bluuebunny/crossref_metadata_2025 huggingface dataset:
Retirement Reconsidered: Labor Force Participation of Older Men in the United States
Authors: Falzone Joseph S.
Published: April 2016

The objectives of this article are two fold. Changes in older men’s labor force participation in the United States are first described focusing on human capital and demographic variables. A model of the labor/leisure choice and the retirement decision of older menare then estimated employing Maximum Likelihood Probit. While changes in Social Security Benefit rules are a significant factor in explaining the trend of rising retirement age among older men, the focus here is on additional factors that contribute to older men’s decision to forestall retirement. Probit coefficient estimates for three distinct age cohorts verify the effects of hypothesized determinants of the decision to retire. Specifically, the coefficient on estimated earnings is negative and hasthe largest marginal effect on the decision to retire followed by years of education and retired wife. The effects of wives’ retirement decision will likely influence and forestall the retirement decision of married men as more working women reach retirement age. The rise in labor force participation rates of older men may offset rather than reverse the decline in men’s labor force participation rates that began more than a half century ago.
Relationship between the Spiritual Intelligence, Self-Control, and Life Satisfaction in High School Teachers of Mahshahr City
Authors: Bigdeloo Masoomeh , Bozorgi Zahra Dasht
Published: April 2016

This study aims to investigate the relationship between the spiritual intelligence, self-control, and life satisfaction in high school teachers of Mahshahr city. To this end, 253 people of all high school teachers in Mahshahr city were selected as the sample using the multistage cluster sampling method. For data collection, King’s (2008) spiritual intelligence questionnaire, Schneider’s self-control questionnaire and Diener et al. (1985) life satisfaction questionnaire were used. For data analysis, Pearson’s correlation coefficient was used. Results showed that there is a positive and meaningful relationship between the self-control and life satisfaction. However, there is no a meaningful relationship between the spiritual intelligence and life satisfaction. Results also showed that spiritual intelligence and self-control can predict the life satisfaction.
Simultaneous Determination of Arsenic, Cadmium, Mercury, and Lead in Raw Ingredients, Nutritional Products, and Infant Formula by Inductively Coupled Plasma Mass Spectrometry: Single-Laboratory Validation
Authors: Pacquette Lawrence H , Anumula Anil
Published: April 2016

A method was developed for the determination of As, Cd, Hg, and Pb in raw ingredients, nutritional products, and infant formula using inductively coupled plasma mass spectrometry (ICP-MS). Three raw ingredients (acid casein, maltodextrin, skim milk powder) and three standard reference materials [NIST 1548a (Typical Diet), NIST 1577c (Bovine Liver), NIST SRM 1568b (Rice Flour)] obtained from the National Institute of Standards and Technology were analyzed by two analysts using two ICP-MS instruments in different laboratories. NIST SRM 1568b was used as the control sample. All protocol validation parameters (intermediate precision, accuracy, linearity, quantitation limit, specificity, and robustness) were met. The overall precision (n = 8) for analyte concentrations (2.5–300 ng/g) ranged from 2 to 14% RSD. Spike recoveries ranged from 88 to109% for spike levels between 25 and 200%. The overall average concentration of As, Cd, Hg, and Pb measured in all three NIST SRMs were within the certified value ranges. Good linearity (correlation coefficient (r) = 0.9995 or better) was obtained for all analytes. Control chart results for 8 independent days showed that the method is robust (precision values of 10% and all points within ±3 σ were obtained). Excellent specificity was also demonstrated when the analytes were measured in the presence of high concentrations of the other concomitants.
Practical Points in Gastric Pathology
Authors: Ahn Sangjeong , Park Do Youn
Published: April 2016

Context.—The diagnosis of gastric epithelial lesions is difficult in clinical practice, even with the recent developments and advances in endoscopic modalities, owing to the diverse morphologic features of the lesions, lack of standardized diagnostic criteria, and the high intraobserver and interobserver variabilities in the nonneoplastic (regenerative)–neoplastic spectrum.

Objective.—To provide an overview of the current concepts and unresolved issues surrounding the diagnosis of diseases in the nonneoplastic-neoplastic spectrum, and to discuss some noteworthy properties and histologic features of gastric epithelial lesions.

Data Sources.—A comprehensive assessment of the medical literature on gastric epithelial lesions was performed; we also interjected our own experiences into the discussion. Sources included original studies, review articles, and textbooks related to the field.

Conclusions.—Our literature review revealed that clear cell changes and micropapillary carcinoma components in gastric carcinomas are associated with poor clinical outcomes and should hence be included in pathologic reports. Moreover, we suggest a stepwise biopsy–endoscopic resection modality for the diagnosis of borderline neoplasia-nonneoplasia cases.
The Librarian Leading the Machine: A Reassessment of Library Instruction Methods
Authors: Greer Katie , Hess Amanda Nichols , Kraemer Elizabeth W.
Published: April 2016

This article builds on the 2007 College and Research Libraries article, “The Librarian, the Machine, or a Little of Bsoth.” Since that time, Oakland University Libraries implemented changes to its instruction program that reflect larger trends in teaching and assessment throughout the profession; following these revisions, librarians undertook a new study to assess the effectiveness of online library instruction in face-to-face courses in comparison to the hybrid model that had been in place. The study’s design and its results serve to contribute to discussion of best practices in information literacy pedagogy, online learning, instructional design, and the role of the librarian therein.
The “other” side of infidelity: The experience of the “other” partner, anxious love, and implications for practitioners
Authors: DePompo Paul , Butsuhara Misa
Published: April 2016

Research on affairs has failed to acknowledge the “other woman” or “other man,” focusing only on the married spouses. The goal of this study was to explore the unique experience of the “other” partner to determine aspects critical to the navigation and healing process of these relationships. In this qualitative study, 49 participants, between the ages of 23 and 60 (N = 49; 31f, 18m), who were engaged in meaningful relationships with married partners completed a set of questionnaires and engaged in a semi-structured interview. Measures, which included the Beck Depression Inventory-II (BDI-II), Beck Anxiety Inventory (BAI), and The Experience in Close Relationships Questionnaire Revised (ECR-R), indicated clinical levels of anxiety and maladaptive attachment styles among all participants. Seven themes emerged into a model that incorporates the role of anxiety, along with the origin and maintenance of these relationships. A protocol that combines areas of trauma, GAD, and social anxiety will likely be beneficial.
Inhibitory Effects of the Aerial Parts of Epimedium koreanum on TPA-Induced Inflammation and Promotion in Two-Stage Carcinogenesis in Mouse Skin
Authors: Ken Yasukawa  , Sung-Kwon Ko  , Wan-Kyunn Whang
Published: April 2016

Cancer prevention by supplements offers the most cost-effective long-term health strategy. Methanol extracts from the aerial parts of Epimediumkoreanum were previously found to inhibit 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammatory ear oedema and tumour promotion by TPA in the two-stage mouse skin carcinogenesis model. Four prenyl flavonol glycosides (14) were isolated from the active fraction of this extract, and were identified. The isolated compounds showed inhibitory activity against TPA-induced ear inflammatory ear oedema. The 50% inhibitory dose (ID50) of icariin (1), epimedin A (2), epimedin B (3) and epimedin C (4) for TPA-induced inflammation ranged from 114 to 255 nmol/ear, suggesting greater potency than indomethacin (ID50: 908 nmol/ear), an anti-inflammatory drug. Thus, the epimedium herb may be useful in cancer prevention.
Punctuated evolution and transitional hybrid network in an ancestral cell cycle of fungi
Authors: Medina Edgar M , Turner Jonathan J , Gordân Raluca , Skotheim Jan M , Buchler Nicolas E
Published: April 2016

Although cell cycle control is an ancient, conserved, and essential process, some core animal and fungal cell cycle regulators share no more sequence identity than non-homologous proteins. Here, we show that evolution along the fungal lineage was punctuated by the early acquisition and entrainment of the SBF transcription factor through horizontal gene transfer. Cell cycle evolution in the fungal ancestor then proceeded through a hybrid network containing both SBF and its ancestral animal counterpart E2F, which is still maintained in many basal fungi. We hypothesize that a virally-derived SBF may have initially hijacked cell cycle control by activating transcription via the cis-regulatory elements targeted by the ancestral cell cycle regulator E2F, much like extant viral oncogenes. Consistent with this hypothesis, we show that SBF can regulate promoters with E2F binding sites in budding yeast.
Nucleosome breathing and remodeling constrain CRISPR-Cas9 function
Authors: Isaac R Stefan , Jiang Fuguo , Doudna Jennifer A , Lim Wendell A , Narlikar Geeta J , Almeida Ricardo
Published: April 2016

The CRISPR-Cas9 bacterial surveillance system has become a versatile tool for genome editing and gene regulation in eukaryotic cells, yet how CRISPR-Cas9 contends with the barriers presented by eukaryotic chromatin is poorly understood. Here we investigate how the smallest unit of chromatin, a nucleosome, constrains the activity of the CRISPR-Cas9 system. We find that nucleosomes assembled on native DNA sequences are permissive to Cas9 action. However, the accessibility of nucleosomal DNA to Cas9 is variable over several orders of magnitude depending on dynamic properties of the DNA sequence and the distance of the PAM site from the nucleosome dyad. We further find that chromatin remodeling enzymes stimulate Cas9 activity on nucleosomal templates. Our findings imply that the spontaneous breathing of nucleosomal DNA together with the action of chromatin remodelers allow Cas9 to effectively act on chromatin in vivo.
The role of piriform associative connections in odor categorization
Authors: Bao Xiaojun , Raguet Louise LG , Cole Sydni M , Howard James D , Gottfried Jay A
Published: April 2016

Distributed neural activity patterns are widely proposed to underlie object identification and categorization in the brain. In the olfactory domain, pattern-based representations of odor objects are encoded in piriform cortex. This region receives both afferent and associative inputs, though their relative contributions to odor perception are poorly understood. Here, we combined a placebo-controlled pharmacological fMRI paradigm with multivariate pattern analyses to test the role of associative connections in sustaining olfactory categorical representations. Administration of baclofen, a GABA(B) agonist known to attenuate piriform associative inputs, interfered with within-category pattern separation in piriform cortex, and the magnitude of this drug-induced change predicted perceptual alterations in fine-odor discrimination performance. Comparatively, baclofen reduced pattern separation between odor categories in orbitofrontal cortex, and impeded within-category generalization in hippocampus. Our findings suggest that odor categorization is a dynamic process concurrently engaging stimulus discrimination and generalization at different stages of olfactory information processing, and highlight the importance of associative networks in maintaining categorical boundaries.
Mode switching in volcanic seismicity: El Hierro 2011–2013
Authors: Roberts Nick S. , Bell Andrew F. , Main Ian G.
Published: April 2016

The Gutenberg‐Richter b value is commonly used in volcanic eruption forecasting to infer material or mechanical properties from earthquake distributions. Such studies typically analyze discrete time windows or phases, but the choice of such windows is subjective and can introduce significant bias. Here we minimize this sample bias by iteratively sampling catalogs with randomly chosen windows and then stack the resulting probability density functions for the estimated
value to determine a net probability density function. We examine data from the El Hierro seismic catalog during a period of unrest in 2011–2013 and demonstrate clear multimodal behavior. Individual modes are relatively stable in time, but the most probable
value intermittently switches between modes, one of which is similar to that of tectonic seismicity. Multimodality is primarily associated with intermittent activation and cessation of activity in different parts of the volcanic system rather than with respect to any systematic inferred underlying process.
Direct measurement of electron sloshing of an inertial Alfvén wave
Authors: Schroeder J. W. R. , Skiff F. , Kletzing C. A. , Howes G. G. , Carter T. A. , Dorfman S.
Published: April 2016

We report laboratory measurements of the parallel current carried by suprathermal electrons associated with inertial Alfvén wave excitation in the laboratory. The experiments presented here use a novel wave absorption diagnostic that measures the suprathermal tails of the electron distribution parallel to the mean magnetic field. The diagnostic is used to probe the electron distribution as an inertial Alfvén wave propagates along the mean magnetic field. These results identify, for the first time, the periodic motion of suprathermal electrons participating in the inertial Alfvén wave itself, in agreement with predictions from linear kinetic theory.
A Microfluidic Paper‐Based Origami Nanobiosensor for Label‐Free, Ultrasensitive Immunoassays
Authors: Li Xiao , Liu Xinyu
Published: April 2016

Microfluidic paper‐based analytical devices (μPADs) represent a promising platform technology for point‐of‐care diagnosis. Highly sensitive, rapid, and easy‐to‐perform immunoassays implemented on μPADs are desirable to fulfill the promise of the μPAD technology. This article reports the first microfluidic paper‐based origami nanobiosensor (origami μPAD), which integrates zinc oxide nanowires (ZnO NWs) and electrochemical impedance spectroscopy (EIS) biosensing mechanism, for label‐free, ultrasensitive immunoassays. The EIS mechanism features simple and label‐free assay operations which take less than 25 min to be finished, while the ZnO NWs allow covalent bonding for immobilizing probe proteins and improve the biosensing performance with such features as high surface‐area‐to‐volume ratios and high sensitivity to surface binding. The calibration of the device reveals an ultralow limit of detection (LOD) of 60 fg mL−1 (>100 times lower than those of existing μPADs) for rabbit immunoglobulin G in phosphate‐buffered saline. The detection of human immunodeficiency virus p24 antigen in human serum with a low LOD of 300 fg mL−1 (>33 times lower than that of a commercial p24 antigen test kit) is also demonstrated. This novel μPAD design offers ultrahigh sensitivity, short assay time, and ease of operation, and thus possesses significant potential for low‐cost, rapid molecular diagnosis of early‐stage diseases.
The association between low blood lead levels and the prevalence of prehypertension among nonhypertensive adults in Korea
Authors: Lee Wanhyung , Yoon Jin‐ha , Roh Jaehoon , Lee Seunghyun , Seok Hongdeok , Lee June‐hee , Jung Pil Kyun , Rhie Jeongbae , Won Jong‐uk
Published: April 2016

Objectives

Low‐level lead exposure has been associated with increases in blood pressure (BP) and impairment of the cardiovascular system. Prehypertension is not categorized as a disease currently; however, individuals with untreated prehypertension are known to be at increased risk of progression to hypertension and mortality caused by cardiovascular disease. We investigated the association between blood lead levels below the threshold for the harmful effects of lead and the prevalence of prehypertension in Korean adults.

Methods

A total of 8,493 participants (3,945 men and 4,548 women) were included in the current analysis, using data from the fourth, fifth, and sixth Korean National Health and Nutrition Examination Survey (KNHANES) in 2007–2013. Blood analysis, self‐report questionnaires, and physical examinations were used to assess blood lead levels, BP, and medical history. Odds ratios (OR) and 95% confidence intervals (95% CI) for prehypertension were calculated using multiple logistic regression models.

Results

Compared to the first quartile (Q1) blood lead level (0.206–1.539 μg/dl), the ORs (95% CI) were 1.24 (1.04–1.48) in Q2, (1.540–2.056 μg/dl), 1.27 (1.06–1.52) in Q3, (2.057–2.716 μg/dl), and 1.30 (1.07–1.60) in Q4 (2.717–24.532 μg/dl) for the prevalence of prehypertension after adjusting for age, sex, morbidity status, socioeconomic status, and health behavioral variables.

Conclusions

Our large, cross‐sectional, nationwide study revealed that blood lead levels below the threshold for the harmful effects of lead were significantly associated with prehypertension. Am. J. Hum. Biol. 28:729–735, 2016. © 2016 Wiley Periodicals, Inc.
Automated quantification of abdominal adiposity by magnetic resonance imaging
Authors: Sun Jingjing , Xu Bugao , Freeland‐Graves Jeanne
Published: April 2016

Objectives

To develop a fully‐automated algorithm to process axial magnetic resonance imaging (MRI) slices for quantifying abdominal visceral, subcutaneous and total adipose tissues, i.e., VAT, SAT, and TAT, without human intervention or prior knowledge.

Materials and Methods

Fat regions in single MRI slice or sequence (20 slices) were identified with image processing techniques including region‐growing, inhomogeneity correction, fuzzy c‐means clustering, and active contours segmentation. The MR images of 85 subjects (60 males and 25 females), whose body mass index (BMI) values ranged from 19.96 to 40.35 kg/m2, were analyzed using the fully‐automated algorithm—the automatic method developed in the research and the widely used semi‐automated software (sliceOmatic® Tomovision, Inc.)—the reference method.

Results

The proposed automated method showed good performance against the reference method to quantify adipose tissues in both single umbilical slice and MRI sequence. The square of the Pearson correlation coefficients (R2) based on the results generated from the two methods for VAT/SAT/TAT were 0.977/0.998/0.997 for single slice data and 0.995/0.999/0.999 for volumetric data. The intra‐class correlation of visceral adipose tissue (VAT) between the three operators was 0.939 in the reference method, which was improved to 0.999 in the automatic method. The adipose tissue measurements in the slice at Lumbar 3 vertebra have the highest correlation with the total fat volumes across the entire abdomen.

Conclusion

The fully‐automated algorithm presented in the paper provides an accurate and reliable assessment of abdominal fat without human intervention. Am. J. Hum. Biol. 28:757–766, 2016. © 2016Wiley Periodicals, Inc.
Rational Design of Amine Nucleophiles for Dynamic Kinetic Resolution of Azlactones Leading to Highly Enantioselective Synthesis of Bisamides
Authors: Zhang Yu‐Chen , Yang Qin , Yang Xue , Zhu Qiu‐Ning , Shi Feng
Published: April 2016

The first catalytic asymmetric aminolysis of azlactones was achieved, enabling the highly enantioselective dynamic kinetic resolution of azlactones. This was demonstrated to be an efficient method for synthesizing optically pure bisamides in high yield with excellent enantioselectivity (up to 99 % yield, 99 % ee). The rational design of the amine nucleophile bearing both a sterically bulky group and an activating group was shown to be a key factor in attaining excellent enantioselectivity in the catalytic asymmetric aminolysis of azlactones. This approach not only provides easy access to biologically important enantiopure bisamides, but also enables the dynamic kinetic resolution of azlactones by using a strategy of enantioselective aminolysis, which was previously unknown in this research field.
Polyimide fibers prepared by a dry‐spinning process: Enhanced mechanical properties of fibers containing biphenyl units
Authors: Wang Shihua , Dong Jie , Li Zhentao , Xu Yuan , Tan Wenjun , Zhao Xin , Zhang Qinghua
Published: April 2016

Polyimide (PI) fibers with enhanced mechanical properties and high thermal and dimensional stability were prepared via a two‐step dry‐spinning process through the introduction of 3,3′,4,4′‐biphenyl tetracarboxylic dianhydride (BPDA) containing biphenyl units into rigid homopolyimide of pyromellitic dianhydride (PMDA) and 4,4′‐oxydianiline. The attenuated total reflectance–Fourier transform infrared spectra results imply that the incorporated BPDA moieties accelerate the imidization process and increase the imidization degree (ID) of the precursor fibers; this was attributed to the increased molecular mobility of the polymer chains. Two‐dimensional wide‐angle X‐ray diffraction spectra indicated that the prepared PI fibers possessed a well‐defined crystal structure and polymer chains in the crystalline region were highly oriented along the fiber axis. The PI fiber, with the molar ratio of PMDA/BPDA being 7/3, showed optimum tensile strength and modulus values of 8.55 and 73.21 cN/dtex, respectively; these were attributed to the high IDs and molecular weights. Meanwhile, the PI fibers showed better dimensional stability than the commercial P84 fiber, and this is beneficial for its security applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43727.
Encapsulation of hydrophobic or hydrophilic iron oxide nanoparticles into poly(lactic acid) micro/nanoparticles via adaptable emulsion setup
Authors: Song Anna , Ji Shaowen , Sook Hong Joung , Ji Yi , Gokhale Ankush A. , Lee Ilsoon
Published: April 2016

In this study, a one‐step water‐in‐oil‐in‐water (W/O/W) emulsion process was employed to encapsulate either hydrophilic (∼10 nm) or hydrophobic (∼5 nm) iron oxide nanoparticles (IONPs) into poly(lactic acid) (PLA). Via the simple adjustment of emulsification temperature to high temperature (HT, 60 °C) or room temperature (RT, 25 °C), a transformation of PLA‐IONPs composite particles from hollow microparticles to solid nanospheres can be achieved. At RT, PLA nanocomposite particles (30–200 nm) encapsulating IONPs were generated regardless of the hydrophobicity of IONPs. On the other hand, at HT, our method resulted in the hollow microparticles (2–5 µm). This study presents a fast and easily adaptable process to encapsulate either hydrophobic or hydrophilic IONPs into the hydrophobic polymeric particles, with different shapes and sizes, by simply adjusting the emulsification temperature through the one‐step W/O/W emulsion. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43749.
Green Tea and Glycine Modulate the Activity of Metalloproteinases and Collagen in the Tendinitis of the Myotendinous Junction of the Achilles Tendon
Authors: Vieira Cristiano Pedrozo , De Oliveira LetÍCia Prado , Da Ré Guerra Flávia , Marcondes Maria Cristina Cintra , Pimentel Edson Rosa
Published: April 2016

The myotendinous junction (MTJ) is the weakest element in the muscle‐tendon unit of the heel, and thus the most susceptible to injuries. The scarcity of adequate treatments means that tendinitis is a major concern to athletes and other groups who depend on their physical fitness, although green tea and glycine have both been shown to have beneficial effects on the inflammation. The present study investigated the remodeling effects of green tea and glycine in the MTJ of rats with tendinitis. For this, male Wistar rats were divided into five groups: animals without tendinitis and animals with tendinitis; animals with tendinitis supplied with green tea; animals with tendinitis supplied with a glycine diet; animals with tendinitis supplied with a green tea and glycine diet. Tendinitis was induced and the treatment with green tea (700 mg/kg/day) and a 5% glycine diet lasted 7 days. The treatments regulated the activity of metalloproteinases (MMP)‐2, ‐8, and ‐9, and induced the synthesis of type I collagen, glycosaminoglycans, and non‐collagenous proteins. Changes were also noted in the compaction of the collagen molecules and the amount of tenocytes. When combined, green tea and glycine modulated the inflammatory process and induced the synthesis of the elements involved in the post‐lesion recovery of the tissue. The data from the MTJ were different when compared with results already published using the whole Achilles tendon. These data indicate that each region of the inflamed tendon can exhibit different responses during the treatment and therefore, modify its extracellular matrix components to facilitate recovery and repair. Anat Rec, 299:918–928, 2016. © 2016 Wiley Periodicals, Inc.
On‐body calibration and measurements using personal radiofrequency exposimeters in indoor diffuse and specular environments
Authors: Aminzadeh Reza , Thielens Arno , Bamba Aliou , Kone Lamine , Gaillot Davy Paul , Lienard Martine , Martens Luc , Joseph Wout
Published: April 2016

For the first time, response of personal exposimeters (PEMs) is studied under diffuse field exposure in indoor environments. To this aim, both numerical simulations, using finite‐difference time‐domain method, and calibration measurements were performed in the range of 880–5875 MHz covering 10 frequency bands in Belgium. Two PEMs were mounted on the body of a human male subject and calibrated on‐body in an anechoic chamber (non‐diffuse) and a reverberation chamber (RC) (diffuse fields). This was motivated by the fact that electromagnetic waves in indoor environments have both specular and diffuse components. Both calibrations show that PEMs underestimate actual incident electromagnetic fields. This can be compensated by using an on‐body response. Moreover, it is shown that these responses are different in anechoic chamber and RC. Therefore, it is advised to use an on‐body calibration in an RC in future indoor PEM measurements where diffuse fields are present. Using the response averaged over two PEMs reduced measurement uncertainty compared to single PEMs. Following the calibration, measurements in a realistic indoor environment were done for wireless fidelity (WiFi‐5G) band. Measured power density values are maximally 8.9 mW/m2 and 165.8 μW/m2 on average. These satisfy reference levels issued by the International Commission on Non‐Ionizing Radiation Protection in 1998. Power density values obtained by applying on‐body calibration in RC are higher than values obtained from no body calibration (only PEMs) and on‐body calibration in anechoic room, by factors of 7.55 and 2.21, respectively. Bioelectromagnetics. 37:298–309, 2016. © 2016 Wiley Periodicals, Inc.
Risk factors for recurrence in patients with papillary thyroid carcinoma undergoing modified radical neck dissection
Authors: Lee Y M , Sung T Y , Kim W B , Chung K W , Yoon J H , Hong S J
Published: April 2016

Background

This study evaluated the impact of lymph node-related factors on the risk of and site of recurrence in patients who had papillary thyroid carcinoma with lymph node metastasis in the lateral compartment (classified as pN1b).

Methods

Patients underwent total thyroidectomy with unilateral modified radical neck dissection for classical papillary thyroid carcinoma. Risk factors for recurrence were evaluated according to the pattern of recurrence.

Results

A total of 324 patients were included in the study. The median follow-up was 63 (range 14–181) months. Recurrence was detected in 47 patients (14·5 per cent). In the multivariable analysis, a maximum diameter of metastatic lymph nodes larger than 2·0 cm (hazard ratio (HR) 1·15, 95 per cent c.i. 1·06 to 1·25; P = 0·033) and a central compartment metastatic lymph node ratio of more than 0·42 (HR 3·35, 1·65 to 6·79; P < 0·001) were identified as independent risk factors for locoregional recurrence. Age 45 years or older (HR 5·69, 1·24 to 26·12; P = 0·025) and extranodal extension of metastasis (HR 12·71, 1·64 to 98·25; P = 0·015) were risk factors for distant metastasis. In subgroup analysis of locoregional recurrence, several lymph node-related factors affected the risk of recurrence according to the specific site of metastasis.

Conclusion

Lymph node-related factors are of importance for the risk of recurrence in patients with classical papillary thyroid carcinoma classified as pN1b.
Development of a structured undergraduate research experience: Framework and implications
Authors: Brown Anne M. , Lewis Stephanie N. , Bevan David R.
Published: April 2016

Participating in undergraduate research can be a pivotal experience for students in life science disciplines. Development of critical thinking skills, in addition to conveying scientific ideas in oral and written formats, is essential to ensuring that students develop a greater understanding of basic scientific knowledge and the research process. Modernizing the current life sciences research environment to accommodate the growing demand by students for experiential learning is needed. By developing and implementing a structured, theory‐based approach to undergraduate research in the life sciences, specifically biochemistry, it has been successfully shown that more students can be provided with a high‐quality, high‐impact research experience. The structure of this approach allowed students to develop novel, independent projects in a computational molecular modeling lab. Students engaged in an experience in which career goals, problem‐solving skills, time management skills, and independence in a research lab were developed. After experiencing this approach to undergraduate research, students reported feeling challenged to think critically and prepared for future career paths. The approach allowed for a progressive learning environment where more undergraduate students could participate in publishable research. Future areas for development include implementation in a bench‐top lab and extension to disciplines beyond biochemistry. In this study, it has been shown that utilizing the structured approach to undergraduate research could allow for more students to experience undergraduate research and develop into more confident, independent life scientists well prepared for graduate schools and professional research environments. © 2016 by The International Union of Biochemistry and Molecular Biology, 44(5):463–474, 2016.
Reversible Gel–Sol Transition of a Photo‐Responsive DNA Gel
Authors: Kandatsu Daisuke , Cervantes‐Salguero Keitel , Kawamata Ibuki , Hamada Shogo , Nomura Shin‐ichiro M. , Fujimoto Kenzo , Murata Satoshi
Published: April 2016

Stimuli‐responsive DNA gels that can undergo a sol‐gel transition in response to photo‐irradiation provide a way to engineer functional gel material with fully designed DNA base sequences. We propose an X‐shaped DNA motif that turns into a gel by hybridization of self‐complementary sticky ends. By embedding a photo‐crosslinking artificial base in the sticky‐end sequence, repetitive gel–sol transitions are achieved through UV irradiation at different wavelengths. The concentration of the DNA motif necessary for gelation is as low as 40 μm after modification of the geometrical properties of the motif. The physical properties, such as swelling degree and diffusion coefficient, were assessed experimentally.
Screening, Molecular Cloning, and Biochemical Characterization of an Alcohol Dehydrogenase from Pichia pastoris Useful for the Kinetic Resolution of a Racemic β‐Hydroxy‐β‐trifluoromethyl Ketone
Authors: Bulut Dalia , Duangdee Nongnaphat , Gröger Harald , Berkessel Albrecht , Hummel Werner
Published: April 2016

The stereoselective synthesis of chiral 1,3‐diols with the aid of biocatalysts is an attractive tool in organic chemistry. Besides the reduction of diketones, an alternative approach consists of the stereoselective reduction of β‐hydroxy ketones (aldols). Thus, we screened for an alcohol dehydrogenase (ADH) that would selectively reduce a β‐hydroxy‐β‐trifluoromethyl ketone. One potential starting material for this process is readily available by aldol addition of acetone to 2,2,2‐trifluoroacetophenone. Over 200 strains were screened, and only a few yeast strains showed stereoselective reduction activities. The enzyme responsible for the reduction of the β‐hydroxy‐β‐trifluoromethyl ketone was identified after purification and subsequent MALDI‐TOF mass spectrometric analysis. As a result, a new NADP+‐dependent ADH from Pichia pastoris (PPADH) was identified and confirmed to be capable of stereospecific and diastereoselective reduction of the β‐hydroxy‐β‐trifluoromethyl ketone to its corresponding 1,3‐diol. The gene encoding PPADH was cloned and heterologously expressed in Escherichia coli BL21(DE3). To determine the influence of an N‐ or C‐terminal His‐tag fusion, three different recombinant plasmids were constructed. Interestingly, the variant with the N‐terminal His‐tag showed the highest activity; consequently, this variant was purified and characterized. Kinetic parameters and the dependency of activity on pH and temperature were determined. PPADH shows a substrate preference for the reduction of linear and branched aliphatic aldehydes. Surprisingly, the enzyme shows no comparable activity towards ketones other than the β‐hydroxy‐β‐trifluoromethyl ketone.
Reduction‐Responsive Guanine Incorporated into G‐Quadruplex‐Forming DNA
Authors: Ikeda Masato , Kamimura Masahiro , Hayakawa Yukiko , Shibata Aya , Kitade Yukio
Published: April 2016

Stimulus‐responsive biomolecules are attractive targets to understand biomolecule behaviour as well as to explore their therapeutic and diagnostic applications. We demonstrate that a reduction‐responsive cleavable group (chemically caged unit) introduced into the guanine ring enables modulation of the secondary structure transition of an oligonucleotide in a reduction‐responsive and traceless manner leaving the unmodified oligonucleotide of interest. This simple but robust strategy could yield a variety of stimuli‐responsive oligonucleotides.
A Disassembly Strategy for Imaging Endogenous Pyrophosphate in Mitochondria by Using an FeIII–salen Complex
Authors: Kumari Namita , Huang Huaiyi , Chao Hui , Gasser Gilles , Zelder Felix
Published: April 2016

Inorganic pyrophosphate (PPi) is produced from nucleoside triphosphates in important biosynthetic reactions and is considered a diagnostic marker for various diseases, such as cancer, crystal deposition disease, and arthritis. Traditional methods for biological PPi detection rely on off‐line analytics after sample destruction. Molecular probes for imaging this biologically important analyte with temporal and spatial control in living cells are currently in demand. Herein, we report an FeIII–salen complex as the first small reaction‐based probe for endogenous mitochondrial PPi following a disassembly approach. Significantly, we successfully applied this complex for the detection of increased cellular PPi levels, and its performance was not affected by the presence of mitochondrial ATP in living cells.
Substrate‐Determined Diastereoselectivity in an Enzymatic Carboligation
Authors: Lehwald Patrizia , Fuchs Olga , Nafie Laurence A. , Müller Michael , Lüdeke Steffen
Published: April 2016

Thiamine diphosphate‐dependent enzymes catalyze the formation of C−C bonds, thereby generating chiral secondary or tertiary alcohols. By the use of vibrational circular dichroism (VCD) spectroscopy we studied the stereoselectivity of carboligations catalyzed by YerE, a carbohydrate‐modifying enzyme from Yersinia pseudotuberculosis. Conversion of the non‐physiological substrate (R)‐3‐methylcyclohexanone led to an R,R‐configured tertiary alcohol (diastereomeric ratio (dr) >99:1), whereas the corresponding reaction with the S enantiomer gave the S,S‐configured product (dr>99:1). This suggests that YerE‐catalyzed carboligations can undergo either an R‐ or an S‐specific pathway. We show that, in this case, the high stereoselectivity of the YerE‐catalyzed reaction depends on the substrate's preference to acquire a low‐energy conformation.
Enabling Better Electrochemical Activity Studies of H2O‐Soluble Au Clusters by Phase Transfer and a Case Study of Lipoic‐Acid‐Stabilized Au22
Authors: Padelford Jonathan W. , Wang Tanyu , Wang Gangli
Published: April 2016

In stark contrast to organic systems, insight of the electrochemical properties is rather limited in aqueous solution for Au clusters, which have received extensive research attention recently. We demonstrate phase transfer as an efficient strategy to shuttle the Au nanoclusters between aqueous and organic solvents cyclically. The ability to phase transfer the Au clusters circumvents the limitations of potential window and high dielectric constant of water for electrochemistry studies. Two types of ligand molecular structures were employed with different hydrophilicity/hydrophobicity: mercaptosuccinic acid and lipoic acid, the latter featuring a longer hydrophobic portion and disulfide group (for Au bonding). The transfer efficiency was evaluated at different pHs. Additional redox activities from the Au22LA12 cluster that could not be seen from aqueous measurements were successfully resolved. Reversible and controllable transfer between aqueous and organic phases is believed to be a generalizable approach that could enable broader applications.
Effective Inhibition of Cellular ROS Production by MXCXXC‐Type Peptides: Potential Therapeutic Applications in Copper‐Homeostasis Disorders
Authors: Shoshan Michal S. , Tshuva Edit Y.
Published: April 2016

Cyclic and acyclic peptides with sequences derived from metallochaperone binding sites, but differing at position 2, were analyzed for their inhibitory reactivity towards cellular ROS (reactive oxygen species) formation and catalytic activity towards oxidation with H2O2, in comparison with three commercial drugs clinically employed in chelation therapy for Wilson's disease. Acyclic peptides were more effective inhibitors than the cyclic ones, with one leading peptide with threonine at position 2 systematically showing the highest efficiency in reducing cellular ROS levels and in inhibiting Cu oxidation. This peptide was more effective than all commercial drugs in all aspects analyzed, and showed no toxicity towards human colon HT‐29 cancer cells at concentrations 10–100 times higher than the IC50 of the commercial drugs, corroborating its high medicinal potential.
Zn or O? An Atomic Level Comparison on Antibacterial Activities of Zinc Oxides
Authors: Yu Fen , Fang Xuan , Jia Huimin , Liu Miaoxing , Shi Xiaotong , Xue Chaowen , Chen Tingtao , Wei Zhipeng , Fang Fang , Zhu Hui , Xin Hongbo , Feng Jing , Wang Xiaolei
Published: April 2016

For the first time, the influence of different types of atoms (Zn and O) on the antibacterial activities of nanosized ZnO was quantitatively evaluated with the aid of a 3D‐printing‐manufactured evaluation system. Two different outermost atomic layers were manufactured separately by using an ALD (atomic layer deposition) method. Interestingly, we found that each outermost atomic layer exhibited certain differences against gram‐positive or gram‐negative bacterial species. Zinc atoms as outermost layer (ZnO−Zn) showed a more pronounced antibacterial effect towards gram‐negative E. coli (Escherichia coli), whereas oxygen atoms (ZnO−O) showed a stronger antibacterial activity against gram‐positive S. aureus (Staphylococcus aureus). A possible antibacterial mechanism has been comprehensively discussed from different perspectives, including Zn2+ concentrations, oxygen vacancies, photocatalytic activities and the DNA structural characteristics of different bacterial species.
Suppression of Photocyclization: Stabilization of an Aggregation‐Induced Tetraaryldistyrylbenzene Emitter
Authors: Freudenberg Jan , Rominger Frank , Bunz Uwe H. F.
Published: April 2016

The synthesis of 2,3,5,6‐tetrakis(2,6‐difluorophenyl)di(styryl)benzene by using a conventional synthetic sequence, including Diels–Alder and Horner reactions is reported. The target is an effective aggregation‐induced emitter. It is photostable with respect to electrocyclization, due to the presence of the fluorine substituents. This compound undergoes photochemical trans/cis isomerization of its styryl double bonds.
A Rapid and Sensitive Strip‐Based Quick Test for Nerve Agents Tabun, Sarin, and Soman Using BODIPY‐Modified Silica Materials
Authors: Climent Estela , Biyikal Mustafa , Gawlitza Kornelia , Dropa Tomáš , Urban Martin , Costero Ana M. , Martínez‐Máñez Ramón , Rurack Knut
Published: April 2016

Test strips that in combination with a portable fluorescence reader or digital camera can rapidly and selectively detect chemical warfare agents (CWAs) such as Tabun (GA), Sarin (GB), and Soman (GD) and their simulants in the gas phase have been developed. The strips contain spots of a hybrid indicator material consisting of a fluorescent BODIPY indicator covalently anchored into the channels of mesoporous SBA silica microparticles. The fluorescence quenching response allows the sensitive detection of CWAs in the μg m−3 range in a few seconds.
Sophisticated Design of Covalent Organic Frameworks with Controllable Bimetallic Docking for a Cascade Reaction
Authors: Leng Wenguang , Peng Yongsheng , Zhang Jianqiang , Lu Hui , Feng Xiao , Ge Rile , Dong Bin , Wang Bo , Hu Xiangping , Gao Yanan
Published: April 2016

Precise control of the number and position of the catalytic metal ions in heterogeneous catalysts remains a big challenge. Here we synthesized a series of two‐dimensional (2D) covalent organic frameworks (COFs) containing two different types of nitrogen ligands, namely imine and bipyridine, with controllable contents. For the first time, the selective coordination of the two nitrogen ligands of the 2D COFs to two different metal complexes, chloro(1,5‐cyclooctadiene)rhodium(I) (Rh(COD)Cl) and palladium(II) acetate (Pd(OAc)2), has been realized using a programmed synthetic procedure. The bimetallically docked COFs showed excellent catalytic activity in a one‐pot addition–oxidation cascade reaction. The high surface area, controllable metal‐loading content, and predesigned active sites make them ideal candidates for their use as heterogeneous catalysts in a wide range of chemical reactions.
Triflic Acid‐Catalyzed Enynes Cyclization: A New Strategy beyond Electrophilic π‐Activation
Authors: Yu Zhunzhun , Liu Lu , Zhang Junliang
Published: April 2016

The cyclization of enynes, catalyzed by a transition metal, represents a powerful tool to construct an array of cyclic compounds through electrophilic π‐activation. In this paper, we disclose a new and efficient strategy for enynes cyclization catalyzed by triflic acid. The salient features of this transformation includes a broad substrate scope, metal free synthesis, open flask and mild conditions, good yields, ease of operation, low catalyst loading, and easy scale‐up to gram scale. A preliminary mechanism study demonstrated that the activation model of the reaction was σ‐activation, which is different from the transition‐metal‐catalyzed enynes cyclization. Our strategy affords a complementary method to the traditional strategies, which use transition‐metal catalysts.
A Capped Octahedral MHC6 Compound of a Platinum Group Metal
Authors: Eguillor Beatriz , Esteruelas Miguel A. , Lezáun Virginia , Oliván Montserrat , Oñate Enrique , Tsai Jui‐Yi , Xia Chuanjun
Published: April 2016

A MHC6 complex of a platinum group metal with a capped octahedral arrangement of donor atoms around the metal center has been characterized. This osmium compound OsH{κ2‐C,C‐(PhBIm‐C6H4)}3, which reacts with HBF4 to afford the 14 e− species [Os{κ2‐C,C‐(PhBIm‐C6H4)}(Ph2BIm)2]BF4 stabilized by two agostic interactions, has been obtained by reaction of OsH6(PiPr3)2 with N,N′‐diphenylbenzimidazolium chloride ([Ph2BImH]Cl) in the presence of NEt3. Its formation takes place through the C,C,C‐pincer compound OsH2{κ3‐C,C,C‐(C6H4‐BIm‐C6H4)}(PiPr3)2, the dihydrogen derivative OsCl{κ2‐C,C‐(PhBIm‐C6H4)}(η2‐H2)(PiPr3)2, and the five‐coordinate osmium(II) species OsCl{κ2‐C,C‐(PhBIm‐C6H4)}(PiPr3)2.
Weak O‐Assistance Outcompeting Strong N,N‐Bidentate Directing Groups in Copper‐Catalyzed C−H Chalcogenation
Authors: Cera Gianpiero , Ackermann Lutz
Published: April 2016

A copper‐mediated C−H chalcogenation of triazoles has been achieved by weak coordination. The user‐friendly protocol showed high functional‐group tolerance and ample substrate scope, yielding fully substituted 1,2,3‐triazoles with complete positional site‐selectivity. The C−H selenylation could likewise be achieved by means of copper catalysis. Our findings highlight for the first time that weak O‐coordination can outcompete the strong N,N‐bidentate coordination mode in C−H functionalization technology.
Catalyst‐Driven Scaffold Diversity: Selective Synthesis of Spirocycles, Carbazoles and Quinolines from Indolyl Ynones
Authors: Liddon John T. R. , James Michael J. , Clarke Aimee K. , O'Brien Peter , Taylor Richard J. K. , Unsworth William P.
Published: April 2016

Medicinally relevant spirocyclic indolenines, carbazoles and quinolines can each be directly synthesised selectively from common indolyl ynone starting materials by catalyst variation. The high yielding, divergent reactions all proceed by an initial dearomatising spirocyclisation reaction to generate an intermediate vinyl–metal species, which then rearranges selectively by careful choice of catalyst and reaction conditions.
Multicomponent Double Diels–Alder/Nazarov Tandem Cyclization of Symmetric Cross‐Conjugated Diynones to Generate [6‐5‐6] Tricyclic Products
Authors: Carmichael Rachael A. , Chalifoux Wesley A.
Published: April 2016

The construction of complex polycyclic terpenoid products in an efficient and step‐economical manner using multicomponent and tandem processes is highly valuable. Herein, we report a tandem cyclization sequence that initiates with a multicomponent double Diels–Alder reaction of cross‐conjugated diynones, followed by a Nazarov cyclization to efficiently produce [6‐5‐6] tricyclic products with excellent regio‐ and diastereoselectivity. This methodology generates five new carbon–carbon bonds, three rings, quaternary or vicinal quaternary carbons, and stereogenic centers in a one‐pot reaction.
ChemInform Abstract: A THEORETICAL ANALYSIS OF THE OXIDATION OF IRON‐SILICON ALLOYS
Authors: ATKINSON A.
Published: April 2016

Die Analyse der Oxidation von Fe‐Si‐Legierungen in CO2 + 1 Vol‐% CO bei 500°C mit Hilfe einer phänomenologischen Theorie der Legierungsoxidation gestattet eine detaillierte Voraussage zur Mikrostruktur der gebildeten Oxidzunder.
ChemInform Abstract: RECOVERY OF HEAVY METALS WITH CALCIUM SILICON ALLOY. II. RECOVERY OF COPPER(II) IONS
Authors: TOKUNAGA S.
Published: April 2016

(′UHU‐Lösungen werden durch eine CTa‐Si‐Legierung (keine näheren Angaben) zum Metall reduziert.
ChemInform Abstract: CYCLOADDITION OF N‐PHENYLTRIAZOLINEDIONE AND 1,5‐DIALKYL SUBSTITUTED SEMIBULLVALENE
Authors: ASKANI R. , KIRSTEN R. , DUGALL B.
Published: April 2016

Das Bicyclooctadion (I) wird u.a. mit MeMgI bzw. LiAlH4 zu den Diolen (IIIa) bzw. (IIIb) umgesetzt, wobei bei der Darstellung von (IIIa) dieses zuerst isoliert und der Rest des Reaktionsgemisches mit I2 thermisch zu dem Bicyclooctenon (II) sowie den Bicyclodienen (IVa) und (Va) dehydratisiert wird.
ChemInform Abstract: REACTIONS OF KETONES WITH HYDROXYLAMINE‐O‐SULFONIC ACID
Authors: NOVOSELOV E. F. , ISAEV S. D. , YURCHENKO A. G. , VODICHKA L. , TRSHISKA YA.
Published: April 2016

Die alicyclischen Ketone bzw. Acetophenon (I) reagieren mit I‐Iydroxylamin‐O‐schwefelsäure zu den instabilen Sulfoketoximen, die mit NH3 in Form ihrer stabilen Ammoniumsalze (II) isoliert werden.