1,904 research outputs found

    The short and long of it: neural correlates of temporal-order memory for autobiographical events

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    Previous functional neuroimaging studies of temporal-order memory have investigated memory for laboratory stimuli that are causally unrelated and poor in sensory detail. In contrast, the present functional magnetic resonance imaging (fMRI) study investigated temporal-order memory for autobiographical events that were causally interconnected and rich in sensory detail. Participants took photographs at many campus locations over a period of several hours, and the following day they were scanned while making temporal-order judgments to pairs of photographs from different locations. By manipulating the temporal lag between the two locations in each trial, we compared the neural correlates associated with reconstruction processes, which we hypothesized depended on recollection and contribute mainly to short lags, and distance processes, which we hypothesized to depend on familiarity and contribute mainly to longer lags. Consistent with our hypotheses, parametric fMRI analyses linked shorter lags to activations in regions previously associated with recollection (left prefrontal, parahippocampal, precuneus, and visual cortices), and longer lags with regions previously associated with familiarity (right prefrontal cortex). The hemispheric asymmetry in prefrontal cortex activity fits very well with evidence and theories regarding the contributions of the left versus right prefrontal cortex to memory (recollection vs. familiarity processes) and cognition (systematic vs. heuristic processes). In sum, using a novel photo-paradigm, this study provided the first evidence regarding the neural correlates of temporal-order for autobiographical events

    Watching My Mind Unfold versus Yours: An fMRI Study Using a Novel Camera Technology to Examine Neural Differences in Self-projection of Self versus Other Perspectives

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    Self-projection, the capacity to re-experience the personal past and to mentally infer another person's perspective, has been linked to medial prefrontal cortex (mPFC). In particular, ventral mPFC is associated with inferences about one's own self, whereas dorsal mPFC is associated with inferences about another individual. In the present fMRI study, we examined self-projection using a novel camera technology, which employs a sensor and timer to automatically take hundreds of photographs when worn, in order to create dynamic visuospatial cues taken from a first-person perspective. This allowed us to ask participants to self-project into the personal past or into the life of another person. We predicted that self-projection to the personal past would elicit greater activity in ventral mPFC, whereas self-projection of another perspective would rely on dorsal mPFC. There were three main findings supporting this prediction. First, we found that self-projection to the personal past recruited greater ventral mPFC, whereas observing another person's perspective recruited dorsal mPFC. Second, activity in ventral versus dorsal mPFC was sensitive to parametric modulation on each trial by the ability to relive the personal past or to understand another's perspective, respectively. Third, task-related functional connectivity analysis revealed that ventral mPFC contributed to the medial temporal lobe network linked to memory processes, whereas dorsal mPFC contributed to the fronto-parietal network linked to controlled processes. In sum, these results suggest that ventral–dorsal subregions of the anterior midline are functionally dissociable and may differentially contribute to self-projection of self versus other

    Can the study of self-assembly in solution lead to a good model for the nucleation pathway? The case of tolfenamic acid

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    To further our understanding of the role of solution chemistry in directing nucleation processes new experimental and computational data are presented on the solution and crystallisation chemistry of tolfenamic acid (TA), a benchmark polymorphic compound. With these, and previously published data, we were able to establish that TA is rapidly fluctuating between conformers in solution with either solvated monomers or dimers present depending on the solvent. Hence, despite the fact that conformational polymorphs can be obtained from crystallisations in ethanol, we found no links between solution chemistry and crystallisation outcomes. We discuss the implications of these conclusions for the nature of the nucleation pathway via dimers and clusters and raise experimental questions about how best to undertake relevant crystallisation studies

    NIRS potential use for the determination of natural resources quality from dehesa (acorn and grass) in Montanera system for Iberian pigs.

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    NIRS technology has been used as an alternative to conventional methods to determinate the content of nutrients of acorns and grass from dehesa ecosystem. Dry matter (DM), crude fat (CF), crude protein (CP), starch, total phenolic compounds (TP), α-tocopherol, γ-tocopherol, fatty acids, neutral detergent fiber (NDF), total antioxidant activity (TAA) and total energy (TE) were determined by conventional methods for later development of NIRS predictive equations. The NIR spectrum of each sample was collected and for all studied parameters, a predictive model was obtained and external validated. Good prediction equations were obtained for moisture, crude fat, crude protein, total energy and γ-tocopherol in acorns samples, with high coefficients of correlation (1-VR) and low standard error of prediction (SEP) (1-VR=0.81, SEP=2.62; 1-VR=0.92, SEP=0.54; 1-VR=0.86, SEP=0.47; 1-VR=0.84, SEP=0.2; 1-VR=0.88, SEP=5.4, respectively) and crude protein, NDF, α-tocopherol and linolenic acid content in grass samples (1-VR=0.9, SEP=1.99; 1-VR=0.87, SEP=4.13; 1-VR=0.76, SEP=10.9; 1-VR=0.82, SEP=0.6, respectively). Therefore, these prediction models could be used to determinate the nutritional composition of Montanera natural resources

    Neutronographic Residual Stress Analysis for Materials With Depth Gradients of the Strain Free Lattice Parameter d0{{{d}}}_{0} for the Example of a Case-Hardened Steel 20MnCr5

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    In the present work, ring-shaped samples made from steel 20MnCr5 were low-pressure carburized (LPC) and subsequently hardened by gas quenching (case-hardened). This results in a near-surface gradient in chemical composition, microstructure- and hardness distribution, as well as a three-dimensional residual stress (RS) distribution, which was investigated by neutron diffraction. Near-surface RSs in the ferrite-/martensite- and austenite phase are additionally determined by X-ray diffraction. It is shown that the chemical gradient has an influence on the chosen d0{{{d}}}_{0} strategy and how such a reference sample should be extracted. If near-surface RS values are to be determined by neutron diffraction, the pseudo-strain effect must be taken into account. For this purpose, a suitable approach using the ‘‘open source’’ software SIMRES and STRESSFIT is also presented. By combining neutron and X-ray diffraction data, a complete RS distribution over the whole sample can be obtained

    A framework for integrating sustainability estimation with concepts of rules of building measurement

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    BIM promises improvement in project delivery efficiencies such as reduction in costs and errors and timely completion. Benefits are also expected in sustainable construction aspect with research efforts being extended to sustainable design and assessment. These efforts are still been explored for the purposes of unifying quantification methodologies, the standardisation of system boundaries, terms of references and sustainability measures. Embodied energy and CO2 are two common measures that have been widely used in the construction sector. Although a number calculation system exists, they are not useful to the iterations that occur at the early stages of the project life cycle. At the procurement stage, professionals often rely on schedules and bill of quantities with no reference to sustainability credentials. It is therefore important to integrate sustainability measure with concepts in standard measurement methods. As such, we propose a framework to integrate sustainability credential with the concepts in rule of building measurement. We conclude that this framework can be applicable to any rule of building measurement and it is implementable in a computer programmable environment

    Bats as potential suppressors of multiple agricultural pests : A case study from Madagascar

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    The conversion of natural habitats to agriculture is one of the main drivers of biotic change. Madagascar is no exception and land-use change, mostly driven by slash-and-burn agriculture, is impacting the island's exceptional biodiversity. Although most species are negatively affected by agricultural expansion, some, such as synanthropic bats, are capable of exploring newly available resources and benefit from man-made agricultural ecosystems. As bats are known predators of agricultural pests it seems possible that Malagasy bats may be preferentially foraging within agricultural areas and therefore provide important pest suppression services. To investigate the potential role of bats as pest suppressors, we conducted acoustic surveys of insectivorous bats in and around Ranomafana National Park, Madagascar, during November and December 2015. We surveyed five landcover types: irrigated rice, hillside rice, secondary vegetation, forest fragment and continuous forest. 9569 bat passes from a regional assemblage of 19 species were recorded. In parallel, we collected faeces from the six most common bat species to detect insect pest species in their diet using DNA metabarcoding. Total bat activity was higher over rice fields when compared to forest and bats belonging to the open space and edge space sonotypes were the most benefited by the conversion of forest to hillside and irrigated rice. Two economically important rice pests were detected in the faecal samples collected - the paddy swarming armyworm Spodoptera mauritia was detected in Mops leucogaster samples while the grass webworm Herpetogramma licarsisalis was detected from Mormopterus jugularis and Miniopterus majori samples. Other crops pests detected included the sugarcane cicada Yanga guttulata, the macadamia nut-borer Thaumatotibia batrachopa and the sober tabby Ericeia inangulata (a pest of citrus fruits). Samples from all bat species also contained reads from important insect disease vectors. In light of our results we argue that Malagasy insectivorous bats have the potential to suppress agricultural pests. It is important to retain and maximise Malagasy bat populations as they may contribute to higher agricultural yields and promote sustainable livelihoods.Peer reviewe

    Proizvodnja pektinaza, aktivnih pri niskim temperaturama, pomoću psihrotolerantnih mikroorganizama

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    In winemaking, low temperatures are favourable for the production and retention of flavour and colour components, requiring the use of cold-active enzymes. For this reason, \u27psychrotolerant\u27 microorganisms have been isolated and selected based on their ability to produce pectinolytic enzymes with satisfactory activity at low temperatures. Different mature grape varieties with designation of origin were sampled from the region of San Rafael (Mendoza, Argentina), and pectinolytic bacterial, fungal and yeast strains were isolated. The pectinolytic activity was measured by cup-plate assay, quantification of released reducing sugars and viscosity reduction of pectin solution. Two bacteria (Bacillus sp. SC-G and SC-H) and two yeast strains were selected for their good pectinase activity at low temperatures. Among them, the strain with the highest activity, Bacillus sp. SC-H, was selected. According to their 16S rRNA profiles, Bacillus sp. SC-G and SC-H can be classified as members of Bacillus subtilis. Among the assayed techniques, the rotary evaporation was found to be the most appropriate to obtain enzymatic extracts with highest activity. The optimal conditions for the enzymatic activity were 30 °C and pH=5.0 for the concentrated extract, and 45 °C and pH=6.0 for the filtered supernatant. The concentrated extract presented good activity at 3 °C, confirming that it was a cold-active enzyme. Natural extraction and enzymatic preparation were used to extract pigments and polyphenols from Malbec grapes. Better results were obtained for the enzymatic extract with regard to index, shade, CIELab coordinates, CIELab colour differences and polyphenols (measured using Folin-Ciocalteu).Da bi se dobili što boji okus i boja vina, u vinarstvu se primjenjuju enzimi aktivni pri niskim temperaturama. Izolirani su psihrotolerantni mikroorganizmi sposobni da sintetiziraju pektinolitičke enzime aktivne pri niskim temperaturama. Zrelo grožđe različitih sorata s oznakom podrijetla prikupljeno je s područja San Rafael (Mendoz, Argentina), pa su izolirani pektinolitički sojevi bakterija, kvasaca i plijesni. Njihova je učinkovitost ispitana utvrđivanjem aktivnosti pektinaze na agaru (tzv. „cup-plate assay“), određivanjem udjela reducirajućih šećera što nastaju djelovanjem enzima i praćenjem smanjenja viskoznosti otopine pektina. Odabrana su dva soja bakterija (Bacillus sp. SC-G i SC-H) i dva soja kvasaca što luče pektinaze aktivne pri niskim temperaturama. Najveću aktivnost imao je soj Bacillus sp. SC-H. Određivanjem profila 16S rRNA utvrđeno je da su obje bakterije sojevi Bacillus subtilis. Najučinkovitiji enzimski ekstrakti dobiveni su u rotacijskom isparivaču. Optimalni uvjeti za aktivnost enzima bili su: 30 ºC i pH=5,0 za koncentrirani ekstrakt, te 45 ºC i pH=6,0 za filtrirani supernatant. Koncentrirani je ekstrakt imao dobru aktivnost i pri 3 °C, što potvrđuje njegovu učinkovitost pri niskim temperaturama. Prirodnom i enzimskom ekstrakcijom iz grožđa sorte Malbec izdvojeni su pigmenti i polifenoli. Enzimska je ekstrakcija bila učinkovitija, što potvrđuju indeks boje, CIELab koordinate, razlika boje prema CIELab sustavu i udjel polifenola određen Folin-Ciocalteu metodom

    Independence in CLP Languages

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    Studying independence of goals has proven very useful in the context of logic programming. In particular, it has provided a formal basis for powerful automatic parallelization tools, since independence ensures that two goals may be evaluated in parallel while preserving correctness and eciency. We extend the concept of independence to constraint logic programs (CLP) and prove that it also ensures the correctness and eciency of the parallel evaluation of independent goals. Independence for CLP languages is more complex than for logic programming as search space preservation is necessary but no longer sucient for ensuring correctness and eciency. Two additional issues arise. The rst is that the cost of constraint solving may depend upon the order constraints are encountered. The second is the need to handle dynamic scheduling. We clarify these issues by proposing various types of search independence and constraint solver independence, and show how they can be combined to allow dierent optimizations, from parallelism to intelligent backtracking. Sucient conditions for independence which can be evaluated \a priori" at run-time are also proposed. Our study also yields new insights into independence in logic programming languages. In particular, we show that search space preservation is not only a sucient but also a necessary condition for ensuring correctness and eciency of parallel execution

    Progressive multifocal leukoencephalopathy following fludarabine treatment in a chronic lymphocytic leukemia patient

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    Progressive multifocal leukoencephalopathy (PML) is a neurological disease caused by infection of the central nervous system (CNS) with the JC polyomavirus (JCV). JCV is endemic and infects a large proportion (70–90%) of healthy individuals worldwide, but infection is latent. JCV reactivation may occur, if the immune function is compromised. Aim: To present a PML case in a CLL patient after a long course of disease and treatment with fludarabine. JCV virus infection in this patient was proven both in brain biopsy material and blood. Methods: Patient with a nine-year history of CLL was hospitalized with the weakness in the right leg and left hand, tremors, speech difficulties. An MRI diagnosed infiltrative glial tumor of the left hemisphere, proliferating predominantly in the frontal lobe, more in the gyrus frontalis superior region. CNS tumor biopsy performed. Results: Morphology and immunoprofile of the lesion consistent with progressive multifocal leukoencephalopathy. The material from biopsy was diagnosed as positive for JCV DNA. JCV and HHV-7 genomic sequences were found in patient’s PBL DNA sample. In a plasma DNA sample, only genomic sequences were detected. Conclusion: The present case draws attention to the fact that the use of fludarabine and its combinations in CLL therapy increases the risk of JCV infection reactivation and development of serious complications like PML
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