Anglicismos y vida docente

Pertenece a la sección diaria del CVC (Centro Virtual Cervantes).Una de las vías de entrada de anglicismos en nuestra lengua es el mundo universitario y escolar.Peer reviewe

4-(4-Chloro­phen­yl)-1-(2-hydr­oxy-2,2-di­phenyl­acet­yl)thio­semicarbazide

The asymmetric unit of the title compound, C21H18ClN3O2S, contains two mol­ecules in which the bond lengths and angles are almost identical. Intra­molecular N—H⋯S hydrogen bonds result in the formation of two five-membered rings. In the crystal structure, inter­molecular N—H⋯O hydrogen bonds link the mol­ecules into centrosymmetric dimers; these dimers are linked via inter­molecular O—H⋯S hydrogen bonds, leading to infinite corrugated layers parallel to the bc plane through R 2 2(16) ring motifs

Disturbed Clockwork Resetting in Sharp-1 and Sharp-2 Single and Double Mutant Mice

BACKGROUND: The circadian system provides the basis to anticipate and cope with daily recurrent challenges to maintain the organisms' homeostasis. De-synchronization of circadian feedback oscillators in humans causes 'jet lag', likely contributes to sleep-, psychiatric-, metabolic disorders and even cancer. However, the molecular mechanisms leading to the disintegration of tissue-specific clocks are complex and not well understood. METHODOLOGY/PRINCIPAL FINDINGS: Based on their circadian expression and cell culture experiments, the basic Helix-Loop-Helix (bHLH) transcription factors SHARP-1(Dec2) and SHARP-2(Stra13/Dec1) were proposed as novel negative regulators of the molecular clock. To address their function in vivo, we generated Sharp-1 and Sharp-2 single and double mutant mice. Our experiments reveal critical roles for both factors in regulating period length, tissue-specific control of clock gene expression and entrainment to external cues. Light-pulse experiments and rapid delays of the light-dark cycle (experimental jet lag) unravel complementary functions for SHARP-1 and SHARP-2 in controlling activity phase resetting kinetics. Moreover, we show that SHARP-1 and 2 can serve dual functions as repressors and co-activators of mammalian clock gene expression in a context-specific manner. This correlates with increased amplitudes of Per2 expression in the cortex and liver and a decrease in the suprachiasmatic nucleus (SCN) of double mutant mice. CONCLUSIONS/SIGNIFICANCE: The existence of separate mechanisms regulating phase of entrainment, rhythm amplitude and period length has been postulated before. The differential effects of Sharp-deficiency on rhythmicity and behavioral re-entrainment, coupled to tissue-dependent regulatory functions, provide a new mechanistic basis to further understand the complex process of clock synchronizations

Phosphine-Stabilized Pnictinidenes

The reaction of the intramolecular germylene‐phosphine Lewis pair (o‐PPh(2))C(6)H(4)GeAr* (1) with Group 15 element trichlorides ECl(3) (E=P, As, Sb) was investigated. After oxidative addition, the resulting compounds (o‐PPh(2))C(6)H(4)(Ar*)Ge(Cl)ECl(2) (2: E=P, 3: E=As, 4: E=Sb) were reduced by using sodium metal or LiHBEt(3). The molecular structures of the phosphine‐stabilized phosphinidene (o‐PPh(2))C(6)H(4)(Ar*)Ge(Cl)P (5), arsinidene (o‐PPh(2))C(6)H(4)(Ar*)Ge(Cl)As (6) and stibinidene (o‐PPh(2))C(6)H(4)(Ar*)Ge(Cl)Sb (7) are presented; they feature a two‐coordinate low‐valent Group 15 element. After chloride abstraction, a cyclic germaphosphene [(o‐PPh(2))C(6)H(4)(Ar*)GeP] [B(C(6)H(3)(CF(3))(2))(4)] (8) was isolated. The (31)P NMR data of the germaphosphene were compared with literature examples and analyzed by quantum chemical calculations. The phosphinidene was treated with [iBu(2)AlH](2), and the product of an Al−H addition to the low‐valent phosphorus atom (o‐PPh(2))C(6)H(4)(Ar*)Ge(H)P(H)Al(C(4)H(9))(2) (9) was characterized