Spin dynamics and four-photon mixing in InSb

The spin flip Raman interaction can be used to excite coherent spin precession in semiconductors. Resonant, four-photon mixing is shown to be equivalent to Raman scattering from this coherent state. Studies of the four-photon intensity give information concerning spin dynamics (T₁ and T₂) in n-InSb.     

Über das Spektrum von Verbandshomomorphismen inC(X)

Ohne Zusammenfassung     

Self-centering combined aperture- and scatter-slit for powder diffractometry with constant effective specimen area

Summary A self-centering moving slit is described, which is used in the forward region to keep the effective specimen area constant. Construction and adjustment are simple. Stray radiation is entirely suppressed with appropriate sample holders.     

Differential proteome analysis of colon carcinoma cell line SW480 after reconstitution of the tumour suppressor Smad4

The tumour suppressor gene Smad4 is frequently inactivated in gastrointestinal carcinomas. Smad4 plays a pivotal role in transducing signals of the transforming growth factor-β (TGF-β) superfamily of proteins. Inactivation of Smad4 seems to occur late during tumour progression when tumours acquire invasive and metastatic properties. Identification of proteins directly or indirectly regulated by Smad4 would, therefore, ease the future design of new diagnostic and therapeutic strategies for gastrointestinal carcinoma. We have used human colon carcinoma cell line SW480 stably transfected with Smad4 as an in-vitro model system to identify Smad4-regulated proteins by applying two-dimensional gel electrophoresis (2DE) then MALDI-PMF/PFF-MS. We identified a total of 47 protein species with a Smad4-dependent expression. From the functions of the candidate proteins we obtained new insights into Smad4’s participation in processes, for example apoptosis, differentiation, and proliferation.     

C−C Bond Formation of Benzyl Alcohols and Alkynes Using a Catalytic Amount of KOtBu: Unusual Regioselectivity through a Radical Mechanism

We report a C?C bond‐forming reaction between benzyl alcohols and alkynes in the presence of a catalytic amount of KO^tBu to form α‐alkylated ketones in which the C=O group is located on the side derived from the alcohol. The reaction proceeds under thermal conditions (125 °C) and produces no waste, making the reaction highly atom efficient, environmentally benign, and sustainable. Based on our mechanistic investigations, we propose that the reaction proceeds through radical pathways.