bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of proton irradiation on dc performance of AlGaN/GaN high electron mobility transistors
Authors: Liu Lu , Velez Cuervo Camilo , Xi Yuyin , Ren Fan , Pearton Stephen J. , Kim Hong-Yeol , Kim Jihyun , Kravchenko Ivan I.
Published: July 2013

The effects of high energy proton irradiation dose on dc performance as well as critical voltage of the drain-voltage step-stress of AlGaN/GaN high electron mobility transistors (HEMTs) were investigated to evaluate the feasibility of AlGaN/GaN HEMTs for space applications, which need to stand a variety of irradiations. The HEMTs were irradiated with protons at a fixed energy of 5 MeV and doses ranging from 109 to 2 × 1014 cm−2. For the dc characteristics, there was only minimal degradation of saturation drain current (IDSS), transconductance (gm), electron mobility, and sheet carrier concentration at doses below 2 × 1013 cm−2, while the reduction of these parameters were 15%, 9%, 41% and 16.6%, respectively, at a dose of 2 × 1014 cm−2. At this same dose condition, increases of 37% in drain breakdown voltage (VBR) and of 45% in critical voltage (Vcri) were observed. The improvements of drain breakdown voltage and critical voltage were attributed to the modification of the depletion region due to the introduction of a higher density of defects after irradiation at a higher dose.
CCAAT/Enhancer Binding Protein δ in Macrophages Contributes to Immunosuppression and Inhibits Phagocytosis in Nasopharyngeal Carcinoma
Authors: Hsiao Yu-Wei , Li Chien-Feng , Chi Jhih-Ying , Tseng Joseph T. , Chang Yao , Hsu Li-Jin , Lee Chien-Hsun , Chang Tsung-Hao , Wang Shao-Ming , Wang Dennis Ding Hwa , Cheng Hung-Chi , Wang Ju-Ming
Published: July 2013

The transcription factor C/EBPδ makes tumor-associated macrophages produce signals that aid the tumor.
Cancer Hits a Nerve
Authors: Kiberstis Paula A.
Published: July 2013

Prostate cancer is more aggressive when certain types of nerves form near and within the tumor.
Confining Hippo for Fate Specification
Authors: VanHook Annalisa M.
Published: July 2013

Polarized distribution of angiomotin restricts Hippo signaling to the inner cell mass in mouse blastocysts.
Rejecting the Wrong Mate
Authors: Gough Nancy R.
Published: July 2013

By touching potential mates, fruit fly males sense the hydrocarbon composition of the female’s cuticle to decide if she is of the right species.
Amphotericin B- and Voriconazole-Echinocandin Combinations against Aspergillus spp.: Effect of Serum on Inhibitory and Fungicidal Interactions
Authors: Elefanti Antigoni , Mouton Johan W. , Verweij Paul E. , Tsakris Athanassios , Zerva Loukia , Meletiadis Joseph
Published: July 2013

Antifungal combination therapy with voriconazole or amphotericin B and an echinocandin is often employed as primary or salvage therapy for management particularly of refractory aspergillosis. The pharmacodynamic interactions of amphotericin B- and voriconazole-based combinations with the three echinocandins caspofungin, micafungin, and anidulafungin in the presence of serum were tested against 15
Aspergillus fumigatus
complex,
A. flavus
complex, and
A. terreus
complex isolates to assess both their growth-inhibitory and fungicidal activities. The
in vitro
activity of each drug alone and in combination at a 1:1 fixed concentration ratio was tested with a broth microdilution colorimetric method, and interactions were assessed by isobolographic analysis. Synergy was found for all amphotericin B- and voriconazole-based combinations, with amphotericin B-based combinations showing strong inhibitory synergistic interactions (interaction indices of 0.20 to 0.52) and with voriconazole-based combinations demonstrating strong fungicidal synergistic interactions (interaction indices of 0.10 to 0.29) (
P
< 0.001). Drug- and species-specific differences were found, with caspofungin and the
A. fumigatus
complex exhibiting the weakest synergistic interactions. In the presence of serum, the synergistic interactions were reduced in the order (from largest to smallest decrease) micafungin > anidulafungin > caspofungin, and
A. flavus
complex >
A. fumigatus
complex >
A. terreus
complex, resulting in additive interactions, particularly for inhibitory activities of amphotericin B-echinocandin combinations and fungicidal activities of voriconazole-echinocandin combinations. Drug- and species-specific differences were found in the presence of serum for inhibitory activities of antifungal drugs, with the lowest interaction indices being observed for amphotericin B-caspofungin (median, 0.77) and for the
A. terreus
complex (median, 0.56). The present
in vitro
data showed that serum had a major impact on synergistic interactions of amphotericin B-echinocandin and voriconazole-echinocandin combinations, resulting in additive interactions and explaining the indifferent outcomes usually observed
in vivo
.
Cost-Effectiveness Analysis Comparing Two Approaches for Empirical Antifungal Therapy in Hematological Patients with Persistent Febrile Neutropenia
Authors: Martín-Peña Almudena , Gil-Navarro M. Victoria , Aguilar-Guisado Manuela , Espigado Ildefonso , de Pipaón Maite Ruiz Pérez , Falantes José , Pachón Jerónimo , Cisneros José M.
Published: July 2013

New approaches of empirical antifungal therapy (EAT) in selected hematological patients with persistent febrile neutropenia (PFN) have been proposed in recent years, but their cost-effectiveness has not been studied. The aim of this study was to compare the cost-effectiveness of two different approaches of EAT in hematological patients with PFN: the diagnosis-driven antifungal therapy (DDAT) approach versus the standard approach of EAT. A decision tree to assess the cost-effectiveness of both approaches was developed. Outcome probabilities and treatment pathways were extrapolated from two studies: a prospective cohort study following the DDAT approach and a randomized clinical trial following the standard approach. Uncertainty was undertaken through sensitivity analyses and Monte Carlo simulation. The average effectiveness and economic advantages in the DDAT approach compared to the standard approach were 2.6% and €5,879 (33%) per PFN episode, respectively. The DDAT was the dominant approach in the 99.5% of the simulations performed with average cost-effectiveness per PFN episode of €32,671 versus €52,479 in the EAT approach. The results were robust over a wide range of variables. The DDAT approach is more cost-effective than the EAT approach in the management of PFN in hematological patients.
Differential Adaptive Responses of Staphylococcus aureus to
In Vitro
Selection with Different Antimicrobial Peptides
Authors: Shireen Tahsina , Singh Madhuri , Das Tiyasa , Mukhopadhyay Kasturi
Published: July 2013

We subjected
Staphylococcus aureus
ATCC 29213 to serial passage in the presence of subinhibitory concentrations of magainin 2 and gramicidin D for several hundred generations. We obtained
S. aureus
strains with induced resistance to magainin 2 (strain 55MG) and gramicidin D (strain 55GR) that showed different phenotypic changes in membrane properties. Both exhibited a change in membrane phospholipid content and an increase in membrane rigidity, while an alteration in net charge compared to that of the control occurred only in the case of 55MG.
A Peptide Inhibitor of Cytomegalovirus Infection from Human Hemofiltrate
Authors: Borst Eva Maria , Ständker Ludger , Wagner Karen , Schulz Thomas F. , Forssmann Wolf-Georg , Messerle Martin
Published: July 2013

Naturally occurring substances with antimicrobial activity can serve as a starting point for the rational design of new drugs to treat infectious diseases. Here, we screened a library of peptides derived from human hemofiltrate for inhibitory effects on human cytomegalovirus (CMV) infection. We isolated a previously unknown derivative of the neutrophil-activating peptide 2, which we termed CYVIP, for CMV-inhibiting peptide. The peptide blocked infection with human and mouse CMV as well as with herpes simplex virus type 1 in different cell types. We found that CYVIP interferes with virus attachment to the cell surface, and structure-activity relationship studies revealed that positively charged lysine and arginine residues of CYVIP are essential for its inhibitory activity. The N-terminal 29 amino acids of the peptide were sufficient for inhibition, and substitution with an acidic residue further improved its activity. The target structure of CYVIP on the cell surface seems to be the sulfate residues of heparan sulfate proteoglycans, which are known to serve as herpesvirus attachment receptors. Our data suggest that O-sulfation of heparan sulfate is required for binding of CYVIP, and furthermore, that the initial interaction of CMV particles with cells takes place preferentially via 6-O-linked sulfate groups. These findings about CYVIP's mode of action lay the basis for further development of antivirals interfering with attachment of CMV to cells, a crucial step of the infection cycle.
KPC-Producing, Multidrug-Resistant Klebsiella pneumoniae Sequence Type 258 as a Typical Opportunistic Pathogen
Authors: Tzouvelekis L. S. , Miriagou V. , Kotsakis S. D. , Spyridopoulou K. , Athanasiou E. , Karagouni E. , Tzelepi E. , Daikos G. L.
Published: July 2013

The virulence of a KPC-producing
Klebsiella pneumoniae
sequence type 258 (ST258) strain representing those circulating in Greece was assessed in a mouse septicemia model. The strain was virtually avirulent (50% lethal dose, >10
8
and 5 × 10
7
CFU for immunocompetent and neutropenic animals, respectively). Also, it was highly susceptible to serum killing, rapidly phagocytosed
in vitro
, and classified as K41, which is not among the virulent capsular types. The findings indirectly support the notion that high ST258-associated mortality is largely due to inefficient antimicrobial treatment.
Matrix Metalloproteinases 2 and 9 Are Differentially Expressed in Patients with Indeterminate and Cardiac Clinical Forms of Chagas Disease
Authors: Fares Rafaelle Christine Gomes , Gomes Juliana de Assis Silva , Garzoni Luciana Ribeiro , Waghabi Mariana Caldas , Saraiva Roberto Magalhães , Medeiros Nayara Ingrid , Oliveira-Prado Roberta , Sangenis Luiz Henrique Conde , Chambela Mayara da Costa , de Araújo Fernanda Fortes , Teixeira-Carvalho Andréa , Damásio Marcos Paulo , Valente Vanessa Azevedo , Ferreira Karine Silvestre , Sousa Giovane Rodrigo , Rocha Manoel Otávio da Costa , Correa-Oliveira Rodrigo
Published: July 2013

Dilated chronic cardiomyopathy (DCC) from Chagas disease is associated with myocardial remodeling and interstitial fibrosis, resulting in extracellular matrix (ECM) changes. In this study, we characterized for the first time the serum matrix metalloproteinase 2 (MMP-2) and MMP-9 levels, as well as their main cell sources in peripheral blood mononuclear cells from patients presenting with the indeterminate (IND) or cardiac (CARD) clinical form of Chagas disease. Our results showed that serum levels of MMP-9 are associated with the severity of Chagas disease. The analysis of MMP production by T lymphocytes showed that CD8
+
T cells are the main mononuclear leukocyte source of both MMP-2 and MMP-9 molecules. Using a new 3-dimensional model of fibrosis, we observed that sera from patients with Chagas disease induced an increase in the extracellular matrix components in cardiac spheroids. Furthermore, MMP-2 and MMP-9 showed different correlations with matrix proteins and inflammatory cytokines in patients with Chagas disease. Our results suggest that MMP-2 and MMP-9 show distinct activities in Chagas disease pathogenesis. While MMP-9 seems to be involved in the inflammation and cardiac remodeling of Chagas disease, MMP-2 does not correlate with inflammatory molecules.
Transcriptome Analysis of Mouse Brain Infected with Toxoplasma gondii
Authors: Tanaka Sachi , Nishimura Maki , Ihara Fumiaki , Yamagishi Junya , Suzuki Yutaka , Nishikawa Yoshifumi
Published: July 2013

Toxoplasma gondiiis an obligate intracellular parasite that invades a wide range of vertebrate host cells. Chronic infections withT. gondiibecome established in the tissues of the central nervous system, where the parasites may directly or indirectly modulate neuronal function. However, the mechanisms underlying parasite-induced neuronal disorder in the brain remain unclear. This study evaluated host gene expression in mouse brain following infection withT. gondii. BALB/c mice were infected with the PLK strain, and after 32 days of infection, histopathological lesions in the frontal lobe were found to be more severe than in other areas of the brain. Total RNA extracted from infected and uninfected mouse brain samples was subjected to transcriptome analysis using RNA sequencing (RNA-seq). In theT. gondii-infected mice, 935 mouse brain genes were upregulated, whereas 12 genes were downregulated. GOstat analysis predicted that the upregulated genes were primarily involved in host immune responses and cell activation. Positive correlations were found between the numbers of parasites in the infected mouse brains and the expression levels of genes involved in host immune responses. In contrast, genes that had a negative correlation with parasite numbers were predicted to be involved in neurological functions, such as small-GTPase-mediated signal transduction and vesicle-mediated transport. Furthermore, differential gene expression was observed between mice exhibiting the clinical signs of toxoplasmosis and those that did not. Our findings may provide insights into the mechanisms underlying neurological changes duringT. gondiiinfection.
A simple and inexpensive retainer for overdenture prosthesis
Authors: Kumar Lakshya , Rao Jitendra , Yadav Akanksha
Published: July 2013

This article describes a clinical case report of a 65-year-old male patient in which an overdenture was fabricated by using a simple, logical and inexpensive means of retentive device. The described mandibular overdenture involves a simple modification in the coping design and a wire lock mechanism which was fabricated during denture processing. The problems associated with copings were overcome by putting the patient on a regimen wherein topical fluoride was applied every week on the abutment. The denture, fabricated involving a wire lock mechanism, was highly retentive and stable. Patient was highly satisfied with the outcome of the treatment.
Sepsis mimicking thyroid storm in a patient with methimazole-induced agranulocytosis
Authors: Rayner Samuel G , Hosseini Faegheh , Adedipe Adeyinka A
Published: July 2013

Agranulocytosis is a rare yet life-threatening complication of methimazole therapy for hyperthyroidism. We present the case of a 37-year-old female recently started on methimazole for hyperthyroidism who presented to our facility for evaluation of suspected thyroid storm. In addition to having abnormal thyroid indices, she was noted to have an odontogenic abscess, and was septic with profound neutropenia. Her symptoms resolved quickly following incision and drainage of her abscess and treatment with broad-spectrum antibiotics. Her neutrophil count improved significantly following cessation of methimazole and administration of granulocyte colony-stimulating factor. Diagnosis was initially confounded by the similarity between symptoms of early sepsis and those of thyroid storm. This case report discusses the factors leading to diagnostic delay and highlights the dangerous manifestations of neutropenia in patients on methimazole therapy.
Incidence and spread of Heterobasidion root rot in uneven-aged Norway spruce stands
Authors: Piri Tuula , Valkonen Sauli
Published: July 2013

Notwithstanding Norway spruce (Picea abies (L.) Karst.) is highly prone to root rot caused by Heterobasidion parviporum Niemelä & Korhonen, but little is known about the epidemiology of Heterobasidion root rot in spruce stands applied to uneven-aged management. To get insight into the development of Heterobasidion infections in this type of forest, the size and spatial distribution of individual genets of H. parviporum were determined in five uneven-aged managed Norway spruce stands in southern Finland. In these stands, all tree size classes (regeneration, intermediate, and overstory trees) were infected by H. parviporum. The average number of trees and stumps infected by a single genet ranged from 3 to 6.3 (mean 4.4) among study plots. All Heterobasidion genets identified from overstory trees or stumps had spread to the younger tree generation. Secondary infection from overstory trees was the main way of infection (at least 85% of all infections) among the regeneration and intermediate trees. The results indicate that uneven-aged management strategies that maintain continuous spruce regeneration favour the secondary spread of H. parviporum between different tree size classes and may compromise the production of high-quality timber over successive generations.
Effect of growth rate on the natural durability of Douglas-fir in western Europe
Authors: Pollet C. , Henin J.M. , Hébert J. , Jourez B.
Published: July 2013

Douglas-fir is a relatively recent species in the central European forest landscape. It is not clear how its natural durability is influenced by silviculture. We therefore investigated how the natural durability of the Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) varies according to tree growth rate; subsequently, the influence of the nature of the wood (juvenile or mature) and radial position was also analyzed. For this purposes, a total of 60 trees grown in Wallonia (Southern Belgium) was felled: these consisted of 6 trees in each of 10 stands where the average tree girth was approximately 150 cm. Since the age of these plantations ranged from 40 to 69 years, the radial tree growth rate ranged between approximately 3 and 7 mm. In all the trees, standardized heartwood test specimens were taken from different radial positions in the butt log. The mass losses caused by the fungi Poria placenta and Coniophora puteana were assessed according to CEN/TS 15083-1 (2005). Poria placenta exhibited a higher decaying efficiency than C. puteana, leading to classify Douglas-fir wood as slightly durable (class 4). No difference was observed between the durability against P. placenta of juvenile and mature wood. Similarly, growth rate seemed to have no direct impact on durability. Durability was, however, significantly correlated with wood density. The effect of site and tree on the natural durability of the wood was also examined.
Effects of tumor necrosis factor α on leptin-sensitive intestinal vagal mechanoreceptors in the cat
Authors: Quinson Nathalie , Vitton Véronique , Bouvier Michel , Grimaud Jean-Charles , Abysique Anne
Published: July 2013

The involvement of tumour necrosis factor α (TNF-α) in inflammatory bowel disease (IBD) has been established, and anti-TNF-α has been suggested as a therapeutic approach for the treatment of these pathologies. We studied the effects of TNF-α on leptin-sensitive intestinal vagal units to determine whether TNF-α exerts its effects through the intestinal vagal mechanoreceptors and to investigate its interactions with substances regulating food intake. The activity of intestinal vagal mechanoreceptors was recorded via microelectrodes implanted into the nodose ganglion in anesthetized cats. TNF-α (1 μg, i.a.) increased the discharge frequency of leptin-activated units (type 1 units; P < 0.05) and had no effect on the discharge frequency of leptin-inhibited units (type 2 units). When TNF-α was administered 20 min after sulfated cholecystokinin-8 (CCK), its excitatory effects on type 1 units were significantly enhanced (P < 0.0001) and type 2 units were significantly (P < 0.05) activated. Pre-treatment with Il-1ra (250 μg, i.a.) blocked the excitatory effects of TNF-α on type 1 units whereas the excitatory effects of TNF-α administration after CCK treatment on type 2 units were not modified. The activation of leptin-sensitive units by TNF-α may explain, at least in part, the weight loss observed in IBD.
FACILITY MANAGEMENT BENCHMARKING: AN APPLICATION OF DATA ENVELOPMENT ANALYSIS IN HONG KONG
Authors: WONG PHILIP Y. L. , LEUNG STEPHEN C. H. , GILLEARD JOHN D.
Published: July 2013

This paper proposes Data Envelopment Analysis (DEA) as a suitable data analysis tool to overcome facility management (FM) benchmarking difficulties: FM performance benchmarking analysis is often unsophisticated, relying heavily on simple statistical representation, linking hard cost data with soft customer satisfaction data is often problematic. A case study is presented to show that DEA can provide FM personnel with an objective view on performance improvements. An objective of the case study is to investigate the relative efficiency of nine facilities with the same goals and to determine the most efficient facility. The case is limited to nine buildings in FM on four inputs and nine output criteria. The paper concludes by demonstrating that DEA-generated improvement targets can be applied when formulating FM outsourcing policies, strategies and improvements. Facility manager can apply DEA-generated improvement targets in formulating FM outsourcing policies, specifications development, FM strategy and planning. FM benchmarking with DEA can enhance continuous improvement in services' efficiency and cost saving. This will help reduce utility cost as well as pollution. This paper fills the gap in the research of FM benchmarking by applying DEA which studies both soft and hard data, simultaneously. It also contributes to a future research of a tradeoff sensitivity test between FM cost, services performance and reliability.
WATERMARK DETECTION USING DYNAMIC STOCHASTIC RESONANCE
Authors: JHA RAJIB KUMAR , CHATURVEDI APOORV , CHOUHAN RAJLAXMI
Published: July 2013

In this paper, a dynamic stochastic resonance (DSR) based watermark detection technique in discrete wavelet transform (DWT) domain is presented. Pseudo random bit sequence having certain seed value is considered as a watermark. Watermark embedding is done by embedding random bits in spread-spectrum fashion to the significant DWT coefficients. Watermark detection is quantitatively characterized by the value of correlation. The performance of watermark detection is improved by DSR which is an iterative process that utilizes the internal noise present in the image or external noise which is added during attacks. Even under various noise attacks, geometrical distortions, image enhancement and compression attacks, the DSR-based random bits detection is observed to give noteworthy improvement over existing watermark detection techniques. DSR-based technique is also found to give better detection performance when compared with the suprathreshold stochastic resonance-based detection technique.
A NEW PARADIGM FOR THE IN VITRO SIMULATION OF SIDEWAYS FALL LOADING OF THE PROXIMAL HUMAN FEMUR
Authors: ZANI LORENZO , CRISTOFOLINI LUCA , JUSZCZYK MATEUSZ MARIA , GRASSI LORENZO , VICECONTI MARCO
Published: July 2013

Although the direction of loads applied to the proximal human femur is unpredictable during sideways fall, most in vitro and numerical simulations refer to a single loading condition (15° internal rotation; 10° adduction), which has been anecdotally suggested in the 1950s. The aim of the present study was to improve in vitro simulations of sideways falls on the proximal femur.

An in vitro setup was developed that allowed exploring a range of loading directions +/-90° internal–external rotation; 0°–50° adduction). To enable accurate control of the loading conditions (direction and magnitude of all load components applied to the femur), the setup included a number of low-friction linear and rotary bearings. The setup was instrumented with an axial and a torsional load cell, three displacement transducers and a rotation transducer to monitor the most significant components of load/displacement during testing. The strain distribution was measured on the bone surface (16 triaxial strain gauges, 2,000 Hz). Fracture was recorded with a high-speed camera.

The setup was successfully tested on a cadaveric femur non-destructively (12 loading configurations) and destructively (15° internal rotation; 10° adduction). All measurements were highly repeatable (the displacements of the femoral head varied by < 2% between repetitions; the tilt in the frontal plane by < 0.05°; and strain varied on average 0.34% between repetitions). The displacement of the femoral head varied by over 50% when the same force was applied in different directions. Principal strains at the same location varied by over 70%, depending on the direction of the applied force. The high-speed video enabled the identification of the point of fracture initiation.

This study has shown that a new paradigm for testing the proximal femur (including improved testing conditions and a variety of loading configurations) can provide more accurate and more extensive information about the state of strain.
SLANT SUBMANIFOLDS OF SEMI-RIEMANNIAN MANIFOLDS
Authors: AYDIN GÜLŞAH , ÇÖKEN A. CEYLAN
Published: July 2013

In this study, we search slant submanifolds of almost product semi-Riemannian manifold. Accordingly, we investigate slant submanifolds of semi-Riemannian manifold by making the classifications as slant Riemannian, slant semi-Riemannian and slant lightlike submanifold. Moreover, we add the theorems which characterize existence of slant submanifold.
WHAT DO EXPERTS KNOW ABOUT FORECASTING JOURNAL QUALITY? A COMPARISON WITH ISI RESEARCH IMPACT IN FINANCE
Authors: CHANG CHIA-LIN , MCALEER MICHAEL
Published: July 2013

Experts possess knowledge and information that are not publicly available. The paper is concerned with forecasting academic journal quality and research impact using a survey of international experts from a national project on ranking academic finance journals in Taiwan. A comparison is made with publicly available bibliometric data, namely the Thomson Reuters ISI Web of Science citations database (hereafter ISI) for the Business–Finance (hereafter Finance) category. The paper analyses the leading international journals in Finance using expert scores and quantifiable Research Assessment Measures (RAMs), and highlights the similarities and differences in the expert scores and alternative RAMs, where the RAMs are based on alternative transformations of citations taken from the ISI database. Alternative RAMs may be calculated annually or updated daily to answer the perennial questions as to When, Where and How (frequently) published papers are cited (see Chang et al., 2011a,b,c). The RAMs include the most widely used RAM, namely the classic 2-year impact factor including journal self citations (2YIF), 2-year impact factor excluding journal self citations (2YIF*), 5-year impact factor including journal self citations (5YIF), Immediacy (or zero-year impact factor (0YIF)), Eigenfactor, Article Influence, C3PO (Citation Performance per Paper Online), h-index, PI-BETA (Papers Ignored — By even the Authors), 2-year Self-citation Threshold Approval Ratings (2Y-STAR), Historical Self-citation Threshold Approval Ratings (H-STAR), Impact Factor Inflation (IFI), and Cited Article Influence (CAI). As data are not available for 5YIF, Article Influence and CAI for 13 of the leading 34 journals considered, 10 RAMs are analysed for 21 highly-cited journals in Finance. The harmonic mean of the ranks of the 10 RAMs for the 34 highly-cited journals are also presented. It is shown that emphasizing the 2-year impact factor of a journal, which partly answers the question as to When published papers are cited, to the exclusion of other informative RAMs, which answer Where and How (frequently) published papers are cited, can lead to a distorted evaluation of journal impact and influence relative to the Harmonic Mean rankings. A linear regression model is used to forecast expert scores on the basis of RAMs that capture journal impact, journal policy, the number of high quality papers, and quantitative information about a journal. The robustness of the rankings is also analyzed.
L
1
-medial skeleton of point cloud
Authors: Huang Hui , Wu Shihao , Cohen-Or Daniel , Gong Minglun , Zhang Hao , Li Guiqing , Chen Baoquan
Published: July 2013

We introduce
L
1
-
medial skeleton
as a curve skeleton representation for 3D point cloud data. The
L
1
-median is well-known as a robust global center of an arbitrary set of points. We make the key observation that adapting
L
1
-medians
locally
to a point set representing a 3D shape gives rise to a one-dimensional structure, which can be seen as a localized center of the shape. The primary advantage of our approach is that it does not place strong requirements on the quality of the input point cloud nor on the geometry or topology of the captured shape. We develop a
L
1
-medial skeleton construction algorithm, which can be directly applied to an unoriented raw point scan with significant noise, outliers, and large areas of missing data. We demonstrate
L
1
-medial skeletons extracted from raw scans of a variety of shapes, including those modeling high-genus 3D objects, plant-like structures, and curve networks.
Dense scene reconstruction with points of interest
Authors: Zhou Qian-Yi , Koltun Vladlen
Published: July 2013

We present an approach to detailed reconstruction of complex real-world scenes with a handheld commodity range sensor. The user moves the sensor freely through the environment and images the scene. An offline registration and integration pipeline produces a detailed scene model. To deal with the complex sensor trajectories required to produce detailed reconstructions with a consumer-grade sensor, our pipeline detects points of interest in the scene and preserves detailed geometry around them while a global optimization distributes residual registration errors through the environment. Our results demonstrate that detailed reconstructions of complex scenes can be obtained with a consumer-grade camera.
Layered analysis of irregular facades via symmetry maximization
Authors: Zhang Hao , Xu Kai , Jiang Wei , Lin Jinjie , Cohen-Or Daniel , Chen Baoquan
Published: July 2013

We present an algorithm for
hierarchical
and
layered
analysis of
irregular
facades, seeking a high-level understanding of facade structures. By introducing layering into the analysis, we no longer view a facade as a flat structure, but allow it to be structurally separated into depth layers, enabling more compact and natural interpretations of building facades. Computationally, we perform a symmetry-driven search for an optimal hierarchical decomposition defined by split and layering operations applied to an input facade. The objective is
symmetry maximization
, i.e., to maximize the sum of symmetry of the substructures resulting from recursive decomposition. To this end, we propose a novel
integral symmetry
measure, which behaves well at both ends of the symmetry spectrum by accounting for all partial symmetries in a discrete structure. Our analysis results in a structural representation, which can be utilized for structural editing and exploration of building facades.
Scene reconstruction from high spatio-angular resolution light fields
Authors: Kim Changil , Zimmer Henning , Pritch Yael , Sorkine-Hornung Alexander , Gross Markus
Published: July 2013

This paper describes a method for scene reconstruction of complex, detailed environments from 3D light fields. Densely sampled light fields in the order of 10
9
light rays allow us to capture the real world in unparalleled detail, but efficiently processing this amount of data to generate an equally detailed reconstruction represents a significant challenge to existing algorithms. We propose an algorithm that leverages coherence in massive light fields by breaking with a number of established practices in image-based reconstruction. Our algorithm first computes reliable depth estimates specifically around object boundaries instead of interior regions, by operating on
individual light rays
instead of image patches. More homogeneous interior regions are then processed in a
fine-to-coarse
procedure rather than the standard coarse-to-fine approaches. At no point in our method is any form of global optimization performed. This allows our algorithm to retain precise object contours while still ensuring smooth reconstructions in less detailed areas. While the core reconstruction method handles general unstructured input, we also introduce a
sparse representation
and a
propagation scheme
for reliable depth estimates which make our algorithm particularly effective for 3D input, enabling fast and memory efficient processing of "Gigaray light fields" on a standard GPU. We show dense 3D reconstructions of highly detailed scenes, enabling applications such as automatic segmentation and image-based rendering, and provide an extensive evaluation and comparison to existing image-based reconstruction techniques.
A reconfigurable camera add-on for high dynamic range, multispectral, polarization, and light-field imaging
Authors: Manakov Alkhazur , Restrepo John F. , Klehm Oliver , Hegedüs Ramon , Eisemann Elmar , Seidel Hans-Peter , Ihrke Ivo
Published: July 2013

We propose a non-permanent add-on that enables plenoptic imaging with standard cameras. Our design is based on a physical copying mechanism that multiplies a sensor image into a number of identical copies that still carry the plenoptic information of interest. Via different optical filters, we can then recover the desired information. A minor modification of the design also allows for aperture sub-sampling and, hence, light-field imaging. As the filters in our design are exchangeable, a reconfiguration for different imaging purposes is possible. We show in a prototype setup that high dynamic range, multispectral, polarization, and light-field imaging can be achieved with our design.
MeshGit
Authors: Denning Jonathan D. , Pellacini Fabio
Published: July 2013

This paper presentsMeshGit, a practical algorithm for diffing and merging polygonal meshes typically used in subdivision modeling workflows. Inspired by version control for text editing, we introduce themesh edit distanceas a measure of the dissimilarity between meshes. This distance is defined as the minimum cost of matching the vertices and faces of one mesh to those of another. We propose an iterative greedy algorithm to approximate the mesh edit distance, which scales well with model complexity, providing a practical solution to our problem. We translate the mesh correspondence into a set of mesh editing operations that transforms the first mesh into the second. The editing operations can be displayed directly to provide a meaningful visual difference between meshes. For merging, we compute the difference between two versions and their common ancestor, as sets of editing operations. We robustly detect conflicting operations, automatically apply non-conflicting edits, and allow the user to choose how to merge the conflicting edits. We evaluateMeshGitby diffing and merging a variety of meshes and find it to work well for all.
Particle-based anisotropic surface meshing
Authors: Zhong Zichun , Guo Xiaohu , Wang Wenping , Lévy Bruno , Sun Feng , Liu Yang , Mao Weihua
Published: July 2013

This paper introduces a particle-based approach for anisotropic surface meshing. Given an input polygonal mesh endowed with a Riemannian metric and a specified number of vertices, the method generates a metric-adapted mesh. The main idea consists of mapping the anisotropic space into a higher dimensional isotropic one, called "embedding space". The vertices of the mesh are generated by uniformly sampling the surface in this higher dimensional embedding space, and the sampling is further regularized by optimizing an energy function with a quasi-Newton algorithm. All the computations can be re-expressed in terms of the dot product in the embedding space, and the Jacobian matrices of the mappings that connect different spaces. This transform makes it unnecessary to explicitly represent the coordinates in the embedding space, and also provides all necessary expressions of energy and forces for efficient computations. Through energy optimization, it naturally leads to the desired anisotropic particle distributions in the original space. The triangles are then generated by computing the Restricted Anisotropic Voronoi Diagram and its dual Delaunay triangulation. We compare our results qualitatively and quantitatively with the state-of-the-art in anisotropic surface meshing on several examples, using the standard measurement criteria.
Axis-aligned filtering for interactive physically-based diffuse indirect lighting
Authors: Mehta Soham Uday , Wang Brandon , Ramamoorthi Ravi , Durand Fredo
Published: July 2013

We introduce an algorithm for interactive rendering of physically-based global illumination, based on a novel frequency analysis of indirect lighting. Our method combines adaptive sampling by Monte Carlo ray or path tracing, using a standard GPU-accelerated raytracer, with real-time reconstruction of the resulting noisy images. Our theoretical analysis assumes diffuse indirect lighting, with general Lambertian and specular receivers. In practice, we demonstrate accurate interactive global illumination with diffuse and moderately glossy objects, at 1-3 fps. We show mathematically that indirect illumination is a structured signal in the Fourier domain, with inherent band-limiting due to the BRDF and geometry terms. We extend previous work on sheared and axis-aligned filtering for motion blur and shadows, to develop an image-space filtering method for interreflections. Our method enables 5--8X reduced sampling rates and wall clock times, and converges to ground truth as more samples are added. To develop our theory, we overcome important technical challenges---unlike previous work, there is no light source to serve as a band-limit in indirect lighting, and we also consider non-parallel geometry of receiver and reflecting surfaces, without first-order approximations.
Two-layer sparse compression of dense-weight blend skinning
Authors: Le Binh Huy , Deng Zhigang
Published: July 2013

Weighted linear interpolation has been widely used in many skinning techniques including linear blend skinning, dual quaternion blend skinning, and cage based deformation. To speed up performance, these skinning models typically employ a sparseness constraint, in which each 3D model vertex has a small fixed number of non-zero weights. However, the sparseness constraint also imposes certain limitations to skinning models and their various applications. This paper introduces an efficient two-layer sparse compression technique to substantially reduce the computational cost of a dense-weight skinning model, with insignificant loss of its visual quality. It can directly work on dense skinning weights or use example-based skinning decomposition to further improve its accuracy. Experiments and comparisons demonstrate that the introduced sparse compression model can significantly outperform state of the art weight reduction algorithms, as well as skinning decomposition algorithms with a sparseness constraint.
Radial view based culling for continuous self-collision detection of skeletal models
Authors: Wong Sai-Keung , Lin Wen-Chieh , Hung Chun-Hung , Huang Yi-Jheng , Lii Shing-Yeu
Published: July 2013

We present a novel radial-view-based culling method for continuous self-collision detection (CSCD) of skeletal models. Our method targets closed triangular meshes used to represent the surface of a model. It can be easily integrated with bounding volume hierarchies (BVHs) and used as the first stage for culling non-colliding triangle pairs. A mesh is decomposed into clusters with respect to a set of observer primitives (i.e., observer points and line segments) on the skeleton of the mesh so that each cluster is associated with an observer primitive. One BVH is then built for each cluster. At the runtime stage, a radial view test is performed from the observer primitive of each cluster to check its collision state. Every pair of clusters is also checked for collisions. We evaluated our method on various models and compared its performance with prior methods. Experimental results show that our method reduces the number of the bounding volume overlapping tests and the number of potentially colliding triangle pairs, thereby improving the overall process of CSCD.
Map-based exploration of intrinsic shape differences and variability
Authors: Rustamov Raif M. , Ovsjanikov Maks , Azencot Omri , Ben-Chen Mirela , Chazal Frédéric , Guibas Leonidas
Published: July 2013

We develop a novel formulation for the notion of shape differences, aimed at providing detailed information about the location and nature of the differences or distortions between the two shapes being compared. Our difference operator, derived from a shape map, is much more informative than just a scalar global shape similarity score, rendering it useful in a variety of applications where more refined shape comparisons are necessary. The approach is intrinsic and is based on a linear algebraic framework, allowing the use of many common linear algebra tools (e.g, SVD, PCA) for studying a matrix representation of the operator. Remarkably, the formulation allows us not only to localize shape differences on the shapes involved, but also to compare shape differences across pairs of shapes, and to analyze the variability in entire shape collections based on the differences between the shapes. Moreover, while we use a map or correspondence to define each shape difference, consistent correspondences between the shapes are not necessary for comparing shape differences, although they can be exploited if available. We give a number of applications of shape differences, including parameterizing the intrinsic variability in a shape collection, exploring shape collections using local variability at different scales, performing shape analogies, and aligning shape collections.
Perception of perspective distortions in image-based rendering
Authors: Vangorp Peter , Richardt Christian , Cooper Emily A. , Chaurasia Gaurav , Banks Martin S. , Drettakis George
Published: July 2013

Image-based rendering (IBR) creates realistic images by enriching simple geometries with photographs, e.g., mapping the photograph of a building façade onto a plane. However, as soon as the viewer moves away from the correct viewpoint, the image in the retina becomes distorted, sometimes leading to gross misperceptions of the original geometry. Two hypotheses from vision science state how viewers perceive such image distortions, one claiming that they can compensate for them (and therefore perceive scene geometry reasonably correctly), and one claiming that they cannot compensate (and therefore can perceive rather significant distortions). We modified the latter hypothesis so that it extends to street-level IBR. We then conducted a rigorous experiment that measured the magnitude of perceptual distortions that occur with IBR for façade viewing. We also conducted a rating experiment that assessed the acceptability of the distortions. The results of the two experiments were consistent with one another. They showed that viewers' percepts are indeed distorted, but not as severely as predicted by the modified vision science hypothesis. From our experimental results, we develop a predictive model of distortion for street-level IBR, which we use to provide guidelines for acceptability of virtual views and for capture camera density. We perform a confirmatory study to validate our predictions, and illustrate their use with an application that guides users in IBR navigation to stay in regions where virtual views yield acceptable perceptual distortions.
User-assisted image compositing for photographic lighting
Authors: Boyadzhiev Ivaylo , Paris Sylvain , Bala Kavita
Published: July 2013

Good lighting is crucial in photography and can make the difference between a great picture and a discarded image. Traditionally, professional photographers work in a studio with many light sources carefully set up, with the goal of getting a near-final image at exposure time, with post-processing mostly focusing on aspects orthogonal to lighting. Recently, a new workflow has emerged for architectural and commercial photography, where photographers capture several photos from a fixed viewpoint with a moving light source. The objective is not to produce the final result immediately, but rather to capture useful data that are later processed, often significantly, in photo editing software to create the final well-lit image.

This new workflow is flexible, requires less manual setup, and works well for time-constrained shots. But dealing with several tens of unorganized layers is painstaking, requiring hours to days of manual effort, as well as advanced photo editing skills. Our objective in this paper is to make the compositing step easier. We describe a set of optimizations to assemble the input images to create a fewbasis lightsthat correspond to common goals pursued by photographers, e.g., accentuating edges and curved regions. We also introducemodifiersthat capture standard photographic tasks, e.g., to alter the lights to soften highlights and shadows, akin to umbrellas and soft boxes. Our experiments with novice and professional users show that our approach allows them to quickly create satisfying results, whereas working with unorganized images requires considerably more time. Casual users particularly benefit from our approach since coping with a large number of layers is daunting for them and requires significant experience.
Online modeling for realtime facial animation
Authors: Bouaziz Sofien , Wang Yangang , Pauly Mark
Published: July 2013

We present a new algorithm for realtime face tracking on commodity RGB-D sensing devices. Our method requires no user-specific training or calibration, or any other form of manual assistance, thus enabling a range of new applications in performance-based facial animation and virtual interaction at the consumer level. The key novelty of our approach is an optimization algorithm that jointly solves for a detailed 3D expression model of the user and the corresponding dynamic tracking parameters. Realtime performance and robust computations are facilitated by a novel subspace parameterization of the dynamic facial expression space. We provide a detailed evaluation that shows that our approach significantly simplifies the performance capture workflow, while achieving accurate facial tracking for realtime applications.
Highly adaptive liquid simulations on tetrahedral meshes
Authors: Ando Ryoichi , Thürey Nils , Wojtan Chris
Published: July 2013

We introduce a new method for efficiently simulating liquid with extreme amounts of spatial adaptivity. Our method combines several key components to drastically speed up the simulation of large-scale fluid phenomena: We leverage an alternative Eulerian tetrahedral mesh discretization to significantly reduce the complexity of the pressure solve while increasing the robustness with respect to element quality and removing the possibility of locking. Next, we enable subtle free-surface phenomena by deriving novel second-order boundary conditions consistent with our discretization. We couple this discretization with a spatially adaptive Fluid-Implicit Particle (FLIP) method, enabling efficient, robust, minimally-dissipative simulations that can undergo sharp changes in spatial resolution while minimizing artifacts. Along the way, we provide a new method for generating a smooth and detailed surface from a set of particles with variable sizes. Finally, we explore several new sizing functions for determining spatially adaptive simulation resolutions, and we show how to couple them to our simulator. We combine each of these elements to produce a simulation algorithm that is capable of creating animations at high maximum resolutions while avoiding common pitfalls like inaccurate boundary conditions and inefficient computation.