bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract PL01-03: Epigenetics, aging, and cancer: From DNA methylation to microRNAs
Authors: Esteller Manel
Published: May 2012

An altered pattern of epigenetic modifications is central to many common human diseases, including cancer. Many studies have explored the mosaic patterns of DNA methylation and histone modifications in cancer cells on a gene-by-gene basis, among them the seminal finding of transcriptional silencing of tumor suppressor genes by CpG island promoter hypermethylation. Epigenetic gene inactivation in transformed cells involves many “belts of silencing”. We are in the process of completing the molecular dissection of the entire epigenetic machinery involved in methylation-associated silencing, such as DNA methyltransferases, methyl-CpG binding domain proteins, histone deacetylases, histone methyltransferases, histone demethylases and Polycomb proteins. The first indications are also starting to emerge about how the combination of cellular selection and targeted pathways leads to abnormal DNA methylation. In addition to classical tumorsuppressor and DNA repair genes, epigenetic gene silencing includes genes involved in premature aging and microRNAs with growth inhibitory functions. Recent technological advances are now enabling cancer epigenetics to be studied genome-wide. It is time to “upgrade” cancer epigenetics research and put together an ambitious plan to tackle the many unanswered questions in this field using genomics approaches to unravel the epigenome.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PL01-03.
Abstract PL03-02: Public health genomics: A scientific foundation for using genetic information in cancer prevention
Authors: Khoury Muin J.
Published: May 2012

With the accelerating pace of discoveries of human genetic variation, and molecular, biochemical, and cellular technologies for cancer care and prevention, there is an urgent need to develop population-level research, policy and practice processes to translate basic science discoveries into actions that reduce the population burden of cancer in the United States. The emerging scientific translation needs in the genomics era are substantial. Clinical and population sciences are now urgently needed to assess the distribution of genetic variants and their products biomarkers, and interactions with other genes and environmental factors. New methods are needed to assess the contribution of genes and gene-environment interactions (behavior, nutrition, chemicals, and other exposures) to individual and population risks for various cancers. Behavioral and social sciences are needed to assess how genetic information can be used to effect behavior change to reduce the burden of cancer. As importantly, delivery research on clinical utility, effectiveness, and economics of genomics-based health care applications are needed to assess their added value in cancer care and prevention. Genomics and related fields will also affect surveillance, dissemination and diffusion research as well as evaluation of cancer progression and survivorship. Without the expansion of clinical and population sciences in genomics, the promise of genome research and discoveries may not reach its full potential in the genomics era.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PL03-02.
Abstract PL04-03: Folate and cancer: Is timing everything?
Authors: Ulrich Cornelia M.
Published: May 2012

Folate is an essential B vitamin utilized for one-carbon transfer reactions, including those related to the methylation of DNA and nucleotide synthesis. Epidemiologic and experimental studies show that a low-folate status is associated with an increased risk of colorectal neoplasia. However, the actions of folate in cancer prevention appear to be modulated by both genetic susceptibility and timing with respect to carcinogenic progression. Functional polymorphisms in genes encoding several key enzymes in folate metabolism have been linked to cancer risk and exemplify the importance of nutrigenetic interactions in this biologic pathway. Yet, perhaps more importantly, the timing of folate administration during carcinogenesis may also impact the outcome and result in opposing effects: A higher folate status is expected to protect against mutations and, thus, may reduce the progression from normal tissue to pre-malignant lesions; however, a higher folate status may subsequently enhance the growth of pre-malignant lesions or any existing tumors, due to the supporting role of folate in the provision of nucleotides for DNA synthesis. Data from clinical trials suggest potential increases in risk of colorectal polyps and prostate cancer in folic acid intervention arms. Mathematical models from our group suggest that supplementation early in life could be beneficial, but adversely affect cancer rates later in life. These influences appear predominantly driven by effects on thymidylate synthesis. Because at this point available data are incomplete, prior to making recommendations, investigation is needed of the effects of folate supplementation among cancer patients, who are at risk of recurrence, as well as among individuals with cancer precursors.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PL04-03.
Abstract PR-06: Upregulation of microRNA-21 (miR-21) in human bronchial epithelial cells chronically exposed to 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) plus nicotine and modulation of these effects by diindolylmethane
Authors: Kassie Fekadu , Jarcho Michael , Endalew Abaineh
Published: May 2012

MicroRNAs (miRNAs) represent a class of naturally occurring small noncoding RNA molecules that regulate genes by either inducing mRNA degradation or inhibiting translation. The expression of miRNAs is deregulated in several cancers, including lung cancer. However, most studies have been carried out using full-blown cancer tissues and the regulation of miRNAs during early-stage tumorigenesis is unknown. In the present study, we used an in vitro model of lung tumorigenesis to assess the effect of chronic treatment with tobacco compounds on the expression of miR-21, one of the most deregulated miRNAs in lung cancer, in human bronchial epithelial cells (HBEC). Freshly prepared NNK (10 µM) and nicotine (10 µM) were added to the culture media containing NHBC every 3 days for 3 weeks. Beginning the second week of NNK plus nicotine treatment, the dietary chemopreventive agent diindolylmethane (DIM) was added, every 3 days, to the culture media until the termination of the study. Then, the cells were harvested, RNA prepared and the expression level of miR-21 and its target genes PDCD4 and RECK were analyzed by QRT-PCR. Levels of PDCD4 and RECK were also examined by Western immunoblotting. NNK plus nicotine treatment significantly elevated miR-21 levels but markedly decreased expression of PDCD4 and RECK at both gene and protein levels. The effect of the tobacco compounds on miR-21 as well PDCD4 and RECK was reversed by treatment with DIM. This study shows that miR-21 levels are deregulated beginning the early phase of lung tumorigenesis and miR-21 is a valuable target for chemopreventive agents.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PR-06.
Abstract PR-09: Genetic variations in the sonic hedgehog pathway and clinical outcomes in bladder cancer
Authors: Chen Meng , Kamat Ashish , Hildebrandt Michelle A.T. , Zhang Xiaofan , Grossman H. Barton , Dinney Colin P. , Wu Xifeng
Published: May 2012

The sonic hedgehog (Shh) pathway plays an important role in embryonic development and stem cell maintenance. Abnormal activation of Shh pathway has been implicated in the development of various cancers, and also in the progression to metastatic disease. We hypothesized that genetic variations in the Shh pathway may affect bladder cancer (BC) patients' clinical outcomes. We evaluated the association of 151 SNPs in nine Shh genes in a follow-up study of 738 bladder cancer patients for recurrence and progression risk in superficial BC patients, and survival in muscle-invasive and metastasis (MiM) BC patients. In superficial BC patients, GLI2 variants rs11685068 (HR: 2.12, 95% CI: 1.44–3.12) and rs7605011 (HR:1.94, 95% CI: 1.33–2.85) were significantly associated with higher recurrence risk. Individuals with rs11685068 (median survival time (MST): 7.3 months, Log-Rank P: 0.004) and rs7605011 (MST: 7.6 months, Log-Rank P: 0.002) variant alleles had shorter recurrence-free median survival time compared to patients with wild-type genotypes (MST: 16.7 months). In the subgroup receiving Bacillus Calmette-Guérin treatment, GLI3 variants rs6463089 (HR: 2.30, 95% CI: 1.44–3.66) and rs3801192 (HR: 2.57, 95% CI: 1.48–4.46) were significantly associated with higher recurrence risk and shorter recurrence-free survival durations. We also explored the cumulative effect of multiple SNPs and higher-order gene-gene interactions in modulating the recurrence. No significant associations were observed in the progression and survival analysis after correcting for multiple testing. This is the first study to evaluate the role of germline genetic variations in Shh pathway as predictors of bladder cancer outcomes. These findings warrant further replication in independent populations to identify BC patients at a high risk for a poor outcome and prognosis.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PR-09.
Abstract PR-10: The association of neighborhood socioeconomic context and mortality in a large national cohort in the United States: The NIHA-ARP Diet and Health Study
Authors: Doubeni Chyke , Laiyemo Adeyinka O. , Lian Min , Park Yikyung , Schootman Mario , Schatzkin Arthur
Published: May 2012

Background: Although several studies have reported that persons from lower socioeconomic groups have poorer health outcomes, few prospective studies have examined whether neighborhood socioeconomic context is associated with mortality. In this study, we prospectively evaluated whether persons residing in socioeconomically deprived neighborhoods have higher mortality risk compared to more resourced neighborhoods among a large geographically dispersed cohort.

Methods: Between 1995 and 1996, the NIH-AARP Diet and Health Study recruited an ethnically diverse prospective cohort of 566,402 persons, 50–71 years of age, from six U.S. states and two metropolitan areas. Detailed data were collected on diet, lifestyle, and medical history through questionnaires. Neighborhood socioeconomic information was obtained through linkage to the 2000 U.S. Census data at the tract level. We excluded 705 subjects with incomplete information for geocoding and computed an empirically derived index of neighborhood socioeconomic deprivation using principal component analyses. Mortality was ascertained through December 31, 2006. Two-level continuous-time survival models were used to derive hazard ratios of time to death from any cause stratified by gender.

Results: Of the 565,697 eligible subjects at baseline, the mean age was 62 years, 60% were male, 91% were non-Hispanic whites, 4% non-Hispanic blacks and 9% reported a history of cancer. A higher percentage of those in the most deprived neighborhoods reported poorer general health, higher average BMI, and lower Mediterranean diet scores. In multilevel Cox models analyses controlling for dietary and lifestyle factors, the risk of death increased with increasing levels of deprivation in the neighborhood of residence. Compared to the least deprived neighborhood, those residing in areas in the highest quintile of deprivation had a higher risk for death (men: hazard ratio [HR]: 1.22, 95% confidence interval [CI]: 1.18–1.25); women: HR: 1.23, 95% CI: 1.17–1.29).

Conclusion: Our study suggests that living in socioeconomically deprived neighborhoods is associated with a higher risk for death independent of lifestyle and dietary risk factors.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PR-10.
Hypertension Control Among Patients Followed by Cardiologists
Authors: Navar-Boggan Ann Marie , Boggan Joel C. , Stafford Judith A. , Muhlbaier Lawrence H. , McCarver Catherine , Peterson Eric D.
Published: May 2012

Background—

Hypertension control is an important and modifiable risk factor for cardiovascular disease. The overall rate of hypertension control among patients followed in cardiology clinics, as well as clinician variability in control rates, is unknown.

Methods and Results—

We conducted a retrospective cohort study of patients with hypertension (n=5979) routinely followed in a cardiology clinic (n=47 physicians). Overall, 30.3% of patients with hypertension had suboptimal control (blood pressure [BP] ≥140/90 mm Hg) at the end of a 13-month follow-up period. Patient-level factors associated with control were younger age, male sex, white ethnicity, having a primary care provider at Duke, private insurance, Medicare/Medicaid, and comorbid diagnoses of heart failure or coronary artery disease. Unadjusted rates of suboptimal BP control among clinicians' clinic patient panels ranged from 16% to 44%. Even after adjusting for patient factors, patients' odds of BP control varied 6-fold, depending on their treating clinician. Using a patient's average BP rather than their most recent BP did not result in significant changes in provider performance. In chart reviews (n=300), clinicians failed to document a plan to address hypertension in 38% of patients with elevated BP in the clinic.

Conclusions—

Up to one-third of patients followed routinely by cardiologists in clinic have suboptimally controlled BP, with wide variability in performance across individual clinicians. This variability, alongside evidence that elevated BP is often not acted on during clinic visits, demonstrates a potential opportunity for quality improvement.
Essential Role of Bone Marrow for Microvascular Endothelial and Metabolic Functions in Mice
Authors: Nakajima Sota , Ohashi Junko , Sawada Ayuko , Noda Kazuki , Fukumoto Yoshihiro , Shimokawa Hiroaki
Published: May 2012

Rationale:

We have previously demonstrated that the importance of endothelium-derived hyperpolarizing factor (EDHF) increases as the vessel size decreases and that endothelium-derived hydrogen peroxide (H
2
O
2
) is an EDHF in animals and humans, for which endothelial nitric oxide synthase (eNOS) is the major source. Recent studies have suggested the important role of the bone marrow (BM) in modulating cardiovascular and metabolic functions.

Objective:

We aimed to examine whether BM plays a role in modulating microvascular endothelial and metabolic functions in mice, and if so, to elucidate the mechanisms involved.

Methods and Results:

Male eNOS
−/−
mice were transplanted with BM cells from wild-type (WT) or eNOS
−/−
mice and were maintained for 6 weeks. Endothelium-dependent relaxations and hyperpolarizations of mesenteric arteries to acetylcholine were reduced in eNOS
−/−
mice and were markedly improved when transplanted with WT-BM but not with eNOS
−/−
-BM. The enhanced component of endothelium-dependent relaxations was abolished by catalase, indicating that the improved responses were mediated by H
2
O
2
. In contrast, no such beneficial effect was noted in the aorta. Reduced plasma adiponectin levels and impaired glucose tolerance in eNOS
−/−
mice were also improved by WT-BM transplantation. Neuronal nitric oxide synthase (nNOS) in mesenteric arteries of eNOS
−/−
mice was significantly upregulated only when transplanted with WT-BM. Importantly, the beneficial effects of WT-BM transplantation were absent in eNOS
−/−
/adiponectin
−/−
or eNOS
−/−
/nNOS
−/−
mice.

Conclusions:

These results provide the first evidence that BM plays an important role in modulating microvascular endothelial and metabolic functions, for which adiponectin and nNOS may be involved.
Impact of the Presence and Extent of Incomplete Angiographic Revascularization After Percutaneous Coronary Intervention in Acute Coronary Syndromes
Authors: Rosner Gregg F. , Kirtane Ajay J. , Genereux Philippe , Lansky Alexandra J. , Cristea Ecaterina , Gersh Bernard J. , Weisz Giora , Parise Helen , Fahy Martin , Mehran Roxana , Stone Gregg W.
Published: May 2012

Background—

The clinical significance of incomplete coronary revascularization (ICR) after percutaneous coronary intervention in patients with acute coronary syndromes is unknown.

Methods and Results—

We performed quantitative angiography of the entire coronary tree in 2954 patients with acute coronary syndromes in the Acute Catheterization and Urgent Intervention Triage Strategy (ACUITY) trial. ICR was variably defined if any lesion with diameter stenosis (DS) cutoffs ranging from ≥30% to ≥70% with reference vessel diameter ≥2.0 mm remained after percutaneous coronary intervention. The primary outcome was 1-year composite rate of major adverse cardiac events (death, myocardial infarction, or ischemia-driven unplanned revascularization). With the use of DS cutoffs ≥30%, ≥40%, ≥50%, ≥60%, and ≥70%, the prevalence of ICR after percutaneous coronary intervention was 75%, 55%, 37%, 25%, and 17%, respectively. The 1-year major adverse cardiac event rate was increased among patients with ICR using all of the DS cutoffs. ICR (≥50% DS) was associated with higher 1-year rates of myocardial infarction (12.0% versus 8.2%; hazard ratio, 1.50; 95% confidence interval, 1.18–1.89;
P
=0.0007) and ischemia-driven unplanned revascularization (15.7% versus 10.2%; hazard ratio, 1.58; 95% confidence interval, 1.28–1.96;
P
<0.0001), with a trend toward increased mortality (3.1% versus 2.2%; hazard ratio, 1.43; 95% confidence interval, 0.90–2.27;
P
=0.13). By multivariable analysis, ICR (≥50% DS) was an independent predictor of 1-year major adverse cardiac events (hazard ratio, 1.36; 95% confidence interval, 1.12–1.64;
P
=0.002). The impact of ICR on major adverse cardiac events was similar regardless of chronic total occlusion presence, but it was more pronounced with a greater number of nonrevascularized lesions.

Conclusions—

Depending on the threshold of percent DS, ICR was present in 17% to 75% of patients with acute coronary syndromes after percutaneous coronary intervention. Regardless of the threshold, ICR was strongly associated with 1-year myocardial infarction, ischemia-driven unplanned revascularization, and major adverse cardiac events.

Clinical Trial Registration—

URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT00093158.
Human Genome-Wide Association and Mouse Knockout Approaches Identify Platelet Supervillin as an Inhibitor of Thrombus Formation Under Shear Stress
Authors: Edelstein Leonard C. , Luna Elizabeth J. , Gibson Ian B. , Bray Molly , Jin Ying , Kondkar Altaf , Nagalla Srikanth , Hadjout-Rabi Nacima , Smith Tara C. , Covarrubias Daniel , Jones Stephen N. , Ahmad Firdos , Stolla Moritz , Kong Xianguo , Fang Zhiyou , Bergmeier Wolfgang , Shaw Chad , Leal Suzanne M. , Bray Paul F.
Published: May 2012

Background—

High shear force critically regulates platelet adhesion and thrombus formation during ischemic vascular events. To identify genetic factors that influence platelet thrombus formation under high shear stress, we performed a genome-wide association study and confirmatory experiments in human and animal platelets.

Methods and Results—

Closure times in the shear-dependent platelet function analyzer (PFA)–100 were measured on healthy, nondiabetic European Americans (n=125) and blacks (n=116). A genome-wide association (
P
<5×10
−8
) was identified with 2 single-nucleotide polymorphisms within the
SVIL
gene (chromosome 10p11.23) in African Americans but not European Americans. Microarray analyses of human platelet RNA demonstrated the presence of
SVIL
isoform 1 (supervillin) but not muscle-specific isoforms 2 and 3 (archvillin, SmAV).
SVIL
mRNA levels were associated with
SVIL
genotypes (
P
≤0.02) and were inversely correlated with PFA-100 closure times (
P
<0.04) and platelet volume (
P
<0.02). Leukocyte-depleted platelets contained abundant levels of the ≈205-kDa supervillin polypeptide. To assess functionality, mice lacking platelet supervillin were generated and back-crossed onto a C57BL/6 background. Compared with controls, murine platelets lacking supervillin were larger by flow cytometry and confocal microscopy and exhibited enhanced platelet thrombus formation under high-shear but not low-shear conditions.

Conclusions—

We show for the first time that (1) platelets contain supervillin; (2) platelet thrombus formation in the PFA-100 is associated with human
SVIL
variants and low
SVIL
expression; and (3) murine platelets lacking supervillin exhibit enhanced platelet thrombus formation at high shear stress. These data are consistent with an inhibitory role for supervillin in platelet adhesion and arterial thrombosis.
Carotid Endarterectomy in Asymptomatic Patients With Limited Life Expectancy
Authors: Wallaert Jessica B. , De Martino Randall R. , Finlayson Samuel R.G. , Walsh Daniel B. , Corriere Matthew A. , Stone David H. , Cronenwett Jack L. , Goodney Philip P.
Published: May 2012

Background and Purpose

Data from randomized trials assert that asymptomatic patients undergoing carotid endarterectomy (CEA) must live 3 to 5 years to realize the benefit of surgery. We examined how commonly CEA is performed among asymptomatic patients with limited life expectancy.

Methods

Within the American College of Surgeons National Quality Improvement Project we identified 8 conditions associated with limited life expectancy based on survival estimates using external sources. We then compared rates of 30-day stroke, death, and myocardial infarction after CEA between asymptomatic patients with and without life-limiting conditions.

Results

Of 12 631 CEAs performed in asymptomatic patients, 2525 (20.0%) were in patients with life-limiting conditions or diagnoses. The most common conditions were severe chronic obstructive pulmonary disease and American Society of Anesthesiologists Class IV designation. Patients with life-limiting conditions had significantly higher rates of perioperative complications, including stroke (1.8% versus 0.9%,
P
<0.001), death (1.4% versus 0.3%,
P
<0.001), and stroke/death (2.9% versus 1.1%,
P
<0.001). Even after adjustment for other comorbidities, patients with life-limiting conditions were nearly 3 times more likely to experience perioperative stroke or death than those without these conditions (OR, 2.8; 95% CI, 2.1–3.8;
P
<0.001).

Conclusion

CEA is performed commonly in asymptomatic patients with life-limiting conditions. Given the high rates of postoperative stroke/death in these patients as well as their limited life expectancy, the net benefit of CEA in this population remains uncertain. Health policy research examining the role of CEA in asymptomatic patients with life-limiting conditions is necessary and may serve as a potential source for significant healthcare savings in the future.
The Course of Unilateral Intracranial Arteriopathy in Young Adults With Arterial Ischemic Stroke
Authors: Bulder Marcel M.M. , Braun Kees P.J. , Leeuwis Jan Willem , Lo Rob T.H. , van Nieuwenhuizen Onno , Kappelle L. Jaap , Klijn Catharina J.M.
Published: May 2012

Background and Purpose—

Unilateral intracranial focal nonprogressive arteriopathy is often found in children with arterial ischemic stroke. We aimed to investigate the course of unilateral intracranial arteriopathy in young adults.

Methods—

We searched the Utrecht Stroke Database for patients between 16 and 50 years of age diagnosed with anterior circulation arterial ischemic stroke and a nonatherosclerotic, unilateral intracranial large-artery arteriopathy between 1991 and 2005. We assessed clinical features, potential causes, risk factors, extent of infarction and arteriopathy at presentation, long-term angiographic course, and clinical outcome.

Results—

Of 356 patients with anterior circulation arterial ischemic stroke, 17 (5%) had a documented unilateral intracranial arteriopathy, of whom 14 could be included for follow-up investigations (median age, 34 years; range, 27–49 years). Median duration of follow-up was 8.8 years (range, 1.7–12.8 years). In 11 patients, onset of symptoms was not abrupt. The arteriopathy normalized completely in 5 and improved in 3 patients; in none of the patients did the arteriopathy worsen. Two of 14 patients had recurrent symptoms. Ten patients (71%) had a good outcome (modified Rankin Scale score ≤2).

Conclusions—

In young adults, arterial ischemic stroke is rarely caused by a unilateral intracranial arteriopathy. Similar to children, onset of symptoms in young adults is often not abrupt and the arteriopathy may improve over time. Late recurrences were rare. Possibly, a monophasic inflammatory process, as has been suggested for childhood intracranial focal nonprogressive arteriopathies, also occurs in young adults.
Fruit Carts: A Domain and Corpus for Research in Dialogue Systems and Psycholinguistics
Authors: Aist Gregory , Campana Ellen , Allen James , Swift Mary , Tanenhaus Michael K.
Published: May 2012

We describe a novel domain, Fruit Carts, aimed at eliciting human language production for the twin purposes of (a) dialogue system research and development and (b) psycholinguistic research. Fruit Carts contains five tasks: choosing a cart, placing it on a map, painting the cart, rotating the cart, and filling the cart with fruit. Fruit Carts has been used for research in psycholinguistics and in dialogue systems. Based on these experiences, we discuss how well the Fruit Carts domain meets four desired features: unscripted, context-constrained, controllable difficulty, and separability into semi-independent subdialogues. We describe the domain in sufficient detail to allow others to replicate it; researchers interested in using the corpora themselves are encouraged to contact the authors directly.
Stakeholders’ perceptions of abuse of children with disabilities at a special school in Zimbabwe
Authors: Musengi Martin , Shumba Almon
Published: May 2012

The study sought to determine: (a) the perceptions of students with disabilities, their teachers, caregivers and parents about what constitutes child abuse of children with disabilities; and (b) how these stakeholders view the school’s efforts to help children with disabilities avoid abuse and cope with instances of abuse. A purposive sample of 14 children with various disabilities, 7 teachers who taught and counselled these children and 2 caregivers who looked after the children in their hostels at the residential school participated in this study. Seven parents of children with disabilities were also interviewed. Data were analysed using themes in this study. Teachers, parents and caregivers reported that young girls with disabilities were forced into sexual relations by older boys and men. Children with visual and hearing impairments reported that corporal punishment was administered on them; and embarrassing name-calling and verbal abuse by some teachers and caregivers as behaviour modification strategies.
The Inclusion of Children in Family Dispute Resolution in Australia: Balancing Welfare versus Rights Principles
Authors: Henry Pamela , Hamilton Karine
Published: May 2012

Over the course of the 2000s, Australia has been at the international forefront of implementing child-inclusive services to families undergoing separation (Birnbaum, 2009). Around the world, various policy initiatives and research projects have suggested that the direct participation of children in family separation processes correctly recognises the child’s right to be heard in matters of direct relevance to them. This article reports on the findings of a study which involved the interviewing of children and parents participating in family separation mediation in Australia. The key findings were that for most children their inclusion in the mediation was either unremarkable or beneficial in some important ways, however in a small number of cases involving family violence and/or anger, their inclusion sparked fear in children. We conclude that child inclusive separation processes must recognize the pervasiveness of family violence and balance the right of children to be heard with traditional welfare principles regarding the protection of children.
The Radiation Budget of the West African Sahel and Its Controls: A Perspective from Observations and Global Climate Models
Authors: Miller Mark A. , Ghate Virendra P. , Zahn Robert K.
Published: May 2012

Continuous measurements of the shortwave (SW), longwave (LW), and net cross-atmosphere radiation flux divergence over the West African Sahel were made during the year 2006 using the Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF) and the Geostationary Earth Radiation Budget (GERB) satellite. Accompanying AMF measurements enabled calculations of the LW, SW, and net top of the atmosphere (TOA) and surface cloud radiative forcing (CRF), which quantifies the radiative effects of cloud cover on the column boundaries. Calculations of the LW, SW, and net cloud radiative effect (CRE), which is the difference between the TOA and surface radiative flux divergences in all-sky and clear-sky conditions, quantify the radiative effects on the column itself. These measurements were compared to predictions in four global climate models (GCMs) used in the Intergovernmental Panel for Climate Change Fourth Assessment Report (IPCC AR4). All four GCMs produced wet and dry seasons, but reproducing the SW column radiative flux divergence was problematic in the GCMs and SW discrepancies translated into discrepancies in the net radiative flux divergence. Computing cloud-related quantities from the measurements produced yearly averages of the SW TOA CRF, surface CRF, and CRE of ~−19, −83, and 47 W m−2, respectively, and yearly averages of the LW TOA CRF, surface CRF, and CRE of ~39, 37, and 2 W m−2. These quantities were analyzed in two GCMs and compensating errors in the SW and LW clear-sky, cross-atmosphere radiative flux divergence were found to conspire to produce somewhat reasonable predictions of the net clear-sky divergence. Both GCMs underestimated the surface LW and SW CRF and predicted near-zero SW CRE when the measured values were substantially larger (~70 W m−2 maximum).
A Climatology of Subtropical Cyclones in the South Atlantic
Authors: Evans Jenni L. , Braun Aviva
Published: May 2012

A 50-yr climatology (1957–2007) of subtropical cyclones (STs) in the South Atlantic is developed and analyzed. A subtropical cyclone is a hybrid structure (upper-level cold core and lower-level warm core) with associated surface gale-force winds. The tendency for warm season development of North Atlantic STs has resulted in these systems being confused as tropical cyclones (TCs). In fact, North Atlantic STs are a regular source of the incipient vortices leading to North Atlantic TC genesis. In 2004, Hurricane Catarina developed in the South Atlantic and made landfall in Brazil. A TC system had been previously unobserved in the South Atlantic, so the incidence of Catarina highlighted the lack of an ST climatology for the region to provide a context for the likelihood of future systems.

Sixty-three South Atlantic STs are documented over the 50-yr period analyzed in this climatology. In contrast to the North Atlantic, South Atlantic STs occur relatively uniformly throughout the year; however, their preferred location of genesis and mechanisms for this genesis do exhibit some seasonal variability. Rossby wave breaking was identified as the mechanism for the ST vortex initiation for North Atlantic STs. A subset of South Atlantic STs forms via this mechanism, however, an additional mechanism for ST genesis is identified here: lee cyclogenesis downstream of the Andes in the Brazil Current region—an area favorable for convection. This formation mechanism is similar to development of type-2 east coast lows in the Tasman Sea off eastern Australia.
The Influence of Boundary Layer Processes on the Diurnal Variation of the Climatological Near-Surface Wind Speed Probability Distribution over Land*
Authors: He Yanping , McFarlane Norman A. , Monahan Adam H.
Published: May 2012

Knowledge of the diurnally varying land surface wind speed probability distribution is essential for surface flux estimation and wind power management. Global observations indicate that the surface wind speed probability density function (PDF) is characterized by a Weibull-like PDF during the day and a nighttime PDF with considerably greater skewness. Consideration of long-term tower observations at Cabauw, the Netherlands, indicates that this nighttime skewness is a shallow feature connected to the formation of a stably stratified nocturnal boundary layer. The observed diurnally varying vertical structure of the leading three climatological moments of near-surface wind speed (mean, standard deviation, and skewness) and the wind power density at the Cabauw site can be successfully simulated using the single-column version of the Canadian Centre for Climate Modelling and Analysis (CCCma) fourth-generation atmospheric general circulation model (CanAM4) with a new semiempirical diagnostic turbulent kinetic energy (TKE) scheme representing downgradient turbulent transfer processes for cloud-free conditions. This model also includes a simple stochastic representation of intermittent turbulence at the boundary layer inversion. It is found that the mean and the standard deviation of wind speed are most influenced by large-scale “weather” variability, while the shape of the PDF is influenced by the intermittent mixing process. This effect is quantitatively dependent on the asymptotic flux Richardson number, which determines the Prandtl number in stable flows. High vertical resolution near the land surface is also necessary for realistic simulation of the observed fine vertical structure of wind speed distribution.
Atlantic Warm-Pool Variability in the IPCC AR4 CGCM Simulations
Authors: Liu Hailong , Wang Chunzai , Lee Sang-Ki , Enfield David
Published: May 2012

This study investigates Atlantic warm pool (AWP) variability in the twentieth century and preindustrial simulations of coupled GCMs submitted to the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4). In the twentieth-century simulations, most coupled models show very weak AWP variability, represented by an AWP area index, because of the cold SST bias in the AWP. Among the IPCC models, a higher AWP SST index corresponds to increased net downward shortwave radiation and decreased low-level cloud fraction during the AWP peak season. This suggests that the cold SST bias in the AWP region is at least partly caused by an excessive amount of simulated low-level cloud, which blocks shortwave radiation from reaching the sea surface. AWP natural variability is examined in preindustrial simulations. Spectral analysis reveals that only multidecadal band variability of the AWP is significant in observations. All models successfully capture the multidecadal band, but they show that interannual and/or decadal variability is also significant. On the multidecadal time scale, the global SST difference pattern between large AWP years and small AWP years resembles the geographic pattern of the AMO for most coupled models. Observational analysis indicates that both positive ENSO phase and negative NAO phase in winter correspond to reduced trade winds in the AWP region. The westerly anomalies induced by positive ENSO and negative NAO lead to local heating and warm SST from March to May and February to April, respectively. This behavior as a known feature of anomalous AWP growth is well captured by only five models.
Greenland Freshwater Runoff. Part I: A Runoff Routing Model for Glaciated and Nonglaciated Landscapes (HydroFlow)
Authors: Liston Glen E. , Mernild Sebastian H.
Published: May 2012

A gridded linear-reservoir runoff routing model (HydroFlow) was developed to simulate the linkages between runoff production from land-based snowmelt and icemelt processes and the associated freshwater fluxes to downstream areas and surrounding oceans. HydroFlow was specifically designed to account for glacier, ice sheet, and snow-free and snow-covered land applications. Its performance was verified for a test area in southeast Greenland that contains the Mittivakkat Glacier, the local glacier in Greenland with the longest observed time series of mass-balance and ice-front fluctuations. The time evolution of spatially distributed gridcell runoffs required by HydroFlow were provided by the SnowModel snow-evolution modeling system, driven with observed atmospheric data, for the years 2003 through 2010. The spatial and seasonal variations in HydroFlow hydrographs show substantial correlations when compared with observed discharge coming from the Mittivakkat Glacier area and draining into the adjacent ocean. As part of its discharge simulations, HydroFlow creates a flow network that links the individual grid cells that make up the simulation domain. The collection of networks that drain to the ocean produced a range of runoff values that varied most strongly according to catchment size and percentage and elevational distribution of glacier cover within each individual catchment. For 2003–10, the average annual Mittivakkat Glacier region runoff period was 200 ± 20 days, with a significant increase in annual runoff over the 8-yr study period, both in terms of the number of days (30 days) and in volume (54.9 × 106 m3).
CALIPSO-Derived Three-Dimensional Structure of Aerosol over the Atlantic Basin and Adjacent Continents
Authors: Adams Aaron M. , Prospero Joseph M. , Zhang Chidong
Published: May 2012

Accurate modeling of the impact of aerosols on climate requires a detailed understanding of the vertical distribution of aerosols. The Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) provides continuous high-resolution vertical profiles of aerosol properties on a near-global scale. Here the CALIPSO Vertical Feature Mask is used to document the three-dimensional (3D) frequency-of-occurrence distribution of aerosols over a broad region of the Atlantic Ocean, Africa, Europe, and the Americas. The 3D distributions illustrate the seasonal cycle in the zonal and meridional variability of the vertical profiles of mineral dust, biomass-burning smoke, polluted dust (external mixture of dust and smoke), and polluted continental aerosol, and also of their emissions sources and transport pathways. Four aerosol domains stand out in the product: dust over North Africa and the Middle East and smoke over southern Africa and South America. The transport pathways of African dust and smoke over the Atlantic are evident. The intertropical convergence zone (ITCZ) plays a clear role in limiting the southward transport of North African dust and northward transport of South African smoke. Dust and smoke are mixed in the ITCZ and consequently the highest probability of polluted dust is found there, even though the probabilities of dust and smoke in this region are relatively low. The mixing of dust and pollution has significant implications for cloud microphysical processes over a broad region of the Atlantic.
The Reliability of Antarctic Tropospheric Pressure and Temperature in the Latest Global Reanalyses
Authors: Bracegirdle Thomas J. , Marshall Gareth J.
Published: May 2012

In this study, surface and radiosonde data from staffed Antarctic observation stations are compared to output from five reanalyses [Climate Forecast System Reanalysis (CFSR), 40-yr ECMWF Re-Analysis (ERA-40), ECMWF Interim Re-Analysis (ERA-Interim), Japanese 25-year Reanalysis (JRA-25), and Modern Era Retrospective-Analysis for Research and Applications (MERRA)] over three decades spanning 1979–2008. Bias and year-to-year correlation between the reanalyses and observations are assessed for four variables: mean sea level pressure (MSLP), near-surface air temperature (Ts), 500-hPa geopotential height (H500), and 500-hPa temperature (T500).

It was found that CFSR and MERRA are of a sufficiently high resolution for the height of the orography to be accurately reproduced at coastal observation stations. Progressively larger negative Ts biases at these coastal stations are apparent for reanalyses in order of decreasing resolution. However, orography height bias cannot explain large winter warm biases in CFSR, JRA-25, and MERRA (11.1°, 10.2°, and 7.9°C, respectively) at Amundsen–Scott and Vostok, which have been linked to problems with representing the surface energy balance.

Linear trends in the annual-mean T500 and H500 averaged over Antarctica as a whole were found to be most reliable in CFSR, ERA-Interim, and MERRA, none of which show significant trends over the period 1979–2008. In contrast JRA-25 shows significant negative trends over 1979–2008 and ERA-40 gives significant positive trends during the 1980s (evident in both T500 and H500). Comparison to observations indicates that the positive trend in ERA-40 is spurious. At the smaller spatial scale of individual stations all five reanalyses have some spurious trends. However, ERA-Interim was found to be the most reliable for MSLP and H500 trends at station locations.
An Enhanced Influence of Tropical Indian Ocean on the South Asia High after the Late 1970s
Authors: Qu Xia , Huang Gang
Published: May 2012

The tropical Indian Ocean (TIO)’s influence on the South Asia high (SAH)’s intensity experiences a decadal change in the late 1970s; after (before) the decadal shift, the influence is significant (insignificant). The present study investigates the role of tropospheric temperature in relaying the impact of sea surface temperature (SST) to the SAH and the change in the TIO’s influence. During the two epochs, the local tropospheric temperature responses to the TIO warming are distinct—more significant during the second epoch. It is inferred that this change may be responsible for the strengthening of the TIO’s influence on the SAH. Encouragingly, the ensemble simulations accurately capture the time of the decadal change, indicating that the enhanced influence is attributed to the SST forcing.

There are two possible reasons for the change in the TIO–SAH relationship. The first reason is the change in the locations of the SST anomalies in the TIO. During the second epoch, positive SST anomalies lie in the Indian Ocean warm pool. Through the background vigorous convection and moist adjustment, the SST anomalies affect largely the tropospheric temperature and thus the SAH. The second reason is the decadal change in mean SST and the SST variability. During the recent decades, both the background SST and the variability of the TIO SST increase, which enhance the influence of the SST anomalies on the atmosphere. The influence of the remote oceanic forcing on the enhanced TIO–SAH relationship and its comparison with the contribution of the TIO SST are also discussed.
What Drives the Variability of Evaporative Demand across the Conterminous United States?
Authors: Hobbins Michael , Wood Andrew , Streubel David , Werner Kevin
Published: May 2012

To understand the sources of temporal and spatial variability of atmospheric evaporative demand across the conterminous United States (CONUS), a mean-value, second-moment uncertainty analysis is applied to a spatially distributed dataset of daily synthetic pan evaporation for 1980–2009. This evaporative demand measure is from the “PenPan” model, which is a combination equation calibrated to mimic observations from U.S. class-A evaporation pans and here driven by six North American Land Data Assimilation System variables: temperature, specific humidity, station pressure, wind speed, and downwelling shortwave and longwave radiation. The variability of evaporative demand is decomposed across various time scales into contributions from these drivers. Contrary to popular expectation and much hydrologic practice, temperature is not always the most significant driver of temporal variability in evaporative demand, particularly at subannual time scales. Instead, depending on the season, one of four drivers (temperature, specific humidity, downwelling shortwave radiation, and wind speed) dominates across different regions of CONUS. Temperature generally dominates in the northern continental interior. This analysis assists land surface modelers in balancing parameter parsimony and physical representativeness. Patterns of dominant drivers are shown to cycle seasonally, with clear implications for modeling evaporative demand in operational hydrology or as a metric of climate change and variability. Depending on the region and season, temperature, specific humidity, downwelling shortwave radiation, and wind speed must together be examined, with downwelling longwave radiation as a secondary input. If any variable may be ignored, it is atmospheric pressure. Parameterizations of evaporative demand based solely on temperature should be avoided at all time scales.
Surface Skin Temperature and the Interplay between Sensible and Ground Heat Fluxes over Arid Regions
Authors: Zeng Xubin , Wang Zhuo , Wang Aihui
Published: May 2012

Over arid regions, two community land models [Noah and Community Land Model (CLM)] still have difficulty in realistically simulating the diurnal cycle of surface skin temperature. Based on theoretical arguments and synthesis of previous observational and modeling efforts, three revisions are developed here to address this issue. The revision of the coefficients in computing roughness length for heat significantly reduces the underestimate of daytime skin temperature but has a negligible effect on nighttime skin temperature. The constraints of the minimum friction velocity and soil thermal conductivity help improve nighttime skin temperature under weak wind and dry soil conditions. These results are robust in both Noah and CLM, as well as in Noah, with 4 versus 10 soil layers based on in situ data at the Desert Rock site in Nevada with a monthly averaged diurnal amplitude of 31.7 K and the Gaize site over Tibet, China, with an amplitude of 44.6 K. While these revisions can be directly applied to CLM or other land models with subgrid tiles (including bare soil), suggestions are also made on their application to Noah and other land models that treat bare soil and vegetated area together in a model grid cell. It is suggested that the challenging issue of measuring and simulating surface sensible heat flux under stable conditions should be treated as a land–atmosphere coupled issue, involving the interplay of ground and sensible heat fluxes in balancing the net radiation over arid regions, rather than as an atmospheric turbulence issue alone. The implications of such a coupling perspective are also discussed.
Toward a Framework for Systematic Error Modeling of Spaceborne Precipitation Radar with NOAA/NSSL Ground Radar–Based National Mosaic QPE
Authors: Kirstetter Pierre-Emmanuel , Hong Y. , Gourley J. J. , Chen S. , Flamig Z. , Zhang J. , Schwaller M. , Petersen W. , Amitai E.
Published: May 2012

Characterization of the error associated with satellite rainfall estimates is a necessary component of deterministic and probabilistic frameworks involving spaceborne passive and active microwave measurements for applications ranging from water budget studies to forecasting natural hazards related to extreme rainfall events. The authors focus here on the error structure of NASA’s Tropical Rainfall Measurement Mission (TRMM) Precipitation Radar (PR) quantitative precipitation estimation (QPE) at ground. The problem is addressed by comparison of PR QPEs with reference values derived from ground-based measurements using NOAA/NSSL ground radar–based National Mosaic and QPE system (NMQ/Q2). A preliminary investigation of this subject has been carried out at the PR estimation scale (instantaneous and 5 km) using a 3-month data sample in the southern part of the United States. The primary contribution of this study is the presentation of the detailed steps required to derive a trustworthy reference rainfall dataset from Q2 at the PR pixel resolution. It relies on a bias correction and a radar quality index, both of which provide a basis to filter out the less trustworthy Q2 values. Several aspects of PR errors are revealed and quantified including sensitivity to the processing steps with the reference rainfall, comparisons of rainfall detectability and rainfall-rate distributions, spatial representativeness of error, and separation of systematic biases and random errors. The methodology and framework developed herein applies more generally to rainfall-rate estimates from other sensors on board low-earth-orbiting satellites such as microwave imagers and dual-wavelength radars such as with the Global Precipitation Measurement (GPM) mission.