Design and implementation of low-cost geomagnetic field monitoring equipment for high-density deployment

The observation of geomagnetic field variations is an important approach to studying earthquake precursors.Since 1987,the China Earthquake Administration has explored this seismomagnetic relationship.In particular,they studied local magnetic field anomalies over the Chinese mainland for earthquake prediction.Owing to the years of research on the seismomagnetic relationship,earthquake prediction experts have concluded that the compressive magnetic effect,tectonic magnetic effect,electric magnetic fluid effect,and other factors contribute to preearthquake magnetic anomalies.However,this involves a small magnitude of magnetic field changes.It is difficult to relate them to the abnormal changes of the extremely large magnetic field in regions with extreme earthquakes owing to the high cost of professional geomagnetic equipment,thereby limiting large-scale deployment.Moreover,it is difficult to obtain strong magnetic field changes before an earthquake.The Tianjin Earthquake Agency has developed low-cost geomagnetic field observation equipment through the Beijing–Tianjin–Hebei geomagnetic equipment test project.The new system was used to test the availability of equipment and determine the findings based on big data..

Diagnosing ratio of electron density to collision frequency of plasma surrounding scaled model in a shock tube using low-frequency alternating magnetic field phase shift

A non-contact low-frequency(LF)method of diagnosing the plasma surrounding a scaled model in a shock tube is proposed.This method utilizes the phase shift occurring after the transmission of an LF alternating magnetic field through the plasma to directly measure the ratio of the plasma loop average electron density to collision frequency.An equivalent circuit model is used to analyze the relationship of the phase shift of the magnetic field component of LF electromagnetic waves with the plasma electron density and collision frequency.The applicable range of the LF method on a given plasma scale is analyzed.The upper diagnostic limit for the ratio of the electron density(unit:m^(-3))to collision frequency(unit:Hz)exceeds 1×10^(11),enabling an electron density to exceed 1×10^(20)m^(-3)and a collision frequency to be less than 1 GHz.In this work,the feasibility of using the LF phase shift to implement the plasma diagnosis is also assessed.Diagnosis experiments on shock tube equipment are conducted by using both the electrostatic probe method and LF method.By comparing the diagnostic results of the two methods,the inversion results are relatively consistent with each other,thereby preliminarily verifying the feasibility of the LF method.The ratio of the electron density to the collision frequency has a relatively uniform distribution during the plasma stabilization.The LF diagnostic path is a loop around the model,which is suitable for diagnosing the plasma that surrounds the model.Finally,the causes of diagnostic discrepancy between the two methods are analyzed.The proposed method provides a new avenue for diagnosing high-density enveloping plasma.

Hepatitis C virus G1b infection decreases the number of small low-density lipoprotein particles

AIM: To investigate how hepatitis C virus (HCV) G1b infection influences the particle number of lipoproteins.METHODS: The numbers of lipoprotein particles in fasting sera from 173 Japanese subjects, 82 with active HCV G1b infection (active HCV group) and 91 with cleared HCV infection (SVR group), were examined. Serum lipoprotein was fractionated by high-performance liquid chromatography into twenty fractions. The cholesterol and triglyceride concentrations in each fraction were measured using LipoSEARCH. The number of lipoprotein particles in each fraction was calculated using a newly developed algorithm, and the relationship between chronic HCV G1b infection and the lipoprotein particle number was determined by multiple linear regression analysis.RESULTS: The median number of low-density lipoprotein (LDL) particles was significantly lower in the active HCV group [1182 nmol/L, interquartile range (IQR): 444 nmol/L] than in the SVR group (1363 nmol/L, IQR: 472 nmol/L, P < 0.001), as was that of high-density lipoprotein (HDL) particles (14168 nmol/L vs 15054 nmol/L, IQR: 4114 nmol/L vs 3385 nmol/L, P = 0.042). The number of very low-density lipoprotein (VLDL) particles was similar between the two groups. Among the four LDL sub-fractions, the number of large LDL particles was similar between the two groups. However, the numbers of medium (median: 533.0 nmol/L, IQR: 214.7 nmol/L vs median: 633.5 nmol/L, IQR: 229.6 nmol/L, P < 0.001), small (median: 190.9 nmol/L, IQR: 152.4 nmol/L vs median: 263.2 nmol/L, IQR: 159.9 nmol/L; P < 0.001), and very small LDL particles (median: 103.5 nmol/L, IQR: 66.8 nmol/L vs median: 139.3 nmol/L, IQR: 67.3 nmol/L, P < 0.001) were significantly lower in the active HCV group than in the SVR group, respectively. Multiple linear regression analysis indicated an association between HCV G1b infection and the decreased numbers of medium, small, and very small LDL particles. However, active HCV infection did not affect the number of large LDL particles or any sub-fractions of VLDL and HDL particles.CONCLUSION: HCV G1b infection decreases the numbers of medium, small, and very small LDL particles.

Influence of Oxidized Low Density Lipoprotein on the Proliferation of Human Artery Smooth Muscle Cells in vitro

The effects of oxidized low density lipoprotein （ox-LDL） on the proliferation of cultured human vascular smooth muscle cells （vSMC） were investigated in vitro. By using NaBr density gradient centrifugation, LDL was isolated and purified from human plasma. Ox-LDL was produced from LDL by being incubated with CuSO4. ox-LDL was then added to the culture medium at different concentrations （35, 60, 85, 110, 135 and 160μg/mL） for 7 days. The influence of ox-LDL on vSMC proliferation was observed in growth curve, mitosis index, and in situ determination of apoptosis. The data were analyzed with SPSS 10.0 software. The results showed that the ox-LDL produced in vitro had a good purity and optimal oxidative degree, which was similar to the intrinsic ox-LDL in atherosclerotic plaque, ox-LDL at a concentration of 35 μg/mL demonstrated the strongest proliferation inducement, and at a concentration of 135 μg/mL, ox-LDL could inhibit the growth of vSMC. ox-LDL at concentrations of 35 and 50 μg/mL presented powerful mitotic trigger, and with the increase of ox-LDL concentration, the mitotic index of vSMC was decreased gradually, ox-LDL at higher concentrations promoted more apoptotic vSMCs, ox-LDL at lower concentrations triggered proliferation of vSMCs, and at higher concentrations induced apoptosis in vSMCs, ox-LDL played a promotional role in the pathogenesis and development of atherosclerosis by affecting vSMC proliferation and apoptosis.

Apolipoprotein B100 quality control and the regulation of hepatic very low density lipoprotein secretion

Apolipoprotein B （apoB） is the main protein component of very low density lipoprotein （VLDL） and is necessary for the assembly and secretion of these triglyceride （TG）-rich particles. Following release from the liver, VLDL is converted to low density lipoprotein （LDL） in the plasma and increased production of VLDL can therefore play a detrimental role in cardiovascular disease. Increasing evidence has helped to establish VLDL assembly as a target for the treatment of dyslipidemias. Multiple factors are involved in the folding of the apoB protein and the formation of a secretion-competent VLDL particle. Failed VLDL assembly can initiate quality control mechanisms in the hepatocyte that target apoB for degradation. ApoB is a substrate for endoplasmic reticulum associated degradation （ERAD） by the ubiquitin proteasome system and for autophagy. Efficient targeting and disposal of apoB is a regu- lated process that modulates VLDL secretion and partitioning of TG. Emerging evidence suggests that significant overlap exists between these degradative pathways. For example, the insulin-mediated targeting of apoB to autop- hagy and postprandial activation of the unfolded protein response （UPR） may employ the same cellular machinery and regulatory cues. Changes in the quality control mechanisms for apoB impact hepatic physiology and pathology states, including insulin resistance and fatty liver. Insulin signaling, lipid metabolism and the hepatic UPR may impact VLDL production, particularly during the postprandial state. In this review we summarize our current understanding of VLDL assembly, apoB degradation, quality control mechanisms and the role of these processes in liver physiology and in pathologic states.

Effects of Oxidized Low Density Lipoprotein on Transformation of Valvular Myofibroblasts to Osteoblast-like Phenotype

In order to investigate the roles of Wnt signal pathway in transformation of cardiac valvular myofibroblasts to the osteoblast-like phenotype, the primary cultured porcine aortic valve myofibroblasts were incubated with oxidized low density lipoprotein（ox-LDL, 50 mg/L）, and divided into four groups according to the ox-LDL treatment time： control group, ox-LDL 24-h group, ox-LDL 48-h group, and ox-LDL 72-h group. Wnt signal pathway blocker Dickkopf-1（DDK-1, 100 μg/L） was added in ox-LDL 72-h group. The expression of α-smooth muscle actin（α-SMA）, bone morphogenetic protein 2（BMP2）, alkaline phosphatase（ALP）, and osteogenic transcription factor Cbfa-1 was detected by Western blotting, and that of β-catenin, a key mediator of Wnt signal pathway by immunocytochemical staining method. The Wnt/β-catenin was observed and the transformation of myofibroblasts to the osteoblast-like phenotype was examined. The expression of α-SMA, BMP2, ALP and Cbfa-1 proteins in the control group was weaker than in the ox-LDL-treated groups. In ox-LDL-treated groups, the protein expression of α-SMA, BMP2, ALP, and Cbfa-1 was significantly increased in a time-dependent manner as compared with the control group, and there was significant difference among the three ox-LDL-treated groups（P〈0.05 for all）; β-catenin protein was also up-regulated in the ox-LDL-treated groups in a time-dependent manner as compared with the control group（P〈0.05）, and its transfer from cytoplasm to nucleus and accumulation in the nucleus were increased in the same fashion（P〈0.05）. After addition of DKK-1, the expression of α-SMA, bone-related proteins and β-catenin protein was significantly reduced as compared with ox-LDL 72-h group（P〈0.05）. The Wnt/ β-catenin signaling pathway may play an important role in transformation of valvular myofibroblasts to the osteoblast-like phenotype.

Expression of Monocyte Chemoattractant Protein-1 in Monocytes and Effects of Native and Oxidized Very Low Density Lipoproteins

Monocyte chemoattractant protein-1(MCP-1), a potent chemoattractant, is thought to play an important role in migration of monocytes into atherosclerotic lesions. The present study was designed to investigate the capacity of human peripheral blood monocytes to express MCP-1 and effects of native very low density lipoprotein (VLDL) and oxidized VLDL(OX-VLDL) on the expression. The total RNA was extracted from cultured monocytes, which were exposed to VLDL and OX-VLDL, and the media conditioned by monocytes were collected. MCP-1 mRNA expression was examined by Northern blot analysis. MCP-1 protein in conditioned media was determined by using sandwich ELISA. The results showed that monocytes can express MCP-1 after a 24 h incubation at 37℃，and the expression was markedly increased by a exposure to OX-VLDL, whereas the expression was slightly increased when exposed to VLDL. It suggests that the capacity of monocytes to produce MCP-1 that recruits and activates circulating monocytes may be of considerable importance in atherogenesis, and oxidation of VLDL enhances its potential to promote atherogenesis.

INVESTIGATION ON THE DENSITY UNIFORMITY OF PRESSED PARTS BY LOW-VOLTAGE ELECTROMAGNETIC COMPACTION

Powder metallurgy is an efficient approach to fabricate varieties of high performance structure materials, function materials and special materials working under limited conditions. Research and development of new efficient technology to form high-density, high-performance and net shape parts is a key to widen application and development of powder materials. Recently, the low-voltage electromagnetic compaction (EMC) has been used by present authors to compacted copper, tin, aluminum powders and the products with 99% relative density have been acquired. In this work, the research has been extended to investigation on the density uniformity of pressed parts. The analysis results show that the density of the part compacted by low-voltage EMC decreases gradually in press direction as static compaction. But it is higher and more homogeneous. The density of the top part increases gradually from the center to the outer, which is just reversal of the bottom part. In some extent, the higher the discharging voltage is, the higher the density is and the more homogeneous the distribution is. In addition, repetitive compaction can improve the density of powder parts and the distribution uniformity.

Function and Significance of Very Low Density Lipoprotein Receptor Subtype Ⅱ

To explore the functions of very low density lipoprotein receptor (VLDL-R) subtype II in lipoprotein metabolism and foam cells formation, the recombinant plasmid with the two subtypes cDNA was constructed respectively, the ldl-A7 cell lines were transfected and two cell lines expressing VLDL-R were obtained: one stably expressing the VLDLR with the O-linked sugar region (type I VLDLR) and the other without the O-linked sugar region (type II VLDLR). In the study on binding of VLDLR to their nuclein labeled natural ligands (VLDL and β-VLDL), it was found that surface binding of 125I-VLDL or 125I-β-VLDL of ldl-A7 cells transfected with type I VLDLR recombinant (ldl-A7-VRI) was more higher than that of ldl-A7 cells transfected with type II VLDLR recombinant (ldl-A7-VRII). After being incubated with VLDL for different time, the contents of triglyceride and total cholesterol in cells were mensurated, and the formation of foam cells and accumulation of lipid in cells was observed by oil-red O staining. The results showed that the contents of triglyceride and total cholesterol in ldl-A7-VR I were much higher than those in ldl-A7-VR II, and ldl-A7-VR I could transform into foam cells notably. It was suggested that type I VLDLR binds with relative higher affinity to VLDL and β-VLDL, and internalizes much more lipoprotein into cells. As a result, we can conclude that type I VLDLR plays a more important role in lipoprotein metabolism and foam cells formation than type II VLDLR.

Data Gathering in Wireless Sensor Networks Via Regular Low Density Parity Check Matrix

A great challenge faced by wireless sensor networks(WSNs) is to reduce energy consumption of sensor nodes. Fortunately, the data gathering via random sensing can save energy of sensor nodes. Nevertheless, its randomness and density usually result in difficult implementations, high computation complexity and large storage spaces in practical settings. So the deterministic sparse sensing matrices are desired in some situations. However,it is difficult to guarantee the performance of deterministic sensing matrix by the acknowledged metrics. In this paper, we construct a class of deterministic sparse sensing matrices with statistical versions of restricted isometry property(St RIP) via regular low density parity check(RLDPC) matrices. The key idea of our construction is to achieve small mutual coherence of the matrices by confining the column weights of RLDPC matrices such that St RIP is satisfied. Besides, we prove that the constructed sensing matrices have the same scale of measurement numbers as the dense measurements. We also propose a data gathering method based on RLDPC matrix. Experimental results verify that the constructed sensing matrices have better reconstruction performance, compared to the Gaussian, Bernoulli, and CSLDPC matrices. And we also verify that the data gathering via RLDPC matrix can reduce energy consumption of WSNs.

Obstructive jaundice leads to accumulation of oxidized low density lipoprotein in human liver tissue

Oxidized low density lipoprotein （ox-LDL） molecule is one of the most important modified lipoproteins produced during the oxidative stress. Modified lipoproteins have been defined as being part of the immune inflammatory mechanisms in association with oxidant stress. We have reported the accumulation of ox-LDL in Balb/c mice liver after bile duct ligation previously. Here, we investigated this finding in human beings with obstructive jaundice. Our study demonstrates that obstructive jaundice results in tremendous accumulation of ox-LDL in the liver tissue of patients.

Oxidized low density lipoprotein (Ox-LDL) impacts on erythrocyte viscoelasticity and its molecular mechanism

Aim:The oxidized low-density lipoprotein(OxLDL) plays an important role in atherosclerosis yet it remains unclear if it damages circulating erythrocytes. Method: In this study。

The role of low-density lipoprotein （LDL） and high-density lipoprotein （HDL） in comparison with whole egg yolk for sperm cryopreservation in rhesus monkeys

Low-density lipoprotein （LDL） extracted from hen egg yolk has recently been considered to be superior to whole egg yolk in sperm cryopreservation of various animal species. Meanwhile, there was a notion that high-density lipoprotein （HDL） in egg yolk may have a negative effect on post-thaw survival. The role of LDL and HDL in sperm cryopreservation of rhesus monkeys has not been explored. The present study evaluates their effect in comparison with egg yolk with or without the addition of permeable cryoprotectant （glycerol） on sperm cryopreservation of rhesus macaques. In addition, various additives intended to change the lipid composition of LDL-sperm membrane complex have also been tested for their effectiveness in preserving post-thaw viability. Our findings indicated that LDL is the main component in egg yolk that is responsible for its protective role for sperm cryopreservation in rhesus monkeys. Regardless of the presence or absence of glycerol, the protective role of LDL is similar to that of egg yolk and we did not observe any superiority in post-thaw survival with LDL when compared to egg yolk. Modifying the lipid composition of LDL-sperm membrane complex with the addition of cholesterol, cholesterol loaded cyclodextrin and phosphatidylcholine also did not yield any improvements in pest-thaw survival; while addition of methyl-β-cyclodextrin reduced post-thaw motility. HDL plays a neutral role in sperm cryopreservation of rhesus monkeys. The present study suggests that egg yolk may still hold advantages when compared with LDL as effective components in extenders for sperm cryopreservation in rhesus monkeys.

Role of PERK/eIF2α/CHOP Endoplasmic Reticulum Stress Pathway in Oxidized Low-density Lipoprotein Mediated Induction of Endothelial Apoptosis

Objective PERK/elF2/CHOP is a major signaling pathway mediating endoplasmic reticulum （ER） stress related with atherosclerosis. Oxidized LDL （ox-LDL） also induces endothelial apoptosis and plays a vital role in the initiation and progression of atherosclerosis. The present study was conducted to explore the regulatory effect of ox-LDL on PERK/elF2a/CHOP signaling pathway in vascular endothelial cells. Methods The effects of ox-LDL on PERK and p-elF2a protein expression of primary human umbilical vein endothelial cells （HUVECs） were investigated by Western blot analysis. PERK gene silencing and selective elF2a phosphatase inhibitor, salubrinal were used to inhibit the process of ox-LDL induced endothelial cell apoptosis, caspase-3 activity, and CHOP mRNA level. Results Ox-LDL treatment significantly increased the expression of PERK, PERK-mediated inactivation of elF2a phosphorylation, and the expression of CHOP, as well as the caspase-3 activity and apoptosis. The effects of ox-LDL were markedly decreased by knocking down PERK with stable transduction of lentiviral shRNA or by selective elF2a phosphatase inhibitor, salubrinal. Conclusion This study provides the first evidence that ox-LDL induces apoptosis in vascular endothelial cells mediated largely via the PERK/elF2a/CHOP ER-stress pathway. It adds new insights into the molecular mechanisms underlying the pathogenesis and progression of atherosclerosis.

Fluorobenzene diluted low-density electrolyte for high-energy density and high-performance lithium-sulfur batteries

The mass fraction of electrolytes is the crucial factor affecting the energy density of lithium-sulfur(Li-S)batteries. Due to the high porosity within the C/S cathode, high concentration of polysulfides, and side reaction in lithiun metal anode under lean electrolyte, it is extremely challenging to improve performance while reducing the electrolyte volume. Here, we report a novel electrolyte with relatively low density(1.16 g cm^(-2)), low viscosity(1.84 m Pa s), and high ionic conductivity, which significantly promotes energy density and cyclability of Li-S batteries under practical conditions. Moreover, such electrolyte enables a hybrid cathode electrolyte interphase(CEI) and solid electrolyte interface(SEI) layer with plentiful Li F, which leads to fast kinetics of ions transport and stable cyclability even under low temperatures.Compared to Li-S batteries in electrolyte employing 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether(TTE) diluent, the ultra-thick cathode(20 mg cm^(-2)) shows a high capacity of 9.48 m Ah cm^(-2)and excellent capacity retention of 80.3% over 191 cycles at a low electrolyte-to-sulfur ratio(E/S = 2) and negative-to-positive capacity ratio(N/P = 2.5), realizing a 19.2% improvement in energy density in coin cells(from 370 to 441 Wh kg^(-1)) and a high energy density up to 467 Wh kg^(-1) in pouch cells. This study not only provides guidance for the electrolyte design but also paves the way for the development of high performance Li-S batteries under practical conditions.

Density functional theory calculations of tetracene on low index surfaces of copper crystal

This paper carries out the density functional theory calculations to study the adsorbate-substrate interaction between tetracene and Cu substrates （Cu （110） and Cu （100） surface）. On each of the surfaces, two kinds of geometry are calculated, namely ＇flat-lying＇ mode and ＇upright standing＇ mode. For ＇flat-lying＇ geometry, the molecule is found to be aligned with its longer molecular axis along close-packed direction of the substrate surfaces. For ＇upright standing＇ geometry, the long axis of tetracene is found to be parallel to the surface normal of the substrate on Cu （110） surface. However, tetracene appears as ＇tilted＇ mode on Cu （100） surface. Structures with ＇flat-lying＇ mode have much larger adsorption energy and charge transfer upon adsorption than that with ＇upright standing＇ mode, indicating the preference of ＇flat-lying＇ geometry on both Cu （110） and Cu （100） surface.

Implementation of low-density parity-check codes decoder for CCSDS standard

The complexity/performance balanced decoder for low-density parity-check （LDPC） codes is preferred in practical wireless communication systems. A low complexity LDPC decoder for the Consultative Committee for Space Data Systems （CCSDS） standard is achieved in DSP. An ap- proximate decoding algorithm, normalized rain-sum algorithm, is used in the implementation for its low amounts of computation. To reduce the performance loss caused by the approximation, the pa- rameters of the normalized min-sum algorithm are determined by calculating and finding the mini- mum value of thresholds through density evolution. The minimum value which indicates the best per- formance of the decoding algorithm is corresponding with the optimized parameters. In implementa- tion, the memory cost is saved by decomposing the parity-check matrix into submatrices to store and the computation of passing message in decoding is accelerated by using the intrinsic function of DSP. The performance of the decoder with optimized factors is simulated and compared with the ideal BP decoder. The result shows they have about the same performance.

Flame retardancy effect of surface-modified metal hydroxides on linear low density polyethylene

Metal hydroxides （MAH） consisting of magnesium hydroxide and aluminum hydroxide with a mass ratio of 1：2 were surface-modified by y-diethoxyphosphorous ester propyldiethoxymethylsilane, boric acid and diphenylsilanediol in xylene under dibutyl tin dilaurate catalyst at 140 ℃. Phosphorus, silicon and boron elements covalently bonded to metal hydroxide particles were detected by X-ray photoelectron spectroscopy. The degradation behavior of the surface-modified MAH was characterized by thermogravimetric analysis. The results show that linear low density polyethylene （LLDPE） composite, filled with 50% （mass fraction） of MAH modified by 5.0% （mass fraction） of modifiers, passes the V-0 rating of UL-94 test and shows the limited oxygen index of 34%, and its heat release rate and average effective heat combustion in a cone calorimeter measurement decrease obviously; The mechanical properties of MAH can be improved by surface-modification. The uniform dispersion of particles and strong interfacial bonding between particles and matrix are obtained.

Development of Surface Grating Distributed Feedback Quantum Cascade Laser for High Output Power and Low Threshold Current Density

We report on the room-temperature cascade laser （QCL） at λ -4.7μm. cw operation of a surface grating Both grating design and material distributed feedback （DFB） quantum optimization are used to decrease the threshold current density and to increase the output power. For a high-reflectivity-coated 13-μm-wide and 4- mm-long laser, high wall-plug efficiency of 6% is obtained at 20℃ from a single facet producing over I W of ew output power. The threshold current density of DFB QCL is as low as 1.13kA/cm^2 at 10℃ and 1.34kA/cm2 at 30℃ in cw mode. Stable single-mode emission with a side-mode suppression ratio of about 30 dB is observed in tile working temperature range of 20-50℃.

Relationship between the low density lipoprotein receptor gene polymorphism and serum lipid levels in the Guangxi Bai Ku Yao population

Objectives Bai Ku Yao(White-trousers Yaos)is a special branch of Yao minority in China.They are now living in both Lihu and Baxu villages,Nandan County, Guangxi,China.The population size is about 30,000.The special customs and culture of Bai Ku Yao,including their special clothing,intra-ethnic marriages and alcohol intake are still completely conserved to the present day.In previous epidemiologic studies,we found that the serum lipid levels and the prevalence of hyperlipidaemia were lower in Bai Ku Yao than in Han Chinese from the same region.This ethnic difference in serum lipid profiles is still not well known.We hypothesized that there may be significant differences in some genetic polymorphismsssociation of low density lipoprotein receptor (LDL-R) genepolymorphism and several environmental factors with serum lipid levels in the Guangxi Bai Ku Yao and Han populations.Methods A total of 1024 subjects of Bai Ku Yao and 792 participants of Han Chinese were stud- ied by a stratified randomized cluster sampling.Epidemiological survey was carried out using internationally standardized methods.Information on demographics,socioeconomic status, and lifestyle factors was collected with standardized questionnaires. The height,weight,waist circumference,blood pressure, and serum total cholesterol(TC),triglyceride(TG), high-density lipoprotein cholesterol(HDL-C),low-density lipoprotein cholesterol(LDL-C),apolipoprotein(Apo) A1, and ApoB were measured.Body massindex(BMI,kg/m2) was calculated.Genotyping of the LDL-RAvaⅡwas performed by polymerse chain reaction and restriction fragment length polymorphism combined with gel electrophoresis,and then confirmed by direct sequencing.Results(l)The height,weight,serum TC,HDL-C,LDL-C,ApoAl levels and the ratio of ApoAl to ApoB were lower in Bai Ku Yao than in Han Chinese(P【0.01 for all),whereas the percentage of subjects who consumed alcohol or smoked cigarettes was higher in Bai Ku Yao than in Han Chinese(P【0.01 for each).(2) The frequency of A+ allele in Bai Ku Yao was 34.5%,and the frequencies of A-A-,A-A+ and A+A + genotypes were 42.6%,45.9%and 11.5%;respectively. The frequency of A+ allele in Han Chinese was 19.3%(P【0.001),and the frequencies of A-A-,A-A + and A+A+ genotypes were 64.9%,31.6%and 3.5%(P【0.001);respectively. The frequencies of A-A-,A-A+ and A+A+ genotypes in Bai Ku Yao were significant difference between males and females,between normal TC and high TC subgroup, and between normal LDL-C and high LDL-C subgroup (P【0.05 for all),whereas the frequencies of A- and A+ ? alleles in Han Chinese were significant difference between males and females(P【0.05).(3) Serum LDL-C levels in Bai Ku Yao were significant difference among the A-A-, A-A+ and A+A+ genotypes(P【0.05),the A+ carriers had higher serum LDL-C levels.Serum HDL-C levels in Han Chiese were significant difference among the A-A-,A-A + and A+A+ genotypes(P【0.01),the A+ carriers had higher serum HDL-C levels.(4) After adjusting other factors,the prevalence of LDL-C abnormality was still higher in Han Chiese than in Bai Ku Yao.The prevalence of TC abnormality in Han Chinese was almost twice high as in Bai Ku Yao. The age and diet were common risk factor for TC abnormality. No effect of AvaⅡgenotype or alcohol consumption on the TC abnormality was found,but the combination of geno-type and alcohol consumption can increase the prevalence of TC abnormality[Exp(B) =(1.154)].Age was negatively cor- related with TG level.Conclusions Serum TC and LDL-C levels were lower in Bai Ku Yao than in Han Chinese.There were significant differences in the AvaⅡallele and genotype frequencies between the he A+ carriers in Bai Ku Yao had higher serum LDL-C levels,whereas the A+ carriers in Han had higher serum HDL-C levels.Interactions between alcohol consumption or cigarette smoking and the LDL-R AvaⅡgenotype were also observed.The differences in the serum lipid profiles between the two ethnic groups might partly result from different genotypic frequency of LDL-R AvaⅡpolymorphism or differentgene-enviromental interactions.Bai Ku Yao and Han population,the frequency of A + allele was higher in Bai Ku Yao than in Han.T between the two ethnic groups.Therefore,the aim of the present study was to detect the