We use diquark-antidiquark currents to investigate the masses and partial decay widths of the recently observed mesons D+sJ(2317), D*0(0)(2308) and X(3872), considered as four-quark states, in a QCD sum rule approach. In particular we investigate the coupling constant gDsJ DK. We found that the gDsJ DK obtained in this four-quark scenario is smaller than the coupling constant obtained when D+sJ(2317) is considered as a conventional cs state.

A buried Holocene marine bed was discovered upon drilling a water well in Algarrobo (33°22'S), located on the coast of central Chile. Radiocarbon dating of a wood fragment found within the deposit indicates an age of 6450 cal yr BP. The top of this bed, 0.25 m-thick, was reached at an elevation of 3.8 m above mean sea level. This bed contains abundant monospecific faunas of foraminifers (Ammonia tepida) and ostracodes (Cyprideis beaconensis), indicative of deposition in a very shallow, transitional marine environment. Palynologic analysis reveals a Chenopodiaceae-dominated (~70%) assemblage, indicating a relatively arid and warm climate

Una capa marina de edad holocena fue descubierta durante las faenas de excavación de un pozo en Algarrobo (33°22'S), situado en la zona costera de Chile central. Un fragmento de madera incorporado en este estrato dio una edad 14C de 6450 cal yr BP. El techo de esta capa, de 0,25 m de espesor, se sitúa a una altura de 3,8 m sobre el nivel medio del mar. Esta capa presenta una fauna abundante y monoespecífica de foraminíferos de la especie Ammonia tepida y de ostrácodos de la especie Cyprideis beaconensis, que son indicativos de un ambiente marino somero y transicional. El análisis palinológico indica la presencia de una asociación dominada por Chenopodiaceae (70%), indicativa de un clima relativamente árido y cálido

We calculate the masses of lambdab and lambdac in the framework of QCD sum rules including instanton contributions. We find that these contributions have the same size of the four quark condensate contribution and improve the Borel stability in both Dirac structures of the baryon correlation function.