scholarly journals Tradeoff in the supply and demand for CO 2 dominates the divergence of net photosynthesis rates of functional plants in alpine ecosystems

2021 ◽  
Author(s):  
Hongyun Yao ◽  
Xiao-Yan Li ◽  
Cicheng Zhang ◽  
Pei Wang ◽  
Fangzhong Shi ◽  
...  
Keyword(s):  
Alpine Meadow ◽  
Supply And Demand ◽  
Net Photosynthesis ◽  
Photosynthetic Electron Transport ◽  
Dominant Factor ◽  
Regional Heterogeneity ◽  
Carboxylase Activity ◽  
Alpine Steppe ◽  
Large Increment ◽  
The Difference

As regional heterogeneity on the Qinghai Tibetan Plateau (QTP), the “greening rate” between alpine steppe in the west and alpine meadow ecosystems in the east is difference during the past several decades. To investigate the difference, the net photosynthetic rate (An) and the supply (mesophyll conductance ( g), stomatal conductance ( g)) and demand (the maximum rates of Rubisco carboxylase activity ( V) and photosynthetic electron transport ( J)) for CO of three plants functional types (PFTs) were measured. Other functional traits and influencing factors were compared among ecosystems along the altitudinal gradients of QTP. The An of the PFTs was simulated under potential future conditions. At high altitudes, grass was found to maintain a relatively stable An by decreasing V, J, and g, while slightly increasing g, compared with that at a low altitude. The An of sedge and shrubs increased with rising V, J and g and g values, resulting in a large increment in the An at low altitudes. Grass seemed to be less sensitive to the environment by reducing the supply of and holding onto CO , while sedge and shrub increased both. Grass and sedge should be divided into two PFTs rather than remaining as one based on their opposite physiological and morphological functions in response to climate change. The ecosystem at 3600 m was transitional. C was likely to be a more dominant factor than T in affecting the An of grass. The order of rising An in PFTs was shrub > sedge > grass and the An of alpine meadow was found to increase more under the two future climate scenarios.

scholarly journals Spatial and Temporal Differences in Alpine Meadow, Alpine Steppe and All Vegetation of the Qinghai-Tibetan Plateau and Their Responses to Climate Change

2021 ◽  
Vol 13 (4) ◽  
pp. 669
Author(s):  
Hanchen Duan ◽  
Xian Xue ◽  
Tao Wang ◽  
Wenping Kang ◽  
Jie Liao ◽  
...  
Keyword(s):  
Climate Change ◽  
Alpine Meadow ◽  
Global Climate ◽  
Growing Season ◽  
Tibet Plateau ◽  
Vegetation Types ◽  
Analysis Method ◽  
Alpine Steppe ◽  
Qinghai Tibet Plateau ◽  
Variation Trends

Alpine meadow and alpine steppe are the two most widely distributed nonzonal vegetation types in the Qinghai-Tibet Plateau. In the context of global climate change, the differences in spatial-temporal variation trends and their responses to climate change are discussed. It is of great significance to reveal the response of the Qinghai-Tibet Plateau to global climate change and the construction of ecological security barriers. This study takes alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau as the research objects. The normalized difference vegetation index (NDVI) data and meteorological data were used as the data sources between 2000 and 2018. By using the mean value method, threshold method, trend analysis method and correlation analysis method, the spatial and temporal variation trends in the alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau were compared and analyzed, and their differences in the responses to climate change were discussed. The results showed the following: (1) The growing season length of alpine meadow was 145~289 d, while that of alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau was 161~273 d, and their growing season lengths were significantly shorter than that of alpine meadow. (2) The annual variation trends of the growing season NDVI for the alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau increased obviously, but their fluctuation range and change rate were significantly different. (3) The overall vegetation improvement in the Qinghai-Tibet Plateau was primarily dominated by alpine steppe and alpine meadow, while the degradation was primarily dominated by alpine meadow. (4) The responses between the growing season NDVI and climatic factors in the alpine meadow, alpine steppe and the overall vegetation of the Qinghai-Tibet Plateau had great spatial heterogeneity in the Qinghai-Tibet Plateau. These findings provide evidence towards understanding the characteristics of the different vegetation types in the Qinghai-Tibet Plateau and their spatial differences in response to climate change.

scholarly journals Analisis Faktor Produksi Kalapa Sawit Rakyat Menurut Tipologi Lahan di Kabupaten Indragiri Hilir Provinsi Riau

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Heriyanto Heriyanto ◽  
Asrol Asrol ◽  
Detri Karya ◽  
Verry Yarda Ningsih
Keyword(s):  
Palm Oil ◽  
Oil Palm ◽  
Raw Materials ◽  
Least Square ◽  
Added Value ◽  
Dominant Factor ◽  
Factors Affecting ◽  
The Difference ◽  
Cultivation Techniques ◽  
Coastal Land

Heriyanto et al, 2018. Analysis of the Production Factors of the People's Palm Oil According to the Land Typology in Indragiri Hilir Regency, Riau Province. JLSO 7(1): Palm oil commodities are one of the plantation sub-sector commodities that increase the income of farmers and the community, provide processing industry raw materials that create added value. The land cultivated by independent oil palm farmers consists of land land, tidal peatlands, coastal peatlands and coastal land. The difference in typology of this land will contribute to different production. The research aimed to analyze the oil palm production and the dominant factor affecting oil palm production according to the typology of land in Indragiri Hilir Riau Province. The data were analyzed using descriptive statistics and built multiple regression models with the dummy variable method of Ordinary Least Square (OLS). The results of the study showed that the production of oil palm cultivation on land is the highest compared to the typology of tidal peatland, coastal peat and coastal land. The dominant factors affecting palm oil production in Indragiri Hilir Regency were the amount of fertilizer use, labor, age of plants, herbicides and dummy typology of land. In order to obtain optimal production, this study recommended doing oil palm farming in accordance with the correct cultivation techniques in accordance with the characteristics of land typology. Besides that the use of balanced fertilizer (elements of N, P, and K) in accordance with the recommended needed to be applied.

scholarly journals Pengaruh Kecepatan Pembentukan Tukak Lambung Terhadap Pemberian Berbagai Golongan NSAID Pada Tikus Jantan

2019 ◽  
Vol 1 (2) ◽  
pp. 8-17
Author(s):  
Parhan Parhan ◽  
Aliman Yafarugi Gulo
Keyword(s):  
Gastric Ulcer ◽  
Diclofenac Sodium ◽  
Gastric Ulcers ◽  
Dominant Factor ◽  
Epithelial Tissue ◽  
Peptic Ulcers ◽  
Epithelial Layer ◽  
Gastrointestinal Mucosa ◽  
Mucosal Layer ◽  
The Difference

Background : Gastric ulcer is wound to the mucosal layer (epithelial layer) of the stomach and mucosal irritation of 5 mm or more in diameter with depth down to submucosa. The basic pathogenesis of gastric ulcers in when there is an imbalance of aggressive factor enhancement. Non-steroidal antiinflammantory drug can cause stomach ulcers in two ways, either directly or topical irritation of the epithelial tissue and inhibit the endogeneous system of gastrointestinal mucosa of prostaglandins. In this case inhibition of prostaglandin systhesis is the dominant factor of peptic ulcers by NSAIDs. Objectives : The purpose of this study was to determine the effct of NSAID drug administration on the formation of peptic ulcers and to know the difference in the rate of formation of peptic ulcers from each class. Method : Sampel method mice performed surgery on the stomach is done in Pharmacology Laboratory of Pharmacy Institute Deli Husada Deli Tua. Results : The results of this study indicate that faster drugs cause gastric ulcers with a degree of redness are Aspirin 4.03 mm, 2.01 mm mefenamat and 1.02 mm Diclofenac Sodium while Ibuprofen mwdication does not cause peptic ulcers. Conclusion : The results of this study it can be concluded that Aspirin administration with doses of 21 mg/kg faster causes gastric ulcers from other NSAID groups such as Mefenamat with a dose of 21 mg/kg BW, Diclofenac sodium at a dose of 2 mg/kg while administration, Ibuprofen for ten days does not couse ulcers in the stomach of experimetal animals.

The Impact of Sustainability on the Value of Commercial Office Buildings in Malaysia : Russian-Doll Model Approach

2014 ◽  
Vol 71 (4) ◽  
Author(s):  
Tuti Haryati Jasimin ◽  
Hishamuddin Mohd Ali
Keyword(s):  
Supply And Demand ◽  
Office Buildings ◽  
Commercial Building ◽  
Kuala Lumpur ◽  
City Hall ◽  
Green Development ◽  
Service Oriented ◽  
The Difference ◽  
The Impact ◽  
Model Approach

The development of sustainable buildings continues to gain momentum in Malaysia due to its many benefits. The Kuala Lumpur City Hall stipulated that the construction of every commercial building must meet the requirements of green features with at least ‘GBI Gold’ level or equivalent. With the growing interest in green development, questions were raised on whether there is enhancement to the market value of green-rated properties and vice-versa. As most of the commercial office buildings are used for functions and office spaces by most organisations, they are considered a service oriented entity and can significantly benefit from having sustainability attributes. Hence, green properties are considered to be more marketable and attractive for investment purpose. However, at present, the differences in rental rates in Malaysia between green and non-green commercial office buildings are rather small. The difference is more to supply and demand factors within the specific location rather than green features factor. Therefore, this paper hopes to highlight the possible impact of economics, the environment and social attributes on the value of commercial office building incorporating with the Russian-Doll model. The highlighted sustainable attributes will provide guidance and justification in valuing real estate incorporating sustainability.

Heterogeneity of mean alveolar pressure during high-frequency oscillations

1987 ◽  
Vol 62 (1) ◽  
pp. 223-228 ◽  
Author(s):  
J. L. Allen ◽  
I. D. Frantz ◽  
J. J. Fredberg
Keyword(s):  
High Frequency ◽  
Flow Distribution ◽  
Transpulmonary Pressure ◽  
Alveolar Pressure ◽  
Regional Heterogeneity ◽  
Regional Flow ◽  
High Frequency Oscillations ◽  
Dynamic Head ◽  
Mean Pressure ◽  
The Difference

Mean alveolar pressure may exceed mean airway pressure during high-frequency oscillations (HFO). To assess the magnitude of this effect and its regional heterogeneity, we studied six excised dog lungs during HFO [frequency (f) 2–32 Hz; tidal volume (VT) 5–80 ml] at transpulmonary pressures (PL) of 6, 10, and 25 cmH2O. We measured mean pressure at the airway opening (Pao), trachea (Ptr), and four alveolar locations (PA) using alveolar capsules. Pao was measured at the oscillator pump, wherein the peak dynamic head was less than 0.2 cmH2O. Since the dynamic head was negligible here, and since these were excised lungs, Pao thus represented true applied transpulmonary pressure. Ptr increasingly underestimated Pao as f and VT increased, with Pao - Ptr approaching 8 cmH2O. PA (averaged over all locations) and Pao were nearly equal at all PL's, f's, and VT's, except at PL of 6, f 32 Hz, and VT 80 ml, where (PA - Pao) was 3 cmH2O. Remarkably, mean pressure in the base exceeded that in the apex increasingly as f and VT increased, the difference approaching 3 cmH2O at high f and VT. We conclude that, although global alveolar overdistension assessed by PA - Pao is small during HFO under these conditions, larger regional heterogeneity in PA's exists that may be a consequence of airway branching angle asymmetry and/or regional flow distribution.

scholarly journals Probing the electric field across thylakoid membranes in cyanobacteria

2019 ◽  
Vol 116 (43) ◽  
pp. 21900-21906 ◽  
Author(s):  
Stefania Viola ◽  
Benjamin Bailleul ◽  
Jianfeng Yu ◽  
Peter Nixon ◽  
Julien Sellés ◽  
...  
Keyword(s):  
Electric Field ◽  
Photosynthetic Electron Transport ◽  
Thylakoid Membranes ◽  
Transport Pathways ◽  
Electrochromic Shift ◽  
Ideal Tool ◽  
Bona Fide ◽  
The Difference ◽  
And Function

In plants, algae, and some photosynthetic bacteria, the ElectroChromic Shift (ECS) of photosynthetic pigments, which senses the electric field across photosynthetic membranes, is widely used to quantify the activity of the photosynthetic chain. In cyanobacteria, ECS signals have never been used for physiological studies, although they can provide a unique tool to study the architecture and function of the respiratory and photosynthetic electron transfer chains, entangled in the thylakoid membranes. Here, we identified bona fide ECS signals, likely corresponding to carotenoid band shifts, in the model cyanobacteria Synechococcus elongatus PCC7942 and Synechocystis sp. PCC6803. These band shifts, most likely originating from pigments located in photosystem I, have highly similar spectra in the 2 species and can be best measured as the difference between the absorption changes at 500 to 505 nm and the ones at 480 to 485 nm. These signals respond linearly to the electric field and display the basic kinetic features of ECS as characterized in other organisms. We demonstrate that these probes are an ideal tool to study photosynthetic physiology in vivo, e.g., the fraction of PSI centers that are prebound by plastocyanin/cytochrome c6 in darkness (about 60% in both cyanobacteria, in our experiments), the conductivity of the thylakoid membrane (largely reflecting the activity of the ATP synthase), or the steady-state rates of the photosynthetic electron transport pathways.

scholarly journals Differential response of alpine steppe and alpine meadow to climate warming in the central Qinghai–Tibetan Plateau

2016 ◽  
Vol 223 ◽  
pp. 233-240 ◽  
Author(s):  
Hasbagan Ganjurjav ◽  
Qingzhu Gao ◽  
Elise S. Gornish ◽  
Mark W. Schwartz ◽  
Yan Liang ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Climate Warming ◽  
Alpine Meadow ◽  
Differential Response ◽  
Alpine Steppe

Effect of Cooling Rate on the Tensile Yield Strength and Ductility Of B2 Compound in Nb-40at.% Ti-15at.%Al Alloy

1993 ◽  
Vol 322 ◽  
Author(s):  
D.-H. Hou ◽  
H.L. Fraser
Keyword(s):  
Heat Treatment ◽  
Tensile Properties ◽  
Cooling Rate ◽  
Heat Treatments ◽  
Water Quenching ◽  
Tensile Yield Strength ◽  
Dominant Factor ◽  
Al Alloy ◽  
Air Cooling ◽  
The Difference

AbstractThe effect of cooling rate on the tensile properties of specimens of the Nb-40Ti-15A1 alloy (in at.%) subjected to various heat treatments has been studied. This alloy has the B2 crystal structure and an order-disorder transition temperature between 1020°C and 1100°C. Two heat treatments have been carried out; the first one involves an 1100°C/1hr heat treatment followed by furnace cooling, air cooling or water quenching. The second type of heat treatment involves re-heating the furnace-cooled and water-quenched specimens at 400°C for 10 minutes or 900°C for 30 minutes, followed by either furnace cooling or water quenching. Tensile properties, SEM fractographs and microstructures of these specimens have been assessed. It is shown that specimens furnace-cooled from 1100°C have higher strength and less ductility than the water quenched ones. An observed microstructural feature associated with cooling rates is the difference in anti-phase domain (APD) size. Discussions are focused on possible cooling rate related phenomena that could affect the tensile properties. It is proposed that the degree of long range ordering, not the APD size, is the dominant factor for the observed cooling rate effect on the tensile properties.

Evaluation of the Dominant Factor for Electromigration in Sputtered High Purity Al Films

2010 ◽  
Vol 132 (2) ◽  
Author(s):  
X. Zhao ◽  
M. Saka ◽  
M. Yamashita ◽  
F. Togoh
Keyword(s):  
Grain Boundary ◽  
High Purity ◽  
Boundary Diffusion ◽  
Grain Boundary Diffusion ◽  
Dominant Factor ◽  
Affecting Factors ◽  
Flux Divergence ◽  
Proposed Model ◽  
Average Grain Size ◽  
The Difference

This paper is focused on evaluating the dominant factor for electromigration (EM) in sputtered high purity Al films. A closed-form equation of atomic flux divergence by treating grain boundary diffusion and hillock formation in a polycrystalline structure without passivation layer was derived to construct the theoretical model. According to the developed equation, it is available to see the effect of various parameters on the EM resistance. Moreover, based on the proposed model, we compared the EM resistance of different sputtered high purity Al films. These films differ in purity and features, which are realized as affecting factors for the EM resistance. Finally, according to the analysis by the synthesis of the obtained EM resistance, the evaluation of the dominant factor for EM in sputtered high purity Al films was approached. Although the effects of the average grain size and the effective valence cannot be ignored, the difference in diffusion coefficient was believed to have a dominant influence in determining the EM resistance. Thus, increasing the activation energy for grain boundary diffusion can significantly reduce the damage during EM in such sputtered polycrystalline Al films.

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