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In 1991-1995 by using the Rieckmann in vitro micro-method, susceptibilities of Plasmodium falciparum to eight antimalarials in the China-Lao PDR and China-Myanmar border areas were tested. The resistant rates of P. falciparum to chloroquinine were 95.0%-100%; IC50 114-240nmol/l. P. falciparum resistant rates to amodiaquine resistance accounted for 83.5%-100%, IC50 52-72nmol/l. All cases were sensitive to quinine, IC50 470-608nmol/l. P. falciparum isolates from the Lao PDR frontier were highly sensitive to artesunate, dihydroartemisinin, and arteether. Resistant rates from other areas were 0-11%. P. falciparum from China-Myanmar and Lao PDR border areas were also sensitive to mefloquine, IC50 68-88nmol/l. A longitudinal survey of the sensitivity of P. falciparum in vivo on the China-Lao PDR border showed that the average defervescent time of falciparum malaria was treated by pyronaridine increased from 32.7 +/- 16.0 hours during 1984-85 to 56.2 +/- 27.4 hours in 1995; the recrudescence rate rose up from 15.2% to 37.5%. The results monitored in vitro showed that all cases assessed in 1988 for response to pyronaridine were sensitive, but 36.4% of cases had emerging resistance, IC50 increased from 13nmol/l to 40 nmol/l. The above results suggested that P. falciparum in these areas has expressed resistance to chloroquine and amodiaquine. However, the parasites are still sensitive to artemisinin, pyronaridine, mefloquine, quinine, but with a declining sensitivities.

Relativistic configuration interaction calculations of five ω–ω states [3/2, 1/2, 1/2(II), 3/2(II), 5/2] of TeH are carried out. Comparison calculations of the 2Π and 4Π λ–s states are also carried out with the objective of understanding the effect of spin–orbit interaction on the electronic states of TeH. These calculations enable assignment of some of the experimentally observed spectra. The 1/2(II), 3/2(II), and 5/2 states exhibit interesting avoided crossings.

Complete active space MCSCF (CASSCF) followed by multireference singles and doubles configuration interaction (MRSDCI) calculations are carried out on 13 electronic states of PdH2 and 9 electronic states of PdH+ . The bending potential energy surfaces of 1A1 and 3A1 electronic states were obtained. The 1A1 surface contains two bent minima (θe =30° and θe =62°) and a higher linear minimum separated by a saddle point. The 3A1 surface is relatively flat in the region of the saddle point. The Pd(1S0 ) atom forms a weak complex with H2 but inserts spontaneously into H2 while the Pd(3D3 ) atom has to surmount a large barrier for insertion into H2. The spin–orbit effects for the electronic states of PdH2 are estimated through relativistic configuration interaction calculations of PdH+ whose d Mulliken population is close to that of the d population of PdH2. The ground state of PdH2 is found to be a weakly bound bent 1A1 state with θe =30° and re (Pd–H)=1.67 A. The electronic state and potential energy surfaces o...

Complete active space MCSCF (CASSCF) and second‐order configuration interaction (SOCI) calculations of low‐lying electronic states [2B2,2A1] of Au3 as well as the 1Σ+g state of Au2 are carried out. The bending potential energy surfaces of 2A1 and 2B2 states are also presented. A barrier is found in the potential energy surface of the 2A1 state in moving from the linear to bent structure. Two nearly‐degenerate structures are found for the ground state. The 2Σ+u state arising from the linear structure with an Au–Au bond length of 2.66 A is only 3.2 kcal/mol below the 2A1 bent state. The equilibrium geometry of the 2A1 state is an isosceles triangle with an apex angle of 54°. The Au3 cluster is found to be more stable than the gold dimer. The effect of d correlation is studied on Au2 by carrying out MRSDCI (multireference singles and doubles CI) calculations on the 1Σ+g state of Au2 which include excitations from the d orbitals.