The Estimation of the Probability of the Twin Crisis Occurrence

This paper calculates the probability of the twin crisis by empirical analysis with models of Logit and Probit. It selects some countries where twin crisis occurred in 1997 as samples, and forecasts within the samples. Then, it selects some countries where twin crisis occurred in 2008, and tests from outside samples. Results show that the model was well fitted and of high accuracy. The empirical results show that when economy growing too fast, a country should prevent the formation of the bubble economy; the excessive expansion of domestic credit will create bubble economy; variables of banking crisis tend to be as simultaneous or warning indicators for the occurrence of currency crisis. Structure of foreign debt must be suitable and the scale of foreign exchange reserves must be moderate. Key words: Banking crisis; Currency crisis; Twin crisis; Probability measuremen

Spatiotemporal Scan and Age-Period-Cohort Analysis of Hepatitis C Virus in Henan, China: 2005–2012

Background: Studies have shown that hepatitis C virus (HCV) infection increased during the past decades in China. However, little evidence is available on when, where, and who were infected with HCV. There are gaps in knowledge on the epidemiological burden and evolution of the HCV epidemic in China. Methods: Data on HCV cases were collected by the disease surveillance system from 2005 to 2012 to explore the epidemic in Henan province. Spatiotemporal scan statistics and age-period-cohort (APC) model were used to examine the effects of age, period, birth cohort, and spatiotemporal clustering. Results: 177,171 HCV cases were reported in Henan province between 2005 and 2012. APC modelling showed that the HCV reported rates significantly increased in people aged > 50 years. A moderate increase in HCV reported rates was observed for females aged about 25 years. HCV reported rates increased over the study period. Infection rates were greatest among people born between 1960 and 1980. People born around 1970 had the highest relative risk of HCV infection. Women born between 1960 and 1980 had a five-fold increase in HCV infection rates compared to men, for the same birth cohort. Spatiotemporal mapping showed major clustering of cases in northern Henan, which probably evolved much earlier than other areas in the province. Conclusions: Spatiotemporal mapping and APC methods are useful to help delineate the evolution of the HCV epidemic. Birth cohort should be part of the criteria screening programmes for HCV in order to identify those at highest risk of infection and unaware of their status. As Henan is unique in the transmission route for HCV, these methods should be used in other high burden provinces to help identify subpopulations at risk

Cadmium phytotoxicity: issues, progress, environmental concerns and future perspectives

Cadmium, a high toxicity element, is a potential threat to plant and human health, and a dangerous pollutant in the environment. Uptake and accumulation by crops represent the main entry pathway for potentially health-threatening toxic metals into human and animal food. Crops and other plants take up Cd from the soil or water and may distribute it in their roots and shoots. Soil and/or water are usually contaminated with Cd through natural sources, industrial effluent, and anthropogenic activities. In this review, the sources of Cd contamination, evaluation of the phytotoxic effects on plants, and mode of action of Cd toxicity, were summarized. Plant defensive strategies upon excess Cd are also considered in this review. Cd-induced effects include oxidative stress, disintegration of the photosynthetic apparatus, reduction in gas exchange parameters, nutrient imbalance, and subcellular organelle degradation. In addition, Cd severely impairs biomolecules such as DNA, protein, and lipids. Although plants are sessile in nature, they are equipped with certain mechanisms to cope with unfavorable conditions. These mechanisms include synthesis of metal-helating proteins, expression of enzymatic and non-enzymatic antioxidants, organic acids, and plant root–mycorrhiza association. The built-in system of plant tolerance to Cd can be further enhanced by the application of exogenous organic and inorganic metal sources. This review will broaden the knowledge about the Cd accumulation in plants and the responses to metal exposure, as well as our understanding of metal tolerance and overcoming this serious issue for sustainable agriculture and human health worldwide. Highlights Cd accumulation has harmful effects in an organism. Cd has been listed 7th out of 275 compounds in the priority list of hazardous materials. Cd remains in the soil for 15–1100 years. Plants usually imply certain strategies to overcome Cd toxicity. Plants built-in systems can be enhanced to overwhelmed this problem.Cadmium, a high toxicity element, is a potential threat to plant and human health, and a dangerous pollutant in the environment. Uptake and accumulation by crops represent the main entry pathway for potentially health-threatening toxic metals into human and animal food. Crops and other plants take up Cd from the soil or water and may distribute it in their roots and shoots. Soil and/or water are usually contaminated with Cd through natural sources, industrial effluent, and anthropogenic activities. In this review, the sources of Cd contamination, evaluation of the phytotoxic effects on plants, and mode of action of Cd toxicity, were summarized. Plant defensive strategies upon excess Cd are also considered in this review. Cd-induced effects include oxidative stress, disintegration of the photosynthetic apparatus, reduction in gas exchange parameters, nutrient imbalance, and subcellular organelle degradation. In addition, Cd severely impairs biomolecules such as DNA, protein, and lipids. Although plants are sessile in nature, they are equipped with certain mechanisms to cope with unfavorable conditions. These mechanisms include synthesis of metal-helating proteins, expression of enzymatic and non-enzymatic antioxidants, organic acids, and plant root–mycorrhiza association. The built-in system of plant tolerance to Cd can be further enhanced by the application of exogenous organic and inorganic metal sources. This review will broaden the knowledge about the Cd accumulation in plants and the responses to metal exposure, as well as our understanding of metal tolerance and overcoming this serious issue for sustainable agriculture and human health worldwide. Highlights Cd accumulation has harmful effects in an organism. Cd has been listed 7th out of 275 compounds in the priority list of hazardous materials. Cd remains in the soil for 15–1100 years. Plants usually imply certain strategies to overcome Cd toxicity. Plants built-in systems can be enhanced to overwhelmed this problem

Crystal structure and biochemical analyses reveal Beclin 1 as a novel membrane binding protein

The Beclin 1 gene is a haplo-insufficient tumor suppressor and plays an essential role in autophagy. However, the molecular mechanism by which Beclin 1 functions remains largely unknown. Here we report the crystal structure of the evolutionarily conserved domain (ECD) of Beclin 1 at 1.6 Å resolution. Beclin 1 ECD exhibits a previously unreported fold, with three structural repeats arranged symmetrically around a central axis. Beclin 1 ECD defines a novel class of membrane-binding domain, with a strong preference for lipid membrane enriched with cardiolipin. The tip of a surface loop in Beclin 1 ECD, comprising three aromatic amino acids, acts as a hydrophobic finger to associate with lipid membrane, consequently resulting in the deformation of membrane and liposomes. Mutation of these aromatic residues rendered Beclin 1 unable to stably associate with lipid membrane in vitro and unable to fully rescue autophagy in Beclin 1-knockdown cells in vivo. These observations form an important framework for deciphering the biological functions of Beclin 1

The Pressure Enhances the Extraction Yield of Total Triterpenoids from Ganoderma Lucidum

The high pressure used as a single factor was applied to extract triterpenoids from ganoderma lucidum. In this paper, the conditions of HPCL-Recator extraction were optimized, the optimum extraction parameters were respectively as following: 90°C, 1Mpa, 30min, 50ml/g, 70% (v/v) ethanol, and the highest extraction yield of triterpenoids reached 1.41% (mg/g). Ultrasonic-assited extraction (UAE), microwave-assisted extraction (MAE) were also optimized, and the the highest extraction yield were 1.08% and 1.21%. The results showed that the high pressure extraction is more efficient than the conventional UAE and MAE

Extraction, Structural Characterization, and Potential Antioxidant Activity of the Polysaccharides from Four Seaweeds

Four seaweed polysaccharides were extracted from Sarcodia ceylonensis, Ulva lactuca L., Gracilaria lemaneiformis, and Durvillaea antarctica, respectively, by microwave-assisted extraction. The effect of three significant variables (extraction time, extraction temperature, and the ratio of water to raw material) on the process for extracting polysaccharides was investigated, along with the optimization of the extraction using the response surface method (RSM) with a Box–Behnken design. The polysaccharide structure, monosaccharide composition, degree of sulfation, and molecular weight (MW) distribution were analyzed by infrared (IR) spectrometry, gas chromatography (GC), and high-performance gel permeation chromatography (HPGPC). IR spectrometry showed that Sarcodia ceylonensis polysaccharide (SCP), Ulva lactuca L. polysaccharide (ULLP), and Durvillaea antarctica polysaccharide (DAP) were all sulfated polysaccharides and, except Gracilaria lemaneiformis polysaccharide (GLP), all belong to β-pyranosidic polysaccharides. The average molecular weight (MW) of SCP, ULLP, GLP, and DAP was 466, 404, 591, and 482 kDa, respectively. The quantitative and comparative results with external standards indicated that the main monosaccharide in SCP and ULLP was mannose; and GLP and DAP were mainly composed of galactose and glucose, respectively. Then the in vitro antioxidant activity of all of the polysaccharides was evaluated using different assays—2,2–azino –bis (3-ethylbenzthiazoline-6- sulfonate) (ABTS), hydroxyl radical, nitrite scavenging capacity, and reducing power—and the relationship between their antioxidant activity and chemical characteristics were also examined. ULLP presented the highest ABTS radical scavenging activity; ULLP, SCP and DAP also showed a strong effect on the ABTS radical scavenging activity. SCP and ULLP exhibited excellent hydroxyl radical scavenging activities, about 83.33% ± 2.31% and 80.07% ± 2.17%, respectively, at 4 mg/mL. The reducing power of DAP was relatively more pronounced than that of the three other polysaccharides. However, the nitrite scavenging activities of the four seaweed polysaccharides were weaker than other antioxidant activity (ABTS), hydroxyl radical scavenging capacity, and reducing power. In addition, GLP exhibited lower activities than the other three samples in all of the tests for the antioxidant activity

A Fast and Cost-Effective Detection of Melamine by Surface Enhanced Raman Spectroscopy Using a Novel Hydrogen Bonding-Assisted Supramolecular Matrix and Gold-Coated Magnetic Nanoparticles

A fast and cost-effective melamine detection approach has been developed based on surface enhanced Raman spectroscopy (SERS) using a novel hydrogen bonding-assisted supramolecular matrix. The detection utilizes Fe3O4/Au magnetic nanoparticles coated with 5-aminoorotic acid (AOA) as a SERS active substrate (Fe3O4/Au–AOA), and Rhodamine B (RhB) conjugated AOA as a Raman reporter (AOA–RhB). Upon mixing the reagents with melamine, a supramolecular complex [Fe3O4/Au–AOA•••melamine•••AOA–RhB] was formed due to the strong multiple hydrogen bonding interactions between AOA and melamine. The complex was separated and concentrated to a pellet by an external magnet and used as a supramolecular matrix for the melamine detection. Laser excitation of the complex pellet produced a strong SERS signal diagnostic for RhB. The logarithmic intensity of the characteristic RhB peaks was found to be proportional to the concentration of melamine with a limit of detection of 2.5 µg/mL and a detection linearity range of 2.5~15.0 µg/mL in milk. As Fe3O4 nanoparticles and AOA are thousands of times less expensive than the monoclonal antibody used in a traditional sandwich immunoassay, the current assay drastically cut down the cost of melamine detection. The current approach affords promise as a biosensor platform that cuts down sample pre-treatment steps and measurement expense

Preparation and Evaluation of Microcapsules Encapsulating Royal Jelly Sieve Residue: Flavor and Release Profile

This study aimed to improve the flavor of royal jelly residue via microencapsulation technology using Arabic gum and gelatin as wall materials. This microencapsulation technology showed a good encapsulation yield of 85.71 ± 2.84% and encapsulation efficiency of 92.34 ± 3.17%. The intact structures of the microcapsules were observed using optical and scanning electron microscopes. The results of the simulated gastrointestinal digestion proved that the microcapsules were well-tolerated in the gastric environment (a release rate of 32.95 ± 2.34%). Both electronic nose and electronic tongue evaluations showed that microencapsulation improved the sensory index of the royal jelly sieve residue. After microencapsulation, the astringency, bitterness, and irritant odors of the royal jelly residue were reduced. Simultaneously, the release rate in the intestine was 98.77 ± 1.91%, which demonstrated that microencapsulation would not prevent the human body from absorbing the royal jelly. The results from this study are expected to facilitate the development of mild flavor products made from royal jelly

Effects of Partial Desulfation on Antioxidant and Inhibition of DLD Cancer Cell of Ulva Fasciata Polysaccharide

Ulva fasciata belonging to the family Ulvaceae, commonly known as ‘sea lettuce’, is an abundantly growing green seaweed in coastal seashore of South China. Three different molecular weight sulfated polysaccharides (UFP1, UFP2 and UFP3) were extracted and separated from U. fasciata by hot water extraction and ultrafiltration. The three native UFP fractions had partial desulfurization by solvolytic desulfation respectively and the effect of sulfate content on the exhibition of the antioxidant and anti-tumor capacities had been evaluated and compared. The results showed that each native polysaccharide (UFP1, UFP2, UFP3) with high sulfate content exhibited better antioxidant activities compared with the partial desulfated polysaccharides (DS-UFP1, DS-UFP2, DS-UFP3). Specifically, UFP2 with relatively high sulfate content, molecular weight and uronic acid content had consistently excellent antioxidant performances. However, UFP2 demonstrated the minimal inhibitory effects on growth of DLD intestinal cancer cells. Instead, DS-UFP3 with the lowest sulfate content but highest uronic acid content and molecular weight exhibited the best antitumor activity