12 research outputs found
Ultralow Percolation Threshold in Aerogel and Cryogel Templated Composites
We
demonstrate a novel concept for preparing percolating composites
with ultralow filler content by utilizing nanofiller-loaded aerogel
and cryogels as a conductive template. This concept is investigated
for several porous systems, including resorcinol-formaldehyde (RF),
silica, and polyacrylamide (PAM) gels, and both graphene and carbon
nanotubes are utilized as nanofiller. In each case, a stable, aqueous
nanofiller dispersion is mixed with a sol–gel precursor and
polymerized to form a hydrogel, which can then be converted to an
aerogel by critical point drying or cryogel by freeze-drying. Epoxy
resin is infused into the pores of the gels by capillary action without
disrupting the monolithic structure. We show that conductive graphene/epoxy
composites are formed with a very low graphene loading; a percolation
threshold as low as 0.012 vol % is obtained for graphene-RF cryogel/epoxy
composite. This is the lowest reported threshold of any graphene-based
nanocomposites. Similar values are achieved in other aerogel and nanofiller
systems, which demonstrates the versatility of this method
Do neonates, infants and young children need a higher dose of enoxaparin in the cardiac intensive care unit?
Topical GZ21T Inhibits the Growth of Actinic Keratoses in a UVB-Induced Model of Skin Carcinogenesis
Actinic keratoses (AKs) are premalignant intraepidermal neoplasms that occur as a result of cumulative sun damage. AKs commonly relapse, and up to 16% undergo malignant transformation into cutaneous squamous cell carcinoma. There is a need for novel therapies that reduce the quantity and surface area of AKs as well as prevent malignant transformation to cutaneous squamous cell carcinomas. We recently showed that GZ17-6.02, an anticancer agent composed of curcumin, haramine, and isovanillin, inhibited the growth of H297.T cells. This study evaluated the efficacy of a topical formulation of GZ17-6.02, known as GZ21T, in a murine model of AK generated by exposing SKH1 mice to UVR. Treatment of mice with topical GZ21T inhibited the growth of AKs by decreasing both lesion count (P = 0.012) and surface area occupied by tumor (P = 0.002). GZ21T also suppressed the progression of AKs to cutaneous squamous cell carcinoma by decreasing the count (P = 0.047) and surface area (P = 0.049) of lesions more likely to represent cutaneous squamous cell carcinoma. RNA sequencing and proteomic analyses revealed that GZ21T suppressed several pathways, including MAPK (P = 0.025), phosphoinositide 3-kinase–protein kinase B (P = 0.04), HIF-1α (P = 0.016), Wnt (P = 0.025), insulin (P = 0.018), and ERBB (P = 0.016) signaling. GZ21T also upregulated the autophagy-promoting protein AMPK while suppressing proteins such as PD-L1, glutaminase, pAkt1 S473, and eEF2K
Preliminary screening of Houttuynia cordata for biological potential and chemical components using TLC and GC–MS analysis
Liquidity from Two Lending Facilities
During financial crises, the lender of last resort (LOLR) uses lending facilities to inject critical funding into the banking sector. The facilities need to be designed in such a way that banks are not reluctant to seek assistance due to stigma and that banks with liquidity concerns are attracted rather than those prone to risk-taking and moral hazard incentives. We use an unexpected disclosure that introduced stigma at one of two similar LOLRs during the Great Depression to evaluate whether banks used LOLR assistance to improve their liquidity needs using a novel trivariate model with recursive endogeneity. We find evidence that banks that approached the facility with stigma were less liquid and reduced their position of safe assets in comparison with banks that approached the facility with no stigma. Thus, stigma forced the pool of LOLR borrowers to separate into different groups of banks that ex-post revealed their liquidity preferences. This finding sheds light on why and when banks approach their LOLR.</jats:p