Household Borrowing Constraints and Residential Investment Dynamics

Why does residential investment lead output in the US and Canada but it is coincident in other industrialized countries? In this paper we explore the role of home-equity loans used to boost consumption as a channel that affects residential investment. Towards this end, we consider a multi

Harnessing instability to control wave propagation in phononic crystals and acoustic metamaterials

Artificially structured composite materials have the ability to manipulate the propagation of elastic waves due to the existence of band gaps, i.e., frequency ranges of strong wave attenuation. However, most configurations proposed to date cannot be tuned after the manufacturing process. We propose new strategies using elastic buckling mechanisms to design novel devices with in-situ adaptive properties that can be reversibly tuned. Buckling and large deformations can be effectively exploited to reversibly tune not only the width and location of band gaps, but also the directional preferences of the wave propagation, even for low-frequency elastic waves. Our proof-of-concept demonstrations also indicate that the proposed mechanisms work robustly over a wide range of length scales, opening avenues for the design of smart systems for applications, such as vibration/noise reduction, wave guiding, frequency modulation, and acoustic imaging

Optimized measurements of separations and angles between intra-molecular fluorescent markers

We demonstrate a novel, yet simple tool for the study of structure and function of biomolecules by extending two-colour co-localization microscopy to fluorescent molecules with fixed orientations and in intra-molecular proximity. From each colour-separated microscope image in a time-lapse movie and using only simple means, we simultaneously determine both the relative (x,y)-separation of the fluorophores and their individual orientations in space with accuracy and precision. The positions and orientations of two domains of the same molecule are thus time-resolved. Using short double-stranded DNA molecules internally labelled with two fixed fluorophores, we demonstrate the accuracy and precision of our method using the known structure of double-stranded DNA as a benchmark, resolve 10-base-pair differences in fluorophore separations, and determine the unique 3D orientation of each DNA molecule, thereby establishing short, double-labelled DNA molecules as probes of 3D orientation of anything to which one can attach them firmly

Harmonic Force Spectroscopy measures load-dependent kinetics of individual human β-cardiac myosin molecules

International audienceMolecular motors are responsible for numerous cellular processes from cargo transport to heart contraction. Their interactions with other cellular components are often transient and exhibit kinetics that depend on load. Here, we measure such interactions using 'harmonic force spectroscopy'. In this method, harmonic oscillation of the sample stage of a laser trap immediately, automatically and randomly applies sinusoidally varying loads to a single motor molecule interacting with a single track along which it moves. The experimental protocol and the data analysis are simple, fast and efficient. The protocol accumulates statistics fast enough to deliver single-molecule results from single-molecule experiments. We demonstrate the method's performance by measuring the force-dependent kinetics of individual human b-cardiac myosin molecules interacting with an actin filament at physiological ATP concentration. We show that a molecule's ADP release rate depends exponentially on the applied load, in qualitative agreement with cardiac muscle, which contracts with a velocity inversely proportional to external load

Post Herpetic Neuropathy of Sinuvertebral Nerve: A Case Report

Varicella-Zoster virus is a neurotropic virus of the herpes virus family that primarily affects sensory nerves. Herpes zoster causing sinuvertebral neuropathy has not been mentioned in the literature. A 55 years old man presented with low back pain, both buttocks, posterior thigh and leg pain over last 3 months. A straight leg raising test was positive on both sides. A left great toe dorsiflexion was decreased to 4/5. The VAS score at admission for back and leg pain was 7/10. The patient MRI was showing disc degeneration at L5-S1 level. We performed endoscopic interlaminar annuloplasty using radiofrequency ablation to denervate the sinuvertebral nerve attached to the annulus under epidural anesthesia. Patient symptoms completely relieved at the postoperative period and continued upto recent follow up of 6 months. The classical presentation of the patient after herpes zoster infection as back pain with referred leg pain, disc degeneration on MRI, intraoperative evidence of chronic neuropathy and almost complete improvement in patient symptoms after radiofrequency ablation makes it a first reported case of sinuvertebral neuropathy following herpes zoster infection

Enhanced anti-cancer effect using MMP-responsive L-asparaginase fused with cell-penetrating 30Kc19 protein

As the acute lymphoblastic leukaemia (ALL) develops, expression of L-asparaginase (ASNase) protein is known to decrease. Therefore, deficiency of the ASNase protein would be regarded as one of the significant indications of the ALL. For the treatment of ALL, recombinant ASNase protein derived from bacterial origin is used which causes cytotoxicity by deprivation of Asn. However, short half-life of the protein is an obstacle for medical use. In order to overcome this limit, recombinant ASNase was fused to 30Kc19 with protein-stabilizing and cell-penetrating properties. As the 30Kc19 protein may induce steric hindrance, we further added a PLGLAG linker sequence (LK) between the ASNase and 30Kc19. The treatment of ASNase-LK-30Kc19 fusion protein demonstrated enhanced stability, cell-penetrating property, and anti-cancer activity. Intracellular delivery of both the non-cleaved and cleaved forms of the protein were observed, suggesting that ASNase acted both internally and externally, performing high anti-cancer activity by effective depletion of intracellular Asn. Additionally, ASNase-LK-30Kc19 showed high selectivity towards cancer cells. In terms of the dosage, releasable ASNase from ASNase-LK-30Kc19 reached the same half-maximal inhibitory concentration at a concentration five times lower than non-releasable ASNase-30Kc19. Altogether, the findings suggest that this fusion approach has potential applications in the treatment of ALL