Spatiotemporal heterogeneity of phytoplankton diversity and its relation to water environmental factors in the southern waters of Miaodao Archipelago,China

To study the water quality influenced by the anthropogenic activities and its impact on the phytoplankton diversity in the surface waters of Miaodao Archipelago, the spatiotemporal variations in phytoplankton communities and the environmental properties of the surface waters surrounding the Five Southern Islands of Miaodao Archipelago were investigated, based on seasonal field survey conducted from November 2012 to August 2013. During the survey, a total of 109 phytoplankton species from 3 groups were identified in the southern waters of Miaodao Archipelago, of which 77 were diatoms, 29 were dinoflagellates, and 3 were chrysophytes. Species number was higher in winter（73）, moderate in autumn（70）, but lower in summer（31） and spring（27）. The species richness index in autumn（5.92） and winter（4.28） was higher than that in summer（2.83） and spring（1.41）.The Shannon-Wiener diversity index was high in autumn（2.82）, followed by winter（1.99） and summer（1.92）, and low in spring（0.07）. The species evenness index in autumn（0.46） and summer（0.39） was higher than that in winter（0.32） and spring（0.02）. On the basis of principal component analysis（PCA） and redundancy analysis（RDA）, we found that dissolved inorganic nitrogen（DIN） and chemical oxygen demand（COD） in spring, COD in summer, p H in autumn, and salinity and oil pollutant in winter, respectively, showed the strongest association with the distribution of phytoplankton diversity. The spatial heterogeneity of the southern waters of Miaodao Archipelago was quite obvious, and three zones, i.e., northeastern, southwestern and inter-island water area, were identified by cluster analysis（CA） based on key environmental variables.

Correlating plasma endothelin-1 and beta-endorphin levels to nine risk factors of acute cerebral infarction

BACKGROUND： Several studies have confirmed that endothelin and endorphin are involved in the occurrence of cerebral vasospasm. However, the correlation of these factors to acute cerebral infarction-related risk factors needs to be confirmed. OBJECTIVE： To detect endothelin-1 （ET-1） and beta-endorphin （β -EP） levels in plasma of patients with acute cerebral infarction, and to analyze the correlations of these factors to smoking, alcohol abuse, hypertension, diabetes mellitus, diseased region, diseased degree, gender, and other factors related to acute cerebral infarction. DESIGN： A case-control observation. SETTING： First Department of Neurology, Guangdong Hospital of Traditional Chinese Medicine; Department of Neurology, Second Affiliated Hospital of Sun Yat-sen University. PARTICIPANTS： Sixty-nine inpatients with acute cerebral infarction were admitted to the Department of Neurology, Second Affiliated Hospital of Sun Yat-sen University （March 2003-January 2004） and First Department of Neurology, Guangdong Hospital of Traditional Chinese Medicine （March July 2004） and recruited for this study. All 69 inpatients corresponded to the diagnosis criteria of acute cerebral infarction, formulated in the National Working Conference of Cerebrovascular Disease in 1998, and were confirmed as acute cerebral infarction by CT/MRI. The patient group consisted of 35 males [（644- 12） years old] and 34 females[ （674- 13 ） years old]. Among them, 9 patients were smokers, 7 were alcohol users, 48 had a history of hypertension, and 16 had a history of diabetes mellitus. CT/MRI examinations revealed that 35 patients presented with left focus sites, 11 with right ones and 23 with bilateral ones. Following attack, 24 patients had Barthel Index Scale grading 〈 40 points, 21 patients 40-50 points, and 24 patients 〉 60 points. An additional 59 healthy individuals, who received health examinations simultaneously, were included as controls. Among the control subjects, there were 37 males [（62±10） years old] and 22 females [（65±11） years old]. Among them, 7 patients were smokers, and 6 were alcohol users. All controls had no history of stroke, hypertension, or diabetes mellitus. Informed consents of laboratory measurements were obtained from all subjects, and this study was approved by the Hospital Ethics Committee. METHODS： ① Following admission, all subjects were scored by Barthel Index Scale （BIS） and Hamilton Depression Scale. Meanwhile, hypertension, diabetes mellitus, gender, smoking, drinking, and other conditions were recorded. CT/MRI examination was conducted to identify the focus site.②On the 2^nd day after admission, ET-1 and β -EP plasma levels were measured with an automatic ET-1 and β -EP analysis kit. MAIN OUTCOME MEASURES： ET-1 and β -EP plasma levels and their correlation to acute cerebral infarction-related factors. RESULTS： Sixty-nine patients with acute cerebral infarction, and an additional 59 healthy individuals participated in the final analysis. β ET-1 [（63.80±27.65） ng/L vs. （46.50±9.36） ng/L, P 〈 0.05] and β - EP [（94.18±33.94） mg/L vs. （51.87±23.43） mg/L, P 〈 0.05] levels of the patient group were obviously higher than respective values of the control group. ② The ET-1 and β -EP levels of patients with cerebral infarction did not correlate to hypertension, diabetes mellitus, BIS, depression, cerebral infarct focus, disease course, gender, smoking or drinking （P 〉 0.05）. CONCLUSION： The ET-I and β-EP levels of patients with acute cerebral infarction increased, but they were not obviously associated with disease course, blood pressure, blood glucose, BIS, or other common cerebral infarction-related factors.

Quantified evaluation of particle shape effects from micro-to-macro scales for non-convex grains

Particle shape plays an important role in both the micro and macro scales responses of a granular assem- bly. This paper presents a systematic way to interpret the shape effects of granular material during quasi-static shearing. A more suitable shape descriptor is suggested for the quantitative analysis of the macroscale strength indexes and contact parameters for non-convex grains, with special consid- eration given to the peak state and critical state. Through a series of numerical simulations and related post-processing analysis, particle shape is found to directly influence the strain localisation patterns, microscale fabric distributions, microscale mobilisation indexes, and probability distribution of the nor- malised contact normal force. Additionally, the accuracy of the stress-force-fabric relationship can be influenced by the average normal force and the distribution of contact vectors. Moreover, particle shape plays a more important role than do the confining pressures in determining the friction angle. Strong force chains and the dilation effect are also found to be strongly influenced by the high confinin~ oressure.