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Groundwater serves as an important water source for residents in and around mining areas. To achieve scientific planning and efficient utilization of water resources in mining areas, it is essential to figure out the chemical formation process and the ground water sulfur cycle that transpire after the coal mining activities. Based on studies of hydrochemistry and D,18O-H2O,34S-SO4 isotopes, this study applied principal component analysis, ion ratio and other methods in its attempts to reveal the hydrogeochemical action and sulfur cycle in the subsidence area of Pingyu mining area. The study discovered that, in the studied area, precipitation provides the major supply of groundwater and the main water chemistry effects are dominated by oxidation dissolution of sulfide minerals as well as the dissolution of carbonate and silicate rocks. The sulfate in groundwater primarily originates from oxidation and dissolution of sulfide minerals in coal-bearing strata and human activities. The mixed sulfate formed by the oxidation of sulfide minerals and by human activities continuously recharges the groundwater, promoting the dissolution of carbonate rock and silicate rock in the process. [ABSTRACT FROM AUTHOR]

Continuous cropping of the same crop leads to soil degradation and a decline in crop production, and these impacts could be mitigated through rotation cropping. Although crop rotation enhances soil fertility, microbial community diversity, and potato yield, its effects on the soil ecosystem multifunctionality (EMF) remain unclear. In the present research, we comparatively examined the effects of potato continuous cropping (PP) and rotation cropping [potato–oat rotation (PO) and potato–forage maize rotation (PFM)] on the soil EMF as well as the roles of keystone taxa, microbes abundance, and chemical properties in EMF improvement. It was demonstrated that soil EMF is increased in rotation cropping (PO and PFM) than PP. Soil pH was higher in rotation cropping (PO and PFM) than in PP, while total phosphorus (TP) and available phosphorus (AP) were significantly decreased than that in PP. Rotation cropping (PO and PFM) markedly changed the bacterial and fungal community compositions, and improved the potential plant-beneficial fungi, e.g., Schizothecium and Chaetomium, while reducing the abundances of the potentially phytopathogenic fungi, e.g., Alternaria, Fusarium, Verticillium dahiae, Gibberella, Plectosphaerella, Colletotrichum, Phoma, and Lectera in comparison with PP. Also, co-occurrence patterns for bacteria and fungi were impacted by crop rotation, and keystone taxa, e.g., Nitrospira.1, Lysinibacillus, Microlunatus.1, Sphingomonas.3, Bryobacter.1, Micromonospora, and Schizothecium, were enriched in PO and PFM than PP. The structural equation model (SEM) further demonstrated that cropping systems increased soil ecosystem multifunctionality through regulating SOM and keystone taxa (Schizothecium1), and keystone taxa were mediated by soil pH. This study suggested that rotation cropping might contribute to the improvement of soil ecosystem multifunctionality as well as the development of disease-suppressive soils in comparison with potato continuous cropping. [ABSTRACT FROM AUTHOR]

A pot experiment was performed under rain-shelter conditions to explore the effects of drought stress and post-drought rewatering on the abundance of an ammonia-oxidizing bacteria (AOB) strain in corn (Zea mays L.) rhizosphere soils and the relationship between the AOB strain and corn (Zea mays L.) compensatory growth after drought stress rewatering. Corn seedlings were used as test materials, and one AOB strain was isolated and screened from the soil. The experimental design included six treatments: (1) wet (WT), (2) wet with AOB strain inoculation during wetness (WI), (3) wet with AOB strain inoculation during rewatering (WR), (4) post-drought rewatering (DT), (5) post-drought rewatering with AOB strain inoculation during wetness (DI), and (6) post-drought rewatering with AOB strain inoculation during rewatering (DR). Wetness and drought stress were obtained by keeping the soil water content at 75-80% and 50-55% of the field capacities, respectively. The results showed that the isolated and screened AOB strain (S2_8_1) had 100% similarity to Ensifer sesbaniae. The inoculation of S2_8_1 during the wet period in the DI treatment caused it to colonize the rhizosphere soil. Drought stress decreased its abundance, but rewatering resulted in a great increase. The S2_8_1 in the DI treatment increased the total biomass, water use efficiencies, net photosynthetic rates, rhizosphere soil nitrification rates, leaf cytokinin concentrations, xylem sap cytokinin concentrations, copy number of S2_8_1 in rhizosphere soils, and organic carbon contents in rhizosphere soils by 23, 104, 35, 30, 18, 29, 104, and 23% on day 10 after rewatering compared with WT treatment. In the DI treatment, the increase in rhizosphere soil nitrification rates caused by S2_8_1 during wetness was closely related to the cytokinin delivery from roots to leaves and increased leaf cytokinin concentrations. The increase in leaf cytokinin concentrations improved rewatering corn growth, which caused compensatory growth and increased water use. Compensatory and over-compensatory growths occurred in DT and DR treatments, respectively. Therefore, the coexistence of the strain of AOB with corn in rhizosphere soil increased the corn compensatory growth by regulating soil nitrification and root-induced leaf cytokinin. [ABSTRACT FROM AUTHOR]

Abstract  Genetic diversity and population genetic structure of autotetraploid and diploid populations of rice collected from Chengdu Institute of Biology, Chinese Academy of Sciences, were studied based on 36 microsatellite loci. Among 50 varieties, a moderate to high level of genetic diversity was observed at the population level, with the number of alleles per locus (A e) ranging from 2 to 6 (mean 3.028) and polymorphism information content ranging from 0.04 to 0.76 (mean 0.366). The expected heterozygosity (H e) varied from 0.04 to 0.76 (mean 0.370) and Shannon’s index (I) from 0.098 to 1.613 (mean 0.649). The autotetraploid populations showed slightly higher levels of A e, H e, and I than the diploid populations. Rare alleles were observed at most of the simple sequence repeat loci in one or more of the 50 accessions, and a core fingerprint database of the autotetraploid and diploid rice was constructed. The F-statistics showed genetic variability mainly among autotetraploid populations rather than diploid populations (F st = 0.066). Cluster analysis of the 50 accessions showed four major groups. Group I contained all of the autotetraploid and diploid indica maintainer lines and an autotetraploid and its original diploid indica male sterile lines. Group II contained only the original IR accessions. Group III was more diverse than either Group II or Group IV, comprising both autotetraploid and diploid indica restoring lines. Group IV included a japonica cluster of the autotetraploid and diploid rices. Furthermore, genetic differences at the single-locus and two-locus levels, as well as components due to allelic and gametic differentiation, were revealed between autotetraploid and diploid varieties. This analysis indicated that the gene pools of diploid and autotetraploid rice were somewhat dissimilar, as variation exists that distinguishes autotetraploid from diploid rices. Using this variation, we can breed new autotetraploid varieties with some important agricultural characters that were not found in the original diploid rice varieties. [ABSTRACT FROM AUTHOR]

Many computer systems, such as those for open system environments or multimedia services, need an efficient schedulability test for online admission control of new jobs. Although various polynomial time schedulability tests have been proposed, they often fail to decide the schedulability of the system precisely when the system is heavily loaded. On the other hand, most precise schedulability tests proposed to date have a high complexity and may not be suitable for online tests. In this paper, we present new efficient online schedulability tests for both the periodic process model and the multiframe process model in uniprocessor environments. The schedulability tests are shown to be more precise and efficient than any existing polynomial-time schedulability tests. Moreover, the tests can be done incrementally as each new task arrives at the system. Our proposed tests can also be used for the multiframe model where a task may have different computation times in different periods. We show the performance of the proposed schedulability tests in several simulation experiments. [ABSTRACT FROM AUTHOR]

The generalized transmission line model (GTLM) analysis has been applied to the study of cylindrical-circular microstrip antennas. In this study, the equivalent circuit for the circular microstrip antenna excited at TM11 mode is given, and formulation of the input impedance is derived. Numerical results of the input impedance for different feed positions and cylinder radii are calculated and presented, and the accuracy of the GTLM analysis is discussed. [ABSTRACT FROM AUTHOR]

An analysis using a generalized transmission-line model (GTLM) for a probe-fed cylindrical-rectangular microstrip antenna is presented, The equivalent circuit elements for the microstrip antenna modeled as a transmission line loaded with wall admittances ate derived, and the expression for the input impedance is given. Numerical results of the input impedance ate calculated and presented as a function of the cylinder radius and the substrate thickness. Excellent agreement of the GTLM solutions with the experimental results is observed. [ABSTRACT FROM AUTHOR]

Effective arguments have been made for the importance of expanded attention to understanding how family preferences influence decisions to choose long-term care. The effects of preference on the utilization of long-term care deserve further research, especially on a longitudinal basis. The family members of 582 first-time stroke patients from the neurology departments of tour teaching hospitals in Taiwan were categorized into two groups based on their attitudes toward type of long-term care, i.e., a preference for nursing home care (n1 324) or a preference for home care (n2 258). The consistency rate between preference and utilization of the type of long-term care was estimated by the division of number of families preferring one type of long-term care by the number of families actually utilizing the services preferred. Results indicated that the consistency rate for those with nursing home preference was 8.3% while the consistency rate for those with home care preference was 94.2%. Accessibility of nursing home facilities near family residences was significantly associated with whether those preferring nursing home services actually utilized them, and the odds ratio was 20.8. The family manpower available lot caregiving at home was tremendously associated with whether families utilized home care when home care was preferred; the odds ratio was 33.3. The preference for the type of long-term care was a strong predictor of the utilization when home care was preferred, yet not when a nursing home was preferred. The low consistency between preference and utilization for nursing homes preferred is due to the low accessibility of nursing home facilities in Taiwan. How to provide sufficient support to families for caregiving at home, and how to deal with the barrier of accessibility to nursing home services should be two major concerns for those who are planning and operating the long-term care system and for those trying to design institutional services and noninstitutional services as alternatives. [ABSTRACT FROM AUTHOR]