bluuebunny/crossref_metadata_2025 huggingface dataset:
Hypoxia and Senescence: The Impact of Oxygenation on Tumor Suppression
Authors: Welford Scott M. , Giaccia Amato J.
Published: March 2011

Cellular senescence has emerged as a biological response to two major pathophysiological states of our being: cancer and aging. In the course of the transformation of a normal cell to a cancerous cell, senescence is frequently induced to suppress tumor development. In aged individuals, senescence is found in cells that have exhausted their replication potential. The similarity in these responses suggests that understanding how senescence is mediated can provide insight into both cancer and aging. One environmental factor that is implicated in both of these states is tissue hypoxia, which increases with aging and can inhibit senescence. Hypoxia is particularly important in normal physiology to maintain the stem cell niche; but at the same time, hypoxic inhibition of an essential tumor suppressor response can theoretically contribute to cancer initiation. Mol Cancer Res; 9(5); 538–44. ©2011 AACR.
Effects of Exercise Training on the Severity and Composition of Atherosclerotic Plaque in apoE-Deficient Mice
Authors: Kadoglou Nikolaos P.E. , Kostomitsopoulos Nikolaos , Kapelouzou Alkistis , Moustardas Petros , Katsimpoulas Michalis , Giagini Athina , Dede Eleni , Boudoulas Harisios , Konstantinides Stavros , Karayannacos Panayotis E. , Liapis Christos D.
Published: March 2011

Aim: To investigate the effects of exercise on atherosclerotic plaque composition, the concentration of matrix metalloproteinases (MMPs) in the atherosclerotic plaque and the systemic circulation. Methods: Ninety apolipoprotein E-deficient (apoE–/–) mice (45 male) were randomized to the following groups (n = 15 each): control male/female; sedentary male/female; exercise male/female. Mice were kept on a 16-week high-fat diet. Subsequently, the control groups were sacrificed, while the rest of the animals were placed on a normal diet for 6 more weeks. During the latter period, the exercise groups were trained daily on treadmill. At the end of the study, mice were euthanized, and blood samples as well as aortic root specimens were obtained. Results: Compared to control and sedentary animals, exercise training reduced atherosclerotic plaques (–30%; p < 0.01) and increased elastin and collagen content in both genders (p < 0.05). Body weight or lipid profile did not change significantly. Decreased macrophages and MMP-9 as well as increased tissue inhibitor of metalloproteinases 1 (TIMP-1) levels were observed in the atherosclerotic plaques of the exercise-treated groups (p < 0.05). Plasma concentrations of MMP-9 decreased, while plasma TIMP-1 levels increased in the exercise compared to control and sedentary groups (p < 0.05). Conclusions: Exercise training had a favorable effect on the size and composition of the atherosclerotic plaque in apoE–/– mice, associated with suppressed MMP activity.
The Long-Term Effects of Psychotherapy Added to Pharmacotherapy on Morning to Evening Diurnal Cortisol Patterns in Outpatients with Major Depression
Authors: Hsiao Fei-Hsiu , Jow Guey-Mei , Lai Yu-Ming , Chen Yu-Ting , Wang Kuo-Chang , Ng Siu-Man , Ho Rainbow T.H. , Chan Cecilia L.W. , Yang Tsung-Tsair
Published: March 2011

Background: Psychotherapy added to pharmacotherapy results in greater improvement in clinical outcomes than does pharmacotherapy alone. However, few studies examined how psychotherapy coupled with pharmacotherapy could produce a long-term protective effect by improving the psychobiological stress response. Methods: The researchers recruited 63 subjects with major depressive disorder (MDD) in an outpatient department of psychiatry at a general hospital. The randomly assigned subjects formed 2 groups: 29 in combined therapy (COMB) and 34 in monotherapy (MT). The COMB included 8 weekly body-mind-spirit group psychotherapy sessions added to pharmacotherapy. MT consisted of pharmacotherapy only. The outcome measures, collected at the subjects’ homes, included the Beck Depression Inventory II (BDI-II), the State Trait Anxiety Inventory (STAI) and salivary cortisol on awakening, 45 min after awakening, and at 12.00, 17.00 and 21.00 h. Evaluation of outcome measures was at baseline condition, and at months 2 (end of additional psychotherapy), 5 and 8. Results: While the decreases in symptoms of depression were similar between COMB and MT (p > 0.05), the reductions in anxiety state were greater in COMB than in MT during the 8-month follow-up (p < 0.05). A steeper diurnal cortisol pattern more likely occurred in COMB than in MT in the 3 follow-up periods (p < 0.05, p <0.001 and p < 0.01). Conclusions: The superior outcomes of group psychotherapy added to pharmacotherapy for MDD outpatients could relate to decreasing the anxiety state and to producing long-term impacts on positive stress endocrine outcomes seen as a steeper diurnal cortisol pattern.
Collision Tumor of Meningioma and Malignant Astrocytoma
Authors: Khalatbari Mahmoudreza , Borghei-Razavi Hamid , Shayanfar Nasrin , Behzadi Ashkan Heshmatzade , Sepehrnia Abolghassem
Published: March 2011

The authors report a 12-year-old boy who was presented with headache, nausea, vomiting and seizure. His magnetic resonance imaging showed 2 adjacent tumors in the region of the left ventricular trigone. The pathology of tumors reported collision tumors composed of meningioma and malignant astrocytoma.
Are Arachnoid Cysts Localized Hydrocephali?
Authors: Kim Tae-Gon , Kim Dong-Seok , Choi Joong-Uhn
Published: March 2011

We report 2 cases of arachnoid cysts related to a head trauma. The first case involved a 1-year-old girl who developed an arachnoid cyst 7 months after suffering a head trauma due to a motor vehicle accident, and the second case involved a 1-year-old boy whose arachnoid cyst was first noted 2 months subsequent to his premature birth. We present the serial imaging for both cases. Choi and Kim [Pediatr Neurosurg 1998;29:260–266] postulated that head trauma in infancy may contribute to the pathogenesis of arachnoid cysts in some cases. In presenting our cases, we support this hypothesis, and further postulate that the arachnoid cysts may in fact be localized hydrocephali, triggered either by head trauma or by prematurity.
Effectiveness of Systems Training for Emotional Predictability and Problem Solving (STEPPS) for Borderline Personality Problems in a ‘Real-World’ Sample: Moderation by Diagnosis or Severity?
Authors: Bos Elisabeth H. , van Wel E. Bas , Appelo Martin T. , Verbraak Marc J.P.M.
Published: March 2011

Background: Systems Training for Emotional Predictability and Problem Solving (STEPPS) is a group treatment for borderline personality disorder (BPD). Two prior randomized controlled trials (RCTs) have shown the efficacy of this training. In both RCTs, patients with borderline features who did not meet the DSM-IV criteria for BPD were excluded, which were many. We investigated the effectiveness of STEPPS in a sample representative of routine clinical practice and examined whether DSM-IV diagnosis and/or baseline severity were related to differential effectiveness. Methods: Patients whom their practicing clinician diagnosed with BPD were randomized to STEPPS plus adjunctive individual therapy (STEPPS, n = 84) or to treatment as usual (TAU, n = 84). Results: STEPPS recipients showed more improvement on measures of general and BPD-specific psychopathology as well as quality of life than TAU recipients, both at the end of treatment and at a 6-month follow-up. Presence of DSM-IV-diagnosed BPD was not related to differential treatment effectiveness, but dimensional measures of symptom severity were; STEPPS was superior to TAU particularly in patients with higher baseline severity scores. Conclusions: The findings show the effectiveness of STEPPS in a ‘real-world’ sample, and underscore the importance of dimensional versus categorical measures of personality disturbance.
Moyamoya Disease in Children with Congenital Dwarfing Conditions
Authors: Moftakhar Parham , Smith Edward R. , Choulakian Armen , Scott R. Michael , Danielpour Moise
Published: March 2011

Congenital dwarfisms can be associated with a variety of vascular anomalies. Here, we describe 2 patients with congenital dwarfisms who presented with moyamoya syndrome and underwent indirect intracranial revascularization. The pathogenesis of moyamoya syndrome in this population is not well understood, but it is a major cause of stroke and early death in these patients, making their timely diagnosis and management critical.
Medulloblastoma with Extensive Nodularity Undergoing Post-Therapeutic Maturation to a Gangliocytoma: A Case Report and Literature Review
Authors: Chelliah Daniel , Mensah Sarfo-Poku Christian , Stea Baldassarre D. , Gardetto Jennifer , Zumwalt Jonathan
Published: March 2011

We present a report of a 12-year-old boy diagnosed with medulloblastoma at 22 months of age. A gross total resection was performed followed by adjuvant systemic chemotherapy due to his young age; however, the tumor recurred locally in the posterior fossa 7 months later. The recurrent tumor was excised and he received craniospinal radiation with a boost given to the posterior fossa followed by high-dose chemotherapy. He remained disease free for approximately 10 years without major neurologic deficit and only mild cognitive impairment. A routine follow-up MRI of the brain revealed an enhancing mass. The patient underwent surgical debulking and pathological examination revealed no residual immature medulloblastoma cells but instead mature ganglion cells, consistent with a gangliocytoma. The apparent maturation of primitive medulloblastoma cells is a rare phenomenon, which may have ensued from the long-term effects of adjuvant therapies inducing advanced cellular maturation.
Pitx2c Modulates Cardiac-Specific Transcription Factors Networks in Differentiating Cardiomyocytes from Murine Embryonic Stem Cells
Authors: Lozano-Velasco Estefanía , Chinchilla Ana , Martínez-Fernández Sergio , Hernández-Torres Francisco , Navarro Francisco , Lyons Gary E. , Franco Diego , Aránega Amelia E.
Published: March 2011

Aim: The knowledge of the molecular signals that control cell differentiation into cardiomyocytes is critical to apply cell-based therapies and repair an injured heart. The transcription factor Pitx2 has essential roles in the development of different organs including the heart. Although a direct role of Pitx2 in the developing myocardium has recently been reported, the molecular pathways driven by Pitx2 as well as its cardiac target genes remain largely unexplored. The aim of this study was to unravel the molecular mechanisms driven by Pitx2 during the process of cardiomyocyte differentiation in vitro in mouse embryonic stem cell-derived cardiomyocytes. Methods and Results: Pitx2c was overexpressed in the R1-embryonic stem cell line. mRNA levels and protein distribution of several specific cardiac genes were analyzed by real-time PCR and immunohistochemistry experiments in R1-embryonic stem cell-derived beating areas at different stages of in vitro differentiation. Our results show that overexpression of Pitx2c in embryonic stem cell-derived cardiomyocytes is able to dynamically upregulate several cardiac-enriched transcription factors such as Isl1, Mef2c and Gata4. Additionally, Pitx2c induces the expression of chamber-specific cardiac genes such as Tbx5, Nppa and Cx40. These data were validated in an in vivo model of Pitx2 loss of function. Conclusion: Taken together, these results demonstrate that Pitx2 plays a major role reinforcing the transcriptional program of cardiac differentiation.
Matrix Metalloproteinase-9 Deficiency Results in Decreased Fiber Cross-Sectional Area and Alters Fiber Type Distribution in Mouse Hindlimb Skeletal Muscle
Authors: Mehan Ryan S. , Greybeck Bradley J. , Emmons Kayla , Byrnes William C. , Allen David L.
Published: March 2011

Matrix metalloproteinases (MMPs) play a major role in the degradation of the extracellular matrix (ECM) of skeletal muscle, and the inducible gelatinase MMP-9 in particular appears to be critical for the remodeling of muscle ECM during growth and repair. Here we determined the effects of MMP-9 gene inactivation on fiber type and size in the tibialis anterior (TA), gastrocnemius (GAST), and soleus (SOL) muscles in female mice. In the TA, the cross-sectional area (CSA) of the myosin heavy chain (MyHC) IIb-expressing fibers was significantly smaller in MMP-9 null mice while in the GAST, CSA of all three fast fiber types was decreased. In the SOL, MyHC type I-expressing fibers were significantly smaller in the MMP-9 null mice. The percentage of MyHC type IIb-expressing fibers was significantly increased in the TA and GAST of MMP-9 null mice, while the percentage of MyHC IId-expressing fibers significantly decreased in the GAST of MMP-9 null mice. Fiber percentages in the SOL were not significantly different between the two lines. Despite these changes in fiber size and type, in vivo hindlimb force production was not changed in MMP-9 null mice. Meanwhile, neither expression of the constitutive gelatinase MMP-2 nor immunohistochemical staining for type IV collagen was significantly altered by MMP-9 inactivation in any muscles examined. The present study demonstrates that MMP-9 inactivation results in changes in fiber size and type in adult mouse hindlimb muscles that may depend on indirect mechanisms involving reduced bone growth or nerve changes in response to MMP-9 inactivation.
Establishment and Characterization of Porcine Colonic Epithelial Cells Grown in Primary Culture
Authors: Petto Carola , Lesko Szilvia , Gäbel Gotthold , Böttner Martina , Wedel Thilo , Kacza Johannes , Pfannkuche Helga
Published: March 2011

Background: Primary cultures of epithelial cells are suitable models for studying epithelial function and, in particular, the regulation of epithelial tightness in vitro. The aim of our study was to develop a protocol for the isolation and culture of porcine colonic epithelial cells and to establish transepithelial electrical resistance (TEER) as a functional parameter for epithelial tightness. Methods: Epithelial cells were obtained from the proximal colon of piglets by enzymatic dispase digestion. Cells were cultured on collagen-coated membrane supports for 21 days. The epithelial origin of the cells was shown by immunohistochemical detection of cytokeratin and zonula occludens protein 1 (ZO-1). Scanning electron microscopy, transmission electron microscopy and confocal microscopy were used for further morphological characterization. The integrity and tightness of the artificial epithelium were determined by measuring TEER. Results: The cultured epithelial cells were immunoreactive for cytokeratin and ZO-1. They showed dense microvilli on their apical membranes and expression of Na+/K+-ATPase on their basolateral membranes. Adjacent cells were connected by tight junctions. We observed TEER to continuously increase up to 870 ± 38 Ω·cm2 during the culture period. TEER correlated with the amount of epithelial cells expressing ZO-1. Conclusions: The properties of primary cultured epithelial cells resemble the structural properties of polarized colonic epithelium in vivo. Measurement of TEER seems to be suitable for studying epithelial tightness in vitro. We suggest that these primary epithelial cultures be used to investigate the regulation of the epithelial barrier function.
Effects of Electrolytic Lesion of Medial Septum on Some Immune Responses in Rats
Authors: Dutta Goutam , Mondal Nilotpal , Goswami Anandaraj , Majumdar Durjoy , Ghosh Tusharkanti
Published: March 2011

Background/Aim: Considering the modulatory role of medial septum (MS) on behavioral and autonomic activities, and its neural connections with other brain areas having effects on the immune system, the role of MS on some immune responses has been investigated. Methods: Hyperreactivity scores, total count and differential count of WBC, phagocytic activity of blood WBC, leukocyte adhesive inhibition index (LAI), delayed type of hypersensitive (DTH) reaction and serum corticosterone (CORT) concentration were measured in MS-lesioned, sham-operated and control rats after 2 and 3 weeks of operation. The results of MS-lesioned rats were compared to those in the control and sham-operated rats. Results: The hyperreactivity score was not changed in the MS-lesioned rats. The phagocytic activity of blood WBC was increased but the DTH reaction and percentage of LAI were decreased in the MS-lesioned rats compared to the control and sham-operated rats 2 weeks after surgery. The serum CORT concentration was increased in the MS-lesioned rats compared to the control and sham-operated rats 2 weeks after surgery. After 3 weeks of MS lesion these immunological parameters and CORT concentration returned back to the normal values indicating a transient change of these parameters. Conclusion: This study concludes a complex and differential regulatory role of MS in the immune functions which are not linked with the hyperreactive behavior in rats. This immunoregulation of MS appears to be different from that of the lateral septum like their dissimilar modulatory roles in some behaviors.
Endogenous Secretory Receptor for Advanced Glycation End Products and Chronic Kidney Disease in the Elderly Population
Authors: Dalal Mansi , Semba Richard D. , Sun Kai , Crasto Candace , Varadhan Ravi , Bandinelli Stefania , Fink Jeffrey C. , Guralnik Jack M. , Ferrucci Luigi
Published: March 2011

Background/Aims: The relationship of circulating endogenous secretory receptor for advanced glycation end products (esRAGE) and chronic kidney disease (CKD) has not been well characterized. The aim of the study was to determine whether plasma esRAGE is associated with CKD and is predictive of developing CKD in older adults. Methods: The relationship between plasma esRAGE and CKD (more than stage 3 of the National Kidney Foundation classification; estimated glomerular filtration rate <60 ml/min/1.73 m2) and CKD over 6 years of follow-up was examined in a cross-sectional and prospective study design in 1,016 men and women, ≧65 years, in the InCHIANTI study, a population-based cohort study of aging in Tuscany, Italy. Results: At enrollment, 158 (15.5%) had CKD. Mean (SD) plasma esRAGE was 0.45 (0.24) ng/ml. Plasma esRAGE (ng/ml) was associated with CKD (odds ratio per 1 SD = 1.30; 95% CI 1.1–1.6; p < 0.005) in a multivariable logistic regression model, adjusting for potential confounders. Plasma esRAGE was an independent predictor of incident CKD over 6 years of follow-up (hazard ratio per 1 SD = 1.37; 95% CI 1.1–1.7; p < 0.008) in a multivariable Cox proportional hazards model, adjusting for potential confounders. Conclusions: Elevated plasma esRAGE is independently associated with CKD and is an independent predictor of incident CKD in older community-dwelling adults.
Effects of Anticholinergic Drugs on Cognitive Function in Older Australians: Results from the AIBL Study
Authors: Sittironnarit Gobhathai , Ames David , Bush Ashley I. , Faux Noel , Flicker Leon , Foster Jonathan , Hilmer Sarah , Lautenschlager Nicola T. , Maruff Paul , Masters Colin L. , Martins Ralph N. , Rowe Christopher , Szoeke Cassandra , Ellis Kathryn A. ,   AIBL research group
Published: March 2011

Background/Aims: The nature and extent of adverse cognitive effects due to the prescription of anticholinergic drugs in older people with and without dementia is unclear. Methods: We calculated the anticholinergic load (ACL) of medications taken by participants of the Australian Imaging, Biomarkers and Lifestyle (AIBL) study of ageing, a cohort of 211 Alzheimer’s disease (AD) patients, 133 mild cognitive impairment (MCI) patients and 768 healthy controls (HC) all aged over 60 years. The association between ACL and cognitive function was examined for each diagnostic group (HC, MCI, AD). Results: A high ACL within the HC group was associated with significantly slower response speeds for the Stroop color and incongruent trials. No other significant relationships between ACL and cognition were noted. Conclusion: In this large cohort, prescribed anticholinergic drugs appeared to have modest effects upon psychomotor speed and executive function, but not on other areas of cognition in healthy older adults.
Procedure-Type Risk Categories for Pediatric and Congenital Cardiac Catheterization
Authors: Bergersen Lisa , Gauvreau Kimberlee , Marshall Audrey , Kreutzer Jacqueline , Beekman Robert , Hirsch Russel , Foerster Susan , Balzer David , Vincent Julie , Hellenbrand William , Holzer Ralf , Cheatham John , Moore John , Lock James , Jenkins Kathy
Published: March 2011

Background—

The Congenital Cardiac Catheterization Project on Outcomes (C3PO) was established to develop outcome assessment methods for pediatric catheterization.

Methods and Results—

Six sites have been recording demographic, procedural and immediate outcome data on all cases, using a web-based system since February 2007. A sample of data was independently audited for validity and data completeness. In 2006, participants categorized 84 procedure types into 6 categories by anticipated risk of an adverse event (AE). Consensus and empirical methods were used to determine final procedure risk categories, based on the outcomes: any AE (level 1 to 5); AE level 3, 4, or 5; and death or life-threatening event (level 4 or 5). The final models were then evaluated for validity in a prospectively collected data set between May 2008 and December 31, 2009. Between February 2007 and April 2008, 3756 cases were recorded, 558 (14.9%) with any AE; 226 (6.0%) level 3, 4, or 5; and 73 (1.9%) level 4 or 5. General estimating equations models using 6 consensus-based risk categories were moderately predictive of AE occurrence (c-statistics: 0.644, 0.664, and 0.707). The participant panel made adjustments based on the collected empirical data supported by clinical judgment. These decisions yielded 4 procedure risk categories; the final models had improved discrimination, with c-statistics of 0.699, 0.725, and 0.765. Similar discrimination was observed in the performance data set (n=7043), with c-statistics of 0.672, 0.708, and 0.721.

Conclusions—

Procedure-type risk categories are associated with different complication rates in our data set and could be an important variable in risk adjustment models for pediatric catheterization.
Pharmacodynamic Effects of Different Aspirin Dosing Regimens in Type 2 Diabetes Mellitus Patients With Coronary Artery Disease
Authors: Capodanno Davide , Patel Aasita , Dharmashankar Kodlipet , Ferreiro José Luis , Ueno Masafumi , Kodali Murali , Tomasello Salvatore D. , Capranzano Piera , Seecheran Naveen , Darlington Andrew , Tello-Montoliu Antonio , Desai Bhaloo , Bass Theodore A. , Angiolillo Dominick J.
Published: March 2011

Background—

Patients with type 2 diabetes mellitus (T2DM) have reduced aspirin-induced pharmacodynamic effects. This may be attributed to increased platelet turnover rates resulting in an increased proportion of non–aspirin-inhibited platelets during the daily dosing interval. The hypothesis of this study was that an increase in the frequency of drug administration [twice daily (bid) versus once daily (od)] may provide more effective platelet inhibition in T2DM patients.

Methods and Results—

T2DM patients with stable coronary artery disease were prospectively recruited. Patients modified their aspirin regimen on a weekly basis according to the following scheme: 81 mg/od, 81 mg/bid, 162 mg/od, 162 mg/bid, and 325 mg/od. Pharmacodynamic assessments included light-transmittance aggregometry after arachidonic acid, collagen and adenosine diphosphate stimuli; VerifyNow-Aspirin assay; and serum thromboxane B
2
(TXB
2
) levels. Twenty patients were analyzed. All patients were sensitive and compliant to aspirin irrespective of dose, as assessed by arachidonic acid–induced aggregation. When aspirin was administered once daily, there was no significant effect on platelet reactivity by increasing the once-daily dosing using aspirin-sensitive assays (collagen-induced aggregation and VerifyNow-Aspirin). An increase in aspirin dose by means of a second daily administration was associated with a significant reduction in platelet reactivity assessed by collagen-induced aggregation and VerifyNow-Aspirin between 81 mg/od and 81 mg/bid (
P
<0.05 for both assays) and between 81 mg/od and 162 mg/bid (
P
<0.05 for both assays). There was no impact of aspirin dosing regimens on adenosine diphosphate–induced aggregation. A dose-dependent effect of aspirin was observed on serum TXB
2
levels (
P
=0.003).

Conclusions—

Aspirin dosing regimens are associated with different pharmacodynamic effects in platelets from T2DM patients and stable coronary artery disease, with a twice-daily, low-dose aspirin administration resulting in greater platelet inhibition than once-daily administration as assessed by aspirin-sensitive assays and a dose-dependent effect on serum TXB
2
levels. The clinical implications of a modified aspirin regimen tailored to T2DM patients warrant further investigation.

Clinical Trial Registration—

URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT01201785.
The Effectiveness of Ultrabrief and Brief Educational Videos for Training Lay Responders in Hands-Only Cardiopulmonary Resuscitation
Authors: Bobrow Bentley J. , Vadeboncoeur Tyler F. , Spaite Daniel W. , Potts Jerald , Denninghoff Kurt , Chikani Vatsal , Brazil Paula R. , Ramsey Bob , Abella Benjamin S.
Published: March 2011

Background—

Bystander cardiopulmonary resuscitation (CPR) improves survival from out-of-hospital cardiac arrest (OHCA) but often is not performed. We hypothesized that subjects viewing very short Hands-Only CPR videos will (1) be more likely to attempt CPR in a simulated OHCA scenario and (2) demonstrate better CPR skills than untrained individuals.

Methods and Results—

This study is a prospective trial of 336 adults without recent CPR training randomized into 4 groups: (1) control (no training) (n=51); (2) 60-second video training (n=95); (3) 5-minute video training (n=99); and (4) 8-minute video training, including manikin practice (n=91). All subjects were tested for their ability to perform CPR during an adult OHCA scenario using a CPR-sensing manikin and Laerdal PC SkillReporting software. One half of the trained subjects were randomly assigned to testing immediately and the other half after a 2-month delay. Twelve (23.5%) controls did not even attempt CPR, which was true of only 2 subjects (0.7%;
P
=0.01) from any of the experimental groups. All experimental groups had significantly higher average compression rates (closer to the recommended 100/min) than the control group (
P
<0.001), and all experimental groups had significantly greater average compression depth (>38 mm) than the control group (
P
<0.0001).

Conclusions—

Laypersons exposed to very short Hands-Only CPR videos are more likely to attempt CPR and show superior CPR skills than untrained laypersons.

Clinical Trial Registration—

URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT01191736.
West African Monsoon Dynamics and Eastern Equatorial Atlantic and Pacific SST Anomalies (1970–88)
Authors: Janicot Serge , Harzallah Ali , Fontaine Bernard , Moron Vincent
Published: March 2011

The Laboratoire de Météorologie Dynamique atmospheric GCM is used to investigate relationships between West African monsoon dynamics and SST anomalies in the eastern equatorial Atlantic and Pacific for the period 1970–88. Positive SST anomalies in the eastern equatorial Pacific, mainly associated with a larger east–west divergent circulation over the tropical Atlantic, are found to coincide with negative rainfall anomalies over West Africa. This is the case for the composite ENSO warm episodes of 1972, 1976, 1982, and 1983. By contrast, positive SST anomalies in the eastern equatorial Atlantic are accompanied by a southward shift of the intertropical convergence zone along with negative rainfall anomalies in the Sahel and positive rainfall anomalies in the Guinean region. This was the case in 1987. The ENSO warm event during this year had apparently no significant impact on West African monsoon dynamics. A zonal atmospheric coupling associated with differences of SST anomalies between the eastern equatorial Pacific and the Atlantic is evident in the period 1970–88. Positive (negative) phases of this coupling could enhance the impact of ENSO warm (cold) events on West African monsoon dynamics.
The Surface Radiation Budget over Oceans and Continents
Authors: Garratt J. R. , Prata A. J. , Rotstayn L. D. , McAvaney B. J. , Cusack S.
Published: March 2011

An updated evaluation of the surface radiation budget in climate models (1994–96 versions; seven datasets available, with and without aerosols) and in two new satellite-based global datasets (with aerosols) is presented. All nine datasets capture the broad mean monthly zonal variations in the flux components and in the net radiation, with maximum differences of some 100 W m−2 occurring in the downwelling fluxes at specific latitudes. Using long-term surface observations, both from land stations and the Pacific warm pool (with typical uncertainties in the annual values varying between ±5 and 20 W m−2), excess net radiation (RN) and downwelling shortwave flux density (So↓) are found in all datasets, consistent with results from earlier studies [for global land, excesses of 15%–20% (12 W m−2) in RN and about 12% (20 W m−2) in So↓]. For the nine datasets combined, the spread in annual fluxes is significant: for RN, it is 15 (50) W m−2 over global land (Pacific warm pool) in an observed annual mean of 65 (135) W m−2; for So↓, it is 25 (60) W m−2 over land (warm pool) in an annual mean of 176 (197) W m−2.

The effects of aerosols are included in three of the authors’ datasets, based on simple aerosol climatologies and assumptions regarding aerosol optical properties. They offer guidance on the broad impact of aerosols on climate, suggesting that the inclusion of aerosols in models would reduce the annual So↓ by 15–20 W m−2 over land and 5–10 W m−2 over the oceans. Model differences in cloud cover contribute to differences in So↓ between datasets; for global land, this is most clearly demonstrated through the effects of cloud cover on the surface shortwave cloud forcing. The tendency for most datasets to underestimate cloudiness, particularly over global land, and possibly to underestimate atmospheric water vapor absorption, probably contributes to the excess downwelling shortwave flux at the surface.
CAPE Variations in the Current Climate and in a Climate Change
Authors: Ye Bing , Del Genio Anthony D. , Lo Kenneth K-W.
Published: March 2011

Observed variations of convective available potential energy (CAPE) in the current climate provide one useful test of the performance of cumulus parameterizations used in general circulation models (GCMs). It is found that frequency distributions of tropical Pacific CAPE, as well as the dependence of CAPE on surface wet-bulb potential temperature (Θw) simulated by the Goddard Institute for Space Studies’s GCM, agree well with that observed during the Australian Monsoon Experiment period. CAPE variability in the current climate greatly overestimates climatic changes in basinwide CAPE in the tropical Pacific in response to a 2°C increase in sea surface temperature (SST) in the GCM because of the different physics involved. In the current climate, CAPE variations in space and time are dominated by regional changes in boundary layer temperature and moisture, which in turn are controlled by SST patterns and large-scale motions. Geographical thermodynamic structure variations in the middle and upper troposphere are smaller because of the canceling effects of adiabatic cooling and subsidence warming in the rising and sinking branches of the Walker and Hadley circulations. In a forced equilibrium global climate change, temperature change is fairly well constrained by the change in the moist adiabatic lapse rate and thus the upper troposphere warms to a greater extent than the surface. For this reason, climate change in CAPE is better predicted by assuming that relative humidity remains constant and that the temperature changes according to the moist adiabatic lapse rate change of a parcel with 80% relative humidity lifted from the surface. The moist adiabatic assumption is not symmetrically applicable to a warmer and colder climate: In a warmer regime moist convection determines the tropical temperature structure, but when the climate becomes colder the effect of moist convection diminishes and the large-scale dynamics and radiative processes become relatively important. Although a prediction based on the change in moist adiabat matches the GCM simulation of climate change averaged over the tropical Pacific basin, it does not match the simulation regionally because small changes in the general circulation change the local boundary layer relative humidity by 1%–2%. Thus, the prediction of regional climate change in CAPE is also dependent on subtle changes in the dynamics.
Means and Trends of Shortwave Irradiance at the Surface Estimated from Global Energy Balance Archive Data
Authors: Gilgen H. , Wild M. , Ohmura A.
Published: March 2011

Means and trends of shortwave irradiance at the earth’s surface are calculated from pyranometer measurements stored in the Global Energy Balance Archive (GEBA) database. The GEBA database contains the most comprehensive set of shortwave irradiance monthly means. The relative random error of measurement is approximately 5% of a monthly mean in general and approximately 2% of a yearly mean. The shortwave irradiance yearly means are analyzed in a 2.5° × 2.5° grid. In average example grid cells in Europe (no large altitude differences, no coasts), the difference of shortwave irradiance yearly means measured at different stations (station effect) is less than 5% of the cell mean, and the interannual variability is approximately 4% of the cell mean. On most continents, shortwave irradiance decreases significantly in large regions, and significant positive trends are observed only in four small regions.
The 1995 and 1996 North Atlantic Hurricane Seasons: A Return of the Tropical-Only Hurricane
Authors: Kimberlain Todd B. , Elsner James B.
Published: March 2011

Hurricane activity over the North Atlantic basin during 1995 and 1996 is compared to the combined hurricane activity over the previous four years (1991–94). The earlier period produced a total of 15 hurricanes compared to a total of 20 hurricanes over the latter period. Despite this similarity in numbers, the hurricanes of 1995 and 1996 were generally of the tropical-only variety, which marks a substantial departure from activity during the early 1990s. The return of tropical-only hurricanes to the Atlantic basin is likely the result of several global and local factors, including cool SST conditions in the equatorial central and eastern Pacific and warm SSTs in the tropical Atlantic. The hurricane activity of 1995 and 1996 is more reminiscent of activity of some seasons during the early and mid-1950s.
Changes in the Number of Lightning Deaths in the United States during the Twentieth Century
Authors: López Raúl E. , Holle Ronald L.
Published: March 2011

Long-term changes in the number of lightning deaths from 1900 to 1991 have been examined for the contiguous United States. The population-normalized series revealed an exponential decrease in the number of deaths per million people. This exponential trend is also present in the decrease of the rural U.S. population for the period. The two datasets agree remarkably well and this suggests the downward trend in lightning deaths resulted to a large extent from the reduction of the rural population.

Superimposed on the overall downward trend in lightning deaths were fluctuations of two or three decades in duration. The patterns of these fluctuations are paralleled by nationwide changes in thunder-day frequencies and average surface temperature values. Thus, it appears that the lightning death fluctuations are climatically induced.
Response of Climate Simulation to a New Convective Parameterization in the National Center for Atmospheric Research Community Climate Model (CCM3)*
Authors: Zhang Guang J. , Kiehl Jeffrey T. , Rasch Philip J.
Published: March 2011

This study examines the response of the climate simulation by the National Center for Atmospheric Research Community Climate Model (CCM3) to the introduction of the Zhang and McFarlane convective parameterization in the model. It is shown that in the CCM3 the simulated surface climate in the tropical convective regimes, especially in the western Pacific warm pool, is markedly improved, yielding a much better agreement with the recent observations. The systematic bias in the surface evaporation, surface wind stress over the tropical Pacific Ocean in previous model simulations is significantly reduced, owing to the better simulation of the surface flow.

Experiments using identical initial and boundary conditions, but different convection schemes, are performed to isolate the role of the convection schemes and to understand the interaction between convection and the large-scale circulation in a convecting atmosphere. The comparison of the results from these experiments in the western Pacific warm pool suggests that use of the Zhang and McFarlane scheme makes a significant contribution to the improved climate simulation in CCM3. The simulated atmosphere using the Zhang and McFarlane scheme exhibits a quasi-equilibrium between convection and the large-scale processes. When this scheme is removed from the CCM3, such a quasi-equilibrium is no longer observed. In addition, the simulated thermodynamic structures, the surface evaporation, and surface winds in the Pacific warm pool become very similar to those in the CCM2 climate.

Examination of the temporal evolution of the various fields demonstrates that the stabilization of the atmosphere using the new convection scheme takes place during the transition from nonequilibrium to quasi equilibrium at the beginning of the time integration. After quasi equilibrium is reached, the atmosphere is warmer and more stable compared to the run without the new scheme. Associated with the more stable stratification, the atmospheric circulation becomes weaker, thus the surface winds and evaporation are weaker because of the coupling between thermodynamics and dynamics in the tropical troposphere.
Coupled Modes of the Warm Pool Climate System. Part I: The Role of Air–Sea Interaction in Maintaining Madden–Julian Oscillation
Authors: Wang Bin , Xie Xiaosu
Published: March 2011

Over the warm pool of the equatorial Indian and western Pacific Oceans, both the climatological mean state and the processes of atmosphere–ocean interaction differ fundamentally from their counterparts over the cold tongue of the equatorial eastern Pacific. A model suitable for studying the coupled instability in both the warm pool and cold tongue regimes is advanced. The model emphasizes ocean mixed layer physics and thermodynamical coupling that are essential for the warm pool regime. Different coupled unstable modes are found under each regime.

In contrast to the cold tongue basic state, which favors coupled unstable low-frequency SST mode, the warm pool regime (moderate mean surface westerlies and deep thermocline) is conducive for high-frequency (intraseasonal timescale) coupled unstable modes. The wind–mixed layer interaction through entrainment/evaporation plays a central role in the warm pool instability. The cloud-radiation feedback enhances the instability, whereas the ocean wave dynamics have little impact. The thermodynamic coupling between the atmosphere and ocean mixed layer results in a positive SST anomaly leading convection, which provides eddy available potential energy for growing coupled mode. The relatively slow mixed layer response to atmospheric forcing favors the growth of planetary-scale coupled modes. The presence of mean westerlies suppresses the low-frequency SST mode.

The characteristics of the eastward-propagating coupled mode of the warm pool system compares favorably with the large-scale features of the observed Madden–Julian Oscillation (MJO). This suggests that, in addition to atmospheric internal dynamic instability, the ocean mixed layer thermodynamic processes interacting with the atmosphere may play an active part in sustaining the MJO by (a) destabilizing atmospheric moist Kelvin waves, (b) providing a longwave selection mechanism, and (c) slowing down phase propagation and setting up the 40–50-day timescale.
A Pilot Study Examining U.S. Winter Cyclone Frequency Patterns Associated with Three ENSO Parameters
Authors: Noel James , Changnon David
Published: March 2011

Teleconnections were used to link three El Niño–Southern Oscillation (ENSO) parameters to winter (December–February) cyclone frequencies over the United States during the 1949–96 period. Since each ENSO event is not exactly the same, small subsets of ENSO events were examined in addition to the more common composite ENSO event. Mean winter cyclone frequencies, derived by counting cyclones passing through 30, 5° latitude equal-area circles located in a grid from 70° to 120°W and 30° to 50°N were determined for classes of El Niños and La Niñas based on 1) the intensity of the equatorial Pacific sea surface temperature anomaly, 2) the intensity of the Tahiti–Darwin sea level pressure anomaly, and 3) the location of the 28°C isotherm. The average cyclone count for each class of El Niño and La Niña was compared to the average count for winters when no ENSO event occurred.

Expected differences in cyclone frequency patterns when comparing an average of all El Niño winters to all La Niña winters were found; however, large pattern differences were also determined when comparing winters with strong El Niños to moderate–weak El Niños and similarly for La Niñas. Significant differences in number of cyclones were found in 8 of 30 circles located in the Pacific Northwest, the Great Lakes, New England, and the Southeast. The differences found in the cyclone frequency patterns for El Niños and La Niñas of different intensities and locations indicated that using a composite of all El Niños or La Niñas may provide misleading information while examination of each of these parameters independently may assist in the preparation of long-range climate predictions.
Design and Pedestrianism in a Smart Growth Development
Authors: Zook Julie Brand , Lu Yi , Glanz Karen , Zimring Craig
Published: March 2011

Research on urban walkability does not always make a clear distinction between design features supporting walkability and those leading to a sense of urban liveliness. Walkability, for this article’s purposes, entails the opportunity for continuous movement across some distance and therefore engages both the local and global street networks. Urban liveliness, by contrast, may exist in isolated pockets that provide limited support for physical activity. This case study of a large, urban smart growth development in Atlanta, Georgia, provides an example of a new development with characteristics that suggest a high degree of walkability. However, observational data show pedestrians are clumped on relatively few street segments rather than distributed throughout the site, indicating it is unlikely that the site is hosting much walking between the development and its surrounds. This descriptive case study is intended to contribute to more explicit theory of how environmental design contributes to walking.
Daily detachment from work and home: The moderating effect of role salience
Authors: Sanz-Vergel Ana Isabel , Demerouti Evangelia , Bakker Arnold B , Moreno-Jiménez Bernardo
Published: March 2011

Is ‘switching off’ from work and home more or less necessary for individuals depending on role salience? The present study focuses on this question by assessing the importance of trait role salience for the relationship between daily detachment from work and home on the one hand, and several outcomes on the other hand. Forty-nine employees from different organizations in Spain filled out a general questionnaire and a daily questionnaire three times a day, during five consecutive working days. Results show that detaching from home particularly helps individuals with low work role salience to perform better at work and reduce home—work interference. Contrary to our expectations, detaching from work is especially important for individuals with high home role salience, increasing evening cognitive liveliness and reducing work—home interference. Our findings indicate that differences in trait role salience may affect the beneficial impact of detachment from work and non-work domains.
The sub-national embeddedness of international HRM
Authors: Almond Phil
Published: March 2011

This article argues that international human resource management has failed to examine adequately the relations between multinational corporations (MNCs) and the geographies they operate in at sub-national levels. In particular, it needs to go much further in integrating insights from literatures on changing levels of governance, the role of sub-national sites of regulation in the creation and transmission of knowledge, and the geographical and organizational fragmentation of production. In reviewing these literatures alongside relevant contributions within international human resource management, it develops a research agenda by which the degree and nature of sub-national embeddedness of MNCs, and their effects on sub-national business and employment systems, can be analysed.
National institutions and employers’ age management practices in Britain and Germany: ‘Path dependence’ and option exploration
Authors: Muller-Camen Michael , Croucher Richard , Flynn Matt , Schröder Heike
Published: March 2011

We pursue a comparative analysis of employers’ age management practices in Britain and Germany, asking how valid ‘convergence’ and ‘Varieties of Capitalism’ theories are. After rejecting the convergence verdict, we proceed to ask how far ‘path dependence’ helps explain inter-country differences. Through 19 interviews with British and German experts, we find that firms have reacted in different ways to promptings from the EU and the two states. Change has been modest and a rhetoric-reality gap exists in firms as they seek to hedge. We point to continuities in German institutional methods of developing new initiatives, and the emerging role of British NGOs in helping firms and the state develop new options. We argue that ‘path dependence’ offers insight into the national comparison, but also advance the idea of national modes of firm option-exploration as an important way of conceptualizing the processes involved.
Policy transfer from advanced to less-advanced institutional environments: Labour market orientations of US MNEs in Turkey
Authors: Sayım Kadire Zeynep
Published: March 2011

The extant research on policy transfer insufficiently addresses two issues. First, transfer to less-advanced countries. Second, micro-institutional pressures on subsidiaries, particularly the role of local partners in joint ventures (JVs). This study investigates the transfer of labour market orientations by American multinational enterprises to their Turkish subsidiaries by focusing on the influences of macro- and micro-institutional factors when the ‘transferor’ is an advanced and ‘transferee’ is a less-advanced economy, ‘dominance effects’, and the role of local JV partners. Case study findings provide evidence for ‘smooth’ transfer of the policy. This uncommon finding is discussed as a result of ‘ideal combination’ of ‘encouraging pressures’ at the macro- and micro-institutional levels, including role of local JV partners and the nature of the policy transferred.