What informs the process of remembering and forgetting? Is it merely about our capability to store and retrieve experiences in a purely functional sense? What about ′collective memories′, not just ...those of the individual - how do these manifest themselves in the passages of time? The authors present a new, fascinating insight into the social psychology of experience drawing upon a number of classic works (particularly by Frederick Bartlett, Maurice Halbwachs & Henri Bergson) to help develop their argument. The significance of their ideas for developing a contemporary psychology of experience is illustrated with material from studies focused on settings at home and at work, in public and commercial organizations where remembering and forgetting are matters of concern, involving language and text based communication, objects and place. As their argument unfolds, the authors reveal that memories do not solely reside in a linear passage of time, linking past, present and future, nor do they soley rest within the indidvidual′s conciousness, but that memory sits at the very heart of ′lived experience′; whether collective or individual, the vehicle for how we remember or forget is linked to social interaction, object interaction and the different durations of living that we all have. It is very much connected to the social psychology of experience.
The accuracy of clinical communication in referrals to dermatology has not been fully explored. Baseline analysis of inpatient ward referral to a dermatology service revealed that only 37% of ...referrals used accurate descriptive terminology. Theme analysis of individual descriptive terms used was performed to assess knowledge deficits and develop a novel intervention to improve descriptive accuracy. A descriptive algorithm was developed to act as a scaffolding resource for the use of descriptive terms. The Belfast Dermatology Descriptive Algorithm was developed as a tool to determine primary and secondary morphological features of eruptions, and to highlight common clinical pitfalls. It was designed to adhere to principles of adult learning. Assessment was completed following the introduction of the algorithm. The accuracy of descriptions used was increased to 70% with the introduction of the resource. This outcome reflects how educational interventions, in the format of an accessible resource tool, can be used as a unique intervention to improve education in clinical practice.
The biological function of high-density lipoprotein (HDL) nanoparticles, the so-called good cholesterol that is associated with a low risk of heart disease, depends on their composition, morphology, ...and size. The morphology of HDL particles composed of apolipoproteins, lipids and cholesterol is routinely visualised by transmission electron microscopy (TEM), but higher-resolution tools are needed to observe more subtle structural differences between particles of different composition. Here, reconstituted HDL formulations are oriented on glass substrates and solid-state
P NMR spectroscopy is shown to be highly sensitive to the surface curvature of the lipid headgroups. The spectra report potentially functionally important differences in the morphology of different HDL preparations that are not detected by TEM. This method provides new morphological insights into HDL comprising a naturally occurring apolipoprotein A-I mutant, which may be linked to its atheroprotective properties, and holds promise as a future research tool in the clinical analysis of plasma HDL.
The biological function of high‐density lipoprotein (HDL) nanoparticles, the so‐called good cholesterol that is associated with a low risk of heart disease, depends on their composition, morphology, ...and size. The morphology of HDL particles composed of apolipoproteins, lipids and cholesterol is routinely visualised by transmission electron microscopy (TEM), but higher‐resolution tools are needed to observe more subtle structural differences between particles of different composition. Here, reconstituted HDL formulations are oriented on glass substrates and solid‐state 31P NMR spectroscopy is shown to be highly sensitive to the surface curvature of the lipid headgroups. The spectra report potentially functionally important differences in the morphology of different HDL preparations that are not detected by TEM. This method provides new morphological insights into HDL comprising a naturally occurring apolipoprotein A‐I mutant, which may be linked to its atheroprotective properties, and holds promise as a future research tool in the clinical analysis of plasma HDL.
31P NMR spectra are highly sensitive to the morphology of high‐density lipoprotein nanoparticles when oriented on glass surfaces. The spectra reveal new molecular insights that are relevant to the protective function of the lipoprotein nanoparticles against cardiovascular disease.
It has been shown extensively that glycosaminoglycan (GAG)-protein interactions can induce, accelerate, and impede the clearance of amyloid fibrils associated with systemic and localized amyloidosis. ...Obtaining molecular details of these interactions is fundamental to our understanding of amyloid disease. Consequently, there is a need for analytical approaches that can identify protein conformational transitions and simultaneously characterize heparin interactions. By combining Raman spectroscopy with two-dimensional (2D) perturbation correlation moving window (2DPCMW) analysis, we have successfully identified changes in protein secondary structure during pH- and heparin-induced fibril formation of apolipoprotein A-I (apoA-I) associated with atherosclerosis. Furthermore, from the 2DPCMW, we have identified peak shifts and intensity variations in Raman peaks arising from different heparan sulfate moieties, indicating that protein-heparin interactions vary at different heparin concentrations. Raman spectroscopy thus reveals new mechanistic insights into the role of GAGs during amyloid fibril formation.
Structures of membrane proteins determined by X-ray crystallography and, increasingly, by cryo-electron microscopy often fail to resolve the structural details of unstable or reactive small molecular ...ligands in their physiological sites. This work demonstrates that
13
C chemical shifts measured by magic-angle spinning (MAS) solid-state NMR (SSNMR) provide unique information on the conformation of a labile ligand in the physiological site of a functional protein in its native membrane, by exploiting freeze-trapping to stabilise the complex. We examine the ribose conformation of ATP in a high affinity complex with Na,K-ATPase (NKA), an enzyme that rapidly hydrolyses ATP to ADP and inorganic phosphate under physiological conditions. The
13
C SSNMR spectrum of the frozen complex exhibits peaks from all ATP ribose carbon sites and some adenine base carbons. Comparison of experimental chemical shifts with density functional theory (DFT) calculations of ATP in different conformations and protein environments reveals that the ATP ribose ring adopts an C3′-
endo
(N) conformation when bound with high affinity to NKA in the E
1
Na state, in contrast to the C2′-
endo
(S) ribose conformations of ATP bound to the E2P state and AMPPCP in the E1 complex. Additional dipolar coupling-mediated measurements of H-C-C-H torsional angles are used to eliminate possible relative orientations of the ribose and adenine rings. The utilization of chemical shifts to determine membrane protein ligand conformations has been underexploited to date and here we demonstrate this approach to be a powerful tool for resolving the fine details of ligand-protein interactions.
Solid-state NMR and DFT
13
C chemical shift calculations are used to determine the ribose ring conformation of hydrolysable adenosine 5′-triphosphate when freeze-trapped in the high-affinity binding site of Na,K-ATPase.
A pathological signature of Alzheimer's disease (AD) is the formation of neurofibrillary tangles comprising filamentous aggregates of the microtubule associated protein tau. Tau self-assembly is ...accelerated by polyanions including heparin, an analogue of heparan sulfate. Tau filaments colocalize with heparan sulfate proteoglycans (HSPGs) in vivo, and HSPGs may also assist the transcellular propagation of tau aggregates. Here, we investigate the role of the sulfate moieties of heparin in the aggregation of a recombinant tau fragment Δtau187, comprising residues 255-441 of the C-terminal microtubule-binding domain. The effects that the selective removal of the
-, 2-
-, and 6-
-sulfate groups from heparin have on the kinetics of tau aggregation, aggregate morphology, and protein structure and dynamics were examined. Aggregation kinetics monitored by thioflavin T (ThT) fluorescence revealed that aggregation is considerably slower in the presence of 2-
-desulfated heparin than with
- or 6-
-desulfated heparin. Transmission electron microscopy revealed that tau filaments induced by 2-
-desulfated heparin were more slender than filaments formed in the presence of intact heparin or 6-
-desulfated heparin. The 2-
-desulfated heparin-induced filaments had more extensive regions of flexibility than the other filaments, according to circular dichroism and solid-state NMR spectroscopy. These results indicate that the sulfation pattern of heparin regulates tau aggregation, not purely though electrostatic forces but also through conformational perturbations of heparin when the 2-
-sulfate is removed. These findings may have implications for the progression of AD, as the sulfation pattern of GAGs is known to change during the aging process, which is the main risk factor for the disease.
New Guinea is the world's largest tropical island and has fascinated naturalists for centuries1,2. Home to some ofthe best-preserved ecosystems on the planet3 and to intact ecological gradients-from ...mangroves to tropical alpine grasslands-that are unmatched in the Asia-Pacific region4,5, it is a globally recognized centre of biological and cultural diversity6,7. So far, however, there has been no attempt to critically catalogue the entire vascular plant diversity of New Guinea. Here we present the first, to our knowledge, expert-verified checklist of the vascular plants of mainland New Guinea and surrounding islands. Our publicly available checklist includes 13,634 species (68% endemic), 1,742 genera and 264 families-suggesting that New Guinea is the most floristically diverse island in the world. Expert knowledge is essential for building checklists in the digital era: reliance on online taxonomic resources alone would have inflated species counts by 22%. Species discovery shows no sign of levelling off, and we discuss steps to accelerate botanical research in the 'Last Unknown'8.
Queuing up: Molecular orientation within macroscopically aligned nanotubes of the peptide AAAAAAK can be studied by solid‐state NMR and IR spectroscopy. Line shape analysis of the NMR spectra ...indicates that the peptide NH bonds are tilted 65–70° relative to the nanotube long axis. Re‐evaluation of earlier X‐ray fiber diffraction data suggests that the peptide molecules are hydrogen‐bonded in a helical arrangement along the nanotube axis.
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