Diffractive production of the charmed baryon Λ+c at the CERN ISR

In a sample of diffractive events of high multiplicity a sharp five standard deviation signal is observed at M = 2255 MeV/c² in the K^?pπ⁺ mass distribution and, although with less statistical strength, at the same mass in the Λ⁰π⁺π⁺π^? channel. These signals are identified as being due to the decay of the charmed baryon Λ⁺_c which is produced with a cross section times branching ratio σ_cB in the range 0.7?1.8 μb for the K^?π⁺p decay and 0.3?0.7 μb for the Λ^-π⁺π⁺ π^? system.     

Dichroisme circulaire d'olefines—V: Derives des acides pimariques

The Cotton effect of olefins in the pimaric acid series is discussed. The contribution of the vinyl group is important when it is near the endocyclic double bond and becomes negligible when the two double bonds are far apart.     

Migration reversible du methyle 19 en serie cholestane

Hydroxyketone $\text{4}$ is partially dehydrated and rearranged when heated at reflux temperature in DMF/BBr. Upon further heating, dienone $\text{5}$ suffered a reversible migration of the 19-methyl group C-5/C-10.     

Dielectric study of viscose rayon and viscose hydrocelluloses. I.

Both dielectric and x-ray results on viscose rayon and its hydrolysis residues show a rapid increase in the lateral order arrangement of the fiber chains in the earlier stages of hydrolysis. On the other hand, a divergence between the two measurements is found in the later stages of acid action. This is explained in terms of the role played by the fractions of molecular low dimensions which are in sensitive to x-ray diffraction but contribute to the polarizability of the dielectrics.     

A closed-form solution to a quadratic optimization problem in complex variables

A special quadratic optimization problem in complex variables is investigated for a closed-form solution. Two different approaches are used. The first is a direct approach which leads to a family of solutions defined in terms of arbitrary complex constants. The second is an indirect approach based on parametrizing the objective function. It leads to a specific solution, which is a member of the above family and which is shown to be bounded.     

Stimulated hyper-Raman emission from sodium vapour

The first observation of tunable stimulated hyper-Raman scattering is reported. A dye laser (ω_p) focussed into sodium vapour produced stimulated hyper-Raman emission (2ω_p?ω_3s-4p) at ～ 2.3 μm when 2ω_p was tuned near the 3s-4d two- photon resonance. Photon conversion efficiencies up to 2% were obtained. The hyper-Raman emission was tuned over a ～ 160 cm^?1 range, and could be observed with pump powers as low as ～ 2kW.     

Interaction between some metal tetrasulphonated phthalocyanines and apocytochrome-c

Artificial cytochromes-c have been prepared with zinc and vanadyl tetrasulphonated phthalocyanines in place of heme. Their structure and properties have been investigated by CD and difference spectroscopy, molecular weight determination and peptide fragments examination.     

Second-harmonic generation in a direct-bonded periodically poled LiNbO(3) buried waveguide

We report the fabrication of a 12-mum -thick periodically poled LiNbO(3) planar waveguide buried in LiTaO(3) by direct bonding of precision-polished surfaces. Frequency doubling of the 1064-nm output of a cw diode-pumped Nd:YAG laser was performed in a 5.5-mm-long device with a 6.50-mum -period grating at an elevated temperature of 174 degrees C. The resultant green second-harmonic output exhibited fundamental-spatial-mode characteristics at a 4.3%W(-1) conversion efficiency.     

Discovery of Chemicals to Either Clear or Indicate Amyloid Aggregates by Targeting Memory-Impairing Anti-Parallel Aβ Dimers

Amyloid-β (Aβ) oligomers are implicated in Alzheimer disease (AD). However, their unstable nature and heterogeneous state disrupts elucidation of their explicit role in AD progression, impeding the development of tools targeting soluble Aβ oligomers. Herein parallel and anti-parallel variants of Aβ(1–40) dimers were designed and synthesized, and their pathogenic properties in AD models characterized. Anti-parallel dimers induced cognitive impairments with increased amyloidogenesis and cytotoxicity, and this dimer was then used in a screening platform. Through screening, two FDA-approved drugs, Oxytetracycline and Sunitinib, were identified to dissociate Aβ oligomers and plaques to monomers in 5XFAD transgenic mice. In addition, fluorescent Astrophloxine was shown to detect aggregated Aβ in brain tissue and cerebrospinal fluid samples of AD mice. This screening platform provides a stable and homogeneous environment for observing Aβ interactions with dimer-specific molecules.