bluuebunny/crossref_metadata_2025 huggingface dataset:
Thrombocytopenia after hepatic cryotherapy for colorectal metastases: Correlates with hepatocellular injury
Authors: Cozzi Paul J. , Stewart Graham J. , Morris David L.
Published: October 2004

Postoperative thrombocytopenia following hepatic cryotherapy has been well documented and shown to be significantly greater than in control patients who had an identical incision or major laparotomy. Serum aspartate transaminase (AST) levels have been used as a reliable indicator of hepatocellular destruction. This study reviews 65 consecutive hepatic cryotherapy operations. We have excluded all patients who had repeat cryotherapy to lesions (n=6), all who had a colonic or hepatic resection procedure (n=7), all who had tumors other than colorectal metastases (n=5), patients with inadequate data (n=9), and those who were asplenic (n=2). Of the remaining 36 patients, 14 were treated with a single freeze/thaw cycle, 12 were treated with a double freeze/thaw cycle, and 10 were treated with mixed single and double freezes. The most common platelet nadir was day 3 (n=21) followed by day 2 (n=11), with the remaining platelet nadirs being day 1 or 4 (n=4). The percentage fall in platelet count was found to correlate with the rise in day 1 AST level (r2=0.74, least squares linear regression). The double freeze/thaw cycle patients had a significantly greater fall in platelet count (p=0.01, Mann‐Whitney two sample test). Another institution has reported three deaths due to multiple problems, including coagulopathy in patients treated with double freeze/thaw cycle cryotherapy. The conclusions of this study are that a high AST level on day 1 is a good predictor of impending thrombocytopenia, and that double freeze/thaw cycle cryotherapy results in marked thrombocytopenia, which may be responsible for the coagulopathy seen in some of these patients.
Scientiae forum/Models and speculations Pathways for axonal targeting of membrane proteins
Authors: Winckler Bettina
Published: October 2004

Abstract The distribution of proteins to the correct domains of neurons is crucial for neuronal functioning. Here I discuss possible mechanisms underlying sorting to the axonal plasma membrane which differ with respect to the steps providing selectivity for axonal vs. somatodendritic cargo. Selectivity can be executed at one or more than one step, including sorting into distinct carriers in the Golgi, preferential transport along axonal microtubules, fusion with the plasma membrane, and importantly retrieval by endocytosis. A protein might in fact be sorted multiple times at different places to achieve axonal localization.
Differences in unpleasantness induced by experimental pressure pain between patients with fibromyalgia and healthy controls
Authors: Petzke Frank , Harris Richard E. , Williams David A. , Clauw Daniel J. , Gracely Richard H.
Published: October 2004

Pain possesses both sensory and affective dimensions, which are highly correlated yet distinct. Comparison of these dimensions within experimental pain settings has resulted in the construct of relative unpleasantness. Relative unpleasantness is defined as the amount of affective unpleasantness elicited for a given sensory magnitude. The aim of this study was to determine the relationship between affective and sensory components of evoked pain in subjects with fibromyalgia (FM) and healthy controls. Here we show that patients with FM unexpectedly display less relative unpleasantness than healthy controls in response to random noxious pressure stimuli. Relative unpleasantness was not correlated with distress, anxiety, or depression, which were pronounced in the FM group. Clinical pain in patients with FM was perceived to be more unpleasant than the evoked pain stimuli. These results are consistent with the concept that chronic pain may reduce the relative unpleasantness of evoked pain sensations.
Object alternation test—is it sensitive enough to detect cognitive dysfunction in obsessive–compulsive disorder?
Authors: Katrin Kuelz Anne , Riemann Dieter , Zahn Roland , Voderholzer Ulrich
Published: October 2004

A computerized version of the object alternation test (OAT) was employed in unmedicated obsessive–compulsive disorder (OCD) patients and matched healthy controls. OCD patients performed normally on the OAT but scored below controls on a task assessing visuo-spatial working memory. The results challenge the concept of the OAT as a sensitive instrument for orbitofrontal dysfunction in OCD.
What about psychiatrists' attitude to mentally ill people?
Authors: Lauber Christoph , Anthony Marion , Ajdacic-Gross Vladeta , Rössler Wulf
Published: October 2004

Objective

Firstly, to assess and, secondly, to compare experts' and lay attitudes towards community psychiatry and the respective social distance towards mentally ill people.

Method

Comparison of two representative Swiss samples, one comprising of 90 psychiatrists, the other including 786 individuals of the general population.

Results

The psychiatrists' attitude was significantly more positive than that of the general population although both samples have a positive attitude to community psychiatry. The statement that mental health facilities devalue a residential area has revealed most agreement. Psychiatrists and the public do not differ in their social distance to mentally ill people. Among both samples, the level of social distance increases the more the situation described implies ‘social closeness’.

Conclusion

The strategy to use psychiatrists as role models or opinion leaders in anti-stigma campaigns cannot be realised without accompanying actions. Psychiatrists must be aware that their attitudes do not differ from the general public and, thus, they should improve their knowledge about stigma and discrimination towards people with mental illnesses.
Calcium inhibits muscle FBPase and affects its intracellular localization in cardiomyocytes
Authors: Gizak A. , Majkowski M. , Dus D. , Dzugaj A.
Published: October 2004

As our recent investigation revealed, in mammalian heart muscle, fructose 1,6‐bisphosphatase (FBPase) – a key enzyme of glyconeogenesis – is located around the Z‐line, inside cells' nuclei and, as we demonstrate here for the first time, it associates with intercalated discs. Since the degree of association of numerous enzymes with subcellular structures depends on the metabolic state of the cell, we studied the effect of elevated Ca2+ concentration on localization of FBPase in cardiomyocytes. In such conditions, FBPase dissociated from the Z‐line, but no visible effect on FBPase associated with intercalated discs or on the nuclear localization of the enzyme was observed. Additionally, Ca2+ appeared to be a strong inhibitor of muscle FBPase.
Interaction of rat poly(A)‐binding protein with poly(A)‐ and non‐poly(A) sequences is preferentially mediated by RNA recognition motifs 3 + 4
Authors: Mullin Carola , Duning Kerstin , Barnekow Angelika , Richter Dietmar , Kremerskothen Joachim , Mohr Evita
Published: October 2004

Vasopressin (VP) mRNA and the non‐coding BC200 RNA are sorted to neuronal dendrites. Among proteins interacting specifically with both RNAs is the multifunctional poly(A)‐binding protein (PABP) consisting of four RNA recognition motifs (RRMs) and a C‐terminal auxiliary domain. The protein/RNA interaction studies presented here reveal that PABPs association with VP‐ and BC200 RNA is exclusively mediated by RRMs 3 + 4. Quantitative binding studies with PABP deletion mutants demonstrate preferential binding of RRMs 3 + 4 even to poly(A)‐homopolymers, while RRMs 1 + 2 exhibit a lower affinity for those sequences. An optimal interaction with both poly(A)‐ and non‐poly(A) sequences is only achieved by full‐size PABP.
ETS‐1 transcription factor activates the expression of mouse UDP‐Gal:GA2/GM2/GD2/GT2 galactosyltransferase gene
Authors: Raimondi Lina P. , Daniotti Jose L. , Maccioni Hugo J.F.
Published: October 2004

UDP‐Gal:GA2/GM2/GD2/GT2 galactosyltransferase (Gal‐T2) transfers galactose to the terminal N‐acetylgalactosamine of either the neutral glycolipid GA2 or of the gangliosides GM2, GD2 and GT2. Previous studies revealed a tight regulation of Gal‐T2 activity and mRNA expression during development of the rat CNS. Here, we study in PC12 cells the cis‐acting elements involved in the activation of a fragment of 211 bp around the transcription initiation site of the mouse Gal‐T2 promoter. Mutagenesis, competition experiments and functional assays showed that the Ets‐1 transcription factor is involved in the activation of the Gal‐T2 promoter.
Segregation of Nogo66 receptors into lipid rafts in rat brain and inhibition of Nogo66 signaling by cholesterol depletion
Authors: Yu Weiying , Guo Wei , Feng Linyin
Published: October 2004

NogoA, a myelin‐associated component, inhibits neurite outgrowth. Nogo66, a portion of NogoA, binds to Nogo66 receptor (NgR) and induces the inhibitory signaling. LINGO‐1 and p75 neurotrophin receptor (p75), the low‐affinity nerve growth factor receptor, are also required for NogoA signaling. However, signaling mechanisms downstream to Nogo receptor remain poorly understood. Here, we observed that NgR and p75 were colocalized in low‐density membrane raft fractions derived from forebrains and cerebella as well as from cerebellar granule cells. NgR interacted with p75 in lipid rafts. In addition, disruption of lipid rafts by β‐methylcyclodextrin, a cholesterol‐binding reagent, reduced the Nogo66 signaling. Our results suggest an important role of lipid rafts in facilitating the interaction between NgRs and provide insight into mechanisms underlying the inhibition of neurite outgrowth by NogoA.
Effect of interpregnancy interval on birth outcomes: findings from three recent US studies
Authors: Zhu B.‐P.
Published: October 2004

The relationship between interpregnancy interval and adverse birth outcomes (i.e., low birth weight, preterm birth, and small size for gestational age) was examined in three recent studies conducted in Utah and Michigan of the United States. These studies were conducted among different populations, used different study designs (i.e., cross‐sectional and retrospective cohort designs), and addressed several other methodological limitations in the previously published literature. In addition, the data were stratified by, and controlled for, several maternal reproductive risk factors. A J‐shaped relationship between interpregnancy interval and adverse birth outcomes was observed in all three studies. The risk for adverse birth outcomes is lowest when the interpregnancy interval was 18–23 months and increased when the interval departed from 18–23 months. This J‐shaped relationship existed at levels of maternal reproductive risk factors and after these risk factors were controlled for using logistic regression. Based on the consistency of the findings from all three studies, it appears that the J‐shaped relationship between interpregnancy interval and adverse birth outcomes is causal. This information can be used by health care providers and public health programs to counsel and educate women who recently gave births on reducing the risk for adverse birth outcomes by means of appropriate pregnancy spacing.
Is the Delay in Starting Postoperative Radiotherapy a Key Factor in the Outcome of Advanced (T3 and T4) Laryngeal Cancer?
Authors: Marshak Gideon , Rakowsky Erica , Schachter Jacob , Shvero Jacob , Feinmesser Rafael , Sulkes Aaron , Brenner Baruch
Published: October 2004

OBJECTIVE

To identify factors influencing the outcome of postoperative radiotherapy in patients with advanced laryngeal cancer.

DESIGN

The files of 44 patients with advanced laryngeal cancer who were treated by surgery followed by radiotherapy (24 with pT3 and 20 with pT4) were reviewed. Median delay in starting radiotherapy was 50 days (range, 19–150 days). Treatment variables, in addition to certain patient and tumor characteristics, were analyzed in terms of locoregional control and survival.

SETTING

Major referral tertiary center in central Israel.

RESULTS

Locoregional control rates were 86% and 81% at 2 and 5 years, respectively, and corresponding survival rates were 82% for both. Only nodal involvement retained statistical significance for both locoregional control as well as survival on multivariate analysis (P= 0.0009 andP= 0.0004, respectively).

CONCLUSIONS

This is the first study showing that delay in postoperative radiotherapy in advanced laryngeal cancer is not a significant predictor of locoregional control or survival in advanced laryngeal cancer. Only lymphatic spread was found to have a significant influence on treatment outcome.
Laser Cryptolysis for the Treatment of Halitosis
Authors: Finkelstein Yehuda , Talmi Yoav P. , Ophir Dov , Berger Gilead
Published: October 2004

OBJECTIVE

To evaluate the tonsils as a source of halitosis and to assess the efficacy of laser CO2 cryptolysis for the treatment of oral bad breath caused by chronic fetid tonsillitis.

METHODS

Fifty‐three patients with halitosis originating from chronic fetid tonsillitis, who completed laser cryptolysis were enrolled in the study. The origin of halitosis was demonstrated by Finkelstein's tonsil smelling test, which included massaging the tonsils and smelling the squeezed discharge. All patients were treated by laser cryptolysis, an office procedure done under topical anesthesia. Subjective and objective postoperative assessment was based on self‐and‐family report and clinical assessment. Patients were reexamined 4 to 6 weeks post‐treatment, and when the need for further laser treatment was determined.

RESULTS

Complete elimination of halitosis required one session in 28 patients (52.8%), 2 sessions in 18 patients (34%), and 3 sessions in 5 patients (9.4%). Follow‐up period ranged from 3 to 36 months (mean, 20.8 ± 8.5 months). No adverse effects or complications were encountered.

CONCLUSIONS

After excluding dental or periodontal, sinonasal, oral, pulmonary, or gastroenterological diseases as the origin of halitosis, chronic fetid tonsillitis remains a common cause of halitosis. Patients suffering from halitosis should be treated relying on their examination including Finkelstein's tonsil smelling test. Laser CO2 cryptolysis is an effective, safe, and well‐tolerated procedure for the treatment of halitosis.
A New Assay to Screen for Head and Neck Squamous cell Carcinoma Using the Tumor Marker Metallopanstimulin
Authors: Lee Wha‐Joon , Keefer K. , Hollenbeak C. S. , Stack B. C.
Published: October 2004

OBJECTIVE

To date, no serologic marker has proven effective as a diagnostic test for head and neck squamous cell carcinoma (HNSCC). Levels of metallopanstimulin (MPS), as measured by a difficult to reproduce radioimmunoassay, are significantly elevated in untreated HNSCC patients. Our objective was to develop a simpler MPS assay.

METHODS

Serum was obtained from HNSCC patients through Institutional Review Board approved protocols at the Penn State University College of Medicine and healthy volunteers donating blood at the hospital blood bank from 2000 to present. Serum MPS was immunoprecipitated, slot blotted, and Western blotted. MPS levels were quantified by densitometry.

RESULTS

Forty‐eight blood donors and 45 known HNSCC patients were studied. The MPS level was 14 ng/mL ± 1 (SEM) for blood donors and 36 ng/mL ± 3 (SEM) for known HNSCC patients. The difference was statistically significant (P < 0.0001).

CONCLUSION

Slot blot analysis of MPS is a safe, effective, and reproducible assay that may be used to screen for HNSCC in high‐risk populations.
Quality of Life in Hearing‐Impaired Adults: The Role of Cochlear Implants and Hearing Aids
Authors: Cohen Seth M. , Labadie Robert F. , Dietrich Mary S. , Haynes David S.
Published: October 2004

OBJECTIVE

To compare the quality‐of‐life (QOL) benefit received from cochlear implants (CIs) and hearing aids (HAs) among hearing‐impaired adults.

STUDY DESIGN

Health‐related questionnaire.

METHODS

Twenty‐seven CI users compared to control group of 54 HA users, both older than 49. Questionnaires for the pre‐rehab state (without HA or CI use) and post‐rehab state (after HA or CI for 12 months) were mailed 2 weeks apart.

RESULTS

Twenty‐six (96.3%) CI and 30 (55.6%) HA users responded (P < 0.001, chi‐square). Compared to HA patients, CI users showed twice as much overall QOL improvement (P = 0.082, multiple linear regression) as HA users. Multivariate analysis of variance showed greater QOL benefit in CI than HA users across the physical, psychological, and social subdomains (P = 0.03).

CONCLUSION

Cochlear implants provide at least comparable benefit for those with profound hearing loss as hearing aids bring for those with less severe hearing loss.
Pediatric Temporal Bone Fractures in a Rural Population
Authors: Ort Stuart , Beus Kirt , Isaacson Jon
Published: October 2004

OBJECTIVE

To examine pediatric temporal bone fractures in a rural population.

STUDY DESIGN AND SETTING

A retrospective chart review of pediatric temporal bone fractures between January 1, 1996, and December 31, 2000, at a rural academic medical center.

RESULTS

A total of 108 patients were identified. Common etiologies include falls, bicycle‐related injuries, and motor vehicle accidents. Animal‐related injuries were identified primarily in patients under 5. Facial nerve injuries were noted in 7%, hearing loss in 16%, additional skull base fractures in 65%, and intracranial injuries in 75%.

CONCLUSIONS

Temporal bone fracture etiology in the rural pediatric population is associated with age. Young children may suffer fractures secondary to animal‐related accidents. Patterns of injury differ little between rural and urban settings.

SIGNIFICANCE

Animal‐related accidents may be a significant cause of temporal bone trauma in rural young children. Our data remain unique in that we report additional skull base fractures as well as intracranial injuries in this population.
The Importance of Etiology on the Clinical Course of Neck Abscesses
Authors: Biller Jason A. , Murr Andrew H.
Published: October 2004

OBJECTIVE

Formation of neck abscesses from injecting illicit drugs continues to be a common problem in the United States. We sought to determine whether neck abscesses resulting from direct inoculation differ in their clinical course and severity from those that arise from direct spread through inflamed tissue, as in pharyngitis or odontogenic infections.

STUDY DESIGN AND SETTING

Patients were separated based on the cause of their neck abscess into either an injection drug use group or a noninjection drug use group. We retrospectively compared both groups of patients by examining multiple clinical endpoints, including the number of operations, length of hospital stay, and requirement for emergent airway intervention.

RESULTS

Injection drug use was the most common cause of neck abscess. Only 1 of these patients needed more than 1 drainage procedure, and no patients required emergent airway intervention or an intensive care unit (ICU) stay. The majority of the patients in the noninjection drug group had a neck abscess as a result of unknown causes; nearly one half required an emergent operation for airway management and the mean ICU stay was 2.5 days.

CONCLUSION

Neck abscesses formed by direct inoculation have a relatively more benign clinical course than those resulting from spread through inflamed tissue. The latter require a longer hospital stay, more days in the ICU, and more emergent intervention.
The Effect of Maxillary Sinus Antrostomy Size on Xenon Ventilation in the Sheep Model
Authors: Brumund Kevin T. , Graham Scott M. , Beck Kenneth C. , Hoffman Eric A. , McLennan Geoffrey
Published: October 2004

OBJECTIVE

A major goal of maxillary antrostomy is to increase sinus ventilation. Limited data exist regarding the effect of maxillary antrostomy size on sinus ventilation. We sought to quantify the effect of uncinectomy, small antrostomy, and large antrostomy on maxillary sinus ventilation using xenon‐enhanced CT in the sheep model.

MATERIALS, STUDY DESIGN, AND METHODS

A xe‐non‐oxygen‐air mixture was delivered to 8 fresh cadaveric sheep heads while repeated CT scans were performed through the maxillary sinuses. Baseline and postoperative studies were performed after an endoscopic uncinectomy, small antrostomy, or large antrostomy was created. Images were analyzed to measure the density of the xenon gas in the maxillary sinus as a function of time, generating a time constant.

RESULTS

The time constants for both small antrostomy and large antrostomy were significantly different compared to baseline (P = 0.003 for both). The time constant comparison between small antrostomy and large antrostomy was not significant (P = 0.948).

CONCLUSIONS

A small antrostomy produces a statistically significant increase in maxillary sinus ventilation over baseline. No significant further ventilation increase is obtained by creating a large antrostomy in the sheep model. This lends credence to the use of small antrostomies to improve maxillary sinus ventilation in human sinus surgery.
Medicaid Outpatient Utilization for Waterborne Pathogenic Illness following Hurricane Floyd
Authors: Setzer Christian , Domino Marisa Elena
Published: October 2004

Objectives.

Flooding provides an opportunity for epidemics of waterborne viral, protozoan, or bacterial diseases to develop in affected areas. Epidemic levels of disease may translate into higher than average levels of health services use, depending in part on help-seeking behaviors. The authors investigated whether the flooding that occurred as a result of Hurricane Floyd in September 1999 was associated with an increase in outpatient visits for waterborne diseases among Medicaid enrollees in eastern North Carolina.

Methods.

Using a difference-in-differences estimation technique, the authors examined the change in outpatient visits by North Carolina Medicaid enrollees for selected waterborne diseases following the hurricane. The study focused on counties with high concentrations of hog farming that were mildly/moderately or severely affected by the hurricane, using unaffected counties and the year before the hurricane as controls.

Results.

Small increases in Medicaid-covered outpatient visits were found in severely affected counties for two of the six pathogens selected for analysis, relative to unaffected counties. Larger increases in visits were found for nonspecific intestinal infections in both severely and moderately affected counties following the hurricane, relative to unaffected counties.

Conclusions.

The large increase in visits for ill-defined intestinal infection is noteworthy. The relative lack of increase in visits with specific pathogenic diagnoses may be attributable, at least in part, to a number of factors, including incomplete diagnostic information provided by treating clinicians, low treatment-seeking behavior, and use of non-Medicaid-funded emergency services.
The Interface Between the Practice of Medical Genetics and Human Genetic Research: What Every Genetic Counselor Needs to Know
Authors: Markel Dorene S. , Yashar Beverly M.
Published: October 2004

Genetic counselors have historically used human genetic research as an advanced information resource for their patients. Most commonly, this has been via access to information provided by gene identification studies in advance of commercial testing. More recently genetic counselors have been participating in human genetic research studies as part of the investigative team. This review provides a framework to help genetic counselors in research and clinical practice understand the historical perspectives, ethical principles, and federal regulations that govern the current practice of human subject research. Special consideration is given to∼the IRB process and unique issues in human genetic research. This overview is intended to help improve the ability of genetic counselors to act as advocates for their patients.
Patients' Knowledge of Cystic Fibrosis: Genetic Determinism and Implications for Treatment
Authors: Chapman Elizabeth , Bilton Diana
Published: October 2004

This paper uses the self‐regulation model of illness perceptions (Leventhal et al., 1984) to consider the implications of different ways of thinking about the causes of illness. The relationship between anxiety/depression and knowledge or denial of illness is also considered. These issues are explored using adherence to treatment in cystic fibrosis (CF) as an example. Twenty‐six CF patients took part in semistructured interviews and completed a standardized anxiety and depression scale (HAD, Zigmond and Snaith, 1983). Interview data were analyzed using Interpretative Phenomenological Analysis (Chapman and Smith, 2002). HAD data were analyzed using SPSS. The respondents displayed widely differing levels of knowledge of their condition. Some deterministic comments were also reported. Findings are discussed in relation to the information that physicians might provide to patients and families in the light of increasing knowledge about genetics in society and the genotyping of individuals with genetic conditions specifically. Any important gaps in patient knowledge could usefully be discussed at transition from pediatric to adult care and issues relating to control and genetic determinism discussed with the patients individually.
Does Receiving Genetic Counseling Impact Genetic Counselor Practice?
Authors: Peters Elizabeth , Veach Patricia McCarthy , Ward Erin E. , LeRoy Bonnie S.
Published: October 2004

This study was an investigation of whether genetic counselors have received genetic counseling and if so, how they believe it affects their practice. One thousand genetic counselors were mailed surveys about the nature of genetic counseling services received, impact on their clincal practice, frequency and reasons for disclosing about their receipt of counseling to their clients, and demographics. Ninety‐three of the 510 respondents reported receiving genetic counseling. Of these, almost three‐fourths were practicing genetic counselors while receiving services. Reasons for services include prenatal concerns, family history of cancer, and history/risk of other genetic conditions. Frequently endorsed effects on practice include increased empathy and understanding of client decisions, feeling more connected with clients, greater emphasis on psychosocial support, and sympathy. Forty‐six respondents disclosed to clients about their receipt of genetic counseling. Prevalent reasons include client asked, help clients feel they are not alone, demonstrate counselor understanding, decrease client anxiety, build rapport, and normalize client feelings. Practice and research recommendations are given.
Analyzing the Process and Content of Genetic Counseling in Familial Breast Cancer Consultations
Authors: Butow Phyllis N. , Lobb Elizabeth A.
Published: October 2004

A detailed examination of the process of genetic counseling has been identified as a priority area for research by previous authors. This multicenter longitudinal study examined the process and content of genetic counseling in initial consultations with women from high‐risk breast cancer families. One hundred and fifty‐eight consultations with women unaffected and affected with breast cancer were audio taped and transcribed verbatim. A detailed coding system was developed. Clinical geneticists and genetic counselors demonstrated consistently good practice in giving detailed information on essential aspects related to familial breast cancer such as screening and management, genetic testing, breast cancer genetics, and prophylactic surgery. Eliciting emotional concerns and facilitating communication were found to be inconsistently present. As clinical practice guidelines and the general communication literature emphasize the importance of these factors, this is an area where training in or self‐monitoring of such behaviors may assist consultants to further develop these skills.
Frequency and initiation of debris flows in Grand Canyon, Arizona
Authors: Griffiths Peter G. , Webb Robert H. , Melis Theodore S.
Published: October 2004

Debris flows from 740 tributaries transport sediment into the Colorado River in Grand Canyon, Arizona, creating rapids that control its longitudinal profile. Debris flows mostly occur when runoff triggers failures in colluvium by a process termed “the fire hose effect.” Debris flows originate from a limited number of geologic strata, almost exclusively shales or other clay‐rich, fine‐grained formations. Observations from 1984 through 2003 provide a 20 year record of all debris flows that reached the Colorado River in Grand Canyon, and repeat photography provides a 100 year record of debris flows from 147 tributaries. Observed frequencies are 5.1 events/year from 1984 to 2003, and historic frequencies are 5.0 events/year from 1890 to 1983. Logistic regression is used to model historic frequencies based on drainage basin parameters observed to control debris flow initiation and transport. From 5 to 7 of the 16 parameters evaluated are statistically significant, including drainage area, basin relief, and the height of and gradient below debris flow source areas, variables which reflect transport distance and potential energy. The aspect of the river channel, which at least partially reflects storm movement within the canyon, is also significant. Model results are used to calculate the probability of debris flow occurrence at the river over a century for all 740 tributaries. Owing to the variability of underlying geomorphic controls, the distribution of this probability is not uniform among tributaries of the Colorado River in Grand Canyon.
Major Pleistocene stages in a carbon perspective: The South China Sea record and its global comparison
Authors: Wang Pinxian , Tian Jun , Cheng Xinrong , Liu Chuanlian , Xu Jian
Published: October 2004

Carbon isotope sequences at Ocean Drilling Program Site 1143, South China Sea, reveal a long‐term cyclicity of ∼500 kyr that is superimposed on the glacial cycles and is present in long δ13C sequences from all oceans. The Quaternary δ13C record is punctuated by four δ13C maximum events: δ13Cmax‐I, which began in marine isotope stage (MIS) 3 around 50–60 kyr ago, δ13Cmax‐II (MIS 13, 0.47–0.53 Ma), δ13Cmax‐III (MIS 27–29, 0.97–1.04 Ma) and δ13Cmax‐VI (MIS 53–57, 1.55–1.65 Ma). As the same cyclicity is also found in carbonate curves, the δ13Cmax events must denote major reorganization in the carbon reservoir of the global ocean. They also are associated with major changes in glacial cyclicity, such as the Mid‐Brunhes Event following δ13Cmax‐II and the Mid‐Pleistocene Revolution following δ13Cmax‐III, which in turn were associated with expansion of the ice sheets. From a carbon perspective, therefore, the Quaternary period has passed through three major stages, and each appears to represent a further step in ice cap development.
Tracing water masses with 129I in the western Nordic Seas in early spring 2002
Authors: Alfimov V. , Aldahan A. , Possnert G.
Published: October 2004

The distribution of 129I was utilized for labeling water masses in three sections of the western Nordic Seas. An increase of the tracer in Polar Waters of the East Greenland Current was observed between the Fram Strait and 72°N section and attributed to either unaccounted Polar Waters and/or recirculation of cold and fresh Atlantic Waters from the West Spitzbergen Current. Recent convection homogenized 129I in upper 1000 m of the Greenland Sea, and similar concentrations were observed in dense waters of the Denmark Strait. The densest outflow waters were not found in either the Greenland Sea or the East Greenland Current at 72°N.
Physical‐biological oceanographic coupling influencing phytoplankton and primary production in the South China Sea
Authors: Ning X. , Chai F. , Xue H. , Cai Y. , Liu C. , Shi J.
Published: October 2004

Two cruises were carried out in the summer and winter of 1998 to study coupled physical‐chemical‐biological processes in the South China Sea and their effects on phytoplankton stock and production. The results clearly show that the seasonal distributions of phytoplankton were closely related to the coupled processes driven by the East Asian Monsoon. Summer southwesterly monsoon induced upwelling along the China and Vietnam coasts. Several mesoscale cyclonic cold eddies and anticyclonic warm pools were identified in both seasons. In the summer, the upwelling and cold eddies, both associated with rich nutrients, low dissolved oxygen (DO), high chlorophyll a (Chl a) and primary production (PP), were found in the areas off the coast of central Vietnam, southeast of Hainan Island and north of the Sunda shelf, whereas in the winter they form a cold trough over the deep basin aligning from southwest to northeast. The warm pools with poor nutrients, high DO, low Chl a, and PP were found in the areas southeast of Vietnam, east of Hainan, and west of Luzon during the summer, and a northwestward warm jet from the Sulu Sea with properties similar to the warm pools was encountered during the winter. The phytoplankton stock and primary production were lower in summer due to nutrient depletion near the surface, particularly PO4. This phosphorus depletion resulted in phytoplankton species succession from diatoms to dinoflagellates and cyanophytes. A strong subsurface Chl a maximum, dominated by photosynthetic picoplankton, was found to contribute significantly to phytoplankton stocks and production.
The Viable Systems Model Applied to a Smart Network: The Case of the UK Electricity Market
Authors: Shaw Duncan R , Snowdon Bob , Holland Christopher P. , Kawalek Peter , Warboys Brian
Published: October 2004

We investigate the concept of Smart Business Networks by using Beer's Viable System Model (VSM) to analyse how such a network mitigates the affect of emergent, and therefore unforecastable, demands upon the networked businesses. We examine the requirements for network smartness, highlight some significant properties of one Smart Network and use our case analysis and concepts from systems theory to suggest some general properties such as natural stability and distributed capability. We have found that smartness is distributed and shared behavioural process standards can act to stabilise complex systems. This is important because it mitigates emergent behaviour within increasingly complex business networks. The contributions of our article apply both to academics and business practitioners and are in its illustration and investigation of one Smart Business Network including how the smart capability functions at a strategic, business process and technical level; and the use of Beer's VSM to analyse an electricity market.
Study of high Mach number laser driven blast waves
Authors: Edens A. D. , Ditmire T. , Hansen J. F. , Edwards M. J. , Adams R. G. , Rambo P. , Ruggles L. , Smith I. C. , Porter J. L.
Published: October 2004

The study of blast waves produced by intense lasers in gases is motivated by the desire to explore astrophysically relevant hydrodynamic phenomena in the laboratory. A systematic scan of laser produced blast waves was performed and the structure of blast waves was examined over a wide range of drive laser energy. Lasers with energies ranging from 10–1000 J illuminated a pin target in either xenon or nitrogen gas, creating a spherical blast wave. A strongly radiating blast wave in xenon gas is observed while blast waves in nitrogen more closely approximate a pure Taylor–Sedov wave. It is also found that at all laser energies, blast waves traveling through xenon gas had their hydrodynamic evolution significantly affected by the passage of illumination laser.
Measurement of impurity emission profiles in CHS Plasma using AXUV photodiode arrays and VUV bandpass filters
Authors: Suzuki C. , Peterson B. J. , Ida K.
Published: October 2004

We have designed a compact and low-cost diagnostic system for spatiotemporal distributions of specific vacuum ultraviolet (VUV) emission lines from impurities in Compact Helical System (CHS) plasmas. The system consists of 20 channel absolute extreme ultraviolet photodiode arrays combined with interchangeable thin foil filters which have passbands in the VUV region. A compact mounting module which contains all the components including an in-vacuum preamplifier for immediate current–voltage conversion has been designed and successfully fabricated. A preliminary measurement with a single module using an aluminum foil filter has been carried out for monitoring the behavior of oxygen impurity in CHS, and initial results have been obtained. Two identical modules equipped with Versa Module European bus-based analog-digital converters will be available for future tomographic measurements.
Plasma radiometry with 30 chord resolution for fast transients in the DIII-D tokamak
Authors: Gray D. S. , Hollmann E. M. , Luckhardt S. C. , Chalfant J. , Chousal L. , Hernandez R. , Jones E. , Kellman A. G.
Published: October 2004

A diagnostic capable of providing time resolved measurements of plasma radiated power during disruptions and other fast transients, e.g., edge localized modes has been employed in the DIII-D tokamak. The radiation is detected with absolute extreme ultraviolet (AXUV) photodiode arrays. Thirty chords from a single port provide measurements from a full slice of the plasma at one toroidal location. The analog bandwidth is up to 1 MHz for the brightest events, i.e., disruptions. Active cooling of the diode arrays prevents damage during high temperature vessel baking. Effective responsivity values of 0.12–0.18 A/W are taken from previous work on the application of AXUV diodes in DIII-D. The total radiated energy in disruptions typically agrees with bolometer measurements within about 12%.
Measuring one-dimensional and two-dimensional impurity density profiles on TEXTOR using combined charge exchange-beam emission spectroscopy and ultrasoft x-ray tomography
Authors: De Bock M. , Jakubowska K. , Hellermann M. von , Jaspers R. , Donné A. J. H. , Shmaenok L.
Published: October 2004

Two techniques are presented that allow us to measure impurity density profiles in the TEXTOR tokamak plasma. The one-dimensional profiles are gathered by charge exchange recombination spectroscopy (CXRS) in combination with beam emission spectroscopy (BES). Combining CXRS and BES eliminate the need for absolute calibration. For two-dimensional profiles an ultrasoft x-ray tomography system has been developed. The system is spectrally resolved and produces local emissivity profiles of several ionization stages of impurities. Both systems are presently being commissioned. They are complementary and give an insight into the impurity distribution and transport in plasmas.
Optical and electrical diagnostics for the investigation of edge turbulence in fusion plasmas
Authors: Cavazzana R. , Scarin P. , Serianni G. , Agostini M. , Degli Agostini F. , Cervaro V. , Lotto L. , Yagi Y. , Sakakita H. , Koguchi H. , Hirano Y.
Published: October 2004

A new, two dimensional and fast diagnostic system has been developed for studying the dynamic structure of plasma turbulence; it will be used in the edge of the reversed-field pinch devices TPE-RX and RFX. The system consists of a gas-puffing nozzle, 32 optical channels measuring Hα emitted from the puffed gas (to study the optical emissivity of turbulent patterns and to analyze structures in two dimensions), and an array of Langmuir probes (to compare the turbulent pattern with the optical method and to measure the local plasma parameters). The signals can be acquired at 10 Msamples/s with 2 MHz band width. The design of the system, calibrations, and tests of the electronic circuitry and the optical sensors are presented.
Calibration of initial measurements from the full aperture backscatter system on the National Ignition Facility
Authors: Kirkwood R. K. , Mccarville T. , Froula D. H. , Young B. , Bower D. , Sewall N. , Niemann C. , Schneider M. , Moody J. , Gregori G. , Holdener F. , Chrisp M. , MacGowan B. J. , Glenzer S. H. , Montgomery D. S.
Published: October 2004

The full aperture backscatter system provides a measure of the spectral power, and integrated energy scattered by stimulated Brillouin (348–354 nm) and Raman (400–800 nm) scattering into the final focusing lens of the first four beams of the NIF laser. The system was designed to provide measurements at the highest expected fluences with: (1) spectral and temporal resolution, (2) beam aperture averaging, and (3) near-field imaging. This is accomplished with a strongly attenuating diffusive fiber coupler and streaked spectrometer and separate calibrated time integrated spectrometers, and imaging cameras. A new technique determines the wavelength dependent sensitivity of the complete system with a calibrated Xe lamp. Data from the calibration system are combined with scattering data from targets to produce the calibrated power and energy measurements that show significant corrections due to the broad band calibrations.
High speed movies of turbulence in Alcator C-Mod
Authors: Terry J. L. , Zweben S. J. , Bose B. , Grulke O. , Marmar E. S. , Lowrance J. , Mastrocola V. , Renda G.
Published: October 2004

A high speed (250 kHz), 300 frame charge coupled device camera has been used to image turbulence in the Alcator C-Mod Tokamak. The camera system is described and some of its important characteristics are measured, including time response and uniformity over the field-of-view. The diagnostic has been used in two applications. One uses gas-puff imaging to illuminate the turbulence in the edge/scrape-off-layer region, where D2 gas puffs localize the emission in a plane perpendicular to the magnetic field when viewed by the camera system. The dynamics of the underlying turbulence around and outside the separatrix are detected in this manner. In a second diagnostic application, the light from an injected, ablating, high speed Li pellet is observed radially from the outer midplane, and fast poloidal motion of toroidal striations are seen in the Li+ light well inside the separatrix.
One-, two-, and three-photon absorption induced fluorescence of a novel chromophore in chloroform solution
Authors: Wang Yuxiao , Tai Oliver Y.-H. , Wang C. H. , Jen Alex K.-Y.
Published: October 2004

One-, two-, and three-photon absorption induced fluorescence intensities of a novel nonlinear optical chromophore have been measured by using a tunable femtosecond pulsed laser as the excitation. Four resonance peaks are observed as the excitation wavelength is tuned from 600 to 2000 nm. These peaks correspond to the one-, two- and three-photon fluorescence resonance. Except for intensity difference, the lifetime and the fluorescence spectrum are found to be the same for the one-, two-, or three-photon resonance, hence suggesting that the same excited energy level is involved in emitting the fluorescence intensity. A three-level model is developed to account for the incident excitation laser intensity dependence of the one-photon and multiphoton fluorescence intensity. The model allows the multiphoton absorption cross sections to be extracted; it can also account for the deviation observed in the linear, square, and cubic intensity dependence of the one-, two-, and three-photon fluorescence intensity, respectively. To determine the absorption cross sections, the present method does not require the fluorescence quantum efficiency data, needed in the low intensity technique.
Accuracy of gates in a quantum computer based on vibrational eigenstates
Authors: Babikov Dmitri
Published: October 2004

A model is developed to study the properties of a quantum computer that uses vibrational eigenstates of molecules to implement the quantum information bits and shaped laser pulses to apply the quantum logic gates. Particular emphasis of this study is on understanding how the different factors, such as properties of the molecule and of the pulse, can be used to affect the accuracy of quantum gates in such a system. Optimal control theory and numerical time-propagation of vibrational wave packets are employed to obtain the shaped pulses for the gates NOT and Hadamard transform. The effects of the anharmonicity parameter of the molecule, the target time of the pulse and of the penalty function are investigated. Influence of all these parameters on the accuracy of qubit transformations is observed and explained. It is shown that when all these parameters are carefully chosen the accuracy of quantum gates reaches 99.9%.
The behavior of density functionals with respect to basis set. I. The correlation consistent basis sets
Authors: Wang Nick X. , Wilson Angela K.
Published: October 2004

The accuracy of density functional theory in the description of geometries and atomization energies has been assessed by comparison to experimental data for a series of first-row closed-shell molecules. Six commonly used functionals (B3LYP, B3PW91, B3P86, BLYP, BPW91, BP86) were investigated in combination with the correlation-consistent basis sets [cc-pVxZ and aug-cc-pVxZ where x=D(2), T(3), Q(4), 5]. The convergence of molecular properties with respect to increasing basis set size has been examined. A full statistical error analysis has been performed, assessing the success of each functional with respect to each basis set in terms of both accuracy and precision. Overall, there is smooth convergence towards the Kohn-Sham limit for the hybrid functionals B3LYP and B3PW91, whereas the nonlocal functionals are relatively insensitive to basis set choice.
Correlation energy of many-electron systems: A modified Colle–Salvetti approach
Authors: Ragot Sébastien , Cortona Pietro
Published: October 2004

The Colle and Salvetti approach [Theo. Chim. Acta 37, 329 (1975)] to the calculation of the correlation energy of a system is modified in order to explicitly include into the theory the kinetic contribution to the correlation energy. This is achieved by deducing from a many electrons wave function, including the correlation effects via a Jastrow factor, an approximate expression of the one-electron reduced density matrix. Applying the latter to the homogeneous electron gas, an analytic expression of the correlation kinetic energy is derived. The total correlation energy of such a system is then deduced from its kinetic contribution inverting a standard procedure. At variance of the original Colle–Salvetti theory, the parameters entering in both the kinetic correlation and the total correlation energies are determined analytically, leading to a satisfactory agreement with the results of Perdew and Wang [Phys. Rev. B 45, 13244 (1992)]. The resulting (parameter-free) expressions give rise to a modified-local-density approximation that can be used in self-consistent density-functional calculations. We have performed such calculations for a large set of atoms and ions and we have found results for the correlation energies and for the ionization potentials which improve those of the standard local-density approximation.