Getting a Grip on Memory: Unilateral Hand Clenching Alters Episodic Recall

Unilateral hand clenching increases neuronal activity in the frontal lobe of the contralateral hemisphere. Such hand clenching is also associated with increased experiencing a given hemisphere’s “mode of processing.” Together, these findings suggest that unilateral hand clenching can be used to test hypotheses concerning the specializations of the cerebral hemispheres during memory encoding and retrieval. We investigated this possibility by testing the effects of a unilateral hand clenching on episodic memory. The hemispheric Encoding/Retrieval Asymmetry (HERA) model proposes left prefrontal regions are associated with encoding, and right prefrontal regions with retrieval, of episodic memories. It was hypothesized that right-hand clenching (left hemisphere activation) pre-encoding, and left-hand clenching (right hemisphere activation) pre-recall, would result in superior memory. Results supported the HERA model. Also supported was that simple unilateral hand clenching can be used as a means by which the functional specializations of the cerebral hemispheres can be investigated in intact humans

Scanning Laser Acoustic Microscope Visualization of Solid Inclusions in Silicon Nitride

The Scanning Laser Acoustic Microscope (SLAM) operating at a frequency of 100 MHz is used to characterize solid inclusions in silicon nitride. Ten, seven millimeter thick discs, with 100 and 400 micron implanted inclusions are analyzed. We find that the images of a solid inclusion are characterized by a bright high transmission central zone, a well defined dark boundary and a characteristic diffraction ring pattern. These image features differentiate solid inclusions from pores and voids which may also be encountered in the samples. The images of the implanted flaws were generally found to be larger than anticipated. This can be understood in terms of the divergence of the sound due to diffraction and due to lens action of the curved boundary of the flaw. Our initial observations suggest that accurate estimates of defect size may be obtaiRable from a more complete analysis of SLAM micrographs

Differentiation of Various Flaw Types in Ceramics Using the Scanning Laser Acoustic Microscope

High frequency acoustic imaging represents a powerful technique for the nondestructive evaluation of optically opaque materials. In this report the Scanning Laser Acoustic Microscope (SLAM) is used to detect and characterize flaws in ceramics. SLAM micrographs showing typical examples of cracks, laminar flaws, porosity and solid inclusions. are presented. The various flaw types are easily differentiated on the basis of their characteristic acoustic signatures. The importance of an imaging approach to the nondestructive evaluation of ceramics is demonstrated

Strength, But Not Direction, of Handedness Is Related to Height

Left-handers are reputed to be shorter than right-handers. However, previous research has confounded handedness direction (left- versus right-handedness) with handedness strength (consistency with which one hand is chosen across a variety of tasks; consistent- versus inconsistent-handedness). Here, we support a relationship between handedness strength, but not direction, and stature, with increasing inconsistent-handedness associated with increasing self-reported height

Collaborative multidisciplinary learning : quantity surveying students’ perspectives

The construction industry is highly fragmented and is known for its adversarial culture, culminating in poor quality projects not completed on time or within budget. The aim of this study is thus to guide the design of QS programme curricula in order to help students develop the requisite knowledge and skills to work more collaboratively in their multi-disciplinary future workplaces. A qualitative approach was considered appropriate as the authors were concerned with gathering an initial understanding of what students think of multi-disciplinary learning. The data collection method used was a questionnaire which was developed by the Behaviours4Collaboration (B4C) team. Knowledge gaps were still found across all the key areas where a future QS practitioner needs to be collaborative (either as a project contributor or as a project leader) despite the need for change instigated by the multi-disciplinary (BIM) education revolution. The study concludes that universities will need to be selective in teaching, and innovative in reorienting, QS education so that a collaborative BIM education can be effected in stages, increasing in complexity as the students’ technical knowledge grows. This will help students to build the competencies needed to make them future leaders. It will also support programme currency and delivery

Fusion of simian immunodeficiency virus with liposomes and erythrocyte ghost membranes: Effects of lipid composition, pH and calcium

Simian immunodeficiency virus from macaques (SIV(mac)) is closely related in its structure and biological activity to human immunodeficiency virus, and is the best animal model for the acquired immunodeficiency syndrome. We investigated the kinetics of membrane fusion between SIV(mac) and phospholipid vesicles and the effects of various parameters on this process. Purified SIV(mac) was labelled with octadecyl rhodamine B chloride, and fusion was continuously monitored as the dilution of the probe in target membranes. These studies show that SIV(mac) fusion is strongly dependent upon the liposome composition. Fusion with pure cardiolipin (CL) liposomes is significantly faster than with CL/dioleoylphosphatidylcholine (DOPC) (3 : 7), phosphatidylserine (PS) or disialoganglioside (G(D1a))/DOPC (1.5 : 8.5) vesicles. SIV(mac) does not fuse appreciably with pure DOPC liposomes. Reduction of pH from 7.5 to 4.5 greatly enhances the rate of SIV(mac) fusion with CL, CL/DOPC and PS membranes, but does not affect fusion with DOPC or G(D1a)/DOPC membranes. Calcium stimulates viral fusion with CL liposomes, but not with CL/DOPC or DOPC liposomes. SIV(mac) fuses with human erythrocyte ghost membranes only slowly at reduced pH. Our results indicate that SIV(mac) can fuse with membranes lacking the known viral receptor, CD4. Although the mechanism of SIV(mac) fusion with model and biological membranes remains to be determined, the fusion activity of SIV(mac) shares similarities with other lipid-enveloped viruses such as Sendai and influenza viruses

High refractive index of melanin in shiny occipital feathers of a bird of paradise

Male Lawes's Parotia, a bird of paradise, use the highly directional reflection of the structurally colored, brilliant-silvery occipital feathers in their courtship display. As in other birds, the structural coloration is produced by ordered melanin pigmentation. The barbules of the Parotia's occipital feathers, with thickness ~3 µm, contain 6–7 layers of densely packed melanin rodlets (diameter ~0.25 µm, length ~2 µm). The effectively ~0.2 µm thick melanin layers separated by ~0.2 µm thick keratin layers create a multilayer interference reflector. Reflectance measurements yielded peak wavelengths in the near-infrared at ~1.3 µm, i.e., far outside the visible wavelength range. With the Jamin-Lebedeff interference microscopy method recently developed for pigmented media, we here determined the refractive index of the intact barbules. We thus derived the wavelength dependence of the refractive index of the barbules' melanin to be 1.7–1.8 in the visible wavelength range. Implementing the anatomical and refractive index data in an optical multilayer model, we calculated the barbules' reflectance, transmittance and absorptance spectra, thereby confirming measured spectra

All-Sky spectrally matched UBVRI-ZY and u'g'r'i'z' magnitudes for stars in the Tycho2 catalog

We present fitted UBVRI-ZY and u'g'r'i'z' magnitudes, spectral types and distances for 2.4M stars, derived from synthetic photometry of a library spectrum that best matches the Tycho2 BtVt, NOMAD Rn and 2MASS JHK_{2/S} catalog magnitudes. We present similarly synthesized multi-filter magnitudes, types and distances for 4.8M stars with 2MASS and SDSS photometry to g<16 within the Sloan survey region, for Landolt and Sloan primary standards, and for Sloan Northern (PT) and Southern secondary standards. The synthetic magnitude zeropoints for BtVt, UBVRI, ZvYv, JHK_{2/S}, JHK_{MKO}, Stromgren uvby, Sloan u'g'r'i'z' and ugriz are calibrated on 20 calspec spectrophotometric standards. The UBVRI and ugriz zeropoints have dispersions of 1--3%, for standards covering a range of color from -0.3 < V-I < 4.6; those for other filters are in the range 2--5%. The spectrally matched fits to Tycho2 stars provide estimated 1-sigma errors per star of ~0.2, 0.15, 0.12, 0.10 and 0.08 mags respectively in either UBVRI or u'g'r'i'z'; those for at least 70% of the SDSS survey region to g<16 have estimated 1-sigma errors per star of ~0.2, 0.06, 0.04, 0.04, 0.05 in u'g'r'i'z' or UBVRI. The density of Tycho2 stars, averaging about 60 stars per square degree, provides sufficient stars to enable automatic flux calibrations for most digital images with fields of view of 0.5 degree or more. Using several such standards per field, automatic flux calibration can be achieved to a few percent in any filter, at any airmass, in most workable observing conditions, to facilitate inter-comparison of data from different sites, telescopes and instruments.Comment: 36 pages, 30 figures, 3 printed tables, several electronic tables, accepted PASP Dec 201