franklin Jason , Parnes Lorne S. , Lewis Denise , Venkatesan Varagur , Winquist Eric
Published: August 2013

Objectives/Hypothesis

To evaluate the feasibility and efficacy of transtympanic L‐N‐Acetylcysteine (L‐NAC) administration in patients receiving cisplatin chemotherapy for head and neck cancer.

Study Design

Prospective randomized nonblinded open‐label clinical trial.

Methods

Transtympanic 2% L‐NAC was administered to one randomly selected ear with the other ear as control in each patient. Primary outcome parameter was the difference in the loss of pure tone averages (PTA) at 2, 4, and 8 kHz between the L‐NAC and control ear at 1 to 2 months following chemotherapy.

Results

Eleven patients completed the study, with two patients demonstrating significantly better hearing in the L‐NAC treated ear (18.2%). However, for the overall group, the difference in hearing preservation did not reach significance. Two percent L‐NAC administration was well tolerated in this patient population. There were no adverse effects associated with L‐NAC.

Conclusion

Although the study did not demonstrate a significant benefit overall, transtympanic L‐NAC was associated with significantly better hearing in two patients. Better delivery methods may improve the efficacy of this treatment. L‐NAC remains a promising drug in preventing cisplatin‐induced ototoxicity.

Level of Evidence

1b. Laryngoscope, 124:E87–E94, 2014
Propagation Kinetics of the Radical Polymerization of Methylated Acrylamides in Aqueous Solution
Authors: Schrooten Jens , Lacík Igor , Stach Marek , Hesse Pascal , Buback Michael
Published: August 2013

Propagation rate coefficients, kp, of the radical polymerization of N,N‐dimethylacrylamide (N,N‐dimethylprop‐2‐enamide), N‐methylmethacrylamide (N,2‐dimethylprop‐2‐enamide), and methacrylamide (2‐methylprop‐2‐enamide) in aqueous solution are measured via pulsed‐laser polymerization in conjunction with size‐exclusion chromatography within wide ranges of monomer concentration, temperature, and pressure. As observed for aqueous solutions of other monomers, kp decreases significantly towards higher monomer concentration. For methacrylamide, a higher activation energy and a larger volume of activation are found as compared with N,N‐dimethylacrylamide. These two activation parameters are almost identical for N‐methylmethacrylamide and for N,N‐dimethylacrylamide.

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Soil temperature trends in Büyük Menderes Basin, Turkey
Authors: Yeşilırmak Ercan
Published: August 2013

Soil temperature change is reported to be an important indicator of climate change, as soil temperature integrates all processes occurring at and above the soil surface. Analysis of long‐term trends in soil temperatures and their relationship to climatic variables could provide valuable information on climate change. In this study, soil temperature trends were analysed on seasonal and annual scales at depths of 5, 10, 20, 50 and 100 cm over the period from the 1970s to 2006 at eight sites in the Büyük Menderes Basin in Western Turkey. Also, air temperature, rainfall and sunshine duration records were analysed for trends, and for their correlations with soil temperatures. The results showed a general increase in soil temperatures at all depths and in all seasons. The most significant warmings were observed in summer, especially in the upper layers (5, 10 and 20 cm). The trend magnitudes ranged from −0.91 to 2.05 °C decade−1, depending on site, season and depth. It was observed that air temperature had a clear and dominant influence on soil temperature change. Soil temperatures were also affected by sunshine duration and rainfall. These findings are expected to contribute to our understanding of the linkage between soil temperature change and global warming.
A systematic approach to emergent breast free flap takeback: Clinical outcomes, algorithm, and review of the literature
Authors: Khansa Ibrahim , Chao Albert H. , Taghizadeh Maakan , Nagel Theodore , Wang Duane , Tiwari Pankaj
Published: August 2013

Background

Few evidence‐based and detailed algorithms exist on the management of failing breast free flaps, including use of the numerous salvage tools that are available. The purpose of this study was to analyze our outcomes with an algorithmic approach to breast free flap salvage after vascular compromise. A review of the literature is also presented.

Methods

A retrospective review of all breast free flaps performed at our institution between 2007 and 2012 was performed. Flaps with intraoperative and postoperative vascular complications were analyzed.

Results

A total of 612 microsurgical breast reconstructions in 442 patients were reviewed. Of these, 72 (11.8%) flaps had intraoperative vascular complications, and 36 (5.9%) had postoperative vascular complications. The total flap loss rate was 2.8%. The most commonly used salvage modalities were anastomotic revision (72%), heparin irrigation (72%), systemic heparin (37%), Fogarty catheter thrombectomy (17.6%), thrombolytics (13%), and indocyanine green angiography (10.2%). In 53 (49.1%) cases, flap salvage involved use of 1 modality, whereas in 55 (50.9%) cases multiple modalities were used. Factors associated with failure of these flap salvage tools included intraoperative arterial rather than postoperative arterial compromise (P = 0.01), and situations requiring use of a greater number of salvage modalities (P < 0.001).

Conclusions

We found that intraoperative compromise had significantly better prognosis than postoperative compromise. By organizing the numerous salvage modalities available to microsurgeons into a well‐defined algorithm that is supported by the literature, we have established a best practices protocol that has achieved flap salvage rates that compare favorably to the published literature. © 2013 Wiley Periodicals, Inc. Microsurgery 33:505–513, 2013.
The effect of learning curve on flap selection, re‐exploration, and salvage rates in free flaps; A retrospective analysis of 155 cases
Authors: Demir Ahmet , Kucuker Ismail , Keles Musa Kemal , Demirtas Yener
Published: August 2013

The purpose of this study is to report our experience and learning curve in avoiding complications at both the recipient and donor sites as well in choosing the best flap for different anatomic locations. For this purpose 155 free flaps done between October 2005 and August 2012 were retrospectively examined. Patient demographics, flap types, etiology, re‐exploration indications, timing of the re‐explorations, and salvage rates were documented. In the first 60 cases, our re‐exploration rate was 26.7% (16 flaps), and the rate decreased to 15.0% for the second 60 flaps (9 flaps). In correlation with this decrease, in the last 35 cases, only three flaps were re‐explored (8.6%). This decrease in re‐exploration rates over time was statistically significant (P = 0.021). Re‐exploration rates for axial and perforator flaps were 14.6% and 22.7%, respectively. Salvage rates were 76.9% in axial flaps and 53.3% in perforator flaps. The total success rate for axial flaps was 95.5% and for perforator flaps was 89.4%. Besides, re‐exploration rates were higher with lower salvage rates in perforator flaps compared to axial flaps causing lower overall success rates in the former group. The mean time of re‐explorations was 21.4 hours. Salvage rates were significantly higher in re‐explorations done within the first 12 hours after the initial surgery than in re‐explorations done after 12 hours (83.3% vs. 47.3%) (P = 0.040). We can conclude that axial flaps have a steeper learning curve and are safer options for the inexperienced reconstructive micro‐surgeons until they have adequate experience with the perforator dissection. © 2013 Wiley Periodicals, Inc. Microsurgery 33:519–526, 2013.
Z‐2‐(β‐d‐glucopyranosyloxy)‐3‐phenylpropenoic acid, an α‐hydroxy acid from rooibos (Aspalathus linearis) with hypoglycemic activity
Authors: Muller Christo J. F. , Joubert Elizabeth , Pheiffer Carmen , Ghoor Samira , Sanderson Micheline , Chellan Nireshni , Fey Stephen J. , Louw Johan
Published: August 2013

Scope

The rare enolic phenylpyruvic acid‐2‐O‐glucoside, (PPAG:Z‐2‐(β‐d‐glucopyranosyloxy)‐3‐phenylpropenoic acid), is one of the major constituents of fermented rooibos infusions. 3‐Phenylpyruvic acid (2‐oxo‐3‐phenylpropanoic acid), without the sugar moiety and with a keto form instead of an enolic arrangement, has been shown to enhance insulin release and glucose uptake in muscle cells. The purpose of this study was to assess if PPAG has similar activity on glucose metabolism.

Methods and results

Preliminary in vitro studies confirmed that PPAG, isolated from rooibos, enhanced glucose uptake. A dose–response study in Chang cells showed that PPAG enhanced glucose uptake in the concentration range 1.0–31.6 μM (EC50 = 3.6 μM). In obese insulin‐resistant rats, oral administration of PPAG lowered fasting glucose concentrations and improved oral glucose tolerance values; messenger RNA expression of glucokinase, glucose transporter 1 and 2, insulin receptor, peroxisome proliferator‐activated receptor alpha, and suppressor of cytokine signaling 3, were increased in the liver. This suggests that the liver is mainly responsible for PPAG bioactivity.

Conclusion

This study describes for the first time that PPAG increases in vitro glucose uptake and improves glucose tolerance in an obese insulin‐resistant rat model, suggesting that it has potential as a new class of antidiabetic therapeutics that would contribute to the antidiabetic effect of rooibos.
The Michigan incontinence symptom index (M‐ISI): A clinical measure for type, severity, and bother related to urinary incontinence
Authors: Suskind Anne M. , Dunn Rodney L. , Morgan Daniel M. , DeLancey John O.L. , McGuire Edward J. , Wei John T.
Published: August 2013

Aims

To develop a clinically relevant, easy to use, and validated instrument for assessing severity and bother related to urinary incontinence.

Methods

Survey items were piloted and refined following psychometric principles in five separate patient cohorts. Patient and expert endorsement of items, factor analyses, Spearman rank correlations and response distributions were employed for item selection. Formal reliability and validity evaluation were conducted for the final questionnaire items.

Results

Expert physicians and patient focus groups confirmed face and content validity for the measure. A 10‐item measure called the Michigan Incontinence Symptom Index (M‐ISI) was developed with two domains: a Total M‐ISI Domain consisting of subdomains for stress urinary incontinence, urgency urinary incontinence, and pad use, and a Bother Domain. High construct validity was demonstrated with a Cronbach's alpha for the Total M‐ISI Domain (items 1‐8) of 0.90 and for the Bother Domain (items 9‐10) of 0.82. Cronbach's alpha for the subdomains were all > 0.85. Construct validity, convergent and divergent validity, internal discriminant validity, and predictive validity were all robust. The minimally important difference for the measure was determined to be 4 points (out of 32) for the Total M‐ISI Severity Domain, and 1‐2 points (out of 8‐12) for the individual subdomains.

Conclusions

The M‐ISI is a parsimonious measure that has established reliability and validity on several levels and complements current clinical evaluative methods for patients with urinary incontinence. Neurourol. Urodynam. 33:1128–1134
, 2014. © 2013 Wiley Periodicals, Inc.
Quantitative MRI and ultrastructural examination of the cuprizone mouse model of demyelination
Authors: Thiessen Jonathan D. , Zhang Yanbo , Zhang Handi , Wang Lingyan , Buist Richard , Del Bigio Marc R. , Kong Jiming , Li Xin‐Min , Martin Melanie
Published: August 2013

The cuprizone mouse model of demyelination was used to investigate the influence that white matter changes have on different magnetic resonance imaging results. In vivo T2‐weighted and magnetization transfer images (MTIs) were acquired weekly in control (n = 5) and cuprizone‐fed (n = 5) mice, with significant increases in signal intensity in T2‐weighted images (p < 0.001) and lower magnetization transfer ratio (p < 0.001) in the corpus callosum of the cuprizone‐fed mice starting at 3 weeks and peaking at 4 and 5 weeks, respectively. Diffusion tensor imaging (DTI), quantitative MTI (qMTI), and T1/T2 measurements were used to analyze freshly excised tissue after 6 weeks of cuprizone administration. In multicomponent T2 analysis with 10 ms echo spacing, there was no visible myelin water component associated with the short T2 value. Quantitative MTI metrics showed significant differences in the corpus callosum and external capsule of the cuprizone‐fed mice, similar to previous studies of multiple sclerosis in humans and animal models of demyelination. Fractional anisotropy was significantly lower and mean, axial, and radial diffusivity were significantly higher in the cuprizone‐fed mice. Cellular distributions measured in electron micrographs of the corpus callosum correlated strongly to several different quantitative MRI metrics. The largest Spearman correlation coefficient varied depending on cellular type: T1 versus the myelinated axon fraction (ρ = −0.90), the bound pool fraction (ƒ) versus the myelin sheath fraction (ρ = 0.93), and axial diffusivity versus the non‐myelinated cell fraction (ρ = 0.92). Using Pearson's correlation coefficient, ƒ was strongly correlated to the myelin sheath fraction (r = 0.98) with a linear equation predicting myelin content (5.37ƒ − 0.25). Of the calculated MRI metrics, ƒ was the strongest indicator of myelin content, while longitudinal relaxation rates and diffusivity measurements were the strongest indicators of changes in tissue structure. Copyright © 2013 John Wiley & Sons, Ltd.
Global and local structural similarity in protein–protein complexes: Implications for template‐based docking
Authors: Kundrotas Petras J. , Vakser Ilya A.
Published: August 2013

The increasing amount of structural information on protein–protein interactions makes it possible to predict the structure of protein–protein complexes by comparison/alignment of the interacting proteins to the ones in cocrystallized complexes. In the predictions based on structure similarity, the template search is performed by structural alignment of the target interactors with the entire structures or with the interface only of the subunits in cocrystallized complexes. This study investigates the scope of the structural similarity that facilitates the detection of a broad range of templates significantly divergent from the targets. The analysis of the target‐template similarity is based on models of protein–protein complexes in a large representative set of heterodimers. The similarity of the biological and crystal packing interfaces, dissimilar interface structural motifs in overall similar structures, interface similarity to the full structure, and local similarity away from the interface were analyzed. The structural similarity at the protein–protein interfaces only was observed in ∼25% of target‐template pairs with sequence identity <20% and primarily homodimeric templates. For ∼50% of the target‐template pairs, the similarity at the interface was accompanied by the similarity of the whole structure. However, the structural similarity at the interfaces was still stronger than that of the noninterface parts. The study provides insights into structural and functional diversity of protein–protein complexes, and relative performance of the interface and full structure alignment in docking. Proteins 2013; 81:2137–2142. © 2013 Wiley Periodicals, Inc.
Quadratic‐in‐magnetization permittivity and conductivity tensor in cubic crystals
Authors: Hamrlová Jana , Hamrle Jaroslav , Postava Kamil , Pištora Jaromír
Published: August 2013

We present diagonal and off‐diagonal elements of the permittivity and conductivity tensor up to the second order in magnetization for cubic crystals. We express all tensor elements as a function of a general sample orientation, for arbitrary magnetization direction and for (001), (011), and (111) surface orientations. Finally, we discuss, how to extract values of quadratic elements G of the second‐order permittivity tensors for different sample surface orientations from both experiment and ab initio calculations.
Silicon surface passivation by aluminium oxide studied with electron energy loss spectroscopy
Authors: Hoex Bram , Bosman Michel , Nandakumar Naomi , Kessels W. M. M.
Published: August 2013

The origin behind crystalline silicon surface passivation by Al2O3 films is studied in detail by means of spatially‐resolved electron energy loss spectroscopy. The bonding configurations of Al and O are studied in as‐deposited and annealed Al2O3 films grown on c‐Si substrates by plasma‐assisted and thermal atomic layer deposition. The results confirm the presence of an interfacial SiO2‐like film and demonstrate changes in the ratio between tetrahedrally and octahedrally coordinated Al in the films after annealing. These observations reveal the underlying origin of c‐Si surface passivation by Al2O3. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effects of distilled water rinsing on stable isotope ratios of acid‐treated marine invertebrate (Paguridae) samples
Authors: Guerin Andrew J. , Jensen Antony C. , McGill Rona A. R.
Published: August 2013

RATIONALE

Stable isotope ratios are widely used to infer trophic relationships, although a growing number of studies show that sample pre‐treatments (such as acidification to remove carbonates) can cause changes in isotope ratios. Samples are often rinsed in distilled water after acidification, and we examine the effects of this step in particular on the isotope ratios of marine invertebrate samples.

METHODS

Samples of whole hermit crabs (Paguridae) were subjected to one of three treatments: acidification using dilute hydrochloric acid without subsequent distilled water rinsing; acidification with rinsing; and rinsing with no acidification. Continuous‐flow isotope ratio mass spectrometry was used to compare the mean carbon and nitrogen stable isotope ratios of treated and untreated material.

RESULTS

Acidification (both with and without subsequent distilled water rinsing) resulted in reductions in mean δ13C values (1.939 and 3.146‰, respectively), while rinsing without prior acidification led to a smaller (but still significant) increase. Nitrogen isotope ratios were not affected by acidification, but subsequent rinsing with distilled water caused a decrease of approximately 1‰.

CONCLUSIONS

Acidification of samples is clearly necessary in the presence of carbonates to obtain useful carbon isotope ratio data. However, post‐acidification rinsing can result in further (potentially undesirable) changes to both carbon and nitrogen isotope ratios. Ideally, rinsing should be avoided, but the impacts are small enough to be of little concern in many studies. Rinsing (or not) should be considered carefully on the basis of the aims of a study. Copyright © 2013 John Wiley & Sons, Ltd.
Stable carbon isotope analysis of dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC) in natural waters – Results from a worldwide proficiency test
Authors: van Geldern Robert , Verma Mahendra P. , Carvalho Matheus C. , Grassa Fausto , Delgado‐Huertas Antonio , Monvoisin Gael , Barth Johannes A. C.
Published: August 2013

RATIONALE

Stable carbon isotope ratios of dissolved inorganic (DIC) and organic carbon (DOC) are of particular interest in aquatic geochemistry. The precision for this type of analysis is typically reported in the range of 0.1‰ to 0.5‰. However, there is no published attempt that compares δ13C measurements of DIC and DOC among different laboratories for natural water samples.

METHODS

Five natural water samples (lake water, seawater, two geothermal waters, and petroleum well water) were analyzed for δ13CDIC and δ13CDOC values by five laboratories with isotope ratio mass spectrometry (IRMS) in an international proficiency test.

RESULTS

The reported δ13CDIC values for lake water and seawater showed fairly good agreement within a range of about 1‰, whereas geothermal and petroleum waters were characterized by much larger differences (up to 6.6‰ between laboratories). δ13CDOC values were only comparable for seawater and showed differences of 10 to 21‰ for other samples.

CONCLUSIONS

This study indicates that scatter in δ13CDIC isotope data can be in the range of several per mil for samples from extreme environments (geothermal waters) and may not yield reliable information with respect to dissolved carbon (petroleum wells). The analyses of lake water and seawater also revealed a larger than expected difference and researchers from various disciplines should be aware of this. Evaluation of analytical procedures of the participating laboratories indicated that the differences cannot be explained by analytical errors or different data normalization procedures and must be related to specific sample characteristics or secondary effects during sample storage and handling. Our results reveal the need for further research on sources of error and on method standardization. Copyright © 2013 John Wiley & Sons, Ltd.
Structural elucidation and identification of a new derivative of phenethylamine using quadrupole time‐of‐flight mass spectrometry
Authors: Sekuła Karolina , Zuba Dariusz
Published: August 2013

RATIONALE

In recent years, the phenomenon of uncontrolled distribution of new psychoactive substances that were marketed without prior toxicological studies has been observed. Because many designer drugs are related in chemical structure, the potential for misidentifying them is an important problem. It is therefore essential to develop an analytical procedure for unequivocal elucidation of the structures of these compounds. The issue has been discussed in the context of 25I‐NBMD [2‐(4‐iodo‐2,5‐dimethoxyphenyl)‐N‐[(2,3‐methylenedioxyphenyl)methyl]ethanamine], a psychoactive substance first discovered on the drug market in 2012.

METHODS

The substance was extracted from blotter papers with methanol. Separation was achieved via liquid chromatography. Analysis was conducted by electrospray ionization quadrupole time‐of‐flight mass spectrometry (ESI‐QTOFMS). Identification of the psychoactive component was supported by electron impact gas chromatography/mass spectrometry (GC/EI‐MS).

RESULTS

The high accuracy of the LC/ESI‐QTOFMS method allowed the molecular mass of the investigated substance (Mexp = 441.0438 Da; mass error, ∆m = 0.2 ppm) and the formulae of ions formed during fragmentation to be determined. The main ions were recorded at m/z = 135.0440, 290.9876 and 305.9981. Structures of the obtained ions were elucidated in the tandem mass spectrometry (MS/MS) experiments by comparing them to mass spectra of previously detected derivatives of phenethylamine.

CONCLUSIONS

The performed study indicated the potential for using LC/QTOFMS method to identify new designer drugs. This technique can be used supplementary to standard GC/MS. Prior knowledge of the fragmentation mechanisms of phenethylamines allowed to predict the mass spectra of the novel substance – 25I‐NBMD. Copyright © 2013 John Wiley & Sons, Ltd.
Semiglobal synchronization of multiple generic linear agents with input saturation
Authors: Wang Qingling , Yu Changbin , Gao Huijun
Published: August 2013

This paper investigates the semiglobal synchronization problem for a group of agents with input saturation under directed interaction topology, where each agent is modeled as a generic linear system rather than the single‐integrator or double‐integrator dynamics. The main result is the construction of a feedback coupling gain that achieves semiglobal synchronization if all the agents have identically saturated linear dynamics, which can be of any order. It is shown that the coupling gain obtained via parametric Lyapunov equations can semiglobally synchronize any directed network provided that the interaction topology has a directed spanning tree. Furthermore, due to the use of parametric Lyapunov equations, a convergence rate is analytically obtained. Finally, a simulation example is provided to demonstrate the effectiveness and advantages of our theoretical findings. Copyright © 2013 John Wiley & Sons, Ltd.
Iceland—Genetic Counseling Services
Authors: Stefansdottir Vigdis , Arngrimsson Reynir , Jonsson Jon J.
Published: August 2013

This brief report aims to give an overview of the history and current status of clinical genetics services in Iceland and specific genetic counseling considerations for Iceland's population. Presently, there are two part time medical geneticists and one full time genetic counselor with an MSc education from Cardiff, within the Department of Genetic and Molecular Medicine, based in Iceland's only tertiary healthcare facility, Landspitali, the National University Hospital. An oncologist (20 %) also contributes to the cancer genetic counseling service. In addition, a pediatric medical geneticist has a 25 % appointment at the Children's Hospital. No other health care organization offers genetic counseling, and there are no private genetic counseling services.
Lipid‐Modulating Treatments for Mixed Dyslipidemia Increase HDL‐Associated Phospholipase A2 Activity with Differential Effects on HDL Subfractions
Authors: Kei Anastazia , Liberopoulos Evangelos , Tellis Costantinos , Elisaf Moses , Tselepis Alexandros
Published: August 2013

The effect of lipid‐modulating treatments on modification of high density lipoprotein (HDL) subfractions remains unknown. In this study, mixed dyslipidemia patients (n = 100) inadequately controlled with a standard statin dose were randomized to switch to 40 mg of rosuvastatin or add‐on extended release nicotinic acid/laropiprant (ER‐NA/LRPT) or add‐on fenofibrate. The cholesterol concentrations of HDL (HDL‐C) subfractions and HDL‐associated lipoprotein‐associated phospholipase A2 (HDL‐Lp‐PLA2) activity were assessed at baseline and 3 months later. We observed that large HDL‐C increased by 50 and 6 % in the add‐on‐ER‐NA/LRPT and rosuvastatin groups, respectively, while it decreased by 20 % in the add‐on‐fenofibrate group (p < 0.01 vs baseline for all groups and p < 0.01 for all comparisons among groups). On the other hand, small HDL‐C decreased by 17 % in the add‐on‐ER‐NA/LRPT group (p < 0.01 vs baseline), while it increased by 25 % in the add‐on‐fenofibrate group (p < 0.01 vs baseline) without any change in the rosuvastatin group (p < 0.01 for all comparisons among groups). HDL‐Lp‐PLA2 activity increased by 55, 33 and 18 % in add‐on‐ER‐NA/LRPT, add‐on‐fenofibrate and rosuvastatin groups, respectively (p < 0.01 for all comparisons vs baseline and for all comparisons among groups). In conclusion, add‐on‐ER‐NA/LRPT was associated with an increase in large HDL‐C and a decrease in small HDL‐C, while opposite effects were noticed in the add‐on‐fenofibrate group. Add‐on‐ER‐NA/LRPT was associated with the most pronounced increase in HDL‐Lp‐PLA2 activity.
Multidimensional characterization of sexual minority adolescents' sexual safety strategies
Authors: Masters N. Tatiana , Beadnell Blair , Morrison Diane M. , Hoppe Marilyn J. , Wells Elizabeth A.
Published: August 2013

Young adults have high rates of sexually transmitted infections (STIs). Sexual minority youths' risk for STIs, including HIV, is as high as or higher than sexual majority peers'. Sexual safety, while often treated as a single behavior such as condom use, can be best conceptualized as the result of multiple factors. We used latent class analysis to identify profiles based on ever‐used sexual safety strategies and lifetime number of partners among 425 self‐identified LGBTQ youth aged 14–19. Data collection took place anonymously online. We identified four specific subgroup profiles for males and three for females, with each subgroup representing a different level and type of sexual safety. Profiles differed from each other in terms of age and outness for males, and in outness, personal homonegativity, and amount of education received about sexual/romantic relationships for females. Youths' sexual safety profiles have practice implications for sexuality educators, health care professionals, and parents.
Hip Development after Selective Dorsal Rhizotomy in Patients with Cerebral Palsy
Authors: Wai-Ming Chan , Alexander Choi Kai-Yiu , Kin-Wai Sun , Dawson Fong , Kwong-Yui Yam
Published: August 2013

Objective

The effects of selective dorsal rhizotomy (SDR) on the hip development in children with spastic cerebral palsy (CP) are not well defined. The present study was performed to determine the effects of SDR and other associated clinical and radiological factors on the outcome of hip development after SDR.

Methods

The study included 53 patients who were skeletally immature at the time of SDR. Between 2003 and 2010, they underwent SDR at our institute. The age ranged from 4 to 15 years old. Their preoperative hip status was divided into two groups: normal and abnormal. The final outcome of the hip was considered good if the centre-edge angle of Wiberg (CEA) at last follow-up was more than 20 degrees without the need for orthopaedic intervention. Thirty-seven patients satisfied the inclusion criteria for statistical analysis.

Results

Seventeen patients were in the “Normal pre-op” group. In all patients (except for two patients), the hip status remained normal after the SDR. Twenty patients were in the “Abnormal pre-op” group. In this group, only two patients returned to normal hips, whereas 11 patients required orthopaedic hip surgery within 5 years after the SDR. The remaining seven patients had hip subluxation, but not to the extent of hip dislocation. The preoperative hip radiological measurements and functional status were positively correlated with the postoperative hip status. The preoperative radiological measurements showed superior predictive value when other covariance were considered. No difference of outcome existed in regard to the different surgical approaches of SDR.

Conclusion

Selective dorsal rhizotomy has a neutral effect on hip development. The preoperative hip radiological measurement is the most important predictive factor to determine hip status after SDR. Good collaboration between neurosurgeons and paediatric orthopaedists is essential for the best management of these patients.
Cooperación internacional para el desarrollo en el Valle del Cauca: un estudio de percepciones
Authors: Otálora Sevilla Lady Maritza , Rouvinski Vladimir
Published: August 2013

Este artículo analiza las percepciones de los actores de la cooperación internacional en el Departamento del Valle del Cauca sobre los procesos de cooperación internacional para el desarrollo. Los autores, luego de analizar las entrevistas en profundidad con distintos actores y documentos relevantes en la cooperación internacional en la región, argumentan que las percepciones de los actores clave inciden fuertemente en los procesos de cooperación, y destacan una diversidad muy amplia en las percepciones acerca de los mismos aspectos de cooperación internacional expresadas por los representantes del sector público, las organizaciones internacionales y los del sector privado, que no permiten una mejor coordinación de los flujos de cooperación internacional en la región.
Caracterización del comprador sogamoseño en súper e hipermercados
Authors: Sanabria Torres Edgar , Parra Penagos Carlos Orlando
Published: August 2013

El objetivo del trabajo es caracterizar el comprador sogamoseño de súper e hipermercados con base en el modelo de Blackwell, Miniard & Engel (2003) y el soporte de Aaker & Day (1989), para así decantar en 4 variables: supermercado preferido, ambiente físico, aprendizaje y actitudes y, por último, la frecuencia de uso. Se utilizó un tipo de investigación cuantitativo en una población referenciada por los hogares pertenecientes a la ciudad de Sogamoso, Colombia (DANE, 2005). Se concluye que dichas variables inciden de forma importante en la decisión de compra del comprador al determinar qué lugar tiene mejores atributos según el estilo de vida y necesidades del mismo.
Diseño metodológico de la evaluación de proyectos energéticos bajo incertidumbre en precios: caso de cogeneración de energía en una empresa en Cali
Authors: Núñez Viveros Carlos Andrés , Gallego Hidalgo Gabriel José , Buenaventura Vera Guillermo
Published: August 2013

Los recursos energéticos en la industria recobran mayor relevancia en su competitividad, representando el segundo o tercer rubro en el costo. El comportamiento fluctuante de los costos históricos, así como la incertidumbre de su tendencia futura, acentuada por la inminencia del desmonte del impuesto de contribución en energía eléctrica (20% de la tarifa), conllevan el cuestionamiento de si los proyectos de cogeneración de energía tendrán viabilidad en un futuro cercano. El presente trabajo desarrolla una metodología innovadora para evaluar la viabilidad de la implementación de proyectos de cogeneración, fundamentada en 3 simuladores que trabajan con información estadística y proyecciones matemáticas, además de realizar un análisis de sensibilidad del proyecto a los comportamientos proyectados de los precios futuros de la energía eléctrica y de los combustibles.
Modelos de valoración de opciones sobre títulos de renta fija: aplicación al mercado colombiano
Authors: Herrera Cardona Luis Guillermo , Cárdenas Giraldo Darwin
Published: August 2013

Este documento tiene como propósito evaluar la aplicabilidad del modelo de tasa de interés de Vasicek (1977) para la valorar opciones call y put sobre un título de renta fija colombiano. Para el desarrollo de esta aplicación, se efectúan estimaciones econométricas con procesos autorregresivos y de volatilidad necesarias para encontrar los parámetros de entrada del modelo. En el avance del trabajo se encuentra que este no arroja resultados satisfactorios para las opciones sobre bonos colombianos, debido al alto valor de las primas. Sin embargo, ajustando el modelo con parámetros basados en criterios empíricos, se obtienen cifras más consistentes.
Incidencia de la certificación ISO 9001 en los indicadores de productividad y utilidad financiera de empresas de la zona industrial Mamonal en Cartagena
Authors: Morelos Gómez José , Fontalvo Tomas José , Vergara Juan Carlos
Published: August 2013

Este artículo de investigación presenta los resultados de evaluación de indicadores de productividad de las empresas certificadas en ISO 9001 y su incidencia en la utilidad financiera de las empresas de la Zona Industrial Mamonal en Cartagena. En la metodología utilizada se calcularon los indicadores de productividad y financieros, a las 25 empresas certificadas en calidad. Seguidamente, se utilizó la técnica de análisis multivariante de datos, para explicar la pertenencia y discriminación de cada grupo de indicadores de productividad y financieros, teniendo como resultado el mejoramiento en la eficiencia productiva de los indicadores razón utilidad bruta/valor agregado (IP1) y razón utilidad neta/capital de trabajo (IP4) entre 2006 y 2010, y por ende la positiva incidencia de estos indicadores en las utilidades financieras, margen bruto (MB) y margen operacional (MO).
Turbulence spectra in smooth- and rough-wall pipe flow at extreme Reynolds numbers
Authors: Rosenberg B. J. , Hultmark M. , Vallikivi M. , Bailey S. C. C. , Smits A. J.
Published: August 2013

Well-resolved streamwise velocity spectra are reported for smooth- and rough-wall turbulent pipe flow over a large range of Reynolds numbers. The turbulence structure far from the wall is seen to be unaffected by the roughness, in accordance with Townsend’s Reynolds number similarity hypothesis. Moreover, the energy spectra within the turbulent wall region follow the classical inner and outer scaling behaviour. While an overlap region between the two scalings and the associated${ k}_{x}^{- 1} $law are observed near${R}^{+ } \approx 3000$, the${ k}_{x}^{- 1} $behaviour is obfuscated at higher Reynolds numbers due to the evolving energy content of the large scales (the very-large-scale motions, or VLSMs). We apply a semi-empirical correction (del Álamo & Jiménez,J. Fluid Mech., vol. 640, 2009, pp. 5–26) to the experimental data to estimate how Taylor’s frozen field hypothesis distorts the pseudo-spatial spectra inferred from time-resolved measurements. While the correction tends to suppress the long wavelength peak in the logarithmic layer spectrum, the peak nonetheless appears to be a robust feature of pipe flow at high Reynolds number. The inertial subrange develops around${R}^{+ } \gt 2000$where the characteristic${ k}_{x}^{- 5/ 3} $region is evident, which, for high Reynolds numbers, persists in the wake and logarithmic regions. In the logarithmic region, the streamwise wavelength of the VLSM peak scales with distance from the wall, which is in contrast to boundary layers, where the superstructures have been shown to scale with boundary layer thickness throughout the entire shear layer. Moreover, the similarity in the streamwise wavelength scaling of the large- and very-large-scale motions supports the notion that the two are physically interdependent.
Diffusiophoresis of colloidal particles in neutral solute gradients at finite Péclet number
Authors: Khair Aditya S.
Published: August 2013

The role of neutral solute advection on the diffusiophoretic motion of colloidal particles is quantified. Theoretical analyses of this phenomenon usually assume that the solute concentration evolves solely via diffusion; that is, the Péclet number ($\mathit{Pe}$) for solute transport is identically zero. This leads to the conclusion that the translational diffusiophoretic velocity of a colloid is independent of its size, shape, and orientation with respect to the imposed solute gradient, provided that the colloid has uniform surface properties and that the length scale of interaction between the solute and the particle surface is much smaller than the particle size (Morrison, J. Colloid Interface Sci. vol. 34, 1970, p. 210). For a single spherical colloid, we show that the particle velocity decreases monotonically with increasing $\mathit{Pe}$. Moreover, the solute concentration and fluid flow around the colloid become markedly fore–aft asymmetric as $\mathit{Pe}$ is increased. Next, an asymptotic expansion at small $\mathit{Pe}$ predicts that solute advection leads to relative phoretic motion between two identical spherical colloids, which ultimately align in a plane normal to the imposed gradient (there is no relative motion at $\mathit{Pe}= 0$). Finally, asymptotic analysis of the diffusiophoretic motion of a slightly non-spherical colloid at small $\mathit{Pe}$ demonstrates that advection leads to a shape- and orientation-dependent particle velocity, in contrast to the insensitivity of the velocity to shape and orientation at $\mathit{Pe}= 0$.
Experiments on gravity currents propagating on different bottom slopes
Authors: Dai Albert
Published: August 2013

Experiments for gravity currents generated from an instantaneous buoyancy source propagating on an inclined boundary in the slope angle range ${0}^{\circ } \leq \theta \leq {9}^{\circ } $ are reported. While the flow patterns for gravity currents on $\theta = {6}^{\circ } , {9}^{\circ } $ are qualitatively different from those on $\theta = {0}^{\circ } $, similarities are observed in the acceleration phase for the flow patterns between $\theta = {2}^{\circ } $ and $\theta = {6}^{\circ } , {9}^{\circ } $ and in the deceleration phase, the patterns for gravity currents on $\theta = {2}^{\circ } $ are found similar to those on $\theta = {0}^{\circ } $. Previously, it was known that the front location history in the deceleration phase obeys a power-relationship, which is essentially an asymptotic form of the solution to thermal theory. We showed that this power-relationship applies only in the early stage of the deceleration phase, and when gravity currents propagate into the later stage of the deceleration phase, viscous effects become more important and the front location data deviate from this relationship. When the power-relationship applies, it is found that at $\theta = {9}^{\circ } $, ${u}_{f} {({x}_{f} + {x}_{0} )}^{1/ 2} / {{ B}_{0}^{\prime } }^{1/ 2} \approx 2. 8{ 8}_{- 0. 17}^{+ 0. 19} $, which changes to $2. 8{ 6}_{- 0. 13}^{+ 0. 13} $ at $\theta = {6}^{\circ } $, $2. 5{ 4}_{- 0. 07}^{+ 0. 08} $ at $\theta = {2}^{\circ } $, and $1. 5{ 1}_{- 0. 07}^{+ 0. 07} $ on a horizontal boundary, where ${u}_{f} $ is the front velocity, $({x}_{f} + {x}_{0} )$ is the front location measured from the virtual origin, and ${ B}_{0}^{\prime } $ is the released buoyancy. Our results indicate that in the slope angle range ${6}^{\circ } \leq \theta \leq {9}^{\circ } $, the asymptotic relationship between the front velocity and front location in the deceleration phase is not sensitive to the variation of slope angle. In the late deceleration phase when the front location data deviate from the power-relationship, we found that the flow patterns for $\theta = {6}^{\circ } , {9}^{\circ } $ are dramatically different from those for $\theta = {0}^{\circ } , {2}^{\circ } $. For high slope angles, i.e. $\theta = {6}^{\circ } , {9}^{\circ } $, the edge of the gravity current head experiences a large upheaval and enrolment by ambient fluid towards the end of the deceleration phase, while for low slope angles, i.e. $\theta = {0}^{\circ } , {2}^{\circ } $, the gravity current head maintains a more streamlined shape without violent mixing with ambient fluid throughout the course of gravity current propagation. Our findings indicate two plausible routes to the finale of a gravity current event.