1,921 research outputs found
Hybrid gold single crystals incorporating amino acids
Composite hybrid gold crystals are of profound interest in various research
areas ranging from materials science to biology. Their importance is due to
their unique properties and potential implementation, for example in sensing or
in bio-nanomedicine. Here we report on the formation of hybrid organic-metal
composites via the incorporation of selected amino acids histidine, aspartic
acid, serine, glutamine, alanine, cysteine, and selenocystine into the crystal
lattice of single crystals of gold. We used electron microscopy, chemical
analysis and high-resolution synchrotron powder X ray diffraction to examine
these composites. Crystal shape, as well as atomic concentrations of occluded
amino acids and their impact on the crystal structure of gold, were determined.
Concentration of the incorporated amino acid was highest for cysteine, followed
by serine and aspartic acid. Our results indicate that the incorporation
process probably occurs through a complex interaction of their individual
functional groups with gold atoms. Although various organic gold composites
have been prepared, to the best of our knowledge this is the first reported
finding of incorporation of organic molecules within the gold lattice. We
present a versatile strategy for fabricating crystalline nanohybrid composite
gold crystals of potential importance for a wide range of applications
Reconsideration of Forced Arbitration in Data Privacy Legislation
Pre-dispute arbitration principles were established in 1925 by Congress through the Federal Arbitration Act (FAA) and were meant to “create an efficient way for businesses with comparable bargaining power to negotiate and agree upon an alternative means of conflict resolution.” However, the driving legal maxims behind the FAA failed to address cases with a large power imbalance between the parties. Arbitration in such cases usually see a company “likely be[ing] represented in arbitration by lawyers who are well-versed in the process and the issue involved, while the wronged customer must find an attorney willing to represent them for what is likely a meager award, if any.” The benefits of forced arbitration led to corporations adopting the practice on a massive scale to the extent where the advocacy group Public Citizen put forth a statement that “[f]orced arbitration has crept into virtually every sector of Americans’ lives.”
This post was originally published on the Cardozo Journal of Conflict Resolution website on October 10, 2022. The original post can be accessed via the Archived Link button above
Does PPP hold for Big Mac price or consumer price index? Evidence from panel cointegration
This paper examines the validity of purchasing power parity (PPP) using CPI and Big Mac prices. The benchmark model, i.e., the OLS method, which does not take nonstationarity into account, rejects the hypothesis of PPP regardless of prices used. We next use the panel cointegration method to consider the nonstationary nature of variables. Estimated results for CPI are mixed. The PPP is rejected when the nominal exchange rate is employed as the dependent variable but is not rejected when the price ratio is used as the dependent variable. By contrast, the PPP is overwhelmingly not rejected when the Big Mac price is used. Last, we remove the production bias and re-examine the same issue by using panel cointegration. The PPP is again decisively rejected when CPI price is used but not for Big Mac price. Accordingly, Big Mac price is more supportive to the validity of PPP than CPI price.Big Mac
Enhancement of osteoblastogenesis and suppression of osteoclastogenesis by inhibition of de-phosphorylation of eukaryotic translation initiation factor 2 alpha
The phosphorylation of eukaryotic translation initiation factor 2 alpha (eIF2α) is activated in response to various stresses such as viral infection, nutrient deprivation, and stress to the endoplasmic reticulum. Severe stress to the endoplasmic reticulum, for instance, induces an apoptotic pathway, while mild stress, on the contrary, leads to a pro-survival pathway. Little has been known about the elaborate role of eIF2α phosphorylation in the development of bone-forming osteoblasts and bone-resorbing osteoclasts. Using salubrinal and guanabenz as inhibitors of the de-phosphorylation of eIF2α, we have recently reported that the phosphorylation of eIF2α significantly alters fates of both osteoblasts and osteoclasts. Based on our recent findings, we review in this research highlight the potential mechanisms of the enhancement of osteoblastogenesis and the suppression of osteoclastogenesis through the elevated level of phosphorylated eIF2α
Recommended from our members
The variation in transparency of amniotic membrane used in ocular surface regeneration
Background/aims: Scant consideration has been given
to the variation in structure of the human amniotic
membrane (AM) at source or to the significance such
differences might have on its clinical transparency.
Therefore, we applied our experience of quantifying
corneal transparency to AM.
Methods: Following elective caesarean, AM from areas
of the fetal sac distal and proximal (ie, adjacent) to the
placenta was compared with freeze-dried AM. The
transmission of light through the AM samples was
quantified spectrophotometrically; also, tissue thickness
was measured by light microscopy and refractive index by
refractometry.
Results: Freeze-dried and freeze-thawed AM samples
distal and proximal to the placenta differed significantly in
thickness, percentage transmission of visible light and
refractive index. The thinnest tissue (freeze-dried AM) had
the highest transmission spectra. The thickest tissue
(freeze-thawed AM proximal to the placenta) had the
highest refractive index. Using the direct summation of
fields method to predict transparency from an equivalent
thickness of corneal tissue, AM was found to be up to
85% as transparent as human cornea.
Conclusion: When preparing AM for ocular surface
reconstruction within the visual field, consideration should
be given to its original location from within the fetal sac
and its method of preservation, as either can influence
corneal transparency
An Earth Orbiting Satellite Service and Repair Facility
A conceptual design was produced for the Geosynchronous Satellite Servicing Platform (GSSP), an orbital facility capable of repairing and servicing satellites in geosynchronous orbit. The GSSP is a man-tended platform, which consists of a habitation module, operations module, service bay and truss assembly. This design review includes an analysis of life support systems, thermal and power requirements, robotic and automated systems, control methods and navigation, and communications systems. The GSSP will utilize existing technology available at the time of construction, focusing mainly on modifying and integrating existing systems. The entire facility, along with two satellite retrieval vehicles (SRV), will be placed in geosynchronous orbit by the Advanced Launch System. The SRV will be used to ferry satellites to and from the GSSP. Technicians will be transferred from Earth to the GSSP and back in an Apollo-derived Crew Transfer Capsule (CTC). These missions will use advanced telerobotic equipment to inspect and service satellites. Four of these missions are tentatively scheduled per year. At this rate, the GSSP will service over 650 satelites during the projected 25 year lifespan
- …