The Tibetan Plateau, between the Kunlun Shan and the Himalayas, consists of terranes accreted successively to Eurasia. The northernmost, the Songban Ganzi Terrane, was accreted to the Kunlun (Tarim-North China Terrane) along the Kunlun-Qinling Suture during the late Permian. The Qiangtang Terrane accreted to the Songban-Ganzi along the Jinsha Suture during the late Triassic or earliest Jurassic, the Lhasa Terrane to the Qiangtang along the Banggong Suture during the late Jurassic and, finally, Peninsular India to the Lhasa Terrane along the Zangbo Suture during the Middle Eocene. The Kunlun Shan, Qiangtang and Lhasa Terranes are all underlain by Precambrian continental crust at least a billion years old. The Qiangtang and Lhasa Terranes came from Gondwanaland. Substantial southward ophiolite obduction occurred across the Lhasa Terrane from the Banggong Suture in the late Jurassic and from the Zangbo Suture in the latest Cretaceous-earliest Palaeocene. Palaeomagnetic data suggest successive wide Palaeotethyan oceans during the late Palaeozoic and early Mesozoic and a Neotethys which was at least 6000 km wide during the mid-Cretaceous. Thickening of the Tibetan crust to almost double the normal thickness occurred by northward-migrating north-south shortening and vertical stretching during the mid-Eocene to earliest Miocene indentation of Asia by India; Neogene strata are almost flat-lying and rest unconformably upon Palaeogene or older strata. Since the early Miocene, the northward motion of India has been accommodated principally by north south shortening both north and south of Tibet. From early Pliocene to the Present, the Tibetan Plateau has risen by about two kilometres and has suffered east-west extension. Little, if any, of the India Eurasia convergence has been accommodated by eastward lateral extrusion.

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Essential oils extracted from aromatic plants exhibit important biological activities and have become increasingly important for the development of aromatherapy for complementary and alternative medicine. The essential oil extracted from Cinnamomum cassia Presl (CC-EO) has various functional properties; however, little information is available regarding its anti-tyrosinase and anti-melanogenic activities. In this study, 16 compounds in the CC-EO have been identified; the major components of this oil are cis-2-methoxycinnamic acid (43.06%) and cinnamaldehyde (42.37%). CC-EO and cinnamaldehyde exhibited anti-tyrosinase activities; however, cis-2-methoxycinnamic acid did not demonstrate tyrosinase inhibitory activity. In murine B16 melanoma cells stimulated with α-melanocyte-stimulating hormone (α-MSH), CC-EO and cinnamaldehyde not only reduced the melanin content and tyrosinase activity of the cells but also down-regulated tyrosinase expression without exhibiting cytotoxicity. Moreover, CC-EO and cinnamaldehyde decreased thiobarbituric acid-reactive substance (TBARS) levels and restored glutathione (GSH) and catalase activity in the α-MSH-stimulated B16 cells. These results demonstrate that CC-EO and its major component, cinnamaldehyde, possess potent anti-tyrosinase and anti-melanogenic activities that are coupled with antioxidant properties. Therefore, CC-EO may be a good source of skin-whitening agents and may have potential as an antioxidant in the future development of complementary and alternative medicine-based aromatherapy.

The 1:500,000 coloured geological map of the traverse route combines observations from the Geotraverse, previous mapping, and interpretation of orbital images. The position of all localities visited by Geotraverse participants and basic geological data collected by them along the traverse route are shown on a set of maps originally drawn at 1:100,000 scale, reproduced on microfiche for this publication. More detailed mapping, beyond a single line of section, was achieved in five separate areas. The relationships between major rock units in these areas, and their significance, are outlined in this paper. Near Gyanco, (Lhasa Terrane) an ophiolite nappe, apparently connected with outcrops of ophiolites in the Banggong Suture about 100 km to the north, was under thrust by a discontinuous slice of Carboniferous—Permian clastic rocks and limestone, contrary to a previous report of the opposite sequence. At Amdo, a compressional left-lateral strike-slip fault zone has modified relationships along the Banggong Suture. Near Wuli, (northern Qiangtang Terrane) limited truncation of Triassic strata at the angular unconformity below Eocene redbeds demonstrates that most of the folding here is of Tertiary age. The map of the nearby Erdaogou region displays strong fold and thrust-shortening of the Eocene redbeds, evidence of significant crustal shortening after the India- Asia collision began. In the Xidatan-Kunlun Pass area, blocks of contrasting Permo—Triassic rocks are separated by east-trending faults. Some of these faults are ductile and of late Triassic — early Jurassic age, others are brittle and part of the Neogene—Quaternary Kunlun leftlateral strike-slip fault system. Some more significant remaining problems that geological mapping might help to solve are discussed briefly, including evidence for a possible additional ophiolitic suture within the Qiangtang Terrane.

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uptured sinus of Valsalva aneurysms (RSVA) are rare and usually occurs in adolescence to early adulthood. 1 They are most commonly congenital in origin and caused by a weakness of the wall of the sinus Valsalva above the aortic valve annulus and leads to progressive dilatation, eventually rupturing into one of the 4 chambers of the heart or the mediastinum. 2 The aneurysm most commonly arises from the right coronary sinus (RCS) of Valsalva and most frequently ruptures into the right ventricle with a wind-sock like structure projecting from the sinus into which it ruptures. Surgical repair is the traditional treatment for RSVA. 3 With the advent of the transcatheter technique, transcatheter closure of the RSVA could be an alternative treatment. We report the results of transcatheter treatment of RSVA in 4 patients. with sudden-onset exertional dyspnea and palpitation. Bounding pulses and a continuous murmur could be detected in all patients. The diagnosis of RSVA is based on transthoracic 2-dimensional (D) echocardiography with color Doppler and angiography. Two patients had a cardiac chamber dilatation. All 4 patients underwent attempted transcatheter closure of the RSVA after obtaining consent from the patient or parents. Methods ProceduresUnder local anesthesia, the femoral vein and artery were cannulated with a sheath. Heparin (50 units/kg) was administered before the procedure and one dose of cephradine arginine was given. Hemodynamic studies and angiography were performed in all patients to calculate the pulmonaryto-systemic ratio (Qp:Qs) and to delineate the morphology of RSVA and the opening site (Fig 1). After general anesthesia, transesophageal echocardiography (TEE) was performed to monitor the procedure. The maximal diameter of the aortic opening of the RSVA was measured on multiplane TEE images. The distance between the aortic opening site of the RSVA and the right or left coronary ostium was also measured on TEE images. A 5 or 6Fr right Judkin catheter was advanced from the right femoral artery to the ostium of the RSVA. A 0.014 coronary extra-support guidewire (Boston Scientific, SCIMED, Natick, MA, USA) with a soft and floppy end was advanced through the catheter into the right atrium or the main pulmonary artery. A 10-mm Goose Neck Snare (Microvena, White Bear Lake, MN, USA) was advanced through the right femoral venous sheath, snared the coronary guidewire in the right atrium or the main pulmonary artery, and exteriorized the coronary wire through the right femoral vein. An arteriovenous rail