bluuebunny/crossref_metadata_2025 huggingface dataset:
Spectral fingerprints of large‐scale cortical dynamics during ambiguous motion perception
Authors: Helfrich Randolph F. , Knepper Hannah , Nolte Guido , Sengelmann Malte , König Peter , Schneider Till R. , Engel Andreas K.
Published: June 2016

Ambiguous stimuli have been widely used to study the neuronal correlates of consciousness. Recently, it has been suggested that conscious perception might arise from the dynamic interplay of functionally specialized but widely distributed cortical areas. While previous research mainly focused on phase coupling as a correlate of cortical communication, more recent findings indicated that additional coupling modes might coexist and possibly subserve distinct cortical functions. Here, we studied two coupling modes, namely phase and envelope coupling, which might differ in their origins, putative functions and dynamics. Therefore, we recorded 128‐channel EEG while participants performed a bistable motion task and utilized state‐of‐the‐art source‐space connectivity analysis techniques to study the functional relevance of different coupling modes for cortical communication. Our results indicate that gamma‐band phase coupling in extrastriate visual cortex might mediate the integration of visual tokens into a moving stimulus during ambiguous visual stimulation. Furthermore, our results suggest that long‐range fronto‐occipital gamma‐band envelope coupling sustains the horizontal percept during ambiguous motion perception. Additionally, our results support the idea that local parieto‐occipital alpha‐band phase coupling controls the inter‐hemispheric information transfer. These findings provide correlative evidence for the notion that synchronized oscillatory brain activity reflects the processing of sensory input as well as the information integration across several spatiotemporal scales. The results indicate that distinct coupling modes are involved in different cortical computations and that the rich spatiotemporal correlation structure of the brain might constitute the functional architecture for cortical processing and specific multi‐site communication. Hum Brain Mapp 37:4099–4111, 2016. © 2016 Wiley Periodicals, Inc.
A comprehensive genome‐wide analysis of melanoma Breslow thickness identifies interaction between CDC42 and SCIN genetic variants
Authors: Vaysse Amaury , Fang Shenying , Brossard Myriam , Wei Qingyi , Chen Wei V. , Mohamdi Hamida , Vincent‐Fetita Lynda , Margaritte‐Jeannin Patricia , Lavielle Nolwenn , Maubec Eve , Lathrop Mark , Avril Marie‐Françoise , Amos Christopher I. , Lee Jeffrey E. , Demenais Florence
Published: June 2016

Breslow thickness (BT) is a major prognostic factor of cutaneous melanoma (CM), the most fatal skin cancer. The genetic component of BT has only been explored by candidate gene studies with inconsistent results. Our objective was to uncover the genetic factors underlying BT using an hypothesis‐free genome‐wide approach. Our analysis strategy integrated a genome‐wide association study (GWAS) of single nucleotide polymorphisms (SNPs) for BT followed by pathway analysis of GWAS outcomes using the gene‐set enrichment analysis (GSEA) method and epistasis analysis within BT‐associated pathways. This strategy was applied to two large CM datasets with Hapmap3‐imputed SNP data: the French MELARISK study for discovery (966 cases) and the MD Anderson Cancer Center study (1,546 cases) for replication. While no marginal effect of individual SNPs was revealed through GWAS, three pathways, defined by gene ontology (GO) categories were significantly enriched in genes associated with BT (false discovery rate ≤5% in both studies): hormone activity, cytokine activity and myeloid cell differentiation. Epistasis analysis, within each significant GO, identified a statistically significant interaction between CDC42 and SCIN SNPs (pmeta‐int =2.2 × 10−6, which met the overall multiple‐testing corrected threshold of 2.5 × 10−6). These two SNPs (and proxies) are strongly associated with CDC42 and SCIN gene expression levels and map to regulatory elements in skin cells. This interaction has important biological relevance since CDC42 and SCIN proteins have opposite effects in actin cytoskeleton organization and dynamics, a key mechanism underlying melanoma cell migration and invasion.
OUTLINING THE WINDOWS OF ACHIEVEMENT OF INTERSUBJECTIVE MILESTONES IN TYPICALLY DEVELOPING TODDLERS
Authors: Sadurní Brugué Marta , Pérez Burriel Marc
Published: June 2016

Babies are born with an innate drive or intrinsic motive formation with which to communicate and share meanings with others and that some authors have called intersubjectivity (S. Bråten & C. Trevarthen, 2007; C. Trevarthen, 1974, 2001). Around the ninth month of life, this motivation changes and passes from a person‐to‐person dyadic (primary intersubjectivity) to a person–person–object relationship (secondary intersubjectivity). S. Bråten and C. Trevarthen (2007) also proposed a third form or layer of intersubjectivity known as tertiary intersubjectivity. One hundred fifteen free‐play sessions of 27 mother–child dyads (13 girls and 14 boys ages 9–37 months) were filmed and categorized using the Level of Intersubjective Attunement Scale (LISA‐T; M. Pérez Burriel & M. Sadurní Brugué, 2014; M. Sadurní Brugué & M. Pérez Burriel, 2012). Results from these nine hierarchical levels are presented, following a developmental sequence or population trajectory around an interindividual variability. In this article, we propose viewing these age‐related levels as windows of achievement of intersubjective milestones. The statistical analysis suggested a redesign of the LISA‐T levels of intersubjectivity; thus, results from this redesign and the debate on the implications of these transitions in infant mental health development are presented.
MOTHERS’ AND FATHERS’ PRENATAL REPRESENTATIONS IN RELATION TO MARITAL DISTRESS AND DEPRESSIVE SYMPTOMS
Authors: Ahlqvist‐Björkroth Sari , Korja Riikka , Junttila Niina , Savonlahti Elina , Pajulo Marjukka , Räihä Hannele ,   The steps study group, Aromaa Minna
Published: June 2016

Marital distress, parental depression, and weak quality of parental representations are all known risk factors for parent–child relationships. However, the relation between marital distress, depressive symptoms, and parents’ prenatal representation is uncertain, especially regarding fathers. The present study aimed to explore how mothers’ and fathers’ prenatal experience of marital distress and depressive symptoms affects the organization of their prenatal representations in late pregnancy. Participants were 153 pregnant couples from a Finnish follow‐up study called “Steps to the Healthy Development and Well‐being of Children” (H. Lagström et al., ). Marital distress (Revised Dyadic Adjustment Scale; D.M. Busby, C. Christensen, D. Crane, & J. Larson, 1995) and depressive symptoms (Edinburgh Postnatal Depression Scale) were assessed at 20 gestational weeks, and prenatal representations (Working Model of the Child Interview; D. Benoit, K.C.H. Parker, & C.H. Zeanah, 1997; C.H. Zeanah, D. Benoit, M. Barton, & L. Hirshberg, 1996) were assessed between 29 and 32 gestational weeks. The mothers’ risks of distorted representations increased significantly when they had at least minor depressive symptoms. Marital distress was associated with the fathers’ prenatal representations, although the association was weak; fathers within the marital distress group had less balanced representations. Coexisting marital distress and depressive symptoms were only associated with the mothers’ representations; lack of marital distress and depressive symptoms increased the likelihood for mothers to have balanced representations. The results imply that marital distress and depressive symptoms are differently related to the organizations of mothers’ and fathers’ prenatal representations.
The effect of chemically modified electrospun silica nanofiber on the mRNA and miRNA expression profile of neural stem cell differentiation
Authors: Mercado Augustus T. , Yeh Jui‐Ming , Chin Ting Yu , Chen Wen Shuo , Chen‐Yang Yui Whei , Chen Chung‐Yung
Published: June 2016

A detailed genomic and epigenomic analyses of neural stem cells (NSCs) differentiation in synthetic microenvironments is essential for the advancement of regenerative medicine and therapeutic treatment of diseases. This study identified the changes in mRNA and miRNA expression profile during NSC differentiation on an artificial matrix. NSCs were grown on a surface‐modified, electrospun tetraethyl‐orthosilicate nanofiber (designated as SNF‐AP) by providing a 3D‐environment for cell growth and differentiation. Differentially expressed mRNAs and miRNAs of NSC differentiated in this microenvironment were identified through microarray analysis. The genes and miRNA targets responsible for the differentiation fate of NSCs and neuron development process were determined using Ingenuity Pathway Analysis (IPA). SNF‐AP enhanced the expression of genes that activates the proliferation, development, and outgrowth of neurons, differentiation and generation of cells, neuritogenesis, outgrowth of neurites, microtubule dynamics, formation of cellular protrusions, and long‐term potentiation during NSC differentiation. On the other hand, PDL inhibited neuritogenesis, microtubule dynamics, and proliferation and differentiation of cells and activated the apoptosis function. Moreover, the nanomaterial promoted the expression of more let‐7 miRNAs, which have vital roles in NSC differentiation. Overall, SNF‐AP is biocompatible and applicable scaffold for NSC differentiation in the development of neural tissue engineering. These findings are useful in enhancingin vitroNSC differentiation potential for preclinical studies and future clinical applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2730–2743, 2016.
Biomechanics drive histological wall remodeling of neoaortic root: A mathematical model to study the expression levels of ki 67, metalloprotease, and apoptosis transition
Authors: Nappi Francesco , Fraldi Massimiliano , Spadaccio Cristiano , Carotenuto Angelo Rosario , Montagnani Stefania , Castaldo Clotilde , Chachques Juan Carlos , Acar Christophe
Published: June 2016

The pulmonary artery autograft (PA) is the ideal substitute for aortic valve disease in children and young adult. However, it is harnessed by the issue of long‐term dilation and regurgitation, often requiring surgery. PA implanted in aortic position during the growth phase in children undergoes a process of mechanical remodeling. We previously developed a semiresorbable armored prosthesis able to mechanically sustain the neoaorta preventing dilation and to gradually integrate with the PA wall inducing a progressive arterial‐like tissue positive remodeling. We also described the mechanisms of growth, remodeling and stress shielding of the reinforced PA through a mathematical model. We sought to demonstrate the biological counterpart and the potential molecular mechanisms underlying this histological and mechanical remodeling. A specific mathematical model was developed to describe mechanical behavior of the PA. Mallory trichrome red staining and immunohistochemistry for MMP‐9 were performed to elucidate extracellular matrix remodeling phenomena. Apoptosis and cell proliferation were determined by TUNEL assay and immunohistochemistry for Ki67, respectively. An histological remodeling phenomenon sustained by increased level of MMP‐9, augmented cell proliferation and reduced apoptosis in the reinforced PA was demonstrated. The mathematical model predicted the biomechanical behavior subtended by the histological changes of the PA in these settings. Changes in metalloproteinases (MMP‐9), cell proliferation and apoptosis are the main actors in the remodeling process occurring after transposition of the PA into systemic regimens. Use of semiresorbable reinforcements might induce a positive remodeling of the PA in the context of Ross operation. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2785–2793, 2016.
Serum miRNA Signatures Are Indicative of Skeletal Fractures in Postmenopausal Women With and Without Type 2 Diabetes and Influence Osteogenic and Adipogenic Differentiation of Adipose Tissue–Derived Mesenchymal Stem Cells In Vitro
Authors: Heilmeier Ursula , Hackl Matthias , Skalicky Susanna , Weilner Sylvia , Schroeder Fabian , Vierlinger Klemens , Patsch Janina M , Baum Thomas , Oberbauer Eleni , Lobach Iryna , Burghardt Andrew J , Schwartz Ann V , Grillari Johannes , Link Thomas M
Published: June 2016

Standard DXA measurements, including Fracture Risk Assessment Tool (FRAX) scores, have shown limitations in assessing fracture risk in Type 2 Diabetes (T2D), underscoring the need for novel biomarkers and suggesting that other pathomechanisms may drive diabetic bone fragility. MicroRNAs (miRNAs) are secreted into the circulation from cells of various tissues proportional to local disease severity and were recently found to be crucial to bone homeostasis and T2D. Here, we studied, if and which circulating miRNAs or combinations of miRNAs can discriminate best fracture status in a well-characterized study of diabetic bone disease and postmenopausal osteoporosis (n = 80 postmenopausal women). We then tested the most discriminative and most frequent miRNAs in vitro. Using miRNA-qPCR-arrays, we showed that 48 miRNAs can differentiate fracture status in T2D women and that several combinations of four miRNAs can discriminate diabetes-related fractures with high specificity and sensitivity (area under the receiver-operating characteristic curve values [AUCs], 0.92 to 0.96; 95% CI, 0.88 to 0.98). For the osteoporotic study arm, 23 miRNAs were fracture-indicative and potential combinations of four miRNAs showed AUCs from 0.97 to 1.00 (95% CI, 0.93 to 1.00). Because a role in bone homeostasis for those miRNAs that were most discriminative and most present among all miRNA combinations had not been described, we performed in vitro functional studies in human adipose tissue–derived mesenchymal stem cells to investigate the effect of miR-550a-5p, miR-188-3p, and miR-382-3p on osteogenesis, adipogenesis, and cell proliferation. We found that miR-382-3p significantly enhanced osteogenic differentiation (p < 0.001), whereas miR-550a-5p inhibited this process (p < 0.001). Both miRNAs, miR-382-3p and miR-550a-5p, impaired adipogenic differentiation, whereas miR-188-3p did not exert an effect on adipogenesis. None of the miRNAs affected significantly cell proliferation. Our data suggest for the first time that miRNAs are linked to fragility fractures in T2D postmenopausal women and should be further investigated for their diagnostic potential and their detailed function in diabetic bone. © 2016 American Society for Bone and Mineral Research.
Common Laboratory Parameters for Differentiating Between Community‐Acquired and Healthcare‐Associated Pneumonia
Authors: Farah Raymond , Bleier Jonathan , Gilbey Peter , Khamisy‐Farah Rola
Published: June 2016

Background and Objectives

The correct diagnosis of healthcare‐associated pneumonia (HCAP) as opposed to community‐acquired pneumonia is essential for the selection of a correct empirical antimicrobial approach, reserving the broad‐spectrum or highly potent antimicrobial therapies for resistant strains most commonly present in HCAP, whereas treating the less resistant strains, most commonly associated with community and long‐term care facility‐acquired infections, with a more targeted empirical approach. The standard approach today is to differentiate between the two based on the medical history of the past 90 days prior to admission. Measurable, quantitative assessment may be able to assist in this decision. The objective of this study is to find a measurable method of differentiating between community‐acquired and healthcare‐associated pneumonias.

Materials and Methods

The records of 126 patients admitted with a diagnosis of pneumonia were divided into two groups based on the probable cause of their disease, in accordance with common practice. The routine laboratory work taken upon admittance was analyzed using logistical regression and Student's t‐test.

Results

We have found that the red blood cell distribution width and the neutrophil‐to‐lymphocyte ratio, both routine parameters obtained in a simple blood count, can each assist in differentiating between community‐acquired and healthcare‐associated pneumonias.

Conclusion

We have found two statistically significant parameters that may be used as adjuncts to the medical history, chest radiography and other parameters in forming an immediate clinical impression of a patient presenting with pneumonia.
Combined Multidimensional Microscopy as a Histopathology Imaging Tool
Authors: Shami Gerald J. , Cheng Delfine , Braet Filip
Published: June 2016

Herein, we present a highly versatile bioimaging workflow for the multidimensional imaging of biological structures across vastly different length scales. Such an approach allows for the optimised preparation of samples in one go for consecutive X‐ray micro‐computed tomography, bright‐field light microscopy and backscattered scanning electron microscopy, thus, facilitating the disclosure of combined structural information ranging from the gross tissue or cellular level, down to the nanometre scale. In this current study, we characterize various aspects of the hepatic vasculature, ranging from such large vessels as branches of the hepatic portal vein and hepatic artery, down to the smallest sinusoidal capillaries. By employing high‐resolution backscattered scanning electron microscopy, we were able to further characterize the subcellular features of a range of hepatic sinusoidal cells including, liver sinusoidal endothelial cells, pit cells and Kupffer cells. Above all, we demonstrate the capabilities of a specimen manipulation workflow that can be applied and adapted to a plethora of functional and structural investigations and experimental models. Such an approach harnesses the fundamental advantages inherent to the various imaging modalities presented herein, and when combined, offers information not currently available by any single imaging platform. J. Cell. Physiol. 232: 249–256, 2017. © 2016 Wiley Periodicals, Inc.
Early development and differentiation of the Laysan albatross (Phoebastria immutabilis(Rothschild, 1893): Procellariiformes)
Authors: Rehorek Susan J. , Smith Timothy D. , Beeching Simon C.
Published: June 2016

Bird incubation is subdivided into two phases: differentiation (embryonic phase) and growth (fetal phase). Most birds have a relatively short incubation period (20–30 days) with the phase transition occurring midway through the incubation period. The Laysan albatross (Phoebastris immutabilis) is a large pelagic bird with a long incubation period. The purpose of this study was to document the differentiation phase with the aim of ascertaining the impact of a lengthened incubation on embryonic development. Eighty‐two previously collected albatross embryos were examined, measured, and staged. The albatross was found to develop more slowly than smaller birds, with a rate similar to other long‐incubating birds. Legs and wings grow at similar rates but exhibit variation in growth among their anatomical components. While the albatross embryos shared some morphological stages with chickens, they were more similar to ducks and pelicans. Special features of the albatross not shared with the Gallianserae (chickens and ducks) included an alligator‐like curved tail, narial tubes, and a cloacal bulge. Further examination of other larger pelagic birds with long incubation periods are needed to determine the uniqueness of the Laysan albatross embryonic development. Although much embryonic phase growth was documented in the postnatal period, little is known about the later, fetal phase in Laysan albatross. Future studies should involve examination of later (post day 32) fetuses. J. Morphol. 277:1231–1249, 2016. © 2016 Wiley Periodicals, Inc.
Optimization of o‐phtaldialdehyde/2‐mercaptoethanol postcolumn reaction for the hydrophilic interaction liquid chromatography determination of memantine utilizing a silica hydride stationary phase
Authors: Douša Michal , Pivoňková Veronika , Sýkora David
Published: June 2016

A rapid procedure for the determination of memantine based on hydrophilic interaction chromatography with fluorescence detection was developed. Fluorescence detection after postcolumn derivatization with o‐phtaldialdehyde/2‐mercaptoethanol was performed at excitation and emission wavelengths of 345 and 450 nm, respectively. The postcolumn reaction conditions such as reaction temperature, derivatization reagent flow rate, and reagents concentration were studied due to steric hindrance of amino group of memantine. The derivatization reaction was applied for the hydrophilic interaction liquid chromatography method which was based on Cogent Silica‐C stationary phase with a mobile phase consisting of a mixture of 10 mmol/L citric acid and 10 mmol/L o‐phosphoric acid (pH 6.0) with acetonitrile using an isocratic composition of 2:8 v/v. The benefit of the reported approach consists in a simple sample pretreatment and a quick and sensitive hydrophilic interaction chromatography method. The developed method was validated in terms of linearity, accuracy, precision, and selectivity according to the International Conference on Harmonisation guidelines. The developed method was successfully applied for the analysis of commercial memantine tablets.
Singing voice outcomes following singing voice therapy
Authors: Dastolfo‐Hromack Christina , Thomas Tracey L. , Rosen Clark A. , Gartner‐Schmidt Jackie
Published: June 2016

Objectives/Hypothesis

The objectives of this study were to describe singing voice therapy (SVT), describe referred patient characteristics, and document the outcomes of SVT.

Study Design

Retrospective.

Methods

Records of patients receiving SVT between June 2008 and June 2013 were reviewed (n = 51). All diagnoses were included. Demographic information, number of SVT sessions, and symptom severity were retrieved from the medical record. Symptom severity was measured via the 10‐item Singing Voice Handicap Index (SVHI‐10). Treatment outcome was analyzed by diagnosis, history of previous training, and SVHI‐10.

Results

SVHI‐10 scores decreased following SVT (mean change = 11, 40% decrease) (P < .001). Approximately 18% (n = 9) of patient SVHI‐10 scores decreased to normal range. The average number of sessions attended was three (± 2); patients who concurrently attended singing lessons (n = 10) also completed an average of three SVT sessions. Primary muscle tension dysphonia (MTD1) and benign vocal fold lesion (lesion) were the most common diagnoses. Most patients (60%) had previous vocal training. SVHI‐10 decrease was not significantly different between MTD and lesion.

Conclusions

This is the first outcome‐based study of SVT in a disordered population. Diagnosis of MTD or lesion did not influence treatment outcomes. Duration of SVT was short (approximately three sessions). Voice care providers are encouraged to partner with a singing voice therapist to provide optimal care for the singing voice. This study supports the use of SVT as a tool for the treatment of singing voice disorders.

Level of Evidence

4 Laryngoscope, 126:2546–2551, 2016
Nerve monitoring–guided selective hypoglossal nerve stimulation in obstructive sleep apnea patients
Authors: Heiser Clemens , Hofauer Benedikt , Lozier Luke , Woodson B. Tucker , Stark Thomas
Published: June 2016

Objective/Hypothesis

Selective stimulation of the upper airway is a new therapy for obstructive sleep apnea. The aim of the study was to determine if a selective nerve integrity monitoring (NIM) system could aid in precise placement of the cuff electrode in selective upper‐airway stimulation.

Study Design

Single‐center, prospective clinical trial.

Methods

Twenty patients who received a selective upper‐airway stimulation system (Inspire Medical Systems, Maple Grove, MN) were implanted by using a NIM system. The tongue motions were recorded during surgery and 2 months postoperatively from the transoral view and by transnasal endoscopy.

Results

All patients exhibited consistent protrusion at tongue front and tongue base. The nerve monitoring system helped to place the cuff electrode around the protrusion and stiffening branches, while excluding the retractor branches of the hypoglossal nerve.

Conclusion

This report demonstrated a novel use of a NIM system to identify the functional separation between inclusion and exclusion branches of the hypoglossal nerve for implantation of a selective upper‐airway stimulation system.

Level of Evidence

4. Laryngoscope, 126:2852–2858, 2016
Cochlear implantation via round window or cochleostomy: Effect on hearing in an animal model
Authors: Hod Roy , Attias Joseph , Raveh Eyal , Nageris Ben I.
Published: June 2016

Objectives/Hypothesis

Cochlear implantation in patients with residual hearing has increased interest in hearing preservation. Two major surgical approaches to implantation have been devised: via the round window membrane and through cochleostomy. However, the advantages of either approach on hearing preservation have not been established. Due to the great inter‐ and intravariability among implantees, the current study used a normal‐hearing animal model to compare the effect of the two methods on hearing.

Study Design

Animal study.

Methods

Thirteen fat sand rats were studied, in which 13 ears were implanted through cochleostomy and 13 via the round window. Hearing thresholds were determined by auditory brainstem responses to air and bone conduction at low and high auditory stimuli.

Results

The results indicated that each stage of the surgery, primarily the opening of the membranous labyrinth, was accompanied by significant deterioration in hearing. Hearing loss was mainly conductive, with no significant differences between the surgical approaches.

Conclusions

Both surgical approaches carry similar risk of hearing loss.

Level of Evidence

NA Laryngoscope, 126:E375–E378, 2016
Long‐term antibiofilm activity of carboxymethyl chitosan on mixed biofilm on silicone
Authors: Tan Yulong , Leonhard Matthias , Moser Doris , Ma Su , Schneider‐Stickler Berit
Published: June 2016

Objectives/Hypothesis

Silicone voice prostheses are most frequently used in voice rehabilitation of laryngectomized patients. However, the functional device lifetimes are limited due to formation of mixed biofilms. Existing in vitro models simulating biofilm formation are restricted to only short‐term periods.

Study Design

The goal of this study was to determine the effect of carboxymethyl chitosan on mixed biofilm formation of fungi and bacteria on silicone over a long‐term period.

Methods

Mixed species biofilms of Candida albicans, Candida tropicalis, Lactobacillus gasseri, Streptococcus salivarius, Rothia dentocariosa, and Staphylococcus epidermidis were cultivated on the surfaces of medical‐grade silicone with and without addition of carboxymethyl chitosan. Biofilm kinetics was monitored using specially designed image analysis software to calculate the percentual surface covering of each platelet. Biofilm architecture was investigated by scanning electron microscopy.

Results

A cover of living mixed biofilm could be generated over 22 days on silicone and the maximum of 22% biofilm surface covering at day 22. However, less than 4% surface coverage was observed on the carboxymethyl chitosan‐treated plates in the testing period. Scanning electron microscopy confirms that, on surfaces treated by carboxymethyl chitosan, the biofilm was less dense. In addition, there were fewer layers of cells and profuse cellular debris, together with degrading and morphologically altered yeast cells.

Conclusion

Carboxymethyl chitosan may serve as a possible antibiofilm agent to limit biofilm formation on voice prostheses.

Level of Evidence

NA Laryngoscope, 126:E404–E408, 2016
IsoCaRB: A novel bioreactor system to characterize the lability and natural carbon isotopic (14C, 13C) signatures of microbially respired organic matter
Authors: Beaupré Steven R. , Mahmoudi Nagissa , Pearson Ann
Published: June 2016

Organic matter is the dominant pool of reduced carbon in marine and freshwater systems. Mineralization of organic matter is largely attributed to complex and diverse microbial communities that mediate degradation and ultimately yield the terminal respiratory product, carbon dioxide (CO2). The factors that constrain the lability and degradation of organic matter remain unclear, but they involve a complex interplay between structural and chemical properties of the compounds, physical properties of the matrices, and the functional potential of the microorganisms that are present. To investigate these relationships, we developed a novel bioreactor system—called Isotopic Carbon Respirometer‐Bioreactor (IsoCaRB)—that permits real‐time monitoring of microbial CO2 production rates and collects sequential samples of this CO2 for off‐line isotopic analyses (13C, 14C). Application of this system to organic‐rich sediments from Salt Pond, MA reveals that organic matter is oxidized both abiotically and microbially, and that the pattern of microbial respiration by the native sediment community is complex, accessing different carbon substrates over the course of incubation. Isotopic measurements show modern organic matter of progressively older ages (≤ ca. 50 yr) is consumed, and this material has variable origins (salt marsh grasses, terrestrial, and marine organic matter). Collectively, the IsoCaRB system provides coupled insights into the sources, ages, and inherent biological and abiotic reactivity of natural organic matter.
Lower rates of receiving model for end‐stage liver disease exception and longer time to transplant among nonalcoholic steatohepatitis hepatocellular carcinoma
Authors: Young Kellie , Aguilar Maria , Gish Robert , Younossi Zobair , Saab Sammy , Bhuket Taft , Liu Benny , Ahmed Aijaz , Wong Robert J.
Published: June 2016

Receiving Model for End‐Stage Liver Disease (MELD) exception status for hepatocellular carcinoma (HCC) improves wait‐list survival and probability of liver transplantation (LT). We aim to evaluate etiology‐specific disparities in MELD exception, LT wait‐list times, and post‐LT outcomes among patients with HCC listed for LT. Using United Network for Organ Sharing 2004‐2013 data, we evaluated adults (age > 18 years) with HCC secondary to hepatitis C virus (HCV), nonalcoholic steatohepatitis (NASH), alcoholic cirrhosis (EtOH), hepatitis B virus (HBV), combined EtOH/HCV, and combined HBV/HCV. Multivariate regression models evaluated etiology‐specific odds of active exception, probability of receiving LT, and post‐LT survival. In total, 10,887 HCC patients were listed for LT from 2004 to 2013. Compared with HCV‐HCC patients (86.8%), patients with NASH‐HCC (67.7%), and EtOH‐HCC (64.4%) had a lower proportion with active MELD exception (P < 0.001). On multivariate regression, NASH‐HCC and EtOH‐HCC patients had significantly lower odds of active MELD exception compared with HCV‐HCC (NASH‐HCC—odds ratio [OR], 0.73; 95% confidence interval [CI], 0.58‐0.93; P = 0.01; EtOH‐HCC—OR, 0.72; 95% CI, 0.59‐0.89; P = 0.002). Compared with HCV‐HCC patients, NASH‐HCC (HR, 0.83; 95% CI 0.76‐0.90; P < 0.001), EtOH‐HCC (HR, 0.88; 95% CI 0.81‐0.96; P = 0.002), and EtOH/HCV‐HCC (HR, 0.92; 95% CI 0.85‐0.99; P = 0.03) were less likely to receive LT if they had active exception. Without active exception, these discrepancies were more significant (NASH‐HCC—HR, 0.22; 95% CI, 0.18‐0.27; P < 0.001; EtOH‐HCC—HR, 0.22; 95% CI, 0.18‐0.26; P < 0.001; EtOH/HCV‐HCC—HR, 0.26; 95% CI, 0.22‐0.32; P < 0.001). In conclusion, among US adults with HCC listed for LT, patients with NASH‐HCC, EtOH‐HCC, and EtOH/HCV‐HCC were significantly less likely to have active MELD exception compared with HCV‐HCC, and those without active exception had a lower likelihood of receiving LT. More research is needed to explore why NASH‐HCC patients were less likely to have active MELD exception. Liver Transplantation 22 1356–1366 2016 AASLD.
Biodegradable Multiblock Polymers Based on N‐(2‐Hydroxypropyl)methacrylamide Designed as Drug Carriers for Tumor‐Targeted Delivery
Authors: Mužíková Gabriela , Pola Robert , Laga Richard , Pechar Michal
Published: June 2016

Biodegradable multiblock (co)polymers based on N‐(2‐hydroxypropyl)methacrylamide (HPMA) for drug delivery applications are prepared by azide–alkyne polycycloaddition of end‐functionalized precursors synthesized by reversible addition–fragmentation chain transfer polymerization. Copper‐catalyzed polyaddition of the heterotelechelic polymer precursors containing azide and alkyne groups provides (A)x‐type multiblock (co)polymers. For the first time, thermally degradable multiblock polymers of (AB)x‐type are prepared via polyaddition of homotelechelic polymer diazides with azo‐compounds containing two alkyne groups. A novel type of HPMA‐based multiblock (co)polymers undergoing the pH‐dependent hydrolysis is reported. The (co)polymers containing the Asp‐Pro‐Lys sequence are relatively stable in an aqueous buffer at physiological pH 7.4; however, they undergo rapid hydrolysis at pH 5.0 corresponding to the pH in lysosomes. The multiblock polymer containing the Gly‐Phe‐Leu‐Lys linkage is degraded in the presence of the lysosomal protease cathepsin B. Thermal degradation of the (AB)x‐type multiblock polymers proceeds even at 37 °C, yielding a mixture of polymer degradation products with molecular weights below the renal threshold.

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Formation of Well‐Defined Polymer Particles in the Sub‐100 nm Size Range by Using Amphiphilic Block Copolymer Surfactants and a Microemulsion Approach
Authors: Kampmann Anne‐Larissa , Luksin Michael , Pretzer Irene , Weberskirch Ralf
Published: June 2016

Here, the formation of nanoparticles based on a microemulsion approach and the use of polymer surfactants are described. Therefore, two amphiphilic poly(2‐oxazoline) block copolymers P1 and P2 with alkyne groups in their hydrophobic block have been synthesized by ring‐opening, cationic polymerization. The polymers P1 and P2 are employed in a microemulsion process to stabilize the particle core by core cross‐linking of 1,6‐hexanediol diacrylate (HDDA) using either AIBN as azo‐initiator or 2‐propanethiol as a photo‐initiator for the polymerization reaction. The results show that particle size can be controlled by sonication time, the hydrophilic–hydrophobic balance of the polymer surfactant, and the ratio of polymer surfactant versus HDDA giving access to water‐soluble nanoparticles in a size range of 10–70 nm.

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Amino‐Acid‐Based Polymerizable Surfactants for the Synthesis of Chiral Nanoparticles
Authors: Preiss Laura C. , Wagner Manfred , Mastai Yitzhak , Landfester Katharina , Muñoz‐Espí Rafael
Published: June 2016

Amino‐acid‐based chiral surfactants with polymerizable moieties are synthesized, and a versatile approach to prepare particles thereof with a chiral surface functionality is presented. As an example of an application, the synthesized particles are tested for their ability as nucleating agents in the enantioselective crystallization of amino acid conglomerate systems, taking rac‐asparagine as a model system. Particles resulting from chiral surfactants with different tail groups are compared and the results demonstrate that only the chiral nanoparticles made of the polymerizable surfactant are able to act efficiently as nucleation agent in enantioselective crystallization.

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Stacked‐dielectric resonator antenna for TV white space application
Authors: Khan Rizwan , Kazim Jalil Ur Rehman , Ahmad Khan Aftab , Aqeel Sajid , Jamaluddin Mohd H. , Owais Owais , Khalid Usman
Published: June 2016

This article presents the design and measurement of a stacked‐dielectric resonator antenna for TV White Spaces. The antenna covers the range from 698 MHz to 810 MHz with reference to |S11| < −10 dB. It is composed of two DRAs of different dielectric materials which are stacked together and is excited by a coaxial probe. The volume is reduced by introducing a conducting wall on one side of DRA. Ground plane ensures that most of the power radiates to upper hemisphere. The measured and simulated results show good agreement. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2075–2079, 2016
Characterization of novel open notched quasi‐square metallic ring FSS using WCIP method for multiband applications
Authors: Adoui Ibtissem , Titaouine Mohammed , Choutri Hassina , Djouimaa Awatef , De Sousa Thayuan Rolim , Neto Alfredo G. , Baudrand Henri
Published: June 2016

A novel notched quasi‐square open metallic ring frequency selective surfaces (FSS) with single layer for triband applications is proposed. By the use of the wave concept iterative process (WCIP), the resonant characteristics of the proposed FSS are determined. The presented FSS shows three resonant frequencies when the incident wave is x‐polarized and one resonant frequency when the source is polarized in the orthogonal direction. A variation in the notched quasi‐square metallic ring dimensions allows a fine tuning in the FSS resonant frequencies to give raise to a tuned and enhanced bandwidth. Four FSS structures are manufactured and characterized. A good agreement is obtained when the WCIP results are compared with the simulations of COMSOL Multiphysics software and experiment. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2071–2075, 2016
Synthesis of a miniaturized dual‐band 3‐DB hybrid coupler through a general three‐step optimization process
Authors: Gong Jian‐Qiang , Huang Qi‐Man , Gao Kai
Published: June 2016

Synthesis method for a novel dual‐band hybrid coupler (DBHC) is presented in this letter. The proposed DBHC is built up using a novel dual‐band impedance transformer (DBIT). The DBIT is made up of a single kernel circuit unit cell with uniform transmission lines attached to its two ends. A system of nonlinear equations dominating the DBIT performance is first established and then successfully solved with numerical method. Design charts are provided for determining the feasible DBIT parameters. With the DBIT theoretical solutions, a microstrip DBHC centered at 2.4/5.8 GHz is practically implemented, of which layout parameters are effectively resolved through a sequential three‐step optimization design process, and its compact size as well as good dual‐band operational performance has been demonstrated by fabrication and measurement, validating the proposed synthesis method. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2057–2062, 2016
Investigation on the performance of low‐profile insensitive antenna with improved radiation characteristics for the future 5G applications
Authors: Ojaroudiparchin N. , Shen M. , Pedersen G. F.
Published: June 2016

A new method to design an insensitive antenna with improved performance for fifth generation (5G) systems is proposed in this letter. In order to improve the antenna performance and also eliminate the effect of high‐loss FR‐4 substrate, the resonator of the conventional slot antenna has been converted to the air‐filled slot‐loop structure with a thickness of hsub. Since the main substrate of the resonator is the air, the antenna is insensitive for different values of permittivity, loss tangent characteristics of the substrate. So, for different kinds of substrates, the antenna has a same performance in terms of maximum gain, radiation and total efficiencies. The antenna is designed and fabricated on a low‐cost FR4 substrate and has more than 90% (−0.5 dB) radiation and total efficiencies at 22.25 GHz (center frequency). It has the reflection coefficient (S11) less than −10 dB in the frequency range of 21–23.5 GHz (more than11% fractional bandwidth) which is one of the candidate bands for future 5G communications. The antenna has a very compact size and could be used in mm‐wave phased arrays. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2148–2151, 2016
Characterization of high‐photocurrent and high‐speed INP‐based uni‐traveling‐carrier photodiodes at 1.55‐μm wavelength
Authors: Meng Qianqian , Wang Hong , Liu Chongyang , Gao Jianjun , Tian Yang , Siong Ang Kian , Guo Xin , Gao Bo
Published: June 2016

We demonstrate a semi‐analytical parameter extraction method to characterize high‐speed and high‐photocurrent InP‐based uni‐traveling‐carrier photodiodes with dipole‐doped structure. The accuracy of proposed method has been validated with good agreements between the measured and simulated results of reflection coefficients and frequency responses in a wide frequency range up to 40 GHz. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2156–2162, 2016
Experimental validation of a wireless system for the irrigation management in smart farming applications
Authors: Viani Federico
Published: June 2016

This work is aimed at presenting the water saving potentialities of a scalable smart irrigation system applied to precision agriculture. A fuzzy logic strategy is integrated in a distributed monitoring system based on the wireless sensor network technology. The optimal irrigation schedule is adaptively estimated according to the real‐time measurement of the soil status and the weather conditions. The objective of the system is to optimize the water content in the soil to (i) maximize the health status of the plants, (ii) improve the quality of the products, and (iii) reduce the waste of water. The proposed system has been prototyped and experimentally validated in an apple orchard, close to the city of Trento, in the north of Italy. The performances of the proposed system are compared with those of a standard irrigation scheduler to point out the amount of saved water as well as the improved stability of the soil moisture level. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2186–2189, 2016
Antenna miniaturization using pulp fibres as a substrate for dual band operation
Authors: Khan Asim Ali , Razaq Aamir , Ali Jawad , Arshad Faisal , Mumtaz Musaiyab , Khan Sajid
Published: June 2016

Reduced size dual band patch antenna is designed on pulp fibers‐based substrate, obtained from a self‐growing plant, Typha angustifolia. The proposed design is low cost and has <10 dB return loss at 2.4 and 5.7 GHz, with 6.9 dBi antenna gain and also has potential for conformal designs. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2146–2148, 2016
A design of UWB reconfigurable pulse transmitter with pulse shape modulation
Authors: Valizade A. , Rezaei P. , Orouji A. A.
Published: June 2016

A new design of ultra‐wideband (UWB) reconfigurable pulse transmitter (PT) based on active integrated antenna (AIA) structure is introduced in this article. The presented reconfigurable AIA consists of a reconfigurable sub‐nanosecond pulse generator (PG) which is integrated with a monopole circular disk antenna. The proposed design utilizes only a single step‐recovery diode (SRD) and just a single positive‐intrinsic‐negative (PIN) diode in order to generate sub‐nanosecond switchable second/third order derivatives of Gaussian pulse. The performance of the designed PT system is investigated in both frequency domain and time domain. Low ringing level, high signal fidelity, and virtually steady group delay is achieved in the frequency band of operation. The simplicity, low cost, and good performance of the presented PT makes it a good candidate for UWB transmission with pulse shape modulation (PSM). © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2221–2227, 2016
Miniaturized log periodic dipole array with complementary split‐ring resonators
Authors: Lu Xiuyuan , Yang Guo‐Min
Published: June 2016

This letter presents a study on antenna miniaturization and bandwidth enhancement of the log‐periodic dipole array (LPDA) with a novel structure of complementary split‐ring resonator (CSRR). The bandwidth of LPDA can be enhanced without enlarging its size, and the performance characteristics can be maintained. Characteristics including S parameter, directivity and gain are compared, and the advantages and application methodology of CSRRs are proposed. This design enhanced the bandwidth from 0.6‐1.8 GHz (3:1) to 0.4‐1.8GHz (4.5:1), or achieved a size reduction of up to 26.7%. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2217–2221, 2016
Design and fabrication of rectangular ring monopole array with parasitic elements for UWB applications
Authors: Ali Wael A. , Zaki Amira I. , Abdou Mahmoud H.
Published: June 2016

In this paper a low cost rectangular ring monopole antenna element and antenna array with parasitic patches are presented for ultra‐wideband applications. The proposed antenna element and antenna array are constructed with a modified partial ground plane on FR4 epoxy substrate with relative permittivity 4.4 and thickness 1.5 mm. A parametric study on the main parameters of the radiating elements and the distance between them as well as the partial ground has been investigated to optimize the design of the antenna array. The return loss is less than −10 dB in the frequency range 3.6–9.6 GHz which makes it suitable for UWB applications. Impedance and radiation characteristics of the proposed antenna are simulated using Ansoft HFSS 13 software. The simulated and measured results show good agreement and validate the proposed approach. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2268–2273, 2016
Investigation of surface wave propagation along a multi‐coil wireless power transfer system
Authors: Xu Bin , Li Yang
Published: June 2016

The surface wave propagation along a multi‐coil wireless power transfer system is investigated with the motivation of extending power transfer range. First, the power transfer efficiencies of coil arrays with different numbers of repeaters are simulated and measured. Then the wave propagation along the array is investigated and its associated wave characteristics are extracted using a super resolution algorithm. A backward traveling surface wave is found to be the dominant propagation mechanism, and its decay constant decreases as the number of repeater increases. An empirical formula correlating the power transfer efficiency with the surface wave decay constant is proposed. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2261–2265, 2016
Advantages and limitations of 3D printing a dual‐ridged horn antenna
Authors: Majumdar Budhaditya , Baer David , Chakraborty Sudipta , Esselle Karu P. , Heimlich Michael
Published: June 2016

Conventional and additive manufacturing (three‐dimensional [3D] printing) techniques for a dual‐ridged horn antenna (DRHA) are presented. The different aspects of the conventional manufacturing of a DRHA and the limitations incurred during additive manufacturing are discussed in detail. The antenna design was further optimized for fused deposition modeling and was 3D printed using acrylonitrile butadiene styrene (ABS). The polymer‐based print was painted with nickel‐based aerosol spray. The coaxial transition is also included in the 3D printed prototype. The antenna was manufactured with the intention of improving the learning and education of electromagnetism and antennas of undergraduate students using a low‐cost personal desktop 3D printer. The painted DRHA has a 10 dB return‐loss bandwidth of 6621 MHz (1905–8526 MHz) with a peak gain of 11 dBi. The average cross‐polarization isolation achieved was more than 25 dB. Rapid prototyping was possible with additive manufacturing, and limitations were addressed with conventional machining processes whenever required. This prototype is the first known ABS‐based horn antenna with the coaxial transition embedded into it. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2110–2117, 2016