bluuebunny/crossref_metadata_2025 huggingface dataset:
Acellular Dermal Matrix for Mucogingival Surgery: A Meta‐Analysis
Authors: Gapski Ricardo , Parks Christopher Allen , Wang Hom‐Lay
Published: November 2005

Background: Many clinical studies revealed the effectiveness of acellular dermal matrix (ADM) in the treatment of mucogingival defects. The purpose of this meta‐analysis was to compare the efficacy of ADM‐based root coverage (RC) and ADM‐based increase in keratinized tissues to other commonly used mucogingival surgeries.

Methods: Meta‐analysis was limited to randomized clinical trials (RCT). Articles from January 1, 1990 to October 2004 related to ADM were searched utilizing the MEDLINE database from the National Library of Medicine, the Cochrane Oral Health Group Specialized Trials Registry, and through hand searches of reviews and recent journals. Relevant studies were identified, ranked independently, and mean data from each were weighted accordingly. Selected outcomes were analyzed using a meta‐analysis software program. The significant estimates of the treatment effects from different trials were assessed by means of Cochrane's test of heterogeneity.

Results: 1) Few RCT studies were found to compile the data. In summary, selection identified eight RCT that met the inclusion criteria. There were four studies comparing ADM versus a connective tissue graft for root coverage procedures, two studies comparing ADM versus coronally advanced flap (CAF) for root coverage procedures, and two studies comparing ADM to free gingival graft in augmentation of keratinized tissue. 2) There were no statistically significant differences between groups for any of the outcomes measured (recession coverage, keratinized tissue formation, probing depths, and clinical attachment levels). 3) The majority of the analyses demonstrated moderate to high levels of heterogeneity. 4) Considering the heterogeneity values found among the studies, certain trends could be found: a) three out of four studies favored the ADM‐RC group for recession coverage; b) a connective tissue graft tended to increase keratinized tissue compared to ADM (0.52‐mm difference; P = 0.11); c) there were trends of increased clinical attachment gains comparing ADM to CAF procedures (0.56‐mm difference; P = 0.16).

Conclusions: Differences in study design and lack of data precluded an adequate and complete pooling of data for a more comprehensive analysis. Therefore, considering the trends presented in this study, there is a need for further randomized clinical studies of ADM procedures in comparison to common mucogingival surgical procedures to confirm our findings. It is difficult to draw anything other than tentative conclusions from this meta‐analysis of ADM for mucogingival surgery, primarily because of the weakness in the design and reporting of existing trials.
Treatment of Gingival Recession: Comparison of Two Techniques of Subepithelial Connective Tissue Graft
Authors: Tözüm Tolga F. , Keçeli H. Gencay , Güncü Güliz N. , Hatipoğlu Hasan , Şengün Dilek
Published: November 2005

Background: The increasing interest in esthetics and the subsequent need to solve related problems such as hypersensitivity and root caries have favored the development of many surgical procedures that permit the coverage of exposed roots. This clinical study was conducted to examine the coverage of gingival recession defects, where two different subepithelial connective tissue graft (SCTG) techniques (Langer and Langer and modified tunnel) were used.

Methods: Thirty one patients (21 females and 10 males), each contributing Miller Class I and II gingival recessions, were selected. Recession defects were randomly treated by using the Langer and Langer technique (17 patients) or the modified tunnel technique (14 patients). Vertical recession, probing depth (PD), and attachment level were assessed at baseline and 6 months postoperatively.

Results: Six months after the surgery, a significant reduction in recession depth was noticed in both groups. There was also a decrease of PD and attachment level for both groups, but not statistically significant. In comparison, at 6 months, statically significant differences were found between the tunnel and Langer and Langer techniques for root coverage and attachment gain. The percentage of root coverage was 96.4% and 75.5% in the tunnel and Langer and Langer groups, respectively.

Conclusions: The present study suggests that the use of SCTG in combination with a tunnel procedure may result in an increased amount of root coverage and clinical attachment gain compared to the Langer and Langer technique. Further comparative studies are necessary to understand the periodontal healing generated by the tunnel procedure and Langer and Langer technique.
Gingival Crevicular Fluid Levels of Monocyte Chemoattractant Protein‐1 and Tumor Necrosis Factor‐Alpha in Patients With Chronic and Aggressive Periodontitis
Authors: Kurtiş Bülent , Tüter Gülay , Serdar Muhittin , Akdemir Pelin , Uygur Cem , Firatli Erhan , Bal Belgin
Published: November 2005

Background: Monocyte chemoattractant protein‐1 (MCP‐1) is a well‐known chemotactic cytokine that regulates mononuclear inflammatory cell recruitment. This recruitment has particular importance in the oral cavity because inflammatory cells will be challenged with periodontopathogenic bacteria during infections. Tumor necrosis factor‐alpha (TNF‐α) is a cytokine that induces bone resorption by stimulating proliferation and differentiation of osteoclasts’ progenitors and also stimulates MCP‐1 expression. The aims of this study were to investigate the presence of MCP‐1 in gingival crevicular fluid (GCF) samples from patients with chronic periodontitis (CP) and aggressive periodontitis (AgP) and to examine the possible correlations between the GCF levels of MCP‐1 and TNF‐α.

Methods: Twenty‐five CP, 20 AgP, and 20 healthy control (C) patients were selected for the study. Plaque index (PI), gingival index (GI), probing depth (PD), and clinical attachment level (CAL) measurements were recorded from each sampling area. Assays for GCF MCP‐1 and TNF‐α were carried out by an enzyme‐linked immunosorbent assay (ELISA) method.

Results: The concentration (nanograms per microliters) and total MCP‐1 and TNF‐α (nanograms per site) were not statistically significant between CP and AgP groups, but total MCP‐1 and TNF‐α was statistically different between CP and C and between AgP and C groups (P <0.001). All clinical parameters were statistically different between CP and C and between AgP and C groups (P <0.001). A positive statistical correlation was detected between the levels of MCP‐1 and TNF‐α, and there was also a positive correlation between all clinical parameters and total MCP‐1 and TNF‐α levels.

Conclusions: These results suggest that MCP‐1 could have an important role in the activation and recruitment of inflammatory and immune cells in periodontal diseases, and both AgP and CP patients may have the same pattern of MCP‐1 expression. A strong positive correlation between the GCF levels of MCP‐1 and TNF‐α may account for the mechanism of amplification of inflammatory events in gingival inflammation.
Local Simvastatin Effects on Mandibular Bone Growth and Inflammation
Authors: Stein David , Lee Yeonju , Schmid Marian J. , Killpack Byron , Genrich Mikala A. , Narayana Nagamani , Cullen Diane M. , Reinhardt Richard A. , Marx David B.
Published: November 2005

Background: Simvastatin has been shown to increase bone growth when applied topically to murine bone; however, it causes considerable soft tissue inflammation at high doses (2.2 mg), making future clinical use problematic. This study evaluated the effect of lower simvastatin doses and cyclooxygenase (COX) synthase inhibitors on tissue inflammation and bone growth in rats and gene expression in mice.

Methods: Adult female rats were untreated or treated with a single dose of 0.1, 0.5, 1.0, 1.5, or 2.2 mg simvastatin in methylcellulose gel in a polylactic acid membrane (SIM) on the lateral aspect of the mandible. The contralateral mandible side was implanted with methylcellulose gel/polylactic acid membrane alone (GEL), and five rats in each dose pairing were evaluated histomorphometrically after 3, 7, and 24 days. Subsequent rats were similarly treated with 0.5 mg simvastatin (optimal dose) and daily intraperitoneal injections of COX‐2 inhibitor (NS‐398; 1 mg/kg × 7 days; N = 16), general COX inhibitor (indomethacin; 1 mg/kg × 7 days; N = 16), or no inhibitor (N = 10) and evaluated histomorphometrically after 7 or 24 days by analysis of variance (ANOVA). Gene arrays were also used to evaluate osteogenic gene expression from 0.5 mg simvastatin in murine calvaria (N = 12).

Results: There was a 45% increase in bone area with 0.5 mg simvastatin versus gel control (P <0.001; similar to the 2.2‐mg dose), and clinical swelling was reduced compared to the high simvastatin dose (P <0.05). The 0.1‐mg simvastatin dose failed to stimulate significant bone growth. NS‐398 and indomethacin reduced inflammation and bone growth. Simvastatin significantly upregulated procollagen, fibronectin, and matrix metalloproteinase‐13 genes.

Conclusion: Reducing the simvastatin dose from 2.2 to 0.5 mg reduced inflammation to a more clinically acceptable level without sacrificing bone‐growth potential, but COX‐associated inflammation appears to be necessary for in vivo bone growth.
Plasma Levels of Mannan‐Binding Lectin in Relation to Periodontitis and Smoking
Authors: Maffei Gaia , Brouwer Nannette , Dolman Koert M. , van der Velden Ubele , Roos Dirk , Loos Bruno G.
Published: November 2005

Background: Mannan‐binding lectin (MBL) is an important molecule of innate immunity; it acts as an opsonin and stimulates the classical complement pathway. Moreover, it has been suggested that MBL acts as a weak acute phase protein. We investigated whether MBL levels are increased in periodontitis, and we tested whether individuals deficient for MBL are more susceptible to periodontitis.

Methods: A total of 219 subjects participated in the study. Plasma samples from 115 periodontitis patients and 104 healthy controls were taken, and the MBL levels were measured by enzyme‐linked immunosorbent assay (ELISA). MBL levels were analyzed in relation to periodontitis, taking into consideration age, gender, ethnic and educational background, and smoking status. In some analyses, subjects with MBL plasma levels <0.8 μg/ml were considered MBL deficient.

Results: MBL plasma concentrations were not significantly different in moderate and severe periodontitis compared to controls (1.6, 1.4, and 1.6 μg/ml, respectively). Also, the prevalence of MBL deficiency was not found to be different between controls and moderate and severe periodontitis (45%, 37%, and 36%). However, among all subjects and among the non‐deficient subjects, MBL levels were markedly increased in heavy smokers (>10 cigarettes per day), irrespective of periodontal disease status, in comparison to non‐smokers and light smokers. MBL plasma levels did not show a correlation with plasma C‐reactive protein (CRP) and were also not related to the prevalence of specific periodontal pathogens.

Conclusions: MBL levels were not elevated in periodontitis, and MBL deficiency was not related to susceptibility for periodontitis. The fact that MBL levels were higher among heavy smokers is the subject of further investigation.
Risk Indicators for Tooth Loss Due to Periodontal Disease
Authors: Al‐Shammari Khalaf F. , Al‐Khabbaz Areej K. , Al‐Ansari Jassem M. , Neiva Rodrigo , Wang Hom‐Lay
Published: November 2005

Background: Several risk indicators for periodontal disease severity have been identified. The association of these factors with tooth loss for periodontal reasons was investigated in this cross‐sectional comparative study.

Methods: All extractions performed in 21 general dental practice clinics (25% of such clinics in Kuwait) over a 30‐day period were recorded. Documented information included patient age and gender, medical history findings, dental maintenance history, toothbrushing frequency, types and numbers of extracted teeth, and the reason for the extraction. Reasons were divided into periodontal disease versus other reasons in univariate and binary logistic regression analyses.

Results: A total of 1,775 patients had 3,694 teeth extracted. More teeth per patient were lost due to periodontal disease than for other reasons (2.8 ± 0.2 versus 1.8 ± 0.1; P <0.001). Factors significantly associated with tooth loss due to periodontal reasons in logistic regression analysis were age >35 years (odds ratio [OR] 3.45; 95% confidence interval [CI] 2.79 to 4.26), male gender (OR 1.42; 95% CI 1.17 to 1.73), never having periodontal maintenance (OR 1.48; 95% CI 1.23 to 1.78), never using a toothbrush (OR 1.81; 95% CI 1.49 to 2.20), current or past smoking (OR 1.56; 95% CI 1.28 to 1.91), anterior tooth type (OR 3.23; 95% CI 2.57 to 4.05), and the presence of either of the following medical conditions: diabetes mellitus (OR 2.64; 95% CI 2.19 to 3.18), hypertension (OR 1.73; 95% CI 1.41 to 2.13), or rheumatoid arthritis (OR 4.19; 95% CI 2.17 to 8.11).

Conclusion: Tooth loss due to periodontal disease is associated with the risk indicators of age, male gender, smoking, lack of professional maintenance, inadequate oral hygiene, diabetes mellitus, hypertension, rheumatoid arthritis, and anterior tooth type.
Tobacco Smoking and Periodontal Health in a Saudi Arabian Population
Authors: Natto Suzan , Baljoon Mostafa , Bergström Jan
Published: November 2005

Background: The objective of this study was to examine the association between tobacco smoking, in particular water pipe smoking, and periodontal health.

Methods: A total of 262 citizens of Jeddah, Saudi Arabia in the age range from 17 to 60 years volunteered to participate in the study. The clinical examinations were carried out at King Faisal Specialty Hospital and Research Center in Jeddah and included assessments of oral hygiene, gingival inflammation, and probing depth. Smoking behavior was registered through a questionnaire and confirmed by an interview. Participants were stratified into water pipe smokers (31%), cigarette smokers (19%), mixed smokers (20%), and non‐smokers (30%).

Results: The mean probing depth per person was 3.1 mm for water pipe smokers, 3.0 mm for cigarette smokers, 2.8 mm for mixed smokers, and 2.3 mm for non‐smokers. The association between smoking and probing depth was statistically significant controlling for age (P <0.001). The association between lifetime smoking exposure and mean probing depth was statistically significant in water pipe as well as cigarette smokers controlling for age (P <0.001). Using multivariate analysis, besides smoking, the gingival and plaque indexes were associated with increased probing depth. The prevalence of periodontal disease defined as a minimum of 10 sites with a probing depth ≥5 mm was 19.5% in the total population, 30% in water pipe smokers, 24% in cigarette smokers, and 8% in non‐smokers. The prevalence was significantly greater in water pipe and cigarette smokers compared to non‐smokers (P <0.001). The relative risk for periodontal disease increased by 5.1‐ and 3.8‐fold in water pipe and cigarette smokers, respectively, compared to non‐smokers (P <0.001 and P <0.05, respectively).

Conclusions: An association was observed between water pipe smoking and periodontal disease manifestations in terms of probing depth measurements. The impact of water pipe smoking was of largely the same magnitude as that of cigarette smoking.
In Vitro, Clinical, and Microbiological Evaluation of a Linear Oscillating Device for Scaling and Root Planing
Authors: Rupf Stefan , Brader Iris , Vonderlind Doris , Kannengiesser Sabine , Eschrich Klaus , Roeder Ingo , Merte Knut
Published: November 2005

Background: The purpose of this study was to conduct an in vitro and short‐term clinical and microbiological evaluation of a linear oscillating device for scaling and root planing (SRP). A comparison was made between conventional ultrasonic scaling (US) and hand scaling (HS) with and without chlorhexidine.

Methods: In vitro, SRP was carried out on human teeth with calculus. Roots and cross‐sections thereof were microscopically examined for the efficacy of calculus removal, hard tissue loss, and surface smoothness. In vivo, 11 patients with chronic periodontitis and single‐rooted teeth in all quadrants with probing depths of ≥5 mm were selected. One quadrant was treated with linear oscillation and compared to US with chlorhexidine irrigation in the contralateral site. The other arch was treated with HS and compared to HS followed by laser disinfection. One hundred twenty teeth were assessed for clinical attachment level, probing depth, bleeding on probing, and suppuration at baseline and 7, 28, 90, and 180 days. Microbiologically, total numbers of bacteria and six specific periodontal pathogens were determined by quantitative polymerase chain reaction prior to and 1 and 28 days after SRP. Clinical and microbiological data were analyzed statistically with respect to the SRP method, patient specificity, and time effect.

Results: In vitro, linear oscillation preserved more root tissues but left more calculus (P <0.05). Significant improvements of all clinical and microbiological parameters were observed for all groups. However, 21 out of 24 tests demonstrated that the clinical microbiological correlations between linear oscillation and control groups did not differ (P <0.05).

Conclusion: Linear oscillation scaling was clinically acceptable and microbiologically comparable to the control groups despite microscopic remnants of calculus observed in vitro.
CD38 Expression in Neutrophils From Patients With Localized Aggressive Periodontitis
Authors: Fujita Tsuyoshi , Kantarci Alpdogan , Warbington Martha L. , Zawawi Khalid H. , Hasturk Hatice , Kurihara Hidemi , Van Dyke Thomas E.
Published: November 2005

Background: Localized aggressive periodontitis (LAgP) is associated with neutrophil dysfunction including decreased chemotaxis and reduced calcium entry. It has been suggested that CD38 is involved in chemotaxis. Little is known, however, about the relationship of CD38 and LAgP patients. In this study, we focused on the level of CD38 expression between LAgP and normal subjects and examined the involvement of CD38 in abnormal neutrophil chemotaxis of LAgP patients.

Methods: Neutrophils from 12 normal subjects and 12 LAgP patients were isolated from peripheral venous blood. Membrane associated proteins were extracted from cells with or without N‐formylmethionine leucyl‐phenylalanine (fMLP) stimulation. CD38 expression was measured using Western blotting. Band density was measured using an imaging densitometer.

Results: There was no statistical difference between normal subjects and LAgP patients in resting CD38 expression (basal level). However, the fMLP‐stimulated neutrophils exhibited a significant decrease of CD38 expression in LAgP subjects compared to normal subjects. The decrease of CD38 was positively correlated with the defect in chemotactic migration to fMLP.

Conclusion: These data suggest that the lower expression of CD38 in neutrophils may be related to altered neutrophil function in LAgP.
Periodontal Microcirculatory Abnormalities in Patients With Systemic Sclerosis
Authors: Scardina G.A. , Pizzigatti M.E. , Messina P.
Published: November 2005

Background: The aim of this study was to observe the differences in periodontal microcirculation between healthy patients and patients with systemic sclerosis (SSc).

Methods: Fifteen healthy patients and 15 patients with SSc were examined. Periodontal capillaroscopy was used to investigate the characteristics of microcirculation. The visibility, course, tortuosity, possible presence of microhemorrhages, average caliber of the capillary loops, and number of visible capillary loops per square millimeter were evaluated for each patient.

Results: The investigation was simple, non‐invasive, and repeatable for each patient. In patients with SSc, it was possible to observe a reduced number of capillaries and a greater capillary diameter and tortuosity.

Conclusions: Capillary alterations in patients with SSc are not limited to the nailfold bed but also occur in periodontal mucosa microcirculation. Such evidence could be extremely important in the pathogenesis and treatment of periodontal diseases in patients with SSc.
Papillon‐Lefèvre Syndrome: A Successful Outcome
Authors: Ahuja Vanita , Shin Richard Hochul , Mudgil Adarsh , Nanda Veena , Schoor Robert
Published: November 2005

Background: Papillon‐Lefèvre syndrome (PLS) is a rare autosomal recessive condition manifested clinically by hyperkeratosis of the palms and soles and rapidly progressive periodontitis resulting in loss of deciduous and permanent teeth. This case report describes the clinical periodontal findings and treatment of a 10‐year‐old male patient with PLS. The patient provided informed consent, and the study was conducted in accordance with the Helsinki Declaration of 1975, as revised in 2000.

Methods: Upon initial presentation, a full periodontal examination was completed. Conventional probing depths, clinical attachment levels (CAL), gingival index (GI), and plaque index (PI) were measured prior to initial therapy, which involved oral hygiene instruction and scaling and root planing. At reevaluation, initial treatment proved unsuccessful, and a surgical approach with concomitant systemic antibiotic therapy was implemented. In addition, the patient's dermatologist treated his palmoplantar keratoderma with systemic retinoids. Subsequently, the patient was placed on a strict 3‐month maintenance protocol and was evaluated over a period of 1 year.

Results: Initial treatment with mechanical therapy, oral hygiene instruction, frequent recalls, and systemic antibiotics did not yield efficacious results. However, with the addition of surgical treatment, a favorable clinical outcome was obtained.

Conclusions: Numerous treatment regimens for the periodontal disease seen in PLS can be found in the literature. We demonstrate successful treatment of the periodontal disease seen in this condition using mechanical therapy, systemic antibiotics, and surgical modalities; over a period of 1 year, we were able to achieve significant reductions in gingival inflammation and erythema.
Progressive, Generalized, Apical Idiopathic Root Resorption and Hypercementosis
Authors: Schätzle Marc , Tanner Sandro D. , Bosshardt Dieter D.
Published: November 2005

Background: Root resorption is a multifactorial process that results in loss of tooth structure. The causes of root resorption may vary, leading to several types of resorptions. Some factors have been identified and may be categorized into physiological resorption, local factors, systemic conditions, and idiopathic resorptions. The objective of this report was to present a case of a 17‐year‐old white female with progressive, generalized, apical idiopathic root resorption followed up for 34 months.

Methods: Two panoramic radiographs, 14 and 34 months after initial clinical and radiological examinations, showed the rapid progression of apical root resorption. Two molars, teeth #15 and #16, which had to be extracted, and a bone sample from the distal aspect of tooth #15 were processed for histologic analysis.

Results: Two millimeters apical to the cemento‐enamel junction, an abrupt increase in the cementum thickness was noted, amounting to 300 and 800 μm in teeth #15 and #16, respectively. The thickening of the cementum layer was due to an accelerated deposition of cellular intrinsic fiber cementum. An unusually high number of mineralization foci were observed in association with acellular extrinsic fiber cementum, and both free and fused cementicles were seen. In contrast to tooth #16, tooth #15 revealed extensive dentin replacement by a bone‐like and a cementum‐like tissue. Furthermore, ankylosis was demonstrated in tooth #15 and confirmed in the bone sample.

Conclusions: At present, there is no preventive or therapeutic regimen for the type of root resorption seen in this case report. Treatment usually consists of the extraction of teeth with advanced lesions.
Adaptive Activation of Thyroid Hormone and Energy Expenditure
Authors: Bianco Antonio C. , Maia Ana Luiza , da Silva Wagner Seixas , Christoffolete Marcelo A.
Published: November 2005

The mechanisms by which thyroid hormone accelerates energy expenditure are poorly understood. In the brown adipose tissue (BAT), activation of thyroid hormone by type 2 iodothyronine deiodinase (D2) has been known to play a role in adaptive energy expenditure during cold exposure in human newborns and other small mammals. Although BAT is not present in significant amounts in normal adult humans, recent studies have found substantial amounts of D2 in skeletal muscle, a metabolically relevant tissue in humans. This article reviews current biological knowledge about D2 and adaptive T3 production and their roles in energy expenditure.
Thermoregulation: What Role for UCPs in Mammals and Birds?
Authors: Mozo Julien , Emre Yalin , Bouillaud Frederic , Ricquier Daniel , Criscuolo Francois
Published: November 2005

Mammals and birds are endotherms and respond to cold exposure by the means of regulatory thermogenesis, either shivering or non-shivering. In this latter case, waste of cell energy as heat can be achieved by uncoupling of mitochondrial respiration. Uncoupling proteins, which belong to the mitochondrial carrier family, are able to transport protons and thus may assume a thermogenic function. The mammalian UCP1 physiological function is now well understood and gives to the brown adipose tissue the capacity for heat generation. But is it really the case for its more recently discovered isoforms UCP2 and UCP3? Additionally, whereas more and more evidence suggests that non-shivering also exists in birds, is the avian UCP also involved in response to cold exposure? In this review, we consider the latest advances in the field of UCP biology and present putative functions for UCP1 homologues.
Diltiazem treatment prevents diastolic heart failure in mice with familial hypertrophic cardiomyopathy
Authors: Westermann Dirk , Knollmann Björn C. , Steendijk Paul , Rutschow Susanne , Riad Alexander , Pauschinger Matthias , Potter James D. , Schultheiss Heinz‐Peter , Tschöpe Carsten
Published: November 2005

Background:

The cardiac troponin T I79N mutation, linked to familial hypertrophic cardiomyopathy, carries a high risk of sudden cardiac death even in the absence of significant cardiac hypertrophy. The pathology underlying this mechanism has not yet been identified.

Aims:

To study the underlying mechanism of this phenomenon we characterized the left ventricular (LV) performance of transgenic mice carrying the human troponin T mutation I79N under basal and isoproterenol‐induced stress conditions.

Methods and results:

LV function was analyzed by recording pressure—volume loops using a microconductance catheter. Despite a hypercontractile systolic function under basal conditions TnT‐I79N mice showed a diastolic dysfunction indicated by an increase in end‐diastolic pressure—volume relationship (EDPVR), a load‐independent factor of LV stiffness (0.06±0.01 vs. 0.02±0.01; P<0.05), when compared to mice expressing human wild‐type troponin T (TnT‐WT). TnT‐I79N mutants developed severe diastolic heart failure and cardiac sudden death under isoproterenol stress. This was prevented after pretreatment with the L‐type Ca2+ channel inhibitor diltiazem.

Conclusions:

Diastolic dysfunction due to increased LV stiffness in TnT‐I79N mice leads to severe primary diastolic heart failure and finally to cardiac sudden death, which can be prevented by diltiazem.
Genetic evidence that the northern calamary, Sepioteuthis lessoniana, is a species complex in Australian waters
Authors: Triantafillos Lianos , Adams Mark
Published: November 2005

Allozyme electrophoresis was used to investigate the taxonomic status of northern calamary Sepioteuthis lessoniana (Lesson 1830) from two sites in Shark Bay, Western Australia. Of the 40 squid examined at 38 presumptive loci, four individuals from the oceanic site were clearly differentiated from the rest by fixed allelic differences at four loci (Acp, Got2, Idh2, and PepD) and near-fixed differences at another three (Est, Ocdh, and 6Pgd). The genetic distances between these two groups of individuals (13% Fixed Differences and Nei, D (1978) = 0.178) were roughly twofold greater than those between the two cryptic taxa in the southern calamary S. australis, but are considerably smaller than those between the northern and southern calamary. The most likely explanation for these data is that S. lessoniana comprises two “cryptic” biological species in this region. Further studies are needed to delineate the total number of species found throughout Australasia for this important loliginid squid.
Models of lithosphere and asthenosphere anisotropic structure of the Yellowstone hot spot from shear wave splitting
Authors: Waite Gregory P. , Schutt Derek L. , Smith Robert B.
Published: November 2005

Teleseismic shear wave splitting measured at 56 continuous and temporary seismographs deployed in a 500 km by 600 km area around the Yellowstone hot spot indicates that fast anisotropy in the mantle is parallel to the direction of plate motion under most of the array. The average split time from all stations of 0.9 s is typical of continental stations. There is little evidence for plume‐induced radial strain, suggesting that any contribution of gravitationally spreading plume material is undetectably small with respect to the plate motion velocity. Two stations within Yellowstone have splitting measurements indicating the apparent fast anisotropy direction (ϕ) is nearly perpendicular to plate motion. These stations are ∼30 km from stations with ϕ parallel to plate motion. The 70° rotation over 30 km suggests a shallow source of anisotropy; however, split times for these stations are more than 2 s. We suggest melt‐filled, stress‐oriented cracks in the lithosphere are responsible for the anomalous ϕ orientations within Yellowstone. Stations southeast of Yellowstone have measurements of ϕ oriented NNW to WNW at high angles to the plate motion direction. The Archean lithosphere beneath these stations may have significant anisotropy capable of producing the observed splitting.
Inverse modeling of biomass burning emissions using Total Ozone Mapping Spectrometer aerosol index for 1997
Authors: Zhang Sophia , Penner Joyce E. , Torres Omar
Published: November 2005

We present results from an inverse model study to determine biomass smoke emissions for the year 1997 by comparison of modeled aerosol index (AI) with that measured by the EP TOMS instrument. The IMPACT model with Data Assimilation Office (DAO) meteorology data in 1997 is utilized to obtain aerosol spatial and temporal distributions. Then a radiative transfer model is applied to generate the modeled AI. A Bayesian inverse technique is applied to optimize the difference between the modeled AI and the EP TOMS AI in the same period by regulating monthly a priori biomass smoke emissions in seven predefined regions. The modeled AI with a posteriori emissions is generally in better agreement with the EP TOMS AI. The a posteriori emissions from Indonesia increase by a factor of 8–10 over the a priori emissions due to the Indonesian fires in 1997. The annual total a posteriori source increases by about 13% for the year 1997 (6.31 Tg/yr black carbon and 67.27 Tg/yr smoke) in the base scenario, with a larger adjustment of monthly emissions. The sensitivity of this result to the a priori uncertainties, the height of the smoke layer, the cloud screening criteria, the inclusion of an adjustment of emissions outside the main biomass burning regions, and the inclusion of the covariances between observations in different locations is discussed in a set of sensitivity scenarios. The sensitivity scenarios suggest that the inverse model results are most sensitive to the assumed uncertainty for a priori emissions and the altitude of aerosol layer in the model and are less sensitive to other factors. In the scenario where the uncertainty of a priori emissions is increased to 100% (300% in Indonesia), the total annual black carbon emission is increased to 6.87 Tg/yr, and the smoke emission increases to 73.39 Tg/yr. The a posteriori emissions in Indonesia in the scenario with increased uncertainty are in better agreement with both the TOMS AI and with previous estimates for the Indonesian fires in 1997. In the scenario where biomass smoke from large fires are elevated by 1 km in altitude, the annual total black carbon emissions are 5.68 Tg/yr, and the smoke emissions are 60.44 Tg/yr, almost unchanged from the a priori emissions.
Flow diversion around cavities in fractured media
Authors: Ghezzehei Teamrat A.
Published: November 2005

Flow diversion around subsurface cavities in unsaturated fractured media is important to numerous environmental and engineering applications. This paper provides analytical solutions to partial and complete flow diversion around cavities intersected by fractures under steady state conditions. It is focused on a typical trifracture junction located upstream from a cavity surface. Fractures are modeled as two‐dimensional porous media with an exponential relationship between the capillary pressure and unsaturated hydraulic conductivity. The solutions show that the vertical distance between the fracture end and the nearest junction (Z) and the slope of the unsaturated hydraulic conductivity (α) are by far the most important determinants of flow diversion. In fact, the product of Z and α enters the threshold flux and liquid entry flux equations as a dimensionless sorptive length (s). This relationship between Z and α is shown to have important implications for uncertainty and scalability of calibrated model parameters. The solutions given in this paper are expected to be directly applicable to cavities on the order of the fracture spacing.
Slowdown of the thermohaline circulation causes enhanced maritime climate influence and snow cover over Europe
Authors: Jacob Daniela , Goettel Holger , Jungclaus Johann , Muskulus Michael , Podzun Ralf , Marotzke Jochem
Published: November 2005

The ocean thermohaline circulation (THC) in the Atlantic is generally accepted to contribute to the comparatively mild climate of western and northern Europe. Global climate models (Manabe and Stouffer, 1995; Vellinga and Wood, 2002) and palaeo‐observations (McManus et al., 2004) associate periods of weak or absent Atlantic THC with considerably lower temperatures in and around the northern North Atlantic. However, it is uncertain whether such change would spread longitudinally around the globe or would be limited to a narrow strip near the coast (Vellinga and Wood, 2002; Mikolajewicz et al., 1997). Moreover, the relatively low spatial resolution of global climate models has prohibited more detailed statements about possible or probable THC‐induced climate change in Europe. Here, we first use a global climate model to perform a THC‐slowdown sensitivity experiment, with a weakening of the MOC by about 50%, and the associated control experiment. The two global simulations are then used to force a regional climate model for Europe; the regional control and sensitivity simulations are analyzed here. We find stronger maritime influence over Europe than in the case with no MOC weakening, which surprisingly results in cooling (because sea surface temperatures drop), contrary to today's conditions, where maritime influence leads to milder conditions in Europe. Lower temperatures cause reduced precipitation, increased snow cover and higher albedo leading to positive feedback.
Recovery of the tropical lower stratospheric ozone layer
Authors: Rosenfield Joan E. , Schoeberl Mark R.
Published: November 2005

Long‐term time dependent simulations out to the year 2050 using the Goddard Space Flight Center interactive 2D chemistry‐radiation‐dynamics model are used to predict tropical lower stratospheric ozone. The model results show that when chlorine levels are enhanced, heterogeneous chemistry on the surfaces of middle and high latitude sulfate aerosols and polar stratospheric clouds induces circulation changes which lead to ozone depletion in the tropical lower stratosphere. We find that despite a return to background chlorine levels, the tropical lower stratospheric ozone layer will not recover because of a reduction in penetrating ultraviolet radiation. This reduction is due to the faster upper stratospheric ozone recovery with increasing carbon dioxide. With background aerosol amounts, tropical ozone at 50 hPa is reduced by ∼2% between 1980 and 1997 and remains at that level of depletion out to 2050. The simulations also suggest that tropical tropopause temperatures will be lowered by a maximum of 0.1 K between 1980 and 2015, resulting in a maximum reduction of tropical lower stratospheric water vapor of 2% between 1980 and 2018. These results may have important implications for recovery detection strategies.
The intrusive process leading to the Mt. Etna 2001 flank eruption: Constraints from 3‐D attenuation tomography
Authors: Martínez‐Arévalo Carmen , Patanè Domenico , Rietbrock Andreas , Ibánez Jesús M.
Published: November 2005

We have analyzed 291 shallow seismic events, leading to the July 17‐August 9, 2001 flank eruption at Mt. Etna volcano, to obtain high resolution three‐dimensional (3‐D) images of seismic attenuation of P waves (Qp) down to 2 km depth. 2293 P wave spectra have been inverted for seismic attenuation to calculate t* values, considering a frequency‐independent Q, and a ω2‐type source model. The 3‐D tomographic images reveal an anomalous region of very low Qp values (between 10 and 30), located in the same place where the 2001 dike emplaced. We interpret this anomaly as the effect of fluid intrusion (magma rich in gas) in the uppermost part of the Etna volcano, just before the 2001 eruption. This confirms that attenuation is a physical parameter sensitive to the thermal state of crustal volumes through which seismic waves travel.
Coupled ocean‐atmosphere response to north tropical Atlantic SST: Tropical Atlantic dipole and ENSO
Authors: Wu Lixin , He Feng , Liu Zhengyu
Published: November 2005

The coupled ocean‐atmosphere response to changes of the north tropical Atlantic (NTA) SST is investigated using a coupled ocean‐atmosphere general circulation model. The model explicitly demonstrates that a NTA SST anomaly can organize an inter‐hemispheric SST dipole in boreal spring over both the tropical Atlantic and eastern tropical Pacific primarily through a coupled wind‐evaporative‐SST (WES) feedback. While the tropical Atlantic dipole eventually decays in summer and fall, the eastern tropical Pacific dipole subsequently evolves into an ENSO‐like pattern through the seasonal migration of the ITCZ and coupled ocean‐atmosphere feedbacks.
Hydrologic resilience of the terrestrial biosphere
Authors: Gerten Dieter , Lucht Wolfgang , Schaphoff Sibyll , Cramer Wolfgang , Hickler Thomas , Wagner Wolfgang
Published: November 2005

We quantify the extent to which net primary production (NPP) of terrestrial ecosystems is water‐limited under future atmospheric CO2 enrichment and climate change. Analysis is based on spatially explicit simulations with a Dynamic Global Vegetation Model (DGVM) forced by climate projections from five different General Circulation Models (GCMs) under one emission scenario. We find for many but not all regions that NPP will be less water‐limited despite concurrent declines in soil moisture, owing to a frail balance of unfavorable climate effects on soil moisture, reduced transpiration by CO2‐induced lower stomatal aperture, and continuous acclimation of vegetation.
Derivation of a soil albedo dataset from MODIS using principal component analysis: Northern Africa and the Arabian Peninsula
Authors: Zhou Liming , Dickinson Robert E. , Tian Yuhong
Published: November 2005

This paper analyzes MODIS 1 km albedo kernels of 7 spectral bands over Northern Africa and the Arabian Peninsula and through these kernels develops a new high quality dataset that provides a simple statistical method to scale up spectral and broadband albedos from pixel to arbitrary coarse resolution grid square for use in climate models. This dataset significantly improves characterization of spatial and spectral variability and solar zenith angle dependence of soil albedo relative to simple grid means from MODIS data. The statistical method based on minimum noise fraction rotation transforms is able to not only successfully capture most of the MODIS albedo variance but also to extract large‐scale spatial structures of albedo patterns from the original MODIS data while improving the data quality and reducing the number of parameters needed to represent the data.
Diurnal and subdiurnal effects of the atmosphere on the Earth rotation and geocenter motion
Authors: de Viron Olivier , Schwarzbaum Gaëtan , Lott Francois , Dehant Véronique
Published: November 2005

The diurnal cycle in the atmospheric angular momentum (AAM) and in the wind and surface pressure fields is studied with a realistic atmospheric general circulation model (GCM) in which the AAM budget is very well closed. For this, we used a 1 year simulation. From a geodetic point of view, we find that this model predicts AAM variations at diurnal timescale which produce a polar motion near 0.2 milliarc second. Additionally, at the same period, the model predicts a geocenter motion of the order of a millimeter. These results are compared with those obtained with the National Centers for Environmental Prediction/National Center for Atmospheric Research and the European Centre for Medium‐Range Weather Forecasts operational analysis data sets. As the AAM budget is not exactly closed in those two data sets, large quantitative differences with the GCM are found. These results witness that there are problems in using AAM values from the major weather prediction center to estimate the AAM and torques variation at diurnal and subdiurnal timescales. We have also computed, for the three models, the spherical harmonics decomposition of the diurnal and semidiurnal surface pressure signals. The results show large differences from one model to another, which advices carefulness when correcting gravity missions (as Gravity Recovery and Climate Experiment (GRACE), for instance) from the high‐frequency effect of the atmosphere on the orbit, using operational analysis.
Chemical composition of atmospheric nanoparticles during nucleation events in Atlanta
Authors: Smith James N. , Moore Katharine F. , Eisele Fred L. , Voisin Didier , Ghimire Ajaya K. , Sakurai Hiromu , McMurry Peter H.
Published: November 2005

We report the first direct, in situ measurements of the chemical composition of size‐segregated atmospheric nanoparticles in the 6–15 nm diameter range. These measurements were made of ambient aerosol directly following nucleation events in Atlanta, Georgia, during the 2002 Aerosol Nucleation and Real‐time Characterization Experiment (ANARChE). The recently developed Thermal Desorption Chemical Ionization Mass Spectrometer (TDCIMS) was used to make these measurements and featured a new inlet that delivers mass of charged and size‐segregated nanoparticles at sufficiently high rates to enable analysis at a typical time resolution of 10 min. Measurements in both the positive and negative ion spectra revealed that particles formed recently from nucleation events have enhanced concentrations of ammonium and sulfate and that to within the uncertainty of our measurements, ammonium sulfate could account for all of the sampled nanoparticle mass. No other compounds were detected in the particles during these events. Concurrent measurements of particle hygroscopicity and volatility, made using a Nanometer Tandem Differential Mobility Analyzer, support the conclusion that ammonium and sulfate are primary components of these newly formed particles.
Aerosol organic carbon to black carbon ratios: Analysis of published data and implications for climate forcing
Authors: Novakov T. , Menon S. , Kirchstetter T. W. , Koch D. , Hansen J. E.
Published: November 2005

Measurements of organic carbon (OC) and black carbon (BC) concentrations over a variety of locations worldwide have been analyzed to infer the spatial distributions of the ratios of OC to BC. Since these ratios determine the relative amounts of scattering and absorption, they are often used to estimate the radiative forcing due to aerosols. An artifact in the protocol for filter measurements of OC has led to widespread overestimates of the ratio of OC to BC in atmospheric aerosols. We developed a criterion to correct for this artifact and analyze corrected OC to BC ratios. The OC to BC ratios, ranging from 1.3 to 2.4, appear relatively constant and are generally unaffected by seasonality, sources, or technology changes, at the locations considered here. The ratios compare well with emission inventories over Europe and China but are a factor of 2 lower in other regions. The reduced estimate for OC/BC in aerosols strengthens the argument that reduction of soot emissions maybe a useful approach to slow global warming.
A simple TOPMODEL‐based runoff parameterization (SIMTOP) for use in global climate models
Authors: Niu Guo‐Yue , Yang Zong‐Liang , Dickinson Robert E. , Gulden Lindsey E.
Published: November 2005

This paper develops a simple TOPMODEL‐based runoff parameterization (hereinafter SIMTOP) for use in global climate models (GCMs) that improves the runoff production and the partitioning of runoff between surface and subsurface components. SIMTOP simplifies the TOPMODEL runoff formulations in two ways: (1) SIMTOP represents the discrete distribution of the topographic index as an exponential function, not as a three‐parameter gamma distribution; this change improves the parameterization of the fractional saturated area, especially in mountainous regions. (2) SIMTOP treats subsurface runoff as a product of an exponential function of the water table depth and a single coefficient, not as a product of several parameters that depend on topography and soil properties; this change facilitates applying TOPMODEL‐based runoff schemes on global scale. SIMTOP is incorporated into the National Center for Atmospheric Research (NCAR) Community Land Model version 2.0 (CLM 2.0). SIMTOP is validated at a watershed scale using data from the Sleepers River watershed in Vermont, USA. It is also validated on a global scale using the monthly runoff data from the University of New Hampshire Global Runoff Data Center (UNH‐GRDC). SIMTOP performs favorably when compared to the baseline runoff formulation used in CLM2.0. Realistic simulations can be obtained using two distinct saturated hydraulic conductivity (Ksat) profiles. These profiles include (1) exponential decay of Ksat with depth (as is typically done in TOPMODEL‐based runoff schemes) and (2) the definition of Ksat using the soil texture profile data (as is typically done in climate models) and the concordant reduction of the gravitational drainage from the bottom of the soil column.