New Mexico State University Carlsbad

Simulations of Asian dust emissions over the past 43 years are presented based on a size‐dependent soil dust emission and transport model (NARCM) along with supporting data from a network of surface stations. The deserts in Mongolia and in western and northern China (mainly the Taklimakan and Badain Juran, respectively) contribute ∼70% of the total dust emissions; non‐Chinese sources account for ∼40% of this. Several areas, especially the Onqin Daga sandy land, Horqin sandy land, and Mu Us Desert, have increased in dust emissions over the past 20 years, but efforts to reduce desertification in these areas may have little effect on Asian dust emission amount because these are not key sources. The model simulations indicate that meteorology and climate have had a greater influence on the Asian dust emissions and associated Asian dust storm occurrences than desertification.

Trends in Chinese global radiation, direct horizontal radiation, diffuse radiation, clearness index, diffuse fraction and percentage of possible sunshine duration for the period 1961–2000 were evaluated based on data for daily surface solar radiation and monthly sunshine duration. Annual means for all six variables were calculated for each station and for China as a whole. Linear regression analysis was used to characterize long‐term annual trends in these variables. Over the latter half of the 20th century, there have been significant decreases in global radiation (−4.5 W/m 2 per decade), direct radiation (−6.6 W/m 2 per decade), clearness index (−1.1% per decade), and the percentage of possible sunshine duration (−1.28% per decade), but diffuse fraction has increased (1.73% per decade). Although there is some evidence that conditions have improved in the last decade, the consistent spatial and temporal variations of these variables support the theory that increased aerosol loadings were at least partially responsible for the observed decreases in global radiation and direct radiation, the clearness index, and the monthly percentage of possible sunshine duration over much of China.

Studies were conducted as part of Asian Pacific Regional Aerosol Characterization Experiment (ACE‐Asia) to characterize the major ion and elemental composition of aerosol particle samples collected at Gosan, an ACE‐Asia supersite (GOS, Korea, total suspended particle or TSP samples) and at Zhenbeitai (ZBT, China, TSP and particles < 2.5 μm diameter or PM 2.5 samples), a site closer to the sources for Asia dust. The concentrations of 24 elements in the ZBT PM 2.5 samples were correlated with Al (an indicator of mineral dust), and the ratios of these elements to Al were similar to those in a loess certified reference material, but a second group of elements was enriched over crustal proportions most likely as a result of pollution emissions. The concentrations of various water‐soluble (WS) cations (Na + , K + , Ca 2+ , Mg 2+ ) also were generally well correlated with Al in both the ZBT and GOS samples, with the exception being WS K + at ZBT, where biomass burning may have had an effect. The percentage of calcium that was soluble approached 100% at ZBT versus ∼60% at GOS, and the ratio WS Ca 2+ /Al also was higher at ZBT. The molar ratio of sulfate to WS Ca 2+ was ∼0.1 at ZBT but increased to near unity at GOS, where the aerosol nitrate/WS Ca 2+ ratio was tenfold to hundredfold higher compared with ZBT, presumably because of anthropogenic influences. The observed differences in aerosol characteristics between sites can only be explained as the end product of different source contributions combined with complex processes involving gas‐particle conversion, size‐dependent fractionation, and aerosol mixing.

Total suspended particulate (TSP) and particulate matter less than 2.5 microm in aerodynamic diameter (PM2.5) samples were collected over Xi'an for a 1-yr period to characterize the seasonal variations of water-soluble inorganic ions and to evaluate the effectiveness of the pollution policies and controls during the past 10 yr. Mass concentrations of five cations (sodium [Na+], potassium [K+], ammonium [NH4+], calcium [Ca2+], and magnesium [Mg2+]) and four anions (fluoride [F-], chloride [Cl-], nitrate [NO3-], and sulfate [SO4(2-)]) were determined by ion chromatography. The yearly arithmetic-mean mass concentrations of the total measured water-soluble ions in TSP and PM2.5 were 83.9 +/- 58.4 and 45 +/- 34.3 microg x m(-3). The most abundant ions in TSP were SO4(2-), NO3-, Ca2+, and NH4+; whereas in PM2.5 the dominant ions were SO4(2-), NH4 +, and NO3-. Most of the ions were more concentrated in the PM2.5 than in TSP, but two exceptions were Ca2+ and Mg2+. Comparisons of the molar ratios of Mg2+/Ca2+ in TSP indicated that fugitive dust was the main source for these two ions, and the influence of soil dust from outside of the city was most evident during dust storms. The mass concentrations of SO4(2-), NO3-, , NH4+, and K+ in TSP were highest in winter and lowest in spring, but Ca2+ was much higher in spring than other seasons because of suspended mineral dust. In PM2.5, NO3- and K+ also showed winter maxima, but SO4(2-) and NH4+ were highest in summer. Calculations of ion equivalents showed that TSP samples were more alkaline than PM2.5, the latter being weakly acidic in winter and autumn. High sulfur and nitrogen oxidation ratios occurred in summer and autumn, and there was evidence for the formation of ammonium bisulfate in TSP, ammonium sulfate in PM2.5, and ammonium nitrate in both fractions. Comparisons with the results of prior studies indicate that pollution controls in Xi'an have reduced the levels of air pollution over the past 10 yr. The SO4(2-) concentration during the heating season in 2006 was only about one-eighth of that in 1996, and NH4+ decreased to one-ninth of that in 1996. Seasonal variations in the NO3-/SO4(2-) ratio are different than the patterns observed 10 yr ago, suggesting that emission sources have changed, with those from motor vehicles becoming increasingly important.

As a part of the Atmosphere/Ocean Chemistry Experiment (AEROCE), daily aerosol samples were collected in the marine boundary layer at Barbados, West Indies (13.17°N, 59.43°W), Bermuda (32.27°N, 64.87°W), and Mace Head, Ireland (53.32°N, 9.85°W), and in the free troposphere at Izaña, Tenerife, Canary Islands (28.30°N, 16.48°W; 2360 m asl). In this report, we use multiple variable regression analyses with methanesulfonate (MSA) and Sb and/or NO 3 − as the independent variables to assess the relative contributions of the marine biogenic and anthropogenic sources to the total non‐sea‐salt (nss) SO 4 2− concentrations at the AEROCE sites. On the basis of 2 years of data at Bermuda and Barbados, the marine nss SO 4 2− /MSA mass ratios (19.6 ± 2.1 and 18.8 ± 2.2) were consistent throughout the year and comparable to those at American Samoa in the tropical South Pacific (18.1 ± 0.9). At Mace Head (based on 1 year of data), this ratio was about 3.01 (±0.53). An analysis of the residuals and an assessment of the root mean square deviations indicate that the ratio at Mace Head can also be reasonably applied throughout the year. However, there is enough uncertainty during the winter that we cannot rule out a significant increase (to about 20) during periods with low concentrations of both MSA and NO 3 − . The results from 4 years indicate that the marine contribution is too low to permit a reasonable assessment of the biogenic nss SO 4 2− /MSA ratio at Izaña. The continental nss SO 4 2− /Sb mass ratio varies significantly from one location to another. At Bermuda, where North American sources are expected to dominate, the ratio is about 29,000, about a factor of 2 higher than the average of 13,500 at Mace Head where European sources dominate. Intermediate values occurred at Barbados (18,000) and Izaña (24,000) where both European and North African sources are significant. Estimates based on these ratios indicate that, on an annual basis, the contributions from anthropogenic sources account for about 50% of the total nss SO 4 2− in aerosols at Barbados, 70% at Bermuda, 85–90% at Mace Head, and about 90% at Izaña. If the same biogenic nss SO 4 2− /MSA ratios are applicable to rainwater, then the relative contributions in precipitation at Barbados and Bermuda are comparable to those in aerosols.

In spring 2005, daily particulate matter (PM 2.5 ) aerosol samples were collected at Tongliao, a site in the Horqin sand land of northeastern China. The concentrations of 20 elements, 9 water‐soluble ions, and elemental and organic carbon (EC and OC, respectively) were determined in the filter samples. Crustal material was the major contributor to the PM 2.5 mass, but rural biomass burning and local urban pollution also influenced the composition of the aerosol. The mean PM 2.5 mass concentration was 126 ± 71 μ g m −3 (arithmetic mean ± standard deviation), with higher loadings during five dust storms (DS, 255 ± 80 μ g m −3 ) than for normal days (ND, 104 ± 43 μ g m −3 ) or pollution episodes (PE, 118 ± 52 μ g m −3 ). During the DS, crustal material accounted for 69% of the PM 2.5 mass, followed by carbonaceous matter (14%), sulfate (4%), nitrate (2%), ammonium (1%), and chloride (1%). The observed Si/Al, Ca/Al, and Fe/Al ratios during the DS events were different from those in dust from western or central/northern Asia. On normal days the percentage of crustal material decreased to 43%, and the mass of carbonaceous matter increased 2 times over that during DS. During the pollution episodes the contributions of sulfate and nitrate were 3 times those on DS while ammonium increased four‐fold. Secondary aerosols (NH 4 + , SO 4 2− , and NO 3 − ) were the dominant species during the pollution episodes, but SO 4 2− and NO 3 − also were important components of the aerosol during DS events, suggesting that mineral dust was mixed with other materials. Ion balance calculations indicate that the DS samples were alkaline, the ND samples were weakly alkaline, and the PE samples were slightly acidic. A deficit of measured anions during DS implied the presence of carbonate; this evidently accounts for ∼5.5% of the PM 2.5 mass. The average OC and EC concentrations were 16.3 ± 7.3 μ g m −3 and 3.4 ± 1.7 μ g m −3 , respectively. Noncrustal K was correlated with OC and EC, indicating that biomass burning was a major contributor to the regional carbonaceous aerosol.

Abstract. The spatial distribution of the aerosols over 86 Chinese cities was reconstructed from air pollution index (API) records for summer 2000 to winter 2006. PM10 (particulate matter ≤10 μm) mass concentrations were calculated for days when PM10 was the principal pollutant, these accounted for 91.6% of the total 150 428 recorded days. The 83 cities in mid-eastern China (100° E to 130° E) were separated into three latitudinal zones using natural landscape features as boundaries. Areas with high PM10 level in northern China (127 to 192 μg m−3) included Urumchi, Lanzhou-Xining, Weinan-Xi'an, Taiyuan-Datong-Yangquan-Changzhi, Pingdingshan-Kaifeng, Beijing-Tianjin-Shijiazhuang, Jinan, and Shenyang-Anshan-Fushun; in the middle zone, high PM10 (119–147 μg m−3) occurred at Chongqing-Chengdu-Luzhou, Changsha-Wuhan, and Nanjing-Hangzhou; in the southern zone, only four cities (Qujing, Guiyang, Guangzhou and Shaoguan) showed PM10 concentration >80 μg m−3. The median PM10 concentration decreased from 108 μg m−3 for the northern cities to 95 μg m−3 and 55 μg m−3 for the middle and southern zones, respectively. PM10 concentration and the APIs both exhibited wintertime maxima, summertime minima, and the second highest values in spring. PM10showed evidence for a decreasing trend for the northern cities while in the other zones urban PM10 levels fluctuated, but showed no obvious change over time. The spatial distribution of PM10 was compared with the emissions, and the relationship between the surface PM10 concentration and the aerosol optical depth (AOD) was also discussed.

During the Asian Pacific Regional Aerosol Characterization Experiment (ACE‐Asia) intensive field campaign conducted in the spring of 2001, aerosol properties were measured on board the R/V Ronald H. Brown to study the effects of the Asian aerosol on atmospheric chemistry and climate in downwind regions. Aerosol properties measured in the marine boundary layer included chemical composition; number size distribution; and light scattering, hemispheric backscattering, and absorption coefficients. In addition, optical depth and vertical profiles of aerosol 180° backscatter were measured. Aerosol within the ACE‐Asia study region was found to be a complex mixture resulting from marine, pollution, volcanic, and dust sources. Presented here as a function of air mass source region are the mass fractions of the dominant aerosol chemical components, the fraction of the scattering measured at the surface due to each component, mass scattering efficiencies of the individual components, aerosol scattering and absorption coefficients, single scattering albedo, Ångström exponents, optical depth, and vertical profiles of aerosol extinction. All results, except aerosol optical depth and the vertical profiles of aerosol extinction, are reported at a relative humidity of 55 ± 5%. An overdetermined data set was collected so that measured and calculated aerosol properties could be compared, internal consistency in the data set could be assessed, and sources of uncertainty could be identified. By adjusting the measured size distribution to take into account nonsphericity of the dust aerosol, calculated and measured aerosol mass and scattering coefficients agreed within overall experimental uncertainties. Differences between measured and calculated aerosol absorption coefficients were not within reasonable uncertainty limits, however, and may indicate the inability of Mie theory and the assumption of internally mixed homogeneous spheres to predict absorption by the ACE‐Asia aerosol. Mass scattering efficiencies of non‐sea‐salt sulfate aerosol, sea salt, submicron particulate organic matter, and dust found for the ACE‐Asia aerosol are comparable to values estimated for ACE 1, Aerosols99, and the Indian Ocean Experiment (INDOEX). Unique to the ACE‐Asia aerosol were the large mass fractions of dust, the dominance of dust in controlling the aerosol optical properties, and the interaction of dust with soot aerosol.

Physical activity plays an important role in children's cardiovascular health, musculoskeletal health, mental and behavioral health, and physical, social, and cognitive development. Despite the importance in children's lives, pediatricians are unfamiliar with assessment and guidance regarding physical activity in children. With the release of the 2018 Physical Activity Guidelines by the US Department of Health and Human Services, pediatricians play a critical role in encouraging physical activity in children through assessing physical activity and physical literacy; providing guidance toward meeting recommendations by children and their families; advocating for opportunities for physical activity for all children in schools, communities, and hospitals; setting an example and remaining physically active personally; advocating for the use of assessment tools and insurance coverage of physical activity and physical literacy screening; and incorporating physical activity assessment and prescription in medical school curricula.

The mass-particle size distributions (MSDs) of 9 elements in ground-based aerosol samples from dust storm (DS) and non-dust storm (N-DS) periods were determined for 12 sites in 9 major desert regions in northern China. The masses of the 9 elements (Al, Fe, K, Mg, Mn, Sc, Si, Sr and Ti) in the atmosphere were dominated by local mineral dust that averaged 270 mg m−3, and the MSDs for the elements were approximately log-normal. On the basis of Al data, the < 10 mm particles account for ˜84% of the total dust mass over the deserts. Model-calculated (‘‘100-step’’ method) dry deposition velocities (Vd) for the 9 dust-derived elements during N-DS periods ranged from 4.4 to 6.8 cm s−1, with a median value of 5.6 cm s−1. On the basis of a statistical relationship between D99% (the dust particle diameter corresponding to the uppermost 1% of the cumulative mass distribution) and Vd, one can also predict dry velocities, especially when D99% ranges from 30 to 70 mm. This provides a simple way to reconstruct Vd for dust deposits ( like aeolian loess sediments in the Loess Plateau). The estimated daily dry deposition fluxes were higher during DS vs. N-DS periods, but in most cases, the monthly averaged fluxes were mainly attributable to N-DS dust. Two regions with high dust loading and fluxes are identified: the ‘‘Western High-Dust Desert’’ and the ‘‘Northern High-Dust Desert,’’ with Taklimakan Desert and Badain Juran Desert as their respective centers. These are energetic regions in which desert-air is actively exchanged, and these apparently are the major source areas for Asian dust.

We present measurements of trace gases and fine aerosols obtained from a rural site in eastern China during 18 February to 30 April 2001. The field program aimed to characterize the variations in aerosol and gaseous pollutant concentrations and the emission signatures from the inland region of eastern China in the spring season. The data included O 3 , CO, NO, NO y *, SO 2 , methane, C 2 ‐C 8 nonmethane hydrocarbons (NMHCs), C 1 ‐C 2 halocarbons, and the chemical composition of PM2.5. The average hourly mixing ratios (±standard deviation) of CO, SO 2 , and NO y * were 677 (±315) ppbv, 15.9 (±14.6) ppbv, and 13.8 (±7.2) ppbv, respectively. The mean daytime ozone mixing ratio was 41 (±19) ppbv. The most abundant NMHC was ethane (3189 ± 717 pptv), followed by ethyne (2475 ± 1395 pptv), ethene (1679 ± 1455 pptv), and toluene (1529 ± 1608 pptv). Methyl chloride was the most abundant halocarbon (1108 ± 653 pptv). The average concentrations of particulate organic matter (POM, as organic carbon, OC, times 1.4) and elemental carbon (EC) in PM2.5 were 21.5 (±7) μg/m 3 and 2.5 (±0.7) μg/m 3 , respectively, and sulfate and nitrate levels were 17.3 (±6.6) and 6.5 (±4) μg/m 3 , respectively. CO showed moderate to good correlation with NO y * ( r 2 = 0.59), OC ( r 2 = 0.65), CH 3 Cl ( r 2 = 0.59), soluble potassium ( r 2 = 0.53), and many NMHCs, indicating contributions from the burning of biofuel/biomass. CO also correlated with an industrial tracer, C 2 Cl 4 , indicative of some influence from industrial sources. SO 2 , on the other hand, correlated well with EC ( r 2 = 0.56), reflecting the contribution from the burning of coal. Ammonium was sufficiently abundant to fully neutralize sulfate and nitrate, indicating that there were strong emissions of ammonia from agricultural activities. Silicon and calcium had poor correlations with iron and aluminum, revealing the presence of source(s) for Si and Ca other than from soil. Examination of C 2 H 2 /CO, C 3 H 8 /C 2 H 6 , nitrate/(nitrate + NO y *), and sulfate/(SO 2 + sulfate) suggested that relatively fresh air masses had been sampled at the study site in the spring season. Comparison of the observed ratios/slopes with those derived from emission inventories showed that while the observed SO 2 /NO y * ratio (1.29 ppbv/ppbv) in March was comparable (within 20%) to the inventory‐derived ratio for the study region, the measured CO/NO y * slope (37 ppbv/ppbv) was about 200% larger. The observed slope of CO relative to NMHC (including ethane, propane, butanes, ethene, and ethyne) also indicated the presence of excess CO, compared to the ratios from the inventories. These results strongly suggest that emissions of CO in eastern China have been underrepresented. The findings of this study highlight the importance of characterizing trace gases and aerosols within source regions of the Asian continent. The springtime results were also compared with data previously collected at the site in 1999–2000 and with those obtained on the Transport and Chemical Evolution over the Pacific (TRACE‐P) aircraft and from a coastal site in South China for the same study period.

Increasing anthropogenic emissions from Asia, especially from regions undergoing rapid industrial development, have raised interest in the outflow of chemically and radiatively important gases and aerosols. Previous studies have shown that high concentrations of Asian pollution spread over a broad region of the North Pacific every spring. Here we report on studies of aerosol concentrations at Midway Island (28°13′N, 177°22′W) in the central North Pacific over the period 1981–2000. Using a relatively simple procedure we estimate the natural and anthropogenic fractions of sulfate and nitrate aerosol and show that the estimated anthropogenic component almost doubled from 1981 to the mid‐1990s. This increase closely parallels estimates of increased emissions of SO 2 from China. However, measurements in the late 1990s suggest that sulfate and nitrate concentrations have stabilized and perhaps decreased. Thus over the longer term pollution emissions from Asia and concentrations over the North Pacific may be less than earlier projections, a factor which has implications for the assessment of future climate trends.

Daily mass concentrations of water-soluble inorganic (WS-i) ions, organic carbon (OC), and elemental carbon (EC) were determined for fine particulate matter (PM1, particles < 1.0 μm in diameter) collected at Xi'an, China. The annual mean PM1 mass concentration was 127.3 ± 62.1 μg m–3: WS-i ions accounted for ∼38% of the PM1 mass; carbonaceous aerosol was ∼30%; and an unidentified fraction, probably mostly mineral dust, was ∼32%. WS-i ions and carbonaceous aerosol were the dominant species in winter and autumn, whereas the unidentified fraction had stronger influences in spring and summer. Ion balance calculations indicate that PM1 was more acidic than PM2.5 from the same site. PM1 mass, sulfate and nitrate concentrations followed the order winter > spring > autumn > summer, but OC and EC levels were higher in autumn than spring. Annual mean OC and EC concentrations were 21.0 ± 12.0 μg m−3 and 5.1 ± 2.7 μg m–3 with high OC/EC ratios, presumably reflecting emissions from coal combustion and biomass burning. Secondary organic carbon, estimated from the minimum OC/EC ratios, comprised 28.9% of the OC. Positive matrix factorization (PMF) analysis indicates that secondary aerosol and combustion emissions were the major sources for PM1.

Redistribution of soil, nutrients, and contaminants is often driven by wind erosion in semiarid shrublands. Wind erosion depends on wind velocity (particularly during episodic, high-velocity winds) and on vegetation, which is generally sparse and spatially heterogeneous in semiarid ecosystems. Further, the vegetation cover can be rapidly and greatly altered due to disturbances, particularly fire. Few studies, however, have evaluated key temporal and spatial components of wind erosion with respect to (i) erosion rates on the scale of weeks as a function of episodic high-velocity winds, (ii) rates at unburned and burned sites, and (iii) within-site spatial heterogeneity in erosion. Measuring wind erosion in unburned and recently burned Chihuahuan desert shrubland, we found (i) weekly wind erosion was related more to daily peak wind velocities than to daily average velocities as consistent with our findings of a threshold wind velocity at approximately 7 m s(-1); (ii) greater erodibility in burned vs. unburned shrubland as indicated by erosion thresholds, aerodynamic roughness, and nearground soil movement; and (iii) burned shrubland lost soil from intercanopy and especially canopy patches in contrast to unburned shrubland, where soil accumulated in canopy patches. Our results are among the first to quantify post-fire wind erosion and highlight the importance of accounting for finer temporal and spatial variation in shrubland wind erosion. This finer-scale variation relates to semiarid land degradation, and is particularly relevant for predictions of contaminant resuspension and redistribution, both of which historically ignore finer-scale temporal and spatial variation in wind erosion.

BACKGROUND: Research has shown that support for families with children with autism spectrum disorder (ASD) in the United States has led to reduce parental stress. To better understand the situation in China, it is crucial to evaluate the current status of family support and provide clear evidence of the impact of family support on positive family outcomes. AIMS: This study aims to provide initial evidence to examine these interrelations among family support, parental stress, and family quality of life in mainland China. METHOD: A total of 226 parents of children with ASD completed two questionnaires (Beach Center Family Quality of Life (FQOL) Scale and the Family Support Scale for Chinese Children with ASD) and a demographic family information form. Structural equation modeling was used to examine the interrelation among parental stress, family support, and FQOL. RESULTS: Parents perceived a moderate to low level of family support and FQOL and high level of parental stress. Family support had a direct positive effect on FQOL (β = .54) and an indirect effect on FQOL through parental stress (β = .06). CONCLUSION: Resources should be devoted to establishing a family support system that promotes FQOL and buffers parental stress for families of children with ASD.

ABSTRACT The Ochoa series includes the uppermost Permian deposits of the southwestern United States. Most of the rocks included in the series are poorly exposed unfossiliferous evaporites. The well known subsurface section in and around the Delaware basin is described and illustrated by cross sections. A short chapter discusses theories on the origin and distribution of the characteristic evaporites.

On 20 March 2002, one of the most intense dust storms of the last decade struck Beijing: the total suspended particle (TSP) mass concentrations during the event reached 12 mg/m 3 and the visibility was reduced to less than 200 m. Variations in meteorological conditions in the boundary layer were monitored during the event, and changes in the physical properties and chemical composition of the aerosol also were studied. The dust storm was accompanied by a sharp and distinct increase in wind speed, a decrease in relative humidity, and increased mixing in the boundary layer due to turbulence. Back trajectory analysis and meteorological analysis showed that the main sources of dust particles that affected Beijing were most likely in southern Mongolia and the western part of Inner Mongolia, China. The amounts of Mg, Al, K, Ca, Ti, V, Cr, Mn, and Fe relative to one another were similar for the dust storm and nondust storm samples, and these elements occurred in near‐crustal proportions. In contrast, both the concentrations and enrichments relative to the crustal reference material for other elements, such as Se, Ni, Pb, Br, and Cu, were much higher during the dust storm than before or afterward. These elements, which are often associated with pollution emissions, apparently originated from distant sources upstream as well as from local sources in Beijing. Even though their enrichments were lower during the dust event, the concentrations of S, Zn, and Cl during the dust storm were higher than in the nondust periods; these results are further evidence that dusty air often contains higher levels of pollutants than nondusty air.

A detailed analysis of the data from a high sampling rate, multi-month reverberation mapping campaign, undertaken primarily at MDM Observatory with supporting observations from telescopes around the world, reveals that the Hbeta emission region within the broad line regions (BLRs) of several nearby AGNs exhibit a variety of kinematic behaviors. While the primary goal of this campaign was to obtain either new or improved Hbeta reverberation lag measurements for several relatively low luminosity AGNs (presented in a separate work), we were also able to unambiguously reconstruct velocity-resolved reverberation signals from a subset of our targets. Through high cadence spectroscopic monitoring of the optical continuum and broad Hbeta emission line variations observed in the nuclear regions of NGC 3227, NGC 3516, and NGC 5548, we clearly see evidence for outflowing, infalling, and virialized BLR gas motions, respectively.

PM 10 concentration data for Beijing were combined with trajectory clustering and potential source contribution function (PSCF) methods to identify the principal transport pathways and sources for high‐concentration aerosol events in the spring. Three major pathways exist: the main one passes over Kazakhstan, through desert and semi‐arid regions in southwestern Mongolia, and then through Inner Mongolia and onwards to Beijing. Four major potential sources were identified, these are: (1) border areas between Kazakhstan and China, (2) desert and semi‐desert regions in western Mongolia, (3) the Northern High Dust Desert and (4) the Loess Plateau of China. The pathways and sources for pollution aerosol also are associated with Asian dust emissions; this suggests a significant contribution of Asian dust to PM 10 pollution at Beijing.

Mothers' and fathers' responses to their children's spontaneous sibling conflicts were observed using a wireless microphone system. Eighty-eight two-child, two-parent families participated in three home observations. Secondborn children were 3 to 5 years of age and firstborn children were 2 to 4 years older. Associations between parents' enactment of three categories of conflict management strategies (passive nonintervention, child-centered management, and parental control) and sibling interaction quality varied according to children's ages, gender of the monitoring parent, and type of strategy used. Passive nonintervention was highly associated with the occurrence of subsequent conflict. Younger sibling dyads, in particular, behaved more antagonistically when their parents did not intervene. In contrast, older sibling dyads were less involved and less close when their mothers intervened in any way. Results suggest that relatively younger sibling dyads may benefit more than older dyads from parental intervention.