554 research outputs found

    Gaze-contingent flicker pupil perimetry detects scotomas in patients with cerebral visual impairments or glaucoma

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    The pupillary light reflex is weaker for stimuli presented inside as compared to outside absolute scotomas. Pupillograph perimetry could thus be an objective measure of impaired visual processing. However, the diagnostic accuracy in detecting scotomas has remained unclear. We quantitatively investigated the accuracy of a novel form of pupil perimetry. The new perimetry method, termed gaze-contingent flicker pupil perimetry, consists of the repetitive on, and off flickering of a bright disk (2 hz; 320 cd/m; 4° diameter) on a gray background (160 cd/m) for 4 seconds per stimulus location. The disk evokes continuous pupil oscillations at the same rate as its flicker frequency, and the oscillatory power of the pupil reflects visual sensitivity. We monocularly presented the disk at a total of 80 locations in the central visual field (max. 15°). The location of the flickering disk moved along with gaze to reduce confounds of eye movements (gaze-contingent paradigm). The test lasted ~5 min per eye and was performed on 7 patients with cerebral visual impairment (CVI), 8 patients with primary open angle glaucoma (age >45), and 14 healthy, age/gender-matched controls. For all patients, pupil oscillation power (FFT based response amplitude to flicker) was significantly weaker when the flickering disk was presented in the impaired as compared to the intact visual field (CVI: 12%, AUC = 0.73; glaucoma: 9%, AUC = 0.63). Differences in power values between impaired and intact visual fields of patients were larger than differences in power values at corresponding locations in the visual fields of the healthy control group (CVI: AUC = 0.95; glaucoma: AUC = 0.87). Pupil sensitivity maps highlighted large field scotomas and indicated the type of visual field defect (VFD) as initially diagnosed with standard automated perimetry (SAP) fairly accurately in CVI patients but less accurately in glaucoma patients. We provide the first quantitative and objective evidence of flicker pupil perimetry's potential in detecting CVI-and glaucoma-induced VFDs. Gaze-contingent flicker pupil perimetry is a useful form of objective perimetry and results suggest it can be used to assess large VFDs with young CVI patients whom are unable to perform SAP

    Resistance of sugarcane cultivars to Diataea saccharalis.

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    The objective of this work was to evaluate the ovipositions preference of Diatraea saccharalis and the effect of ten sugarcane cultivars on larval development. Oviposition preference was assessed under greenhouse condition by three releases of couples of moths, with subsequent counting of egg masses and eggs per plant. In order to evaluate the effet of the cultivars on larval development, each plant was infected with about 150 eggs, and, 29 days later, the total number of internodes, number of bored internodes, number of life forms found, larval and pupal weight and length, and the width of larval head capsule were evaluated.Título em português: Resistência de cultivares de cana?de?açúcar a Diatraea saccharalis

    Ten-year variations in population structure of pink-shrimp in a southwestern Atlantic Bay affected by highway construction

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    OBJETIVOS: A estrutura populacional de Farfantepenaeus brasiliensis e F. paulensis, consistindo principalmente de juvenis, foi avaliada durante a construção de uma via expressa ao longo de uma área de manguezais. Regiões estuarinas do sul do Brasil funcionam como locais de reprodução, berçários e de crescimento de uma variedade de organismos, incluindo duas das mais importantes espécies de camarões comerciais do Atlântico Sul Ocidental. Camarões foram coletados no Saco dos Limões, Baía Sul, Florianópolis, Estado de Santa Catarina, trimestralmente, de dia e de noite, entre 1997 e 2006. Flutuações em abundâncias de camarões podem estar relacionados aos seus ciclos de vida, com as maiores abundâncias no verão e primavera, ao invés de impactos promovidos pelas atividades de dragagem durante a construção da via expressa.OBJECTIVES: Population structures of Farfantepenaeus brasiliensis and F. paulensis, consisting mainly of juveniles, were evaluated during the construction of an expressway along a mangrove area. Estuarine regions in southern Brazil function as sites for reproduction, nursery and growth of a variety of organisms, including two of the most important species of shrimp for fisheries in the southwestern Atlantic. Shrimps were collected in Saco dos Limões creek, Baía-Sul, Florianópolis, State of Santa Catarina, four times a year, by day and night, between 1997 and 2006. Fluctuations in the abundances of shrimp appear to be related to their life cycles, with largest abundances in Summer and Spring, rather than to impacts promoted by dredging activities during the expressway construction

    Hidden lesions: a case of burnt remains.

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    One of the many challenging cases that forensic pathologists, anthropologists, and forensic imaging experts have to face are burnt human remains. Perpetrators frequently attempt to hide/destroy evidence and make the body unidentifiable by exposing it to fire. We present a case of a partially burnt body found in an apartment after an explosion. First, multidetector computed tomography (MDCT) images and the following autopsy revealed several lesions on the cranium. Forensic anthropologists were involved in order to specify the aetiology of the lesions observed on the cranium. Through an interdisciplinary approach bringing together MDCT scans, 3D surface scans, and anthropological analysis, it was possible to answer the questions raised during the autopsy. Analyses demonstrated that there were signs of blunt force trauma on the cranium vault that the perpetrator likely attempted to hide by exposing the body to fire. This case demonstrates the importance of close collaboration between forensic anthropologists, imaging experts, and forensic pathologists. This multidisciplinary approach allows for a better, more complete reconstitution of forensic cases. The analyses of burnt human remains are one of the many challenging tasks that forensic pathologists and anthropologists have to face.We present an occurrence of a partially burnt body after an explosion and forensic anthropologists were asked whether the nature of the lesions observed on the cranium could be further specified.Anthropological analyses of the skull were consistent with the radiological and autopsy report. It was possible to reconstruct the various lesions on the dry bone.The case demonstrates the importance of an interdisciplinary approach and the close collaboration between forensic anthropologists, imaging experts, and forensic pathologists

    Vortex pinning in Au-irradiated FeSe0.4Te0.6 crystals from the static limit to gigahertz frequencies

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    Fe(Se,Te) is one of the simplest compounds of iron-based superconductors, but it shows a variety of vortex pinning phenomena both in thin-film and single-crystal forms. These properties are particularly important in light of its potential for applications ranging from the development of coated conductors for high-field magnets to topological quantum computation exploiting the Majorana particles found in the superconducting vortex cores. In this paper, we characterize the pinning properties of FeSe 0.4 Te 0.6 single crystals, both pristine and Au-irradiated, with a set of characterization techniques ranging from the static limit to the GHz frequency range by using dc magnetometry, ac susceptibility measurements of both the fundamental and the third harmonic signals, and by microwave coplanar waveguide resonator measurements of London and Campbell penetration depths. We observed signatures of single vortex pinning that can be modeled by a parabolic pinning potential, dissipation caused by flux creep, and a general enhancement of the critical current density after 320 MeV Au ion irradiation

    Carcass Quality of Slaughtered Cika and Brown Cattle in Slovenia

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    The aim of the study was to compare carcass traits between Cika and Brown cattle of all slaughter categories. The data used were collected in Slovenian slaughterhouses from 2007 to 2010. After the slaughter carcass weight was recorded and carcass conformation and fatness were scored according to the EUROP system. Net daily gain was calculated. Data were analysed by GLM procedure of statistical package SAS/ STAT considering breed, month of the slaughter and year of the slaughter nested within the breed as fixed effects. Cika bulls (under 24 months old) were two months younger at slaughter (20.2 months) and achieved lower carcass weight (266.7 kg) compared to Brown bulls (22.4 months, 330.0 kg). Also in all other categories except in calves under eight months old, Brown cattle had higher carcass weight. Bulls under 24 months old, steers, cows and calves over eight to 12 months old of Brown cattle were older at slaughter compared to Cika breed. Net daily gain was also higher in all slaughtered categories of Brown cattle. Even if the slaughtered Brown cattle had heavier carcass weight compared to Cika cattle there was almost no significant difference in carcass conformation. Carcasses of Cika bulls under 24 months old had conformation 6.4 while Brown bulls 6.3. Likewise carcasses of Cika calves over eight to 12 months had higher conformation score (5.7) than Brown (4.8) calves. Fatness was higher in Brown bulls, steers and heifers compared to Cika cattle, while Cika cows had higher fatness than Brown cows

    Cobalt-Based Metallic Glass Microfibers for Flexible Electromagnetic Shielding and Soft Magnetic Properties

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    Thin and flexible materials that can provide efficient electromagnetic interference (EMI) shielding are urgently needed, particularly those that can be rapidly processed and withstand harsh environments. Cobalt-based metallic glasses stand out as prime candidates due to their excellent soft magnetic properties, satisfactory shielding features, and mechanical properties. Herein, a recently developed technique is used to fabricate metallic glass microfibers from Co66Fe4Mo2Si16B12 alloy. The produced microfibers are characterized for their size and uniformity by scanning electron microscopy and their amorphous structure is confirmed by X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The cobalt-based metallic glass microfibers show an EMI shielding factor that reaches five in the static regime and obtains an up to 25-fold increase of the attenuation constant in the Ku frequency band. This performance originates from the combination of soft magnetic properties and excellent electrical conductivity. In addition, the flexible microfibers exhibit excellent hardness and elasticity making them suitable for EMI shielding of complex geometries. Their hardness and elastic modulus are measured by nanoindentation to be 11.31 +/- 0.60 GPa, and 110.54 +/- 11.24 GPa, respectively.A novel method is used to fabricate flexible Co66Fe4Mo2Si16B12 metallic-glass microfibers for electronics, boasting a hardness of 11.31 +/- 0.60 GPa and an elastic modulus of 110.54 +/- 11.24 GPa. Their EMI shielding exhibits clear anisotropy with a factor of 5 and up to 25-fold increased attenuation in the Ku band. These properties position them well for EMI shielding in intricate geometries.imag

    Bid in plants: characterization of plants expressing the animal pro-apoptotic protein Bid

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    Programmed cell death (PCD) is a crucial process in all the living organisms. Similarities and substantial differences are present in control, signaling and execution of this program in plants and animals. The major regulators of the commitment to PCD in animal cells are the BCL-2 protein family. Homologous proteins are absent in plants. Among these, the BH3-only protein Bid is crucial for both life and death of the animal cells. We have constitutively expressed this pro-apoptotic protein, Bid from mouse, in Arabidopsis thaliana and in Nicotiana tabacum to explore the possible cross-talk between the apoptotic signaling pathway and the plant PCD pathway. This protein has been inserted in its full-length form, flBid, and not in its caspase-processed active form, tBid. For this reason, it requires an activation signal to exert its action on mitochondria that can be either a caspase-like processing activity or the binding of specific signal molecules (i.e. lysolipid molecules). Transgenic plants show no differences with wild-type in growth and development. They were treated with different abiotic stress conditions to activate the PCD signaling cascade and to study the possible involvement of responses able to induce flBid activation within plant cells. No significant differences were observed when Bid plants and WT plants were treated either with NO or H2O2 as PCD inducer. Small differences are observed in necrotic death induction: Bid plants leaves appear to be more sensitive to oxidative stress when compared to the wild-type ones. Caspase-like activity on Bid protein is absent in these conditions. In root hair cells, we have observed a reduction in the number of apoptotic cells due to an increase of the necrotic ones after 24 hours from H2O2 treatment. These results indicated that full length Bid do not significantly change PCD response to H2O2 and NO stress in plants
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