bluuebunny/crossref_metadata_2025_split huggingface dataset:
Longitudinal Changes in BMD and Fracture Risk in Orthotopic Liver Transplant Recipients Not Using Bone-Modifying Treatment
Authors: Krol Charlotte G , Dekkers Olaf M , Kroon Herman M , Rabelink Ton J , van Hoek Bart , Hamdy Neveen AT 
Published: March 2014

ABSTRACT

Osteoporosis is prevalent in end-stage liver disease, but data on long-term changes in bone mineral density (BMD) and related fracture incidence after orthotopic liver transplantation (OLT) are scarce. We evaluated BMD changes up to 5 years in consecutive recipients of a successful OLT at the Leiden University Medical Centre between 2000 and 2011, in whom sequential BMD data were available. Spinal radiographs were available at time of screening and at 6 and 12 months post-OLT and were assessed for vertebral fractures by two independent observers using Genant's semiquantitative method. Patients were excluded from the study when started on bisphosphonates. A total of 201 patients (71% men), median age 53 years (range, 18–70 years) were included in the study. Most common liver pathology was viral (27%) or alcoholic liver disease (25%). All patients received prednisone for at least 6 months after transplantation and the majority received either tacrolimus or cyclosporine for immunosuppression. At time of screening for OLT, osteoporosis and osteopenia were found in 18% and 36% of patients at the lumbar spine (LS), respectively, and in 9% and 42% at the femoral neck (FN), respectively. T-scores declined significantly at both sites 6 months after OLT, but increased thereafter at the LS, reaching pretransplantation values at 2 years and remaining stable thereafter. FN T-scores remained consistently lower than pretransplantation values. The prevalence of vertebral fractures increased from 56% at screening to 71% at 1 year after OLT, with a fracture incidence of 34%. BMD changes did not predict fracture risk. Osteoporosis, osteopenia, and vertebral fractures are prevalent in patients with end-stage liver disease. An overall decline in BMD is observed within the first 6 months after OLT, with subsequent recovery to pretransplantation values at the LS, but not at the FN. Vertebral fracture risk is high after OLT regardless of changes in BMD. © 2014 American Society for Bone and Mineral Research.
Heat stress induced cell death mechanisms in hepatocytes and hepatocellular carcinoma: In vitro and in vivo study
Authors: Thompson Scott M. , Callstrom Matthew R. , Butters Kim A. , Knudsen Bruce , Grande Joseph P. , Roberts Lewis R. , Woodrum David A. 
Published: March 2014

ABSTRACTBackground and ObjectiveThe aims of the present study were to investigate the thermal‐dose dependent effect of heat stress on hepatocyte and HCC cell death mechanisms using clinically relevant experimental heat stress conditions in vitro and to investigate apoptotic cell death induced by laser thermal ablation in vivo.Study Design/Materials and MethodsInstitutional Animal Care and Use Committee approved all studies. Hepatocyte and HCC cell lines were heat stressed from 37 to 60°C for 2 or 10 minutes and assessed for viability, cytotoxicity and caspase‐3/7 activity at 6 and/or 24 hours post‐treatment (N = 3). Viability experiments were repeated with the RIPK1 inhibitor Necrostatin‐1 to block necroptosis (N = 3). Rats with orthotopic HCC tumors stably expressing luciferase (N1S1luc2) were randomized to US‐guided laser ablation (3W‐45s for an intentional partial ablation; N = 6) or sham (N = 6) and followed by post‐ablation caspase‐3/7 bioluminescence imaging at 6 and 24 hours and cleaved caspase‐3 immunostaining. P < 0.05 was considered statistically significant.ResultsHeat‐stress induced apoptosis and necrosis in hepatocytes and HCC cells in a thermal dose and cell‐type dependent manner. Inhibition of RIPIK1‐mediated necroptosis induced a significant, differential increase in HCC cell viability under physiologic and hyperthermic heat stress (P < 0.001). Intentional partial laser thermal ablation induced a significant increase in caspase‐3/7 activity in the laser versus sham ablation groups at both 6 hours (10.1‐fold, P < 0.01) and 24 hours (16.7‐fold, P < 0.02). Immunohistochemistry confirmed increased cleaved caspase‐3 staining at the tumor ablation margin 24 hours post‐ablation.ConclusionsBoth regulated and non‐regulated cell death mechanisms mediate heat stress‐induced HCC cell killing and vary between hepatocytes and HCC subtypes. Apoptosis is a significant mechanism of cell death at the HCC tumor ablation margin. Lasers Surg. Med. 46:290–301, 2014. © 2014 Wiley Periodicals, Inc.
LECTINPred: web Server that Uses Complex Networks of Protein Structure for Prediction of Lectins with Potential Use as Cancer Biomarkers or in Parasite Vaccine Design
Authors: Munteanu Cristian R. , Pedreira Nieves , Dorado Julián , Pazos Alejandro , Pérez‐Montoto Lázaro G. , Ubeira Florencio M. , González‐Díaz Humberto 
Published: March 2014

AbstractLectins (Ls) play an important role in many diseases such as different types of cancer, parasitic infections and other diseases. Interestingly, the Protein Data Bank (PDB) contains +3000 protein 3D structures with unknown function. Thus, we can in principle, discover new Ls mining non‐annotated structures from PDB or other sources. However, there are no general models to predict new biologically relevant Ls based on 3D chemical structures. We used the MARCH‐INSIDE software to calculate the Markov‐Shannon 3D electrostatic entropy parameters for the complex networks of protein structure of 2200 different protein 3D structures, including 1200 Ls. We have performed a Linear Discriminant Analysis (LDA) using these parameters as inputs in order to seek a new Quantitative Structure‐Activity Relationship (QSAR) model, which is able to discriminate 3D structure of Ls from other proteins. We implemented this predictor in the web server named LECTINPred, freely available at http://bio‐aims.udc.es/LECTINPred.php. This web server showed the following goodness‐of‐fit statistics: Sensitivity=96.7 % (for Ls), Specificity=87.6 % (non‐active proteins), and Accuracy=92.5 % (for all proteins), considering altogether both the training and external prediction series. In mode 2, users can carry out an automatic retrieval of protein structures from PDB. We illustrated the use of this server, in operation mode 1, performing a data mining of PDB. We predicted Ls scores for +2000 proteins with unknown function and selected the top‐scored ones as possible lectins. In operation mode 2, LECTINPred can also upload 3D structural models generated with structure‐prediction tools like LOMETS or PHYRE2. The new Ls are expected to be of relevance as cancer biomarkers or useful in parasite vaccine design.
A new microstrip patch antenna with triple‐polarization diversity
Authors: Dasari Rama Krishna , Pandharipande V. M. , Koul Shiban K. 
Published: March 2014

ABSTRACTIn recent years, polarization agility in single antenna is most desired characteristic in different applications. In this article, a microstrip antenna with new triple‐polarization diversity is designed and developed for C‐band pulsed altimeter used in many of the missile/aerospace application. The achieved polarization includes elliptical polarization, circular polarization (CP), and linear polarization. The antenna can be biased to get either right‐handed circular polarization (RHCP) or left‐handed circular polarization (LHCP). The antenna consists of a rectangular patch, four PIN diodes and two feeding lines along vertical and horizontal edge of the antenna. The necessary biasing network also embedded in the antenna circuit. Four PIN diodes are used for the polarization diversification and controlled by +5V external DC power supply. A prototype of the antenna has been fabricated and tested. Simulated results are in agreement with experimental data. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1348–1353, 2014
Novel dual‐band dual‐prototype bandpass filter
Authors: Sun Xiaofeng , Tan Eng Leong 
Published: March 2014

ABSTRACTThis article presents the novel dual‐band dual‐prototype bandpass filter. The corresponding lowpass prototypes of the first and second passbands of the proposed filter are controllable and can be specified to be different at the outset. The dual‐band resonator is realized by trisection stepped‐impedance resonator. The dual‐band inverter is implemented by stepped‐impedance admittance inverter which can satisfy two different admittance values to realize two different frequency responses at two passbands. To compare and make more obvious the two passbands with two different lowpass prototypes, the proposed filter is illustrated with the
lowpass prototype for its first band and the
lowpass prototype for its second band. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1496–1498, 2014
Air‐gapped microcoxial transmission line for ultrawide band microwave and millimeter wave ICS
Authors: Tian Yang , Lee Kokyan , Wang Hong 
Published: March 2014

AbstractWe present an air‐gapped microcoaxial transmission line fabricated on low resistivity silicon substrate (ρ = 10 Ω·cm). The transmission line is based on a damascene copper process and has demonstrated superior microwave properties of low attenuation (<0.02 dB/mm) and a low and constant effective permittivity (∼1.02) in the frequency range of 0.1–40 GHz. The fabrication process has a low thermal budget, and can be easily integrated with the advanced Cu back‐end‐of‐line CMOS to fabricate low‐loss and high quality factor microwave and millimeter wave passives for system‐on‐chip applications. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1462–1465, 2014
A novel single feed of circular polarized antenna and open area test site measurements for 2.4 GHz application
Authors: Nayan M. K. A. , Jamlos M. F. , Jusoh M. , Jamlos M. A. , Sabapathy T. , Jais M. I. 
Published: March 2014

ABSTRACTA novel single feed of the truncated edge circular polarized array antenna for 2.4 GHz applications with high gain is analyzed and proposed. The presented circular polarized antenna is comprised of four patches as its radiating elements and fed by a single coaxial connector at the ground layer. Dimension‐wise, the proposed antenna is designed with compact size of 56 × 69 × 1.6 mm3. It is notified that 45° of patches' truncated edge, 45 mm element spacing of Y‐axis, and 39.5 mm element spacing of X‐axis collectively contribute to the circular polarization capability. The prototype of the antenna has a right‐hand circular polarization with an axial ratio of 2.019 in particular of 2.4 GHz. Additionally, the similarity patterns of E‐plane and H‐plane of the antenna prove its circular polarization capability. Further, the proposed antenna seems to have an omnidirectional pattern eventhough using a full ground plane and improved the effective coverage angle. With the measured gain of 5.35 dB and the reflection coefficient of −14.16 dB, the proposed antenna has big potential for Wi‐Fi and biomedical application. The antenna prototype performance is verified, and the experimental result is presented and discussed. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1337–1344, 2014
High‐selectivity wideband bandpass filter using quarter‐wave coupled lines and quarter‐wave series transformers
Authors: Wu Xiao‐Hu , Chu Qing‐Xin 
Published: March 2014

ABSTRACTWideband bandpass filter with high‐selectivity is presented in this article. An initial circuit model, which is composed of quarter‐wave coupled lines, is given and analyzed that sharp passband selectivity can be obtained by the two transmission zeros, which are generated by the short‐ended parallel‐coupled lines. Then, the quarter‐wave impedance transformers are added to improve the passband transmission and reflection characteristics. The filter is analyzed, designed, fabricated, and measured. Simulated and measured results are well‐agreed. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1418–1421, 2014
Two‐stage tunable passive fiber mode‐locked laser
Authors: Jang Ya Ru , Lin Wen Piao , Kuo Han Lung 
Published: March 2014

ABSTRACTIn this article, a broadband tunable Ytterbium‐doped fiber passive mode‐locked ring laser in 1060 nm utilizing bidirectional pumping structure is proposed. It has more stable pulse and higher repetition rate output than the constructive fiber ring laser. Moreover, this laser can provide more convenient to use in medical field. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1468–1470, 2014
A design of wideband circularly polarized antenna with high gain
Authors: Liu Neng‐Wu , Zhang Zhi‐Ya , Zhao Jia‐yue , Fu Guang , Yao Ya‐li 
Published: March 2014

ABSTRACTA wideband circularly polarized (CP) antenna with high gain is proposed. The circular polarization performance is obtained by two pairs of orthogonal bowtie dipoles with a coaxial balun feed and a broadband 90° hybrid feed network. Particularly, a design of rectangular ring with eight shorted posts is added around the bowtie dipoles, which can obtain a high gain. To further improve the gain of the novel antenna, a circular ring is placed around the rectangular ring on the same plane. With such an arrangement, the proposed antenna delivers a higher gain than that of the conventional dual‐fed type CP antenna. The measured results show that the proposed antenna can achieve a measured impedance bandwidth for VSWR ≤ 1.5 of 61.5% and a 3‐dB axial ratio bandwidth of 66.7%. The antenna has a stable peak CP gain better than 10.3 dBi ranging from 1.1 to 1.6 GHz. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1274–1277, 2014
Frequency scannable stacked patch antenna for beam‐steering applications
Authors: Liu Wen‐Chung , Lin Yu‐Fan , Wu Chao‐Ming 
Published: March 2014

ABSTRACTA single element wideband antenna that has a stacked structure and provides beam‐steering characteristic according to the operating frequency is presented. Without requirements of phase shifters and associated circuits, the proposed antenna is composed of a circular patch electromagnetically coupled by a meandered‐strip feeder and a slotted conducting plane to have a compact size. The beam direction of the designed antenna can be mainly controlled by the operating frequency with a large beam scanning angle. From fabricating and testing the antenna, an operating bandwidth of 2.3 GHz (3.8–6.1 GHz) and an average gain of about 3.8 dBi have been obtained, and in addition, the beam‐steering characteristic has also been verified. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1506–1509, 2014
Design of fully printed omnidirectional CRLH loop antennas for WLAN technology
Authors: Locatelli Andrea , Modotto Daniele , De Angelis Costantino , Boscolo Stefano , Midrio Michele , Capobianco Antonio D. 
Published: March 2014

ABSTRACTWe report numerical and experimental results concerning fully printed loop antennas for WLAN communications based on composite right‐/left‐handed transmission lines. In this work, we describe a different approach and methodology with respect to other omnidirectional loop antennas that have already been presented in the literature. Indeed, we exploit the possibility of using only printed elements for loading the loop, and we show that this solution offers new degrees of freedom for fine tuning of the operating frequency and for a deep optimization of the omnidirectional radiation pattern. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1405–1408, 2014
A four‐port 12‐beam phased array antenna system
Authors: Chang Ching‐Jen , Yen Lei , Datta Jayanta , Lin Hsin‐Piao , Jeng Shiann‐Shiun 
Published: March 2014

ABSTRACTIn this work, we propose a novel solution for a switched beamformer called the adjustable phased array system (APAS). By programming electronic switches, the implemented four‐antenna APAS circuit generates 12 phase‐shift angles that are multiples of
. Compared to the legacy
Butler matrix, the proposed APAS only needs one input port and four output ports and can provide more beam patterns with lower cost. Therefore, the APAS structure is a practical solution to satisfy the modern multiuser MIMO applications. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1375–1378, 2014
Numerical investigation of airborne radars for remote sensing applications
Authors: da Costa Igor F. , da Silva Luis G. , Mologni Juliano F. , Cerqueira S. Arismar 
Published: March 2014

ABSTRACTThis article reports an accurate numerical investigation of some technological solutions for embedded airborne radars in the P‐ and X‐bands applied to remote sensing. The propagation analyses are based on transient and Floquet simulations by taken into account the influence of an entire fuselage from a commercial plane and the vegetation electromagnetic characteristics, similar to Amazon rainforest, to reproduce a realistic situation. Moreover, it is designed and analyzed a log‐periodic antenna with dual polarization for embedded airborne radars. The antenna analysis is based on S‐parameters and radiation pattern characteristics. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1473–1478, 2014
New metamaterial structure with SRR in the shape of split equilateral triangles for application in microstrip antennas
Authors: Morais José H. C. , Silva Sandro 
Published: March 2014

ABSTRACTA new metamaterial structure was proposed. The model is an extension of the case circular SRR of Pendry. In the analysis of the structure were obtained characteristics of negative permeability different from the original model. A fractal modular composition with split triangles resonator was produced and simulations and prototypes of microstrip antennas were performed. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1397–1401, 2014
High‐sensitive temperature sensor based on an alcohol‐filled HiBi photonic crystal fiber loop mirror
Authors: Zhao Yong , Gao Peng 
Published: March 2014

ABSTRACTA temperature sensor based on a High‐Birefringence photonics crystal fiber loop mirror (HiBi‐PCF‐FLM) with a reflection probe was theoretical simulated and experimentally demonstrated. The interference spectrum of the FLM presented high sensitivity to temperature variation of the surrounding medium. High‐temperature sensitivity of 7.38 nm/°C with good linearity was obtained in theory; this result was proved by the consequent experiment. Meanwhile, the measuring range of temperature can be tuned using the HiBi‐PCF with different length or Birefringence. As the reflection probe is a reflected structure, it is benefit to use in the area of high‐sensitivity remote temperature sensing. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1334–1337, 2014
Opening and closing of a toroidal group II chaperonin revealed by a symmetry constrained elastic network model
Authors: Lee Hoomin , Seo SangJae , Kim Minhyeok , Choi Jae boong , Kim Sun Min , Jeon Tae‐Joon , Kim Moon Ki 
Published: March 2014

AbstractRecently, the atomic structures of both the closed and open forms of Group 2 chaperonin protein Mm‐cpn were revealed through crystallography and cryo‐electron microscopy. This toroidal‐like chaperonin is composed of two eightfold rings that face back‐to‐back. To gain a computational advantage, we used a symmetry constrained elastic network model (SCENM), which requires only a repeated subunit structure and its symmetric connectivity to neighboring subunits to simulate the entire system. In the case of chaperonin, only six subunits (i.e., three from each ring) were used out of the eight subunits comprising each ring. A smooth and symmetric pathway between the open and closed conformations was generated by elastic network interpolation (ENI). To support this result, we also performed a symmetry‐constrained normal mode analysis (NMA), which revealed the intrinsic vibration features of the given structures. The NMA and ENI results for the representative single subunit were duplicated according to the symmetry pattern to reconstruct the entire assembly. To test the feasibility of the symmetry model, its results were also compared with those obtained from the full model. This study allowed the folding mechanism of chaperonin Mm‐cpn to be elucidated by SCENM in a timely manner.
Understanding ancient Maya water resources and the implications for a more sustainable future
Authors: French Kirk D. , Duffy Christopher J. 
Published: March 2014

Archeological research often provides a glimpse into the daily lives and generational outcomes of our collective past, but rarely does it lead to significant effects on living (and possibly future) populations. Understanding the impact early civilizations had on their environment has been an active area of study since the 1950s. As one of the most vital resources, water is central to many of these scholarly endeavors. Research has shown that land use is a primary factor on the functionality of a watershed. Our hypothesis is that simulating past climate and hydrology of a watershed with probable land use scenarios can create a virtual experiment to explore a range of conditions for water availability and use in prehistoric landscapes. The ancient Maya lived in a varied environment with highly seasonal precipitation and landscapes that required vastly different water management strategies. Many of these ancient centers maintained dense populations that ultimately forced unsustainable land use practices. Our approach is to apply simulated climate projections to evaluate the hydrologic performance of watersheds surrounding the Classic Maya sites of Palenque, Mexico and Tikal, Guatemala. An important conclusion from our work at Palenque is that virtual data can provide a plausible framework for assessing the sustainability of water use strategies, past and present.This article is categorized under:

Engineering Water > Planning Water
Science of Water > Water and Environmental Change
Science of Water > Water Extremes