Lanzhou Region Research Articles

Depressive symptoms are not associated with risks of rapid renal function decline or chronic kidney disease in middle-aged and elderly with normal kidney function: a longitudinal investigation

To explore the association between depressive symptoms and the risks of rapid decline in renal function and chronic kidney disease (CKD) in middle-aged and elderly with normal kidney function. The residents aged 40- 75 years with eGFR≥60 mL·min-1·1.73 m-2 without proteinuria in Lanzhou region, who participated in the "REACTION" study carried out in 2011, were selected and followed up in 2014. A total of 4961 individuals with complete and qualified data from the two surveys were included in the subsequent analysis. Based on PHQ-9 questionnaire scores, the baseline population was divided into two groups with and without depressive symptoms. Cox proportional hazard analysis was used to compare the incidences of rapid renal function decline and CKD between the two groups and study the association of depressive symptoms with the risk of these renal conditions. PHQ-9 questionnaire scores were not found to correlate with baseline SCr, ALB, UACR or eGFR levels among the participarts (P>0.05). After a mean follow-up time of 3.4±0.6 years, 33.9% of the participants with depressive symptoms at baseline experienced a rapid decline in renal function and 3.6% progressed to CKD. During the follow-up, the incidence of rapid decline in renal function and the risk of developing CKD were not found to correlate with depressive symptoms in these participants (P>0.05) regardless of the type of the depressive syndromes. Depressive symptoms are not associated with the risks of rapid renal function decline or progression to CKD in middle-aged and elderly with normal kidney function.

Measuring Study on Energy Saving Performance of the Trombe Wall in School Building

The thermal engineering and energy saving performance of the Trombe wall of a laboratory building in a middle school of Lanzhou region in northwest China were measured and investigated. The results show that during the normal using period in winter 10 years after the building was built, the daily convection heat supply of single group vents is 6.89 kW, the daily average thermal efficiency of the Trombe wall is 18.4 %. In addition, in the process of using the building, it needs to notice that the ventilated channel must be maintained clean and unhindered status, the vents devices must be repaired periodically in order to ensure good opening and closing function, and the vents should be avoided blocking and the ventilation heating mechanism of the Trombe wall should be avoided destroying in later renovation or decoration of the building.

Magnetostratigraphy and Palaeoclimatic Significance of the Late Pliocene Red Clay‐Quaternary Loess Sequence in the Lanzhou Basin, Western Chinese Loess Plateau

AbstractThe history of red clay‐loess accumulation in the Chinese Loess Plateau (CLP) is the key to understanding the aridification history of the Asian interior and the uplift of the Tibetan Plateau. Here we present high‐resolution magnetostratigraphy and grain‐size records of a 265.7‐m‐long drill core of the red clay‐loess sequence at Gaolanshan in the Lanzhou Basin from the western CLP. Our results, combined with the loess‐paleosol stratigraphy and regional stratigraphic correlation, indicate that the most complete and continuous red clay‐loess sequence since ~3 Ma was first found in the western CLP, which is ~0.8 Myr older than the previously investigated Quaternary loess in the Lanzhou region, and the age of the oldest Lanzhou loess‐paleosol sequence is ~2.8 Ma. Consequently, the major enhancement of the aridification at 2.8 Ma in the Asian interior was primarily controlled by the uplift of the Tibetan Plateau and global cooling.

Three kinds of ammonia oxidizing microorganisms play an important role in ammonia nitrogen self-purification in the Yellow River.

To develop the microbial resources of the Yellow River, seven water samples were collected along the Lanzhou region of the river from upstream to downstream for testing. Analysis of various physico-chemical indexes was conducted, and key parameters influencing the water quality were selected through principal component analysis, after which the decisive factors impacting water quality were determined by correlation and regression analysis. The results indicated that (1) DO, NH3-N, NO2--N, TN, TC, As, Cr6+ and Pb were the main physico-chemical factors influencing water quality in the Lanzhou region, with NH3-N having the greatest effect. (2) Ammonia-oxidizing microorganisms [ammonia-oxidizing archaea (AOA), ammonia-oxidizing bacteria (AOB), and anaerobic ammonia-oxidizing bacteria (AMX)] were found to mediate the transformation of NH3-N in the studied section. AOA was the primary microbe community among the two aerobic ammonia-oxidizing microorganisms (AOA and AOB) in the Yellow River. (3) Phylogenetic analysis showed that there were some known groups, and there were still many unknown species in the water of the studied section, especially within the AMX population. (4) Correlation analysis revealed that AOA has strong adaptability to unhealthy environments, and that some environmental factors (higher concentrations of carbon, nitrogen and some heavy metals) could increase the AOA gene abundance. Overall, these results suggested there are rich ammonia-oxidizing microbial resources, especially AOA, in the Lanzhou section of the Yellow River, which have the potential for application in nitrogen sewage treatment.

Prevalence and Characteristics of Quinolone Resistance in Salmonella Isolated from Retail Foods in Lanzhou, China

The aim of this study was to determinate the prevalence of Salmonella in retail foods and its resistance to quinolones in retail foods in Lanzhou, People's Republic of China. In this work, 2,182 food samples, collected from March 2015 to December 2018, were analyzed to detect Salmonella and then analyzed for serotype distribution, quinolone resistance, and quinolone-resistant gene detection. The findings demonstrate that the overall prevalence of Salmonella in these food categories was low. A total of 41 (1.9%) of 2,182 food samples were found to be positive for Salmonella. Ten distinct serovars were identified, and Salmonella Derby, Salmonella Anatum, and Salmonella Enteritidis were the most prevalent serovars. According to the broth microdilution test, the resistance percentages were 90.2% to nalidixic acid, 39.0% to enrofloxacin, 41.5% to ciprofloxacin, 29.3% to ofloxacin, and 26.8% to levofloxacin. Among the quinolone-resistant isolates, 12 strains had a single mutation in gyrA at codon 83 (Ser→Phe) or codon 87 (Asp→Asn or Asp→Gly). Five isolates had one parC mutation (Ser80→Arg) and one or two gyrA hot spot mutations. qnr genes were found in seven isolates (five qnrB and two qnrD), and the aac(6')-Ib gene in seven isolates. Two isolates carry both qnrB and aac(6')-Ib-cr genes. Based on these results, a low prevalence of Salmonella contamination in retail foods was found, but it might play a potential risk factor in the spread of quinolone-resistant Salmonella strains in the Lanzhou region.

Energy supply nutrients and mineral composition analysis in breast milk in Lanzhou urban

Objective To analyze the energy supply nutrients (protein, fat and lactose) and mineral elements (calcium, copper, iron, zinc, magnesium, sodium, potassium) supplied in breast milk from the resident of Lanzhou, and investigate the problems of those energy supply nutrients and mineral elements in breast milk of this population so that to provide basis for breast feeding. Methods Breast milk from 1 215 mothers whose babies were fed totally by the breast milk and grew well was collected and assayed for the contents of protein, fat, lactose, calcium, copper, iron, zinc, magnesium, sodium and potassium in Lanzhou region. The optimal range for breast feeding was set by normal distribution method. The results were compared with the breast milk from other internal region in order to clarify the contents difference. Results The prevalence of mother-milk-fed in this region was 48.5%. The normal ranges (unit: g/100 g) of fat, lactose and protein were 1.57-5.11, 6.58-7.16 and 0.79-1.35, and the normal ranges of calcium, copper, iron, zinc, magnesium, sodium and potassium were 5.25-7.83 mmol/L, 5.66-8.28 mmol/L, 0.14-0.3 mmol/L, 15-64.48 μmol/L, 0.98-1.62 mmol/L, 1.92-18.82 mmol/L, 7.95~17.31 mmol/L in the high quality breast milk. Compared with the other internal region, the normal ranges of the protein, fat and lactose in Lanzhou were lower. The contents of protein, fat, lactose, calories, calcium, copper, zinc and sodium in the breast milk from the whole investigated population were significantly lower compared with breast milk of high quality (P<0.01). Conclusion The quality of breast milk in Lanzhou is not so good. The contents of various nutrients in breast milk should be improved to a proper level by appropriate ways so that to improve the growth and development of the baby. Key words: Breast milk; Protein; Fat; Lactose; Constant trace element

Greater health risk in wet season than in dry season in the Yellow River of the Lanzhou region

The Yellow River flows through Lanzhou city and is the only drinking water source for 3.6 million residents. Yet, little is known regarding the safety and quality of the Yellow River for resident consumption. To address this knowledge-gap, water samples were collected from different sites within this section during the dry and wet seasons. Physico-chemical parameters and microbial community metrics were analyzed to assess the health risk associated with this Chinese mother river. Water quality of the river was better during the dry season (March–April) than in the wet season (September–October). Fifteen conventional physico-chemical and biological indices, such as NH3-N, NO2−-N, total nitrate (TN), five day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), volatile phenol (VP), and coliform abundances, generally exceeded acceptable standards. The average abundance of coliforms was 2.8 times that of acceptable standards in the dry season and 4.6 times the standards in the wet season. The concentration of the toxic metal As was more than two times than that of the national standard in waters from the wet season. Microbial community analysis also indicated that community diversity and species richness were positively correlated with the concentrations of several physico-chemical parameters. The results indicate that As and Cr6+ pose potential risk for human health through consumption by residents. Further, the results indicated that human activities are the main causes of water pollution, and that long-term strict monitoring should be conducted to ensure the safety of drinking water consumption and the health of the environment.

Numerical Analysis of Ground Motion Effects in the Loess Regions of Western China

Loess is widely distributed in the western part of China and its area comprises 6.6% of Chinese territory. Because of the characteristics of high porosity, low strength, and weak cementation, the loess is characterized by high seismic vulnerability which has been observed and confirmed by many researchers at home and abroad. The postquake field investigation and the laboratory study have shown that the ground motion effects, including the amplification effects and slope effects, were obvious in loess sites. Moreover, the causes of landslides, seismic subsidence, and liquefaction were mainly attributed to this special soil structure and properties. In this paper, based on the data of shear wave velocity of typical loess in Lanzhou region, combining the results of dynamic triaxial tests, the numerical analysis of ground motion effects in the loess regions is analyzed. The results reveal how the ground motion effects are checked and demonstrated the important role of numerical simulations while studying the characteristics of ground motions.

Magnetostratigraphic age and monsoonal evolution recorded by the thickest Quaternary loess deposit of the Lanzhou region, western Chinese Loess Plateau

The loess-paleosol sequences of the Chinese Loess Plateau (CLP) are major paleoclimatic archives which document the evolution of the East Asian Monsoon (EAM) and changes in the Northern Hemisphere ice sheets during the Quaternary glacial-interglacial cycles. However, the mechanisms regulating the trend of EAM variations on a tectonic scale are unclear. The loess deposits of the western CLP, which have a close relationship with tectonics and climate, are much better-suited to exploring these mechanisms than those of the central CLP. However, studies of long-term EAM evolution from the western CLP have been hindered by the lack of long, accurately-dated sequences with high sediment accumulation rates. Here, we address this problem via high resolution magnetostratigraphic, magnetic susceptibility and grain-size analyses of a 416.2 m-long drill core located at Xijin Village, near Lanzhou. Paleomagnetic dating indicates that the basal age of the Xijin loess is ∼2.2 Ma. The χ and grain-size records reveal that the East Asian Summer Monsoon (EASM) and East Asian Winter Monsoon (EAWM) strengthened synchronously at ∼1.24 Ma. Subsequently, during interglacial periods, the EASM began to penetrate, and then dominate, in the Lanzhou region. This was followed by two stepwise uptrends, commencing at ∼0.87 and ∼0.62 Ma, which resulted in an increasingly moist interglacial climate in the region. We suggest that the uplift of the Tibetan Plateau was largely responsible for these three stepwise enhancements of the EASM. Overall, however, the long-term trend of strengthening in EAWM in the area may have been primarily caused by long-term global cooling from the Late Pliocene onwards.

Spatial analysis of surface deformation distribution detected by persistent scatterer interferometry in Lanzhou Region, China

Persistent scatterer synthetic aperture radar interferometry (PS-InSAR) is a remote sensing method that can be used to detect surface deformation, which is an indicator of potential geohazards. By capturing such deformations over time, it is possible to obtain valuable information regarding geohazards such as landslides. This study focused on the use of PS-InSAR to investigate the distribution and causes of surface deformation in the Lanzhou region of Gansu Province in China. Between 2003 and 2010, 41 advanced synthetic aperture radar images were captured by the Envisat satellite and analyzed using PS-InSAR, and the correlation between the observed surface deformation and topographic, geologic, and anthropogenic factors was derived based on a geographic information system platform. It was found that the largest number and highest density of surface deformations occurred at elevations of 1486–1686 m. It was also established that slope ranges of 25°–30° and 35°–40° are threshold values at which surface deformation changes abruptly, and that slopes with north and northwest aspects are most prone to surface deformation. The lithologies most susceptible to surface deformation are clay, sandy soil, and loess. The normalized difference vegetation index indicated that surface deformation occurred most often in areas with sparse vegetation. Anthropogenic activities, e.g., construction and wastewater discharge, could be inferred as causal mechanisms of surface deformation. Comparison of the distributions of geohazards and surface deformation showed considerable consistency, which proves surface deformation can induce geohazards. These results could help governments improve urban planning and geohazard mitigation.

Loess Slope Instability Assessment Based on PS-InSAR Detected and Spatial Analysis in Lanzhou Region, China

Lanzhou is a mountainous city in which serious disasters have occurred due to several slope hazards. We used PS-InSAR technique to detect surface deformation: an indicator of potential hazards. In the period extending from 2003 to 2010, 41 Envisat ASAR images were captured and analyzed using PS-InSAR. We identified 27186 PS points. The deformation velocity in this area is found to being 3.5 mm/year ~ -5.4 mm/year. The results were inserted into a GIS to derive spatial interpolations and map zones with different magnitudes of surface displacement. Then, we used the analytical hierarchic process (AHP) to statistically assess the susceptibility of loess slope hazards with lithology, slope, altitude, distance to road, Ndvi, land use and aspect. According to the result of the model, the study area could be classified into three categories: stable, less unstable and unstable. Causal mechanisms include human interactions in the landscape (construction, waste water discharge, etc.) and slope instability processes (landslide, subsidence, etc.).

Application of Prestressed Anchor Composite Soil Nail Wall in Deep Foundation Pit Engineering at Lanzhou Region

The paper introduces the application of prestressed anchors and soil nails support system in complex soil layer deep foundation pit engineering at Lanzhou region based on the deep foundation pit engineering in Gansu Provincial Hospital of TCM as the background and discusses its key technology. The effect shows that scheme of the design of foundation pit support engineering is reasonable and effective.The engineering meets requirements of design and environment.The monitoring results show that prestressed anchors can control the horizontal displacement and the change rate of slope′s vertical settlement effectively. The experience of engineering is significance for similar engineerings at Lanzhou region.

Numerical Analysis on the Heat Transfer Characteristics of the Radiator in a Heating Room

Natural convective heat transfer is the most important means to supply heat load for resident building to keep necessary indoor air temperature in winter. To determine the surface convective heat transfer coefficient (CHTC) of a radiator is of primary importance to evaluate the heat flow within building interiors, and thereby to affect the thermal comfort and the overall energy consumption of a building. In this paper, a turbulent k-ε model is used to numerically analyze the heat transfer characteristics of a radiator used in a heating room in Lanzhou region of China. The results indicate that the averaged Nu number of radiator surface increases with increasing outer wall thermal conductivity, decreasing outdoor temperature and decreasing radiator surface area, respectively. And the outer wall thermal conductivity has weak influence on the local Nu number of radiator surface.

Ground Motion Prediction Equation for Lanzhou Region from Small Earthquake Records

By small earthquake records from the Gansu broadband digital earthquake network, five regional source and crustal medium parameters, stress drop Δσ, quality factor parameters Q0 and η, geometrical spreading parameters R1 and R2, are inversed for the Lanzhou area. Envelops of Fourier spectra are adopted as the objective function, the values of those parameters are 34.625bars, 95.665, 0.360, 58.188km and 105.650km, respectively. These values are adopted to calculate Fourier amplitude spectra, and complex spectra are formed by combining with random phase spectra. Acceleration time histories can be simulated, and PGAs on different moment magnitude-distance pairs are obtained previously. Compared with several observed strong ground motion data, the result is lower in the case of Mw=5.0, passes through the data in the case of Mw=6.0 and higher than the record of Mw=7.0. It is adopted in regional seismic zonation. Compared with The Zonation Map of Earthquake Ground Motion Parameters in China (GB18306-2001), the result is close to the map when PGA is lower than 0.2g.

The Analysis of Solar-Earth Source Heat Pump Combined Operating

This article describes the solar - earth source heat pump system characteristics and operating principles, the various operating modes of the system are discussed, and the system applied in Lanzhou region were analyzed. Pointed out that the relatively rich regions in the solar promote the use of solar - earth source heat pump technology has good prospects for development.

Application of Solar Thermal Utilization in New Rural Construction in Lanzhou Region

Solar energy is clean and reproducible energy,it has an important advantage when we use solar energy in heating,supplying hot water and drying in residential buildings.Practical experience confirms that appropriate design of these systems can achieve good results to use solar energy if they compared with conventional system.This paper aims to investigate the good use for solar energy in new rural construction of Lanzhou, we integrate traditional passive solar house, solar heating, solar drying into a new classified system ,design the versatile system for lowtemperature radiant floor heating,supplying hot water and crops drying.Meanwhile, control method and handling precautions are improved.Through further analysis on economic efficiency comparison with solar floor heating and conventional heat source with new rural residential integrated energy price method,analysis on energy-saving and environmental benefit.At last we come to the conclusion the system is worth popularizing in new rural construction.

Late early Oligocene East Asian summer monsoon in the NE Tibetan Plateau: Evidence from a palynological record from the Lanzhou Basin, China

The latest Early Oligocene record from the Lanzhou Basin, northeast Tibetan Plateau, presents an opportunity to investigate early stage of the Asian monsoon patterns due to its special location. The record provides insights into the global zonal climate and the development of the non-zonal monsoon system. The study identifies possible links between factors governing the monsoonal patters and paleoaltimetry of the Tibetan Plateau. Sporomorphs results indicate the dominance of arboreal plants (both coniferous and broad-leaved) corresponding to a wetter environment, while xerophytes were rare. Based on the Coexistence Approach (CA), the climate of the Lanzhou Basin is likely to have been similar to that of present-day sites in Southeast China, i.e., characterized by relatively high precipitation and a warm climate. Both qualitative analysis of the sporomorph assemblages and quantitative calculations indicate that monsoons similar to those of the present daywere formed in East Asia and reached the Lanzhou region in inner Asia. High percentages of Picea, generally associated with the relatively high topography of the NE Tibetan Plateau, correlate well with the high paleoaltimetry of the main Tibetan Plateau during the Oligocene. Thus, the East Asian monsoon during this time can be closely linked to an uplifted Tibetan Plateau, following modeled relationships between the Tibetan Plateau and monsoon patterns. However, we believe such high precipitation may have mainly resulted from the orographic barrier, rather than being driven by zonal climate factors. Further investigation into the extent of, and controls on, the region of high precipitation should help clarify the role of these processes.

Detection and clinical characteristics analysis of human bocavirus 1-3 in children for acute respiratory infection in Lanzhou area

To study the clinical and molecular epidemiology characteristics of human Bocavirus 1-3 (HBoV1-3) in children for acute respiratory infection in Lanzhou area. Nasopharyngeal aspiration samples and throat swabs were collected from 524 children with ARTI at the First Hospital of Lanzhou University, Gansu Province, China, between December 2009 and November 2010. Nested PCR was employed to screening HBoV1-3, which amplified a 518-bp fragment of the partial NS1 gene. Furthermore, a standard reverse transcription-PCR was used to screen for other common respiratory viruses. The overall frequency of HBoV was 8.2% (43/524), lining up behind human rhinovirus, RSV, parainfluenza virus 3. Thirty of the HBoV-postive children(69.8%) were co-infected with other respiratory viruses. The prevalence of HBoV1 in ALRTI was obviously higher than that in AURI. The 2 HBoV2 NS1 sequences shared 99% and 100% nucleotide sequence identity with HBoV2 strain CU47TH respectively. Two cases of HBoV2 postive children appears gastrointestinal symptoms. The one HBoV3 NS1 sequences shared 99% nucleotide sequence identity with HBoV3 isolate 46-BJ07. The HBoV3 was detected at the first time in lanzhou area. HBoV1-3 infection exists in children with acute respiratory tract infections in Lanzhou region, HBoV1 were dominant. The mixed infection rate was higher.

Assessment of the genotoxicity in toad Bufo raddei exposed to petrochemical contaminants in Lanzhou Region, China

Single cell gel electrophoresis or comet assay, micronucleus (MN) test and global DNA methylation detection were used to assess the genotoxicity in toad Bufo raddei exposed to the petrochemical (mainly oil and phenol) polluted area in Lanzhou Region (LZR) comparing with a relatively unpolluted area in Liujiaxia Region (LJXR). The results from the present study indicated that DNA damage and MN frequency in toad from LZR were significantly higher than those from LJXR at the same sampling month, whereas the degree of global DNA methylation was lower, which implies that the petrochemical contaminants at environmental level in LZR were genotoxic to B. raddei. The degree of genotoxic damage was obviously related with the extent of pollution among the three sampling months in LZR. The significantly positive correlations between DNA damage and concentrations of oil and/or phenol existed in liver cells but erythrocytes, implying that liver is more suitable as a sentinel tissue for the assessment of genotoxic impact of low-level contamination. The results from both comet assay and global DNA methylation detection on liver cells showed that the genotoxicity varied significantly with oil and/or phenol concentrations, suggesting that these two methods are relatively sensitive and suitable for monitoring the genotoxicity of petrochemical pollutants on amphibians.

Contaminants-Induced Oxidative Damage on the Carp Cyprinus carpio Collected from the Upper Yellow River, China

The Yellow River, the second largest river in China, is the most important resource of water supply in North China. In the last 40 years, even in the upper Yellow River, with the development of industry and agriculture, more and more contaminants have been discharged into this river and greatly polluted the water. Although a routine chemical component analysis has been performed, little is known about the real toxic effects of the polluted water on organisms at environmental level. To explore whether the pollutants induced oxidative stress and damage to aquatic organisms, malondialdehyde (MDA) level and activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione S-transferase (GST) in hepatopancreas, kidney and intestine of the field-collected carp Cyprinus carpio from a mixed polluted (Lanzhou Region, LZR) and a relatively unpolluted (Liujiaxia Region, LJXR) sites of the upper Yellow River were measured. The results showed that when the values of LZR compared with those of LJXR, SOD and GST activities increased and GPx activity decreased significantly in all the three organs (P < 0.05-0.01); CAT activity decreased but MDA level increased significantly (P < 0.05-0.01) only in kidney and intestine. In conclusion, the results of this study suggest that the pollutants can induce obvious oxidative damage in the carp, and the SOD, GST and GPx might be better indicators for the oxidative damage in aquatic organisms.