The dimensions of the phantoms were based on measurements made on

The dimensions of the phantoms were based on measurements made on healthy adult rats and mice in our laboratory. For both phantoms, an elongated hollow cylinder with a round end was manufactured. The mould consisted of an outer cylinder (a test tube) within which was centrally placed a Perspex rod. For the rat phantom, the outer diameter and wall thickness were nominally 10 mm and 2 mm, respectively, and for the mouse phantom, they were 5 mm and 1.5 mm, respectively. The central rod was raised above the bottom of the outer tube by an amount equal to the required wall thickness. A 15% MAPK inhibitor concentration of PVA (PVA Gels, Kingston, NY, USA) in water

was used. The PVA gel was heated to 80°C–95°C in a water bath, drawn into a 10-ml syringe and then injected into the mould to a depth of 2 cm for the rat phantom and 8 mm for the mouse phantom. The gel was allowed to settle overnight to allow any air bubbles to dissipate. The moulds were

subject to two, four or six freeze–thaw cycles. Each cycle consisted of cooling at 0.5°C per minute to − 20°C, maintaining the temperature for 8 h and then allowing a rise to room temperature (22°C) at a rate selleck compound of 0.5°C/min. The mould was maintained at room temperature for at least 8 h prior to separation of the PVA from the mould. The finished phantoms were stored in deionized water to prevent dehydration. Relaxation time constants T1 and T2 have been reported for PVA at field strengths between 1 T and 3 T [16], [17] and [21], but there are no reported values taken at higher magnetic field strengths. Phantoms

were moulded from Ibrutinib mouse PVA; subjected to two, four and six freeze–thaw cycles; and then imaged in a 7-T MRI scanner [Agilent Technologies (formerly Varian, Inc.), Santa Clara, CA, USA]. Values of T1 were measured in the “short-axis” view using a fast spin echo sequence with inversion preparation and inversion times TI ranging from 10 ms to 3000 ms. The resulting image intensities were fitted to an exponential recovery curve using software on the scanner. Values of T2 were measured using fast spin echo sequences with echo times TE ranging from 10 ms to 60 ms, and the image intensities were fitted to an exponential decay curve using scanner software. The cardiac phantoms were mounted as shown in Fig. 1 within a sealed unit that could be filled with water and including an overflow as a precautionary measure in case of leakage during MRI scanning. The phantom was connected via stiff ¼-in. PTFE tubing (Cole-Parmer, Vernon Hills, IL, USA) to a gear pump (Michael Smith Engineering, Woking, UK). The phantom, tubing and gear pump were primed with water. The pump flow rate was controlled using a waveform generator. An offset sinusoidal waveform was applied in order to generate sinusoidal flow and hence cyclic distension of the phantom. Pumping frequencies up to 5 Hz [i.e., 300 beats per min (bpm)] were used for the rat phantom and up to 8 Hz (480 bpm) for the mouse phantom.

Nevertheless, tiered testing strategies for assessing metabolism

Nevertheless, tiered testing strategies for assessing metabolism have been suggested and reviewed previously ( ECVAM, 2002 and Coecke et al., 2005a). Models used to identify ADME properties (as well as organ-specific toxicities of chemicals) are summarised in Table 1, together with information regarding recommendations by the regulatory authorities and validation status. There is also a number of Quantitative Structure Activity Relationship (QSAR) models that

are available to both industry and academia and these include but are not limited to the OECD toolbox ( Table 2). Supporting GDC-0449 supplier activities from industry, European Commission and Academia to enable the development of non-animal models are summarised in Table 3. An EPAA workshop was held in Duesseldorf Everolimus on 24th/25th November, 2008, and was attended by scientific experts in the pharmaceutical, chemical, pesticide and cosmetic industries,

by regulators, as well as by academia. Participants included representatives of the Scientific Committee on Consumer Safety (SCCS), European Centre for the Validation of Alternative Methods (ECVAM), European Food Safety Authority (EFSA) and Directorate General (DG) for Research. The aim of the workshop was to discuss how to implement in vitro ADME test systems as part of Integrated Testing Strategies (ITS) for the testing of cosmetics, pharmaceuticals and industrial chemicals and pesticides (including agro-chemicals such as herbicides, fungicides, or insecticides). The present report presents the outcome of the break-out group discussions in describing how in vitro assays may be used within different industry sectors

and how regulators view in vitro data. It also outlines international projects aimed at developing alternative test models. In addition, Tyrosine-protein kinase BLK the break-out sessions discussed the suitability of in vitro approaches to systemic toxicity and hazard identification for target organs and steps required to attain regulatory acceptance. Emphasis is placed on in vitro assays and their use in risk assessment issues including preliminary risk assessment such as for prioritisation and deprioritisation, rather than in targeted risk assessment per se, since this is markedly different between industry sectors and is out of the scope of this paper. The use of animal assays is different across industries, whereby in vivo studies are required in one sector but banned in another. An overview of these differences and the agencies which affect the use of animals is described below. The European Medicines Agency (also known as the EMA) is a European agency which evaluates pharmaceuticals. In the USA, the equivalent agency is the Food and Drug Administration (FDA).

In conclusion, the present study suggested that curcumin post-tre

In conclusion, the present study suggested that curcumin post-treatment

augments B(a)P-induced apoptosis, and this eventually resulted in increased loss of adducts containing cells in mice evaluated at 24-120 h, suggesting the role of apoptosis in removal of adduct containing cells. Curcumin-mediated enhanced loss in BPDE-DNA adduct containing cells probably results Enzalutamide ic50 in reduction in the numbers of initiated cells in respective tissues, and this, along with curcumin-mediated inhibition of cell proliferation in these tissues leads to decrease in tumor multiplicity/tumor area/volume. The authors thank ACTREC for financial support, ACTREC and Council of Scientific and Industrial Research for awarding fellowship to Gaurav Kumar. The authors thank Dr. Mary Carter, Coordinator, Health Sciences Writing Centre, University of Oklahoma for her critical reading of the manuscript and Mrs. Sadhana Kannan for assisting in statistical analysis. The authors also thank Mr. Prasad Phase selleck and Mr. M. L. Jagtap for technical assistance “
“Lectins

include a group of proteins from non-immune origin that share the property of binding specifically and reversibly to carbohydrates [1]. Many plant lectins have attracted the attention due to their effects on proliferation and differentiation of animal cells, including lymphocytes and cancer cells. The in vitro and the in vivo antitumor effects of plant lectins are apparently associated with their ability to modulate growth, differentiation, proliferation and apoptosis ( [2], [3] and [4]). Toxicity of lectins must be considered before used as medical tools, mainly because they are considered antinutritional factors. It has been shown that binding lectins to intestinal epithelium can interfere others with nutrient absorption, reduction of

nitrogen retention, increased urine nitrogen excretion and reduction of insulin production in rats ([5], [6], [7] and [8]). Antinutritional and negative effects on digestion and absorption have been described for lectins from different sources ([9], [10], [11] and [12]). Studies with common bean (Phaseolus vulgaris L) lectins show that they can interfere with bowel function, causing changes in systemic metabolism and affecting the growth in rats, decrease in glucose, lipids, vitamin B12 and nitrogen uptake ( [13] and [14]). Adverse effects in organs are produced by some diet lectins, which included Phaseolus vulgaris. Rats fed with navy beans showed morphological changes that include increased weight of kidney and heart, pancreatic acinar atrophy, fatty liver and multiple histological lesions as thymus atrophy respect to control healthy rats.

Thus, the combination of both assays is necessary for a better ch

Thus, the combination of both assays is necessary for a better characterization of the antioxidant activity of a given sample. On the other hand, ATR presented a pro-oxidant capacity in a lipid-rich system, enhancing TBARS formation induced by AAPH incubation. In assays to evaluate the antioxidant potential against NO and H2O2, ATR also demonstrated to enhance the production of such species, acting as a pro-oxidant molecule. Nonetheless, ATR increased Selleckchem Stem Cell Compound Library NO production only at the higher concentration

tested, while other concentrations demonstrated to be innocuous. On the other hand, concentrations as low as 0.01 μg/ml were able to increase H2O2 production in vitro. We also observed that ATR presented no activity towards hydroxyl radical production or scavenging. NO exerts important physiological effects, such as vasoconstriction regulation and modulation of pro-inflammatory processes (Mollace et al., 2005, Salvemini et al., 2006 and Salvemini et al., 1996). In elevated concentrations, NO may interact with superoxide radicals to generate the

strong oxidizing agent peroxynitrite (ONOO−). Peroxynitrite diffuses through membranes and interacts with methionine side chains in proteins, sulphydryl groups, aromatic rings from tyrosine and guanine and generates nitrogen dioxide, which is an initiator of lipoperoxidation (Halliwell and Gutteridge, 2007). Thus, it is generally believed that an increase in superoxide radical formation both destroys the biological action of NO by promoting its removal ATM inhibitor and intensifies the formation of peroxynitrite (Salvemini et al., 2006). We observed here that ATR can act as a superoxide scavenger, and thus limit the action of this reactive species. Besides, it is postulated that during acute and chronic inflammation, superoxide production is enhanced to levels above the cleaning capacity of endogenous SOD enzymes, resulting in endothelial cell damage and increased microvascular permeability, up-regulation Vorinostat datasheet of adhesion molecules such as ICAM-1 (intercellular adhesion molecule 1) and P-selectin (through mechanisms not yet defined) that

recruit neutrophils to sites of inflammation, autocatalytic destruction of neurotransmitters and hormones such as noradrenaline and adrenaline, lipid peroxidation and oxidation, DNA damage and activation of PARP [poly(ADP-ribose) polymerase] (Salvemini et al., 2006). Superoxide removal by endogenous SOD and ATR would avoid such effects and also allow endogenous and ATR-induced NO to promote the activation of cycloxygenase and subsequent release of beneficial prostaglandins (Mollace et al., 2005 and Salvemini et al., 2006). The potential of ATR as an antiinflammatory and antinociceptive agent has been investigated based on reports of the utilization of lichen preparations for this purpose (Bugni et al., 2009).

9%, which was significantly lower than those of the pretreated em

9%, which was significantly lower than those of the pretreated embryos. The fetus development rate was 73.0% for the fresh embryos (control), and 57.7%, 65.2%, and 59.5% for those pretreated for 120, 300, and 600 s, respectively (Table 4). The implantation rate and fetus development rate were not significantly different between these groups. The implantation rate and fetus development rate in the group without pretreatment, however, were both 0%. The CPS used for vitrification must prevent damage due to ice crystal formation and growth, osmotic damage, and damage due to freeze fractures after the cytotoxicity of the cryoprotectant is suppressed [9]. P10 was expected to inhibit intracellular

ice crystal formation and growth. If the cryoprotectant permeates the embryo too slowly, however, the amount of cryoprotectant required selleck chemical to prevent ice crystal formation and growth may not enter the cells. It is also assumed find more that water rapidly penetrates from outside of the cells immediately after warming, before diffusion of intracellular cryoprotectant can occur, and the cells may be damaged due to osmotic expansion [15]. Moreover, if the time that the embryo is exposed to the pretreatment solution is too long, then cytotoxicity can occur [14]. In the experiments to develop the pretreatment solution for rat two-cell stage embryos, propylene glycol was selected because it had the fastest permeability (Fig. 1). Moreover, as the fetus development

rate in embryos exposed to P10 for 10 min was equivalent to that of controls (Table 2), it was considered that the amount of damage due to osmotic expansion and cytotoxicity was extremely low. PEPeS is a vitrification solution comprising a cell-permeable cryoprotectant and non-cell-permeable cryoprotectant (sugar and high molecular weight substance; Table 3). Because sucrose

is effective for preventing cell damage due to osmotic expansion immediately after warming [3] and [10], 0.3 mol of sucrose was added to make the PEPeS isotonic to the SPB1 that was used for warming. A cell-permeable cryoprotectant was effective for vitrification of CPS [9], therefore propylene glycol and ethylene glycol were also added. The concentration of propylene glycol was fixed as the same concentration as that of the pretreatment solution to avoid cytotoxicity [14] and because a lower concentration Nitroxoline of propylene glycol would diffuse from the pretreated embryos to the CPS, which may reduce freezing tolerance. Even at high concentrations, the cytotoxicity of ethylene glycol is low [14]. In addition, cell permeability is lower for ethylene glycol than propylene glycol, and the toxic effects of ethylene glycol inside the cell are low (Fig. 1). Ethylene glycol was added to promote vitrification due to its low cytotoxicity. Titterington et al. Titterington et al. [21] added 50% Percoll to vitrification solution (50% glycerol, 0.5 mol sucrose, 50% Percoll in Ham’s F-10 medium).

Finally, we dichotomized our SEP measure to manual/non-manual cat

Finally, we dichotomized our SEP measure to manual/non-manual categories to ease construction of a long-term SEP measure. While dichotomizing the RGSC measure is a common and validated procedure, the meaning of social class (and the binary distinction) has become less relevant over time in the UK (with the increase in non-manual

service sector jobs such as call centers, for example). In summary, we have found evidence that material conditions, as well as smoking, are important mediators in the pathway between lower SEP and higher allostatic load. This is an important step in better understanding the pathways and mechanisms linking SEP, physiology and health. All authors declare that there are no conflicts Panobinostat chemical structure of interest. “
“The relationship between inflammation and depression in humans and in animal models is well-established. Individuals receiving immunotherapies have a higher learn more incidence of depressive symptoms (Capuron and Miller, 2011). Patients with major depressive disorders have higher levels of serum pro-inflammatory cytokines than healthy controls (Maes, 2011). Likewise, depressive phenotypes were observed in response to bacterial challenge (Brydon et al., 2008). These associations suggested that inflammation may result in depressive symptomatology mediated by neuroimmune mechanisms. Designed experiments using animal models

are offering insights into the relationship between selleck chemical infection, inflammation, and depression-like indicators.

Mice injected live attenuated Bacille Calmette-Guérin (BCG) displayed high circulatory pro-inflammatory cytokines and indoleamine 2,3-dioxygenase activity. These mice exhibited sickness behaviors encompassing reduction in body weight and locomotor activity from Day 5 to Day 7. Likewise, challenged mice demonstrated depressive-like behaviors including lower mobility in the tail suspension test and in the Porsolt forced swim test, and lower sucrose intake in the sucrose preference test from Day 7 to Day 30 after treatment (Moreau et al., 2008 and O’Connor et al., 2009). In addition, substantial mouse-to-mouse variation in response to BCG treatment was reported, including up to 30% of treated mice failing to exhibit adverse mobility effects (Platt et al., 2013). Reductionist approaches based on the analysis of individual components have dominated the study of complex behavioral responses to infection. However, these reductionist approaches could have hindered the identification and characterization of systemic responses across multiple and typically correlated behaviors. Six studies reported associations between BCG-treatment and sickness and depression-like behaviors in mice (Moreau et al., 2008, O’Connor et al., 2009, Kelley et al., 2013, Painsipp et al., 2013, Platt et al., 2013 and Vijaya et al., 2014). In these studies, behavioral indicators were analyzed separately.

Such a variant would have to be tested to determine whether cytop

Such a variant would have to be tested to determine whether cytoplasmic expression still confers the beneficial secretion-enhancing effects of full-length cytFkpA. As a consequence of the inability of overexpressed heterologous SB431542 ic50 proteins to fold properly in a timely fashion, misfolded proteins can be deposited in the form of cytoplasmic or periplasmic

inclusion bodies or they can be driven towards degradation (Georgiou et al., 1986, Betton et al., 1998 and Baneyx and Mujacic, 2004) Therefore, we isolated insoluble fractions of E. coli cells expressing XPA23 or ING1 Fabs, in the absence of cytFkpA, but we were unable to detect any Fab species by Western blot analysis (unpublished data), suggesting that no Fab was localized in inclusion bodies. Thus, we cannot support the notion that co-expression of cytFkpA increases the amount of functional Fab by means of improving its solubility. We hypothesize that misfolded or unfolded antibody fragment species serve as substrates for proteolytic degradation, instead of associating into inclusion bodies. We also demonstrate that co-expression of cytFkpA together with the kappa light chain-containing ING1 Fab expressed on a single tricistronic vector results in an improvement of functional Fab

secretion relative to expression in the absence of cytFkpA. Similarly, it previously was shown that the amounts of single chain antibodies expressed in

the periplasm of E. coli upon the co-expression selleck inhibitor of Skp were also increased when expression of both proteins was driven from a dicistronic vector ( Hayhurst and Harris, 1999). After observing the benefit of cytFkpA co-expression on Fab secretion, we evaluated its contribution to the antibody discovery process by incorporating the same expression platform with cytFkpA into phage panning selection and screening assays. The isolation of ideal lead candidates requires the design of methodologies allowing efficient screening of the libraries and exploitation of the vast repertoire of different library members. The choice of antibody formats (mostly scFv and Fab), the protein expression yields, the sequence Osimertinib diversity, the levels of display (i.e. on phage or yeast), and the ease and quality of in vitro screening are just a few of the factors that can impact the quality of antibody libraries (Mondon et al., 2008). In fact, it can be increasingly challenging to design screening assays that allow the identification of high-affinity library members and distinguish them from high-expressing clones since they are both able to display efficiently. Poorly expressed, functional library members are underrepresented and as a consequence, fail to be selected during screening. Thus, it is of paramount importance to maximize the solubility and functional expression of antibody library members.

Differences in knowledge scores between screenees

Differences in knowledge scores between screenees www.selleckchem.com/products/Everolimus(RAD001).html and non-screenees were assessed

using chi-square statistics. Between June 2009 and July 2010, 8844 citizens aged 50–74 were randomly allocated to colonoscopy (n = 5924) or to CT colonography (n = 2920). Of these invitees, 1194 (94%) colonoscopy screenees and 945 (96%) CT colonography screenees returned the questionnaire, and 915 (20%) of colonoscopy non-screenees and 257 (13%) of CT colonography non-screenees ( Fig. 1). Those invitees who initially indicated that they would like to participate, but changed their mind after the consultation with a research fellow or nurse, also received this questionnaire (n = 91 in colonoscopy and n = 105 in CT colonography). Twenty-seven questionnaires of colonoscopy screenees and 18 questionnaires of CT colonography screenees had to be excluded, as they were completed after the screening procedure. Both knowledge and attitude items were completed by 1032 of 1276 colonoscopy screenees Neratinib in vitro (81%), by 698 of 4648 colonoscopy non-screenees (15%), by 824 of 982 CT colonography screenees (84%) and by 192 of 1938 CT colonography non-screenees (10%). There was no difference between responding screenees and responding non-screenees in age or socio-economic status. In both colonoscopy and CT colonography non-screenees, women more often returned the questionnaire than men (Table 1). Overall, 99% of colonoscopy screenees and 98% of CT colonography screenees could

be classified as having adequate knowledge about colorectal cancer (screening) and the allocated screening modality, compared to 95% of colonoscopy Janus kinase (JAK) non-screenees and 92% of CT colonography non-screenees. Details are displayed in Table 2. Screenees: Five of the eight knowledge

statements on colorectal cancer and screening were answered correct by a large majority of colonoscopy and CT colonography screenees: statement 2 (97% versus 96%), 4 (98% versus 98%), 5 (96% versus 97%), 6 (98% versus 96%), and 7 (96% versus 94%). Non-screenees: Five out of eight knowledge statements on colorectal cancer and screening were answered correct by ≥86% of colonoscopy and CT colonography non-screenees: statement 2 (89% versus 91%), 3 (both 87%), 4 (both 94%), 6 (both 91%), and 7 (89% versus 86%). Screenees versus non-screenees: The largest difference between screenees and non-screenees in percentage of correct responses was found for the following statement: “if an invitee feels healthy, it is not useful to participate”: 96% of colonoscopy screenees indicated this was false versus 84% of non-screenees (p < 0.001). In the CT colonography group 97% of screenees indicated this was false versus 83% of non-screenees (p < 0.001). In colonoscopy invitees, the second largest difference was found for the following statement: “population based screening can detect colorectal cancer before it becomes symptomatic” (97% of screenees versus 89% of non-screenees indicated this was true; p < 0.001).

Furthermore, an analysis by the University of Wurzburg found a 9

Furthermore, an analysis by the University of Wurzburg found a 9.3% rate of local recurrence in patients with uncertain or positive margins treated with BCT (17). These findings suggest that if women with close or positive margins wish to proceed with BCT without reexcision, similar increased rates of IBTR would be expected regardless of whether they are treated with WBI or APBI. It is important, however, to emphasize that no direct comparison has

been made between WBI and APBI in PTC124 supplier our series and that we should wait for data from prospective randomized Phase III trials comparing WBI and APBI to make more informed decisions regarding the risks associated with close or positive margins in the setting of partial breast irradiation. With 6-year follow-up, the rate of IBTR was 8.7% for

close, 14.3% for positive, and 9.3% when pooled close and positive margins were combined. With these numbers at 6 years, as follow-up is extended beyond 10 years, local recurrences may exceed 20%. This suggests that in patients with close/positive margins, reexcision should be attempted initially if feasible. This represents one of the benefits of intracavitary brachytherapy over intraoperative radiation; target margins can be assessed before the treatment and the therapeutic plan adjusted based on these margin findings. Should patients be found www.selleckchem.com/PARP.html to have a close/positive margin and unable to undergo reexcision, the APBI course can be switched to a WBI course with boost therapy. Finally, when examining the IBTR in patients with close/positive margins, close to 80% of the failures were EFs, likely secondary to the high rate of EFs in DCIS patients with close/positive margins. These data are not consistent with the previous reports from Yale University and the British

Columbia Cancer Agency, which found the rate of EFs to be approximately 50% in patients undergoing BCT with WBI [18] and [19]. The etiology of this discrepancy may be that in patients with DCIS, positive/close margins may portend a risk of subclinical disease with potential multifocality/multicentricity. Also, the subjective nature of the TR/MM vs. elsewhere classification may play a role in the discrepancy. There are limitations to our analysis. Montelukast Sodium Although data were collected prospectively through the ASBrS Registry, this represents an unplanned retrospective analysis. Furthermore, owing to the small numbers of close/positive margin and limited number of failures, the power to detect differences was limited. This is likely the reason that the large differences seen in IBTR in this analysis were nonsignificant. Also, margin status is predicated on the extent of positive margins; however, the ASBrS Registry does not collect the extent of close or positive margins (number of positive margins, invasive vs. both invasive/noninvasive involvement, linear extent, attempts at reexcision, etc), which limits definitive conclusions on this information.

On one view, intention

to act is a perception-like experi

On one view, intention

to act is a perception-like experience that occurs when activity within frontal motor networks exceeds a threshold level (Fried et al., 2011, Hallett, 2007 and Matsuhashi and Hallett, 2008). On this view, the increased level of “motor noise” in GTS might require a more conservative threshold for detecting volition, in order to avoid excessive sensitivity to noise. This increased threshold would in turn produce delays in the perceived urge to move (Hallett, 2007) (see Fig. 1). This view therefore predicts that tic parameters should correlate with mean W judgement. Studies of developmental tic disorders could therefore http://www.selleckchem.com/products/SB-431542.html potentially clarify the processes whereby voluntary control emerges from the wider noise of involuntary sensorimotor activity, and becomes a characteristic cognitive and phenomenological event. In particular, we speculated that the experience of volition in GTS could resemble a perception-like signal selleckchem detection process, rather than a post hoc explanation of actions. Investigating this hypothesis would also provide an important

window into the learning process assumed to underlie the normal development of capacity for voluntary action. We therefore tested the experience of volition in 27 adolescents with GTS, and 30 healthy volunteers, using a cross-sectional design. We hypothesised that high levels of tics would be associated with delays in the normal experience of volition, because the characteristic neural activities that signal

one’s own volition would be lost in motor noise, delaying awareness of one’s own intentions. As a control for non-specific features of the task unrelated to volition, patients and controls also judged the perceived time of the keypress action itself. Twenty-seven adolescents (21 male) diagnosed with GTS aged between 10 and 17 years (mean age 13.7 years ± 2.3 SD) were recruited from the GTS outpatient clinic in the Department of Neurology, University Medical Center Hamburg-Eppendorf (clinical characteristics given in Supplementary Table 1). In two cases we were unable to collect scores on all clinical tests, so only 25 patients could be included in correlation analyses. The control group comprised 30 age-matched healthy control subjects (16 male, mean age 13 years ± 2.2 SD; range 10–17). All subjects and their parents gave their written informed consent Osimertinib concentration prior to study participation. The study was performed in accordance with the Declaration of Helsinki and was approved by the local ethics committee (PV4049). All subjects underwent a thorough clinical assessment (A.M., C.G.) based on a semi-structured neuropsychiatric interview adapted from Robertson and Eapen (Robertson & Eapen, 1996). DSM-IV-TR criteria were used for a diagnosis of GTS (American Psychiatric Association, 2000). Tic severity was determined using the Yale Global Tic Severity Scale (YGTSS) (Leckman et al., 1989) and the Modified Rush Video Scale (MRVS) (Goetz, Pappert, Louis, Raman, & Leurgans, 1999).