Scaled laboratory experiments explain the kink behaviour of the Crab Nebula jet

The remarkable discovery by the Chandra X-ray observatory that the Crab nebula's jet periodically changes direction provides a challenge to our understanding of astrophysical jet dynamics. It has been suggested that this phenomenon may be the consequence of magnetic fields and magnetohydrodynamic instabilities, but experimental demonstration in a controlled laboratory environment has remained elusive. Here we report experiments that use high-power lasers to create a plasma jet that can be directly compared with the Crab jet through well-defined physical scaling laws. The jet generates its own embedded toroidal magnetic fields; as it moves, plasma instabilities result in multiple deflections of the propagation direction, mimicking the kink behaviour of the Crab jet. The experiment is modelled with three-dimensional numerical simulations that show exactly how the instability develops and results in changes of direction of the jet.

The periodical change of the Crab nebula's jet direction challenges our understanding of astrophysical jet dynamics. Here the authors use high-power lasers to create a jet that can be directly compared to the Crab nebula's, and report the detection of plasma instabilities that mimic kink behaviour.

Atypia of undetermined significance on thyroid fine needle aspiration - risk factors for malignancy

OBJECTIVES

This study is designed to determine the clinical predictors of malignancy in the atypia of undetermined significance (AUS) category resulted from thyroid fine needle aspiration (FNA).

DESIGN

Retrospective cohort study.

SETTING

Dong-A University Medical Center, Busan, Korea.

PARTICIPANTS

Sixty-two patients who underwent thyroid surgery from January 2010 to December 2013, following a diagnosis of AUS from preoperative thyroid FNA.

MAIN OUTCOME MEASURES

We investigated the age, gender, maximum size and site of the nodules, ultrasonographic findings, cytological features, BRAF gene mutation, surgical method, number of AUS on repeated FNA and final pathologic results.

RESULTS

Forty-one of sixty-two patients underwent total thyroidectomy and the rest had lobectomy. The final pathologic results were 41 malignancies and 21 benign diseases. Nodules less than 1.5 cm, ultrasonographic findings suggestive of malignancy were risk factors for malignancy on univariated analysis (P < 0.001). Multivariated analysis showed that nodules less than 1.5 cm, ultrasonographic findings suggestive of malignancy and more than 2 results of atypia from repeated FNAs were significant risk factors for malignancy (P < 0.001). A BRAF gene mutation analysis was performed in 38 patients, and 13 patients had the mutation. All patients with the BRAF gene mutation had been diagnosed with papillary thyroid cancer (P > 0.05).

CONCLUSIONS

We recommend close observation or diagnostic surgery in patients with nodules <1.5 cm and with two or more malignant ultrasound feature and a BRAF mutation, or with two or more AUS findings on repeated FNAs.

Cartilage-inspired superelastic ultradurable graphene aerogels prepared by the selective gluing of intersheet joints

In this study, we demonstrate a cartilage-inspired superelastic and ultradurable nanocomposite strategy for the selective inclusion of viscoelastic poly(dimethylsiloxane) (PDMS) into graphene sheet junctions to create effective stress-transfer pathways within three-dimensional (3D) graphene aerogels (GAs). Inspired by the joint architectures in the human body, where small amounts of soft cartilage connect stiff (or hard) but hollow (and thus lightweight) bones, the 3D internetworked GA@PDMS achieves synergistic toughening. The resulting GA@PDMS nanocomposites exhibit fully reversible structural deformations (99.8% recovery even at a 90% compressive strain) and high compressive mechanical strength (448.2 kPa at a compressive strain of 90%) at repeated compression cycles. Owing to the combination of excellent mechanical and electrical properties, the GA@PDMS nanocomposites are used as signal transducers for strain sensors, showing very short response and recovery times (in the millisecond range) with reliable sensitivity and extreme durability. Furthermore, the proposed system is applied to electronic scales with a large detectable weight of about 4600 times greater than its own weight. Such bio-inspired cartilage architecture opens the door to fabricate new 3D multifunctional and mechanically durable nanocomposites for emerging applications, which include sensors, actuators, and flexible devices.

Correction: Cartilage-inspired superelastic ultradurable graphene aerogels prepared by the selective gluing of intersheet joints

Correction for 'Cartilage-inspired superelastic ultradurable graphene aerogels prepared by the selective gluing of intersheet joints' by Jin-Yong Hong, et al., Nanoscale, 2016, DOI: 10.1039/c6nr01986b.

Treatment Strategy for Persistent Sciatic Artery and Novel Classification Reflecting Anatomic Status

BACKGROUND

Persistent sciatic artery (PSA) is a relatively rare congenital variant of the lower limb vasculature and can have highly variable clinical presentations. The purpose of this study was to analyze the relationship between PSA anatomy and clinical presentation, and to suggest an optimal management strategy.

METHODS

Between 2001 and 2014, 24 PSAs in 19 patients were diagnosed by computed tomography and referred to the vascular surgery department. Patient demographics, types of PSA and femoral artery, aneurysmal changes, symptoms, and treatment methods were assessed. Additionally, all English literature from 1964 to 2014 was reviewed and compared using the PubMed database (224 PSAs in 171 patients).

RESULTS

PSA was diagnosed in 10 men (52.6%) and nine women (47.4%). PSAs were bilateral in five patients (26.3%) and symptomatic in 12 patients, while in seven patients PSA was found incidentally. According to the Pillet-Gauffre classification, Type 2a was the most common variant (n = 15/24, 62.5%), with unclassifiable types in two limbs. Compared with cases in the literature, the PSA occlusion rate in this study was higher (n = 10/24, 41.7% vs. n = 54/224, 27.5%), but aneurysm incidence was higher in the literature cases (n = 5/24, 20.8% vs. n = 112/224; 50.7%). In this study, 16 limbs (66.6%) were treated conservatively, and six limbs were treated by open surgery, including four bypasses, one amputation, and one thrombo-embolectomy. Endovascular coil embolization was performed in one limb, and a hybrid procedure with stent graft was performed in one limb with PSA aneurysm. Based on the present series and the literature review, a new classification system and treatment option is proposed according to the anatomic status and the presence of aneurysm. According to the new classification, class III was the most common in both the present study (18/24; 75%) and the literature review, and the presence of aneurysm was the most important determinant of surgical treatment.

CONCLUSIONS

The new classification system is simple and provides guidance for management. Limb anatomy of the femoral artery system and the presence of PSA aneurysm should be considered when selecting the optimal treatment. The risk of embolism from the presence of aneurysm is an important factor for treatment, and bypass surgery is mostly required in classes III and IV.

Relationship between underweight, bone mineral density and skeletal muscle index in premenopausal Korean women

AIM

Osteoporosis and sarcopenia are common health problems in postmenopausal women. However, studies of these issues in premenopausal women are limited. Our present study aimed to investigate relationship the between underweight, bone mineral density (BMD) and skeletal muscle index (SMI) in a representative sample of premenopausal Korean women.

METHODS

We used data from the Korea National Health and Nutrition Examination Surveys (2009-2010). Participants included 1767 healthy, ≥ 20-year-old, non-obese premenopausal women. Underweight was defined as BMI< 18.5 kg/m(2) and normal weight was defined as 18.5 ≤ BMI< 23 kg/m(2) . We analysed anthropometric measurements, BMD and SMI with a DXA scanner. Multiple logistic regression analysis was performed to assess the relationship between underweight, BMD and SMI after adjusting for confounding factors.

RESULTS

The prevalence of low BMD and low SMI in underweight women was 23.9% and 18.4%, respectively, compared with 9.4% and 1.7% in normal weight women. Low BMD and/or low SMI were present in 36.7% of underweight women compared with 10.7% of normal weight women. After adjustments, underweight women exhibited a higher odds ratio for low BMD (OR, 3.41; 95% CI, 2.31-5.05), low SMI (OR, 11.61; 95% CI, 6.17-21.88) and combined low BMD and low SMI (OR, 23.82; 95% CI, 8.92-63.58) when compared with normal weight women.

CONCLUSION

Underweight premenopausal women are at a higher risk of low bone mass and low skeletal muscle. Educational efforts that promote a normal weight in premenopausal women should be reinforced.

Trends in type 2 diabetes prevalence according to income levels in Korea (1998-2012)

There was no significant association between diabetes prevalence and income levels for either sex in 1998. However, the high income level in men and the low income level in women positively related to the odds of diabetes in 2011-2012. Preventive strategies for diabetes should consider the gender-specific economic discrepancy.

Spontaneous Polarization and Bulk Photovoltaic Effect Driven by Polar Discontinuity in LaFeO_{3}/SrTiO_{3} Heterojunctions

Structurally coherent and chemically abrupt interfaces formed between polar and nonpolar perovskite oxides provide an ideal platform for examining the purely electronic reconstruction known as the polar catastrophe and the emergence of mobile or bound charges at the interface. The appearance of mobile charges induced by the polar catastrophe is already established in the LaAlO_{3}/SrTiO_{3} heterojunctions. Although not experimentally verified, the polar catastrophe can also lead to the emergence of spontaneous polarization. We report that thin films of originally nonpolar LaFeO_{3} grown on SrTiO_{3} are converted to polar as a consequence of the polar catastrophe. The induced spontaneous polarization evokes photovoltaic properties distinct from conventional p-n junctions, such as a switching of the photocurrent direction by changing the interfacial atomic sequence. The control of the bulk polarization by engineering the interface demonstrated here will expand the possibilities for designing and realizing new polar materials with photovoltaic functions.

Abstract P1-15-04: Irriversible chemotherapy-induced alopecia in breast cancer patient

Introduction

Patients with breast cancer who received chemotherapy have distressing side effects such as mucositis, alopecia, gastritis, and BM suppression. Chemotherapy-induced alopecia(CIA) is one of considerable psychological events in self-esteem in patients with breast cancer, but the possibility of irreversible alopecia is often overlooked by physician.

We investigated clinical characteristics of CIA and prevalence of irreversible severe hair loss in patient with breast cancer who received chemotherapy.

Methods

We conducted a survey to collect demographic information about CIA with 150 breast cancer patients who had passed at least 6 months since their last day of chemotherapy from February 2015 to May 2015 in Yonsei Cancer Center. We obtained clinical information as age, elapsed time from end of chemotherapy, chemotherapy regimen, and other adjuvant therapy using their electrical medical records. We compared irreversible CIA characters between anthracycline and cyclophosphamide (AC) and taxane based regimen groups. The severe alopecia was defined as the hair density loss over 50% compared to the hair density before chemotherapy.

Results

The mean age at chemotherapy was 48 years old (±17.3) and the mean elapsed time after chemotherapy was 37 months (±9.5) in total patients.

Remnant alopecia was reported in 71 patients (47.3%). Wig or hat were used in 39 patients (26.0%).

The mean satisfaction score with a five-point scale was 4 in patients without alopecia or hair character change and 2.2 in patients with irreversible alopecia (p&lt;0.001). The severe irreversible hair loss was complained by the 12 (8.2%) patients.

AC and taxane based chemotherapy were carried out in 65 and 85 patients, respectively. In AC group, remnant alopecia was shown in 18 patients (27.7%), and more than a half of patients in taxane group, 53 patients (62.4%), showed remnant alopecia (p&lt;0.001). While only five patients (7.8%) in AC group suffered for severe hair loss, 26 patients (31.3%) in taxane group were affected by severe hair loss (p=0.001). The mean satisfaction level of hair status in patients in taxane group was 2.5 as compared to 3.6 in those in AC group (p&lt;0.001).

Conclusion

Contrary to general expectation, About a half of breast cancer patients who received chemotherapy complained of irreversible hair loss even though at least 6 months has elapsed since the end of chemotherpy. In particular, patients with taxane based chemotherapy had more irreversible and severe alopecia than those with AC chemotherapy.

Citation Format: Kim S, Park HS, Kim JY, Nam S, Kim GM, Sohn JH, Kim SI. Irriversible chemotherapy-induced alopecia in breast cancer patient. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-15-04.

Phylogenetic group distributions, virulence factors and antimicrobial resistance properties of uropathogenic Escherichia coli strains isolated from patients with urinary tract infections in South Korea

Urinary tract infections (UTIs) are one of the most common diseases by which humans seek medical help and are caused mainly by uropathogenic Escherichia coli (UPEC). Studying the virulence and antibiotic resistance of UPEC with respect to various phylogenetic groups is of utmost importance in developing new therapeutic agents. Thus, in this study, we analysed the virulence factors, antibiotic resistance and phylogenetic groups among various UPEC isolates from children with UTIs. The phylogenetic analysis revealed that majority of the strains responsible for UTIs belonged to the phylogenetic groups B2 and D. Of the 58 E. coli isolates, 79·31% belonged to group B2, 15·51% to group D, 3·44% to group A and 1·72% to B1. Simultaneously, the number of virulence factors and antibiotic resistance exhibited were also significantly high in groups B2 and D compared to other groups. Among the isolates, 44·8% were multidrug resistant and of that 73% belonged to the phylogenetic group B2, indicating the compatibility of antibiotic resistance and certain strains carrying virulence factor genes. The antibiotic resistance profiling of UPEC strains elucidates that the antimicrobial agents such as chloramphenicol, cefoxitin, cefepime, ceftazidime might still be used in the therapy for treating UTIs.

SIGNIFICANCE AND IMPACT OF THE STUDY

As the antibiotic resistance pattern of uropathogenic Escherichia coli varies depending on different geographical regions, the antibiotic resistance pattern from this study will help the physicians to effectively administer antibiotic therapy for urinary tract infections. In addition, the frequency of virulence factors and antibiotic resistance genes among various phylogenic groups could be effectively used to draw new targets for uropathogenic Escherichia coli antibiotic-independent therapies. The study emphasizes need of public awareness on multidrug resistance and for more prudent use of antimicrobials.

MACVIA-ARIA Sentinel NetworK for allergic rhinitis (MASK-rhinitis): the new generation guideline implementation

Several unmet needs have been identified in allergic rhinitis: identification of the time of onset of the pollen season, optimal control of rhinitis and comorbidities, patient stratification, multidisciplinary team for integrated care pathways, innovation in clinical trials and, above all, patient empowerment. MASK-rhinitis (MACVIA-ARIA Sentinel NetworK for allergic rhinitis) is a simple system centred around the patient which was devised to fill many of these gaps using Information and Communications Technology (ICT) tools and a clinical decision support system (CDSS) based on the most widely used guideline in allergic rhinitis and its asthma comorbidity (ARIA 2015 revision). It is one of the implementation systems of Action Plan B3 of the European Innovation Partnership on Active and Healthy Ageing (EIP on AHA). Three tools are used for the electronic monitoring of allergic diseases: a cell phone-based daily visual analogue scale (VAS) assessment of disease control, CARAT (Control of Allergic Rhinitis and Asthma Test) and e-Allergy screening (premedical system of early diagnosis of allergy and asthma based on online tools). These tools are combined with a clinical decision support system (CDSS) and are available in many languages. An e-CRF and an e-learning tool complete MASK. MASK is flexible and other tools can be added. It appears to be an advanced, global and integrated ICT answer for many unmet needs in allergic diseases which will improve policies and standards.

Segmentation and surface reconstruction of a cadaver heart on Mimics software

The Visible Korean research team used Mimics software (Materialise, Leuven, Belgium) for the segmentation and subsequent surface reconstruction of heart structures using information obtained from sectioned images of a cadaver. Twenty-six heart components were outlined in advance on Photoshop (Adobe Systems, San Jose, CA, USA). By use of the Mimics, the outlined images were then browsed along with the vertical planes as well as the 3-dimensional surface models, which were immediately built by piling the images. Erroneous delineation was readily detected and revised until satisfactory heart models were acquired. The surface models and the selected sectioned images in horizontal, coronal, and sagittal planes were inputted into a PDF file, where any combinations of reconstructed constituents could be displayed and rotated by the user. Mimics software accelerated the segmentation and surface reconstruction of heart anatomical structures. Similar benefits hopefully result from various serial images of other organs. The PDF file, and plane and stereoscopic image data are being distributed to others, and should prove valuable for medical students and clinicians.

Extremely Durable, Flexible Supercapacitors with Greatly Improved Performance at High Temperatures

The reliability and durability of energy storage devices are as important as their essential characteristics (e.g., energy and power density) for stable power output and long lifespan and thus much more crucial under harsh conditions. However, energy storage under extreme conditions is still a big challenge because of unavoidable performance decays and the inevitable damage of components. Here, we report high-temperature operating, flexible supercapacitors (f-SCs) that can provide reliable power output and extreme durability under severe electrochemical, mechanical, and thermal conditions. The outstanding capacitive features (e.g., ∼40% enhancement of the rate capability and a maximum capacitances of 170 F g(-1) and 18.7 mF cm(-2) at 160 °C) are attributed to facilitated ion transport at elevated temperatures. Under high-temperature operation and/or a flexibility test in both static and dynamic modes at elevated temperatures >100 °C, the f-SCs showed extreme long-term stability of 100000 cycles (>93% of initial capacitance value) and mechanical durability after hundreds of bending cycles (at bend angles of 60-180°). Even at 120 °C, the versatile design of tandem serial and parallel f-SCs was demonstrated to provide both desirable energy and power requirements at high temperatures.

Large anisotropic deformation of skyrmions in strained crystal

Mechanical control of magnetism is an important and promising approach in spintronics. To date, strain control has mostly been demonstrated in ferromagnetic structures by exploiting a change in magnetocrystalline anisotropy. It would be desirable to achieve large strain effects on magnetic nanostructures. Here, using in situ Lorentz transmission electron microscopy, we demonstrate that anisotropic strain as small as 0.3% in a chiral magnet of FeGe induces very large deformations in magnetic skyrmions, as well as distortions of the skyrmion crystal lattice on the order of 20%. Skyrmions are stabilized by the Dzyaloshinskii-Moriya interaction, originating from a chiral crystal structure. Our results show that the change in the modulation of the strength of this interaction is amplified by two orders of magnitude with respect to changes in the crystal lattice due to an applied strain. Our findings may provide a mechanism to achieve strain control of topological magnetic structures based on the Dzyaloshinskii-Moriya interaction.

MacroH2A1 downregulation enhances the stem-like properties of bladder cancer cells by transactivation of Lin28B

The histone variant, macroH2A1, has an important role in embryonic stem cell differentiation and tumor progression in various types of tumors. However, the regulatory roles of macroH2A1 on bladder cancer progression have not been fully elucidated. Here, we show that macroH2A1 knockdown promotes stem-like properties of bladder cancer cells. The knockdown of macroH2A1 in bladder cancer cells increased tumorigenicity, radioresistance, degeneration of reactive oxygen species, increased sphere formation capability and an increase in the proportion of side populations. We found that macroH2A1 is required for the suppression of Lin28B identified as a novel downstream target of macroH2A1 in bladder cancer. Loss of macroH2A1 expression significantly correlated with the elevated levels of Lin28B expression and subsequently inhibited the mature let-7 microRNA expression. Furthermore, the stable overexpression of Lin28B enhances the several phenotypes, including tumorigenicity and sphere-forming ability, which are induced by macroH2A1 depletion. Importantly, Lin28B expression was regulated by macroH2A1-mediated reciprocal binding of p300 and EZH2/SUV39H1. Our results suggest that Lin28B/let-7 pathway is tightly regulated by macroH2A1 and its cofactors, and have a pivotal role in the bladder tumor progression and the regulation of stem-like characteristics of bladder cancer cells.

Absorption and desorption of SO2 in aqueous solutions of diamine-based molten salts

SO2 absorption and desorption behaviors were investigated in aqueous solutions of diamine-derived molten salts with a tertiary amine group on the cation and a chloride anion, including butyl-(2-dimethylaminoethyl)-dimethylammonium chloride ([BTMEDA]Cl, pKb=8.2), 1-butyl-1,4-dimethylpiperazinium chloride ([BDMP]Cl, pKb=9.8), and 1-butyl-4-aza-1-azoniabicyclo[2,2,2]octane chloride ([BDABCO]Cl, pKb=11.1). The SO2 absorption and desorption performance of the molten salt were greatly affected by the basicity of the molten salt. Spectroscopic, X-ray crystallographic, and computational results for the interactions of SO2 with molten salts suggest that two types of SO2-containg species could be generated depending on the basicity of the unquaternized amino group: a dicationic species comprising two different anions, HSO3(-) and Cl(-), and a monocationic species bearing Cl(-) interacting with neutral H2SO3.

Manipulating the glass transition behavior of sulfonated polystyrene by functionalized nanoparticle inclusion

Nanoscale interfaces can modify the phase transition behaviors of polymeric materials. Here, we report the double glass transition temperature (Tg) behavior of sulfonated polystyrene (sPS) by the inclusion of 14 nm amine-functionalized silica (NH2-SiO2) nanoparticles, which is different from the single Tg behaviors of neat sPS and silica (SiO2)-filled sPS. The inclusion of 20 wt% NH2-SiO2 nanoparticles results in an increase of Tg by 9.3 °C as well as revealing a second Tg reduced by 44.7 °C compared to the Tg of neat sPS. By contrast, when SiO2 nanoparticles with an identical concentration and size to NH2-SiO2 are dispersed, sPS composites possess a single Tg of 7.3 °C higher than that of the neat sPS. While a nanoscale dispersion is observed for SiO2 nanoparticles, as confirmed by microscopic and X-ray scattering analyses, NH2-SiO2 nanoparticles show the coexistence of micron-scale clustering along with a nanoscale dispersion of the individual nanoparticles. The micro-phase separation contributes to the free volume induced Tg reduction by the plasticization effect, whereas the Tg increase originates from the polymer segment mobility constrained by nanoconfinement and the rigid amorphous fractions deriving from strong polymer-particle interactions.

In Vivo Tissue Pharmacokinetics of Carbon-11-Labeled Clozapine in Healthy Volunteers: A Positron Emission Tomography Study

We investigated clozapine (CLZ) tissue pharmacokinetics in vivo by using carbon-11-labeled CLZ (¹¹C-CLZ) and positron emission tomography (PET). Eight healthy volunteers underwent ¹¹C-CLZ studies wherein computed tomography image acquisition was followed by PET scans (whole-body, four; brain, four). After bolus intravenous ¹¹C-CLZ injection, PET images were acquired at various timepoints for 2–3 hours. Tissue ¹¹C-CLZ signals were plotted over time, and pharmacokinetic parameters were determined. High ¹¹C-CLZ radioactivity was detected in the liver and brain, implying CLZ hepatic metabolism and efficient blood–brain barrier penetration. The urinary and hepatobiliary tracts were involved in ¹¹C-CLZ excretion. Moderate to high radioactivity was observed in the dopaminergic and serotonergic receptor-rich brain regions, indicating CLZ binding to multiple receptor types. To our knowledge, this is the first study to report the determination of ¹¹C-CLZ tissue pharmacokinetics in humans. PET using radiolabeled drugs can provide valuable information that could complement plasma pharmacokinetic data.

Positively-charged reduced graphene oxide as an adhesion promoter for preparing a highly-stable silver nanowire film

An ultrathin conductive adhesion promoter using positively charged reduced graphene oxide (rGO-NH3(+)) has been demonstrated for preparing highly stable silver nanowire transparent conductive electrodes (AgNW TCEs). The adhesion promoter rGO-NH3(+), spray coated between the substrate and AgNWs, significantly enhances the chemical and mechanical stabilities of the AgNW TCEs. Besides, the ultrathin thickness of the rGO-NH3(+) ensures excellent optical transparency and mechanical flexibility for TCEs. The AgNW films prepared using the adhesion promoter are extremely stable under harsh conditions, including ultrasonication in a variety of solvents, 3M Scotch tape detachment test, mechanical bending up to 0.3% strain, or fatigue over 1000 cycles. The greatly enhanced adhesion force is attributed to the ionic interactions between the positively charged protonated amine groups in rGO-NH3(+) and the negatively charged hydroxo- and oxo-groups on the AgNWs. The positively charged GO-NH3(+) and commercial polycationic polymer (poly allylamine hydrochloride) are also prepared as adhesion promoters for comparison with rGO-NH3(+). Notably, the closely packed hexagonal atomic structure of rGO offers better barrier properties to water permeation and demonstrates promising utility in durable waterproof electronics. This work offers a simple method to prepare high-quality TCEs and is believed to have great potential application in flexible waterproof electronics.

Unveiling surface redox charge storage of interacting two-dimensional heteronanosheets in hierarchical architectures

Two-dimensional (2D) heteronanosheets are currently the focus of intense study due to the unique properties that emerge from the interplay between two low-dimensional nanomaterials with different properties. However, the properties and new phenomena based on the two 2D heteronanosheets interacting in a 3D hierarchical architecture have yet to be explored. Here, we unveil the surface redox charge storage mechanism of surface-exposed WS2 nanosheets assembled in a 3D hierarchical heterostructure using in situ synchrotron X-ray absorption and Raman spectroscopic methods. The surface dominating redox charge storage of WS2 is manifested in a highly reversible and ultrafast capacitive fashion due to the interaction of heteronanosheets and the 3D connectivity of the hierarchical structure. In contrast, compositionally identical 2D WS2 structures fail to provide a fast and high capacitance with different modes of lattice vibration. The distinctive surface capacitive behavior of 3D hierarchically structured heteronanosheets is associated with rapid proton accommodation into the in-plane W-S lattice (with the softening of the E2g bands), the reversible redox transition of the surface-exposed intralayers residing in the electrochemically active 1T phase of WS2 (with the reversible change in the interatomic distance and peak intensity of W-W bonds), and the change in the oxidation state during the proton insertion/deinsertion process. This proposed mechanism agrees with the dramatic improvement in the capacitive performance of the two heteronanosheets coupled in the hierarchical structure.

Factors related with metastasis of right retroesophageal lymph nodes in papillary thyroid cancer

AIM

Right retroesophageal lymph nodes (RRLNs) should be involved in central lymph nodes (CLNs) dissection in patients with papillary thyroid cancer (PTC). This study assessed the incidence and factors related to RRLNs metastasis.

METHODS

From January 2008 to March 2010, 129 patients who underwent total thyroidectomy with CLNs dissection including RRLNs were enrolled. The predictive value of RRLNs metastasis was assessed.

RESULTS

Twenty six (20.1%) of 129 patients exhibited nodal metastasis in RRLNs. Metastasis of RRLNs was associated with large tumor size (>1 cm; P<0.01), multiplicity (P=0.03), preoperative LN enlargement (P<0.01), metastasis of non-retroesophageal lateral LN (P<0.01) and large number of CLNs metastases (P<0.01) in univariate analysis. Multivariate analysis revealed that tumor size (>1 cm) and metastasis of non-retroesophageal lateral LN were independent correlates of RRLNs metastases.

CONCLUSION

RRLNs may be removed during operation for PTC, particularly in patients with tumor >1 cm and lateral LN metastases.