bluuebunny/crossref_metadata_2025 huggingface dataset:
Human myogenic endothelial cells exhibit chondrogenic and osteogenic potentials at the clonal level
Authors: Zheng Bo , Li Guangheng , Chen William C.W. , Deasy Bridget M. , Pollett Jonathan B. , Sun Bin , Drowley Lauren , Gharaibeh Burhan , Usas Arvydas , Péault Bruno , Huard Johnny
Published: April 2013

We have previously reported the high regenerative potential of murine muscle‐derived stem cells (mMDSCs) that are capable of differentiating into multiple mesodermal cell lineages, including myogenic, endothelial, chondrocytic, and osteoblastic cells. Recently, we described a putative human counterpart of mMDSCs, the myogenic endothelial cells (MECs), in adult human skeletal muscle, which efficiently repair/regenerate the injured and dystrophic skeletal muscle as well as the ischemic heart in animal disease models. Nevertheless it remained unclear whether human MECs, at the clonal level, preserve mMDSC‐like chondrogenic and osteogenic potentials and classic stem cell characteristics including high proliferation and resistance to stress. Herein, we demonstrated that MECs, sorted from fresh postnatal human skeletal muscle biopsies, can be grown clonally and exhibit robust resistance to oxidative stress with no tumorigeneity. MEC clones were capable of differentiating into chondrocytes and osteoblasts under inductive conditions in vitro and participated in cartilage and bone formation in vivo. Additionally, adipogenic and angiogenic potentials of clonal MECs (cMECs) were observed. Overall, our study showed that cMECs not only display typical properties of adult stem cells but also exhibit chondrogenic and osteogenic capacities in vitro and in vivo, suggesting their potential applications in articular cartilage and bone repair/regeneration. © 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:1089–1095, 2013
Connection between the vibrational dynamics and the cross‐linking properties in cyclodextrins‐based polymers
Authors: Crupi Vincenza , Fontana Aldo , Giarola Marco , Majolino Domenico , Mariotto Gino , Mele Andrea , Melone Lucio , Punta Carlo , Rossi Barbara , Trotta Francesco , Venuti Valentina
Published: April 2013

The vibrational dynamics of a new class of cross‐linked polymers obtained from both native and modified cyclodextrin, referred to as cyclodextrin nanosponges, is here investigated. The main purpose is to spot the structure of these materials at molecular level unlikely to be characterized by diffraction methods due to the low or null degree of crystallinity. The analysis of the spectral features of the vibrational bands observed between 1650 and 1800 cm−1 in both Raman and infrared spectra, and assigned to the carbonyl stretching modes of the polymeric network, is performed by using band deconvolution procedures. At the same time, a detailed inspection of the low‐wavenumber vibrational dynamics of these polymers is carried out, focusing on the modifications occurring on the so‐called boson peak.

The simultaneous analysis of different wavenumber ranges in Raman and infrared spectra of cyclodextrin nanosponges allows us to develop a reliable strategy for exploring both the cross‐linking degree and the elastic properties of these innovative materials. The overall results give a complete characterization of the structural and dynamical properties of the system, in turn strictly connected to the entrapment/transport ability of these polymeric matrices. Copyright © 2013 John Wiley & Sons, Ltd.
The Increasing role of otolaryngology in the management of surgical thyroid disorders
Authors: Chambers Kyle J. , Bhattacharyya Neil
Published: April 2013

Objectives/Hypothesis

To determine trends in office visits and medical specialty seen for surgical diagnoses of the thyroid gland.

Study Design

A cross‐sectional analysis of a national healthcare database.

Methods

From the National Ambulatory Medical Care Survey (NAMCS), all cases of surgical thyroid disorders (e.g., benign neoplasm of thyroid gland, malignant neoplasm of thyroid gland, multinodular goiter) were extracted for 2 calendar year cohorts: 1995 to 1999 and 2005 to 2009. In addition to demographic information, the medical specialty of the health care provider seen was extracted. Comparisons were conducted for the proportion of surgical thyroid cases seen between general surgeons and otolaryngologists for the respective cohorts.

Results

In the 1995 to 1999 cohort, there were a total of 107 ± 13 thousand outpatient visits annually to either general surgery or otolaryngology for surgical thyroid conditions. Among these, 62.7 ± 8.4 thousand visits (58.3 ± 5.6%) were seen by general surgery versus 44.8 ± 9.1 thousand (41.7 ± 5.6%) seen by otolaryngology. In comparison, in the 2005 to 2009 cohort, there were 218 ± 29 thousand visits annually for surgical thyroid conditions. Among these, 88.4 ± 17 thousand (40.5 ± 5.4%) were seen by general surgery versus 130 ± 21 thousand (59.5 ± 5.4%) seen by otolaryngology. The increase in proportion of surgical thyroid patients seen by otolaryngology in the second 5 year cohort was statistically significant (P = 0.032, chi‐square).

Conclusions

There is a national trend in the United States toward otolaryngologists seeing an increasing majority proportion of increasingly prevalent surgical thyroid conditions. These data objectively confirm the perceived increasing role of otolaryngologists in the management of surgical thyroid disorders on a national level.

Level of Evidence

2a. Laryngoscope, 123:3239–3242, 2013
Improvement in the detection of locoregional recurrence in head and neck malignancies: F‐18 fluorodeoxyglucose–positron emission tomography/computed tomography compared to high‐resolution contrast‐enhanced computed tomography and endoscopic examination
Authors: Rangaswamy Balasubramanya , Fardanesh M. Reza , Genden Eric M. , Park Eunice E. , Fatterpekar Girish , Patel Zara , Kim Jongho , Som Peter M. , Kostakoglu Lale
Published: April 2013

Objectives/Hypothesis

To compare the diagnostic efficacy of positron emission tomography (PET) with F‐18 fluorodeoxyglucose (FDG‐PET)/computed tomography (CT) to that of contrast‐enhanced high‐resolution CT (HRCT) and assess the value of a combinatorial approach in detection of recurrent squamous cell cancer of the head and neck (HNC) and to assess the efficacy of FDG‐PET/CT with and without HRCT in comparison to standard‐of‐care follow‐up—physical examination (PE) and endoscopy (E)—in determination of locally recurrent HNC.

Study Design

Retrospective study.

Methods

A total of 103 patients with HNC underwent FDG‐PET/CT and neck HRCT. There were two groups of patients: Group A had an FDG‐PET study acquired with low‐dose CT, and group B had an FDG‐PET study acquired with HRCT. The PET data obtained with or without HRCT were compared on a lesion and patient basis with the results of the PE/E.

Results

On a lesion basis, both groups combined had higher sensitivity and negative predictive value (NPV) than the HRCT. Specificity and positive predictive value (PPV) for group B were higher than for group A. On a patient basis, both groups combined had a higher sensitivity and NPV than PE/E, respectively, although specificity of PE/E was higher than that of either group. PET data obtained with either protocol directly influenced treatment.

Conclusions

HRCT increases the specificity and PPV of PET/CT when acquired simultaneously with PET. FDG‐PET/CT acquired with either LDCT or HRCT has higher accuracy than HRCT alone and increases the sensitivity and NPV of PE/E.

Level of Evidence

4 Laryngoscope, 123:2664–2669, 2013
Long‐term outcomes of surgery followed by radiation therapy for minor salivary gland carcinomas
Authors: Zeidan Youssef H. , Shultz David B. , Murphy James D. , An Yi , Chan Cato , Kaplan Michael J. , Colevas A. Dimitrios , Kong Christina , Chang Daniel T. , Le Quynh‐Thu
Published: April 2013

Objectives/Hypothesis

Postoperative radiation therapy is often used in patients with high‐risk salivary gland carcinomas. In this study we evaluated the outcomes and prognostic factors in patients with minor salivary gland cancers treated with adjuvant radiation therapy.

Study Design

Retrospective cohort study.

Methods

We performed a retrospective analysis of 90 patients treated with curative intent. Median follow‐up was 71 months. Fifty‐eight patients (64%) had adenoid cystic carcinomas, 22 (24%) had adenocarcinomas, and 10 (11%) had mucoepidermoid cancers. Primary disease site included 39 (43%) sinonasal, 35 (39%) oral cavity, 10 (11%) oropharynx, and six (7%) others. Twenty‐seven patients (30%) were treated with intensity‐modulated radiation therapy.

Results

Eight local, four neck, and 24 distant relapses were detected. Local control rates at 5 and 10 years were 90% and 88%, respectively. Advanced T stage was associated with worse local control. Distant metastasis rates were 24% and 28% at 5 and 10 years, respectively. Tumor stage, histology, perineural invasion, and lymphovascular space invasion were significant predictors of distant metastasis on univariate analysis. However, on multivariate analysis only the American Joint Committee on Cancer stage was significant. Overall survival rates were 76% and 63% at 5 and 10 years, respectively. More advanced T stage and N stage correlated with worse overall survival.

Conclusions

Tumor stage remains the best predictor for locoregional and distant disease control of minor salivary gland cancers. Postoperative radiation therapy for high‐risk patients results in excellent long‐term locoregional disease control. Further work is needed to improve systemic control.

Level of Evidence

4. Laryngoscope, 123:2675–2680, 2013
Regenerative phonosurgical treatments for vocal fold scar and sulcus with basic fibroblast growth factor
Authors: Hirano Shigeru , Mizuta Masanobu , Kaneko Mami , Tateya Ichiro , Kanemaru Shin‐Ichi , Ito Juichi
Published: April 2013

Objectives/Hypothesis

Vocal fold scar and sulcus are still challenges. Basic fibroblast growth factor (bFGF) has proven to be effective to resolve scar tissue in animal models. This study reports the efficacy of regenerative treatments using bFGF on vocal fold scar and sulcus in human cases.

Study Design

Retrospective chart review.

Methods

Fifteen cases (7 scar; 8 sulcus) were treated by either local injection of bFGF (n = 6) or regenerative surgery using bFGF (n = 9). Injection regimen was to locally apply 10 micrograms of bFGF in 0.5 mL saline into each vocal fold under topical anesthesia repeatedly (4 times with intervals of 1 week between each injection). The regenerative surgical procedure consisted of the dissection of scar tissue and the implant of gelatin sponge with bFGF. Follow‐up periods ranged from 6 months to 24 months.

Results

Maximum Phonation Time (MPT); Voice Handicap Index (VHI)−10; and Grade, Roughness, Breathiness, Asthenia, Strain (GRBAS) scale were assessed in both groups. The injection group showed significant improvement on VHI‐10 and GRBAS. The regenerative surgery group showed significant improvement in all parameters. Jitter and shimmer were evaluated in the surgery group, and the results indicated improvement in six and five cases of nine cases, respectively. No major adverse effects were observed in both treatment groups.

Conclusions

Regenerative treatments using bFGF has shown to be effective for improvement of vocal function in scar and sulcus.

Level of Evidence

4. Laryngoscope, 123:2749–2755, 2013
Five adult laryngeal venous malformation cases treated effectively with sclerotherapy
Authors: Kamijo Atsushi , Hatsushika Kyousuke , Kanemaru Syuichiro , Moriyama Motohiro , Kase Yasuhiro , Masuyama Keisuke
Published: April 2013

Objectives/Hypothesis

Laryngeal venous malformation is a comparatively rare condition in adults. It presents as a livid or bluish mass that may cause bleeding, hoarseness, stridor, and even difficulty in breathing. So far, treatment has largely consisted of laser therapy and surgical removal. Five cases of adult laryngeal venous malformations that were treated by sclerotherapy (local injection of monoethanolamine oleate solution) are reported. All lesions disappeared after one or two treatment sessions, and two of the five cases that presented recently were cured in the outpatient clinic setting with no sequelae. Sclerotherapy with monoethanolamine oleate is a safe, easy, and effective treatment for laryngeal venous malformations.

Level of Evidence

4. Laryngoscope, 123:2766–2769, 2013
Bilateral modified nasoseptal “rescue” flaps in the endoscopic endonasal transsphenoidal approach
Authors: Kim Boo Young , Shin Ji‐Hyeon , Kang Seok‐Gu , Kim Sung Won , Hong Yong Kil , Jeun Sin‐Soo , Kim Soo Whan , Cho Jin Hee , Park Yong Jin
Published: April 2013

Objectives/Hypothesis

For a wide exposure of skull base and preservation of septal mucosa, we have raised bilateral modified nasoseptal rescue flaps in the endoscopic endonasal transsphenoidal approach (EETSA) and evaluated the usefulness of these flaps elevation.

Study Design

Case series.

Methods

The study population comprised the patients who underwent EETSA with bilateral modified nasoseptal rescue flaps elevation between February 2009 and June 2012. We retrospectively reviewed patients' medical records. Patients underwent preoperative nasal evaluation using the Nasal Obstruction Symptom Evaluation (NOSE), Sino‐Nasal Outcome Test (SNOT‐20), and a visual analogue scale (VAS) to assess several nasal symptoms. Repeat testing was performed 6 months postoperatively.

Results

A total of 92 patients underwent the EETSA with bilateral modified nasoseptal rescue flaps elevation. A total of 17 patients had intraoperative cerebrospinal fluid (CSF) leakage. Three patients underwent extension of the modified nasoseptal rescue flap to a conventional nasoseptal flap. No patients underwent reoperation due to CSF leakage. There was no statistical difference between preoperative and postoperative total SNOT‐20 and NOSE scores. According to the VAS, subjective olfaction function statistically worsened (P = 0.011) postoperatively.

Conclusion

Bilateral modified nasoseptal rescue flaps elevation provided good exposure of the sellar floor, preserved the septal branch of sphenopalatine artery, and facilitated removal of sellar tumors. We could also preserve more septal mucosa by designing a novel incision and repositioning unused flaps to their original sites. Postoperative complications of the nasal cavity were thus minimized. We believe that this flap is very useful in a variety of settings during the EETSA.

Level of Evidence

4. Laryngoscope, 123:2605–2609, 2013
BAX/BCL2 RMFI ratio predicts better induction response in pediatric patients with acute myeloid leukemia
Authors: Sharawat Surender Kumar , Bakhshi Radhika , Vishnubhatla Sreenivas , Gupta Ritu , Bakhshi Sameer
Published: April 2013

BAX/BCL2 ratio in pediatric AML has not been evaluated. In this first prospective study, we evaluated BAX/BCL2 transcript and RMFI ratio in 64 patients using real‐time PCR (TaqMan Probe chemistry) and flow‐cytometry, respectively. There was no correlation of BAX/BCL2 transcript ratio with RMFI ratio (R = −0.05; P = 0.715). Patients with WBC count >50,000/mm3 had lower BAX/BCL2 RMFI ratio (P = 0.043), whereas no difference in ratio was observed among patients of different cytogenetics subgroups (P = 0.786). Higher BAX/BCL2 RMFI ratio was associated positively with CR rate (P = 0.03), but this study was unable to show that it translated into improved EFS or OS. Pediatr Blood Cancer 2013;60E63‐E66. © 2013 Wiley Periodicals, Inc.
Noninvasive fetal genome sequencing: a primer
Authors: Snyder Matthew W. , Simmons LaVone E. , Kitzman Jacob O. , Santillan Donna A. , Santillan Mark K. , Gammill Hilary S. , Shendure Jay
Published: April 2013

We recently demonstrated whole genome sequencing of a human fetus using only parental DNA samples and plasma from the pregnant mother. This proof‐of‐concept study demonstrated how samples obtained noninvasively in the first or second trimester can be analyzed to yield a highly accurate and substantially complete genetic profile of the fetus, including both inherited and de novo variation. Here, we revisit our original study from a clinical standpoint, provide an overview of the scientific approach, and describe opportunities and challenges along the path toward clinical adoption of noninvasive fetal whole genome sequencing. © 2013 John Wiley & Sons, Ltd.
Hypoactive Sexual Desire Disorder in Women: Treatment Options Beyond Testosterone and Approaches to Communicating with Patients on Sexual Health
Authors: Lodise Nicole M.
Published: April 2013

Hypoactive sexual desire disorder (HSDD) affects nearly 1 in 10 women. Thus, it is essential for pharmacists and other health care providers to be comfortable when discussing a patient's sexual health to ensure appropriate triage so that the specific causes of HSDD can be identified and potential recommendations provided. HSDD is defined as the absence or deficiency of sexual interest and/or desire, leading to significant distress and interpersonal difficulties. As health care providers, pharmacists have a critical role in assessing the presence of HSDD and providing education on available treatment options. This article will review the potential causes of HSDD and low sexual desire, the screening tools available, and the significant role of health care professionals in communicating with patients about their sexual health. An overview of the importance of behavioral modifications, the current pharmacologic options being investigated, and the use of complementary and alternative therapies will also be explored. Currently, buproprion is the primary pharmacologic agent that has shown positive results in treating patients with HSDD. The use of testosterone therapy will not be addressed in this article, as this therapy is described in greater detail elsewhere.
Evaluation of Proprotein Convertase Subtilisin/Kexin Type 9: Focus on Potential Clinical and Therapeutic Implications for Low‐Density Lipoprotein Cholesterol Lowering
Authors: Lose Jennifer M. , Dorsch Michael P. , Bleske Barry E.
Published: April 2013

Reduction in low‐density lipoprotein cholesterol (LDL‐C) is associated with a decrease in coronary heart disease (CHD). Statins are currently the most effective medications for LDL‐C lowering; however, there continues to be a residual risk for cardiovascular events. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a protease that promotes LDL receptor degradation, leading to an increase in LDL‐C blood levels. Patients with PCSK9 gain‐of‐function mutations can have up to a 20‐fold increase in associated CHD compared with patients without these mutations. Conversely, patients with PCSK9 loss‐of‐function mutations can have up to an 88% reduction in CHD without any deficits in neurologic or physiologic functions. PCSK9 can be modulated by current antihyperlipidemic therapies. In particular, statins lead to an increase in PCSK9, which may attenuate their full lipid‐lowering effects. These attributes have made PCSK9 inhibition a desirable target for future drug therapies. Current investigational modalities inhibiting PCSK9 will also be discussed.
The Evolving Role of Antifungal Susceptibility Testing
Authors: Eschenauer Gregory A. , Carver Peggy L.
Published: April 2013

Although increasing numbers of hospital microbiology laboratories are performing antifungal susceptibility testing (AST), its routine use is uncommon. The utility of AST is founded on the belief that susceptibility (or resistance) of an agent allows some prediction of clinical outcome. This review provides an overview of the development of antifungal susceptibility testing methodology, including wild‐type minimum inhibitory concentration (MIC) distributions, epidemiologic breakpoints, and Interpretive Clinical Breakpoints for antifungal agents. In addition, we examine the current clinical utility of AST and the clinical data support utilized in the development of clinical breakpoints (CBP) for common pathogens causing invasive fungal infections. In the treatment of fungal infections, identifying consistent correlations between MICs – or susceptibility category – and clinical outcomes is an ongoing challenge, and current data sets are insufficient for many drugs and pathogens to enable the development, revision, or confirmation of CBPs. Antifungal susceptibility testing is of current value, but further research in many areas is needed before MICs are independently used to guide treatment decisions.
Gentamicin Pharmacokinetics and Dosing in Neonates with Hypoxic Ischemic Encephalopathy Receiving Hypothermia
Authors: Frymoyer Adam , Meng Lina , Bonifacio Sonia L. , Verotta Davide , Guglielmo B. Joseph
Published: April 2013

Study Objective

To evaluate the pharmacokinetics of gentamicin in neonates with hypoxic ischemic encephalopathy (HIE) receiving hypothermia and to identify an empiric gentamicin dosing strategy in this population that optimizes achievement of target peak and trough concentrations.

Design

Population pharmacokinetic study using retrospective medical record data.

Setting

Tertiary neonatal intensive care unit.

Patients

A total of 29 full‐term neonates diagnosed with HIE treated with hypothermia who received gentamicin and underwent therapeutic drug monitoring

Measurement and Main Results

Patient demographics and gentamicin concentration data were retrospectively collected over a 2‐year period. A population‐based pharmacokinetic model was developed using nonlinear mixed‐effects modeling (NONMEM). Using the developed model, Monte Carlo simulations were performed to evaluate the probability of achieving target peak (> 6 mg/L) and trough (< 2 mg/L) gentamicin concentrations for various potential dosing regimens. A one‐compartment model best described the available gentamicin concentration data. Birthweight and serum creatinine significantly influenced gentamicin clearance. For the typical study neonate (birthweight 3.3 kg, serum creatinine 0.9 mg/dl), clearance was 0.034 L/hour/kg and volume was 0.52 L/kg. At a 24‐hour dosing interval, Monte Carlo simulations predicted target gentamicin peak and trough concentrations could not be reliably achieved at any dose. At a 36‐hour dosing interval, a dose of 4–5 mg/kg is predicted to achieve target gentamicin peak and trough concentrations in more than 90% of neonates.

Conclusions

Gentamicin clearance is decreased in neonates with HIE treated with hypothermia compared with previous reports in nonasphyxiated normothermic full‐term neonates. A prolonged 36‐hour dosing interval will be needed to achieve target gentamicin trough concentrations in this population. Further prospective evaluation of this dosing recommendation is needed.
Additivity of substituent effects on the acidity of alcohols
Authors: Abboud José‐Luis M. , Koppel Ilmar A. , Koppel Ivar
Published: April 2013

Using Fourier Transform Ion Cyclotron Resonance Spectrometry, we have determined the gas‐phase acidities (GA) of 1‐phenylethanol, diphenylmethanol and triphenylmethanol. Combining these results with the available experimental data for other alcohols, we obtained three sets of experimental acidities for the families (CH3)nC–OH, (CF3)nC–OH and PhnC–OH (n = 1–3) as well for some other α‐substituted alcohols combining these substituents. GA values for these alcohols were studied at the B3LYP/6‐311 + G(d,p), MP2/6‐311 + G(d,p), G3(MP2) and G3 levels. This allowed the prediction of a number of GA values for other alcohols. We also developed an empirical method for the estimation of these magnitudes and used it to predict the cases wherein simple additivity of substituent effects would break down. Copyright © 2013 John Wiley & Sons, Ltd.
Block copolymers prepared by polymeric radical addition cross‐coupling reaction to different double bonds
Authors: Zhang Chengyu , Wang Qi
Published: April 2013

We present an efficient method for synthesis of block copolymer by radical addition cross‐coupling reaction between two different polymeric radicals and different double bonds. Two different monobromo polymers (P1‐Br and P2‐Br) were reacted with Cu(0)/N,N,N′,N″,N″‐pentamethyldiethylenetriamine in the presence of ethyl dithiobenzoate or 1,1‐diphenylethylene (X) and the block copolymer (P1‐X‐P2) can be obtained with high efficiency, which cannot be prepared by normal atom transfer radical coupling of mixture of P1‐Br and P2‐Br. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2817–2823.
Thermoresponsive gels based on ABA triblock copolymers: Does the asymmetry matter?
Authors: Ward Mark A. , Georgiou Theoni K.
Published: April 2013

The aim of this study was to investigate the effect of the asymmetry of the triblock copolymers on their thermoresponsive self‐assembly behavior. To this end, nine ABA‐type triblock copolymers with n‐butyl methacrylate and 2‐(dimethylamino)ethyl methacrylate (DMAEMA) consisting of the A and the B blocks, respectively, were synthesized. Polymers of three different DMAEMA contents (50, 60, and 70 wt %) were synthesized while varying the length ratio of the two hydrophobic A blocks. Specifically, one symmetric ABA triblock copolymer and two asymmetric ABA′ triblock copolymers with the length of the second A block to be twice or four times bigger than the length of the first A block (AB2A and AB4A triblock copolymer) were synthesized for each DMAEMA composition. Three statistical copolymers were also synthesized for comparison. The thermoresponsive behavior of the copolymers was studied and it was found that the cloud point and rheological properties of the polymers were strongly affected by the architecture (statistical vs. block) and less strongly by the DMAEMA composition and the asymmetry of the polymers. Nevertheless, interestingly the asymmetry of the ABA triblock copolymers did influence the thermoresponsive behavior with the more symmetric polymers presenting a sol–gel transition at lower temperatures. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2850–2859.
A method for processing multivariate data in medical studies
Authors: Coubard Olivier A.
Published: April 2013

Traditional displays of principal component analyses lack readability to discriminate between putative clusters of variables or cases. Here, the author proposes a method that clusterizes and visualizes variables or cases through principal component analyses thus facilitating their analysis. The method displays pre‐determined clusters of variables or cases as urchins that each has a soma (the average point) and spines (the individual variables or cases). Through three examples in the field of neuropsychology, the author illustrates how urchins help examine the modularity of cognitive tasks on the one hand and identify groups of healthy versus brain‐damaged participants on the other hand. Some of the data used in this article were obtained from the Alzheimer's Disease Neuroimaging Initiative database. The urchin method was implemented in MATLAB, and the source code is available in the Supporting information. Urchins can be useful in biomedical studies to identify distinct phenomena at first glance, each having several measures (clusters of variables) or distinct groups of participants (clusters of cases). Copyright © 2013 John Wiley & Sons, Ltd.
Lyapunov exponent and bifurcation characteristics in synchronous machines with an internal fault
Authors: Shariatmadar Seyed Mohammad , Nazarzadeh Jalal , Abedi Mehrdad
Published: April 2013

In this paper, first, turn‐to‐turn fault in a synchronous machine stator winding is investigated, and its inductances are derived with the winding function method. Then, using the nonlinear control theory, the first‐order Poincaré map of the synchronous machine is computed, and a new extended Poincaré map of the machine is established. Also, the characteristic multipliers of the synchronous machine are calculated by the Poincaré map. This new map is capable of analyzing electrical machines in the nonlinear and unbalanced cases for evaluation of stability, bifurcation, and chaos phenomena. The results show that the new map is an effective technique for modeling and analyzing any AC electrical machines. The characteristic multipliers and the Lyapunov exponents of the extended map indicate the system's condition. Chaotic phenomena are observed in some machines with internal faults. Since chaotic systems have a continuous spectrum and various kinds of frequencies in their spectrum, identification of the internal fault location is not easy with harmonic analyses such as Fourier spectrum method on the excitation current in synchronous machines. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Experiment of an electric water heater with autonomous frequency regulation
Authors: Kondoh Junji
Published: April 2013

Integration of wind power generation into power systems has been limited because of the problem of frequency regulation during light‐load periods at night in some areas in Japan. As a solution, autonomous frequency regulation by electric water heaters (EWHs) has been proposed. A control board to control the power consumption of an EWH is fabricated. It measures both the power system frequency and thermal energy stored in a hot‐water tank, and then turns on/off a heating element according to a control algorithm. It is confirmed that the board can measure power system frequency every 1 s with a resolution of better than 0.01 Hz and that it can measure the vertical temperature distribution in the storage tank with an acceptable accuracy to calculate the future power consumption ratio, which is a parameter that decides the turn on/off of the heating element while considering end‐user comfort. Then, an EWH with autonomous frequency regulation is fabricated by embedding the board, and the EWH is operated to investigate the performance. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Sediment discharge division at two tidally influenced river bifurcations
Authors: Sassi M. G. , Hoitink A. J. F. , Vermeulen B. , Hidayat H.
Published: April 2013

Key Points

Bed‐load and suspended‐load division functions at bifurcations are different

3D effects of the suspended sediment transport at bifurcations can be limited

Sediment transport rates can be estimated from boat‐mounted ADCPs
How runoff begins (and ends): Characterizing hydrologic response at the catchment scale
Authors: Mirus Benjamin B. , Loague Keith
Published: April 2013

Key Points

Development of a quantitative Dunne diagram is presented

Relative rates of infiltration versus lateral drainage controls runoff

Unsaturated storage dynamics are critical for evaluating runoff
How changes in fibril‐level organization correlate with the macrolevel behavior of articular cartilage
Authors: Nickien Mieke , Thambyah Ashvin , Broom Neil
Published: April 2013

The primary structural components of articular cartilage are the zonally differentiated interconnected network of collagen fibrils and proteoglycans, the latter having the potential to bind large amounts of water. Both components exist in a coupled relationship that gives rise to its remarkable mechanical properties. The response of cartilage to compression is governed both by the degree to which the hydrated proteoglycans are constrained within this fibrillar network and the ease with which the matrix fluid can be displaced. The functional properties of cartilage are therefore closely linked to the integrity of the fibrillar network. Our current understanding of this network has been derived via studies conducted at the macro, micro, and ultrastructural levels. Of particular interest to joint researchers and clinicians are issues relating to how the network structure varies both directionally and with zonal depth, how its integrity is maintained via mechanisms of fibril interconnectivity, and how it is modified by ageing, degeneration, and trauma. Physical models have been developed to explore modes of interconnectivity. Combined micromechanical and structural studies confirm the critical role that this interconnectivity must play but detailed descriptions at the molecular level remain elusive. Current computationally based models of cartilage have in some cases implemented the fibrillar component, albeit simplistically, as a separate structure. Considering how important a role fibril network interconnectivity plays in actual tissue structure and mechanical behavior, and especially how it changes with degeneration, a major challenge facing joint tissue modellers is how to incorporate such a feature in their models. WIREs Syst Biol Med 2013, 5:495–509. doi: 10.1002/wsbm.1220

This article is categorized under:

Models of Systems Properties and Processes > Organ, Tissue, and Physiological Models
Adequacy of Lymph Node Retrieval for Ampullary Cancer and Its Association with Improved Staging and Survival
Authors: Partelli Stefano , Crippa Stefano , Capelli Paola , Neri Anna , Bassi Claudio , Zamboni Giuseppe , Barugola Giuliano , Falconi Massimo
Published: April 2013

Background

The aim of the present study was to determine the optimal number of lymph nodes (LN) examined to stage pN0 tumors after surgery for ampulla of Vater carcinoma (AVC).

Methods

We reviewed retrospectively 127 patients with AVC who underwent pancreaticoduodenectomy (1990–2008). Univariate and multivariate analysis was performed.

Results

Fifty‐nine patients (46.5 %) were pN0, whereas 68 patients (53.5 %) were pN1. The 5‐year disease‐specific survival (DSS) was worse for pN1 patients than for pN0 patients (46 vs. 77 %; P < 0.0001). In the pN0 cohort, the optimal cut‐off number of LN analyzed was found to be 12. The 5‐year DSS for patients with ≤12 LN was 50 %, compared with 89 % in those with >12 LN (P = 0.001). By multivariate analysis, a LN count >12 was the only independent predictor associated with improved survival (HR 0.16, P = 0.003) among pN0 patients. Among pN1 patients, a LN count >12 was associated with a significantly better 5‐year DSS (59 vs. 22 %; P = 0.027). Patients with a lymph node ratio (LNR) >0.20 had a 5‐year DSS of 24 %, compared with 58 % in those with 0 < LNR ≤ 0.20 (P = 0.038).

Conclusions

Removal of more than 12 LN for examination is associated with improved survival rate after surgery for AVC in both pN0 and pN1 patients.
Small High‐Density Lipoprotein (HDL) Subclasses are Increased with Decreased Activity of HDL‐Associated Phospholipase A2 in Subjects with Prediabetes
Authors: Filippatos Theodosios D. , Rizos Evangelos C. , Tsimihodimos Vasilios , Gazi Irene F. , Tselepis Alexandros D. , Elisaf Moses S.
Published: April 2013

Alterations in high‐density lipoprotein (HDL) subclass distribution, as well as in the activities of HDL‐associated enzymes, have been associated with increased cardiovascular disease (CVD) risk. HDL subclass distribution and the activities of HDL‐associated enzymes remain unknown in prediabetic patients, a condition also associated with increased CVD risk. The aim of the present study was to assess any differences in HDL subclass distribution (using polyacrylamide gel electrophoresis) and in activities of HDL‐associated enzymes between prediabetic (impaired fasting glucose, IFG, n = 80) and non‐prediabetic subjects (n = 105). Subjects with prediabetes had significantly increased waist circumference, blood pressure and triacylglycerol (TAG) levels compared with subjects with fasting glucose levels <100 mg/dL (all p < 0.05). The proportion of small HDL3 over HDL cholesterol (HDL‐C) was significantly increased in prediabetic subjects compared with their controls (p < 0.05). The activity of the anti‐atherogenic HDL‐associated lipoprotein‐associated phospholipase A2 (HDL‐LpPLA2) was significantly lower in subjects with prediabetes (p < 0.05), whereas the activity of paraoxonase 1 (using both paraoxon and phenyl acetate as substrates) did not significantly differ between subjects with or without prediabetes. In a stepwise linear regression analysis, the proportion of small HDL3 over HDL‐C concentration was independently associated with the presence of prediabetes and with total cholesterol and TAG concentration (positively), as well as with HDL‐C levels (negatively). We also observed a trend of increased small dense low‐density lipoprotein cholesterol levels in prediabetic subjects compared with their controls. Subjects with IFG exhibit increased proportion of small HDL3 particles combined with decreased activity of the anti‐atherogenic HDL‐LpPLA2.
PDE5-Is for the Treatment of Concomitant ED and LUTS/BPH
Authors: Gacci M. , Sebastianelli A. , Salvi M. , Vignozzi L. , Corona G. , McVary K. T. , Kaplan S. A. , Oelke M. , Maggi M. , Carini M.
Published: April 2013

Epidemiologic data in adult men exhibit a strong relationship between erectile dysfunction (ED) and lower urinary tract symptoms suggestive of benign prostatic hyperplasia (LUTS/BPH), indicating that men affected by ED should also be investigated for LUTS/BPH and those presenting with storage or voiding LUTS should be investigated for co-morbid ED. Common pathophysiolgical mechanisms underlying both LUTS/BPH and ED, including alteration of NO/cGMP or RhoA/Rho-kinase signaling and/or vascular or neurogenic dysfunction, are potential targets for proposed phosphodiesterase type 5 inhibitors (PDE5-Is). Several randomized controlled trials and only a few reviews including all commercially available PDE5-Is demonstrated the safety and efficacy of these drugs in the improvement of erectile function and urinary symptoms, in patients affected either by ED, LUTS, or both conditions.
Terahertz and optical study of monolayer graphene processed by plasma oxidation
Authors: Choi Kyujin , Lim Juhwan , Rani J. R. , Seo Yoon Hyong , Oh Juyeong , Hong Taeyoon , Ha Taewoo , Cheol Park Byung , Ik Sim Kyung , Chan Jun Seong , Hoon Kim Jae
Published: April 2013

We report on our terahertz and optical study of monolayer graphene grown by chemical vapor deposition and processed by plasma oxidation. The plasma oxidation induces oxygen-related defects, and the resulting disorder increases the sheet resistance of graphene as measured via terahertz spectroscopy. The excitonic absorption peak weakens considerably and blue shifts upon plasma oxidation, resulting in higher transmittance in both the visible and ultraviolet regions. Our oxygen plasma-treated graphene also exhibits a free-carrier doping effect as confirmed by the blue shift of the Raman G band.
Direct imaging of hot spots in Bi2Sr2CaCu2O8+δ mesa terahertz sources
Authors: Benseman T. M. , Koshelev A. E. , Kwok W.-K. , Welp U. , Vlasko-Vlasov V. K. , Kadowaki K. , Minami H. , Watanabe C.
Published: April 2013

Stacks of intrinsic Josephson junctions (IJJs) made from high-temperature superconductors such as Bi2Sr2CaCu2O8+δ (Bi-2212) (BSCCO) are a promising source of coherent continuous-wave terahertz radiation. It is thought that at electrical bias conditions under which THz-emission occurs, hot spots may form due to resistive self-heating, and that these spots may be highly beneficial for the generation of high levels of THz power. Here, we perform an imaging study of the temperature distribution at the surface of BSCCO stacks utilizing the temperature-dependent 612 nm fluorescence line of Eu3+ in a europium chelate. The images directly reveal a highly non-uniform temperature distribution in which the temperature in the middle of the stack can exceed the superconducting transition temperature by tens of Kelvin under biasing conditions typical for THz-emission.
Accurate ab initio potential energy surface, thermochemistry, and dynamics of the Br(2P, 2P3/2) + CH4 → HBr + CH3 reaction
Authors: Czakó Gábor
Published: April 2013

Chemically accurate full-dimensional non-spin-orbit and spin-orbit (SO) ground-state potential energy surfaces (PESs) are obtained for the Br + CH4 → HBr + CH3 reaction by fitting 21 574 composite ab initio energy points. The composite method considers electron correlation methods up to CCSD(T), basis sets up to aug-cc-pwCVTZ-PP, correlation of the core electrons, scalar relativistic effects via an effective core potential (ECP), and SO corrections, thereby achieving an accuracy better than 0.5 kcal/mol. Benchmark structures and relative energies are computed for the stationary points using the ab initio focal-point analysis (FPA) scheme based on both ECP and Douglas−Kroll approaches providing all-electron relativistic CCSDT(Q)/complete-basis-set quality energies. The PESs accurately describe the saddle point of the abstraction reaction and the van der Waals complexes in the entrance and product channels. The SO-corrected PES provides a classical barrier height of 7285(7232 ± 50) cm−1, De values of 867(799 ± 10) and 399(344 ± 10) cm−1 for the complexes CH3–HBr and CH3–BrH, respectively, and reaction endothermicity of 7867(7857 ± 50) cm−1, in excellent agreement with the new, FPA-based benchmark data shown in parentheses. The difference between the Br + CH4 asymptotes of the non-SO and SO PESs is 1240 cm−1, in good agreement with the experiment (1228 cm−1). Quasiclassical trajectory calculations based on more than 13 million trajectories for the late-barrier Br + CH4(vk = 0, 1) [k = 1, 2, 3, 4] reactions show that the vibrational energy, especially the excitation of the stretching modes, activates the reaction much more efficiently than translational energy, in agreement with the extended Polanyi rules. Angular distributions show dominant backward scattering for the ground-state reaction and forward scattering for the stretching-excited reactions. The reactivity on the non-SO PES is about 3−5 times larger than that on the SO PES in a wide collision energy range of 8000−16 000 cm−1.
Out-of-equilibrium catalysis of chemical reactions by electronic tunnel currents
Authors: Dzhioev Alan A. , Kosov Daniel S. , von Oppen Felix
Published: April 2013

We present an escape rate theory for current-induced chemical reactions. We use Keldysh nonequilibrium Green's functions to derive a Langevin equation for the reaction coordinate. Due to the out of equilibrium electronic degrees of freedom, the friction, noise, and effective temperature in the Langevin equation depend locally on the reaction coordinate. As an example, we consider the dissociation of diatomic molecules induced by the electronic current from a scanning tunnelling microscope tip. In the resonant tunnelling regime, the molecular dissociation involves two processes which are intricately interconnected: a modification of the potential energy barrier and heating of the molecule. The decrease of the molecular barrier (i.e., the current induced catalytic reduction of the barrier) accompanied by the appearance of the effective, reaction-coordinate-dependent temperature is an alternative mechanism for current-induced chemical reactions, which is distinctly different from the usual paradigm of pumping vibrational degrees of freedom.
Body-fixed relativistic molecular Hamiltonian and its application to nuclear spin-rotation tensor
Authors: Xiao Yunlong , Liu Wenjian
Published: April 2013

A relativistic molecular Hamiltonian that describes electrons fully relativistically and nuclei quasi-relativistically is proposed and transformed from the laboratory to the body-fixed frame of reference. As a first application of the resulting body-fixed relativistic molecular Hamiltonian, the long anticipated relativistic theory of nuclear spin-rotation (NSR) tensor is formulated rigorously. A “relativistic mapping” between experimental NSR and NMR is further proposed, which is of great value in establishing high-precision absolute NMR shielding scales.
Evaporation-induced saline Rayleigh convection inside a colloidal droplet
Authors: Kang Kwan Hyoung , Lim Hee Chang , Lee Hee Woong , Lee Sang Joon
Published: April 2013

Inside evaporating two-component sessile droplets, a family of the Rayleigh convection exists, driven by salinity gradient formed by evaporation of solvent and solute. In this work, the characteristic of the flow inside an axisymmetric droplet is investigated. A stretched coordinate system is employed to account for the effect of boundary movement. A scaling analysis shows that the flow velocity is proportional to the (salinity) Rayleigh number (Ras) at the small-Rayleigh-number limit. A numerical analysis for a hemispherical droplet exhibits the flow velocity is proportional to the non-dimensional number \documentclass[12pt]{minimal}\begin{document}$Ra_s^{1/2}$\end{document}Ras1/2, at high Rayleigh numbers. A self-similar condition is established for the concentration field irrespective of the Rayleigh numbers after a moderate time, and the flow field is invariant with time at this stage. The scaling relation for the high Rayleigh numbers is verified experimentally by using aqueous NaCl droplets.
Modified Z method to calculate melting curve by molecular dynamics
Authors: Wang Shuaichuang , Zhang Gongmu , Liu Haifeng , Song Haifeng
Published: April 2013

We extend the recently proposed Z method of estimating the melting temperature from a complete liquid and propose a modified Z method to calculate the melting temperature from a solid-liquid coexistence state. With the simulation box of rectangular parallelepiped, an initial structure of perfect lattice can run in the microcanonical ensemble to achieve steady solid-liquid coexistence state. The melting pressure and temperature are estimated from the coexistence state. For the small system with 1280 atoms, the simulation results show that the melting curve of copper has a good agreement with the experiments and is identical in accuracy with the results of the two-phase coexistence method with 24 000 atoms in the literature. Moreover, the method is conceptually simpler than the two-phase coexistence method.
Lipschitz stability criteria for functional differential systems of fractional order
Authors: Stamova Ivanka , Stamov Gani
Published: April 2013

In this paper, a class of fractional functional differential equations is investigated. Using differential inequalities and Lyapunov-like functions, Lipschitz stability, uniform Lipschitz stability, and global uniform Lipschitz stability criteria are proved. Since the problem of Lipschitz stability of dynamic systems is relevant in various contexts, including many inverse and control problem, our results can be applied in the qualitative investigations of many practical problems of diverse interest.
A climbing string method for saddle point search
Authors: Ren Weiqing , Vanden-Eijnden Eric
Published: April 2013

The string method originally proposed for the computation of minimum energy paths (MEPs) is modified to find saddle points around a given minimum on a potential energy landscape using the location of this minimum as only input. In the modified method the string is evolved by gradient flow in path space, with one of its end points fixed at the minimum and the other end point (the climbing image) evolving towards a saddle point according to a modified potential force in which the component of the potential force in the tangent direction of the string is reversed. The use of a string allows us to monitor the evolution of the climbing image and prevent its escape from the basin of attraction of the minimum. This guarantees that the string always converges towards a MEP connecting the minimum to a saddle point lying on the boundary of the basin of attraction of this minimum. The convergence of the climbing image to the saddle point can also be accelerated by an inexact Newton method in the late stage of the computation. The performance of the numerical method is illustrated using the example of a 7-atom cluster on a substrate. Comparison is made with the dimer method.