bluuebunny/crossref_metadata_2025 huggingface dataset:
COMPUTATIONAL STUDY OF UNIMOLECULAR DECOMPOSITION MECHANISM OF RDX EXPLOSIVE
Authors: LIU MIN HSIEN , ZHENG GEN FA
Published: June 2007

This study investigated the RDX (1,3,5-Trinitro-1,3,5-triazine) molecule to elucidate its possible decomposition species and the corresponding energies by performing the density-functional theory (DFT) calculations. Reasonable decomposition mechanisms are proposed based on the bond energy calculated using the differential overlap (INDO) program, which yields the weakest bonding site for reference and determines the site of easy cleavage. Computational results indicate that the activation energy of direct cis-form HONO elimination is lower than that of direct trans-form HONO elimination and that of a two-stage elimination of two forms of HONO ( N – N bond fission combined with C – H bond breaking) in the initial decomposition step, which are 213.9 kJ/mol and 93.8–101.8 kJ/mol, respectively. Two possible pathways are proposed; (1) N – N bond homolytic cleavage followed by elimination of cis-form HONO, and (2) N – N bond homolytic cleavage followed by elimination of trans-form HONO.
THEORETICAL INVESTIGATION ON THE ACTIVATION OF ETHANE VIA NICKEL ATOM CATALYSIS
Authors: LI LAI-CAI , LIU JUN-LING , SHANG JING , WANG XIN , WONG NING-BEW
Published: June 2007

The reaction mechanism of the activation of ethane by nickel atom has been investigated by density functional theory (DFT). The geometries and vibration frequencies of reactants, intermediates, transition states and products have been calculated at the B3LYP/6-311 + +G(d, p) level. Two main pathways, C – C bond activation and C – H bond activation, are identified. In former channel, the rate-limiting step is found to be hydrogen-transferring step with a high barrier of 227 kJ · mol-1. In the C – H bond activation pathway, the second hydrogen-transferring step is the rate-determining step of the whole reaction. The barrier of the step is 71 kJ · mol-1. Our results show that the studied reaction would undergo along C – H bond activation pathway to form the products H 2 molecule and Ni ⋯ethene complex. The present theoretical work indicates that Ni atom is more active than Ni + cation in activating ethane.
THEORETICAL AND EXPERIMENTAL STUDY OF ELECTRICAL AND ELECTROCHEMICAL PROPERTIES OF (E)-3-(4, 5-DIHYDROXY-2-(PHENYLSULPHONYL) PHENYL) ACRYLIC ACID AS A NEW CAFFEIC ACID DERIVATIVE
Authors: RIAHI SIAVASH , GANJALI MOHAMMAD REZA , MOGHADDAM ABDOLMAJID BAYANDORI , NOROUZI PARVIZ
Published: June 2007

The electrode potentials of (E)-3-(4,5-dihydroxy-2-(phenylsulphonyl) phenyl) acrylic acid (DPA), as a new caffeic acid derivative, in aqueous solution have been calculated. DPA has two geometric structures, cis and trans. Since the cis structure of caffeic is unstable, it cannot be found in nature, but in this research, its electrode potential have been calculated theoretically. The calculations have been performed using ab initio molecular orbital calculations (HF), and density functional theory (DFT) with the inclusion of entropic and thermochemical corrections to yield free energies of redox reactions. The electrode potential was also obtained experimentally by means of an electrochemical technique (cyclic voltammetry) and it was 335 mV for trans structure. The theoretical and experimental values for the electrode potential of the studied molecule are in excellent agreement. Geometric parameters and vibrational frequencies values of DPA and (2E)-3-(3,4-dioxo-6-(phenylsulfonyl) cyclohexa-1,5-dienyl)acrylic acid (DPDA is the oxidized form of DPA), were computed using same methods. The calculated IR spectrum of DPA used for the assignment of IR frequencies was observed in the experimental FT-IR spectrum. Correlations between theoretical and experimental vibrational frequencies of DPA molecule were 0.996. The agreement mutually verifies the accuracy of the experimental method and the validity of the applied mathematical model.
THE THEORY OF REACTION-DIFFUSION PROCESSES AT CYLINDRICAL ULTRAMICROELECTRODES
Authors: RAHAMATHUNISSA G. , BASHA C. A. , RAJENDRAN L.
Published: June 2007

The transient chronoamperometric current for a catalytic reaction mechanism (EC' reaction) at cylindrical ultramicroelectrodes is derived using Danckwerts' expression for short time and slow reaction rate. The transient current for an EC' reaction at cylindrical microelectrodes for all time and all reaction rate is also reported.
RADIOACTIVE WASTE MANAGEMENT IN HUNGARY: CHANGING APPROACHES AND CONFLICTS
Authors: VARI ANNA , FERENCZ ZOLTAN
Published: June 2007

One of the most interesting paradoxes of the application of nuclear energy in Hungary is that although the building, operation, and even the recent lifetime extension of the Paks nuclear power plant has not faced significant social opposition, attempts for siting radioactive waste disposal facilities have been accompanied by a number of social conflicts. The paper reviews the history of radioactive waste management in Hungary from the 1970s until recently. It is found that since the political transition of 1990, top-down technocratic approaches to facility siting have been replaced by the so-called "market approach", which put a strong emphasis on host community support. Most important elements of the latter approach include public information and the provision of generous financial compensation/incentives for host and neighbouring communities. However, analysis of recent Hungarian siting cases shows the weaknesses of the pure market approach, e.g., the lack of transparency and openness regarding national strategies, the lack of accountability, and the focus on financial incentives rather than sustainable development issues.
Pancreatitis following Olanzapine Therapy: A Report of Three Cases
Authors: Kerr Thomas A. , Jonnalagadda Sreenivasa , Prakash Chandra , Azar Riad
Published: June 2007

Context: Atypical antipsychotic agents (clozapine, olanzapine) have been linked to metabolic effects and acute pancreatitis. Case Report: We reviewed the inpatient and outpatient records of three patients who developed acute pancreatitis while being treated with olanzapine. The mean age of the patients was 37.7 years (range 18–54 years, 2 female, 1 male). No alternative cause of acute pancreatitis was found in two of the three patients. In the remaining patient, olanzapine may have contributed to acute pancreatitis in the setting of hypertriglyceridemia. Olanzapine was discontinued in all instances. Over a mean follow-up of 14 months, one patient has had a relapsing course, but the remaining two patients have been symptom free without recurrence of acute pancreatitis. Conclusions: Our case series adds further support to the potential link between olanzapine use and acute pancreatitis. Close monitoring of metabolic parameters is suggested in patients treated with olanzapine. Alternative antipsychotic agents should be considered in patients at high risk for pancreatitis.
Immune Modulation after Total Hip Surgery
Authors: Bastian D. , Sun J. , Danckert Krohn C. , Reikerås O.
Published: June 2007

Background: Major trauma affects the immune system, and immunosuppression may render the patients susceptible to septic complications. The purpose of this study was to investigate lipopolysaccharide (LPS)-induced releases of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in whole blood in patients undergoing total hip replacement. Methods: Seven patients (6 females) who underwent elective total hip replacement were included. Ex vivo LPS-induced releases of TNF-α and IL-6 were measured in a whole blood assay at days 1, 6, 9 and 12 postoperatively, using low- and high-dose LPS incubation. At the same time, white blood cell counts were analyzed. Results: The amount of TNF-α release was significantly reduced at days 6 and 12. Compared to monocyte counts, TNF-α release was significantly decreased also at day 9 in low- and high-dose LPS stimulation. IL-6 in plasma was significantly increased at day 1 and normalized thereafter. There were no differences in LPS-induced IL-6 levels compared to the levels before surgery. Conclusion: This in vivo/ex vivo study shows a reduced capacity of whole blood to release LPS-induced TNF-α at day 6 through to day 12 after major orthopedic surgery. Attenuated TNF-α release may contribute to an increased postoperative susceptibility to gram-negative sepsis.
Topo-Proteomic in situ Analysis of Psoriatic Plaque under Efalizumab Treatment
Authors: Bonnekoh B. , Pommer A.J. , Böckelmann R. , Hofmeister H. , Philipsen L. , Gollnick H.
Published: June 2007

In a pilot study 6 psoriasis patients were treated over 12 weeks with efalizumab targeting the CD11a subunit of LFA-1. The treatment was well tolerated. Five of these patients proved to be responders with an average decrease in psoriasis area and severity index (PASI) from 21.3 ± 5.4 (day 0) to 3.9 ± 0.6 (week 12). The nonresponder was subsequently successfully treated with cyclosporin. Skin biopsies were taken before and after efalizumab treatment and subjected to Multi-Epitope Ligand Cartography (MELC) robot microscopy. A MELC library of 46 antibodies including FITC-labeled efalizumab was chosen focusing upon inflammatory epitopes. Quantification of marker expression was performed using a special adaptation to the needs of skin tissue in terms of pixel events normalized to a standardized horizontal skin width of 100 µm. The before-versus-after comparison for the responders revealed at the ‘single epitope level’ of MELC analysis a significant decrease (p < 0.05) in epidermal thickness (represented by pan-cytokeratin, CD71, CD138), of the expression of common leukocyte antigen (CD45), T-cell markers (CD2, CD4, CD8, CD45R0), CD11a, efalizumab binding site (EfaBS), and CD58. At the ‘EfaBS-centered, double colocation level’ a corresponding decrease was observed for CD2, CD3, CD4, CD8, CD11a, CD13, CD26, CD44, CD45, CD45R0, CD54, CD62L, HLA-DR, and TIA-1. MELC analysis at the ‘multicombinatorial level’ revealed predominant combinatorial molecular phenotype (CMP) motifs, which showed an efalizumab treatment-dependent significant decrease. These CMP motifs were defined as toponomic combinations of lead markers for (i) leukocytes in general (CD45), (ii) T cells (CD2, CD3, CD4, CD45R0, CD45RA), (iii) macrophages (CD68), (iv) cell activation (CD13, CD26, HLA-DR), and (v) cell adhesion (CD11a, EfaBS). Thirty-five of the most relevant 50 CMP motifs were directly related to the T-cell type. A descriptive statistical analysis of the nonresponder before treatment showed a below-responder range degree of expression for CD4, CD8, CD44 (H-CAM), CD56, CD62L, HLA-DQ, and also for these epitopes in colocation with EfaBS. In the nonresponder and before treatment we observed an above-responder range degree of expression for CD54 (ICAM-1) as LFA-1 ligand. In conclusion, the topo-proteomic data provide new diversified insights into the pleiotropic cellular dynamics in psoriatic skin lesions under effective efalizumab treatment. Moreover, the data may be relevant to the future development of possible strategies for individual prediction of efalizumab treatment response or nonresponse.
Hypoxic Regulation of Glucose Transport, Anaerobic Metabolism and Angiogenesis in Cancer: Novel Pathways and Targets for Anticancer Therapeutics
Authors: Airley Rachel E. , Mobasheri Ali
Published: June 2007

Cancer cells require a steady source of metabolic energy in order to continue their uncontrolled growth and proliferation. Accelerated glycolysis is one of the biochemical characteristics of cancer cells. Recent work indicates that glucose transport and metabolism are essential for the posttreatment survival of tumor cells, leading to poor prognosis. Glycolytic breakdown of glucose is preceded by the transport of glucose across the cell membrane, a rate-limiting process mediated by facilitative glucose transporter proteins belonging to the facilitative glucose transporter/solute carrier GLUT/SLC2A family. Tumors frequently show overexpression of GLUTs, especially the hypoxia-responsive GLUT1 and GLUT3 proteins. There are also studies that have reported associations between GLUT expression and proliferative indices, whilst others suggest that GLUT expression may be of prognostic significance. In this article we revisit Warburg’s original hypothesis and review the recent clinical and basic research on the expression of GLUT family members in human cancers and in cell lines derived from human tumors. We also explore the links between hypoxia-induced genes, glucose transporters and angiogenic factors. Hypoxic tumors are significantly more malignant, metastatic, radio- and chemoresistant and have a poor prognosis. With the discovery the oxygen-sensitive transcription factor hypoxia-inducible factor (HIF-1) has come a new understanding of the molecular link between hypoxia and deregulated glucose metabolism. HIF-1 induces a number of genes integral to angiogenesis, e.g. vascular endothelial growth factor (VEGF), a process intimately involved with metastatic spread. This knowledge may enhance existing chemotherapeutic strategies so that treatment can be more rationally applied and personalized for cancer patients.
Cognitive Impairment in Alzheimer’s Disease Is Modified by APOE Genotype
Authors: van der Vlies Annelies E. , Pijnenburg Yolande A.L. , Koene Teddy , Klein Martin , Kok Astrid , Scheltens Philip , van der Flier Wiesje M.
Published: June 2007

Aim: We examined whether impairment in specific cognitive domains in Alzheimer’s disease (AD) differed according to APOE genotype and age at onset. Methods: Cognitive functions of 229 consecutive AD patients were assessed using Visual Association Test (VAT), Memory Impairment Screen+ (MIS+), VAT object naming, fluency test and Trail Making Test (TMT). Dementia severity was assessed using MMSE. ANOVAs were performed with APOE genotype and age at onset as independent variables and sex, education and MMSE as covariates. Results: 28% of patients were APOE Ε4-negative, 58% heterozygous and 14% homozygous. A significant association between APOE genotype and VAT and MIS+ was found when correcting for sex and education. An interaction effect between APOE genotype and age at onset on VAT and VAT object naming was found, with young carriers performing worse than young noncarriers. By contrast, when additionally correcting for MMSE, a significant association between APOE genotype and VAT object naming, TMT-A and TMT-B was found, with noncarriers performing worse than carriers. Conclusion: Memory was more impaired among APOE Ε4 carriers than among noncarriers. By contrast, naming, executive functions and mental speed were more impaired among APOE Ε4 noncarriers. This suggests that the APOE genotype modifies the clinical phenotype in terms of cognitive impairment in AD.
SCN4B
-Encoded Sodium Channel β4 Subunit in Congenital Long-QT Syndrome
Authors: Medeiros-Domingo Argelia , Kaku Toshihiko , Tester David J. , Iturralde-Torres Pedro , Itty Ajit , Ye Bin , Valdivia Carmen , Ueda Kazuo , Canizales-Quinteros Samuel , Tusié-Luna Maria Teresa , Makielski Jonathan C. , Ackerman Michael J.
Published: June 2007

Background—

Congenital long-QT syndrome (LQTS) is potentially lethal secondary to malignant ventricular arrhythmias and is caused predominantly by mutations in genes that encode cardiac ion channels. Nearly 25% of patients remain without a genetic diagnosis, and genes that encode cardiac channel regulatory proteins represent attractive candidates. Voltage-gated sodium channels have a pore-forming α-subunit associated with 1 or more auxiliary β-subunits. Four different β-subunits have been described. All are detectable in cardiac tissue, but none have yet been linked to any heritable arrhythmia syndrome.

Methods and Results—

We present a case of a 21-month-old Mexican-mestizo female with intermittent 2:1 atrioventricular block and a corrected QT interval of 712 ms. Comprehensive open reading frame/splice mutational analysis of the 9 established LQTS-susceptibility genes proved negative, and complete mutational analysis of the 4 Na
vβ
-subunits revealed a L179F (C535T) missense mutation in
SCN4B
that cosegregated properly throughout a 3-generation pedigree and was absent in 800 reference alleles. After this discovery,
SCN4B
was analyzed in 262 genotype-negative LQTS patients (96% white), but no further mutations were found. L179F was engineered by site-directed mutagenesis and heterologously expressed in HEK293 cells that contained the stably expressed
SCN5A
-encoded sodium channel α-subunit (hNa
V
1.5). Compared with the wild-type, L179F-β4 caused an 8-fold (compared with
SCN5A
alone) and 3-fold (compared with
SCN5A
+ WT-β4) increase in late sodium current consistent with the molecular/electrophysiological phenotype previously shown for LQTS-associated mutations.

Conclusions—

We provide the seminal report of
SCN4B
-encoded Na
vβ
4 as a novel LQT3-susceptibility gene.
Molecular Imaging of Inflammation in Atherosclerosis With Targeted Ultrasound Detection of Vascular Cell Adhesion Molecule-1
Authors: Kaufmann Beat A. , Sanders John M. , Davis Christopher , Xie Aris , Aldred Patrick , Sarembock Ian J. , Lindner Jonathan R.
Published: June 2007

Background—

The ability to image vascular inflammatory responses may allow early diagnosis and treatment of atherosclerosis. We hypothesized that molecular imaging of vascular cell adhesion molecule-1 (VCAM-1) expression with contrast-enhanced ultrasound (CEU) could be used for this purpose.

Methods and Results—

Attachment of VCAM-1–targeted and control microbubbles to cultured endothelial cells was assessed in a flow chamber at variable shear stress (0.5 to 12.0 dynes/cm
2
). Microbubble attachment to aortic plaque was determined by en face microscopy of the thoracic aorta 10 minutes after intravenous injection in wild-type or apolipoprotein E–deficient mice on either chow or hypercholesterolemic diet. CEU molecular imaging of the thoracic aorta 10 minutes after intravenous microbubble injection was performed for the same animal groups. VCAM-1–targeted but not control microbubbles attached to cultured endothelial cells, although firm attachment at the highest shear rates (8 to 12 dynes/cm
2
) occurred only in pulsatile flow conditions. Aortic attachment of microbubbles and targeted CEU signal was very low in control wild-type mice on chow diet. Aortic attachment of microbubbles and CEU signal for VCAM-1–targeted microbubbles differed between treatment groups according to extent of VCAM-1–positive plaque formation (median CEU videointensity, 1.8 [95% CI, 1.2 to 1.7], 3.7 [95% CI, 2.9 to 7.3], 6.8 [95% CI, 3.9 to 7.6], and 11.2 [95% CI, 8.5 to 16.0] for wild-type mice on chow and hypercholesterolemic diet and for apolipoprotein E–deficient mice on chow and hypercholesterolemic diet, respectively;
P
<0.001).

Conclusions—

CEU molecular imaging of VCAM-1 is capable of rapidly quantifying vascular inflammatory changes that occur in different stages of atherosclerosis. This method may be potentially useful for early risk stratification according to inflammatory phenotype.
Nitinol Stent Implantation Versus Percutaneous Transluminal Angioplasty in Superficial Femoral Artery Lesions up to 10 cm in Length
Authors: Krankenberg Hans , Schlüter Michael , Steinkamp Hermann J. , Bürgelin Karlheinz , Scheinert Dierk , Schulte Karl-Ludwig , Minar Erich , Peeters Patrick , Bosiers Marc , Tepe Gunnar , Reimers Bernhard , Mahler Felix , Tübler Thilo , Zeller Thomas
Published: June 2007

Background—

Endoluminal treatment of superficial femoral artery lesions is a matter of controversy. The present study was designed to investigate the impact of nitinol stenting of superficial femoral artery lesions with a maximum length of 10 cm on restenosis and clinical outcomes at 1 year.

Methods and Results—

Two hundred forty-four patients (168 men; 66±9 years) with a single superficial femoral artery lesion and chronic limb ischemia were randomized to implantation of a single Bard Luminexx 3 stent (123 patients) or stand-alone percutaneous transluminal angioplasty (PTA) (121 patients). Mean lesion length was 45 mm. Technical success (residual stenosis <50% for PTA, <30% for stenting) was achieved in 96 patients assigned to PTA (79%) and 117 patients assigned to stenting (95%); 13 PTA group patients (11%) “crossed over” to stenting. At 1 year, the primary end point of ultrasound-assessed binary restenosis was reached in 39 of 101 PTA group patients (38.6%) and 32 of 101 stent group patients (31.7%; absolute treatment difference, −6.9%; 95% CI, −19.7% to 6.2%;
P
=0.377). Target lesion revascularization rates at 1 year were 18.3% and 14.9%, respectively (absolute treatment difference, −3.3%; 95% CI, −13.0% to 6.4%;
P
=0.595). No statistically significant difference between treatment groups was observed at 12 months in the improvement by at least 1 Rutherford category of peripheral arterial disease.

Conclusions—

In the present study of patients with short superficial femoral artery lesions, the hypothesized absolute difference of 20% in binary restenosis at 1 year between the implantation of a single Luminexx nitinol stent and stand-alone PTA could not be demonstrated. A smaller difference requiring a larger trial might have been missed.
Comparison of the Captopril and the Saline Infusion Test for Excluding Aldosterone-Producing Adenoma
Authors: Rossi Gian Paolo , Belfiore Anna , Bernini Giampaolo , Desideri Giovambattista , Fabris Bruno , Ferri Claudio , Giacchetti Gilberta , Letizia Claudio , Maccario Mauro , Mallamaci Francesca , Mannelli Massimo , Palumbo Gaetana , Rizzoni Damiano , Rossi Ermanno , Agabiti-Rosei Enrico , Pessina Achille C. , Mantero Franco
Published: June 2007

We performed a prospective head-to-head comparison of the accuracy of the captopril test (CAPT) and the saline infusion test (SAL) for confirming primary aldosteronism due to an aldosterone-producing adenoma (APA) in patients with different sodium intake. A total of 317 (26.9%) of the 1125 patients screened in the Primary Aldosteronism Prevalence in Italy Study underwent both CAPT and SAL. They were composed of the patients with a high aldosterone/renin ratio baseline and 1 every 4 patients without such criterion. The accuracy of post-CAPT or post-SAL plasma aldosterone values for diagnosing APA was estimated with the area under the receiver operator characteristics curves. Primary aldosteronism was found in 120 patients, of which 46 had an APA. No untoward effect occurred with either test. The area under the receiver operator characteristics curve of plasma aldosterone for both tests was higher (
P
<0.0001) than that under the diagonal, but the between-test difference was borderline significant (
P
=0.054). The optimal aldosterone cutoff value for identifying APA was 13.9 and 6.75 ng/dL for the CAPT and SAL, respectively. Even at these cutoffs, sensitivity and specificity were moderate because of overlap of values between patients with and without APA. When examined in relation to sodium intake, the accuracy of the SAL surpassed that of the CAPT in the patients with a sodium intake ≤130 mEq per day; this difference waned at a higher Na
+
intake. Thus, both the CAPT and the SAL are safe and moderately accurate for excluding APA; at a sodium intake >7.6 g per day, the SAL offers no advantage over the easier-to-perform CAPT.
Escape from the State of Nature: Authority and Hierarchy in World Politics
Authors: Lake David A.
Published: June 2007

Despite increasing attention, scholars lack the analytic tools necessary to understand international hierarchy and its consequences for politics and policy. This is especially true for the informal hierarchies now found in world affairs. Rooted in a formal-legal tradition, international relations scholars almost universally assume that the international system is a realm of anarchy. Although the fact of anarchy remains a truism for the system as a whole, it is a fallacy of division to infer that all relationships within that system are anarchic. Building on an alternative view of relational authority and recent research on the practice of sovereignty, a new conception of international hierarchy is developed that varies along two continua defined by security and economic relations. This construct is operationalized and validated, and then tested in a large-nstudy of the effects of international hierarchy on the defense effort of countries. The principal finding is that states in hierarchical relationships spend significantly less on defense relative to gross domestic product than states not in such relationships. In short, hierarchy matters and subordination pays; states appear to trade some portion of their sovereignty for protection from external security threats.
Illicit Activity and Proliferation: North Korean Smuggling Networks
Authors: Chestnut Sheena
Published: June 2007

Since public disclosure by the Democratic People's Republic of Korea (DPRK) of its uranium enrichment program in 2002 and the subsequent restarting of its plutonium reactor, policymakers and academics have expressed concern that the DPRK will one day export nuclear material or components. An examination of North Korea's involvement in nonnuclear criminal activities shows that the DPRK has established sophisticated transnational smuggling networks, some of which involve terrorist groups and others that have been able to distribute counterfeit currency and goods on U.S. territory. These networks provide North Korea with a significant amount of much-needed hard currency, but the DPRK regime's control over them has decreased over time. These developments suggest that North Korea has both the means and motivation for exporting nuclear material, and that concerns over nuclear export from the DPRK, authorized or not, are well founded. When placed in the context of the global nuclear black market, the North Korea case suggests that criminal networks are likely to play an increased role in future proliferation. In addition, it raises the concern that proliferation conducted through illicit networks will not always be well controlled by the supplier state. It is therefore imperative to track and curtail illicit networks not only because of the costs they impose, but also because of the deterrent value of countersmuggling efforts. New strategies that integrate law enforcement, counterproliferation, and nonproliferation tools are likely to have the greatest success in addressing the risks posed by illicit proliferation networks.
Supplement to State of the Climate in 2006
Authors: Arguez A.
Published: June 2007

The State of the Climate in 2006 report summarizes the year's weather and climate conditions, both globally and regionally. In addition, the year is placed into a long-term climatological context. Furthermore, notable events are also discussed.

Overall global temperatures were fifth or sixth warmest on record, depending on the dataset, continuing an upward trend in temperatures. Many countries and regions experienced their record warmest year (or tied for warmest), including Spain, the Netherlands, the United Kingdom, and China, as well as parts of Australia and Canada. In many regions, the warmth in 2006 is statistically indistinguishable from the record warmth in 1998. However, 1998 was influenced by the unprecedented warming associated with the record 1997/98 El Niño, whereas 2006 was marked by a 2005/06 La Niña that transitioned into a weak-to-moderate 2006/07 El Niño.

Consistent with the warming, sea ice extent in both polar regions reached record or near-record minima. In addition, Antarctic ozone concentrations reached an all-time minimum. Also, carbon dioxide measurements increased in the atmosphere by 2.3 parts per million (ppm) in 2006 to reach a global average of 381.1 ppm.

In the global oceans, sea levels were above average for ∼80% of the ocean. The global mean sea level anomaly change of +6 mm from 2005 was the highest increase since the altimeter record began in 1993. Relative sea level change was also the highest ever recorded. Significant heat flux and current anomalies were observed in the regions of the 2006 El Niño and Indian Ocean dipole mode event.

Despite the warmth around the globe, tropical cyclone counts were near average. However, Tropical Cyclone Larry made landfall in northern Australia as one of the most intense storms in decades. Following the record Atlantic hurricane season of 2005, the 2006 season was very quiet.
Did the Thermocline Deepen in the California Current after the 1976/77 Climate Regime Shift?
Authors: Kim Hey-Jin , Miller Arthur J.
Published: June 2007

The 55-yr California Cooperative Oceanic Fisheries Investigations (CalCOFI) dataset in the southern California Current reveals a significant surface-intensified warming and stratification (buoyancy frequency) change across the 1976/77 climate regime shift. However, the average depth of the thermocline, defined as the maximum gradient of temperature, did not change significantly across the regime shift. The maximum-gradient criterion for thermocline depth may be more appropriate than following an isotherm because the isotherm necessarily deepens in the presence of surface-intensified warming. As the surface heating changed the strength of stratification, it also changed the slope of the nitrate–temperature relation for the middepth waters (roughly 30–200 m). Thus, the quality of upwelled water may have been fundamentally altered after the shift.
Simulated Variability of the Arctic Ocean Freshwater Balance 1948–2001
Authors: Köberle Cornelia , Gerdes Rüdiger
Published: June 2007

The Arctic Ocean freshwater balance over the period 1948–2001 is examined using results from a hindcast simulation with an ocean–sea ice model of the Atlantic and Arctic Oceans. Atmospheric forcing is taken from the NCEP–NCAR reanalysis and different terrestrial freshwater sources as well as the Bering Strait throughflow are specified as constant seasonal cycles. The long-term variability of the Arctic Ocean liquid freshwater content is determined by the variability of lateral exchanges with the subpolar seas. Surface freshwater flux variability is dominated by the thermodynamic growth of sea ice. This component of the freshwater balance has larger variability at interannual frequencies. The Arctic Ocean liquid freshwater content was at a maximum in the middle of the 1960s. Extremely low liquid freshwater export through Fram Strait caused this maximum in the freshwater content. The low export rate was related to weak volume transports in the East Greenland Current. Low volume transports were forced by a reduction in sea surface height across Fram Strait, triggered by anomalous meltwater from Barents Sea ice export that was carried toward Fram Strait with the West Spitzbergen Current. After the 1960s maximum liquid freshwater content, the Arctic Ocean gradually returned to an equilibrium between export through the passages toward the Atlantic and the freshwater sources.
Causes of Changes in the Denmark Strait Overflow
Authors: Köhl Armin , Käse Rolf H. , Stammer Detlef , Serra Nuno
Published: June 2007

The warming Nordic seas potentially tend to decrease the overflow across the Greenland–Iceland–Scotland Ridge (GISR) system. Recent observations by Macrander et al. document a significant drop in the intensity of outflowing Denmark Strait Overflow Water of more than 20% over 3 yr and a simultaneous increase in the temperature of the bottom layers of more than 0.4°C. A simulation of the exchange across the GISR with a regional ocean circulation model is used here to identify possible mechanisms that control changes in the Denmark Strait overflow and its relations to changed forcing condition. On seasonal and longer time scales, the authors establish links of the overflow anomalies to a decreasing capacity of the dense water reservoir caused by a change of circulation pattern north of the sill. On annual and shorter time scales, the wind stress curl around Iceland determines the barotropic circulation around the island and thus the barotropic flow through Denmark Strait. For the overlapping time scales, the barotropic and overflow component interactively determine transport variations. Last, a relation between sea surface height and reservoir height changes upstream of the sill is used to predict the overflow variability from altimeter data. Estimated changes are in agreement with other recent transport estimates based on current-meter arrays.
Ocean Currents and Sea Surface Heights Estimated across the West Florida Shelf
Authors: Liu Yonggang , Weisberg Robert H.
Published: June 2007

The across-shelf structures of the ocean circulation and the associated sea surface height (SSH) variability are examined on the west Florida shelf (WFS) for the 3-yr interval from September 1998 to December 2001. Five sets of characteristic circulation patterns are extracted from 2-day, low-pass-filtered data using the self-organizing map: extreme upwelling and downwelling structures with strong currents, asymmetric upwelling and downwelling structures with moderate currents, and a set of transitional structures with weak currents. The temporal variations of these structures are coherent with the local winds on synoptic weather time scales. On seasonal time scales they are related to both the local winds and the water density variations. The circulation is predominantly upwelling during autumn to spring months (October–April) and downwelling during summer months (June–September). Coastal sea level fluctuations are related to both the dynamical responses of the inner shelf circulation to meteorological forcing and the offshore SSH. On long time scales, the offshore SSH variations appear to dominate, whereas on synoptic weather time scales, the inner shelf wind-driven circulation responses are largest. The across-shelf distribution of SSH is estimated from the velocity, hydrography, wind, and coastal sea level data, and the results are compared with satellite altimetry data, thereby providing a means for calibrating satellite altimetry on the shelf.
Real-Time Forecasting of Snowfall Using a Neural Network
Authors: Roebber Paul J. , Butt Melissa R. , Reinke Sarah J. , Grafenauer Thomas J.
Published: June 2007

A set of 53 snowfall reports was collected in real time from the 2004/05 and 2005/06 cold seasons (November–March). Three snowfall-amount forecast methods were tested: neural network, surface-temperature-based 676-USDT table, and climatological snow ratio. Standard verification methods (mean, median, bias, and root-mean-square error) and a new method that places the forecasts in the context of municipal snow removal, and introduces the concept of forecast credibility, are used. Results suggest that the neural network method performs best for individual events, owing in part to the inverse relationship between melted liquid equivalent and snow ratio; hence, the ongoing difficulty of producing accurate forecasts of melted equivalent precipitation (a problem in all seasons) is compensated for rather than amplified when converting to snowfall amounts. This analysis should be extended to a larger selection of reports, which is anticipated in conjunction with efforts currently ongoing at the National Oceanic and Atmospheric Administration’s Hydrometeorological Prediction Center.
The New French Operational Radar Rainfall Product. Part I: Methodology
Authors: Tabary P.
Published: June 2007

A new radar-based rainfall product has been developed at Météo-France and is currently being deployed within the French operational Application Radar à la Météorologie Infra-Synoptique (ARAMIS) radar network. The rainfall product is based entirely on radar data and comprises the following successive processing steps: 1) dynamic identification of ground clutter based on the pulse-to-pulse fluctuation of the radar signal, 2) reflectivity-to-rain-rate conversion using the Marshall–Palmer Z–R relationship, 3) correction for partial beam blocking using numerical simulations of the interaction between the radar wave and the terrain, 4) correction for vertical profile of reflectivity (VPR) effects based on ratio curves and a priori climatology-based VPR candidates, 5) correction for nonsimultaneity of radar measurements by making use of a cross-correlation advection field, 6) weighted linear combination of the corrected reflectivity measurements gathered at the various elevation angles of the volume coverage pattern, and 7) production of a 5-min rain accumulation using the advection field to mitigate undersampling effects. In addition to the final Cartesian, 512 km × 512 km, 1 km2 in resolution, radar rainfall product, a map of quality indexes is automatically generated that allows for assessing empirically the accuracy of the estimation. This new product has been validated using 27 episodes observed during the autumns of 2002 and 2003 and the winter of 2005 by three S-band radars of the network. This paper is entirely devoted to the description of the methodology.
Mountain Wave Signatures in MODIS 6.7-μm Imagery and Their Relation to Pilot Reports of Turbulence
Authors: Uhlenbrock N. L. , Bedka K. M. , Feltz W. F. , Ackerman S. A.
Published: June 2007

A technique for nowcasting turbulent mountain waves over the Front Range of the state of Colorado is investigated using Moderate Resolution Imaging Spectroradiometer (MODIS) water vapor (6.7 μm) channel imagery. Pilot reports of turbulence were examined to determine the probability of turbulence occurring when wave features were observed in the satellite imagery. Analysis of MODIS water vapor imagery indicated that mountain wave signatures were present for approximately 25% of the days during 2004. Approximately 75% of the severely turbulent days, as indicated by pilot reports, had wave signatures in the water vapor imagery. The wave signatures on the severely turbulent days had different characteristics in the imagery than the signatures on days that were less turbulent. The reports of severe turbulence were associated with complex patterns, the appearance of interference, or crossing wave fronts that extended downwind from the mountain ridge for a significant distance. The days that were less turbulent, as reported by pilots, had wave signatures with a simpler pattern, such as linear features orthogonal to the wind flow oriented parallel to one another.
The Warning Decision Support System–Integrated Information
Authors: Lakshmanan Valliappa , Smith Travis , Stumpf Gregory , Hondl Kurt
Published: June 2007

The Warning Decision Support System–Integrated Information (WDSS-II) is the second generation of a system of tools for the analysis, diagnosis, and visualization of remotely sensed weather data. WDSS-II provides a number of automated algorithms that operate on data from multiple radars to provide information with a greater temporal resolution and better spatial coverage than their currently operational counterparts. The individual automated algorithms that have been developed using the WDSS-II infrastructure together yield a forecasting and analysis system providing real-time products useful in severe weather nowcasting. The purposes of the individual algorithms and their relationships to each other are described, as is the method of dissemination of the created products.
A Satellite-Based Fog Detection Scheme Using Screen Air Temperature
Authors: Gultepe I. , Pagowski M. , Reid J.
Published: June 2007

A warm fog detection (air temperature > −5°C) algorithm using a combination of Geostationary Operational Environmental Satellite-12 (GOES-12) observations and screen temperature data based on an operational numerical model has been developed. This algorithm was tested on a large number of daytime cases during the spring and summer of 2004. Results from the scheme were compared with surface observations from four manned Canadian weather stations in Ontario, including Ottawa, Windsor, Sudbury, and Toronto. Initially, when all cases were included, fog detection (hit rate) by the satellite scheme ranged between 0.26 and 0.32. It is suggested that mid- or high-level clouds within the satellite imagery during the observed foggy periods affected the scheme’s performance in detecting surface-level fog for the majority of the cases. When cases with mid- and high-level clouds were removed using model-based screen temperatures, the hit rate ranged between 0.55 and 1.0. With an average false alarm rate of 0.10, the inclusion of model-based sounding values can be seen to improve results from the satellite-based algorithms by an average of 0.42. Average differences between the screen temperature and the surface-observed air temperature were found to be up to 2°C and this can likely account for some discrepancies in detecting fog. Finally, averaging GOES and model data to scales representing single data-point observations likely resulted in some of the failure of the fog algorithm.
Some Aspects of Dense Fog in the Midwestern United States
Authors: Westcott Nancy E.
Published: June 2007

To better understand dense fog events in the midwestern United States, a fog climatology was developed that examines the surface weather conditions at dense fog onset and during dense fog events, in relationship to fog duration. Surface airways hourly observations for the period 1948–96 were examined, focusing primarily on Peoria, Illinois, during the cold season (October–March). Temperature, winds, and visibility at dense fog onset did not prove to be useful in differentiating between short- (1–2 h) and long- (>5 h) duration dense fog events. However, it was found that once dense fog forms, it is more likely to persist if the horizontal visibility is 200 m (1/8 mi) or less and the ceiling height lowers to 30 m (100 ft) or less. Further, dense fog events at Peoria tend to last longer if they are widespread, that is, when many other midwestern surface airways hourly stations also report dense fog. When dense fog develops early in the night to the hours just after midnight, it is more likely to persist than when it develops later in the night or during the day. This was found to be the case for many other midwestern stations as well. Fog events forming earlier in the night may last longer because of the absence of solar insolation upon the fog layer during the night. As longer-duration fogs often become more opaque and more widespread than short-duration events, more time may be required to dissipate fog once the sun has risen. Dense fog onset time and the physical dimensions of the fog events appear to be the best predictors of fog duration considering all types of fog in the Midwest.
Population Influences on Tornado Reports in the United States
Authors: Anderson Christopher J. , Wikle Christopher K. , Zhou Qin , Royle J. Andrew
Published: June 2007

The number of tornadoes reported in the United States is believed to be less than the actual incidence of tornadoes, especially prior to the 1990s, because tornadoes may be undetectable by human witnesses in sparsely populated areas and areas in which obstructions limit the line of sight. A hierarchical Bayesian model is used to simultaneously correct for population-based sampling bias and estimate tornado density using historical tornado report data. The expected result is that F2–F5 compared with F0–F1 tornado reports would vary less with population density. The results agree with this hypothesis for the following population centers: Atlanta, Georgia; Champaign, Illinois; and Des Moines, Iowa. However, the results indicated just the opposite in Oklahoma. It is hypothesized that the result is explained by the misclassification of tornadoes that were worthy of F2–F5 rating but were classified as F0–F1 tornadoes, thereby artificially decreasing the number of F2–F5 and increasing the number of F0–F1 reports in rural Oklahoma.
Short-Range Numerical Weather Prediction Using Time-Lagged Ensembles
Authors: Lu Chungu , Yuan Huiling , Schwartz Barry E. , Benjamin Stanley G.
Published: June 2007

A time-lagged ensemble forecast system is developed using a set of hourly initialized Rapid Update Cycle model deterministic forecasts. Both the ensemble-mean and probabilistic forecasts from this time-lagged ensemble system present a promising improvement in the very short-range weather forecasting of 1–3 h, which may be useful for aviation weather prediction and nowcasting applications. Two approaches have been studied to combine deterministic forecasts with different initialization cycles as the ensemble members. The first method uses a set of equally weighted time-lagged forecasts and produces a forecast by taking the ensemble mean. The second method adopts a multilinear regression approach to select a set of weights for different time-lagged forecasts. It is shown that although both methods improve short-range forecasts, the unequally weighted method provides the best results for all forecast variables at all levels. The time-lagged ensembles also provide a sample of statistics, which can be used to construct probabilistic forecasts.
Pyongyang Sees the Nuke Impasse
Authors: Park Han S.
Published: June 2007

In order to better understand and explain North Korea's foreign policy strategies and tactics on the controversy surrounding the nuclear program, this chapter examines the perceptions held by Pyongyang about the neighbouring counties including the United States, Japan, and South Korea. These perceptions are formulated in accordance with North Korea's perception about itself that is generally constructed based on the principle of Juche (self-reliance) and the political and security environment surrounding the Korean peninsula as perceived by Pyongyang itself. North Korea is an unconventional country if one looks from outside but it is not irrational in that it has pursued its own national interest rather effectively for which security is first and foremost. This chapter provides an explanation of North Korean conducts from the perspective of North Korea's own mind-set.
Development of a Tiny Orientation Estimation Device to Operate under Motion and Magnetic Disturbance
Authors: Harada Tatsuya , Mori Taketoshi , Sato Tomomasa
Published: June 2007

A tiny absolute orientation estimating device equipped with a network function has been developed using accelerometers and magnetometers to estimate gravity and the geomagnetic field, respectively. Because accelerometers measure motion other than gravity, a method has been proposed to eliminate the effect of motion. An estimation method is proposed that excludes the effect of magnetic disturbances. An advantage of this estimation method is that models can be switched according to the environment. Sigma Points Kalman Filters (SPKFs) were evaluated to determine the proper filter for the proposed algorithm. A Square-Root Central Difference Kalman Filter (SR-CDKF) was the best method considering stability, accuracy, and calculation cost. Using simulations and the realized device, the proposed algorithm stably estimated the orientation in the presence of motion and magnetic disturbances.
Fast Ego-motion Estimation with Multi-rate Fusion of Inertial and Vision
Authors: Armesto Leopoldo , Tornero Josep , Vincze Markus
Published: June 2007

This paper presents a tracking system for ego-motion estimation which fuses vision and inertial measurements using EKF and UKF (Extended and Unscented Kalman Filters), where a comparison of their performance has been done. It also considers the multi-rate nature of the sensors: inertial sensing is sampled at a fast sampling frequency while the sampling frequency of vision is lower. the proposed approach uses a constant linear acceleration model and constant angular velocity model based on quaternions, which yields a non-linear model for states and a linear model in measurement equations. Results show that a significant improvement is obtained on the estimation when fusing both measurements with respect to just vision or just inertial measurements. It is also shown that the proposed system can estimate fast-motions even when vision system fails. Moreover, a study of the influence of the noise covariance is also performed, which aims to select their appropriate values at the tuning process. The setup is an end-effector mounted camera, which allow us to pre-define basic rotational and translational motions for validating results.