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This article examines the impact of previous local therapies, such as surgery and radiation therapy, on reconstruction outcomes after endoscopic endonasal surgery. The study reviews the experiences of a high-volume tertiary cancer care center to determine if prior radiation and/or surgery increases the risk of postoperative morbidity. The results suggest that prior radiation or surgery does not significantly increase the risk of complications, and the higher use of tunneled regional flaps in patients with a history of local therapy may contribute to this finding. Factors such as smoking history and the use of nonvascularized autografts were found to be significant predictors of postoperative complications. [Extracted from the article]

This article explores the role of race, ethnicity, and healthcare coverage in the presentation and outcome of endoscopic transsphenoidal surgery for pituitary adenomas at a diverse tertiary-care pituitary practice. The study found that there were significant differences in the presentation of surgical pituitary adenomas among patients with different ethnoracial backgrounds or healthcare coverage. However, surgical outcomes and complication rates did not differ significantly between these groups, suggesting that it may be possible to overcome presentation disparities within a single tertiary care pituitary practice. The findings highlight the importance of considering these factors in the treatment of pituitary adenomas. [Extracted from the article]

An analysis of the observed frequencies of the Raman-active longitudinal acoustic mode (LAM) bands of room-temperature crystalline n-alkanes in the chain-length range C33 to C246 indicates that, as the chains become longer, there is a significant decrease in interlayer interaction, this interaction being measured by the vibrational coupling between the ends of chains in adjoining layers. This conclusion is based mainly on LAM measurements on n-alkanes longer than 100 carbons that have recently become available. In the present analysis, the n-alkane crystals are modeled as collinear monatomic chains having end-to-end interactions to simulate interlayer interaction. One intrachain force constant (F) and one interchain coupling force constant (f ) were evaluated from the observed frequencies of the LAM-1 and LAM-3 bands for each of seven n-alkanes: C48, C62, C70, C72, C94, C150, and C192. As expected, the values found for F are essentially independent of chain length. However, the values of f were found to decrease in going to longer chains, contradicting the generally held view that the interlayer force constant is independent of chain length. The value of f is proportional to 1/n within experimental error. If we assume this proportionality, the observed Raman frequencies of the LAM-m modes can be accounted for quantitatively. This is not the case if f is assumed independent of chain length. The decrease in the interchain interaction with increasing chain length is attributed to an increase in the layer separation resulting from an increase in chain-end amplitudes associated with the low-frequency longitudinal vibrations of longer chains. [ABSTRACT FROM AUTHOR]

The vibrational density of states and isotropic Raman spectra of ensembles of conformationally disordered polymethylene-like skeletal chains have been computed numerically in the low-frequency CCC bending region below 600 cm-1. Chain lengths ranged from 8 to 25 atoms and the average trans-bond concentration varied from 0% to 100%. The calculated Raman spectra of the disordered chains are notable in that they display a progression of D-LAM-k bands. The existence of this progression indicates that the skeletal vibrations of the disordered-chain ensemble can, to some extent, be described in terms of a phase-angle model of the type normally associated with ordered chains. The applicability of a phase-angle model is also indicated by the frequency distribution of standing waves obtained from a harmonic analysis of the normal coordinates. [ABSTRACT FROM AUTHOR]

Detailed geometries and deuterium-isolated CH stretching frequencies are calculated for several different conformers of small n-alkanes at a number of levels of ab initio theory. The results of the calculations are carefully compared to experiment. The calculated frequencies fit a linear correlation to the calculated bond lengths with a mean absolute error of about 3 cm-1. The experimental frequencies fit this correlation more closely. Notable deviations from the correlation occur for the crowded C–H bonds that exist in gauche conformers. The changes in geometry on rotating a methyl group in propane are calculated and compared with experimental results on frequency shifts for n-alkane methyl groups. [ABSTRACT FROM AUTHOR]

Discusses a study which evaluated the surface and bulk chemical changes to blends exposed to subthreshold excimer laser fluences. Structural-modification mechanism for polyimide-doped poly(tetrafluoroethylene) at subthreshold fluences using 248 nanometer radiation; Details of the experiment; Effect of ablation on polyimide concentration.

Sensible and latent heat flux densities were estimated in a level vineyard, a northeast aspect vineyard and a southwest aspect vineyard in the Napa Valley of California using the eddy covariance and surface renewal methods. Surface renewal is theoretically not limited to level or extensively homogeneous terrain because it examines a more localized process of scalar exchange as compared with eddy covariance. Surface renewal estimates must be calibrated against eddy covariance data to account for unequal heating of the air parcels under a fixed measurement height. We calibrated surface renewal data against eddy covariance data in a level vineyard, and the calibration factor (α) was applied to the surface renewal measurements on the hillside vineyards. Latent heat flux density was estimated from the residual of the energy balance. In the level vineyard, the average daily actual evapotranspiration (ET) for the period of June through September was 2.4 mm per day. In the northeast aspect vineyard, the average daily ET was 2.2 mm per day, while in the southwest aspect vineyard it was 2.7 mm per day. The net radiation values for the level vineyard, the northeast aspect vineyard, and the southwest aspect vineyard were compared against the Ecosystem Water Program with good agreement. [ABSTRACT FROM AUTHOR]

Purpose. Although randomized trials suggest a survival benefit of adjuvant chemotherapy and radiation therapy (XRT) for gastric adenocarcinoma, its use in patients who undergo an extended lymphadenectomy is less clear. The purpose of this study was to determine if a survival benefit exists in gastric cancer patients who receive adjuvant XRT following resection with extended lymphadenectomy. Methods. The SEER registry was queried for records of patients with resected gastric adenocarcinoma from 1988 to 2007. Multivariable Cox regression models were used to assess independent prognostic factors affecting overall survival (OS) and disease-specific survival (DSS). Results. Of 15,060 patients identified, 3,208 (21%) received adjuvant XRT. Adjuvant XRT was independently associated with improved OS (HR 0.67, CI 0.64-0.71) and DSS (HR 0.69, CI 0.65-0.73) in stages IB through IV (M0). This OS and DSS benefit persisted regardless of the extent of lymphadenectomy. Furthermore, lymphadenectomy with >25 LN resected was associated with improved OS and DSS compared with <15 LN or 15-25 LN. Conclusion. This population based study shows a survival benefit of adjuvant XRT following gastrectomy that persists in patients who have an extended lymphadenectomy. Furthermore, removal of >25 LNs results in improved OS and DSS compared with patients who have fewer LNs resected. [ABSTRACT FROM AUTHOR]

Grapevines are grown on a range of soils and in different climates. Depending on the desired final product and method of harvesting, the trellis system, and hence vineyard architecture, varies dramatically. Consequently, the crop coefficients used to estimate vineyard evapotranspiration from reference evapotranspiration are less universal than for other crops. Evapotranspiration measurements are often limited because of a lack of fetch and unavailability of vine parameters required as input. In this paper, a new procedure based on surface renewal (SR) analysis was derived to estimate sensible heat flux over the grapevines. A two-dimensional sonic anemometer operating close to the canopy can provide the inputs required to estimate the sensible heat flux and the work of expansion of the air parcels under constant pressure. Regardless of the stability conditions, the SR estimates were comparable to those determined using the eddy covariance (EC) method providing a root-mean-square error of 14 W m−2 for all data. Thus, the procedure is low cost and makes SR a simpler method than EC to estimate latent heat flux as the residual of the energy balance equation in moderately tall and heterogeneous crops. The experiment was carried out at a site influenced by regional advection of sensible heat flux. [ABSTRACT FROM AUTHOR]

In this study, the authors analyze data on juvenile correctional facilities from the Performance-based Standards for Youth Correction and Detention Facilities project to predict victimization and fear among individual juvenile inmates. The authors estimate multilevel models using both facility and individual level factors. Their results depart from prior research efforts, which have focused primarily on either an importation or a deprivation model for explaining facility misconduct. In contrast, the authors find evidence of a third model that merges individual- and facility-level variables to consider individual youth's perceptions of facility rules and practices. They find that the best predictors of victimization are youths' understanding of facility rules as well as their perceptions of school quality and staff helpfulness. [ABSTRACT FROM AUTHOR]

Experiments to measure the evapotranspiration of an improved, irrigated pasture were conducted at the University of California, Davis, CA field station and over a commercial irrigated pasture on Twitchell Island in the Sacramento-San Joaquin River Delta using the surface renewal (SR) method. In Davis, the SR method was used to determine well-watered crop evapotranspiration (ETc) over short grass, and the results were compared with the ASCE-EWRI standardized reference evapotranspiration (ET0) for a short canopy to establish that a crop coefficient Kc=1.00 is appropriate for estimating well-watered pasture ETc. In the Twitchell Island study, surface renewal was used to determine the actual evapotranspiration (ETa) from a commercial pasture. A stress coefficient of Ks=ETa/ET0≈0.90 was observed during the high ET period (ET0>7 mm day-1) from about mid-June through mid-July for the Twitchell Island pasture. Otherwise, the pasture was mainly unstressed, so the Ks=1.0. Thus, assuming no future changes in irrigation management, using ET0 from Twitchell Island, a Kc=1.00, and Ks=1.00 will provide good estimates of ETa during low to moderate ET periods and Ks≈0.90 should be used when ET0>7.0 mm day-1. In general, a thermocouple for SR measurements costs about $100, whereas the price for a sonic anemometer varies between $3,000 and $20,000, so the SR method provides a low-cost method to measure ETa. [ABSTRACT FROM AUTHOR]

The article focuses on the movement known as third wave feminism. It explains that the movement emphasizes personal narratives, action, and an inclusive and nonjudgmental approach. The book, in two volumes, "The Women's Movement Today: An Encyclopedia of Third-Wave Feminism" by Leslie L. Heywood is explored and the feminist Rebecca Walker is mentioned. The influence of mass media and technological innovations on third wave feminism are examined and the differences between the movement and the feminist movement of the previous generation are discussed.

Khan's review is a brief summary of the complex field of study revolving around bone marrow toxicity and leukemogenesis observed in people chronically exposed to benzene. These comments are intended to demonstrate the use of the Kahn review as a launching pad for an in-depth analysis of the several related areas that must be fully explored to understand benzene-related diseases. The accumulated evidence demonstrates that benzene-induced bone marrow damage results from the production of hematotoxins that are metabolic products of benzene metabolism. The metabolism of benzene is described with respect to the formation benzene metabolites with emphasis on phenol and hydroquinone, which are the major metabolites, the significance of the formation of glutathione conjugates, the activity of NAD(P)H:quinone oxidoreductase (NQO1), and the ring opening products. Results are shown suggesting that oxidative stress induced by benzene metabolites is likely to be a significant factor in damaging DNA in bone marrow cells. Although a variety of effects on bone marrow can be demonstrated it is not yet clear which metabolites are most important in either benzene-induced aplastic anemia or leukemia. Benzene metabolism alone is insufficient to fully describe benzene toxicity. The impact of benzene metabolites on bone marrow cells must be fully explored to determine how benzene exposure can result in decreased viability or genetic toxicity to cells in the bone marrow. [ABSTRACT FROM AUTHOR]

This article presents a letter from the editors, which evaluates feminist theory, what feminist theory brings to political thought, and the resurgence of theorizing the democratic theory. The editors discuss how democratic theory is being evaluated by world politicians on how it can be presented in a less manipulative fashion and how the scope of the feminist theory can be implemented into democratic theory.

Crop evapotranspiration (ETc) was measured over a clean-cultivated, mature navel orange orchard with microsprinkler irrigation located near Lindsay, California. Hourly mean latent heat flux density was determined as the residual of the energy balance equation with measured net radiation, soil heat flux density and sensible heat flux density estimated using the surface renewal method. The ETc was compared with ETo calculated using hourly weather data and the ASCE-EWRI Penman-Monteith equation. Following pruning and topping of the trees in the spring of 2001, the Kco values slowly increased as the canopy developed in the following season. An average Kco=0.82 was observed. In the following year, the mean summertime value increased to about Kco=0.95, and in 2003 and 2004, the summertime value averaged near Kco=1.00, which is somewhat higher than observed for drip irrigated trees in southwestern Arizona and considerably higher than reported in the widely used Food and Agricultural Organization of the United Nations publications that were based on infrequent surface irrigation. [ABSTRACT FROM AUTHOR]

Abstract Breast cancer is a common disease in the community. Its incidence is increasing but its mortality is falling. New therapeutic approaches based on a biological understanding of the disease are being investigated to improve the outcome. These include the areas of chemo­prevention and therapy in the adjuvant and advanced settings, and some derive from a better understanding of the biology of breast cancer. New prognostic indicators are being studied to enable adjuvant chemotherapy to be directed towards those most likely to benefit. Trastuzumab was the first of the new targeted therapies to be introduced into routine practice. Several other agents targeting a variety of receptors and cell pathways, such as the epidermal growth factor receptor, the vascular epithelial growth factors and various intracellular tyrosine kinase mediated pathways, are under investigation. Increasing attention is being placed on evidence-based supportive care, both for control of symptoms such as hot flushes and for psychosocial problems such as anxiety and depression. (Intern Med J 2004; 34: 266−269) [ABSTRACT FROM AUTHOR]

This article contests the conservative revisionism that emphasizes the importance of traditional families, pietistic religion, individual moral virtue, and small government for undergirding democratic self-government. The first part exposes the conservative misreading of American history and political theory. The second part uses the civic engagement of middle- and upper-class women in 19th-century America to construct a progressive alternative to conservative narratives. It shows that women did not stay home and focus on the family during the 19th century but instead entered civil society to address the problems created by industrialization, formed social reform movements, built institutions to pursue a social justice agenda, and demanded that the government take an active role in solving public problems. Their civic engagement built on and created social capital, grew out of and produced a sense of civic virtue (defined as public-spiritedness), and resulted in the demand for progressive government. [ABSTRACT FROM AUTHOR]

Michael Sandel's Democracy's Discontent strives to contribute to the project of "democratic theory," which aims to bring people together across ideological differences. Sandel wants to revitalize citizenship by uniting religious conservatives and those committed to a more just political economy through an appeal to the American tradition of civic republicanism. However, his project is fundamentally incoherent. First, Sandel's narrative conflates the republican and religious aspects of the American founding, ignoring the fact that civic republican political theory actually developed in direct opposition to the ideal of a Christian polity. Second, his version of civic republicanism deviates from the historic tradition in a way that renders it much more conservative than it actually was and might still be. Third, his reading of American history consistently highlights conservative themes. Consequently, Sandel ultimately undercuts the progressive aspects of his own vision, detracting from rather than contributing to the transideological aspirations of "democratic theory." [ABSTRACT FROM AUTHOR]

Points out that 'The Eighteenth Brumaire of Louis Bonaparte,' by Karl Marx and Frederick Engels embraces the basic tenets of the citizen-soldier tradition. Citizen-soldier tradition of civic republicanism; Role of the citizen-soldier ideal in the French Revolution of 1789; Military defeat of republicanism; Importance of republican political principles backed up by the force of arms.

The article reports that researcher James Burk's view that militaries in democracies must help sustain democratic values can be used to introduce a new dimension into debates about women in the military. Debates about gender integration in the U.S. armed forces tend to polarize proponents who emphasize democratic values related to women's rights and military effectiveness. The article concludes that any changes should be closely studied and evaluated in terms of their impact on military effectiveness and effect on democratic values.

Explores gender radicalism and civil society. Definition of civil society; Reduction of democracy to an active civil society; Impact of the deprivation of rights to suffrage to women on their political activity.

Highlights the Benzene-State-of-the Science Workshop on the physiological effects of chronic exposure to benzene. Correlation between leukemia and benzene exposure; Details on the metabolism and pharmacokinetics of benzene; Types of mercapturic acids derived from benzene.

Potential links between personal and sociocultural aspects of body-image concerns and sets of behavioral and emotional symptoms associated with eating disorders were explored within a self-discrepancy theory framework. It was predicted that actual:ideal body-image discrepancies from one's own standpoint would be related to symptoms reflecting feelings like dissatisfaction and actual:ought body-image discrepancies from a societal standpoint would be related to symptoms reflecting feelings like anxiety. The Bodies Questionnaire, Eating Disorder Inventory, and demographic information were completed by 196 undergraduate women volunteers. Results generally supported the predictions, although the effects were small. Perceived body-image discrepancies from sociocultural prescriptions for slimness and appearance are more closely associated with symptoms reflecting failures to achieve these standards than with symptoms reflecting efforts to attain them. In addition, the contribution of personal ideals to bulimic symptomatology and body dissatisfaction includes concerns about body attributes not associated with weight. Possible clinical applications are discussed. [ABSTRACT FROM AUTHOR]

The article presents abstracts related to the U.S. armed forces. They include "The Eighth Army's Combat Readiness Before Korea: A New Appraisal," by Thomas E. Hanson, "The Citizen-Soldier Tradition and Gender Integration of the U.S. Military," by R. Claire Snyder and "The Multicultural Military: Military Service and the Acculturation of Latinos and Anglos," by David L. Leal.

Presents a reply to comments on the article 'Accuracy of ab initio C-H Bond Length Differences and Their Correlation With Isolated C-H Stretching Frequencies.'

Presents an abstract of the study 'Aspects of Sintering Barium Hexaferrite with SiO[sub2], Al [sub2]O[sub3], CaCO[sub3], and Y[sub6]Fe[sub10]O[sub24] Additions for Microwave Applications,' by J.G. Fagan, R.L. Snyder, C. Hach, L. Jones, J.B. Ings, J. May and J.J. Simmins.

We report on the fabrication of Josephson junctions using the topological crystalline insulator Pb0.5Sn0.5Te as the weak link. The properties of these junctions are characterized and compared to those fabricated with weak links of PbTe, a similar material yet topologically trivial. Most striking is the difference in the ac Josephson effect: junctions made with Pb0.5Sn0.5Te exhibit a rich subharmonic structure consistent with a skewed current-phase relation. This structure is absent in junctions fabricated from PbTe. A discussion is given on the origin of this effect as an indication of novel behavior arising from the topologically nontrivial surface state. [ABSTRACT FROM AUTHOR]

Nucleotide-rich yeast extract (YN) was investigated for effects on growth performance, jejunal physiology, and cecal microbial activity in Eimeria -challenged broiler chickens. A total of 360-day-old male chicks (Ross × Ross 708) were placed on floor pens and provided a corn–soybean meal-based diet without or with YN (500 g/MT; n = 12). On d 10, 6 replicates per diet were orally administered with 1 mL of E. acervulina and E. maxima sporulated oocysts and the rest (non-challenged control) were administered with 1 mL of distilled water. On d 15, 5 birds/pen were then necropsied for intestinal lesion scores, histomorphology and cecal digesta pH, short chain fatty acids (SCFA), and microbial community using Illumina Miseq platform. Supplemental YN improved (P = 0.01) Feed conversion ratio (FCR) during the prechallenge phase (d 0 to 10). In the postchallenge period (d 11 to 15), Eimeria depressed (P < 0.05) Body weight gain (BWG) relative to non-challenged birds, whereas YN-fed birds had a higher (P = 0.05) BWG compared to that of non-YN-fed birds. There was an interaction between YN and Eimeria on jejunal villi height (VH) (P = 0.001) and expression of cationic amino acid transporter 1(CAT1) (P = 0.04). Specifically, in the absence of Eimeria, YN-fed birds had a shorter VH (892 vs. 1,020 μm) relative to that of control but longer VH (533 vs. 447 μm) in the presence of Eimeria. With respect to CAT1, YN-fed birds had a higher (1.65 vs. 0.78) expression when subjected to Eimeria than when not challenged. Independently, Eimeria decreased (P < 0.01) the jejunal expression of maltase, Na glucose transporter 1 and occludin genes, ceca digesta abundance of genus Clostridium cluster XlVa and Oscillibacter but increased (P < 0.01) jejunal proliferating cell nuclear antigen and interleukin 10. Interaction between YN and Eimeria was observed for ceca digesta pH (P = 0.04) and total SCFA (P = 0.01) such that YN increased SCFA in the absence of Eimeria but reduced SCFA and increased pH in the presence of Eimeria. In summary, Eimeria impaired performance and gut function and shifted gut microbiome; YN improved performance independently, attenuated Eimeria damage on indices of gut function, and modulated cecal microbiome. [ABSTRACT FROM AUTHOR]

The distributions of conformational defects that exist in the high-temperature phase II (also referred to as the hexagonal or rotator phase) of the crystalline n-alkanes C21 and C29 have been measured by an infrared CD2-substitution technique and have been accounted for in terms of a lattice model that provides freedom for longitudinal displacement of the chains. The defects consist almost entirely of gtg’ kinks distributed nonuniformly along the chain. The uneven distribution is indicated in the variation in the concentration of gauche bonds measured at various sites along the chain. The highest concentration is at the chain ends, and the concentrations at interior sites decrease exponentially in going toward the middle. To explain the distribution we used a modification of a lattice model that had been successfully applied to the lipid bilayer. Comparison of observed distributions with those computed from the model indicates that the factors that determine the shape of the distribution are quite different in the n-alkane and bilayer cases. For the bilayer, the dominant factor is the variation in the lateral density of chains; for the n-alkane, the dominant factor is associated with longitudinal displacement of the chains. [ABSTRACT FROM AUTHOR]

Presents a study that produced nickel ferrites by the rf plasma deposition technique. Powder x-ray diffraction linewidth measurements; Comparison of the aerosol prepared samples with the solid state reacted bulk materials; Mössbauer spectra of the aerosol powders.

The article presents a case of a 58-year old woman with chronic lymphocytic leukemia. She had a circulating cryoglobulin, with immunofixation of the cryoprecipitate. She has undergone a renal biopsy which revealed cryoglobulinemic glomerulonephritis. This situation is a rare finding in the setting of chronic lymphocytic leukemia.

Recently presented climate change scenarios include increasing demand for water, due to both increase in temperature and variations in precipitation pattern. Since crop water requirements are related to climate and irrigation scheduling depends on crop evapotranspiration (ETc), it is crucial to have tools that allow the estimation of ETc in a reliable way. ETc is often calculated as the product of two factors, the reference evapotranspiration (ETo) and crop coefficient (Kc) values that convert ETo to ETc. This paper reviews Kc values, measured in different parts of the world and in different climates, with the aim to offer a practical tool for selecting the most appropriate Kc values for water balance irrigation scheduling, which result in more efficient irrigation. More than 100 scientific papers were studied and summarized in a report, accompanied by an extensive Kc database. The Kc report and database are available in the "Supplemental Data" section of this paper. [ABSTRACT FROM AUTHOR]

Structure functions are used to study the dissipation and inertial range scales of turbulent energy, to parametrize remote turbulence measurements, and to characterize ramp features in the turbulent field. Ramp features are associated with turbulent coherent structures, which dominate energy and mass fluxes in the atmospheric surface layer. The analysis of structure functions to identify ramp characteristics is used in surface renewal methods for estimating fluxes. It is unclear how commonly observed different scales of ramp-like shapes (i.e., smaller ramps and spikes embedded in larger ramps) influence structure function analysis. Here, we examine the impact of two ramp-like scales on structure function analysis using artificially generated data. The range of time lags in structure function analysis was extended to include time lags typically associated with isotropic turbulence to those larger than the ramp durations. The Van Atta procedure (Arch Mech 29:161-171, ) has been expanded here to resolve the characteristics of two-scale ramp models. This new method accurately, and in some cases, exactly determines the amplitude and duration of both ramp scales. Spectral analysis was applied to the structure functions for a broad range of time lags to provide qualitative support for the expanded Van Atta procedure results. The theory reported here forms the foundation for novel methods of analyzing turbulent coherent structures. [ABSTRACT FROM AUTHOR]

Ramp features in the turbulent scalar field are associated with turbulent coherent structures, which dominate energy and mass fluxes in the atmospheric surface layer. Although finer scale ramp-like shapes embedded within larger scale ramp-like shapes can readily be perceived in turbulent scalar traces, their presence has largely been overlooked in the literature. We demonstrate the signature of more than one ramp scale in structure functions of the turbulent scalar field measured from above bare ground and two types of short plant canopies, using structure-function time lags ranging in scale from isotropic to larger than the characteristic coherent structures. Spectral analysis of structure functions was used to characterize different scales of turbulent structures. By expanding structure function analysis to include two ramp scales, we characterized the intermittency, duration, and surface renewal flux contribution of the smallest (i.e., Scale One) and the dominant (i.e., Scale Two) coherent structure scales. The frequencies of the coherent structure scales increase with mean wind shear, implying that both Scale One and Scale Two are shear-driven. The embedded Scale One turbulent structure scale is ineffectual in the surface-layer energy and mass transport process. The new method reported here for obtaining surface renewal-based scalar exchange works well over bare ground and short canopies under unstable conditions, effectively eliminating the α calibration for these conditions and forming the foundation for analysis over taller and more complex surfaces. [ABSTRACT FROM AUTHOR]

The distribution and trends in reference evapotranspiration (ETo) are extremely important to water resources planning for agriculture, and it is widely believed that rates of ETo will increase with global warming. This is a big concern in China, where water deficits are common in the North China Plain (NCP). In this study, Penman-Monteith reference evapotranspiration at 26 meteorological stations during 1961–2006 in and around the NCP was calculated. The temporal variations and spatial distribution of ETo were analyzed and the causes for the variations were discussed. The results showed that: (1) the NCP was divided into two climatic regions based on aridity values: a semiarid region that accounts for 69% of the area and subhumid regions that made of the remaining area; (2) over the entire NCP, the highest annual ETo occurred in the central and western areas and the lowest total ETo was observed in the east. Comparing the mean monthly ETo and annual ETo distributions, the high ETo values from May through July mainly determined the annual ETo distribution; (3) for the whole NCP, annual ETo showed a statistically significant decrease of 11.92 mm/decade over the 46 years of data collection in the NCP or approximately a 5% total decrease compared to the ETo values in 1961; (4) to determine which variable has the greatest effect on the decrease in ETo, decadal changes were observed for daily values of maximum air temperature (+0.16°C), minimum air temperature (+0.35°C), net radiation (-0.13 MJ m-2), and mean wind speed (-0.09 m s-1). These results indicate that the decreasing net radiation and wind speed had a bigger impact on ETo rates than the increases observed by the maximum and minimum temperatures. [ABSTRACT FROM AUTHOR]