bluuebunny/crossref_metadata_2025 huggingface dataset:
Absorption and frequency shift of GPR signals in sandy and silty soils: empirical relations between quality factor Q, complex permittivity and clay and water contents
Authors: Wunderlich Tina , Rabbel Wolfgang
Published: March 2013

The arrival time, shape and amplitude of a reflected GPR wavelet depend mainly on the real and imaginary parts of dielectrical permittivity and electrical conductivity. All these parameters are strongly affected by the water and clay content of soils. From a comparison of the amplitude and shape of the direct and reflected wavelets the quality factor can be determined independently as an additional soil parameter. To investigate the relationships between the influencing factors, we conducted high‐frequency GPR reflection measurements on soil samples with varying clay and water contents. The factor, derived from the spectral ratio method, is found to be between 5–15 for our samples that range from about 5–90% in sand content, 5–65% in silt content, 3–63% in clay content and 0–37% in pore water content. A multivariate non‐linear empirical function linking water and clay content to agrees well with the observations. We found that the ratio of the real and imaginary parts of the dielectric permittivity depends basically on the clay content. Therefore, it may become possible to determine the clay content of soils in situ from a combination of GPR and conductivity measurements. The values determined from spectral ratios are confirmed by synthetic radargrams and agree with the observed decrease of the central frequency of GPR reflections caused by absorption.
2D and 3D ground‐penetrating radar surveys with a modular system: data processing strategies and results from archaeological field tests
Authors: Verdonck Lieven , Vermeulen Frank , Docter Roald , Meyer Cornelius , Kniess Rudolf
Published: March 2013

Recently, the use of ground‐penetrating radar (GPR) arrays with a large number of antenna elements in a fixed configuration has become more common. The investment needed for these systems is significant. In order to reduce the recording time in the field, an alternative is the use of several single GPR antennas in parallel (a ‘modular system’). Although this does not match the fast acquisition of detailed data sets by means of multi‐channel arrays, a system consisting in single antennas can gradually be expanded and investment can be spread over time. This paper presents a 2D and a full‐resolution 3D survey, conducted with a modular GPR instrument. A characteristic of these systems is that the cross‐line separation between transmitter‐receiver pairs is larger than the sampling distance prescribed by the Nyquist theorem. As a consequence, for 3D data collection, profiles have to be acquired between previously recorded ones, which requires high positioning accuracy. A completely identical response for different single GPR antennas is difficult to achieve. For the system tested, on less favourable soils this resulted in striping in the horizontal slices. Several methods (3D frequency‐wavenumber filtering, eigenimage filtering, mean profile filtering and filtering based on discrete wavelet transform, discrete ridgelet transform and linear Radon transform) were applied to two data sets exhibiting different kinds of linear noise and their capability to suppress artefacts was assessed. Although overall a reduction of the stripe patterns was achieved, mostly it was impossible to fully eliminate the noise in the time‐slices without low‐pass filtering in the cross‐line direction. For the 2D data, low‐pass filtering caused loss of some of the archaeological response and therefore was not applied. Mean profile filtering allowed the most reliable characterization of the archaeological structures.
Tolerogenic Donor-Derived Dendritic Cells Risk Sensitization In Vivo owing to Processing and Presentation by Recipient APCs
Authors: Smyth Lesley A. , Ratnasothy Kulachelvy , Moreau Aurelie , Alcock Sally , Sagoo Pervinder , Meader Lucy , Tanriver Yakup , Buckland Matthew , Lechler Robert , Lombardi Giovanna
Published: March 2013

Modification of allogeneic dendritic cells (DCs) through drug treatment results in DCs with in vitro hallmarks of tolerogenicity. Despite these observations, using murine MHC-mismatched skin and heart transplant models, donor-derived drug-modified DCs not only failed to induce tolerance but also accelerated graft rejection. The latter was inhibited by injecting the recipient with anti-CD8 Ab, which removed both CD8+ T cells and CD8+ DCs. The discrepancy between in vitro and in vivo data could be explained, partly, by the presentation of drug-modified donor DC MHC alloantigens by recipient APCs and activation of recipient T cells with indirect allospecificity, leading to the induction of alloantibodies. Furthermore, allogeneic MHC molecules expressed by drug-treated DCs were rapidly processed and presented in peptide form by recipient APCs in vivo within hours of DC injection. Using TCR-transgenic T cells, Ag presentation of injected OVA-pulsed DCs was detectable for ≤ 3 d, whereas indirect presentation of MHC alloantigen by recipient APCs led to activation of T cells within 14 h and was partially inhibited by reducing the numbers of CD8+ DCs in vivo. In support of this observation when mice lacking CD8+ DCs were pretreated with drug-modified DCs prior to transplantation, skin graft rejection kinetics were similar to those in non–DC-treated controls. Of interest, when the same mice were treated with anti-CD40L blockade plus drug-modified DCs, skin graft survival was prolonged, suggesting endogenous DCs were responsible for T cell priming. Altogether, these findings highlight the risks and limitations of negative vaccination using alloantigen-bearing “tolerogenic” DCs.
GITR-Dependent Regulation of 4-1BB Expression: Implications for T Cell Memory and Anti–4-1BB–Induced Pathology
Authors: Lin Gloria H. Y. , Snell Laura M. , Wortzman Michael E. , Clouthier Derek L. , Watts Tania H.
Published: March 2013

The TNFR family member 4-1BB plays a key role in the survival of activated and memory CD8 T cells. However, the mechanisms that regulate 4-1BB re-expression on memory CD8 T cells after Ag clearance are unknown. In unimmunized mice, ∼10% of CD8 CD44hi memory T cells in the bone marrow (BM) and liver express 4-1BB, with minimal 4-1BB expression in spleen and lymph node. IL-2, IL-15, and IL-7 are collectively dispensable for 4-1BB expression on the memory CD8 T cells. Rather, T cell–intrinsic glucocorticoid-induced TNFR-related protein (GITR) contributes to 4-1BB expression on CD8 T cells upon their entry into the BM or liver. Consistent with its role in regulation of 4-1BB, GITR is required on memory CD8 T cells for their persistence in vivo. These findings reveal site-specific effects of the BM and liver microenvironment on CD8 memory T cells. Previous work has demonstrated that 4-1BB agonists given to unimmunized mice induce splenomegaly, hepatitis, and other immune system anomalies. Moreover, severe liver pathology has been observed in a subset of anti–4-1BB–treated melanoma patients. Remarkably, the absence of GITR in mice almost completely abrogates cellular expansions, splenomegaly, and liver inflammation associated with anti–4-1BB agonist treatment of unimmunized mice. In contrast, lack of CD8 T cells selectively improves liver pathology, but not splenomegaly in the mice. Thus, the regulation of 4-1BB expression by GITR on CD8 T cells, as well as on other cells, contributes to the pathological effects of anti–4-1BB in unimmunized mice.
IL-27 Receptor Signaling Regulates CD4+ T Cell Chemotactic Responses during Infection
Authors: Gwyer Findlay Emily , Villegas-Mendez Ana , de Souza J. Brian , Inkson Colette A. , Shaw Tovah N. , Saris Christiaan J. , Hunter Christopher A. , Riley Eleanor M. , Couper Kevin N.
Published: March 2013

IL-27 exerts pleiotropic suppressive effects on naive and effector T cell populations during infection and inflammation. Surprisingly, however, the role of IL-27 in restricting or shaping effector CD4+ T cell chemotactic responses, as a mechanism to reduce T cell–dependent tissue inflammation, is unknown. In this study, using Plasmodium berghei NK65 as a model of a systemic, proinflammatory infection, we demonstrate that IL-27R signaling represses chemotaxis of infection-derived splenic CD4+ T cells in response to the CCR5 ligands, CCL4 and CCL5. Consistent with these observations, CCR5 was expressed on significantly higher frequencies of splenic CD4+ T cells from malaria-infected, IL-27R–deficient (WSX-1−/−) mice than from infected wild-type mice. We find that IL-27 signaling suppresses splenic CD4+ T cell CCR5-dependent chemotactic responses during infection by restricting CCR5 expression on CD4+ T cell subtypes, including Th1 cells, and also by controlling the overall composition of the CD4+ T cell compartment. Diminution of the Th1 response in infected WSX-1−/− mice in vivo by neutralization of IL-12p40 attenuated CCR5 expression by infection-derived CD4+ T cells and also reduced splenic CD4+ T cell chemotaxis toward CCL4 and CCL5. These data reveal a previously unappreciated role for IL-27 in modulating CD4+ T cell chemotactic pathways during infection, which is related to its capacity to repress Th1 effector cell development. Thus, IL-27 appears to be a key cytokine that limits the CCR5-CCL4/CCL5 axis during inflammatory settings.
Prenatally Acquired Vitamin A Deficiency Alters Innate Immune Responses to Human Rotavirus in a Gnotobiotic Pig Model
Authors: Vlasova Anastasia N. , Chattha Kuldeep S. , Kandasamy Sukumar , Siegismund Christine S. , Saif Linda J.
Published: March 2013

We examined how prenatally acquired vitamin A deficiency (VAD) modulates innate immune responses and human rotavirus (HRV) vaccine efficacy in a gnotobiotic (Gn) piglet model of HRV diarrhea. The VAD and vitamin A–sufficient (VAS) Gn pigs were vaccinated with attenuated HRV (AttHRV) with or without concurrent oral vitamin A supplementation (100,000 IU) and challenged with virulent HRV (VirHRV). Regardless of vaccination status, the numbers of conventional and plasmacytoid dendritic cells (cDCs and pDCs) were higher in VAD piglets prechallenge, but decreased substantially postchallenge as compared with VAS pigs. We observed significantly higher frequency of CD103 (integrin αEβ7) expressing DCs in VAS versus VAD piglets postchallenge, indicating that VAD may interfere with homing (including intestinal) phenotype acquisition. Post-VirHRV challenge, we observed longer and more pronounced diarrhea and higher VirHRV fecal titers in nonvaccinated VAD piglets. Consistent with higher VirHRV shedding titers, higher IFN-α levels were induced in control VAD versus VAS piglet sera at postchallenge day 2. Ex vivo HRV-stimulated mononuclear cells (MNCs) isolated from spleen and blood of VAD pigs prechallenge also produced more IFN-α. In contrast, at postchallenge day 10, we observed reduced IFN-α levels in VAD pigs that coincided with decreased TLR3+ MNC frequencies. Numbers of necrotic MNCs were higher in VAD pigs in spleen (coincident with splenomegaly in other VAD animals) prechallenge and intestinal tissues (coincident with higher VirHRV induced intestinal damage) postchallenge. Thus, prenatal VAD caused an imbalance in innate immune responses and exacerbated VirHRV infection, whereas vitamin A supplementation failed to compensate for these VAD effects.
Id2-Mediated Inhibition of E2A Represses Memory CD8+ T Cell Differentiation
Authors: Masson Frederick , Minnich Martina , Olshansky Moshe , Bilic Ivan , Mount Adele M. , Kallies Axel , Speed Terence P. , Busslinger Meinrad , Nutt Stephen L. , Belz Gabrielle T.
Published: March 2013

The transcription factor inhibitor of DNA binding (Id)2 modulates T cell fate decisions, but the molecular mechanism underpinning this regulation is unclear. In this study we show that loss of Id2 cripples effector differentiation and instead programs CD8+ T cells to adopt a memory fate with increased Eomesodermin and Tcf7 expression. We demonstrate that Id2 restrains CD8+ T cell memory differentiation by inhibiting E2A-mediated direct activation of Tcf7 and that Id2 expression level mirrors T cell memory recall capacity. As a result of the defective effector differentiation, Id2-deficient CD8+ T cells fail to induce sufficient Tbx21 expression to generate short-lived effector CD8+ T cells. Our findings reveal that the Id2/E2A axis orchestrates T cell differentiation through the induction or repression of downstream transcription factors essential for effector and memory T cell differentiation.
Nonstereotyped Lymphoma B Cell Receptors Recognize Vimentin as a Shared Autoantigen
Authors: Cha Soung-Chul , Qin Hong , Kannan Shibichakravarthy , Rawal Seema , Watkins Leticia S. , Baio Flavio E. , Wu Weiguo , Ong Juliana , Wei Jinsong , Kwak Benjamin , Kim Sang , Popescu Michael S. , Paick Daniel S. , Kim Kunhwa , Luong Amber , Davis Richard E. , Schroeder Harry W. , Kwak Larry W. , Neelapu Sattva S.
Published: March 2013

Ag activation of the BCR may play a role in the pathogenesis of human follicular lymphoma (FL) and other B cell malignancies. However, the nature of the Ag(s) recognized by tumor BCRs has not been well studied. In this study, we used unbiased approaches to demonstrate that 42 (19.35%) of 217 tested FL Igs recognized vimentin as a shared autoantigen. The epitope was localized to the N-terminal region of vimentin for all vimentin-reactive tumor Igs. We confirmed specific binding to vimentin by using recombinant vimentin and by performing competitive inhibition studies. Furthermore, using indirect immunofluorescence staining, we showed that the vimentin-reactive tumor Igs colocalized with an anti-vimentin mAb in HEp-2 cells. The reactivity to N-terminal vimentin of IgG FL Igs was significantly higher than that of IgM FL Igs (30.4 versus 10%; p = 0.0022). However, vimentin-reactive FL Igs did not share CDR3 motifs and were not homologous. Vimentin was expressed in the T cell–rich regions of FL, suggesting that vimentin is available for binding with tumor BCRs within the tumor microenvironment. Vimentin was also frequently recognized by mantle cell lymphoma and multiple myeloma Igs. Our results demonstrate that vimentin is a shared autoantigen recognized by nonstereotyped FL BCRs and by the Igs of mantle cell lymphoma and multiple myeloma and suggest that vimentin may play a role in the pathogenesis of multiple B cell malignancies. These findings may lead to a better understanding of the biology and natural history of FL and other B cell malignancies.
Restoring Immune Function of Tumor-Specific CD4+ T Cells during Recurrence of Melanoma
Authors: Goding Stephen R. , Wilson Kyle A. , Xie Ying , Harris Kristina M. , Baxi Aparna , Akpinarli Akgul , Fulton Amy , Tamada Koji , Strome Scott E. , Antony Paul Andrew
Published: March 2013

Recurrent solid malignancies are often refractory to standard therapies. Although adoptive T cell transfer may benefit select individuals, the majority of patients succumb to their disease. To address this important clinical dilemma, we developed a mouse melanoma model in which initial regression of advanced disease was followed by tumor recurrence. During recurrence, Foxp3+ tumor-specific CD4+ T cells became PD-1+ and represented >60% of the tumor-specific CD4+ T cells in the host. Concomitantly, tumor-specific CD4+ T effector cells showed traits of chronic exhaustion, as evidenced by their high expression of the PD-1, TIM-3, 2B4, TIGIT, and LAG-3 inhibitory molecules. Although blockade of the PD-1/PD-L1 pathway with anti–PD-L1 Abs or depletion of tumor-specific regulatory T cells (Tregs) alone failed to reverse tumor recurrence, the combination of PD-L1 blockade with tumor-specific Treg depletion effectively mediated disease regression. Furthermore, blockade with a combination of anti–PD-L1 and anti–LAG-3 Abs overcame the requirement to deplete tumor-specific Tregs. In contrast, successful treatment of primary melanoma with adoptive cell therapy required only Treg depletion or Ab therapy, underscoring the differences in the characteristics of treatment between primary and relapsing cancer. These data highlight the need for preclinical development of combined immunotherapy approaches specifically targeting recurrent disease.
Sanitary risk analysis for farm workers exposed to environmental pollutants
Authors: Pascuzzi Simone , Russo Giovanni , Scarascia-Mugnozza Giacomo , Verdiani Giuseppe
Published: March 2013

In Italy, a large number of agricultural areas are contaminated by organic and inorganic polluting substances. In such areas, the agricultural operators come into contact with the environmental contaminants through inhalation and dermic contact with dusts and vapour, and this exposure can potentially alter the biological equilibrium with consequent poisonings and/or work-related illness. The aim of this paper is to apply a methodological procedure for the numerical evaluation of the health risk for agricultural employees operating in open fields or inside greenhouses located in areas contaminated with organic pollutants. This procedure is in response to the lack of calculation models concerning these types of environment and agricultural activities. As a case study, this methodology has been applied to an agricultural area of southern Italy characterised by the presence of pollutants. The results underline that in this area there is a smaller concentration of pollutants in open field cultivations than inside greenhouses owing to a phenomenon of dispersion into the atmosphere. This numeric analysis will later be verified by measurements carried out in situ in order to evaluate the real situation on the ground.
Scale-up analysis and critical issues of an experimental pilot plant for edible film production using agricultural waste processing
Authors: Sarghini Fabrizio , Di Pierro Prospero , Veneruso Antonio , Masi Paolo
Published: March 2013

This study was developed to test a multifunctional experimental pilot plant with a reduced environmental impact that is able to process agricultural (fennel) and food production (liquid whey) waste. The pilot plant, using different thermal and filtration process parameters, is able to recover pectin and whey proteins in a single processing unit in order to produce edible films. An innovative feature of the proposed configuration is related to the possibility of coupling different types of waste treatment, obtaining a final product with a higher economical value, combining the two processing lines. Although an edible film production procedure based on pectin extracted from fennel matrix and whey proteins has already been published in literature, the scale-up process highlighted several critical issues, in particular related to the fennel matrix. Nonetheless, the pilot plant configuration allowed an edible film to be produced that is suitable for use as a direct coating to improve the shelf-life of food products.
Notes on the occurrence of Trypanosoma sp. (Kinetoplastida: Trypanosomatidae) in freshwater fishes from South Africa
Authors: Ferreira Maryke L. , Avenant-Oldewage Annemariè
Published: March 2013

A total of 257 fishes from four families, Clariidae, Cichlidae, Cyprinidae and Schilbeidae were collected from three localities: the Sand River Dam, Swaziland; the Nylsvlei Nature Reserve, South Africa and the Vaal Dam and Vaal River Barrage, South Africa. Only fishes (n= 154) from Clariidae and Cichlidae were found to be infected with trypanosomes. A total of 221 Clarias gariepinus (Burchell 1822) were collected from the Vaal Dam and Vaal Barrage area, South Africa. Of these, 74%(89/121) were infected with trypanosomes from the Vaal Dam and 63%(63/100) from the Vaal River Barrage, with no seasonal infection pattern. A prevalence of 25%(1/4) was found in C. gariepinus from the Sand River Dam, Swaziland, and a 50% (1/2) prevalence was found in Tilapia sparrmanii from the Nylsvlei Nature Reserve, South Africa. Standard measurements conformed closely to the morphometric and morphological descriptions of Trypanosoma mukasai. This article provides new locality records for T. mukasai from the Vaal Dam, Vaal River Barrage and Nylsvlei Nature Reserve (South Africa) and the Sand River Dam (Swaziland). Tilapia sparrmanii collected in the Sand River Dam in Swaziland is also noted as a new host record.
Two fast temperature sensors for probing of the Atmospheric Boundary Layer using small Remotely Piloted Aircraft (RPA)
Authors: Wildmann N. , Mauz M. , Bange J.
Published: March 2013

Abstract. Two types of temperature sensors are designed and tested, a thermocouple and a fine wire resistance thermometer. The intention of this study is to figure out which kind of measurement principle is in general more suited for atmospheric boundary layer meteorology with small RPA. The sensors are calibrated in a NIST traceable climate chamber and validated in flight against tower measurements, radiosondes and remote sensing. The sensors have a measurement range of at least −10...50° C, an absolute RMS error of less than ±0.2 K which is stable over the lifetime of the sensors, and a resolution of about 0.01 K. Both devices are tested for typical errors like radiation error and adiabatic heating, as well as for their dynamic response. Spectral resolutions of up to approximately 10 Hz can be obtained with both sensors, which makes them suitable for turbulence measurements. Their low cost of less than 100 EUR in pure hardware is a major advantage for research with small RPA.
Indications of nitrogen-limited methane uptake in tropical forest soils
Authors: Veldkamp E. , Koehler B. , Corre M. D.
Published: March 2013

Abstract. Tropical forest soils contribute 6.2 Tg yr−1 (28%) to global methane (CH4) uptake, which is large enough to alter CH4 accumulation in the atmosphere if significant changes would occur to this sink. Elevated deposition of inorganic nitrogen (N) to temperate forest ecosystems has been shown to reduce CH4 uptake in forest soils, but almost no information exists from tropical forest soils even though projections show that N deposition will increase substantially in tropical regions. Here we report the results from long-term, ecosystem-scale experiments in which we assessed the impact of chronic N addition on soil CH4 fluxes from two old-growth forests in Panama: (1) a lowland, moist (2.7 m yr−1 rainfall) forest on clayey Cambisol and Nitisol soils with controls and N-addition plots for 9–12 yr, and (2) a montane, wet (5.5 m yr−1 rainfall) forest on a sandy loam Andosol soil with controls and N-addition plots for 1–4 yr. We measured soil CH4 fluxes for 4 yr (2006–2009) in 4 replicate plots (40 m × 40 m each) per treatment using vented static chambers (4 chambers per plot). CH4 fluxes from the lowland control plots and the montane control plots did not differ from their respective N-addition plots. In the lowland forest, chronic N addition did not lead to inhibition of CH4 uptake; instead, a negative correlation of CH4 fluxes with nitrate (NO3−) concentrations in the mineral soil suggests that increased NO3− levels in N-addition plots had stimulated CH4 consumption and/or reduced CH4 production. In the montane forest, chronic N addition also showed negative correlation of CH4 fluxes with ammonium concentrations in the organic layer, which suggests that CH4 consumption was N limited. We propose the following reasons why such N-stimulated CH4 consumption did not lead to statistically significant CH4 uptake: (1) for the lowland forest, this was caused by limitation of CH4 diffusion from the atmosphere into the clayey soils, particularly during the wet season, as indicated by the strong positive correlations between CH4 fluxes and water-filled pore space (WFPS); (2) for the montane forest, this was caused by the high WFPS in the mineral soil throughout the year, which may not only limit CH4 diffusion from the atmosphere into the soil but also favour CH4 production; and (3) both forest soils showed large spatial and temporal variations of CH4 fluxes. We conclude that in these extremely different tropical forest ecosystems there were indications of N limitation on CH4 uptake. Based on these findings, it is unlikely that elevated N deposition on tropical forests will lead to widespread inhibition of CH4 uptake.
Radon decay products and 10–1100 nm aerosol particles in Postojna Cave
Authors: Bezek M. , Gregorič A. , Vaupotič J.
Published: March 2013

Abstract. At the lowest point along the tourist route in Postojna Cave, the activity concentration of radon (222Rn) decay products and the number concentration and size distribution of aerosol particles in the size range of 10–1100 nm were monitored, with the focus on the unattached fraction (fun) of radon decay products (RnDPs), a key parameter in radon dosimetry. The total number concentration of aerosols during visits in summer was lower (700 cm−3) than in winter (2800 cm−3), and was dominated by <50 nm particles (related to unattached RnDPs) in summer and by >50 nm particles (related to the attached RnDPs) in winter. This explains the higher fun values in summer (0.75) and the lower winter measurement (0.04) and, consequently, DCFD values of 43.6 and 13.1 mSv WLM−1 respectively for the calculated dose conversion factors. The difference is caused by an enhanced inflow of fresh outside air, driven in winter by the higher air temperature in the cave compared to outside, resulting in the introduction of outside aerosol particles into the cave.
Assessing institutional capacities to adapt to climate change – integrating psychological dimensions in the Adaptive Capacity Wheel
Authors: Grothmann T. , Grecksch K. , Winges M. , Siebenhüner B.
Published: March 2013

Abstract. Several case studies show that "soft social factors" (e.g. institutions, perceptions, social capital) strongly affect social capacities to adapt to climate change. Many soft social factors can probably be changed faster than "hard social factors" (e.g. economic and technological development) and are therefore particularly important for building social capacities. However, there are almost no methodologies for the systematic assessment of soft social factors. Gupta et al. (2010) have developed the Adaptive Capacity Wheel (ACW) for assessing the adaptive capacity of institutions. The ACW differentiates 22 criteria to assess six dimensions: variety, learning capacity, room for autonomous change, leadership, availability of resources, fair governance. To include important psychological factors we extended the ACW by two dimensions: "adaptation motivation" refers to actors' motivation to realise, support and/or promote adaptation to climate. "Adaptation belief" refers to actors' perceptions of realisability and effectiveness of adaptation measures. We applied the extended ACW to assess adaptive capacities of four sectors – water management, flood/coastal protection, civil protection and regional planning – in North Western Germany. The assessments of adaptation motivation and belief provided a clear added value. The results also revealed some methodological problems in applying the ACW (e.g. overlap of dimensions), for which we propose methodological solutions.
Traumatic Nasolacrimal Duct Obstruction: Clinical Profile, Management, and Outcome
Authors: Mukherjee Bipasha , Dhobekar Mangesh
Published: March 2013

Purpose

To review clinical profile, management, and outcome in cases of traumatic nasolacrimal duct obstruction (NLDO).

Methods

A retrospective analysis of 28 patients with the diagnosis of traumatic NLDO during a 12-year period was done. Data regarding nature and pattern of injury, associated damage, clinical features, investigations, management, outcome, and follow-up were reviewed.

Results

Of the 28 patients reviewed in the study, 19 (68%) were male and 9 (32%) were female. Mean age of the patients was 30.1 years. The most common cause of traumatic NLDO was high-velocity blunt injury encountered in road traffic accidents (70%), and the most common pattern of injury was naso-orbito-ethmoidal fractures (64%). Traumatic telecanthus was the most commonly associated periocular injury (54%). Twenty-one patients (75%) were investigated with computed tomography–dacryocystography. A total of 26 patients were treated with external dacryocystorhinostomy with (75%) or without (18%) silicon intubation and 2 (7%) patients underwent dacryocystectomy. General anesthesia was administered in 19 (68%) patients and local anesthesia in 9 (32%) patients. Mean follow-up period was 7.71 months (range 3 months to 6 years). Successful outcome was recorded in 25 out of 26 eyes (96%) operated with external dacryocystorhinostomy with or without silicone intubation.

Conclusions

Naso-orbito-ethmoidal fracture is the main cause of traumatic NLDO, commonly in young male individuals. Telecanthus is an important presenting feature. Computed tomography–dacryocystography is a useful imaging modality in preoperative assessment and surgical planning. External dacryocystorhinostomy with or without intubation under general anesthesia gives good surgical outcome.
Internet-based Perceptual Learning in Treating Amblyopia
Authors: Zhang Wenqiu , Yang Xubo , Liao Meng , Zhang Ning , Liu Longqian
Published: March 2013

Purpose

Amblyopia is a common childhood condition, which affects 2%–3% of the population. The efficacy of conventional treatment in amblyopia seems not to be high and recently perceptual learning has been used for treating amblyopia. The aim of this study was to address the efficacy of Internet-based perceptual learning in treating amblyopia.

Methods

A total of 530 eyes of 341 patients with amblyopia presenting to the outpatient department of West China Hospital of Sichuan University between February 2011 and December 2011 were reviewed. A retrospective cohort study was conducted to compare the efficacy of Internet-based perceptual learning and conventional treatment in amblyopia. The efficacy was evaluated by the change in visual acuity between pretreatment and posttreatment.

Results

The change in visual acuity between pretreatment and posttreatment by Internet-based perceptual learning was larger than that by conventional treatment in ametropic and strabismic amblyopia (p<0.05), but smaller than that in anisometropic and other types of amblyopia (p<0.05). The improvement in visual acuity by Internet-based perceptual learning was larger for patients with amblyopia not younger than 7 years (p<0.05). The mean cure time of patients with amblyopia by Internet-based perceptual learning was 3.06 ± 1.42 months, while conventional treatment required 3.52 ± 1.67 months to reach the same improvement (p<0.05).

Conclusions

Internet-based perceptual learning can be considered as an alternative to conventional treatment. It is especially suitable for ametropic and strabismic patients with amblyopia who are older than 7 years and can shorten the cure time of amblyopia.
The Hip Sports Activity Scale (HSAS) for Patients with Femoroacetabular Impingement
Authors: Naal Florian D. , Miozzari Hermes H. , Kelly Bryan T. , Magennis Erin M. , Leunig Michael , Noetzli Hubert P.
Published: March 2013

Purpose

To develop and validate a sports activity scale for patients with a diagnosis of femoroacetabular impingement (FAI).

Methods

A nine level Hip Sports Activity Scale (HSAS) was constructed both in German and English languages. Fifty-nine consecutive patients undergoing surgical treatment for FAI at two centers in Switzerland and in the US completed a questionnaire set consisting of the HSAS, the University of California at Los Angeles (UCLA) activity scale and different hip joint-specific and generic outcome tools. For reliability assessment, the HSAS was completed twice about nine days apart. Evidence of reliability, validity and responsiveness was investigated by classical psychometric analyses.

Results

Reliability was excellent for both the German and the English versions with intraclass correlation coefficients of 0.94 and 0.96, respectively. Evidence of convergent validity was supported by moderate to high correlations with the UCLA activity scale and with the joint-specific measures used. Evidence of divergent validity was supported by low correlations with the SF-12 Mental Component Scale and the WOMAC stiffness subscale. The standardised response mean was 0.69.

Conclusions

The HSAS is a reliable and valid tool to determine sports levels in patients suffering from FAI. Its use in future studies investigating outcomes in young patients with hip disease can be recommended.

Level of Evidence

Level III, Diagnostic Studies – An independent, masked comparison with an appropriate population of patients, but reference standard not applied to all study patients.
Survival After Anaphylaxis Induced by a Bumblebee Sting in a Dog
Authors: Thomas Emily , Mandell Deborah C. , Waddell Lori S.
Published: March 2013

A 3.5 yr old castrated male miniature schnauzer was referred with a history of collapse after a bee sting to the left hind limb. At the time of presentation, 14 hr after the sting, the dog was hypotensive, comatose, seizuring, and had a brief period of cardiac arrest. Over the following 48 hr, the dog developed azotemia, severely elevated liver enzyme levels, hypertension, hematochezia, hematemesis, and disseminated intravascular coagulation (DIC). The dog’s neurologic status improved slowly, but significant behavioral abnormalities remained. The dog was discharged after 7 days with ongoing polyuria, polydipsia, and behavioral changes. The polydipsia and polyuria resolved within a few days, but the behavioral changes continued for 6 wk. Reports of anaphylaxis from any cause are sparse in the veterinary literature. This is the first report of suspected anaphylaxis following a bee sting. There are no previous reports of behavioral changes after physical recovery from anaphylaxis.
Efficacy of Incisional Gastropexy for Prevention of GDV in Dogs
Authors: Benitez Marian E. , Schmiedt Chad W. , Radlinsky MaryAnn G. , Cornell Karen K.
Published: March 2013

Incisional gastropexy (IG) is routinely performed as either a prophylactic procedure to prevent occurrence of gastric dilatation-volvulus (GDV) or at the time of surgical correction of GDV to prevent recurrence. Despite its common use, the long-term efficacy of the IG procedure has not been reported. The hypothesis of this study was that IG performed either during surgical treatment of GDV or as a prophylactic measure would effectively prevent GDV. Medical records of 61 dogs undergoing IG following either gastric derotation for treatment of GDV or as a prophylactic procedure were evaluated retrospectively. Median follow-up time for all dogs was 717 days (range, 49–2,511 days). Of the 61 dogs, 27 had prophylactic IG performed. The remaining 34 dogs presented for GDV and had an IG performed during surgical treatment of GDV. No dog experienced GDV after IG. Recurrence of gastric dilatation (GD) alone was noted in 3 of 34 patients (8.8%) undergoing IG during surgery for GDV and in 3 of 27 patients (11.1%) treated prophylactically with IG. This study confirmed the efficacy of IG for the long-term prevention of GDV in dogs.
Accuracy of US-Guided FNA of Focal Liver Lesions in Dogs: 140 Cases (2005–2008)
Authors: Bahr Katherine L. , Sharkey Leslie C. , Murakami Tsuyoshi , Feeney Daniel A.
Published: March 2013

Medical records from dogs having abdominal ultrasound (US) performed between March 2005 and October 2008 were reviewed for detection of focal liver lesions (FLL) with both cytologic and histologic sampling. Samples were classified as to either the presence or absence of major categories of pathologic processes, including malignant neoplasia, inflammation, hyperplasia/benign neoplasia, vacuolar change, extramedullary hematopoeisis, cholestasis, necrosis, and no microscopic abnormalities. Evaluation of selection bias was performed by review of the relative distribution of cytologic diagnoses for cases with histology compared with cases excluded from the comparison analysis because histology results were not available. Cytology had the highest sensitivity for vacuolar change (57.9%), followed by neoplasia (52.0%). Cytology had the highest positive predictive value (PPV) for neoplasia (86.7%) followed by vacuolar change (51.6%). Cytology had lower sensitivity and PPVs for inflammation, necrosis, and hyperplasia. The ability of cytology to characterize disease in canine FLL varies by pathologic process. Clinicians can have a high degree of confidence when a cytologic diagnosis of neoplasia is given; however, cytology is less reliable for excluding the potential for neoplasia. Cytology has a low sensitivity and PPV for inflammation and a limited diagnostic performance for the diagnosis of vacuolar change.
Design of a Robot End-Effector Grabbing Mechanism Based on a Bionic Snake Mouth
Authors: Zhuang Fu , Hangfei Zhou , Zijuan Liu , Jian Fei , Weixin Yan , Yanzheng Zhao
Published: March 2013

Inspired by the bite and swallowing function of a snake's mouth, a robot end-effector grabbing mechanism was designed. The grabbing movement is realized by the ‘bite’ function of the bionic snake mouth actuator, and the ‘swallowing’ function insures a continuous grip on the object. To implement the continuous grip function of the new robot end-effector, the complex motion of a snake's mouth is simplified into three basic movements based on the anatomy of a snake's mouth and with a combination of bionics and engineering. The upper jaw consists of a double four-bar linkage mechanism and the lower jaw mechanism implementing a lateral expansion function are the two elements of the robot end-effector. The relationship model and the corresponding curves of the actuating force and gripping force are necessary to implement an open-loop control of the robot end-effector. Through analysis and simulation, linkage parameters are determined to implement the desired motion.
Learning Faster by Discovering and Exploiting Object Similarities
Authors: Janež Tadej , Žabkar Jure , Možina Martin , Bratko Ivan
Published: March 2013

In this paper we explore the question: “Is it possible to speed up the learning process of an autonomous agent by performing experiments in a more complex environment (i.e., an environment with a greater number of different objects)?” To this end, we use a simple robotic domain, where the robot has to learn a qualitative model predicting the change in the robot's distance to an object. To quantify the environment's complexity, we defined cardinal complexity as the number of objects in the robot's world, and behavioural complexity as the number of objects' distinct behaviours. We propose Error reduction merging (ERM), a new learning method that automatically discovers similarities in the structure of the agent's environment. ERM identifies different types of objects solely from the data measured and merges the observations of objects that behave in the same or similar way in order to speed up the agent's learning. We performed a series of experiments in worlds of increasing complexity. The results in our simple domain indicate that ERM was capable of discovering structural similarities in the data which indeed made the learning faster, clearly superior to conventional learning. This observed trend occurred with various machine learning algorithms used inside the ERM method.
Game Theory Models for Multi-Robot Patrolling of Infrastructures
Authors: Hernández Erik , del Cerro Jaime , Barrientos Antonio
Published: March 2013

This work is focused on the problem of performing multi-robot patrolling for infrastructure security applications in order to protect a known environment at critical facilities. Thus, given a set of robots and a set of points of interest, the patrolling task consists of constantly visiting these points at irregular time intervals for security purposes. Current existing solutions for these types of applications are predictable and inflexible. Moreover, most of the previous work has tackled the patrolling problem with centralized and deterministic solutions and only few efforts have been made to integrate dynamic methods. Therefore, one of the main contributions of this work is the development of new dynamic and decentralized collaborative approaches in order to solve the aforementioned problem by implementing learning models from Game Theory. The model selected in this work that includes belief-based and reinforcement models as special cases is called Experience-Weighted Attraction. The problem has been defined using concepts of Graph Theory to represent the environment in order to work with such Game Theory techniques. Finally, the proposed methods have been evaluated experimentally by using a patrolling simulator. The results obtained have been compared with previous available approaches.
Robust Unstructured Road Detection: The Importance of Contextual Information
Authors: Shang Erke , An Xiangjing , Li Jian , Ye Lei , He Hangen
Published: March 2013

Unstructured road detection is a key step in an unmanned guided vehicle (UGV) system for road following. However, current vision-based unstructured road detection algorithms are usually affected by continuously changing backgrounds, different road types (shape, colour), variable lighting conditions and weather conditions. Therefore, a confidence map of road distribution, one of contextual information cues, is theoretically analysed and experimentally generated to help detect unstructured roads. Two traditional algorithms, support vector machine (SVM) and k-nearest neighbour (KNN), are carried out to verify the helpfulness of the proposed confidence map. Following this, a novel algorithm, which combines SVM, KNN and the confidence map under a Bayesian framework, is proposed to improve the overall performance of the unstructured road detections. The proposed algorithm has been evaluated using different types of unstructured roads and the experimental results show its effectiveness.
An Architecture to Develop Multimodal Educative Applications with Chatbots
Authors: Griol David , Callejas Zoraida
Published: March 2013

Animated characters are beginning to be used as pedagogical tools, as they have the power to capture students' attention and foster their motivation for discovery and learning. However, in order for them to be widely employed and accepted as a learning resource, they must be easy to use and friendly. In this paper we present an architecture that facilitates building interactive pedagogical chatbots that can interact with students in natural language. Our proposal provides a modular and scalable framework to develop such systems efficiently. Additionally, we present Geranium, a system that helps children to appreciate and protect their environment with an interactive chatbot developed following our scheme.
Experimental Validation of a Dynamic Model for Lightweight Robots
Authors: Gasparetto Alessandro , Moosavi Amir Kiaeian , Boscariol Paolo , Giovagnoni Marco
Published: March 2013

Nowadays, one of the main topics in robotics research is dynamic performance improvement by means of a lightening of the overall system structure.

The effective motion and control of these lightweight robotic systems occurs with the use of suitable motion planning and control process. In order to do so, model-based approaches can be adopted by exploiting accurate dynamic models that take into account the inertial and elastic terms that are usually neglected in a heavy rigid link configuration.

In this paper, an effective method for modelling spatial lightweight industrial robots based on an Equivalent Rigid Link System approach is considered from an experimental validation perspective.

A dynamic simulator implementing the formulation is used and an experimental test-bench is set-up. Experimental tests are carried out with a benchmark L-shape mechanism.
The healthy vending machine
Authors: Preston James A.
Published: March 2013

A good problem can capture students' curiosity and can serve many functions in the elementary school classroom: to introduce specific concepts the teacher can build on once students recognize the need for additional mathematics or to help students see where to apply already-learned concepts. We encourage teachers to use the monthly problem in their own classrooms and report solutions, strategies, reflections, and misconceptions to the journal audience.
Challenge Beginning Teacher Beliefs
Authors: Lannin John K. , Chval Kathryn B.
Published: March 2013

Use these specific strategies to confront assumptions about teaching and learning mathematics.
The marriage of place and value
Authors: Hose Justin C. , Wells Tres
Published: March 2013

Students say some amazing things. Back Talk highlights the learning of one or two students and their approach to solving a math problem. Each article includes the prompt used to initiate the discussion, a portion of dialogue, student work samples (when applicable), and teacher insights into the mathematical thinking of students. This article investigates a student's understanding of the base-ten number system and how she uses her conceptions of place value to learn about the base-two number system.
An analysis of the implementation of PEPFAR's anti‐prostitution pledge and its implications for successful HIV prevention among organizations working with sex workers
Authors: Ditmore Melissa Hope , Allman Dan
Published: March 2013

Introduction

Since 2003, US government funding to address the HIV and AIDS pandemic has been subject to an anti‐prostitution clause. Simultaneously, the efficacy of some HIV prevention efforts for sex work in areas receiving US government funding has diminished. This article seeks to explain why.

Methods

This analysis utilizes a case story approach to build a narrative of defining features of organizations in receipt of funding from the President's Emergency Plan for AIDS Relief (PEPFAR) and other US funding sources. For this analysis, multiple cases were compiled within a single narrative. This helps show restrictions imposed by the anti‐prostitution clause, any lack of clarity of guidelines for implementation and ways some agencies, decision‐making personnel, and staff on the ground contend with these restrictions.

Results

Responses to PEPFAR's anti‐prostitution clause vary widely and have varied over time. Organizational responses have included ending services for sex workers, gradual phase‐out of services, cessation of seeking US government HIV funds and increasing isolation of sex workers. Guidance issued in 2010 did not clarify what was permitted. Implementation and enforcement has been dependent in part on the interpretations of this policy by individuals, including US government representatives and organizational staff.

Conclusions

Different interpretations of the anti‐prostitution clause have led to variations in programming, affecting the effectiveness of work with sex workers. The case story approach proved ideal for working with information like this that is highly sensitive and vulnerable to breach of anonymity because the method limits the potential to betray confidences and sources, and limits the potential to jeopardize funding and thereby jeopardize programming. This method enabled us to use specific examples without jeopardizing the organizations and individuals involved while demonstrating unintended consequences of PEPFAR's anti‐prostitution pledge in its provision of services to sex workers and clients.
Status of Logania imbricata (Guillaumin) Steenis & Leenh. (Loganiaceae)
Authors: Foster Charles S.P. , Conn Barry John
Published: March 2013

Molecular systematics has clarified the taxonomic status of Logania imbricata (Guillaumin) Steenis & Leenh. as being a species of the genus Geniostoma J.R.Forst. & G.Forst., with the new combination Geniostoma imbricatum (Guillaumin) C.S.P.Foster & B.J.Conn made here.
A new combination in Ackama (Cunoniaceae)
Authors: Heslewood Margaret M , Wilson Peter G
Published: March 2013

Taxonomic revisions of the genera Ackama and Caldcluvia have left one taxon without a current validly published name under the International Code of Nomenclature for algae, fungi and plants (ICN, McNeill et al. 2012), and the new combination Ackama paniculosa is made.