Two relaxation peaks were found in the complex susceptibility of ferrofluids. Both can be described by the Vogel-Fulcher law t t 0 f͑T͒ exp͓E͞k͑T 2 T 0 ͔͒. Nevertheless, the physical origins for these two relaxations are quite different. We found that Néel relaxation strongly depends on the dipoledipole interaction. The dramatic dependence can be described by a surprisingly simple scaling relation: t t 0 exp͓E͞k͑T 2 af 0.8 ͔͒, where f is the volume fraction of the dipoles. In contrast, Brownian relaxation is much less sensitive to the concentration of magnetic moments because the interparticle force is mainly hydrodynamic in nature. [S0031-9007(96)00634-5] PACS numbers: 75.50. Mm, 61.20.Lc, 75.40.Gb, 82.70.Dd 0031-9007͞96͞77(2)͞390(4)$10.00

An apparent increase in the frequency of human adenovirus type 4 (HAdV-4) infections among general populations has been observed over the past 10 years. However, available epidemiological data that may reflect previous viral circulation and assist in predicting potential outbreaks are sparse, particularly in mainland China and Africa. In this study, a convenient neutralization assay for use in the surveillance of historical HAdV-4 infections was established based on a recombinant luciferase-expressing virus. Subsequently, the neutralizing antibodies (nAbs) of 1013 healthy adult serum samples from China and Sierra Leone were evaluated. Our results showed that over 50% of the participants from China and nearly 70% of donors from Sierra Leone had detectable nAbs against HAdV-4 despite the few infection cases officially reported in these regions. Furthermore, the prevalence of nAbs to HAdV-4 is lower than that to HAdV-5, and both varied by geographic location. In addition, the seropositive rates of both HAdV-4 and HAdV-5 nAbs increased with age. However, the nAbs stimulated by HAdV-4 remained stable at low (≤200) levels among the different age groups, whereas moderate (201–1000) or high (>1000) nAb levels were produced by HAdV-5 and tended to decrease with age. These results elucidate the human humoral immune response against HAdV-4 and revealed that this virus may be an underestimated causative agent of respiratory disease among adults in China and West Africa, demonstrating the importance of HAdV-4 surveillance and providing useful insights for the future development of HAdV-4-based vaccines.

The tree-ring chronologies of Abies georgei Orr were developed for 3 sites at different elevations: the southern (2750 m), middle (3050 m), and northern (3400 m) parts of the Baimang Snow Mountains in northwestern Yunnan Province, China. The climate-growth response analysis indicated that trees at different elevations respond differently to environmental changes. The radial growth of trees found at the middle and high elevation sites was determined by temperature variables (mean, maximum, and minimum temperatures), particularly during the summer season (June to August), while moisture availability (precipitation and relative humidity) during spring (in March) was the crucial climate factor for tree growth at the low elevation site. The linear climate-growth model derived from the composite chronology of the 2 high elevation sites was verified with independent data from 1958 to 2005, and accounted for 33.4% of the mean temperature variation during summer (June to August). Based on this model, summer minimum temperature variations were reconstructed for the past 296 yr. The reconstruction revealed that cool climates mainly occurred in 1732-1743, 1758-1780, 1791-1824, 1836-1847, 1853-1862, 1908-1929, 1964-1976, and 1979-1993, while warm climates prevailed in 1718-1731, 1744-1756, 1781-1790, 1825-1835, 1883-1907, 1930-1963, and 1995 to present. Spectral analysis of the reconstruction using the multi-taper method (MTM) indicated the existence of some multidecadal (about 70 yr) and bidecadal (about 20 yr) cycles, which might correspond to the related cycles of solar activity, and significant peaks at about 2 to 8 yr, in agreement with the spectral mode of El Niño Southern Oscillation (ENSO)-type variability. KEY WORDS: Summer temperature · Climate reconstruction · Tree-ring · Northwestern YunnanResale or republication not permitted without written consent of the publisher Clim Res 47: 207-218, 2011 Tree-ring measurements provide a particularly valuable indicator of climatic history as they offer precise dating, extensive spatial availability, and climatologically high sensitivity (Fritts 1976, Schweingruber 1996. Tree-ring data play an important role in reconstructing the climate variability of the Northern Hemisphere and have been integrated worldwide into research on global change (Esper et al. 2002, Mann et al. 2008. The coniferous forests in northwestern Yunnan are ancient and diverse (Wu 1987), offering a compelling opportunity to explore tree-ring data, but few dendroclimatological studies have been conducted in this region. The earliest such study in this region was carried out at Haba Snow Mountains, in which Wu et al. (1988) reported a tree-ring chronology indicative of air temperature during the last 400 yr and suggested the existence of similar variations in the Tibetan Plateau. Based on the tree-ring data of the central Hengduan Mountains, variability in summer temperatures and spring droughts during the past several centuries have also been reconstructed (Fan et al. 2008, 2009a, Li et al. 2...

Water yield is an important ecosystem service, which is directly related to human welfare and affects the sustainable development. Using the integrated valuation of environmental services and tradeoffs model (InVEST model), we simulated the dynamic change of water yield in Qinghai lake watershed, Qinghai, China, and verified the simulation results. This paper emphatically explored how precipitation change and land use/land cover change (LUCC) affected the change of water yield on the spatial and temporal scales. Before 2004, the areas of cultivated land and unused land showed a dramatic increasing tendency, while forestland and water area presented a decreasing trend. After 2004 cultivated land changed slowly, unused land decreased. Grassland revealed a general trend of decline during 1977-2018, while built-up land basically presented a linear increase. The results show that water yield fluctuated and increased during 1977 . From 1977 to 2000, the mean water yield in each sub-watershed showed an increasing trend and afterward a decreasing one. After 2000, the sub-watersheds basically showed an increasing tendency. There was a strong correlation, with a correlation coefficient of 0.954 ** (** correlation is significant at the 0.01 level), between precipitation and water yield. Land use/land cover change can change the hydrological state of infiltration, evapotranspiration, and water retention. Meanwhile, the correlation between built-up land and water yield was the highest, with a correlation coefficient of 0.932, followed by forestland, with a correlation coefficient of 0.897. Through the analysis of different scenarios, we found that compared with land use/land cover change, precipitation played a more dominant role in affecting water yield.Water 2020, 12, 11 2 of 18 accuracy of the model output and the validation and evaluation of the performance of models in different circumstances and locations [11,12]. The input parameters have a great influence on the output results of the model. Many studies use sensitivity analysis methods to analyze the dependence between model output and variables [13,14], and in turn adjust model input parameters to find a set of optimal parameters. In fact, the input parameters of water yield module need to be calculated by physical equation or empirical equation [15,16]. So, we should make the input parameters more reasonable and accurate by standardizing the input data and taking full account of the regional characteristics and differences. In addition, the output results of the model are compared and verified through the observation data to evaluate the performance of the model without sensitive analysis methods and parameter adjustment, so as to provide a supporting evidence for us to use the model in the similar areas without measured data or insufficient data.Since the 1970s, many distributed hydrological models, including soil and water assessment tool (SWAT) [17], artificial intelligence for ecosystem services (ARIES) [18], integrated valuation of ecosystem services and trade...

foliar-level stoichiometry plays an important role in ecosystem elemental cycling. Shifts in foliar ratios of carbon to nitrogen (c:n) and nitrogen to phosphorus (n:p) in response to global change can therefore have a large impact upon ecosystem function. We conducted a meta-analysis with 2,236 paired observations from 123 published studies to investigate the responses of foliar C:N and N:P ratios to experimental global change treatments, i.e. warming, increased precipitation, drought, n addition and elevated carbon dioxide concentration (eco 2), in field conditions. Foliar C:N and N:P ratios were neither affected by warming nor by increased precipitation. Foliar C:N ratio increased with drought and eco 2 , and decreased with n addition. foliar n:p ratios declined with eco 2 , and increased under drought and n addition. our results suggested the responses of the c:n ratio to global change were mainly related to shifts in foliar [n], whereas changes in the n:p ratio were related to the responses of both [n] and [p]. Moreover, the response magnitude of foliar n:p ratio decreased with treatment duration under increased precipitation, n addition and eco 2. Our findings are important for our understanding of plant nutrient dynamic and modeling of nutrient biogeochemistry under global change.

This study's aim is provide an overview of the patients who suffered spinal cord injury (SCI) after the magnitude 8.0 Wenchuan earthquake, including each patient's demographic and epidemiological characteristics, bladder management status, and quality of life (QOL). We also assessed the relationships between bladder management methods, symptomatic urinary tract infection (SUTI), and QOL. Two years after the 2008 Wenchuan earthquake, a cross‐sectional face‐to‐face survey was conducted on 180 patients with SCI. A self‐administered questionnaire and the WHOQOL‐BREF assessment were used to assess injury‐related information, bladder management methods, and SUTI. Statistical analysis was performed using the Chi‐square test and analysis of variance. A p value <0.05 was considered statistically significant. This study found that a male‐to‐female ratio of approximately 1.2:1, including 98 (54.4%) male patients and 82 (45.6%) female patients. Thoracic‐level injuries were seen in 82 patients (45.56%), 60 (33.33%) patients had lumbar‐level injuries, 18 (8.33%) patients had thoracolumbar‐level injuries, and a small number of patients had cervical‐ or sacral‐level injuries. Sixty‐two patients (34.44%) demonstrated normal voiding, 65 (36.11%) required manually assisted voiding, 29 (16.11%) required catheterization, and 24 (13.33%) used aurine‐collecting apparatus. The prevalence of SUTI was 43.89%. Patients who emptied their bladder via manually assisted voiding, catheterization, or with the use of a urine‐collecting apparatus demonstrated higher rates of SUTI compared with patients who voided normally (p < 0.05); the patients who required catheterization had higher rates of SUTI compared with patients who required manually assisted voiding (p < 0.05). When manually assisted voiding and catheterization were compared with the use a urine‐collecting apparatus, no statistically significant differences were observed in terms of the risk of developing SUTI. The patients in this study demonstrated low scores on the WHOQOL‐BREF physical domain (11.61 ± 3.80), psychological domain (10.11 ± 3.63), social domain (11.46 ± 2.84), and environmental domain (11.86 ± 2.51). The patients who reported normal voiding also demonstrated the best QOL in terms of physical, psychological, and social component scores (p < 0.05). In conclusion, the percentage of women in this study is higher than that reported in other studies on traumatic causes of SCI. Patients who suffered SCI following the Wenchuan earthquake demonstrate poor bladder management status and are unable to take advantage of urodynamic testing that is used to monitor the functional state of the bladder. This study's findings indicate that bladder management methods influence the rate of SUTI and the QOL of patients with SCI. Caring for SCI patients following a disaster requires comprehensive long‐term planning. Bladder management of patients with SCI is essential for improving the QOL of these patients.

Transarterial chemoembolization (TACE) is a promising treatment for patients suffering from unresectable liver malignancy. A coarse emulsion of doxorubicin solution and iodized oil is widely used in clinical practice. However, this coarse emulsion lacks sufficient physical stability and can split into water and oil very quickly. Furthermore, most chemotherapeutics are quickly released into systematic circulation, causing serious adverse effects. In this study, we aimed to prepare reversed lipid-based nanoparticles (RLBNs) dispersed in iodized oil as nanocarriers for the delivery of hydrophilic chemotherapeutics. Unlike a simple mixture of drug solution and oil, RLBN is a homogenous system and possesses a hydrophobic nanostructure that has high dispersibility in oils. Hydrophilic chemotherapeutics were entrapped in the polar core juxtaposed by highly biocompatible lipid materials, such as egg phospholipids. A sustained drug-release profile was observed in both in vitro and in vivo pharmacokinetics studies. The results of computed tomography showed that RLBN–doxorubicin–iodized oil could remain in the tumor region for more than 14 days and that the growth of tumors was effectively suppressed. Thus, the current results suggest that RLBN is a promising drug delivery system and is compatible with TACE treatment.

The reliability of high-power light-emitting-diode (LED) devices strongly depends on the die-attach quality because voids may increase junction temperature and total thermal resistance of LED devices. Die-attach material has a key role in the thermal management of high-power LED package by providing low-contact thermal resistance. Thermal and mechanical analyses were carried out by experiments and thermal simulation. The quantitative analysis results show that thermal resistance of die-attach layer (thermal resistance caused by die-attach material and voids in die-attach layer) plays an important role in total thermal resistance of high-power LED packaging according to the differential structure function of thermal transient characteristics. The increase of void fraction in die-attach layer causes the increases of thermal resistance of die-attach layer; the thermal resistance increased by 1.95 K/W when the void fraction increased to 62.45%. The voids also make an obvious influence on thermal stress and thermal strain of chip; the biggest thermal stress of chip was as high as 847.1 MPa compared to the 565.2 MPa when the void fraction increases from being void-free to 30% in the die-attach layer.