bluuebunny/crossref_metadata_2025 huggingface dataset:
Translational Therapeutics in Genetically Engineered Mouse Models of Cancer
Authors: Olive Kenneth P. , Politi Katerina
Published: February 2014

Advances in knowledge of the molecular alterations of human cancers, refinements in technologies for the generation of genetically engineered mouse models (GEMMs), and the development of cancer therapies have accelerated in recent years. Progress in these fields provides the foundation for clinically relevant studies to be performed in GEMMs, through which it is possible to glean information on drug efficacy and to identify determinants of sensitivity and resistance to drugs and drug combinations. GEMMs used in pre-, co-, and postclinical studies must closely recapitulate the genetics, histopathology, and response to therapy of the human disease. Prevention and intervention trials can be designed in GEMMs to test the effects of drugs on tumor initiation, regression, and progression. Given their complexity, careful consideration of the infrastructure requirements and practical aspects of each individual experiment, including enrollment, tumor monitoring, and dose and schedule, must be considered in the design of therapeutic studies in GEMMs. Advantages of GEMMs include the ability to rapidly perform drug efficacy studies in a defined genetic background, the ease of pharmacodynamic and pharmacokinetic assessments, and the possibility of experimentally manipulating model systems to address questions that cannot be addressed in patients. In light of these features, GEMMs are useful tools for translational studies to inform clinical trials in cancer patients.
Mouse to Human Blood-Based Cancer Biomarker Discovery Strategies
Authors: Hanash Samir M. , Taguchi Ayumu
Published: February 2014

There is an urgent need for noninvasive molecular tests to assist in the detection of cancers. There is additionally a need for prognostic and predictive markers and for monitoring for disease recurrence. The improved understanding of molecular features of common cancers and the availability of genetically engineered mouse models (GEMMs) of cancer have resulted in increased interest in the application of mouse models to the discovery of cancer biomarkers relevant to humans. Unlike humans, mouse models allow sampling of tumor and host tissues and biological fluids at defined time points in the course of tumor development and progression. Interrogation of the genome, transcriptome, proteome, and metabolome of tumors and biological fluids from mouse models engineered to recapitulate human tumors makes it possible to apply a systems approach to define biomarker signatures from the earliest stages of tumor development to advanced stages and metastasis and signatures reflective of driver genes and pathways.
Genetic Labeling of Neurons in Mouse Brain
Authors: Huang Z. Josh , Taniguchi Hiroki , He Miao , Kuhlman Sandra
Published: February 2014

Mammalian central nervous systems consist of highly diverse types of neurons, which are the functional units of neural circuits. To understand the organization, assembly, and function of neural circuits, it is necessary to develop and to improve technologies that allow efficient and robust visualization of neurons in their native environment in vivo. Here we discuss various genetic strategies for achieving specific and robust neuron labeling in mice.
Imaging Biological Samples with Atomic Force Microscopy
Authors: de Pablo Pedro J. , Carrión-Vázquez Mariano
Published: February 2014

Atomic force microscopy (AFM) is an invaluable tool both for obtaining high-resolution topographical images and for determining the values of mechanical and structural properties of specimens adsorbed onto a surface. AFM is useful in an array of fields and applications, from materials science to biology. It is an extremely versatile technique that can be applied to almost any surface-mounted sample and can be operated in ambient air, ultrahigh vacuum, and, most importantly for biology, liquids. AFM can be used to explore samples ranging in size from atoms to molecules, molecular aggregates, and cells. Individual biomolecules can be viewed and manipulated at the nanoscale, providing fundamental biological information. In particular, the study of the mechanical properties of biomolecular aggregates at the nanoscale constitutes an important source of data to elaborate mechanochemical structure/function models of single-particle biomachines, expanding and complementing the information obtained from bulk experiments.
Apple Peel and Carboxymethylcellulose‐Based Nanocomposite Films Containing Different Nanoclays
Authors: Shin So‐Hyang , Kim Sung‐Jin , Lee Soo‐Hyun , Park Ki‐Moon , Han Jaejoon
Published: February 2014

Biodegradable packaging films were developed from polymeric blends of apple peel powder (APP) and carboxymethylcellulose (CMC), into which different nanoclays were incorporated to produce a nanocomposite film. After first estimating the barrier and mechanical properties of 4 different biopolymer films (CMC, methylcellulose, gelatin, and polylactide), CMC was chosen as the best film‐forming solution. Three different nanoclays (Cloisite Na+, 30B, and 20A) were subsequently dispersed in a CMC film solution to improve the barrier and physical properties of the final CMC nanocomposite films. The structures of the exfoliated CMC nanocomposite films were characterized using X‐ray diffraction (XRD) to determine the most efficient nanoclay type, with Cloisite Na+ addition being found to demonstrate the greatest improvement in the barrier and mechanical properties of the film. Finally, the CMC and Cloisite Na+ solution were thoroughly blended with APP using a high‐pressure homogenization (HPH) process to develop biopolymer nanocomposite films, which were then characterized using XRD and Fourier transform infrared spectroscopy. The HPH treatment significantly improved the film‐forming ability by increasing the dispersity of APP in the CMC nanocomposites, as well as having various other effects on the physical properties. These nanocomposite films can be viewed as an alternative solution for the use of agricultural biomass in developing environmentally friendly packaging materials.

Practical Application

Cloisite Na+ nanoclay noticeably improved the barrier and elongation properties of a biopolymer film. High‐pressure homogenization successfully blended apple peel powder with carboxymethylcellulose to develop a nanocomposite film. The apple peel and CMC‐based nanocomposite films that were developed could be used as a novel biodegradable packaging material.
Chinese Workfarism: Logics and Realities of the Work–Welfare Governance Model
Authors: Sun Xiaodong
Published: February 2014

Given the fundamental disparities between China and the west in political structures, social values, policy regimes, and problem loads, it is meaningful to use “workfare” as a challenging analytical standpoint and detect that China had created unique workfare regimes to build up the past state‐socialism and the present market‐socialism. In the era of state‐socialism, the dual‐track welfare system, apparently adopting aninstitutionalapproach to the city and aresidualapproach to the countryside, was purposely integrated with the segregated urban‐rural work system, constituting a China‐specific workfare regime in which the whole workforce was included and effectively organized into the socio‐economic order. Under market‐socialism that appears as an awkward hybrid, the work‐welfare governance model is being gradually transformed into a pragmatic, much marketized one, though without idealogical legitimacy as well as a clear‐cut vision. On the one hand, employment differentiation and income disparity resulted from a strategic shift from the “reform‐without‐losers” stage to the “reform‐with‐losers” stage in the labor market, together with a large scale rural‐to‐urban labor migration, are structuring a market‐oriented, stratified employment system. On the other hand, while being a welfare laggard, China's productivist, status‐segregated welfare system is taking shape owing to a set of welfare reforms along the line of marketization and societalization. All these changes would imply that China is converging towards a neo‐liberal regime in which the role of the state is residual to the market.
Analysis of As‐ and Hg‐Species in Metal‐Resistant Oral Bacteria, by Imaging ToF‐SIMS
Authors: Nygren Håkan , Dahlén Gunnar , Malmberg Per
Published: February 2014

Bacterial strains were isolated from the oral cavity of healthy volunteers and grown in the presence of Hg‐ions (1–10 ppm) or arsenate ions at concentrations of 0.1–1.0%. To elucidate how bacteria take up and transform toxic metals inside the cells, we performed ion imaging and depth profiling with time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS). This analysis relies on the use of a pulsed ion beam to ionize surface molecules that can be extracted into a time‐of‐flight mass spectrometer. By combining the pulsed ion beam with another ion beam in direct current (DC) mode, depth profiles are obtained as a result of consecutive removal of surface layers. The spatial resolution of the depth profile along the y‐axis is in the range of a few nanometres, and the spatial resolution along the x‐ and z‐axes is in the μm range. The ToF‐SIMS analysis was performed on crude biofilms of bacteria air‐dried at aluminium foil surfaces, allowing subcellular resolution along the y‐axis. The mercury ions were found transformed to methylmercury preferably in the periplasmic space, and the arsenate ions were found reduced to arsenite inside the cells, close to the cell membrane. The data are discussed in relation to current concepts in bacterial resistance to metals and antibiotics.
An Outbreak of Pyrimethamine Toxicity in Patients with Ischaemic Heart Disease in Pakistan
Authors: Khan Assir Muhammad Zaman , Ahmad Hafiz Ijaz , Akram Javed , Yusuf Noshin Wasim , Kamran Umair
Published: February 2014

We investigated an outbreak of darkening of skin, bleeding from multiple sites, leucopenia and thrombocytopenia in ischaemic heart disease patients. Case patients were defined as patients who had received medicines from the pharmacy of Punjab Institute of Cardiology between 1 December 2011 and 12 January 2012 and who developed any one of the following: darkening of skin, bleeding from any site, thrombocytopenia and leucopenia. Clinical and drug‐related data were abstracted. All 664 case patients had received iso‐sorbide‐mono‐nitrate contaminated with about 50 mg of pyrimethamine, and 151 (23%) died. The median age of 117 patients admitted at Jinnah Hospital Lahore was 57 years (range, 37–100) and 92 (79%) were male. The median time from intake of medicine to presentation was 37 days (range 13–72). Symptoms and signs included bleeding (in 95% of the patients), skin hyperpigmentation (in 61%), diarrhoea (in 53%) and abdominal pain (in 48%). At presentation, the median white cell count was 2.3 × 109/L (range, 0.1 × 109–16.0 × 109), the median hemoglobin concentration was 109 g/L (range 58–169) and the median platelet count was 18 × 109/L (range, 0 × 109–318 × 109). Bone marrow examination revealed trileneage dysplasia and severe megaloblastosis. The predictors of mortality included presentation prior to 15 January 2012, age more than 57 years, hypotension and leukocyte count less than 1.5 × 109/L. None of the patients who died received Calcium folinate because all deaths occurred prior to contaminant identification. We describe an outbreak of pyrimethamine toxicity in ischaemic heart disease patients receiving medicines from a single pharmacy due to accidental contamination of iso‐sorbide mono‐nitrate tablets at industrial level. Late recognition of illness resulted in high mortality.
Reliability measures in item response theory: Manifest versus latent correlation functions
Authors: Milanzi Elasma , Molenberghs Geert , Alonso Ariel , Verbeke Geert , De Boeck Paul
Published: February 2014

For item response theory (IRT) models, which belong to the class of generalized linear or non‐linear mixed models, reliability at the scale of observed scores (i.e., manifest correlation) is more difficult to calculate than latent correlation based reliability, but usually of greater scientific interest. This is not least because it cannot be calculated explicitly when the logit link is used in conjunction with normal random effects. As such, approximations such as Fisher's information coefficient, Cronbach's α, or the latent correlation are calculated, allegedly because it is easy to do so. Cronbach's α has well‐known and serious drawbacks, Fisher's information is not meaningful under certain circumstances, and there is an important but often overlooked difference between latent and manifest correlations. Here, manifest correlation refers to correlation between observed scores, while latent correlation refers to correlation between scores at the latent (e.g., logit or probit) scale. Thus, using one in place of the other can lead to erroneous conclusions. Taylor series based reliability measures, which are based on manifest correlation functions, are derived and a careful comparison of reliability measures based on latent correlations, Fisher's information, and exact reliability is carried out. The latent correlations are virtually always considerably higher than their manifest counterparts, Fisher's information measure shows no coherent behaviour (it is even negative in some cases), while the newly introduced Taylor series based approximations reflect the exact reliability very closely. Comparisons among the various types of correlations, for various IRT models, are made using algebraic expressions, Monte Carlo simulations, and data analysis. Given the light computational burden and the performance of Taylor series based reliability measures, their use is recommended.
Ethnic and Racial Identity in Adolescence: Implications for Psychosocial, Academic, and Health Outcomes
Authors: Rivas‐Drake Deborah , Seaton Eleanor K. , Markstrom Carol , Quintana Stephen , Syed Moin , Lee Richard M. , Schwartz Seth J. , Umaña‐Taylor Adriana J. , French Sabine , Yip Tiffany ,   Ethnic and Racial Identity in the 21st Century Study Group
Published: February 2014

The construction of an ethnic or racial identity is considered an important developmental milestone for youth of color. This review summarizes research on links between ethnic and racial identity (ERI) with psychosocial, academic, and health risk outcomes among ethnic minority adolescents. With notable exceptions, aspects of ERI are generally associated with adaptive outcomes. ERI are generally beneficial for African American adolescents' adjustment across all three domains, whereas the evidence is somewhat mixed for Latino and American Indian youth. There is a dearth of research for academic and health risk outcomes among Asian American and Pacific Islander adolescents. The review concludes with suggestions for future research on ERI among minority youth.
Equity in Education Expenditure in Thailand
Authors: Cuesta José , Madrigal Lucia
Published: February 2014

This article analyses the distributional effects of education spending across regions of Thailand, a country that purportedly seeks to reduce regional welfare disparities through decentralisation. It finds that public expenditure on education is neither progressive nor pro‐poor, although there are sizeable regional differences, driven by the pro‐rich distributional profiles of public tertiary education spending and public transfers to private education. Policy‐wise, these results suggest that the current decentralised allocation of educational spending is not consistent with an equity‐enhancing goal.
Selection of a mineralocorticoid receptor antagonist for patients with hypertension or heart failure
Authors: Iqbal Javaid , Parviz Yasir , Pitt Bertram , Newell‐Price John , Al‐Mohammad Abdallah , Zannad Faiez
Published: February 2014

Clinical trials have demonstrated morbidity and mortality benefits of mineralocorticoid receptor antagonists (MRAs) in patients with heart failure. These studies have used either spironolactone or eplerenone as theMRA. It is generally believed that these two agents have the same effects, and the data from studies using one drug could be extrapolated for the other. National and international guidelines do not generally discriminate between spironolactone and eplerenone, but strongly recommend using anMRAfor patients with heart failure due toLVsystolic dysfunction and post‐infarctLVsystolic dysfunction. There are no major clinical trials directly comparing the efficacy of these two drugs. This article aims to compare the pharmacokinetics and pharmacodynamics of spironolactone and eplerenone, and to analyse the available data for their cardiovascular indications and adverse effects. We have also addressed the role of special circumstances including co‐morbidities, concomitant drug therapy, cost, and licensing restrictions in choosing an appropriateMRAfor a particular patient, thus combining an evidence‐based approach with personalized medicine.
Predicting survival in heart failure: validation of the MAGGIC heart failure risk score in 51 043 patients from the Swedish Heart Failure Registry
Authors: Sartipy Ulrik , Dahlström Ulf , Edner Magnus , Lund Lars H.
Published: February 2014

Aims

The aim of this study was to evaluate the performance of a recently developed risk score for mortality in heart failure by external validation in a national heart failure registry.

Methods and results

From 13 routinely available patient characteristics, the Meta‐analysis Global Group in Chronic Heart Failure (MAGGIC) constructed a risk score for prediction of mortality in heart failure. We included 51 043 patients from the national Swedish Heart Failure Registry and calculated the MAGGIC risk score for each patient. The outcome measure was 3‐year mortality. The predicted probability of death obtained from the calculated risk score was compared with the observed 3‐year mortality, and model discrimination and calibration were assessed by formal tests and graphical means. The overall 3‐year mortality in the study population was 39.4% and the MAGGIC project heart failure risk score predicted mortality was 36.4% (observed to expected ratio: 1.08). Discrimination was excellent overall (C index = 0.741). The difference between the model‐predicted and the observed 3‐year mortality in the six risk groups varied between 5% and −12%. Calibration plots demonstrated slight overprediction for the lowest risk patients, and underprediction in high risk patients.

Conclusion

The MAGGIC project heart failure risk score demonstrated an excellent ability to categorize patients in separate risk strata. Although the predicted 3‐year mortality risk was higher in low risk groups and lower in high risk groups compared with the observed 3‐year mortality in the Swedish Heart Failure Registry, the MAGGIC project heart failure risk score performed well in a large nationwide contemporary external validation cohort.
Cardiorespiratory fitness and risk of heart failure: a population‐based follow‐up study
Authors: Khan Hassan , Kunutsor Setor , Rauramaa Rainer , Savonen Kai , Kalogeropoulos Andreas P. , Georgiopoulou Vasiliki V. , Butler Javed , Laukkanen Jari A.
Published: February 2014

Aim

To examine the relationship between cardiorespiratory fitness (CRF) and risk of incident heart failure (HF).

Methods and results

Cardiorespiratory fitness, as measured by maximal oxygen uptake (VO2max), was assessed at baseline in a prospective cohort of 1873 men aged 42–61 years without HF or chronic respiratory disease. During a mean follow‐up of 20.4 years, 152 incident HF events were recorded. Within‐person variability was calculated using data from repeat measurements taken 11 years apart. The age‐adjusted hazard ratio (HR) per unit increase (1 mL/kg/min of VO2max) in CRF was 0.89 [95% confidence interval (CI) 0.86–0.93], which was minimally attenuated to 0.94 (95% CI 0.90–0.98) after further adjustment for established HF risk factors (body mass index, systolic blood pressure, history of cardiovascular disease, diabetes, heart rate, and LV hypertrophy) and incident coronary events as a time‐varying covariate. In a comparison of extreme quartiles of CRF levels (VO2max ≥35.4 vs. ≤25.7 mL/kg/min), the corresponding HRs were 0.27 (0.15–0.50) and 0.48 (0.25–0.92), respectively. Each 1 MET (metabolic equivalent of oxygen consumption) increment in CRF was associated with a 21% (7–33%) reduction in multivariable adjusted risk of HF. Addition of CRF to a HF risk prediction model containing established risk factors did not significantly improve risk discrimination (C‐index change = 0.0164, P = 0.07).

Conclusions

In this Finnish population, there is a strong, inverse, and independent association between long‐term CRF and HF risk, consistent with a dose–response relationship. The protective effect of CRF on HF risk warrants further evaluation.
A centurial development of the North Sea fish megafauna as reflected by the historical Swedish longlining fisheries
Authors: Cardinale M , Bartolino V , Svedäng H , Sundelöf A , Poulsen R T , Casini M
Published: February 2014

Historically, to compensate for declining catches, fishers have usually shifted from species characterized by high catch rate onto less easily caught species or have moved into new fishing grounds. Such shifts are poorly documented for areas with a long history of exploitation (i.e. North Sea) as they occurred long time before the start of the regular assessments of the marine resources. The Swedish longline fisheries in the Kattegat‐Skagerrak and North Sea have a long history that spans over several centuries. These fisheries have historically targeted large demersal predator fish as ling (Molva molva), cod (Gadus morhua), Atlantic halibut (Hippoglossus hippoglossus) and skates (mainly Dipturus spp.). In this study, data from the Swedish longline fisheries from 1859 to 1960 have been collated. The data show that the geographical expansion of the fishery was extensive. At the turn of the 20th century, offshore longlining became concentrated north and west of the Shetlands and Hebrides, and after the WWII, the fishery expanded to Iceland and Rockall. In the offshore fishery, CPUE for the main target species, ling, remained stable, whereas for the other species, with the exception of tusk (Brosme brosme), CPUE showed a dramatic decline over time. In contrast, in the coastal longlining fishery, severe declines were revealed for all major target species except cod. We argue that the constant search for new fishing grounds in the Northeast Atlantic reflects a dwindling resource, where the fishermen kept the catch rates of ling high by travelling to more and more distant fishing grounds.
Human steroid and oxysterol 7α‐hydroxylase CYP7B1: substrate specificity, azole binding and misfolding of clinically relevant mutants
Authors: Yantsevich Aleksei V. , Dichenko Yaroslav V. , MacKenzie Farrell , Mukha Dmitry V. , Baranovsky Alexander V. , Gilep Andrei A. , Usanov Sergey A. , Strushkevich Natallia V.
Published: February 2014

Oxysterols and neurosteroids are important signaling molecules produced by monooxygenases of the cytochrome P450 family that realize their effect through nuclear receptors. CYP7B1 catalyzes the 6‐ or 7‐hydroxylation of both steroids and oxysterols and thus is involved in the metabolism of neurosteroids and bile acid synthesis, respectively. The dual physiological role of CYP7B1 is evidenced from different diseases, liver failure and progressive neuropathy, caused by enzyme malfunction. Here we present biochemical characterization of CYP7B1 at the molecular level to understand substrate specificity and susceptibility to azole drugs. Based on our experiments with purified enzyme, the requirements for CYP7B1 hydroxylation of steroid molecules are as follows: C5 hydrogen in the α‐configuration (or double bond at C5), a polar group at C17, a hydroxyl group at C3, and the absence of the hydroxyl group at C20–C24 in the C27‐sterol side chain. 21‐hydroxy‐pregnenolone was identified as a new substrate, and overall low activity toward pregnanes could be related to the increased potency of 7‐hydroxy derivatives produced by CYP7B1. Metabolic conversion (deactivation) of oxysterols by CYP7B1 in a reconstituted system proceeds via two sequential hydroxylations. Two mutations that are found in patients with diseases, Gly57Arg and Phe216Ser, result in apo‐P450 (devoid of heme) protein formation. Our CYP7B1 homology model provides a rationale for understanding clinical mutations and relatively broad substrate specificity for steroid hydroxylase.
Mechanical Properties of Canine Patella‐Ligament‐Tibia Segment
Authors: Biskup Jeffery , Freeman Andy , Camisa Will , Innes John , Conzemius Michael
Published: February 2014

Objective

To test the ex vivo mechanical properties of canine patella‐ligament‐tibia (PLT) segment and establish the relationship between donor size and PLT dimensions to the mechanical properties of PLT grafts.

Study Design

Ex vivo mechanical testing study.

Sample Population

Canine PLT segments (n = 21 dogs; 42 PLT).

Methods

Morphometric measurements of PLT segments were taken from computed tomography (CT) images and compared with results obtained using calipers. PLT were tested to failure at a rate of 100% length/s. Mechanical properties and failure mode were recorded.

Results

PLT width and thickness (P < .001 for both) measured by calipers were significantly lower than those taken from CT images. Thirty‐five (83%) specimens failed by avulsion fracture from the patella, 1 failed mid‐ligament, and 6 failed by tibial fracture. Dog weight and PLT length had the strongest Pearson's r value when correlated with load at failure (r = 0.73, 0.81, respectively).

Conclusion

Dog weight and PLT length were the best predictors of load at failure. PLT failure load of dogs weighing >25 kg were similar to those reported for the cranial cruciate ligament (CCL) suggesting that the PLT may be a suitable allograft for CCL replacement.
Surgical Technique and Short‐Term Outcome for Experimental Laparoscopic Closure of the Epiploic Foramen in 6 Horses
Authors: Munsterman Amelia S. , Hanson Russell Reid , Cattley Russell C. , Barrett Elizabeth J. , Albanese Valeria
Published: February 2014

Objective

To describe a laparoscopic technique for, and short‐term outcome after, closure of the epiploic foramen (EF) in horses.

Study Design

Descriptive, experimental study.

Animals

Healthy, adult horses (n = 6).

Methods

Laparoscopic portals to approach the EF were identified in standing horses. Under laparoscopic observation, the gastropancreatic fold and right lobe of the pancreas were grasped with Babcock forceps and secured to the caudate hepatic lobe using helical titanium coils to obliterate the EF. Surgical procedure time and intra‐ and postoperative complications were recorded. Serial analysis of select serum enzymes was used as an indication of involvement of the pancreas and liver. Closure was reevaluated at 4 weeks using repeat laparoscopy, and necropsy was performed immediately after.

Results

At initial surgery, EF closure was successful in all 6 horses; median surgical time was 40.5 minutes (range, 22–110 minutes). Serum gamma‐glutamyl transferase (GGT) and sorbitol dehydrogenase (SDH) were not significantly altered by the surgical procedure; however, aspartate aminotransferase (AST) and amylase (AMY) were transiently increased. At repeat laparoscopic reevaluation, closure was complete in 5 horses, with partial closure of the EF observed in 1 horse. No complications related to the procedure were noted during or after surgery in any horse.

Conclusions

EF closure in the standing horse can be accomplished without complications to the surrounding organs and vessels.
Photosynthetic performance of two poplar species in shelterbelt under water‐saving irrigation in arid northwest China
Authors: Zhu Cheng‐Gang , Chen Ya‐Ning , Li Wie‐Hong , Yang Yu‐Hai
Published: February 2014

Understanding the physiology of plants in arid regions under changed water availability is critical to projecting the future of arid ecosystems. A water‐saving irrigation has been implemented in an ecological shelter forest of an agricultural reclamation area located in the arid desert region in northwestern Dzungaria Basin in Xinjiang, China. In order to understand the effects of changed irrigation on trees, two poplar species (Populus euphratica and P. russkii) growing in the shelterbelt were selected, and their photosynthetic performance was contrasted by measuring their photosynthetic gas exchange and photochemical parameters under water‐saving irrigation and traditional extensive flood irrigation. Results showed that reduced water availability during water‐saving irrigation had a moderate but not significant impact on the photosynthesis of the two poplar species. Populus russkii was more sensitive to changed irrigation than P. euphratica, and the latter showed a relatively higher water‐deficit resistance and a better photosynthetic performance under water‐saving irrigation. Populus russkii exhibited higher capability of non‐photochemical quenching by thermal dissipation of excess excitation energy at both irrigation modes making it capable of maintaining excess energy better than P. euphratica. Thermal dissipation on excess energy and increased photo‐respiration rate at water‐saving irrigation together provided photo protection in P. euphratica. Both species can maintain normal function of the photosystem at water‐saving irrigation. The declined photosynthetic performance of the two species at water‐saving irrigation could be attributed to photo protection but not to photo inhibition. All this together suggested that the water‐saving irrigation implemented by a manager on the shelterbelt could be feasible.
Nutrient Management and the Chesapeake Bay
Authors: Beegle Douglas
Published: February 2014

The Chesapeake Bay is the largest estuary in the United States with a very large and diverse watershed. The health of the Bay related to pollution from nutrients and sediment has been in decline for many years. Agriculture in the watershed is one of the major contributors of nutrient and sediment pollution to the Chesapeake. The cause of the nutrient pollution from agriculture has usually been thought to have been the result of mismanagement of nutrients on farms. Consequently, the approaches to solving the problem have focused almost exclusively on changing farm management. As a result, significant progress has been made in improving on‐farm nutrient management but the health of the Bay remains a concern. An analysis of the structure of animal agriculture in the Bay watershed reveals that the problem is much deeper than simply mismanagement on farms. A major underlying cause is a regional nutrient imbalance resulting from an economically driven system of animal production based on importing from outside the watershed a large amount of the animal feed. Therefore, a long‐term, sustainable solution will require much more than just changing on‐farm management. To really solve this problem will require a restructuring of the animal production systems to internalize the environmental costs of this structural imbalance of nutrients in the watershed. The challenge that must be met is how to accomplish this in a way that is sustainable.
Fertilizer Use in Regulated River Basins: Is it What We Think?
Authors: Osmond Deanna L. , Neas Kathy , Johnson Amy M. , Cahill Sheri L.
Published: February 2014

Like many impacted coastal water systems, the Tar‐Pamlico River Basin and Jordan Lake watershed in North Carolina have had environmental rules implemented to reduce nitrogen and phosphorus loadings to their waters. Agriculture's contribution to nutrient loading in both basins was based on models, and no agricultural data were collected before rules were designed. A one‐time statistically valid area‐frame sampling was applied to agricultural fields in each of the basins to collect agricultural information, including fertilizer rates. This sampling was much more detailed than current USDA surveys. In both basins, nitrogen fertilizer rates were frequently lower than the recommended rates, and therefore, calculated nitrogen losses were lower than expected; phosphorus application rates were irrespective of soil test information. Generally, the survey found that producers in both basins are often under‐applying fertilizer, especially nitrogen, and minimizing environmental impact of nutrient and soil losses from agricultural fields through appropriate cropping systems and conservation practices.
Climate Change Mitigation Policies: Implications for Agriculture and Water Resources
Authors: Frisvold George B. , Konyar Kazim
Published: February 2014

This study examines how the proposed American Clean Energy and Security Act (H.R. 2454) would affect U.S. agriculture with special reference to water resources. The bill's cap and trade provisions for greenhouse gases would significantly raise fertilizer, irrigation pumping, and other energy‐related costs. By 2030, it would reduce U.S. irrigation water use by >11 percent and fertilizer use by >18 percent with positive implications for water conservation and quality. Carbon offset provisions create financial incentives for farmers to sequester carbon by planting trees on cropland, reducing agricultural production and raising prices. Because sequestration potential differs by region, most of the estimated 51 million acres of converted cropland would be in the Corn Belt and Mississippi Delta. Afforestation would reduce Delta water use further, but increase water use in other regions compared to cap and trade alone. Compared to a no‐policy baseline, irrigation water use declines 10 percent nationally, but increases in the Southern Plains. H.R. 2454 may have significant water conservation effects in some regions, but increase competition for water in others. By reducing fertilizer use and dramatically altering land use patterns in parts of the Mississippi Basin, it may also provide unexpected water quality benefits. Unintended water use and quality consequences of climate policies merit further research.
Farm and Ecological Resilience to Water Supply Variability
Authors: Schuster Elizabeth , Colby Bonnie
Published: February 2014

Water supplies are constrained in the lower Colorado River Basin in the western United States and northern Mexico by extensive agricultural use, increasing urban populations, ecosystem needs, and the pressures of climate change. Agriculture is the largest consumptive use of water, and better understanding of how farmers are managing water supply risk and adapting to unreliable water supplies can help lead to the creation of appropriate solutions for the region. Based upon original primary data collected in 2012 in the Mexicali Valley of northern Mexico, we present findings on farm households that give us a better understanding of agricultural water management and adaptation options. We build upon these results to present voluntary, market‐based solutions to improve the region's ability to adapt to water supply variability. Increasing use of water markets and improving the cooperation among stakeholders are promising solutions with the potential to benefit agricultural and ecological water interests alike.
Acequias and the Effects of Climate Change
Authors: Rango Albert , Fernald Alexander , Steele Caitriana , Hurd Brian , Ochoa Carlos
Published: February 2014

Traditional forms of acequia irrigation can be combined with ground based and remote sensing snow measurements and snowmelt runoff modeling to better estimate runoff volumes now and in the future under conditions of climate change. The experience gained over 400 years of irrigating small fields strongly binds communities and strengthens the resolve of acequia associations to contest challenges presented by climate change. Increased density of snow measurements in high elevations of the Rio Grande along with input of real‐time data to snowmelt models has led to an improved potential for acequia decision making under the increased temperatures projected for the future by climate models. Acequia communities and similar Native American settlements have shown the willingness to share water during times of severe water shortages in the southwestern U.S. Acequia associations have shown the desire to adopt new forms of hydrologic data and modeling techniques and incorporate them into acequia association approaches.
Water Requirements for Large‐Scale Solar Energy Projects in the West
Authors: Frisvold George B. , Marquez Tatiana
Published: February 2014

This study estimates how much water would be required to meet Renewable Portfolio Standards for electricity generation in five western states if 100 percent of this demand were supplied by solar power. Future renewable electricity demand (net of current supplies) is estimated for 2025 and 2035. One scenario assumes the most water‐intensive solar thermal technology supplies all this future demand. Although not a feasible scenario, the assumed water intensity (1057 gallons/MWh) provides an upper‐bound estimate of solar power water consumption that may be compared with regional water balances. A second scenario assumes the water intensity of future projects is comparable to the average of solar projects actually being deployed. Water intensity for these 34 projects with 8.7 GW of capacity averages 228 gallons/MWh – a lower rate than many conventional electricity facilities (i.e., coal, natural gas, nuclear). Water requirements by 2035 would be 0.8 percent of regional consumptive use of water under the upper bound scenario and 0.2 percent of consumptive use based on current, average water intensities.
Capturing LiDAR‐Derived Hydrologic Spatial Parameters to Evaluate Playa Wetlands
Authors: Tang Zhenghong , Li Ruopu , Li Xu , Jiang Weiguo , Hirsh Aaron
Published: February 2014

The digital elevation model data from traditional stereo photogrammetric methods are inadequate in providing accurate vertical parameters to feed hydrologic models for low‐lying, extremely flat areas. High‐resolution light detection and ranging (LiDAR) data provide the robust capability of capturing small variations in low‐relief playa wetlands. The Rainwater Basin in south‐central Nebraska includes a complex of seasonally shallow playa wetlands that attract millions of migratory waterfowl every spring and fall. This research focuses on the development of a procedure with applicable protocols to produce LiDAR‐derived three‐dimensional wetland maps and to extract the critical surface parameters (i.e., watershed boundaries, flow direction, flow accumulation, and drainage lines) for playa wetlands. The topo‐hydrologic conditions of playa wetlands were evaluated at the watershed level. The results show that in the Rainwater Basin, 70.7% of the historic hydric soil footprints identified in the Soil Survey Geographic (SSURGO) database were not functioning as topographically depressional wetlands. This finding was confirmed by a recent five‐year Annual Habit Survey showing that 69.8% of the historic hydric soil footprints did not function during the spring migratory bird seasons between 2004 and 2009. The majority of playa wetlands' topographic conditions have been substantially changed and theSSURGOdata cannot fully reflect current topographic reality in the Rainwater Basin.
Hydrological Variability and Uncertainty of Lower Missouri River Basin Under Changing Climate
Authors: Qiao Lei , Pan Zaitao , Herrmann Robert B. , Hong Yang
Published: February 2014

The lower Missouri River Basin has experienced increasing streamflow and flooding events, with higher risk of extreme hydrologic impacts under changing climate. The newly available North American Regional Climate Change Assessment Program (NARCCAP) climate projections were used as atmospheric forcing for Soil and Water Assessment Tool (SWAT) model which runs with varying potential evapotranspiration (PET) methods to assess the hydrological change and uncertainty of 2040‐2069 over 1968‐1997. The NARCCAP temperature and precipitation predictions were refined using a bias correction method. The results show that, following the seasonal variability of precipitation, various water fluxes would increase in most seasons except the summer. Expected precipitation tends to increase in intensity with little change in frequency, triggering faster surface water concentration to form floods. The greatest streamflow increase would occur from November to February, increasing by around 10% on average. An increase of 3% occurs in the other months except for July and August in which river discharge decreases by around 2%. The climate predictions contribute more uncertainty annually, but PET algorithms gain more influence in winter or when other weather factors such as wind play a relatively more important role on evapotranspiration flux. This study predicts an even wetter environment compared to the historically very wet period, with the possibility of more flooding.
Arc StormSurge: Integrating Hurricane Storm Surge Modeling and GIS
Authors: Ferreira Celso M. , Olivera Francisco , Irish Jennifer L.
Published: February 2014

Arc StormSurge is a data model that integrates geographic information systems and the hurricane wave and surge model SWAN+ADCIRC, which is the coupling of the Simulating WAves Nearshore (SWAN) wave model and the Advanced Circulation (ADCIRC) hydrodynamic model. The Arc StormSurge data model is a geodatabase, which is a relational database that can contain georeferenced information. It includes feature classes in feature datasets and tables, all related among them through relationship classes, and raster catalogs and grids. In addition to the data model schema, Arc StormSurge includes a number of pre‐ and post‐processing tools that help integrate spatial data and numerical modeling. As an illustration, Arc StormSurge was used to support the modeling of Hurricane Bret, which made landfall in the Corpus Christi area in Texas in 1999. By using Arc StormSurge, it was possible to take advantage of already available geo‐referenced information (e.g., base maps, land cover datasets, and monitoring station locations) for the model setup, and for identifying spatial patterns in the model results by presenting them in map format.
Sex identification and PIT‐tagging: tools and prospects for studying intersexual differences in freshwater fishes
Authors: Hulthén K. , Chapman B. B. , Nilsson P. A. , Hansson L.‐A. , Skov C. , Baktoft H. , Brodersen J. , Brönmark C.
Published: February 2014

This study evaluated a technique to allow the long‐term monitoring of individual fishes of known sex in the wild using sex confirmation in close proximity to the reproductive period combined with individual tagging. Hundreds of partially migratory roach Rutilus rutilus were tagged with passive integrated transponders (PIT) following sex determination in spring and various performance measures were compared with fish tagged outside the reproductive period in autumn. Short‐term survival was >95% for R. rutilus sexed and tagged under natural field conditions. Total length (LT) did not affect the probability of survival within the size range tagged (119–280 mm), nor were there differences in timing of migration the following season between individuals sexed and tagged in spring and individuals tagged in autumn (i.e. outside the reproductive period). Also, a similar per cent of R. rutilus sexed and tagged in spring and tagged in autumn migrated the following season (34·5 and 34·7%). Moreover, long‐term recapture data revealed no significant differences in body condition between R. rutilus individuals sexed and tagged in spring, individuals tagged in autumn and unmanipulated individuals. The observed sex ratio of recaptured fish did not differ from the expected values of equal recapture rates between males and females. Hence, there is no observable evidence for an adverse effect of tagging close to the reproductive period and therefore this method is suitable for studying intersexual differences and other phenotypic traits temporarily expressed during reproduction at the individual level in fishes.
Redescription of Chlorophthalmus corniger, a senior synonym of Chlorophthalmus bicornis (Family: Chlorophthalmidae)
Authors: Bineesh K. K. , Akhilesh K. V. , Gomon M. F. , Abdussamad E. M. , Pillai N. G. K. , Gopalakrishnan A.
Published: February 2014

Chlorophthalmus corniger is redescribed on the basis of recently collected specimens. The species is redefined as a species of Chlorophthalmus with the lower jaw terminating in a distinctly projecting horizontal plate with strong, spine‐like processes directed forward from the plate's corners; body silvery grey, with numerous minute black spots and traces of broad darker crossbars; base of anterior dorsal fin spines and distal parts of dorsal fins black; adipose fin tiny with numerous black spots; caudal fin black; 3·5 scales above lateral line; three rows of cheek scales; head very large, 34·3–40·1% standard length (LS); eye large, 29·8–40·8% head length (LH); pectoral fin long, extending to beyond dorsal fin base, 21·7–26·2% LS. Chlorophthalmus bicornis is a junior synonym of C. corniger based on the examination of the type series of both species. It is confined to the northern half of the Indian Ocean, reliably recorded from Somalia and the Gulf of Aden to southern Java, Indonesia, at depths between 200 and 500 m. A lectotype and three paralectotypes were designated for C. corniger. DNA barcodes for Indian species of Chlorophthalmus were generated.
Long‐term survival rate of teeth receiving multidisciplinary endodontic, periodontal and prosthodontic treatments
Authors: Moghaddam A. S. , Radafshar G. , Taramsari M. , Darabi F.
Published: February 2014

Deciding whether to replace or preserve a compromised tooth, even with emerging trends in implant dentistry, is still a common dilemma for practitioners. This study sought to determine the 3‐ to more than 10‐year survival rate of teeth that had undergone endodontic, periodontal and prosthodontic treatments. A total of 245 teeth in 87 patients were clinically and radiographically evaluated. All the teeth had received crown lengthening surgery by a single periodontist. Root canal therapy and prosthodontic procedures were rendered either by specialists or by experienced general dentists. Numbers of lost teeth were recorded and the criteria for hopeless teeth were defined. Survival rate was determined using the Kaplan–Meier estimator. Clinical indices including pocket depth (PD), bleeding index (BI), C/R ratio, position of the restoration margin relative to the gingival margin (RM‐GM) and the presence of intra‐canal post were compared between different survival groups (<3, 3–5, 5–10 and >10 years) using one‐way analysis of variance (anova). Potential predictors of failure were determined using the Cox regression model. The mean ± s.d. of 3‐, 5‐, 10‐ and 13‐year survival rates was 98 ± 1%, 96 ± 1·6%, 83·1 ± 4·5% and 51·9 ± 14·5%, respectively. The mean PD (P < 0·013), as well as C/R ratio in the mesial (P = 0·003) and distal (P = 0·007) surfaces, was significantly higher in the >10‐year‐survived teeth. Bleeding index and RM‐GM showed no significant differences between the groups. C/R ratio and RM‐GM position appeared to be the major determinants of tooth loss. The long‐term survival rate of multidisciplinary‐treated teeth was 83–98% in this specific sample.