bluuebunny/crossref_metadata_2025 huggingface dataset:
Lack of evolution in a leaf beetle that lives on two contrasting host plants
Authors: Gould Katherine , Wilson Paul
Published: August 2015

The interactions between plant‐eating insects and their hosts have shaped both the insects and the plants, driving evolution of plant defenses and insect specialization. The leaf beetle Trirhabda eriodictyonis (Chrysomelidae) lives on two shrubs with differing defenses: Eriodictyon crassifolium has hairy leaves, whereas E. trichocalyx has resinous leaves. We tested whether these beetles have differentiated onto the two host plants, and if not, whether the beetles prefer the better host plant and prefer mates who are from that host plant. In feeding tests, adult beetles strongly preferred eating E. trichocalyx regardless of which host they came from. In addition, females laid more eggs if they ate E. trichocalyx than E. crassifolium. So, E. trichocalyx is generally the better host. However, beetle mate preference was not in line with food choice. Males did not prefer to mate with females from E. trichocalyx. Females from E. crassifolium did prefer males from E. trichocalyx over males from E. crassifolium, but did not lay more eggs as a result of these matings. We conclude that the beetle populations we studied have not differentiated based on their host plants and may not have even adapted to the better host. Although to humans these host plant defenses differ dramatically, signs that they have caused evolution in the beetles are lacking. The case of T. eriodictyonis stands counter to many other studies that have seen the differentiation of ecotypes and/or adaptive coordination of an herbivore's life cycle based on host plant differences.
Trade‐offs in the evolution of bumblebee colony and body size: a comparative analysis
Authors: Cueva del Castillo Raúl , Sanabria‐Urbán Salomón , Serrano‐Meneses Martín Alejandro
Published: August 2015

Trade‐offs between life‐history traits – such as fecundity and survival – have been demonstrated in several studies. In eusocial insects, the number of organisms and their body sizes can affect the fitness of the colony. Large‐than‐average body sizes as well as more individuals can improve a colony's thermoregulation, foraging efficiency, and fecundity. However, in bumblebees, large colonies and large body sizes depend largely on high temperatures and a large amount of food resources. Bumblebee taxa can be found in temperate and tropical regions of the world and differ markedly in their colony sizes and body sizes. Variation in colony size and body size may be explained by the costs and benefits associated with the evolutionary history of each species in a particular environment. In this study, we explored the effect of temperature and precipitation (the latter was used as an indirect indicator of food availability) on the colony and body size of twenty‐one bumblebee taxa. A comparative analysis controlling for phylogenetic effects as well as for the body size of queens, workers, and males in bumblebee taxa from temperate and tropical regions indicated that both temperature and precipitation affect colony and body size. We found a negative association between colony size and the rainiest trimester, and a positive association between the colony size and the warmest month of the year. In addition, male bumblebees tend to evolve larger body sizes in places where the rain occurs mostly in the summer and the overall temperature is warmer. Moreover, we found a negative relationship between colony size and body sizes of queens, workers, and males, suggesting potential trade‐offs in the evolution of bumblebee colony and body size.
Interspecific variation in the phenology of advertisement calling in a temperate Australian frog community
Authors: Heard Geoffrey W. , Canessa Stefano , Parris Kirsten M.
Published: August 2015

Spatial and temporal partitioning of resources underlies the coexistence of species with similar niches. In communities of frogs and toads, the phenology of advertisement calling provides insights into temporal partitioning of reproductive effort and its implications for community dynamics. This study assessed the phenology of advertisement calling in an anuran community from Melbourne, in southern Australia. We collated data from 1432 surveys of 253 sites and used logistic regression to quantify seasonality in the nightly probability of calling and the influence of meteorological variables on this probability for six species of frogs. We found limited overlap in the predicted seasonal peaks of calling among these species. Those shown to have overlapping calling peaks are unlikely to be in direct competition, due to differences in larval ecology (Crinia signifera and Litoria ewingii) or differences in calling behavior and acoustics (Limnodynastes dumerilii and Litoria raniformis). In contrast, closely related and ecologically similar species (Crinia signfera and Crinia parinsignifera; Litoria ewingii and Litoria verreauxii) appear to have staggered seasonal peaks of calling. In combination with interspecific variation in the meteorological correlates of calling, these results may be indicative of temporal partitioning of reproductive activity to facilitate coexistence, as has been reported for tropical and temperate anurans from other parts of the globe.
The ‘Policy Mix’ for Sustainable Urban Transition: The city district of Hammarby Sjöstad in Stockholm
Authors: Mahzouni Arian
Published: August 2015

This paper analyses the policy mix for urban transition by drawing on insights from studies in institutions and path dependence. It sheds new light on the role of institutions and actors in creating a policy mix for sustainable city districts, which has not been systematically addressed in the current debate on policy mix. The interaction and trade‐offs between policy instruments for energy efficiency in buildings in the city district of Hammarby Sjöstad are analysed historically. The key findings are that long periods of increasing returns in existing technological systems and the institutions that have supported them have created different types of ‘lock‐ins’ (behavioural, policy and industry). A systemic approach to developing a framework for policy mix analysis is necessary to address the relationship between various ‘lock‐ins’. © 2015 The Authors. Environmental Policy and Governance published by ERP Environment and John Wiley & Sons Ltd
Calix[6]arene Functionalized at Four Bridges: Conformation and Intramolecular Guest Exchange
Authors: Leader Avia , Itzhak Norbert , Bogoslavsky Benny , Biali Silvio E.
Published: August 2015

Reaction of the tert‐butoxycarbonyl derivative of p‐tert‐butylcalix[6]arene (2) with excess NBS under irradiation yields a calixarene with four bromomethine bridges as the major product (3). On the basis of the number of signals in the NMR spectrum, to the product was assigned a 1,2,4,5‐substitution pattern. X‐ray crystallography indicates that the product possesses the rct2 configuration and crystallized as a mixture of two conformers. The major form in the crystal exists in a 1,2,3‐alternate conformation where a single tert‐butoxycarbonyl group is self‐included in the cavity and all bromines are located at equatorial positions. A rotational barrier of 18.4 kcal mol–1 was measured for the intramolecular guest exchange rotational process that involves the mutual exchange between the unique self‐included Boc group and the Boc group on the opposite ring (Boc = tert‐butoxycarbonyl).
Assessment of global linear stability analysis using a time‐stepping approach for compressible flows
Authors: Ohmichi Y. , Suzuki K.
Published: August 2015

Global linear stability analysis combined with computational fluid dynamics (CFD) is considered useful for understanding the physics of fluid flows. However, the numerical techniques of global linear stability analysis for compressible flows have not been well established in comparison with those for incompressible flows. In this study, we develop and assess a set of appropriate numerical techniques required to conduct a global linear stability analysis for compressible flows. For the eigensystem analysis, the Arnoldi method combined with time integration is in effect to preserve the memory (RAM) size of the computer. The compact difference scheme is used for the CFD analysis from the viewpoints of computing accurate global modes and saving memory by reducing the number of grid points to obtain the necessary spatial resolution. To assess the proposed method, two‐dimensional compressible flow problems, including regularized cavity flow, flow around a square cylinder, and the compressible mixing layer, are analyzed, and it is confirmed that the proposed method can obtain accurate mode shapes, growth rate, and frequency of the corresponding global modes. In addition, influences and an appropriate formulation of the outflow boundary conditions are investigated. Results reveal that the outflow boundary causes spurious unstable modes in the global linear stability analysis, and the radiation and outflow boundary condition and the extension of the computational domain with grid stretching keep the spurious unstable modes to a minimum. Copyright © 2015 John Wiley & Sons, Ltd.
A study of reduced‐order 4DVAR with a finite element shallow water model
Authors: Altaf M. U. , Ambrozic M. , McCabe M. F. , Hoteit I.
Published: August 2015

Four‐dimensional variational data assimilation (4DVAR) is frequently used to improve model forecasting skills. This method improves a model consistency with available data by minimizing a cost function measuring the model–data misfit with respect to some model inputs and parameters. Associated with this type of method, however, are difficulties related to the coding of the adjoint model, which is needed to compute the gradient of the 4DVAR cost function. Proper orthogonal decomposition (POD) is a model reduction method that can be used to approximate the gradient calculation in 4DVAR. In this work, two ways of using POD in 4DVAR are presented, namely model‐reduced 4DVAR and reduced adjoint 4DVAR (RA‐4DVAR). Both techniques employ POD to obtain a reduced‐order approximation of the forward linear tangent operator. The difference between the two methods lies in the treatment of the forward model. Model‐reduced 4DVAR performs minimization entirely in the POD‐reduced space, thereby achieving very low computational costs, but sacrificing accuracy of the end result. On the other hand, the RA‐4DVAR uses POD to approximate only the adjoint model. The main contribution of this study is a comparative performance analysis of these 4DVAR methodologies on a nonlinear finite element shallow water model. The sensitivity of the methods to perturbations in observations and the number of observation points is examined. The results from twin experiments suggest that the RA‐4DVAR method is easy to implement and computationally efficient and provides a robust approach for achieving reasonable results in the context of variational data assimilation. Copyright © 2015 John Wiley & Sons, Ltd.
Methyltransferase expression and tumor suppressor gene methylation in sporadic and familial colorectal cancer
Authors: Joensuu Emmi I. , Nieminen Taina T. , Lotsari Johanna E. , Pavicic Walter , Abdel‐Rahman Wael M. , Peltomäki Päivi
Published: August 2015

Molecular mechanisms underlying coordinated hypermethylation of multiple CpG islands in cancer remain unclear and studies of methyltransferase enzymes have arrived at conflicting results. We focused on DNMT1 and DNMT3B, DNA methyltransferases responsible for (de novo) methylation, and EZH2, histone (H3K27) methyltransferase, and examined their roles in tumor suppressor gene (TSG) methylation patterns we have previously established in sporadic and familial cancers. Our investigation comprised 165 tumors, stratified by tissue of origin (117 colorectal and 48 endometrial carcinomas) and sporadic vs. familial disease (57 sporadic vs. 60 familial, mainly Lynch syndrome, colorectal carcinomas). By immunohistochemical evaluation, EZH2 protein expression was associated with a TSG methylator phenotype. DNMT1, DNMT3B, and EZH2 were expressed at significantly higher levels in tumor vs. normal tissues. DNMT1 and EZH2 expression were positively correlated and higher in microsatellite‐unstable vs. microsatellite‐stable tumors, whether sporadic or hereditary. Ki‐67 expression mirrored the same pattern. Promoter methylation of the methyltransferase genes themselves was addressed as a possible cause behind their altered expression. While DNMT1 or EZH2 did not show differential methylation between normal and tumor tissues, DNMT3B analysis corroborated the regulatory role of a distal promoter region. Our study shows that methyltransferase expression in cancer depends on the tissue of origin, microsatellite‐instability status, cellular proliferation, and—in the case of DNMT3B—promoter methylation of the respective gene. Translation of methyltransferase expression into DNA methylation appears complex as suggested by the fact that except for EZH2, no clear association between methyltransferase protein expression and TSG methylation was observed. © 2015 Wiley Periodicals, Inc.
Lower cognitive performance and white matter changes in testicular cancer survivors 10 years after chemotherapy
Authors: Stouten‐Kemperman Myrle M. , de Ruiter Michiel B. , Caan Matthan W.A. , Boogerd Willem , Kerst Martijn J. , Reneman Liesbeth , Schagen Sanne B.
Published: August 2015

Objective

Chemotherapy (CT) is associated with adverse effects on cognition. Only few studies have investigated cognition in testicular cancer (TC) patients and studies on very late effects of CT on cognition are absent. Further, brain changes in relation to treatment have not been investigated in TC. The objective of the present study is to compare psychosocial functioning, cognitive performance and brain (micro)structure following surgery and CT for TC, against surgery (S)‐only.

Methods

Twenty‐eight CT (43.1 ± 7.5 y) and 23 S‐only (48.2 ± 9.5y) TC survivors on average 14 yr post‐treatment were examined using questionnaires, neurocognitive tests, and 3T‐MRI [Diffusion Kurtosis Imaging (DKI), T1‐weighted and Fluid Attenuated Inversion Recovery]. A multivariate cognitive performance score (Mahalanobis distance) was calculated to indicate the grade of cognitive performance. Kurtosis parameters, gray matter, and white matter (WM) volume were calculated from MRI data.

Results

Overall, the CT group showed lower cognitive performance (5.35 ± 1.7) compared with the S‐only group (4.4 ± 0.9; P =0.03; d = 0.70). Further, TC patients reported more memory problems after CT. DKI revealed a significantly higher radial kurtosis after CT in several anterior and posterior brain areas (P < 0.05, corrected), but this was unrelated to cognitive performance.

Conclusions

This cross‐sectional study suggests that men receiving CT for TC are at risk for long‐term lower cognitive performance. Although CT affected WM microstructure, this was unrelated to cognitive performance. More extensive, preferably prospective studies are warranted to confirm these results and to provide more insight into the possible mechanisms behind the observed cognitive sequelae after treatment for TC. Hum Brain Mapp 36:4638–4647, 2015. © 2015 Wiley Periodicals, Inc.
The Impact of Ethical Leadership on Employees’ In‐Role Performance: The Mediating Effect of Employees’ Psychological Ownership
Authors: Park Cho Hyun , Kim Woocheol , Song Ji Hoon
Published: August 2015

The aim of the current research was to identify the influences of ethical leadership on employees’ in‐role performance in the Korean public nonprofit agency setting. The mediating effect of employees’ psychological ownership was also examined. A total of 202 responses were analyzed using the structural equation modeling (SEM) approach to test study hypotheses. Results showed that while the level of ethical leadership significantly impacts employees’ psychological ownership, ethical leadership has a significant indirect impact on in‐role performance only through employees’ psychological ownership. These results support the mediating role of the level of employees’ psychological ownership in explaining the relationship between ethical leadership and in‐role performance levels of employees. Research limitations and implications are discussed and future research directions are suggested.
The impact of caffeine on connexin expression in the embryonic chick cardiomyocyte micromass culture system
Authors: Ahir Bhavesh K. , Pratten Margaret K.
Published: August 2015

Cardiomyocytes are electrically coupled by gap junctions, defined as clusters of low‐resistance multisubunit transmembrane channels composed of connexins (Cxs). The expression of Cx40, Cx43 and Cx45, which are present in cardiomyocytes, is known to be developmentally regulated. This study investigates the premise that alterations in gap junction proteins are one of the mechanisms by which teratogens may act. Specifically, those molecules known to be teratogenic in humans could cause their effects via disruption of cell‐to‐cell communication pathways, resulting in an inability to co‐ordinate tissue development. Caffeine significantly inhibited contractile activity at concentrations above and including 1500 μm (P < 0.05), while not affecting cell viability and total protein, in the embryonic chick cardiomyocyte micromass culture system. The effects of caffeine on key cardiac gap junction protein (Cx40, Cx43 and Cx45) expression were analysed using immunocytochemistry and in‐cell Western blotting. The results indicated that caffeine altered the expression pattern of Cx40, Cx43 and Cx45 at non‐cytotoxic concentrations (≥2000 μm), i.e., at concentrations that did not affect total cell protein and cell viability. In addition the effects of caffeine on cardiomyocyte formation and function (contractile activity score) were correlated with modulation of Cxs (Cx40, Cx43 and Cx45) expression, at above and including 2000 μm caffeine concentrations (P < 0.05). These experiments provide evidence that embryonic chick cardiomyocyte micromass culture may be a useful in vitro method for mechanistic studies of perturbation of embryonic heart development. Copyright © 2015 John Wiley & Sons, Ltd.
Cortisol, HDL‐c, VLDL‐c, and APOE Polymorphisms as Laboratorial Parameters Associated to Cognitive Impairment No Dementia (CIND) and Dementia
Authors: Lara Vivian P. , Caramelli Paulo , Teixeira Antônio L. , Barbosa Maira T. , Carmona Karoline C. , Guimarães Henrique C. , Carvalho Maria G. , Fernandes Ana P. , Gomes Karina B.
Published: August 2015

Background

Population aging is a global phenomenon whose main consequence is the increase of chronic degenerative diseases, including dementia. The aim of this case–control study was to evaluate the laboratorial parameters lipid profile, cortisol, and apolipoprotein E (APOE) gene genotype, comparing cognitively healthy controls and subjects with cognitive impairment no dementia (CIND) and dementia in a group of elderly people.

Methods

Three hundred and nine individuals enrolled in the Pietà Study (Brazil) were divided into three groups: control (n = 158), CIND (n = 92), and dementia (n = 59). Participants were interviewed, went through examination, and had blood samples taken.

Results

Age and APOE showed significant differences among the groups, while sex and lipid profile did not. According to multivariate regression logistic analyses, higher cortisol levels, lower high‐density lipoprotein (HDL‐c) and very low‐density lipoprotein (VLDL‐c), presence of ε4 allele of APOE, and aging were associated with CIND and dementia.

Conclusion

These laboratorial parameters are risk factors associated to CIND and dementia in the elderly people and should be investigated in order to develop strategies to prevent or delay the onset of dementia in the oldest‐old populations.
Fasting Lipoprotein Lipase Protein Levels Can Predict a Postmeal Increment of Triglyceride Levels in Fasting Normohypertriglyceridemic Subjects
Authors: Tsuzaki Kokoro , Kotani Kazuhiko , Yamada Kazunori , Sakane Naoki
Published: August 2015

Background

Although a postprandial increment in triglyceride (TG) levels is considered to be a risk factor for atherogenesis, tests (e.g., fat load) to assess postprandial changes in TG levels cannot be easily applied to clinical practice. Therefore, fasting markers that predict postprandial TG states are needed to be developed. One current candidate is lipoprotein lipase (LPL) protein, a molecule that hydrides TGs. This study investigated whether fasting LPL levels could predict postprandial TG levels.

Methods

A total of 17 subjects (11 men, 6 women, mean age 52 ± 11 years) with normotriglyceridemia during fasting underwent the meal test. Several fasting parameters, including LPL, were measured for the area under the curve of postprandial TGs (AUC‐TG).

Results

The subjects’ mean fasting TG level was 1.30 mmol/l, and their mean LPL level was 41.6 ng/ml. The subjects’ TG levels increased after loading (they peaked after two postprandial hours). Stepwise multiple regression analysis demonstrated that fasting TG levels were a predictor of the AUC‐TG. In addition, fasting LPL mass levels were found to be a predictor of the AUC‐TG (β = 0.65, P < 0.01), and this relationship was independent of fasting TG levels.

Conclusion

Fasting LPL levels may be useful to predict postprandial TG increment in this population.
Performance Evaluation of Three URiSCAN Devices for Routine Urinalysis
Authors: Ko Kiwoong , Kwon Min‐Jung , Ryu Seungho , Woo Hee‐Yeon , Park Hyosoon
Published: August 2015

Background

This study compares the diagnostic performance (in routine urinalysis) of three URiSCAN devices and three Roche analyzers to manual microscopy and quantitative assays.

Methods

We analyzed eight dipstick tests using three URiSCAN devices. The results were compared to those of the tests performed using three Roche analyzers. The results of leukocyte and erythrocyte screens were compared to those obtained using manual microscopy. Protein, glucose, pH, and specific gravity (SG) assays performed on the URiSCAN devices were compared with the results of corresponding quantitative assays.

Results

The rates of agreement within one grade difference were found to be more than 94.3%. When compared with manual microscopy, the Optima provided better diagnostic performance for the detection of leukocytes compared with the Urisys 1100. Compared to the Urisys 2400, the Super plus provided better diagnostic performance with regard to both leukocytes and erythrocytes. There was good correlation between the three URiSCAN devices and each quantitative assay, except for SG detection.

Conclusion

There were well correlated results between those of the three URiSCAN devices and those obtained using the corresponding Roche analyzers, quantitative assays, and manual microscopy. URiSCAN series devices are therefore suitable for routine urinalysis in clinical laboratories.
Botanical features for identification of Gymnosporia arenicola dried leaf
Authors: Da Silva Gustavo , Serrano Rita , Teixeira Gomes Elsa , Silva Olga
Published: August 2015

Gymnosporia arenicola Jordaan (Celastraceae) is a shrub or small tree, which naturally occurs in coastal sand dunes of Southern Mozambique and South Africa. Its dried leaf is often used in traditional medicine for the treatment of infectious and inflammatory diseases. Hereby, we present results of studies carried out according to the pharmacopoeia standards for the identification of herbal drugs, in the whole, fragmented, and powdered plant material. These results were complemented with scanning electron microscopy and histochemical techniques. The leaf microscopic analysis revealed a typical dorsiventral mesophyll with a corresponding spongy parenchyma–palisade parenchyma ratio of 0.60, anomocytic and paracytic stomata, papillate cells with a diameter of 4.00 ± 0.40 µm, multicellular uniseriate nonglandular trichomes with a length of 27.00 ± 4.10 µm and cristalliferous idioblasts containing calcium oxalate cluster crystals with a diameter of 23.04 ± 5.84 µm. The present findings demonstrate that the G. arenicola leaf has both nonglandular trichomes and hypoderm, features not previously described in the corresponding botanical section (Gymnosporia sect. Buxifoliae Jordaan). The establishment of these new botanical markers for the identification of G. arenicola leaf is essential for quality, safety and efficacy reasons. Microsc. Res. Tech. 78:1001–1009, 2015. © 2015 Wiley Periodicals, Inc.
Internal Partitions of Regular Graphs
Authors: Ban Amir , Linial Nati
Published: August 2015

An internal partition of an n‐vertex graph is a partition of V such that every vertex has at least as many neighbors in its own part as in the other part. It has been conjectured that every d‐regular graph with vertices has an internal partition. Here we prove this for . The case is of particular interest and leads to interesting new open problems on cubic graphs. We also provide new lower bounds on and find new families of graphs with no internal partitions. Weighted versions of these problems are considered as well.
Evaluation of apparent diffusion coefficient and MR volumetry as independent associative factors for extra‐prostatic extension (EPE) in prostatic carcinoma
Authors: Lim Christopher , Flood Trevor A. , Hakim Shaheed W. , Shabana Wael M. , Quon Jeffrey S. , El‐Khodary Mohamed , Thornhill Rebecca E. , El Hallani Soufiane , Schieda Nicola
Published: August 2015

Background

To assess mean apparent diffusion coefficient (ADC) and MR‐derived tumor volume (Vt) as associative factors for extra‐prostatic extension (EPE) in prostate cancer (PCa).

Methods

With institutional review board approval, 73 consecutive patients diagnosed with PCa at trans‐rectal ultrasound biopsy underwent preoperative multi‐parametric (T2W+DWI+DCE) 3 Tesla MRI before radical prostatectomy between 2012 and 2014; 52% (38/73) patients had EPE. Clinical parameters including: age, prostate serum antigen (PSA), digital rectal examination (DRE) and percentage positive cores (PPC) were recorded. Two blinded radiologists subjectively evaluated for EPE using PI‐RADS with T2W‐MRI. A third blinded radiologist recorded: mean ADC (mm2/s) of tumor and tumor volume on ADC and T2W (derived from planar volumetry). VtMAX (the largest volume on ADC or T2W) was documented. Multivariate and receiver operator characteristic analyses were performed.

Results

There were no significant differences in age, DRE, or Gleason score between groups (P = 0.52, 0.06, 0.61, 0.36). PSA approached significance being higher with EPE (12.9 ± 12.6 versus 8.2 ± 7.4; P = 0.06). PPC was higher with EPE (60.9 ± 21.9% versus 38.3 ± 21.6%; P < 0.01) with an area under the curve (AUC) of 0.78 and sensitivity/specificity = 75.7/75% when PPC ≥ 45%. AUC for T2W‐MRI was 0.46–0.51 with sensitivity/specificity = 40.0–42.9/48.6–57.1% (R1, R2). Inter‐observer agreement was fair, k = 0.39. There was no difference in mean ADC between groups (0.89 ± 0.25 versus 0.88 ± 0.19 [EPE] mm2/s), P = 0.70. T2W‐Vt, ADC‐Vt, and VtMAX were larger with EPE (5.1 ± 7.4, 5.8 ± 6.5, 6.3 ± 7.4 cm3 versus 1.6 ± 1.8, 1.8 ± 1.3, 2.1 ± 1.8), P < 0.01. VtMAX AUC was 0.77 with sensitivity/specificity = 78.4/73.5% when VtMAX ≥ 2.1 cm3 which outperformed all other parameters (P > 0.05) except PPC (P = 0.6) for the diagnosis EPE.

Conclusion

MR volumetry and percentage of positive core biopsies are associated with EPE; whereas, in this study, other clinical and MR parameters including mean ADC and subjective T2W‐MR analysis were not useful for assessment of EPE. J. MAGN. RESON. IMAGING 2016;43:726–736.
Pacific Ocean SST and Z500 climate variability and western U.S. seasonal streamflow
Authors: Sagarika Soumya , Kalra Ajay , Ahmad Sajjad
Published: August 2015

The current study focuses on evaluating the relationship between the Pacific Ocean climate variability and western US streamflow for six hydrologic regions of the western United States, as defined by United States Geological Survey: Rio Grande, Upper Colorado, Lower Colorado, Great Basin, Pacific Northwest, and California. The singular‐valued decomposition (SVD) technique was applied on data for 50 years (1960–2010) of sea‐surface temperatures (SST), geopotential height index of 500 mbar (Z500), and 90 unimpaired western US streamflows; the results established a spatio‐temporal association for each major hydrologic region in the western United States with Pacific Oceanic variability. An approach using a 3‐ to 9‐month lead time was utilized, i.e. the previous year's July to August SST/Z500, the previous year's October to December SST/Z500 to predict streamflow for current year spring–summer (April to September), spring (April to June), and summer (July to September) seasons. Significant regions in the Pacific were identified that influence hydrology of the western United States. The traditional El Niño/Southern Oscillation (ENSO) and Pacific Decadal Oscillation regions were identified along with regions over eastern Russia, Canadian British Columbia, and the ‘Hondo’ region along the east coast of Japan. Z500 showed pronounced association with 3‐month lead time streamflow, whereas SST had better association with 6‐month lead time streamflow. The SVD results showed improvement in correlation values of smaller spatial regions over larger regions, and a lagged response of adjacent hydrologic regions to the same physical indicators. The results obtained in this study could be helpful in improving the current forecasting models for water management.
A population‐based assessment of melanoma: Does treatment in a regional cancer center make a difference?
Authors: Rivard Justin , Kostaras Xanthoula , Shea‐Budgell Melissa , Chin‐Lenn Laura , Quan May Lynn , McKinnon J. Gregory
Published: August 2015

Background

Regionalization of care to specialized centers has improved outcomes for several cancer types. We sought to determine if treatment in a regional cancer center (RCC) impacts guideline adherence and outcomes for patients with melanoma.

Methods

In Alberta, Canada, 561 patients with stage I–IIIC primary melanoma were diagnosed between January 2009 and December 2010. The electronic health record was used to capture demographic and pathologic data. Provincial guidelines for sentinel lymph node biopsy (SLNB) and wide local excision (WLE) are based on recommendations of several pre‐existing guidelines including the National Comprehensive Cancer Network.

Results

148 of 561 patients were identified as having been treated at a RCC. Median follow‐up was 45 months. Patients treated at the RCC presented with higher stage melanomas. The RCC was more likely to follow guideline recommendations for performing SLNB (81.3% vs. 55.4%, P < 0.0001) but not for the extent of WLE (76.6% vs. 84.1%, P = 0.054). Overall survival was impacted by tumor thickness (HR 1.14, P < 0.0001), ulceration (HR 5.58, P < 0.0001), and mitoses (HR 0.59, P = 0.05).

Conclusions

The RCC more closely followed guidelines for SLNB but not for WLE. Despite patients treated at the RCC presenting with a more advanced stage, overall survival and disease‐free survival appear to not be affected by treatment center. J. Surg. Oncol. 2015 111:173–178. © 2015 Wiley Periodicals, Inc.
Surgery of gastric cancer and esophageal cancer: Does age matter?
Authors: Nienhueser Henrik , Kunzmann Romy , Sisic Leila , Blank Susanne , Strowitzk Moritz J. , Bruckner Thomas , Jäger Dirk , Weichert Wilko , Ulrich Alexis , Büchler Markus W. , Ott Katja , Schmidt Thomas
Published: August 2015

Introduction

In the past, elderly patients with upper GI cancers were excluded from surgery or multimodal treatment only due to their advanced age. In an aging society this way of patient selection seems to be questionable. The aim of this retrospective exploratory study was to investigate how patients with upper GI cancer over the age of 70 years differ from younger patients in the postoperative course and which parameters influence overall survival in older patient populations.

Patients and Methods

From 2002 to 2012 1,005 patients underwent resection of esophageal or gastric cancer at the University of Heidelberg. 272 patients were older than 70 years and analyzed in subgroups (70–74 years: n = 146; 75–79 years: n = 82; 80 years or older: n = 44). Patients older than 70 years were compared to patients under 70 years (n = 733) with focus on differences in patients characteristics and outcome. Statistical analyses were made retrospectively on a prospective database.

Results

Fewer older patients were treated neoadjuvantly (< 70 years: 41.5%; > 70 years: 24.7%, P < 0.001) and extended resection (abdominothoracic approach) was applied less frequently compared to patients under 70 years (< 70 years: 38.9%; > 70 years: 19.9%, P < 0.001). The pNM‐category (HR 1.41/2.56) and R‐status (HR 1.78) remain the most important predictive factor for survival (all < 0.001). Female patients had a longer survival than men over the age of 70 (84.9 vs. 23.5 months, P < 0.01). Patients over 80 years had a significant shortened overall survival (> 80 years: 16.7 vs. < 70 years: 37.4 months) compared to the other subgroups (P < 0.001) and a significant increased in‐hospital mortality (> 80 years: 20.5% vs. < 70 years: 6.0%, P = 0.002).

Conclusions

An exclusion from surgical therapy due to advanced age in general seems not to be justified. However, the decision for a surgical resection in patients over 80 years should be made with caution. pNM‐categories and R0‐resection remain the most important predictive factors for overall survival in all subgroups. No survival benefit for neoadjuvant treatment in patients over 70 years was found, while women survived longer than men. However, the decision concerning a (radio) chemotherapy should be made individually in each patient. J. Surg. Oncol. 2015; 112:387–395. © 2015 Wiley Periodicals, Inc.
Optimization of an accelerated solvent extraction dispersive liquid–liquid microextraction method for the separation and determination of essential oil from Ligusticum chuanxiong Hort by gas chromatography with mass spectrometry
Authors: Yang Guang , Sun Qiushi , Hu Zhiyan , Liu Hua , Zhou Tingting , Fan Guorong
Published: August 2015

In this study, an accelerated solvent extraction dispersive liquid–liquid microextraction coupled with gas chromatography and mass spectrometry was established and employed for the extraction, concentration and analysis of essential oil constituents from Ligusticum chuanxiong Hort. Response surface methodology was performed to optimize the key parameters in accelerated solvent extraction on the extraction efficiency, and key parameters in dispersive liquid–liquid microextraction were discussed as well. Two representative constituents in Ligusticum chuanxiong Hort, (Z)‐ligustilide and n‐butylphthalide, were quantitatively analyzed. It was shown that the qualitative result of the accelerated solvent extraction dispersive liquid–liquid microextraction approach was in good agreement with that of hydro‐distillation, whereas the proposed approach took far less extraction time (30 min), consumed less plant material (usually <1 g, 0.01 g for this study) and solvent (<20 mL) than the conventional system. To sum up, the proposed method could be recommended as a new approach in the extraction and analysis of essential oil.
Insights Gained by Modeling the Kinetics of Archetypal Hydrogen Atom Transfer Reactions: NH3 + ·H ⇆ H2N· + H2 and CH4 + ·H ⇆ H3C· + H2
Authors: Zavitsas Andreas A.
Published: August 2015

Experimental measurements of the kinetics of the title reactions extend to temperature ranges of 1360 K for the ammonia‐hydrogen reaction and of 1602 K for the methane‐hydrogen reaction. Curved plots of ln(k) versus 1/T are obtained. Many theoretical calculations modeling these reactions routinely use tunneling corrections to match experiment. The steepness and curvatures of the plots are modeled successfully in this work and are shown to be caused solely by changes in the bond dissociation energies of the bonds involved in the reactions without invoking tunneling or any other adjustable parameters. The conclusion that tunneling does not contribute significantly to the rates in the temperature range of the measurements is in stark contrast with those theoretical calculations invoking large tunneling factors in the experimental temperature range. Support for the conclusion is provided by theoretical calculations of harmonic quantum transition state theory implementing instanton theory. There is direct experimental evidence that significant tunneling occurs in some H atom transfers, as with isotopomers of H2 + ·H and other H transfers at very low temperatures. However, there is no direct experimental evidence of significant tunneling contributions to the rates of the title reactions in the temperature range of the measurements. Insights are gained into what specific forces must be overcome by the enthalpy of activation for reaction to occur.
Multiscale Control of Hierarchical Structure in Crystalline Block Copolymer Nanoparticles Using Microfluidics
Authors: Bains Aman , Cao Yimeng , Moffitt Matthew G.
Published: August 2015

Hierarchical semicrystalline block copolymer nanoparticles are produced in a segmented gas‐liquid microfluidic reactor with top‐down control of multiscale structural features, including nanoparticle morphologies, sizes, and internal crystallinities. Control of multiscale structure on disparate length scales by a single control variable (flow rate) enables tailoring of drug delivery nanoparticle function including release rates.

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Formulation and Characterization of New pH Dependent [Alizarin‐poly(4‐vinylpyridine)‐mica] Pigments
Authors: Mansri Ali , Dergal Fayçal , Billon Laurent
Published: August 2015

We formulate for the first time new [Alizarin‐poly(4‐vinylpyridine)‐mica] inorganic@organic pH dependent pigmentary materials. The present formulation is carried out via two steps: (i) the preparation by adsorption of poly(4‐vinylpyridine) [P4VP] on mica particles, of two hybrid composite materials [P4VP@Mica], with respectively ratios R = 0.2 and R = 0.5; (ii) the formulation of new pigmentary materials by fixation of Alizarin dyes on [P4VP@Mica] composite materials. The composite materials [P4VP@Mica] were characterized using, Thermogravimetric analysis (TGA), Fourier transformed infrared (IRTF), Scanning Electron Microscopy coupled with Energy dispersive X‐Ray Spectroscopy (SEM‐EDX) and UV‐visible. The adsorbed polymers on the inorganic surface have a potential interest for the modification of the interfacial properties of the MICA. These new pigmentary materials can either differ by their colors, or to present interferential effects.
Synthesis, Processing and Tensile Testing of a Poly(l‐lactide‐co‐caprolactone) Monofilament Fiber for Use as an Absorbable Surgical Suture
Authors: Ruengdechawiwat Sujitra , Molloy Robert , Siripitayananon Jintana , Somsunan Runglawan , Topham Paul D. , Tighe Brian J.
Published: August 2015

Summary A poly(l‐lactide‐co‐caprolactone), P(LL‐co‐CL), 75:25 mol % copolymer was synthesized via the bulk ring‐opening copolymerization of l‐lactide (LL) and ϵ‐caprolactone (CL) at 130 °C for 48 hrs. The P(LL‐co‐CL) copolymer obtained was characterized in terms of its molecular weight (GPC), copolymer composition (1H‐NMR), monomer sequencing (13C‐NMR) and thermal properties (DSC, TGA). For processing, the P(LL‐co‐CL) was melt spun into a monofilament fiber with fast cooling and minimal draw in order to produce an as‐spun fiber that was largely amorphous and unoriented. This enabled the required oriented semi‐crystalline morphology to be gradually built into the as‐spun fiber in a series of controlled off‐line annealing and hot‐drawing steps. The final fiber, which combined sufficient tensile strength with flexibility for use as a suture material, exhibited a stress and strain at break of 344 MPa and 70%, respectively.
Reactive ABA‐Type Triblock Phospholipid Copolymer by ATRP and Its Chemical Functionalizations
Authors: Chantasirichot Surasak , Inoue Yuuki , Ishihara Kazuhiko
Published: August 2015

Reactive ABA‐type triblock phospholipid copolymers composed of poly(glycidyl methacrylate) (PGMA) as A segments and poly(2‐methacryloyloxyethyl phosphorylcholine) (PMPC) as B segments (PGMA‐block‐PMPC‐block‐PGMA (PMbG)) were synthesized via controlled/living polymerization. The PMPC moiety was hydrophilic and water‐soluble while PGMA containing an epoxide ring worked as the reactive group for interaction with the nucleophiles. These reactions provided a facile route to modify the copolymer for desired functions. In this study, we synthesized phenylboronic acid‐containing (PMbB) and diethanolamine‐containing (PMbD) copolymers by functionalizing PMbG. PMbB and PMbD spontaneously formed stable hydrogels in aqueous media without any external stimuli. Owing to the excellent biocompatibility of the PMPC segments and easy functionalization of the PGMA segments, these reactive triblock phospholipid polymers can prove useful in various biomedical applications.
Potentiometric Urea Biosensor Based on a Urease‐Immobilized Polypyrrole
Authors: Prissanaroon‐Ouajai Walaiporn , Sirivat Anuvat , Pigram Paul J. , Brack Narelle
Published: August 2015

Urea is one of the metabolic products of protein metabolism. The accurate determination of urea is important in glomerular filtration rate determination, renal function testing, and other biomedical applications. This research presents a simple fabrication of potentiometric urea biosensor based on a urease‐immobilized polypyrrole (PPy). Thin film of PPy doped with hydroquinone monosulfonate (HQS) was electropolymerized on stainless steel supporting electrode. Urease was immobilized onto the PPy film by mean of physical adsorption. X‐ray photoelectron spectroscopy (XPS) was performed to confirm the existence of urease on PPy surface. The PPy film immobilized with urease activity of 200 U/mL showed the sensitivity of 43.4 ± 3.3 mV/pUrea (r2 > 0.99) in the urea concentration ranging from 0.5 to 10 mM (pUrea 2.0–3.3). The response time was less than 60 sec. The urease‐immobilized PPy film offers a great potential in the use of conducting PPy film as an effective transducer to convert physiochemical change into an electronic signal, enhancing in performance of the biosensor.
Surface Modification on Poly(ether ether ketone) with Phospholipid Polymer via Photoinduced Self‐Initiated Grafting
Authors: Ishihara Kazuhiko , Inoue Yuuki , Kyomoto Masayuki
Published: August 2015

A new and safer method for constructing a nanometer‐scale modified surface on the poly(ether ether ketone) (PEEK) is examined by “photoinduced self‐initiated graft polymerization”. The generation of semi‐benzopinacol‐containing radicals of the benzophenone units in PEEK molecular structure acted as a photoinitiator. This polymerization system is realized in the absence of a photoactive low molecular compound and in an aqueous medium; these are human‐friendly and exhibit excellent biocompatibility. In this study, we demonstrated the fabrication of modified surface with phospholipid polymer, i.e., poly(2‐methacryloyloxyethyl phosphorylcholine) (PMPC) using the photoinduced self‐initiated graft polymerization process. Effects of MPC concentration in the reacting solution and intensity of UV irradiation on the surface properties were examined. On the surface on PMPC‐graft‐PEEK, a significant reduction in the protein adsorption was observed. We conclude that the smart PMPC‐graft‐PEEK prepared by the photoinduced self‐initiated graft polymerization to produce PMPC layer on the surface will bring novel biomedical devices with both good mechanical property and biocompatible surface.
Quantitative Analysis of Total Phenolic Contents and Antioxidant Activity of Fresh Field Natural Rubber Latex
Authors: Siriwong Suwimon , Rungvichaniwat Adisai , Klinpituksa Pairote , Musa Khalid Hamid , Abdullah Aminah
Published: August 2015

Dried films of fresh field natural rubber latex from Pattani local rubber plantation, Thailand were prepared. The film (1g) was dissolved by various solvent (100ml) i.e. hexane, chloroform and mixtures of chloroform: methanol in the ratio of 1:1, 2:1 and 4:1. The solution was purified by separated the rubber out with methanol. The non‐rubber solution was then quantitative analyzed to verify total phenolic content (TPC), ferric reducing antioxidant power (FRAP) and DPPH radical scavenging activity using Oxicount Antioxidant kit test. It was found that only hexane, chloroform and mixture of chloroform: methanol of ratio 4:1 can dissolve rubber film completely. The non‐rubber content yields after evaporated solvent were 8.23 ± 0.05, 8.93 ± 0.81 and 11.56 ± 0.01%, TPCs were 226.18 ± 8.60, 230.91 ± 15.66 and 233.71 ± 12.44 milligrams of gallic acid equivalent (GAE) per 100 g of initial weight (IW) and FRAP were 153.04 ± 13.75, 178.43 ± 10.37 and 189.04 ± 1.34 milligrams of Trolox equivalents (TE) per 100 g of IW, the percentage of DPPH radical scavenging activity were 88.32 ± 0.99, 91.48 ± 0.86 and 92.42 ± 0.05%, respectively. This study found that TPC and antioxidant activity of rubber film clearly depend on the type of dissolved solvent. The highest antioxidant activity from this study was found by using the mixture of chloroform: methanol in the ratio of 4:1. Furthermore, the phenolic acid content of natural rubber were reported using HPLC, based on which more phenolic acids were presented in the sample extracted by chloroform:methanol mixture.
Preparation of Dichlorocarbene Modified Butadiene Rubber and Its Thermal Properties
Authors: Witinuntakit Tapanee , Poompradub Sirilux
Published: August 2015

Dichlorocarbene modified butadiene rubber (DCBR) was prepared from butadiene rubber (BR) via an alkali hydrolysis of chloroform with using cetyltrimetylammonium bromide (CTAB) as a phase transfer agent. The chemical structure of DCBR was characterized by a fourier transform infrared spectroscopy and 1H‐ and 13C‐nuclear magnetic resonance spectroscopy. The chlorine content in DCBR matrix was extracted by acid digestion method and estimated based on a volhard method. The chlorine content of DCBR increased with the increase of reaction time. The glass transition temperature (Tg) of DCBR (Tg = −3.4 °C) was shifted to the higher temperature compared to Tg value of BR (Tg = −102.8 °C) due to the presence of dichlorocarbene group. Moreover, thermogravimetric analysis was used to study the decomposition profile of BR and DCBR. The thermal stability of DCBR was decreased compared to that of BR, while the flame retardant of NR/DCBR blend was improved due to the presence of chlorine in DCBR. The chlorine char from dichlorocarbene group acted as a thermal insulator for rubber.
Preparation of Natural Rubber‐graft‐Poly(lactic acid) Used as a Compatibilizer for Poly(lactic acid)/NR Blends
Authors: Sookprasert Phijittra , Hinchiranan Napida
Published: August 2015

Poly(lactic acid) (PLA) is a biodegradable plastic with good properties in terms of high tensile strength and high tensile modulus, but the brittleness and low impact strength behavior limit its applications. To enhance the impact strength of PLA, natural rubber (NR) with excellent elastic property should be applied to PLA. However, the polarity difference of these constituents leads the incompatibility resulting in poor mechanical properties of PLA/NR blends. Thus, the chemical modification of NR to increase its polarity is required. This research aimed to synthesize NR‐graft‐PLA (NR‐PLA) as a compatibilizer for PLA/NR blends. There were 2 steps to prepare NR‐PLA compatibilizer. Firstly, NR was functionalized by various maleic anhydride (MAH) contents (5‐20 phr) to produce NR‐MAH having higher polarity than NR. Then, NR‐MAH was grafted with PLA via esterification using 4‐dimethyaminopyridine (DMAP) as a catalyst. The structural characterization of the NR‐MAH and NR‐PLA was conducted by FT‐IR and 1H NMR spectrooscopy. This was observed that the increase in the MAH contents increased the amount of grafted MAH in the NR‐MAH structure. The higher grafted MAH content induced the greater efficiency for grafting PLA in preparation of NR‐PLA. The effects of DMAP, NR/PLA wt ratio and temperature in the esterification step on the grafted PLA were investigated.