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Recent studies indicate that membrane cholesterol can associate with G protein-coupled receptors (GPCRs) and affect their function. Previously, we reported that manipulation of membrane cholesterol affects ligand binding and signal transduction of the type 1 cholecystokinin receptor (CCK1R), a Class A GPCR. We now demonstrate that the closely related type 2 cholecystokinin receptor (CCK2R) does not share this cholesterol sensitivity. The sequences of both receptors reveal almost identical cholesterol interaction motifs in analogous locations in transmembrane segments two, three, four, and five. The disparity in cholesterol sensitivity between these receptors, despite their close structural relationship, provides a unique opportunity to define the possible structural basis of cholesterol sensitivity of CCK1R. To evaluate the relative contributions of different regions of CCK1R to cholesterol sensitivity, we performed ligand binding studies and biological activity assays of wild-type and CCK2R/CCK1R chimeric receptor-bearing Chinese hamster ovary cells after manipulation of membrane cholesterol. We also extended these studies to site-directed mutations within the cholesterol interaction motifs. The results contribute to a better understanding of the structural requirements for cholesterol sensitivity in CCK1R and provides insight into the function of other cholesterol-sensitive Class A GPCRs.

The correct name for the Cuban species of Trichospermum Bl. (Malvaceae: Grewioideae) also found in Mexico and Central America is T. lessertianum (Hochr.) Dorr, comb. n. The name T. mexicanum (DC.) Baill., incorrectly applied to this Cuban species, should be restricted to a species endemic to western and southern Mexico.

Nesogordonia tricarpellata Skema & Dorr, sp. nov., a new species from southeastern Madagascar, is described and illustrated. It differs from all other species of Nesogordonia Baill. in6–9 stamens, 3 staminodes, a 3-carpellate ovary, and a 3-valved capsule. These androecial and gynoecial characters require modification of the long-standing circumscription of the genus. This new species also has the southernmost geographic range of any species in the genus.

We have previously demonstrated that high concentrations of nerve growth factor suppress neurite outgrowth from sensory neurons. Inhibition could be mediated by either the p75NTR or TrkA receptor. We used a functional block of p75NTR by REX antibody in rat dorsal root ganglion neurons and dorsal root ganglion cultures from p75NTR knockout mice. In both systems, high-dose NGF inhibited neurite outgrowth, implying that p75NTR is not involved in suppression of neurite outgrowth. Confocal images of dissociated dorsal root ganglion neurons exposed to fluorescence-tagged NGF showed ligand internalization. Radioligand binding indicated disappearance of high-affinity binding sites from the surface of dorsal root ganglia after treatment with 200 ng/ml NGF for 1 h. Downstream signaling showed sustained hyperphosphorylation of MAPK (Erk1–2) but not of SNT or Akt. High-dose NGF may induce cytoplasmic relocation of the receptor TrkA and axonal growth arrest independently of p75NTR.

Cation-disordered rock-salt cathodes (DRX) are promising materials that could deliver high capacities (>250 mAh g-1) with Earth abundant elements and materials. However, their electrochemical performances, other than the capacity, should be improved to be competitive cathodes, and many strategies have been introduced to enhance DRXs. Fluorination has been shown to inhibit oxygen loss and increase power density. Nevertheless, fluorinated cation-disordered rock-salts still suffer from rapid material deterioration and low scalability which limit their practical applications. This mini-review highlights the key challenges for the commercialization of fluorinated cation-disordered rock-salts, discusses the underlying reasons behind material failure and proposes future development directions.

Human papillomaviruses (HPV) are detected in 70–80% of oropharyngeal cancers in the developed world, the incidence of which has reached epidemic proportions. The current paradigm regarding the status of the viral genome in these cancers is that there are three situations: one where the viral genome remains episomal, one where the viral genome integrates into the host genome and a third where there is a mixture of both integrated and episomal HPV genomes. Our recent work suggests that this third category has been mischaracterized as having integrated HPV genomes; evidence indicates that this category consists of virus–human hybrid episomes. Most of these hybrid episomes are consistent with being maintained by replication from HPV origin. We discuss our evidence to support this new paradigm, how such genomes can arise, and more importantly the implications for the clinical management of HPV positive head and neck cancers following accurate determination of the viral genome status.

In this position paper, we introduce the concept of socioscientific capital (SSC) to denote students' resources that unequivocally play a part when students learn about and make decisions regarding socioscientific issues (SSIs). Students use a variety of resources when they engage with SSI. Our conceptualization of SSC expands on current conceptualizations to refer to resources related to both the scientific and the non-scientific aspects of SSI, including internal resources (personal experiences, values, attitudes, beliefs, knowledge, and skills), external resources (family, friends, communities, and media), and meta-level resources (dominant frames and cultures). Aiming to strengthen SSI education, we argue for taking into account how students' resources impact their SSI-related learning and decision-making. To this end, insight into students' SSC is needed and is imperative for teachers. By bringing together literature about SSI education and literature about students' resources, we provide a conceptual view on students' SSC and describe implications for SSI education.

The current study is about students' engagement with socioscientific issues (SSI). We explored the use of sources of knowledge about SSI and attitudes toward SSI among a sample of 1676 Dutch 8- to 16-year-old students. First, we developed a questionnaire that measured students' use of four sources of knowledge about SSI: Social Resources (online media use and talking with parents and friends), In-Class Resources (in-class talk and in-class offline media use), Visit Resources (visiting the zoo or a science museum with parents or school), and Offline Media Resources (engaging with issues or the news via books, magazines, newspapers, or TV). Second, we performed a latent profile analysis to explore students' patterns of use of these sources. This resulted in five profiles: Social Visitors (5.9%), Offline Media Consumers (10.6%), Media Discussers (14.3%), In-Class Users (21.0%), and Non-Users (48.3%). Third, we related these profiles to students' attitudes toward SSI, as measured with the Pupils' Attitudes toward Socioscientific Issues (PASSI) questionnaire. In line with the sources of knowledge profiles, the Non-Users felt and thought most negatively about engagement with SSI, while the Media Discussers showed the most positive attitudes. We believe that our exploration of the profiles adds to the discourse about students' socioscientific capital. Moreover, this study informs teachers about the resources that students may bring into the learning environment and their decision-making about SSI. The study concludes with practical suggestions about stimulating the use of sources of knowledge for certain groups of students and fostering positive attitudes toward engagement with SSI.

This report describes the first pathologic and immunohistochemical recognition in Australia of a rabies-like disease in a native mammal, a fruit bat, the black flying fox (Pteropus alecto). A virus with close serologic and genetic relationships to members of the Lyssavirus genus of the family Rhabdoviridae was isolated in mice from the tissue homogenates of a sick juvenile animal.

We present the unusual case of a 74 year-old female with a history of breast cancer who presented with acute painless orbital swelling and vertical diplopia. MRI revealed a focal enhancing mass within the superior rectus muscle. As the concern for metastatic disease was high, surgical biopsy was performed and revealed an unusual mimicker of metastatic disease, the parasitic infection dirofilariasis.

Guided Lamb waves are commonly used in nondestructive evaluation to monitor plate-like structures or to characterize properties of composite or layered materials. However, the dispersive propagation and multimode excitability of Lamb waves complicate their analysis. Advanced signal processing techniques are therefore required to resolve both the time and frequency content of the time-domain wave signals. The chirplet transform (CT) has been introduced as a generalized time-frequency representation (TFR) incorporating more flexibility to adjust the window function to the group delay of the signal when compared to the more classical short-time Fourier transform (STFT). Exploiting this additional degree of freedom, this paper applies an adaptive algorithm based on the CT to calculate mode displacement ratios and attenuation of Lamb waves in elastic plate structures. The CT-based algorithm has a clear performance advantage when calculating mode displacement ratios and attenuation for numerically-simulated Lamb wave signals. For experimental data, the CT retains an advantage over the STFT although measurement noise and parameter uncertainties lead to larger overall deviations from the theoretically expected solutions.