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The study on rare metals in coal and coal-bearing strata is a hot point issue in the field of coal geology. Rare metals that could be highly-enriched in coal and coal-bearing strata and thus can be industrially utilized include Li, Sc, Ti, V, Ga, Ge, Se, Zr, Nb, Hf, Ta, U, rare earth elements (lanthanides and Y), and noble metals. In this paper, the geological origin, modes of occurrence, and evaluation methods for coal-hosted rare metal deposits including Ge, Ga, U, Nb, rare earth element ore deposits are reviewed. The study on coal-hosted rare metal ore deposits can not only provide important evidence of coal geochemistry and coal mineralogy for coal formation origin, coal-seam correlation, coal basin formation and epigenetic deformation, regional geology-evolution, and sudden geological event, but also are practically significant for the development of coal circular economy, environmental protection during coal utilization, and for the security of national rare metal resources. [ABSTRACT FROM AUTHOR]

To investigate the effects of intercropped rape and film mulching on soil water content in dryland apple orchards during the low-water consumption period on the Loess Plateau, soil water content and soil water storage were measured with in situ field observations. The results showed that at the sprout period of apple trees, mean water content in 0-200 cm soil layer under apple trees with film mulching + intercropping 50% width rape (PR 1 ) and apple trees with film mulching + intercropping 100% width rape (PR 2 ) treatments increased by 7.9% and 6.9% compared with the control (apple trees without film mulching+row clearing), respectively. At the blossom period of apple trees, mean soil water content under these two treatments increased by 3.5% and 6.9%, respectively. At the sprout period of apple trees, soil water competition between apple trees and rape occurred in both PR 1 and PR 2 treatments, with the competition being most severe at the boundaries. At the sprout period, competition in the PR 1 treatment was less intense than that in the PR 2 treatment. At the blossom period, competition in the PR 1 treatment was not obvious, but the competition in the PR 2 treatment was significant. Moreover, at the sprout and blossom period, a low-soil-water-content zone was observed in the PR 2 treatment. Compared with the control, both PR 1 and PR 2 treatments increased soil water storage in 0-80 cm layer, and soil water was not deficit in the 0-200 cm layer. In conclusion, the implementation of PR 1 model is conducive to improve soil water availability in the dryland apple orchard on the Loess Plateau during the low-water consumption period.

Water scarcity is a critical factor influencing rain-fed agricultural production on the Loess Plateau, and the exploitation of rainwater is an effective avenue to alleviate water scarcity in this area. This study was conducted to investigate the spatial and temporal distribution of soil moisture in the 0-300 cm under a 21-year-old apple orchard with the rainwater collection and infiltration (RWCI) system by using a time domain reflectometer (TDR) probe on the Loess Plateau. The results showed that there was a low soil moisture zone in the 40-80 cm under the CK, and the RWCI system significantly increased soil moisture in this depth interval. Over this depth, the annual average soil moisture under RWCI 40 , RWCI 60 and RWCI 80 was 39.2%, 47.2% and 29.1% higher than that of bare slope (BS) and 75.3%, 85.4% and 62.7% higher than that of CK, respectively. The maximum infiltration depth of water under RWCI 40 , RWCI 60 and RWCI 80 was 80 cm, 120 cm and 180 cm, respectively, and the soil moisture in the 0-60, 0-100 and 0-120 cm was more affected by RWCI 40 , RWCI 60 and RWCI 80 , respectively. Over the whole growth period of apple tree, the maximum value of soil moisture content in the 0-300 cm existed in the RWCI 80 treatment, followed by the RWCI 40 and RWCI 60 treatments. Overall, the RWCI system is an effective meaning of transforming rainwater to available water resources and realizing efficient use of agricultural water on the Loess Plateau.

In this paper, an Nd∶YAG laser with 10ns pulse width and output wavelength of 1 064 nm was employed to ablate Gd metal target and Gd-doped glass target for plasma generation. The out-of-band (OOB) radiation of extreme ultraviolet sources with the two target configurations was comparatively studied. It has been found that the continuous radiation emitted by the plasma is the main component of the out-of-band radiation. The spectral distribution of the continuum emission matches that of blackbody radiation with a temperature of about 5 eV. And it is also found that the intensity of OOB radiation can be considerably decreased by using Gd-doped glass target. Optical Emission Spectroscopy (OES) has been used to analyze the temporal and spatial behaviors of electron temperature (Te) and density (Ne) of the Gd-doped glass target plasma, and experimental results show that temporal evolution of electron temperature and density of the plasma are found to be decayed exponentially with the increasing of delay time. At 125 ns after laser irradiation, electron temperature and density were 4 eV and 1.2×1018 cm-3 respectively, and then decreased to 1.5 eV and 8×1017 cm-3 with delaying time of 250 ns. On the other hand, spatial evolution of electron temperature and density show that both of them first increase and then decrease in the region of 1~10 mm from the target surface. The electron temperature and electron density achieves the maximum of 2.6 eV and 8.5×1017 cm-3, respectively, when the probe location away from the target surface 6 mm.

A detailed investigation was conducted to study the variations of manganese contents and fractions in soil under different land use patterns in Sanjiang Plain, Northeast China. The purpose of this work was to study the changes of manganese and its fractions during wetland cultivation and their relationships with environment factors. The results indicated that the total manganese contents (Mn(tot)) were relatively low in wetland soils. When wetland was cultivated into dry farmland (corn field), M(tot) showed an increasing trend, and when wetland was cultivated into rice paddy, Mn(tot) manifested a decreasing trend. Among the four fractions of manganese in soil, the residual part (Mn(res)) and the reducible part (Mn(red)) were predominant while the acid extractable part (Mn(ext)) and the oxidizable part (Mn(oxi)) were secondary. During the cultivation of wetlands to corn field or rice paddy, Mn(oxi) was the only part with significant change. Mn(tot) and the transformations among manganese fractions were affected by many environmental factors, with sulfur content, pH and dissolved organic carbon playing leading roles.

Mn content and its profile distribution characteristics were investigated in soils from the typical Deyeuxia angustifolia wetland, corn filed, paddy field, poplar forest and island forest in Sanjiang Plain. Results indicated that Mn content was relatively low and was in the range of 107.73-2 798.99 mg/kg with the average value of 403.24 mg/kg. Mn content significantly differed by land use (F = 9.272, P < 0.001) and was in the order of island forest > poplar forest > corn field > Deyeuxia angustifolia wetland > paddy field. On the whole, Mn content in each soil layer was in the order of corn filed > Deyeuxia angustifolia wetland > rice paddy in field and was in the order of island forest > poplar forest in the vertical direction. It suggested that Mn was enriched after wetlands were reclaimed in to the upland filed and Mn concentration was decreased when wetlands were changed into rice paddy. Correlation analysis showed that Mn content in soil significantly negatively related to pH (r = -0.279, P < 0.05), significantly positively related to sulfur (r = 0.383, P < 0.01) and dissolved organic carbon (r = 0.244, P < 0.05), and weakly related to soil organic matter and available sulfur, respectively. Changes of environmental factors had impacts on Mn species and then resulted in soil Mn content.

Nutrient elements and salinity in soil covered by different vegetations including Phragmites australis (Clay.) Trin., Typha orientalis Presl., Puccinellia distans Parl, and Suaeda salsa in Shuangtaizi estuarine wetlands were investigated to study their distribution characteristics and to reveal the nutrient element variation during the vegetation succession processes. Results indicated that total potassium, total phosphorus and salinity were different significantly in soil between different plant communities while available phosphorus, total nitrogen, available nitrogen, available potassium, total sulfur, iron and soil organic carbon were different insignificantly. Correlation analysis suggested that soil organic carbon were related significantly to total nitrogen, available phosphorus, available potassium, which implied that decomposition of plant litter might be the mail source of soil nitrogen and available nutrient. Salinity was significantly related to total phosphorus and iron in soil. In Shuangtaizi estuarine wetland soil, ratios of carbon to nitrogen (R(C/N)) was in the range of 12.21-26.33 and the average value was 18.21, which was higher than 12.0. It indicated that soil organic carbon in Shuangtaizi estuarine mainly came from land but not ocean and plants contributed the most of soil organic matters. There was no significant difference in R(C/N) between soil from the four plant communities (F = 1.890, p = 0.151). R(C/N) was related significantly to sol salinity (r = 0.346 3, p = 0.035 8) and was increasing with soil salinity.

Objective: To investigate the effect of electroacupuncture (EA) of "Sanyinjiao" (SP 6) on the uterus in dysmenorrhea rats so as to study its underlying analgesic mechanism., Methods: A total of 48 SD rats during diestrus were randomized into normal saline (control) group, model group and acupuncture group according to a random number table, with 16 rats in each group. Dysmenorrhea model was established by subcutaneous injection of Estradiol benzoate (0.5 mg/d on the 1st and 10th day, and 0.2 mg/d from day 2 to day 9, once daily for 10 days) and oxytocin (2 U/rat, once on day 10). Malondialdehyde (MDA) and beta-endorphin (beta-EP) contents in the uterus were detected by radioimmunoassay, and the heat shock protein 70 (HSP 70) immunoactivity of the uterus was detected by immunohistochemistry., Results: In comparison with the control group, MDA content in the uterus was increased significantly in the model group (P < 0.01), while the beta-EP level and the immunoactivity of HSP 70 immune-reaction (IR) positive products in the uterus decrease significantly (P < 0.01) and moderately, respectively in the model group. In comparison with the model group, uterine MDA content in the EA group was decreased significantly (P < 0.01), while uterine beta-EP level increased considerably (P < 0.01) and HSP 70 expression was upregulated to a certain degree., Conclusion: EA of "Sanyinjiao" (SP 6) can reduce MDA content and upregulate beta-EP level of the uterus in rats with dysmenorrhea, which may contribute to its analgesic effect in relieving dysmenorrhea by clearing away oxygen free radicals and raising analgesic substance in the uterus.

Objective: To observe and compare the analgesic effect of electroacupuncture (EA) at "Sanyinjiso" (SP 6), "Hegu" (LI 4) and "Xuehai" (SP 10) in dysmenorrhea rats so as to investigate the functional specificity of acupoint., Methods: One hundred SD female rats aged three-month-old in the diestrus examined by the vaginal smear screening were randomly divided into a saline group, a model group, a Sanyinjiao (SF 6) group, a Hegu (LI 4) group and a Xuehai (SF 10) group, 20 rats in each group. The rats in the last four groups were given Estradiol Benzoate combined with Oxytocin to prepare the models of dysmenorrhea and in the saline group were given the same dose of saline. Last three groups were treated with electroacupuncture (EA) at Sanyinjiao" (SF 6), "Hegu" (LI 4) and 'Xuehai" (SF 10) respectively. The writhing behaviors of the rats in each group were observed within 20 min performing electroacupuncture from the start of the pain and the waveforms of uterine contraction were recorded., Results: In terms of the writhing behaviors, the writhing latency in the Hegu (LI 4) group was extended significantly (P < 0.05, P < 0.01) and the writhing numbers in the Hegu (LI 4) group were decreased significantly (both P < 0.05) as compared with those in the Sanyinjiao (SF 6) group and in the Xuehai (SF 10) group. In terms of the waveforms of uterine contraction, compared with that in the model group, the amplitude and the activity of uterine contraction in both Sanyinjiao (SF 6) group and Hegu (LI 4) group were decreased significantly (all P < 0.05), and with no significant difference between the Xuehai (SF 10) and the model group (P > 0.05)., Conclusion: For comprehensive assessment of the analgesic effect of electroacupuncture at different acupoints by using the writhing behaviors and the waveforms of uterine contraction, "Hegu" (LI 4) is the best, "Sanyinjiao" (SP 6) is the next and "Xuehai" (SP 10) is the third. showing a relatively functional specificity of the acupoint.

Objective: To investigate the effect of preventive moxibustion at the acupoint of 'Guanyuan" (CV 4) on the stress-related hormones, proteins and genes in natural menopausal rats, and explore its protective mechanism., Methods: One hundred and twenty eight healthy female SD rats were used in this study, in which 16 rats aged 4 months were used as normal control group, the rest 10-month-old rats with disorder of estrus cycle were randomly divided into 7 groups, including 4 control groups at the age of 10, 12, 14 and 16 months, and 3 preventive moxibustion groups at the age of 12, 14 and 16 months, 16 cases in each group. The 10-month-old rats were treated with preventive moxibustion at the acupoint of "Guanyuan" (CV 4), twice a week for 8 weeks consistently, then observed on the following 12, 14 and 16 months. Its effects on the level of heat shock protein 70 (HSP 70), heat shock protein 70 mRNA (HSP 70 mRNA), corticotropin-releasing hormone (CRH), beta-endorphin (beta-EP), adrenocorticotrophic hormone (ACTH) in the different nuclei of hypothalamus were examined with radio-immunity, immunohistochemistry or in situ hybridization methods., Results: In the control groups, the expression of HSP 70 and HSP 70 mRNA was increased in paraventricular, arcuate and supraoptic nucleus, the level of CRH, beta-EP was showed with declining trend in volatility, while the content of ACTH was increased. In comparison to the same-aged control groups, the preventive moxibustion groups were showed that the expression of HSP 70 in the 14-month-old group was lower and the expression of HSP 70 mRNA in the 12 and 16-month-old group was significantly higher in the paraventricular nucleus (all P < 0.05), the expression of HSP 70 in the 12 and 14-month-old groups and HSP 70 mRNA in the 12-month-old group was significantly increased in the arcuate nucleus (P < 0.05, P < 0.01), while the expression of HSP 70 in the 14-month-old group and HSP 70 mRNA in the 12 and 16-month-old group was significantly decreased in the supraoptic nucleus (all P < 0.05), the content of CRH and ACTH decreased significantly in 14-month group (P < 0.05, P < 0.01), but the content of beta-EP obviously went up in the 12-month-old group (P < 0.05)., Conclusion: Preventive moxibustion at the acupoint of "Guanyuan" (CV 4) can regulate the expression of stress proteins, genes and hormones in the hypothalamus for the natural menopausal rats, which might be playing a protective role.

Objective: To observe the influence of preventive acupuncture (PA) and preventive moxibustion (PM) at "Guanyuan" (CV 4) on the immune function in natural climacteric rats., Methods: A total of 160 female SD rats were randomized into control, PA and PM groups, the former one group was further divided into 10 month (mon), 12 mon, 14 mon and 16 mon subgroups, and the later two groups were further divided into 12 mon, 14 mon and 16 mon subgroups, with 16 rats in each. In addition, other 16 female SD rats aged 3.5 mon were used as the young control (YC) group. "Guanyuan" (CV 4) was punctured with an acupuncture needle and the needle was retained for 20 min, or given with one ignited moxa-cone from the age of 10 mon on. The treatment was conducted twice every week, 8 weeks altogether. The expression of HSP 70 and HSP 70 mRNA of the spleen tissue was detected by using immunohistochemistry and in situ hybridization respectively, and serum IL-2 and TNF-alpha contents were assayed by using radio-immunoassay., Results: In comparison with YC group, 1) the expression of spleen HSP 70 and HSP 70 mRNA increased significantly in 10 mon control (mon-C), 12 mon-PM and 12 mon-PA groups, and 14 mon-PA group (only HSP 70 mRNA) (P < 0.05, P < 0.01); 2) HSP 70 expression decreased remarkably in 14 mon-C, 16 mon-C and 16 mon-PA groups (P < 0.05, P < 0.01); 3) IL-2 contents decreased evidently in 12 mon-C and 14 mon-C groups, and TNF-alpha contents increased obviously in 12 mon-PM, 12 mon-PA and 16 mon-C groups (P < 0.05). In comparison with the corresponding same age control groups, HSP 70 and HSP 70 mRNA expression increased significantly in 12 mon-PM and 12 mon-PA groups, 14 mon-PM and 16 mon-PM (HSP 70 only), 14 mon-PA (HSP 70 mRNA only) groups (P < 0.05, P < 0.01); IL-2 level of 12 mon-PM group, and TNF-alpha contents of 12 mon-PM and 12 mon-PA groups increased markedly (P < 0.05, P < 0.01). No significant differences were found between PM and PA groups in most different age groups (P > 0.05)., Conclusion: Both preventive acupuncture and preventive moxibustion can upregulate the expression of spleen HSP 70 and HSP 70 mRNA and serum IL-2 and TNF-alpha levels, which may contribute to their effects in enhancing the immune function in menopausal rats.

Objective: To describe the clinical manifestations and lung imaging characteristics of the human transmissible highly pathogenic H5N1 avian influenza., Methods: The clinical manifestations and lung imaging characteristics of human transmissible highly pathogenic H5N1 avian influenza in one patient were reviewed and analyzed., Results: The patient had the clear history of occupational exposure. The fever and symptoms of influenza were prominent at onset and associated with the symptoms of the digestive tract. The laboratory findings comprised the significant decrease of the white blood cell count and the lymphocyte number and the impairment of the liver function and the myocardial enzymes. The disease progressed rapidly and multiple organs including lung, heart, liver and kidneys were involved. It was ineffective to administer anti-fungal, anti-virus and anti-inflammation medicines. It was in vain to use mechanical ventilation and pneumothorax intubation and closed drainage as well as the support therapy. In the X-ray film, the lesions progressed quickly and changed diversely with absorption and development at the same time. The nasal and throat swabs and the gargle specimen were detected with RT-PCR and real time PCR by Chinese Center for Disease Control and Prevention. The results showed that both the specific HA and NA genes of the avian influenza virus H5N1 subtype were positive and in the same time a strain of avian influenza virus A/jiangxi/1/2005H5N1) was separated and obtained from the nasal and throat swabs. The autopsy showed that diffuse injury of alveolus in lungs, DIC and multiple organ injury., Conclusion: The human transmissible highly pathogenic H5N1 avian influenza is a lethal disease. The disease progresses rapidly with the absorption and development at the same time in the lungs and unfortunately there are no effective therapeutic measures. The prevention of the contagious disease for the occupationally exposed population should be emphasized.