Who's the Boss? How Communicative Competence Is Defined in a Multilingual Preschool Classroom

This article investigates how classroom communicative competence was defined in a multilingual preschool classroom. Sociolinguistic analysis of a conflict event, and the larger classroom context, reveals the norms and values that influenced the behaviors of an English-speaking teacher, bilingual teaching assistant, and two Chinese-speaking preschoolers. The article identifies problems that teachers face when they attempt to value the children's home languages at the same time that they socialize them into U.S. English-speaking classrooms.     

Possible antiestrogenic activity of lindane in female rats

During chronic peroral (PO) treatment of weanling, female Fischer 344 rats with daily injections (0.069 mmol/kg) of either 1,1′-(2,2,2-trichloroethylidene) bis [4-chlorobenzene] (p,p′-DDT), 2,4-dichlorophenoxy acetic acid (2,4-D), or γ-hexachlorocyclohexane (lindane), the lindane treatment induced a significant 20% increase in body weight after 110 days. Further investigation with 0,5,10,20, and 40 mg/kg lindane confirmed a significant increase in average body weight gain at the two highest doses after ten weeks of treatment. Significantly greater food consumption was observed, and the Lee index indicated that lindane treatment induced obesity. In addition to obesity, lindane caused a delay in vaginal opening, disrupted estrous cycling, reduced pituitary and uterine weight, and elevated food consumption during proestrus (when appetite is normally suppressed by estradiol). These responses suggest that, by inducing alterations in the reproductive function of the female rat and by interfering with hormonal regulation of energy balance, lindane may be antiestrogenic rather than estrogenic as previously proposed.     

Exploring the oxidation and iron binding profile of a cyclodextrin encapsulated quercetin complex unveiled a controlled complex dissociation through a chemical stimulus

Background

Flavonoids possess a rich polypharmacological profile and their biological role is linked to their oxidation state protecting DNA from oxidative stress damage. However, their bioavailability is hampered due to their poor aqueous solubility. This can be surpassed through encapsulation to supramolecular carriers as cyclodextrin (CD). A quercetin- 2HP-β-CD complex has been formerly reported by us. However, once the flavonoid is in its 2HP-β-CD encapsulated state its oxidation potential, its decomplexation mechanism, its potential to protect DNA damage from oxidative stress remained elusive. To unveil this, an array of biophysical techniques was used.

Long-Lived Folding Intermediates Predominate the Targeting-Competent Secretome

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Environmental Sequencing Fills the Gap Between Parasitic Haplosporidians and Free‐living Giant Amoebae

Class Ascetosporea (Rhizaria; Endomyxa) comprises many parasites of invertebrates. Within this group, recent group‐specific environmental DNA (eDNA) studies have contributed to the establishment of the new order Mikrocytida, a new phylogeny and characterization of Paramyxida, and illuminated the diversity and distribution of haplosporidians. Here, we use general and lineage‐specific PCR primers to investigate the phylogenetic “gap” between haplosporidians and their closest known free‐living relatives, the testate amoeba Gromia and reticulate amoeba Filoreta. Within this gap are Paradinium spp. parasites of copepods, which we show to be highly diverse and widely distributed in planktonic and benthic samples. We reveal a robustly supported radiation of parasites, ENDO‐3, comprised of Paradinium and three further clades (ENDO‐3a, ENDO‐3b and SPP). A further environmental group, ENDO‐2, perhaps comprising several clades, branches between this radiation and the free‐living amoebae. Early diverging haplosporidians were also amplified, often associated with bivalves or deep‐sea samples. The general primer approach amplified an overlapping set of novel lineages within ENDO‐3 and Haplosporida, whereas the group‐specific primer strategy, targeted to amplify from the earliest known divergent haplosporidians to Gromia, generated greater sequence diversity across part of this phylogenetic range.     

Cellular Senescence Is Induced by the Environmental Neurotoxin Paraquat and Contributes to Neuropathology Linked to Parkinson’s Disease

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The thermal dependency of locomotor performance evolves rapidly within an invasive species

Biological invasions can stimulate rapid shifts in organismal performance, via both plasticity and adaptation. We can distinguish between these two proximate mechanisms by rearing offspring from populations under identical conditions and measuring their locomotor abilities in standardized trials. We collected adult cane toads (Rhinella marina) from invasive populations that inhabit regions of Australia with different climatic conditions. We bred those toads and raised their offspring under common‐garden conditions before testing their locomotor performance. At high (but not low) temperatures, offspring of individuals from a hotter location (northwestern Australia) outperformed offspring of conspecifics from a cooler location (northeastern Australia). This disparity indicates that, within less than 100 years, thermal performance in cane toads has adapted to the novel abiotic challenges that cane toads have encountered during their invasion of tropical Australia.     

Primary human muscle satellite cell culture: Variations of cell yield,proliferation and differentiation rates according to age and sex of donors,site of muscle biopsy,and delay before processing

The present study was performed to determine the influence on human satellite cell yield, proliferation, and differentiation rates of: 1) sex and age of donors; 2) site of the muscle biopsy; and 3) delay before processing of the muscle biopsy sample. We used a standardized primary muscle cell culture procedure on 206 normal muscle samples obtained from different muscle groups of patients aged from 20 to 88 years, at time of orthopedic surgery. Sex of donors did not influence muscle culture parameters. In contrast, aging tended to affect muscle cell yield (age group 50–59 years vs 70–79 years, P < 0.08), but not myogenic cell abilities to proliferate and to fuse into myotubes. The anatomic origin of muscle samples used for culture appeared to influence culture parameters. In contrast with other tested muscles, the tensor fasciae muscle gave both a good cell yield (174 ± 25 10³ cells per gram) and homogeneous proliferation and differentiation rates. Storage of the muscle sample at 4°C in transport medium was associated with a very high cell yield when processing was done in early hours after biopsy (277 ± 50 10³ cells/g), a high and stable cell yield when processing was done from day 1 to day 3 after biopsy (185 ± 15 10³ cells/g), and a poor cell yield when processing was done after day 4 (111 ± 13 10³ cells/g). Storage of muscle biopsy samples at 4°C for 1 to 4 days was associated with good proliferation and fusion rates. In conclusion, these data validate a convenient procedure of primary human muscle cell culture, using tensor fasciae muscle biopsy, which is easily done at time of orthopedic surgery, obtained from men and women of all ages (if possible less than 70 years to obtain good cell yield), and allowing of 1–3 days of storage before processing that may compensate uncertainty of the exact time of availability of muscle samples for the scientist.     

Tr-Noe and MD studies of Leishmania gp63 SRYD-containing sequences bound to anti-SRYD monoclonal antibody

The I²⁵⁰ASRYDQL²⁵⁷ synthetic octapeptideof the Leishmania major surface glycoproteingp63, which efficiently inhibits parasite attachmentto the macrophage receptors and mimics antigenicallyand functionally the RGDS sequence of fibronectin, wasstudied by 2D TR-NOESY in the presence of an anti-SRYDmonoclonal antibody (mAbSRYD) that recognizes bothSRYD-containing peptides and the cognate protein onintact parasites. Molecular modeling was performedusing distance constraints obtained from TR-NOEs. Thebound structure was compared with that of the freepeptide in DMSO solution and with the crystalstructure of the RYD fragment of the OPG2 Fab, anantireceptor antibody that mimics an RGD cell adhesion site.