[Hydrochemical Characteristics and Controlling Factors of Groundwater in the Leizhou Peninsula].

Groundwater resources in the Leizhou Peninsula provide a strong support for the economic and social development. Therefore, understanding the chemical characteristics and formation mechanism of groundwater in this area is necessary for the rational exploitation and sustainable utilization of water resources. In this study, 43 groundwater samples were collected, and the hydrochemical characteristics and controlling factors were analyzed by descriptive statistical analysis, Piper triangular diagrams, ArcGIS spatial interpolation, Gibbs diagram, and ion ratios. The results showed that:① The anions and cations of the groundwater in the study area were mainly HCO3-, Ca2+, and Na+, and the hydrochemical types were mainly HCO3-Cl-Na-Ca, HCO3-Cl-Na-Ca-Mg, HCO3-Cl-Na-Mg, and HCO3-Na. The contents of Cl-, SO42-, and Na+were higher in the west of Leizhou City compared to other areas. The sites with higher contents of HCO3-, NO3-, Ca2+, Mg2+, and K+ were mainly concentrated in the southwest and eastern coastal areas. ② The chemical evolution of groundwater was mainly affected by water-rock interaction, cation alternating adsorption, and anthropogenic activities. The sources of Na+ and K+ were mainly from evaporative and silicate rocks, Ca2+ and Mg2+ were mainly from carbonate karstification, while NO3- originated from anthropogenic activities.

[Source Analysis and Health Risk Assessment of Heavy Metals in Groundwater of Leizhou Peninsula].

Source identification and health risk assessment of heavy metals in groundwater is one of the key issues in China's new era of environmental management. In order to reveal the status, sources, and health risk of pollutants in groundwater of the Leizhou Peninsula, 44 groundwater samples were collected, and the concentrations and spatial distribution of Cr, Mn, Cu, Zn, As, Cd, Hg, and Pb were measured and analyzed. The sources of heavy metals in groundwater were then determined through correlation coefficient and principal component analysis. Finally, the health risk model was used to evaluate the different health risks associated with these heavy metals. The results showed that the average value of heavy metal elements in groundwater of the Leizhou Peninsula does not inferior to the class Ⅱ water quality standard(GB/T 14848-2017). However, As, Mn, and Cd do not meet the standard. The overall spatial distribution indicated obvious spatial differences, with higher values in the south than in the north. Heavy metal sources can be identified as three principal components (PCs). PC1 (Cu, Zn, Cd, and Pb) metals mainly originate from industrial, agricultural, and traffic sources. PC2 (Cr, Mn, and As) sources can be both natural and man-made, and PC3 (Hg) sources are primarily man-made. For the groundwater of the Leizhou Peninsula, the health risks of 8 metals are with the acceptable range, the carcinogenic risk of adults is higher than that of children, and the risk of drinking exposure is higher than that of skin exposure. The study shows that the environmental protection department should encourage the rational exploitation of groundwater resources and control the sources of pollution to reduce health risks.

Progress of crystallization in microfluidic devices.

Microfluidic technology provides a unique environment for the investigation of crystallization processes at the nano or meso scale. The convenient operation and precise control of process parameters, at these scales of operation enabled by microfluidic devices, are attracting significant and increasing attention in the field of crystallization. In this paper, developments and applications of microfluidics in crystallization research including: crystal nucleation and growth, polymorph and cocrystal screening, preparation of nanocrystals, solubility and metastable zone determination, are summarized and discussed. The materials used in the construction and the structure of these microfluidic devices are also summarized and methods for measuring and modelling crystal nucleation and growth process as well as the enabling analytical methods are also briefly introduced. The low material consumption, high efficiency and precision of microfluidic crystallizations are of particular significance for active pharmaceutical ingredients, proteins, fine chemicals, and nanocrystals. Therefore, it is increasingly adopted as a mainstream technology in crystallization research and development.

Comparative analysis of intestinal parasitic infections of outpatients in Guangxi medical university affiliated hospital in 2005 and 2013.

OBJECTIVE: To understand the hospital's status and trends of intestinal parasitic infections and to provide a reference for prevention. METHODS: Stool samples were treated by acid-ether centrifugation; iodine staining and direct-smearing were performed; intestinal parasites were examined under a microscope; characteristics of parasitic infections in population were analyzed using the descriptive epidemiological method. RESULTS: 10 kinds of parasites were detected; the infection rate of clonorchissinensis was the highest, followed by B. hominis, hookworm, whipworm and roundworm in order (x(2) = 131.188, 1261.928, 129.386, P < 0.01); The overall infection rates in 2013 and 2005 were 37.08% and 41.07% respectively, and the infection rate in 2013 was lower than that in 2005 (x(2) = 20.5003, P < 0.01); All the infection rates of clonorchissinensis, hookworm, whipworm and roundworm in 2013 were lower than those in 2005 (x(2) = 18.275, 45.449, 34.855, 12.435, P < 0.01); Both in 2005 and 2013, the male infection rate was higher than that in female (x(2) = 12.859, 24.924, P < 0.01); For male, the infection rate of clonorchissinensis was the highest, followed by B. hominis (x(2) = 313.621, 104.409, P < 0.01); for female, the infection rate of B. hominis was the highest, followed by clonorchissinensis (x(2) = 95.293, 43.357, P < 0.01). For male, the age group of 41~ had the highest infection rate of clonorchissinensis in 2005 (x(2) = 5.734, P < 0.05), and the age groups of 31~ and 41~ had the highest infection rate of clonorchissinensis in 2013 (x(2) = 8.908, P < 0.01); for female, both in 2005 and 2013, the age group of 21~, 31~, 41~ and 51~ had the highest infection rate of clonorchissinensis (x(2) = 6.508, 5.145, P < 0.05). There was no difference in male infection rate of B. hominis in 2005 (x(2) = 10.134, P > 0.05); in 2013, the age group of 0~ had the highest infection rate (x(2) = 3.825, P < 0.05); for women, it was the highest in the age groups of 11~, 21~ and 31~ in 2005 (x(2) = 10.459, P < 0.01), 0~ and 11~ in 2013 (x(2) = 53.669, P < 0.01). For Hookworm infection in male, the highest infection rate was found in the age group of 11~ 21~ and 61~ in 2005 (x(2) = 4.547, P < 0.05), 61~ and ≥ 71~ in 2013 (x(2) = 4.843, P < 0.05); for female, the highest infection rate was found in the age groups of 51~ and 61~ both in 2005 and 2013 (x(2) = 5.709, 5.958, P < 0.05). CONCLUSION: In Nanning city, although there was a decline in the infection rate of intestinal parasites of attenders compared with 8 years ago, the infection rate was still high and intestinal parasites were various; The infection rate of geohelminthes had been reduced to a low level; Clonorchissinensis and B. hominis were still the insect species with the highest infection rate.

[PCR-based genotype classification of Blastocystis hominis isolates from college students of Guangxi].

Fifty-three Blastocystis hominis isolates were separated from the fecal specimens of carriers in college students from Guangxi and cultivated in vitro, and the genetic DNA was extracted. All the isolates were genotyped by PCR using seven pairs of known sequence-tagged site (STS) primers. The results showed there were five subtypes in the 53 isolates. Subtype 3 was the most popular one (32.1%, 17/53), followed by subtype 7 (9.4%, 5/53). Subtypes 1 (7.6%, 4/53), 4 (7.6%, 4/53), and 6 (1.9%, 1/53) were detected, while subtypes 2 and 5 were not detected. The genotypes of the other 22 isolates were unknown which were negative to all the STS primers.

In vitro study on the feasibility of magnetic stent hyperthermia for the treatment of cardiovascular restenosis.

Thermal treatment or hyperthermia has received considerable attention in recent years due to its high efficiency, safety and relatively few side-effects. In this study, we investigated whether it was possible to utilize targeted thermal or instent thermal treatments for the treatment of restenosis following percutaneous transluminal coronary angioplasty (PTCA) through magnetic stent hyperthermia (MSH). A 316L stainless steel stent and rabbit vascular smooth muscle cells (VSMCs) were used in the present study, in which the inductive heating characteristics of the stent under alternative magnetic field (AMF) exposure, as well as the effect of MSH on the proliferation, apoptosis, cell cycle and proliferating cell nuclear antigen (PCNA) expression of the rabbit VSMCs, were evaluated. The results demonstrated that 316L stainless steel coronary stents possess ideal inductive heating characteristics under 300 kHz AMF exposure. The heating properties were shown to be affected by the field intensity of the AMF, as well as the orientation the stent axis. MSH had a significant effect on the proliferation and apoptosis of VSMCs, and the effect was temperature-dependent. While a mild temperature of 43°C demonstrated negligible effects on the growth of VSMCs, MSH treatment above 47°C effectively inhibited the VSMC proliferation and induced apoptosis. Furthermore, a 47°C treatment exhibited a significant and long-term inhibitory effect on VSMC migration. The results strongly suggested that MSH may be potentially applied in the clinic as an alternative approach for the prevention and treatment of restenosis.

[Investigation on the infection of Blastocystis hominis in populations in Bama Yao Autonomous County of Guangxi].

497 fecal specimens were collected from 5 randomly selected villages of Bama County in December 2011, and tested for Blastocystis hominis infection using improved centrifugal sedimentation with hydrochloric acid-ether. Data were analyzed by villages, gender, occupation, age groups and ethnic populations. The results showed that 215 people of 497 were positive, with a prevalence of 43.3% (215/497). Pandang village had the highest infection rate of 55.7% (68/122), significantly higher than the other villages (P<0.05). There was no significant difference in genders, occupations, age groups and ethnic populations (P>0.05).

[Genotype analysis and isoenzyme patterns of ten isolates of Blastocystis hominis from Guangxi].

OBJECTIVE: To analyze genotypes and lactate dehydrogenase (LDH) and esterase (EST) patterns in 10 isolates of Blastocystis hominis collected from Guangxi. METHODS: Ten B. hominis isolates (BhGX1-BhGX10) were obtained from the fecal specimens of patients and cultivated in vitro, and then the genomic DNA was extracted. The isolates were genotyped by PCR using seven pairs of known sequenced-tagged site (STS) primers. Isoenzyme patterns of LDH and EST were investigated by SDS-PAGE. RESULTS: Out of the 10 isolates, 8 were identified as genotype I and the genotypes of the other two (BhGX4 and BhGX7) were unknown which were negative to all the STS primers. Among the ten isolates, 10 LDH bands were found, more with Rm37, Rm49, Rm57, Rm68 and Rm92. 12 bands showed in EST patterns: Rm14, Rm18, Rm23, Rm27, Rm35, Rm41, Rm45, Rm50, Rm55, Rm68, Rm77 and Rm82. Difference existed with the LDH and EST patterns among the isolates. CONCLUSION: Genotype I is the major one in the 10 B. hominis isolates from Guangxi, and the isolates show different isoenzyme patterns for LDH and EST.

[Isoenzyme patterns of the isolates of Blastocystis hominis from Guangxi].

OBJECTIVE: To observe malate dehydrogenase and alkaline phosphatase patterns of ten isolates of Blastocystis hominis (Bh) from Guangxi. METHODS: Blastocystis hominis agents were isolated from the fecal specimens of patients and cultivated in vitro. The samples were prepared for polyacrylamide gel slab electrophoresis (PAGSE). Sodium malate and 1-Naphthyl phosphoric acid sodium were used as substrates. NBT and fast blue RR salt were used to stain MDH and ALP respectively. The isoenzyme bands were recorded with relative mobility (Rm). RESULTS: Among the 10 isolates, 7 MDH bands were found, more with Rm34, Rm47, Rm51, Rm55, and Rm59. All the isolates showed Rm34 and Rm51 bands. 5 bands showed ALP patterns: Rm22, Rm25, Rm28, Rm35, and Rm38. Difference existed with the MDH and ALP patterns among the isolates. CONCLUSION: MDH and ALP patterns may indicate a genetic difference among the isolates, which might play a role in its classification.

[Observation on polytene chromosomes of the ovarian nurse cell of anopheles minimus from Yuanjiang].

Anopheles minimus collected from Yuanjiang, Yunnan Province, were bred with standard methods in lab. The ovarian nurse cells of A.minimus were separated and stained, and the whole polytene chromosomes were photographed under light microscope and compared with A.minimus from Guangxi. 365 samples of ovarian nurse cells were observed. The chromosomes included one telocentric sex-chromosome X, two submetacentric autosomes II (autosome II right arm, 2R and autosome II left arm, 2L) and two metacentric autosomes III (autosome III right arm, 3R, and autosome III left arm, 3L). The X is the shortest chromosome and the 2R is the longest one. In comparison with the pattern of polytene chromosomes of A. minimus from Guangxi, difference at 12 positions has been found at the parts of arms in banding sequences.