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Abstract Introduction Abnormal brain amyloid beta (Aβ) is typically assessed in vivo using global concentrations from cerebrospinal fluid and positron emission tomography (PET). However, it is unknown whether the assessment of the topographical distribution of Aβ pathology can provide additional information to identify, among global Aβ positive individuals, those destined for dementia. Methods We studied 260 amnestic mild cognitive impairment (MCI) subjects who were Aβ‐PET positive with [18F]florbetapir. Using [18F]florbetapir, we assessed the percentage of voxels sowing Aβ abnormality as well as the standardized uptake value ratio (SUVR) values across brain regions. Regressions tested the predictive effect of Aβ on progression to dementia over 2 years. Results Neither global nor regional [18F]florbetapir SUVR concentrations predicted progression to dementia. In contrast, the spatial extent of Aβ pathology in regions comprising the default mode network was highly associated with the development of dementia over 2 years. Discussion These results highlight that the regional distribution of Aβ abnormality may provide important complementary information at an individual level regarding the likelihood of Aβ positive MCI to progress to dementia.

One of the most challenging tasks of the post-genome-wide association studies (GWAS) research era is the identification of functional variants among those associated with a trait for an observed GWAS signal. Several methods have been developed to evaluate the potential functional implications of genetic variants. Each of these tools has its own scoring system, which forces users to become acquainted with each approach to interpret their results. From an awareness of the amount of work needed to analyze and integrate results for a single locus, we proposed a flexible and versatile approach designed to help the prioritization of variants by aggregating the predictions of their potential functional implications. This approach has been made available through a graphical user interface called DSNetwork, which acts as a single point of entry to almost 60 reference predictors for both coding and non-coding variants and displays predictions in an easy-to-interpret visualization. We confirmed the usefulness of our methodology by successfully identifying functional variants in four breast cancer and nine schizophrenia susceptibility loci.

Although crop tree release (CTR) in hardwood stands is an accepted variant of precommercial thinning (PCT), the lack of an affordable and feasible method hinders its adoption. CTR implies selecting between 150 and 500 trees ha when trees are between 7 and 12 m high and cutting only stems competing with the target crop trees. We performed a field trial of a CTR variant of PCT in a 27.8 ha hardwood stand using a backpack mounted chain saw. A detailed time study was performed to document the trial over 13 days. Compared to conventional PCT performed earlier in the life of a stand, precommercial crop tree release required cutting larger stems, which showed to be feasible and productive using a backpack mounted chain saw. Productivity varied between 0.22 to 0.47 ha h during the trial, Although productivity could vary with stand characteristics and worker, this proof of concept trial demonstrates some of the potential uses that this new saw configuration offers and sets the basis for an eventual larger scale deployment of this treatment.â1â1

Cet article fait état du renouvellement des pratiques de deux enseignantes du primaire lors d’une recherche-action. Utilisant principalement l’exposé oral pour enseigner et pour évaluer les élèves, les participantes de notre recherche ont transformé leurs pratiques en s’intéressant à l’oral pragmatique, une approche didactique qui consiste à développer les capacités des élèves à communiquer oralement tout en les sensibilisant aux enjeux d’une communication harmonieuse. Les résultats présentés font état, dans un premier temps de la réflexion des participantes les menant vers le choix de l’objet à enseigner. Ensuite, la planification, l’enseignement et l’activité de mise en pratique de l’objet de l’oral choisi sont explicités.

The drug targets IL23 and IL12 regulate pathogenicity and plasticity of intestinal Th17 cells in Crohn's disease (CD) and ulcerative colitis (UC), the two most common inflammatory bowel diseases (IBD). However, studies examining Th17 dysregulation in mesenteric lymph nodes (mLNs) of these patients are rare. We showed that in mLNs, CD could be distinguished from UC by increased frequencies of CCR6+CXCR3−RORγ+Tbet−CD4+ (Th17) memory T cells enriched in CD62Llow effector memory T cells (TEM), and their differentially expressed molecular profile. Th17 TEM cells (expressing IL17A, IL17F, RORC, and STAT3) displayed a higher pathogenic/cytotoxic (IL23R, IL18RAP, and GZMB, CD160, PRF1) gene signature in CD relative to UC, while non-pathogenic/regulatory genes (IL9, FOXP3, CTLA4) were more elevated in UC. In both CD and UC, IL12 but not IL23, augmented IFNγ expression in Th17 TEM and switched their molecular profile toward an ex-Th17 (Th1*)-biased transcriptomic signature (increased IFNG, and decreased TCF7, IL17A), suggesting that Th17 plasticity occurs in mLNs before their recruitment to inflamed colon. We propose that differences observed between Th17 cell frequencies and their molecular profile in CD and UC might have implications in understanding disease pathogenesis, and thus, therapeutic management of patients with IBD.

El artículo tiene por finalidad exponer aspectos del quehacer de investigación que se lleva a cabo en el Observatorio de la Educación Nacional y Regional (OBSED)- del Instituto de Investigación en Educación (INIE). Se hace un breve análisis acerca de las políticas públicas en educación adoptadas durante los últimos años por los países de Centroamérica, marcadas especialmente por las políticas del Banco Mundial y de la UNESCO. El análisis conduce, en particular, a reflexionar sobre la política educativa costarricense, situándola en el contexto de los perfiles laborales que demanda el mercado de trabajo vinculado a la globalización económica, así como en relación con las desigualdades sociales estructurales, la inequidad, y el incremento de la pobreza que se registra en los países de la región centroamericana. Se aborda también el análisis de dos aspectos centrales que determinan las políticas públicas en educación: los enfoques y estrategias de evaluación de los procesos y los sistemas educativos y la dimensión de la interculturalidad como una necesidad epistémica/pedagógica insoslayable, que debe ser incorporada en los procesos educativos, a fin de avanzar en atender y resolver las situaciones de la inequidad, la desigualdad y la exclusión educativa estructural. Se tiene por finalidad poner en perspectiva la necesidad de una educación que reconozca y releve las necesidades y expectativas de las personas y las comunidades situadas en sus respectivas realidades socioculturales, en relación con el análisis y la reflexión acerca de los procesos socio/educativos en el país y en América Latina y el Caribe.

Background: White matter changes are hypothesized to be among the earliest changes occurring in the course of Alzheimer's disease (AD). We investigated associations between AD pathology, namely amyloid and tau, and white matter microstructural changes in cognitively unimpaired individuals at risk of AD dementia. We expected higher levels of pathology to be related to lower free‐water‐corrected fractional anisotropy. Method: We studied 223 cognitively normal older adults with PET and multi‐shell diffusion MRI from the PREVENT‐AD cohort. We first measured standardized uptake value ratios (SUVRs) in 40 brain regions for amyloid‐β (Aβ, i.e., lateral and medial prefrontal, parietal, lateral temporal, and cingulate cortical regions in both hemispheres) and 26 brain regions for tau (i.e., Braak stages I, III, and IV). We then used TractSeg, a deep learning framework, to segment 49 well‐established white matter bundles. We mapped free‐water‐corrected fractional anisotropy (FAT) in those bundles. Lastly, to explore the relationships between AD pathology and white matter microstructure across bundles, we applied two separate partial least squares analyses: one for Aβ pathology and one for tau (Figure 1). Result: We found one significant latent variable relating Aβ pathology to FAT. Specifically, higher levels of Aβ pathology were associated with the combination of higher levels of FAT within the rostral body of the uncinate fascicle and superior longitudinal fascicle (Figure 2A). We found two significant latent variables relating tau pathology to FAT for which higher levels of tau pathology were associated with elevated FAT within the uncinate fascicle, thalamo‐occipital bundle, optic radiation, inferior occipitofrontal fascicle, inferior longitudinal fascicle, middle longitudinal fascicle, etc. (Figure 2B). Conclusion: In cognitively unimpaired individuals at risk of AD, increased Aβ and tau pathology were associated with higher levels of FAT in AD‐related bundles. These unexpected findings may suggest an inverted U‐shape pattern between AD pathology and FAT in the preclinical phase of AD for which FAT values would start by increasing before decreasing later in the course of the disease. This first increase might be a marker of early pathological processes such as neuroinflammation or swelling. [ABSTRACT FROM AUTHOR]

Background: Females and individuals with a family history (FH) of Alzheimer's disease (AD) are considered at higher risk of sporadic AD. However, how sex and maternal/paternal heredity affects in vivo AD biomarkers is not well understood. Our objectives were to 1) assess if females or individuals with a first‐degree maternal FH of AD accumulate amyloid‐beta (Aβ) and/or tau faster than males or individuals with a first‐degree paternal FH of AD and 2) assess if both could influence the rate of Aβ driving tau in preclinical AD. Method: Two hundred and thirty‐five older adults (age 68.3 ± 5.1 years, 69.8% female) from the PREVENT‐AD cohort, cognitively unimpaired at baseline, underwent [18F]‐NAV4694 and [18F]‐AV1451 positron emission tomography (PET) scans. Longitudinal PET scans were available for 106 individuals (4.3 ± 0.4 years follow‐up). We extracted and averaged the standard uptake value ratio (SUVr) in fronto‐parietal regions for Aβ and in temporal regions for tau. We performed t‐tests and ANOVA models to assess sex or maternal/paternal FH (FHsex) differences in Aβ and tau burden or annual change. We then performed linear regression models with an interaction term between Aβ and sex (or Aβ and FHsex) on tau burden and annual change, plus additional models to adjust for age and education. Result: Sex and FHsex differences on Aβ and tau burden or annual rate of change did not reach significance although females tended to have higher tau SUVr at baseline (p = 0.053) (Figure 1 & 2). We found an interaction between Aβ and sex (훽 = ‐0.13, p = 0.008), and between Aβ and FHsex (훽 = 0.11, p = 0.03), on tau at baseline (Figure 3) suggesting that, for the same level of Aβ burden, females and individuals with paternal FH of AD had higher tau burden than males and individuals with maternal FH of AD. Results were similar when adjusted for age and education. Conclusion: Females and individuals with a paternal FH of AD might need less Aβ before developing AD‐related tau, but did not accumulate tau faster. Identifying individuals more vulnerable to AD pathology, by disentangling sex‐specific effects, would help to design personalized interventions for AD. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Plasma biomarkers are altered years prior to Alzheimer's disease (AD) clinical onset. METHODS: We measured longitudinal changes in plasma amyloid‐beta (Aβ)42/40 ratio, pTau181, pTau231, neurofilament light chain (NfL), and glial fibrillary acidic protein (GFAP) in a cohort of older adults at risk of AD (n = 373 total, n = 229 with Aβ and tau positron emission tomography [PET] scans) considering genetic and demographic factors as possible modifiers of these markers' progression. RESULTS: Aβ42/40 ratio concentrations decreased, while NfL and GFAP values increased over the 4‐year follow‐up. Apolipoprotein E (APOE) ε4 carriers showed faster increase in plasma pTau181 than non‐carriers. Older individuals showed a faster increase in plasma NfL, and females showed a faster increase in plasma GFAP values. In the PET subsample, individuals both Aβ‐PET and tau‐PET positive showed faster plasma pTau181 and GFAP increase compared to PET‐negative individuals. DISCUSSION: Plasma markers can track biological change over time, with plasma pTau181 and GFAP markers showing longitudinal change in individuals with preclinical AD. Highlights: Longitudinal increase of plasma pTau181 and glial fibrillary acidic protein (GFAP) can be measured in the preclinical phase of AD.Apolipoprotein E ε4 carriers experience faster increase in plasma pTau181 over time than non‐carriers.Female sex showed accelerated increase in plasma GFAP over time compared to males.Aβ42/40 and pTau231 values are already abnormal at baseline in individuals with both amyloid and tau PET burden. [ABSTRACT FROM AUTHOR]

Ice machines in healthcare facilities have been suspected and even linked to outbreaks and pseudo-outbreaks. Guidelines exist for maintenance of these devices but there is no clear independent infection control standard, and little is known about their microbial contamination. To evaluate the microbial contamination, amplification, and presence of opportunistic pathogens in ice-water machines in a healthcare facility. Concentrations of general microbial indicators (heterotrophic plate counts (HPC), total and intact cells), faecal indicators (enterococci) and opportunistic pathogens (Pseudomonas aeruginosa , non-tuberculous mycobacteria (NTM), Candida spp.) were measured in 36 ice-water machines on patient wards of a 772-bed hospital. Profile sampling was performed on five ice-water machines and adjacent faucets to identify sites of microbial proliferation. Candida spp. were found in half of ice-water samples while enterococci and P. aeruginosa were present in six and 11 drain inlets respectively. NTM were measured in all ice-water samples and 35 out of 36 biofilms. Pre-filters and ice machines are sites for additional amplification: NTM densities were on average 1.3 log 10 higher in water of ice machine flushed 5 min compared to flushed adjacent tap water. Ice machine design needs to be adapted to reduce microbial proliferation. The absence of correlation between HPC densities (current microbial indicators) and NTM concentrations suggests a need for cleaning efficiency indicators better correlated with opportunistic pathogens. Cleaning and disinfection guidelines of ice machines in healthcare facilities need to be improved, especially when ice is given to the most vulnerable patients, and NTM may be an efficiency indicator. [ABSTRACT FROM AUTHOR]

Inadequate representation of the human tissue environment during a preclinical screen can result in inaccurate predictions of compound effects. Consequently, pharmaceutical investigators are searching for preclinical models that closely resemble original tissue for predicting clinical outcomes.The current research aims to compare the impact of using serum-free medium instead of complete culture medium during the last step of psoriatic skin substitute reconstruction. Skin substitutes were produced according to the self-assembly approach.Serum-free conditions have no negative impact on the reconstruction of healthy or psoriatic skin substitutes presented in this study regarding their macroscopic or histological appearances. ATR-FTIR results showed no significant differences in the CH2 bands between psoriatic substitutes cultured with or without serum, thus suggesting that serum deprivation did not have a negative impact on the lipid organization of their stratum corneum. Serum deprivation could even lead to a better organization of healthy skin substitute lipids. Percutaneous analyses demonstrated that psoriatic substitutes cultured in serum-free conditions showed a higher permeability to hydrocortisone compared to controls, while no significant differences in benzoic acid and caffeine penetration profiles were observed.Results obtained with this 3D-psoriatic skin substitute demonstrate the potential and versatility of the model. It could offer good prediction of drug related toxicities at preclinical stages performed in order to avoid unexpected and costly findings in the clinic.Together, these findings offer a new approach for one of the most important challenges of the 21st century, namely, prediction of drug toxicity.•Impact of serum-free conditions during psoriatic skin substitutes reconstruction.•Lipids disorganization of healthy and psoriatic skin substitutes.•Permeation profiles of healthy skin substitutes.•Permeation profiles of psoriatic skin substitutes.•Potential and veratility of a 3d-reconstructed model to perform dermatological testing.

A region on chromosome 19p13 is associated with the risk of developing ovarian and breast cancer. Here, the authors genotyped SNPs in this region in thousands of breast and ovarian cancer patients and identified SNPs associated with three genes, which were analysed with functional studies.

Les centres de littératie sont un dispositif d’enseignement-apprentissage qui permet l’enseignement et l’apprentissage de la lecture, de l’écriture ainsi que de la communication orale (Diller, 2010; Nations et Alonso 2001; Owocki, 2005; Swartz et all, 2003). Toutefois, on en sait bien peu sur l’enseignement et l’apprentissage de l’oral dans ces centres. À l’aide d’une recherche exploratoire, nous décrivons la place et le statut de l’oral dans ces centres dans une classe de deuxième année du primaire à partir de l’entrevue de deux enseignantes et d’observations dans une classe.

Oestrogen negative breast cancer is associated with a poor prognosis. In this study, the authors perform a meta-analysis of 11 breast cancer genome-wide association studies and identify four new loci associated with oestrogen negative breast cancer risk. These findings may aid in stratifying patients in the clinic.

Background: [18F]THK5351 is a tau positron emission tomography tracer that has shown promise in quantifying tau distribution in tauopathies such as Alzheimer's disease (AD) and progressive supranuclear palsy (PSP). However, the interpretation of [18F]THK5351 uptake has been shown to be confounded by high monoamine oxidase B (MAO-B) availability across the brain in AD. Objectives: To test the hypothesis that the MAO-B inhibitor, rasagiline reduces [18F]THK5351 uptake in PSP. Methods: Six individuals (4: PSP; 2: cognitively unimpaired, CU) underwent [18F]THK5351 and [18F]AZD4694 to quantify baseline tau and amyloid deposition, respectively. Following a 10-day course of 1 mg rasagiline, all participants received a post-challenge [18F]THK5351 scan. The baseline and post-rasagiline challenge standardized uptake value (SUV) were generated normalized for patient weight and injected radioactivity. Results: The post-rasagiline regional SUV was reduced on average by 69–89% in PSP, and 53–81% in CU. The distributions of post-rasagiline [18F]THK5351 SUV among PSP individuals were not consistent with the typical pattern of tau aggregates in PSP. Conclusions: Similar to AD, the interpretation of [18F]THK5351 uptake in PSP is likely confounded by off-target binding to MAO-B binding sites. [18F]THK5351 is not sufficient in quantifying tau aggregates in PSP using the proposed rasagiline dosing regimen. Keywords: [18F]THK5351 tau tracer, Monoamine oxidase-B, Rasagiline, Progressive Supranuclear Palsy, Positron emission tomography

Bacterial gene transfer agents (GTAs) are small virus-like particles that package DNA fragments and inject them into cells. They are encoded by gene clusters resembling defective prophages, with genes for capsid head and tail components. These gene clusters are usually assumed to be maintained by selection for the benefits of GTA-mediated recombination, but this has never been tested. We rigorously examined the potential benefits of GTA-mediated recombination, considering separately transmission of GTA-encoding genes and recombination of all chromosomal genes. In principle GTA genes could be directly maintained if GTA particles spread them to GTA- cells often enough to compensate for the loss of GTA-producing cells. However, careful bookkeeping showed that losses inevitably exceed gains for two reasons. First, cells must lyse to release particles to the environment. Second, GTA genes are not preferentially replicated before DNA is packaged. A simulation model was then used to search for conditions where recombination of chromosomal genes makes GTA+ populations fitter than GTA- populations. Although the model showed that both synergistic epistasis and some modes of regulation could generate fitness benefits large enough to overcome the cost of lysis, these benefits neither allowed GTA+ cells to invade GTA- populations, nor allowed GTA+ populations to resist invasion by GTA- cells. Importantly, the benefits depended on highly improbable assumptions about the efficiencies of GTA production and recombination. Thus, the selective benefits that maintain GTA gene clusters over many millions of years must arise from consequences other than transfer of GTA genes or recombination of chromosomal genes.

It is commonly accepted that tree form has an impact on the productivity of single-grip harvesters. However, it remains unclear, which elements of tree form are significant and to what degree they impact harvesting productivity. This is of particular importance in hardwood dominated stands, where hardwood trees often exhibit complex and variable stem and crown architecture that can complicate and prolong the processing phase. With the development of specialized harvesting heads, hardwoods, which were mostly subject to motor-manual operations, are now increasingly being cut and processed with fully mechanized harvesting systems. The goal of this pilot project was to determine the effect of tree form on the productivity of mechanized cut-to-length harvesting. A time and motion study of a single-grip harvester, operating in a hardwood dominated stand, suggests that the presence of a fork or a large branch on the main stem can reduce machine harvesting productivity by 15 to 20%.

Background: Intracellular accumulation of tau tangles in the brain is one of the most prominent manifestations of Alzheimer's disease (AD). Progression thereof across the AD stages has specific temporal and spatial patterns, wherein time is informative of space and vice versa. Here we introduce a novel method, Manifold Component Analysis (MCA), to represent tangle accumulation in 2D, reflecting the spatial aspect of tau propagation stages to further relate it to the temporal aspect thereof. Method: MCA represents a neuroinformatics technique serving to smooth out transitions between neighbouring Braak stage regions (Fig. 1A) and thus creating "sub‐stages" (Fig. 1B) which are subsequently used to sample neocortical (tau tangle) data and represent them in a continuous 2D graph with the spatially earliest sub‐stage appearing in the leftmost, and the latest spatial sub‐stage appearing on the right (Fig. 1C). This method was applied to 18F‐MK‐6240 tau PET tracer data from the TRIAD cohort (https://triad.tnl‐mcgill.com/; N = 753; 123 AD, 170 MCI, 416 cognitively unimpaired). Result: We obtained MCA profiles of tau‐PET for each subject in the cohort, and evaluated them across multiple visits (Fig. 1D; mean inter‐visit interval 1.9 years), showing that the largest change (about 25%) occurs at stages 4 and 5. Partial correlations between sub‐stages within the MCA profiles for each subject, and their corresponding neuropsychological assessment measurements showed unique spatial signatures for each specific cognitive test, generally favouring earlier stage correlations for memory, and later stage correlations for higher cognition (Fig. 1E); the covariates included age, sex, APOEe4 status and years of education. Conclusion: The MCA method proves useful as an intuitive lookup tool for tau tangle accumulation across the brain in AD. The obtained profiles help resolve correspondence between "space" and "time" contexts of the pathology spread, as well as the spatial aspect of the timeline of cognitive decline. As MCA is a subject‐specific, easily applicable, fast and extensible technique, numerous new applications and extensions will follow, providing a necessary aid in staging, forecasting, and potentially treating AD. [ABSTRACT FROM AUTHOR]

Our study reveals a non-canonical role for CCL2 in modulating non-macrophage, myeloid-derived suppressor cells (MDSCs) and shaping a tumor-permissive microenvironment during colon cancer development. We found that intratumoral CCL2 levels increased in patients with colitis-associated colorectal cancer (CRC), adenocarcinomas, and adenomas. Deletion of CCL2 blocked progression from dysplasia to adenocarcinoma and reduced the number of colonic MDSCs in a spontaneous mouse model of colitis-associated CRC. In a transplantable mouse model of adenocarcinoma and an APC-driven adenoma model, CCL2 fostered MDSC accumulation in evolving colonic tumors and enhanced polymorphonuclear (PMN)-MDSC immunosuppressive features. Mechanistically, CCL2 regulated T cell suppression of PMN-MDSCs in a STAT3-mediated manner. Furthermore, CCL2 neutralization decreased tumor numbers and MDSC accumulation and function. Collectively, our experiments support that perturbing CCL2 and targeting MDSCs may afford therapeutic opportunities for colon cancer interception and prevention.

Phages have a major impact on microbial populations. In this work, we discuss how predation, transduction, lysogeny, and phage domestication lead to symbio-centric genomic interactions between bacteria and phages, ranging from antagonistic to mutualistic. Furthermore, these interactions influence bacterial diversification and ecotype formation. We then propose an additional consideration in the form of a symbio-centric ecological speciation framework for bacteria. Our framework builds upon classical morphological and molecular taxonomy by also considering bacteria and their phages as a unit of evolutionary selection. This framework acknowledges the considerable effect that phage interaction has on bacterial genomic content, regulation, and evolution, and will advance our understanding of bacterial evolution.

To evaluate intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) sequences for quantitative characterization of anal fistula activity.This retrospective study was approved by the institutional review board. One hundred and two patients underwent MRI for clinical suspicion of anal fistula. Forty-three patients with demonstrable anal fistulas met the inclusion criteria. Quantitative analysis included measurement of DCE and IVIM parameters. The reference standard was clinical activity based on medical records. Statistical analyses included Bayesian analysis with Markov Chain Monte Carlo, multivariable logistic regression, and receiver operating characteristic analyses.Brevity of enhancement, defined as the time difference between the wash-in and wash-out, was longer in active than inactive fistulas (p = 0.02). Regression coefficients of multivariable logistic regression analysis revealed that brevity of enhancement increased and normalized perfusion area under curve decreased with presence of active fistulas (p = 0.03 and p = 0.04, respectively). By cross-validation, a logistic regression model that included quantitative perfusion parameters (DCE and IVIM) performed significantly better than IVIM only (p < 0.001). Area under the curves for distinguishing patients with active from those with inactive fistulas were 0.669 (95% confidence interval [CI]: 0.500, 0.838) for a model with IVIM only, 0.860 (95% CI: 0.742, 0.977) for a model with IVIM and brevity of enhancement, and 0.921 (95% CI: 0.846, 0.997) for a model with IVIM and all DCE parameters.The inclusion of brevity of enhancement measured by DCE-MRI improved assessment of anal fistula activity over IVIM-DWI only.

BACKGROUND: Clinical experiences of adults who underwent surgery for esophageal atresia at birth is limited. There is some evidence that suggests considerable long-term morbidity, partly because of dysphagia, which has been reported in up to 85% of adult patients who undergo surgery for esophageal atresia. The authors hypothesized that dysphagia in this population is caused by dysmotility and/or anatomical anomalies.

The article discusses the need for mathematical literacy in our world today and shares results from the 2003 PISA assessment of mathematical literacy. Some ideas are presented for incorporating similar problems in the classroom. (Contains 4 figures and 3 tables.)

This study combined the activity involvement and place attachment scores of trout anglers at Montauk State Park (Missouri, USA) into a typology of recreation specialization. The framework was used to explain anglers' knowledge of park resources. Highly specialized anglers were more knowledgeable about the park than those who were less specialized. Although utilization of interpretive media was related to resource knowledge, this relationship was fairly weak. These findings suggest that a visitor segmentation procedure based on recreation specialization can be a useful way to accomplish some management objectives at state parks, such as environmental education. (Contains 3 tables.)

The rising tide of numbers and statistics in daily life signals a need for a fundamental broadening of the concept of literacy: mathematical literacy assuming a coequal role in the curriculum alongside language-based literacy. Mathematical literacy is not about studying higher levels of formal mathematics, but about making math relevant and empowering for everyone. Situating mathematical literacy as a major curricular focus requires making mathematics a transparent part of structuring problems and making decisions across all facets of the school curriculum. If students are to "identify and understand the role that mathematics plays in the world," they need to experience the power of mathematics in industrial technology, physical education, history, business, and physics. For this to happen, all teachers will have to buy into the need for mathematics and its applications in their disciplines. This will require efforts to coordinate the language, symbolism, and topics in non-mathematics classes with the prerequisite knowledge and skills from mathematics classes. One format for structuring classes to promote mathematical literacy is the launch-explore-reflect model employed by some of the recently developed curricular programs for middle level and high school mathematics. (Contains 1 figure.)

Although park naturalists should be inclusive in their attempts to reach a variety of audiences, visitors having a consumptive resource orientation may get overlooked. The activity involvement, place attachment and resource knowledge scores of trout anglers at Montauk State Park (Missouri, USA) were combined into a typology that consisted of four levels of recreation specialization (least, moderately, very and most). This continuum was used to explain anglers' usage and evaluation of nonformal environmental education services at the park. A total of 532 trout anglers completed questionnaires during the summer of 2003. Results showed that specialized anglers participated more in educational opportunities than those who were less specialized. Each of level of the continuum was mutually exclusive. Nearly three-fourths of the trout anglers (72.8%) believed that environmental education was important and that the park was doing a good job of providing this type of service. A positive trend between levels of specialization and evaluation of environmental education was observed. This study indicated that a segmentation procedure based on recreation specialization can be useful to accomplish some key park management objectives, such as environmental literacy. (Contains 2 figures and 2 tables.)

Proof and reasoning are fundamental aspects of mathematics. Yet, how to help students develop the skills they need to engage in this type of higher-order thinking remains elusive. In order to contribute to the dialogue on this subject, we share results from a classroom-based interpretive study of teaching and learning proof in geometry. The goal of this research was to identify factors that may be related to the development of proof understanding. In this paper, we identify and interpret students' actions, teacher's actions, and social aspects that are evident in a classroom in which students discuss mathematical conjectures, justification processes and student-generated proofs. We conclude that pedagogical choices made by the teacher, as manifested in the teacher's actions, are key to the type of classroom environment that is established and, hence, to students' opportunities to hone their proof and reasoning skills. More specifically, the teacher's choice to pose open-ended tasks (tasks which are not limited to one specific solution or solution strategy), engage in dialogue that places responsibility for reasoning on the students, analyze student arguments, and coach students as they reason, creates an environment in which participating students make conjectures, provide justifications, and build chains of reasoning. In this environment, students who actively participate in the classroom discourse are supported as they engage in proof development activities. By examining connections between teacher and student actions within a social context, we offer a first step in linking teachers' practice to students' understanding of proof.

Promoting discussion and argumentation of mathematical ideas among students are aspects of the vision for communication in recent school mathematics reform efforts. Having rich mathematical discussions, however, can present a variety of classroom challenges. Many factors influence classroom discussions and need to be addressed in ways that will assist teachers in creating more inquiry-based mathematics classrooms. The study presented here examined the development of mathematical discussions in a fifth-grade classroom over the course of a school year. Various aspects of the participants' interactions, teacher's pedagogy, and the classroom microculture were investigated. One major result is the evolution of student participation from nonactive listening to active listening and use of others' ideas to develop new conjectures. These changes were paralleled by changes in the teacher's role in the classroom and the nature of her questions, in particular.

This study examined the interaction between college students' attachment orientation and mentors' relational style in the prediction of students' behaviors and perceptions in academic mentoring and of their subsequent academic achievement. Ninety college students were administered the Adult Attachment Interview and their professors-mentors completed the Attachment Style Questionnaire. Students displayed more adaptive behaviors and perceptions in mentoring and earned higher grades when their attachment orientation was in contrast to their mentor's relational style. Implications for the practice of academic mentoring in college are discussed.

La masonerÌa cubana, que aparece en los primeros aÒos del siglo XIX, no llegÛ a consolidarse hasta la dÈcada de los setenta, en un contexto colonial esclavista. La integraban y dirigÌan entonces actores sociales que, al acabar la primera guerra de independencia (1868 - 1878), buscaron en la corriente autonomista una nueva vÌa polÌtica. El progresismo que asumÌan les condujo a cuestionar, tanto en su vida profana como masónica, la situaciÛn de los grupos sociales marginados y reflexionar sobre su integraciÛn no sólo en la sociedad civil sino tambiÈn en la masonerÌa. La iniciaciÛn de las mujeres y de los negros se convirtiÛ en este sentido en una preocupaciÛn para esos arquitectos de una masonerÌa en b ̇squeda de una identidad y de un reconocimiento internacional. Este proceso se caracterizó por una voluntad de reformas y apertura social al tiempo que la aplicaciÛn de las reglas de la regularidad masÛnica limitaron sus efectos.