Cerebellar Pathology Does Not Impair Performance on Identification or Categorization Tasks

In comparison to the basal ganglia, prefrontal cortex, and medial temporal lobes, the cerebellum has been absent from recent research on the neural substrates of categorization and identification, two prominent tasks in the learning and memory literature. To investigate the contribution of the cerebellum to these tasks, we tested patients with cerebellar pathology (seven with bilateral degeneration, six with unilateral lesions, and two with midline damage) on rule-based and information-integration categorization tasks and an identification task. In rule-based tasks, it is assumed that participants learn the categories through an explicit reasoning process. In information-integration tasks, optimal performance requires the integration of information from multiple stimulus dimensions, and participants are typically unaware of the decision strategy. The identification task, in contrast, required participants to learn arbitrary, color-word associations. The cerebellar patients performed similar to matched controls on all three tasks and performance did not vary with the extent of cerebellar pathology. Although the interpretation of these null results requires caution, these data contribute to the current debate on cerebellar contributions to cognition by providing boundary conditions on understanding the neural substrates of categorization and identification, and help define the functional domain of the cerebellum in learning and memory.

Assessment of English Language Learners Seeking a Graduate Degree in Speech Language Pathology

A shortage of bilingual/bicultural speech language pathologists may reflect a problem with recruitment and retention of bilingual/bicultural students. The purpose of the present study was to survey graduate training programs in speech language pathology to determine typical policies and practices concerning students who apply and are admitted as ELLs. With a growing number of ELL children needing services from a bilingual SLP, it seems that little is being done to address the issue. The problem may be with the reluctance of programs to not only accept ELL students, but there also seems to be a disinclination for any sort of training program to be established for these ELL students. Clinic directors were asked to complete a survey about ELLs seeking clinical training in speech language pathology. In particular, we were interested in obtaining information about whether clinical training programs a) provided opportunities for ELL to participate in clinic, b) assessed the English skills of these students, and c) provided remediation if these students English skills were judged to be less than proficient.

Measurement of isotopic uranium in water for compliance monitoring by liquid scintillation counting with alpha/beta discrimination

A simple and inexpensive method is described for analysis of uranium (U) activity and mass in water by liquid scintillation counting using $\alpha$/$\beta$ discrimination. This method appears to offer a solution to the need for an inexpensive protocol for monitoring U activity and mass simultaneously and an alternative to the potential inaccuracy involved when depending on the mass-to-activity conversion factor or activity screen.^ U is extracted virtually quantitatively into 20 ml extractive scintillator from a 1-$\ell$ aliquot of water acidified to less than pH 2. After phase separation, the sample is counted for a 20-minute screening count with a minimum detection level of 0.27 pCi $\ell\sp{-1}$. $\alpha$-particle emissions from the extracted U are counted with close to 100% efficiency with a Beckman LS6000 LL liquid scintillation counter equipped with pulse-shape discrimination electronics. Samples with activities higher than 10 pCi $\ell\sp-1$ are recounted for 500-1000 minutes for isotopic analysis. Isotopic analysis uses events that are automatically stored in spectral files and transferred to a computer during assay. The data can be transferred to a commercially available spreadsheet and retrieved for examination or data manipulation. Values for three readily observable spectral features can be rapidly identified by data examination and substituted into a simple formula to obtain $\sp{234}$U/$\sp{238}$U ratio for most samples. U mass is calculated by substituting the isotopic ratio value into a simple equation.^ The utility of this method for the proposed compliance monitoring of U in public drinking water supplies was field tested with a survey of drinking water from Texas supplies that had previously been known to contain elevated levels of gross $\alpha$ activity. U concentrations in 32 samples from 27 drinking water supplies ranged from 0.26 to 65.5 pCi $\ell\sp{-1}$, with seven samples exceeding the proposed Maximum Contaminant Level of 20 $\mu$g $\ell\sp{-1}$. Four exceeded the proposed activity screening level of 30 pCi $\ell\sp{-1}$. Isotopic ratios ranged from 0.87 to 41.8, while one sample contained $\sp{234}$U activity of 34.6 pCi $\ell\sp{-1}$ in the complete absence of its parent, $\sp{238}$U. U mass in the samples with elevated activity ranged from 0.0 to 103 $\mu$g $\ell\sp{-1}$. A limited test of screening surface and groundwaters for contamination by U from waste sites and natural processes was also successful. ^

Differential roles of Ca2+/calmodulin-dependent kinases in posttetanic potentiation at input selective glutamatergic pathways

The electrosensory lateral line lobe (ELL) of the electric fish Apteronotus leptorhynchus is a layered medullary region receiving electroreceptor input that terminates on basal dendrites of interneurons and projection (pyramidal) cells. The molecular layer of the ELL contains two distinct glutamatergic feedback pathways that terminate on the proximal (ventral molecular layer, VML) and distal (dorsal molecular layer) apical dendrites of pyramidal cells. Western blot analysis with an antibody directed against mammalian Ca2+/calmodulin-dependent kinase 2, α subunit (CaMK2α) recognized a protein of identical size in the brain of A. leptorhynchus. Immunohistochemistry demonstrated that CaMK2 α expression in the ELL was restricted to fibers and terminals in the VML. Posttetanic potentiation (PTP) could be readily elicited in pyramidal cells by stimulation of either VML or DML in brain slices of the ELL. PTP in the VML was blocked by extracellular application of a CaMK2 antagonist (KN62) while intracellular application of KN62 or a CaMK2 inhibitory peptide had no effect, consistent with the presynaptic localization of CaMK2 α in VML. PTP in the dorsal molecular layer was not affected by extracellular application of KN62. Anti-Hebbian plasticity has also been demonstrated in the VML, but was not affected by KN62. These results demonstrate that, while PTP can occur independent of CaMK2, it is, in some synapses, dependent on this kinase.

The human formin-binding protein 17 (FBP17) interacts with sorting nexin, SNX2, and is an MLL-fusion partner in acute myelogeneous leukemia

We have cloned a fusion partner of the MLL gene at 11q23 and identified it as the gene encoding the human formin-binding protein 17, FBP17. It maps to chromosome 9q34 centromeric to ABL. The gene fusion results from a complex chromosome rearrangement that was resolved by fluorescence in situ hybridization with various probes on chromosomes 9 and 11 as an ins(11;9)(q23;q34)inv(11)(q13q23). The rearrangement resulted in a 5′-MLL/FBP17-3′ fusion mRNA. We retrovirally transduced murine-myeloid progenitor cells with MLL/FBP17 to test its transforming ability. In contrast to MLL/ENL, MLL/ELL and other MLL-fusion genes, MLL/FBP17 did not give a positive readout in a serial replating assay. Therefore, we assume that additional cooperating genetic abnormalities might be needed to establish a full malignant phenotype. FBP17 consists of a C-terminal Src homology 3 domain and an N-terminal region that is homologous to the cell division cycle protein, cdc15, a regulator of the actin cytoskeleton in Schizosaccharomyces pombe. Both domains are separated by a consensus Rho-binding motif that has been identified in different Rho-interaction partners such as Rhotekin and Rhophilin. We evaluated whether FBP17 and members of the Rho family interact in vivo with a yeast two-hybrid assay. None of the various Rho proteins tested, however, interacted with FBP17. We screened a human kidney library and identified a sorting nexin, SNX2, as a protein interaction partner of FBP17. These data provide a link between the epidermal growth factor receptor pathway and an MLL fusion protein.

Inoculação com leveduras e exposição ao ar modificam o valor nutritivo de silagem de milho para vacas leiteiras

Silagens de milho são mais propensas à deterioração quando expostas ao ar. As leveduras assimiladoras de ácido lático são frequentemente os primeiros microrganismos a iniciar a deterioração aeróbia nas silagens. Alguns estudos reportam que silagem de milho aerobicamente instável está associada à redução no consumo, na produção de leite e depressão no teor de gordura do leite. Portanto, o objetivo deste estudo foi avaliar a influência de inoculação de leveduras (Pichia norvegensis) e a exposição ao ar por 48 horas sobre o valor nutritivo das silagens e o desempenho de vacas leiteiras. O milho foi colhido com 34% de MS, tratado sem (Controle) ou com P. norvegensis, na dose 1×105 ufc/g MV (Levedura) e armazenado silos tipo bolsa (40 t/silo). Após 123 dias de armazenamento, os silos foram abertos e a silagem foi fornecida para vacas leiteiras. Diariamente, as silagens foram retiradas e fornecidas imediatamente (Fresca) ou após 48 horas de exposição (Exposta). Vinte vacas Holandesas foram distribuídas em 5 quadrados latinos replicados 4×4, com períodos de 21 dias (15 d para adaptação + 6 d para amostragem). As dietas foram formuladas para conter: 53% silagem de milho, 8% caroço de algodão, 18% farelo de soja, 9,5% polpa cítrica, 9% milho seco moído e 2,5% premix vitamínico e mineral. Os quatro tratamentos foram assim constituídos: silagem controle fresca (CF), silagem controle exposta (CE), silagem inoculada com levedura fresca (LF) e silagem inoculada com levedura exposta (LE). A inoculação com levedura aumentou as perdas de matéria seca (P<0,001) e reduziu o tempo de estabilidade aeróbia (P=0,03) das silagens de milho. No ensaio de desempenho animal, reduziu a produção de leite corrigida para 3,5% de gordura (P=0,03) e a eficiência alimentar (ELL leite/CMS) (P<0,01), porém não alterou o teor de gordura do leite. Quanto aos efeitos da exposição ao ar por 48 horas, estes reduziram a concentração de ácido lático (P<0,001), que consequentemente aumentou o pH (P=0,004) das silagens, além de reduzir outros produtos de fermentação. A exposição também reduziu a produção de leite corrigido para gordura (P=0,02) e a eficiência alimentar (P=0,10). Nenhum tratamento alterou o consumo de MS. Houve tendência para redução da digestibilidade da MS e FDN e do NDT, quando as silagens foram expostas ao ar. A inoculação com leveduras e a exposição ao ar por 48 horas deprimem o desempenho animal através da redução no valor nutritivo das silagens de milho.

Poesías.

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English language learners and standardized testing in an urban senior high school

The primary purpose of this study was to examine the influences of literacy variables on high-stakes test performance including: (a) student achievement on the Metropolitan Achievement Test, Seventh Edition (MAT-7) as correlated to the high-stakes test such as the FCAT examination and (b) the English language proficiency attained by English Language Learners (ELL) students when participating in, or exiting from English Speakers of Other Languages (ESOL) program as determined by the Limited English Proficient (LEP) committee. ^ Two one-sample Chi-square tests were conducted to investigate the relationship between passing the MAT-7 Reading and Language examinations and the FCAT-SSS Reading Comprehension and FCAT-NRT examinations. In addition, 2x2 Analyses of Variance (ANOVAs) were conducted to address the relationship between the time ELL students spent in the ESOL program and the level of achievement on MAT-7 Reading and Language examinations and the FCAT-SSS Reading Comprehension and FCAT-NRT. ^ Findings of this study indicated that more ELL students exit the program based on the LEP committee decisions than by passing the MAT-7. The majority of ELL students failed the 10th grade FCAT, the passing of which is needed for graduation. A significant number of ELL students failed, even when passing the MAT-7 or being duly exited through the decision of the LEP committee. The data also indicated that ELL students who exited the ESOL program in six semesters or fewer had higher FCAT scores than those who exited the program in seven semesters or more. The MAT-7 and the decision of the LEP committee were shown to be ineffective as predictors of success on the FCAT. ^ Further research to determine the length of time a student in the ESOL program uses English to read, write, and speak should be conducted. Additionally, the development of a new assessment instrument to better predict student success should be considered. However, it should be noted that the results of this study are limited to the context in which it was conducted and does not warrant generalizations beyond that context. ^

Language learning strategy use by colombian adult English language learners: A phenomenological study

The purpose of this phenomenological study was to describe how Colombian adult English language learners (ELL) select and use language learning strategies (LLS). This study used Oxford’s (1990a) taxonomy for LLS as its theoretical framework. Semi-structured interviews and a focus group interview, were conducted, transcribed, and analyzed for 12 Colombian adult ELL. A communicative activity known as strip story (Gibson, 1975) was used to elicit participants’ use of LLS. This activity preceded the focus group session. Additionally, participants’ reflective journals were collected and analyzed. Data were analyzed using inductive, deductive, and comparative analyses. Four themes emerged from the inductive analysis of the data: (a) learning conditions, (b) problem-solving resources, (c) information processing, and (d) target language practice. Oxford’s classification of LLS was used as a guide in deductively analyzing data concerning the participants’ experiences. The deductive analysis revealed that participants do not use certain strategies included in Oxford’s taxonomy at the third level. For example, semantic mapping, or physical response or sensation was not reported by participants. The findings from the inductive and deductive analyses were then compared to look for patterns and answers to the research questions. The comparative analysis revealed that participants used additional LLS that are not included in Oxford’s taxonomy. Some examples of these strategies are: using sound transcription in native language and help from children. The study was conducted at the MDC InterAmerican campus in South Florida, one of the largest Hispanic-influenced communities in the U.S. Based on the findings from this study, the researcher proposed a framework to study LLS that includes both external (i.e., learning context, community) and internal (i.e., culture, prior education) factors that influence the selection and use of LLS. The findings from this study imply that given the importance of the both external and internal factors in learners’ use of LLS, these factors should be considered for inclusion in any study of language learner strategies use by adult learners. Implications for teaching and learning as well as recommendations for further research are provided.

A comparison of the effects of classroom and Multi-User Virtual Environments on the perceived speaking anxiety of adult post-secondary English Language Learners

The population of English Language Learners (ELLs) globally has been increasing substantially every year. In the United States alone, adult ELLs are the fastest growing portion of learners in adult education programs (Yang, 2005). There is a significant need to improve the teaching of English to ELLs in the United States and other English-speaking dominant countries. However, for many ELLs, speaking, especially to Native English Speakers (NESs), causes considerable language anxiety, which in turn plays a vital role in hindering their language development and academic progress (Pichette, 2009; Woodrow, 2006). ^ Task-based Language Teaching (TBLT), such as simulation activities, has long been viewed as an effective approach for second-language development. The current advances in technology and rapid emergence of Multi-User Virtual Environments (MUVEs) have provided an opportunity for educators to consider conducting simulations online for ELLs to practice speaking English to NESs. Yet to date, empirical research on the effects of MUVEs on ELLs' language development and speaking is limited (Garcia-Ruiz, Edwards, & Aquino-Santos, 2007). ^ This study used a true experimental treatment control group repeated measures design to compare the perceived speaking anxiety levels (as measured by an anxiety scale administered per simulation activity) of 11 ELLs (5 in the control group, 6 in the experimental group) when speaking to Native English Speakers (NESs) during 10 simulation activities. Simulations in the control group were done face-to-face, while those in the experimental group were done in the MUVE of Second Life. ^ The results of the repeated measures ANOVA revealed after the Huynh-Feldt epsilon correction, demonstrated for both groups a significant decrease in anxiety levels over time from the first simulation to the tenth and final simulation. When comparing the two groups, the results revealed a statistically significant difference, with the experimental group demonstrating a greater anxiety reduction. These results suggests that language instructors should consider including face-to-face and MUVE simulations with ELLs paired with NESs as part of their language instruction. Future investigations should investigate the use of other multi-user virtual environments and/or measure other dimensions of the ELL/NES interactions.^