A preliminary study on the climatic change of the hengduan mountains area since 1600 A.D.

1988 ◽  
Vol 5 (4) ◽  
pp. 437-443 ◽  
Author(s):  
Wu Xiangding ◽  
Lin Zhenyao ◽  
Sun Li
Keyword(s):  
Climatic Change ◽  
Hengduan Mountains ◽  
Preliminary Study

scholarly journals Pollen-based reconstruction of vegetational and climatic change over the past ~30 ka at Shudu Lake in the Hengduan Mountains of Yunnan, southwestern China

PLoS ONE ◽  
2017 ◽  
Vol 12 (2) ◽  
pp. e0171967 ◽  
Author(s):  
Yi-Feng Yao ◽  
Xiao-Yan Song ◽  
Alexandra H. Wortley ◽  
Yu-Fei Wang ◽  
Stephen Blackmore ◽  
...  
Keyword(s):  
Climatic Change ◽  
Southwestern China ◽  
Hengduan Mountains ◽  
The Past

scholarly journals A 22 570-year record of vegetational and climatic change from Wenhai Lake in the Hengduan Mountains biodiversity hotspot, Yunnan, Southwest China

2015 ◽  
Vol 12 (5) ◽  
pp. 1525-1535 ◽  
Author(s):  
Y. F. Yao ◽  
X. Y. Song ◽  
A. H. Wortley ◽  
S. Blackmore ◽  
C. S. Li
Keyword(s):  
Climatic Change ◽  
Southwest China ◽  
Human Impacts ◽  
Early Stage ◽  
Biodiversity Hotspot ◽  
Pollen Record ◽  
Hengduan Mountains ◽  
The Core ◽  
Broad Leaved Forest ◽  
Leaved Forest

Abstract. The Hengduan Mountains, with their strong altitudinal vegetation zonation, form a biodiversity hotspot which offers the potential for comparison between sites in order to understand how this zonation arose and how it has responded to climate change and human impacts through time. This paper presents a 22 570-year pollen record of vegetational and climatic change based on a core 320 cm in depth collected from Wenhai Lake on Jade Dragon Snow Mountain, one of the highest peaks in the Hengduan Mountains region of Yunnan, Southwest China. From 22 570 to 21 140 cal yr BP, the vegetation was dominated by broad-leaved forest (comprising mainly Quercus, Betula and Castanopsis), accompanied by needle-leaved forest (mainly Pinus and Abies), indicating a rather cold and dry climate relative to the present followed by cold and wet conditions. In the period between 21 140 and 19 350 cal yr BP, the vegetation was still dominated by broad-leaved forest and needle-leaved forest as before but with a notable increase in Betula pollen and a sharp decrease in Quercus pollen, implying a relatively cold and dry climate with several fluctuations in humidity. The period 19 350 to 17 930 cal yr BP was a transition stage from broad-leaved forest to needle-leaved forest, with a dramatic decrease in Quercus pollen and a maximum reading for Abies pollen, reflecting the coldest and driest climate since 22 570 cal yr BP. The expansion in needle-leaved forest dominated by Pinus and Abies (22 570–17 930 cal yr BP) along with an increase of Betula might correspond to the Last Glacial Maximum (LGM; the start of the LGM perhaps occurred prior to the basal age of the core). Between 17 930 and 9250 cal yr BP, needle-leaved forest declined and broad-leaved forest began to increase at first, suggesting increases in temperature and humidity, while towards the end of the period, needle-leaved forest expanded and broad-leaved forest shrank, indicating a colder and drier climate, possibly corresponding to the Younger Dryas. From 9250 cal yr BP to the present, the vegetation has been dominated by needle-leaved forest (comprising mainly Pinus, Abies and Tsuga), interspersed with broad-leaved Quercus and Betula, reflecting a significant decline in humidity from the early to late Holocene. During this period, human activity likely increased in this region, with impacts on the vegetation such as a distinct decrease in Pinus and Quercus pollen and an increase in Polygonaceae pollen in the upper 30 cm of the core. The marked decline in Quercus pollen compared with the early stage of this period, in particular, in the Wenhai core can be correlated with that observed in the Haligu core (situated about 2 km away) between 2400 cal yr BP and the present.

scholarly journals A 22 570 yr record of vegetational and climatic change from Wenhai Lake in the Hengduan Mountains biodiversity hotspot, Yunnan, Southwest China

2014 ◽  
Vol 11 (9) ◽  
pp. 13433-13453 ◽  
Author(s):  
Y. F. Yao ◽  
X. Y. Song ◽  
A. H. Wortley ◽  
S. Blackmore ◽  
C. S. Li
Keyword(s):  
Climatic Change ◽  
Southwest China ◽  
Human Impacts ◽  
Climatic Conditions ◽  
Biodiversity Hotspot ◽  
Pollen Record ◽  
Hengduan Mountains ◽  
Humid Climate ◽  
Broad Leaved Forest ◽  
Leaved Forest

Abstract. The Hengduan Mountains, with their strong altitudinal vegetation zonation, form a biodiversity hotspot which offers the potential for comparison between sites in order to understand how this zonation arose and how it has responded to climate change and human impacts through time. This paper is one of the studies covering a range of altitudes within this hotspot, and presents a 22 570 yr pollen record of vegetational and climatic change based on a core 320 cm in depth collected from Wenhai Lake on the Jade Dragon Snow Mountain, one of the highest peaks in the Hengduan Mountains region of Yunnan, Southwest China. From 22 570 to 21 140 cal. yr BP, the vegetation was dominated by broad-leaved forest (comprising mainly Quercus, Betula and Castanopsis), accompanied by coniferous Pinus and Abies and the drought-tolerant herb Artemisia, indicating a cool and dry climate. In the period between 21 140 and 19 350 cal. yr BP, the vegetation was still dominated by broad-leaved forest but with a notable increase in pollen of aquatic plants, implying a relatively warm and moderately humid climate. The period 19 350 to 17 930 cal. yr BP was a transition stage from broad-leaved forest to needle-leaved forest, reflecting a warm-humid climate at the beginning and a cold-dry one at the end. Between 17 930 and 9250 cal. yr BP, needle-leaved forest and broad-leaved forest alternated in dominance in the early stages, with the former taking the predominant position by the end of the period, suggesting a climate fluctuating between warm-humid and cold-dry. From 9250 cal. yr BP to present, the vegetation has been dominated by needle-leaved forest (comprising mainly Pinus and Abies), coupled with broad-leaved forest (mainly Quercus and Betula), reflecting a transition in climatic conditions from warm-humid to cold-humid. During this period, human activity increased in this region, with impacts on the vegetation which may be evidenced by the distinct decrease in Pinus and Quercus pollen and an increase in Polygonaceae pollen in the upper 30 cm of the core. The marked decline in Quercus pollen, in particular, in the Wenhai core can be correlated with that observed in the Haligu core (situated about 2 km away) between 2400 cal. yr BP and the present.

The Ultrastructure of Metastatic Human Mammary Carcinoma After Prolonged Estrogen Therapy

1967 ◽  
Vol 25 ◽  
pp. 180-181
Author(s):  
John H.L. Watson ◽  
John L. Swedo ◽  
R.W. Talley
Keyword(s):  
Mammary Carcinoma ◽  
Osmium Tetroxide ◽  
Estrogen Therapy ◽  
Ultrastructural Level ◽  
Uranyl Acetate ◽  
Human Mammary Carcinoma ◽  
Surgical Biopsy ◽  
Lead Hydroxide ◽  
Preliminary Study ◽  
Hormonal Therapies

A preliminary study of human mammary carcinoma on the ultrastructural level is reported for a metastatic, subcutaneous nodule, obtained as a surgical biopsy. The patient's tumor had responded favorably to a series of hormonal therapies, including androgens, estrogens, progestins, and corticoids for recurring nodules over eight years. The pertinent nodule was removed from the region of the gluteal maximus, two weeks following stilbestrol therapy. It was about 1.5 cms in diameter, and was located within the dermis. Pieces from it were fixed immediately in cold fixatives: phosphate buffered osmium tetroxide, glutaraldehyde, and paraformaldehyde. Embedment in each case was in Vestopal W. Contrasting was done with combinations of uranyl acetate and lead hydroxide.

Fine structure of early degenerating myofibers in the tibialis anterior of young ‘MDX’ mouse

1988 ◽  
Vol 46 ◽  
pp. 322-323
Author(s):  
H.D. Geissinger ◽  
C.K. McDonald-Taylor
Keyword(s):  
Fine Structure ◽  
Muscle Regeneration ◽  
Tibialis Anterior ◽  
Genetic Defect ◽  
Mdx Mouse ◽  
Mdx Mice ◽  
Histopathological Changes ◽  
Electron Microscopic ◽  
Dystrophic Mouse ◽  
Preliminary Study

A new strain of mice, which had arisen by mutation from a dystrophic mouse colony was designated ‘mdx’, because the genetic defect, which manifests itself in brief periods of muscle destruction followed by episodes of muscle regeneration appears to be X-linked. Further studies of histopathological changes in muscle from ‘mdx’ mice at the light microscopic or electron microscopic levels have been published, but only one preliminary study has been on the tibialis anterior (TA) of ‘mdx’ mice less than four weeks old. Lesions in the ‘mdx’ mice vary between different muscles, and centronucleation of fibers in all muscles studied so far appears to be especially prominent in older mice. Lesions in young ‘mdx’ mice have not been studied extensively, and the results appear to be at variance with one another. The degenerative and regenerative aspects of the lesions in the TA of 23 to 26-day-old ‘mdx’ mice appear to vary quantitatively.

Ultrastructural observations of the aorta of calves implanted with a mechanical left ventricular assist device

1990 ◽  
Vol 48 (3) ◽  
pp. 834-835
Author(s):  
J P Cassella ◽  
V Salih ◽  
T R Graham
Keyword(s):  
Left Ventricular Assist Device ◽  
Ventricular Assist Device ◽  
Left Ventricular ◽  
Aortic Tissue ◽  
Assist Device ◽  
Ventricular Assist ◽  
Transmission Electron ◽  
Left Ventricular Assist ◽  
Preliminary Study

Left ventricular assist systems are being developed for eventual long term or permanent implantation as an alternative to heart transplantation in patients unsuitable for or denied the transplant option. Evaluation of the effects of these devices upon normal physiology is required. A preliminary study was conducted to evaluate the morphology of aortic tissue from calves implanted with a pneumatic Left Ventricular Assist device-LVAD. Two 3 month old heifer calves (calf 1 and calf 2) were electively explanted after 128 days and 47 days respectively. Descending thoracic aortic tissue from both animals was removed immediately post mortem and placed into karnovsky’s fixative. The tissue was subsequently processed for transmission electron microscopy (TEM). Some aortic tissue was fixed in neutral buffered formalin and processed for routine light microscopy.

A preliminary study on the potential of front face fluorescence spectroscopy for the discrimination of Moroccan virgin olive oils and the prediction of their quality

2021 ◽  
Author(s):  
Hicham Zaroual ◽  
El Mestafa El Hadrami ◽  
Romdhane Karoui
Keyword(s):  
Fluorescence Spectroscopy ◽  
Olive Oil ◽  
Virgin Olive Oil ◽  
Front Face ◽  
Virgin Olive Oils ◽  
Olive Oils ◽  
Preliminary Study

This study examines the feasibility of using front face fluorescence spectroscopy (FFFS) to authenticate 41 virgin olive oil (VOO) samples collected from 5 regions in Morocco during 2 consecutive crop seasons.

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