bluuebunny/crossref_metadata_2025 huggingface dataset:
Anomalous Origin of Right Coronary Artery from the Left Coronary Sinus: Incidence, Characteristics, and a Systematic Approach for Rapid Diagnosis
Authors: JIM MAN‐HONG , SIU CHUNG‐WAH , HO HEE‐HWA , MIU RAYMOND , LAM YUI‐MING , LAM LINDA , CHAN RAYMOND HON‐WAH , LEE STEPHEN WAI‐LUEN
Published: May 2005

Twenty‐three patients were found to have anomalous origin of right coronary artery from the left coronary sinus (LCS) from January 2000 to October 2003. The mean age was 58.6 ± 14.3 years with male predominance (56.5%). Cardiovascular risk factors were found in 18 (78.3%) patients while coronary artery disease was seen in 13 (56.5%) patients. Among the coronary artery disease patients, the left anterior descending artery was the most commonly involved, followed by the right coronary artery and the left circumflex artery. Right coronary artery dominance was seen in 19 (82.6%) patients. The anomalous right coronary artery originates within the left coronary sinus in 17 (73.9%) patients while from the left aortic wall above the sinus in 6 (26.1%) patients only. Congenital heart disease and acquired valvular heart disease were the most common associated conditions. The author will share his experience and suggest a four‐step approach of early recognition and selection of the anomalous right coronary artery ostium. Using the suggested strategy, most of the anomalous right coronary artery could be opacified with a left amplatz 1 catheter. Aortogram was needed only in 47.8% of cases.
Percutaneous Closure of Congenital and Acquired Ventricular Septal Defects—Considerations on Selection of the Occlusion Device
Authors: MICHEL‐BEHNKE INA , LE TRONG‐PHI , WALDECKER BERND , AKINTUERK HAKAN , VALESKE KLAUS , SCHRANZ DIETMAR
Published: May 2005

Nonsurgical closure of congenital and acquired ventricular septal defects (VSD) has become increasingly acceptable with the availability of various occlusion systems that allow percutaneous treatment of muscular and membranous defects. This study describes a series of 12 patients (0.2–74‐years‐old) who underwent defect closure with six different occlusion systems. Device selection according to anatomy and outcome is highlighted. Seven VSDs were located in the membranous part of the septum, five in the mid‐muscular septum. Complex heart lesions were present in five postmyocardial infarction VSD in one and residual postsurgical defects in three patients. The size of the VSD ranged from 2.6 to 10 mm. The applied devices were: Amplatzer muscular VSD occluder (n = 4), Amplatzer septal occluder (n = 2), Amplatzer duct occluder (n = 1), Amplatzer membranous VSD occluder (n = 2), Nit‐Occlud coil (n = 2), and Cook PDA coil (n = 1). The devices were implanted successfully in nine patients. There was complete VSD closure in eight patients within the first 24 hours. In one patient, a trivial residual shunt disappeared at 6 months follow‐up. Because of device instability, two occluders were removed during catheterization. In two other cases, tricuspid valve tissue was entrapped in the occluder and had to be removed surgically, one of them during the consecutive Rastelli operation. Neither significant arrhythmia, nor thromboembolism or hemolysis occurred in out patients during follow‐up. Transcatheter closure of VSD is an attractive alternative to surgery. In complex congenital heart disease, surgical‐interventional hybrid therapy may improve morbidity and total outcome. The recently developed Amplatzer VSD devices allow closure of muscular and membranous VSDs. Implantation and short‐term follow‐up are superior to the formerly used devices. Long‐term effects have to be evaluated in further studies.
Usefulness of Embolic Protection Devices During Saphenous Vein Graft Intervention in a Nonselected Population
Authors: WEBB LESLIE A. , DIXON SIMON R. , SAFIAN ROBERT D. , O'NEILL WILLIAM W.
Published: May 2005

Distal embolic protection devices have been shown to reduce the risk of peri‐procedural complications associated with saphenous vein graft intervention. However, there are several important anatomic limitations that may preclude routine device use. We analyzed the angiograms of 624 consecutive saphenous vein graft interventions to determine eligibility for use of a proximal or distal embolic protection system. Overall, 483 (77%) of cases had anatomic and lesion characteristics suitable for an embolic protection device, including 59% eligible for proximal protection and 57% for distal protection.
“Taking in the Waist”: Adjusting the Size of a Stented Fontan Fenestration
Authors: TORRES ALEJANDRO J. , HELLENBRAND WILLIAM E. , PASS ROBERT H.
Published: May 2005

Early spontaneous closure of a fenestration following Fontan palliation may complicate the postoperative management of such patients. The creation of a fenestration in the catheterization laboratory with an intravascular stent may improve these patients' hemodynamic status. The aim of this study is to present a new technique to reduce the diameter of stented Fontan fenestrations in those patients in whom the stent diameter is functionally made too large.
Comorbidity of physical and mental disorders and the effect on work‐loss days
Authors: Buist‐Bouwman M. A. , de Graaf R. , Vollebergh W. A. M. , Ormel J.
Published: May 2005

Objective:  To examine the association between physical and mental disorders and the separate and joint effect of physical and mental disorders on work‐loss.

Method:  Data was derived from the Netherlands Mental Health Survey and Incidence Study. This was a general population study in which 7076 adults, aged between 18 and 64 years, were assessed using the Composite International Diagnostic Interview. Medically treated physical disorders and work‐loss were assessed using self‐reports.

Results:  All physical disorders, except injury caused by accident, were significantly related to anxiety and mood disorders, but only weakly related to substance use disorders. Both physical and mental disorders were significantly related to work‐loss; mental disorders more so than physical disorders. Physical–mental (PM) comorbidity leads to a mainly additive increase in work‐loss.

Conclusion:  PM comorbidity is very common in the general population and leads to a greater absenteeism from work than pure disorders that also cause personal and social problems.
A review of studies describing the use of acetyl cholinesterase inhibitors in Parkinson's disease dementia
Authors: Maidment I. D. , Fox C. , Boustani M.
Published: May 2005

Objective:  To review the literature relating to the use of acetyl cholinesterase inhibitors in Parkinson's disease dementia (PDD).

Method:  MEDLINE (1966 – December 2004), PsychINFO (1972 – December 2004), EMBASE (1980 – December 2004), CINHAL (1982 – December 2004), and the Cochrane Collaboration were searched in December 2004.

Results:  Three controlled trials and seven open studies were identified. Efficacy was assessed in three key domains: cognitive, neuropsychiatric and parkinsonian symptoms.

Conclusion:  Cholinesterase inhibitors have a moderate effect against cognitive symptoms. There is no clear evidence of a noticeable clinical effect against neuropsychiatric symptoms. Tolerability including exacerbation of motor symptoms – in particular tremor – may limit the utility of cholinesterase inhibitors.
Does it make sense to do repeated surveys? – the Lundby Study, 1947–1997
Authors: Nettelbladt P. , Bogren M. , Mattisson C. , Öjesjö L. , Hagnell O. , Hofvendahl E. , Toråker P. , Bhugra D.
Published: May 2005

Objective:  To describe the Lundby Study and the difficulties in doing repeated surveys.

Method:  Best‐estimate consensus diagnoses have been used since 1957 together with DSM‐IV and ICD‐10 in 1997.

Results:  The Lundby population consisting of 3563 probands was investigated in 1947, 1957 and 1972. Sufficient information was available for 98–99%. In 1997–2000 a fourth field investigation was carried out. Attrition rate for the interviews was 13% (238/1797). About 36% (1030/2827) had died between 1972 and 1997, but data from registers, case notes and key‐informants for the period 1972 and 1997 completed the information for 94% (2659/2827). The population has followed the same pattern of development as many rural populations in Sweden since the 1940s. Multiple sources of information are preferable in longitudinal studies in order to tackle the problem of changing diagnostic systems.

Conclusion:  Low attrition rates over 50 years and reasonable diagnostic uniformity make comparisons over time justifiable.
Handedness in schizophrenia: a quantitative review of evidence
Authors: Dragovic M. , Hammond G.
Published: May 2005

Objective:  The prevalence of various anomalous handedness subtypes in schizophrenia patients remains ambiguous. Although current literature favours the notion that the shift in lateral preferences seen is because of an increase of mixed‐handedness, several studies suggest that exclusive left handedness is more prevalent than in the general population.

Method:  Over 40 studies with reported prevalence data on various handedness subtypes in a schizophrenia population were evaluated by meta‐analysis. Combined odds ratios for the three common handedness subtypes (left, mixed, and right) were separately calculated.

Results:  Each of the three atypical hand dominance patterns were significantly greater in schizophrenia patients than in control subjects, showing that the leftward shift in handedness distribution is not entirely because of an increase in mixed‐handedness alone.

Conclusion:  An increase of exclusive left‐handedness is at variance with the prevailing assertion that the handedness shift in schizophrenia patients is because of a diffuse and bilateral hemispheric insult.
Survival and bioenergetic responses of juvenile Atlantic salmon along a perturbation gradient in a natural stream
Authors: Coghlan S. M. , Ringler N. H.
Published: May 2005

Abstract – We tested the effects of a pollution gradient on the survival and energetic responses of Atlantic salmon fry stocked in Onondaga Creek, a historic but highly polluted nursery stream. A relatively unperturbed reference stream provided similar physical and thermal gradients that co‐varied longitudinally with the pollution gradient in Onondaga Creek, and macroinvertebrate communities provided indices of water quality degradation. Survival, cohort biomass, instantaneous growth rate and growth index of Atlantic salmon were inverse functions of water quality in the perturbed stream. Generally, survival and energetic parameters of Atlantic salmon responded differently to longitudinal gradients in the two streams, indicating that water quality, rather than habitat variation, exerted the strongest control over salmon. Effects were more pronounced during the early summer, possibly because tolerance to such perturbations increases with age or body size. Energetics‐related parameters were more sensitive to water quality than were survival‐related parameters, indicating that sub‐lethal effects of pollution may be detected and quantified by examining energy balances of individuals.
Population viability and perturbation analyses in remnant populations of the Andean catfish Astroblepus ubidiai
Authors: Vélez‐Espino L. A.
Published: May 2005

Abstract – Astroblepus ubidiai (Actinopterygii; Siluriformes), which is the only native fish of the highlands of the Province of Imbabura, Ecuador, was abundant in the past in the Imbakucha watershed and adjacent drainages but currently it is restricted to a few isolated refuges. Population viability analysis (PVA) was used to detect critical aspects in the ecology and conservation biology of this unique fish. The annual population growth rate (λ) was estimated for six remnant populations of this Andean catfish using a deterministic matrix population model. Sensitivity and elasticity analyses complemented the PVA by providing constructive insights into vital rates affecting projections and extinction probabilities. Positive population growth rates were found in all the study populations. The high contributions of juvenile survival to the variance of λ and its high elasticity indicated that A. ubidiai population dynamics are highly sensitive to the transition values of this vital rate, which can promptly respond to management or antagonistic perturbations. Allowing fish to survive until the age of first reproduction and permitting the successful reproduction of these individuals will facilitate positive population growth rates, however the very small areas of occupancy, small extent of occurrence and severe fragmentation may still contribute to the extinction risk.
Distribution and feeding of juvenile fish on invertebrates in littoral reed (Phragmites) stands
Authors: Okun N. , Mehner T.
Published: May 2005

Abstract – Complex interactions between fish predators and their prey have been found in structurally complex habitats built by submerged macrophytes. In contrast, the role of comparably structured littoral reed stands in shaping biotic interactions has not been investigated. We hypothesised that reed stands may be a valuable feeding habitat for juvenile fish, and that perch and roach may segregate along the spatial and dietary niche dimensions between reed and open water habitats. In contrast, the protection effect of reed against predators was assumed to be rather low because of the lower plant volume infested in reed when compared with submerged macrophytes. We analysed biomass and growth of juvenile (age 0 and age 1) perch and roach in littoral reed habitats and in open water habitats in front of the reed in the shallow Lake Müggelsee over 4 months in 2000. Sampling was conducted by point‐abundance electrofishing over the full diel cycle (day, dusk, night, dawn). Zooplankton and benthos biomasses were determined in both habitats as well, and habitat‐specific diet of fish was assessed during day and night. Roach were more frequent than perch in both habitats. Food of roach included a higher proportion of zooplankton, whereas perch fed more on macroinvertebrates. Overall, diet overlap between the fish groups was high. Diel distribution of fish did not follow the expectations of habitat segregation between perch and roach. Instead, the function of reed as refuge habitat against littoral piscivores (mainly birds) may have caused the strong daytime preference for reed in almost all fish groups, which was partly upset by roach at night. The higher behavioural plasticity of roach may explain their good performance even under the conditions of high structural complexity.
Discrimination of the natal origin of young‐of‐the‐year Allis shad (Alosa alosa) in the Garonne–Dordogne basin (south‐west France) using otolith chemistry
Authors: Tomás J. , Augagneur S. , Rochard E.
Published: May 2005

Abstract –  The otolith composition of age 0+ Allis shad (Alosa alosa) captured in two rivers in the Gironde system in south‐west France, the Dordogne and the Garonne, was analysed to establish the natal origin of the fish. Inductively coupled plasma mass spectrometry analyses were used to take measurements of 15 isotopes, among which Co, Fe, Sr and Rb were the most important elements in the discrimination process. It was possible to reclassify each sampled fish into its natal river basin (Garonne or Dordogne) with a high degree of accuracy. Linear discriminant analysis correctly reclassified 91.1% of the Garonne samples and 87.8% of the Dordogne samples (mean success in reclassification in 20 runs ± 1 SD: 89.21 ± 8.6%). Artificial neural networks correctly reclassified 90.1% of the Garonne samples and 81.2% of the Dordogne samples (mean success in reclassification after 1000 training cycles ±1 SD: 85.6 ± 9.1%). Using these tools the present results show that it is possible to assign a natal origin to juvenile shad that hatched in the Dordogne–Garonne basin based on the trace elements in the otolith.
The yellow European eel (Anguilla anguilla L.) may adopt a sedentary lifestyle in inland freshwaters
Authors: Laffaille P. , Acou A. , Guillouët J.
Published: May 2005

Abstract – We analysed the movements of the growing yellow phase using a long‐term mark–recapture programme on European eels in a small catchment (the Frémur, France). The results showed that of the yellow eels (>200 mm) recaptured, more than 90% were recaptured at the original marking site over a long period before the silvering metamorphosis and downstream migration. We conclude that yellow European eels >200 mm may adopt a sedentary lifestyle in freshwater area, especially in small catchment.
Homing behaviour of juvenile coho salmon (Oncorhynchus kisutch) within an off‐channel habitat
Authors: Minakawa N. , Kraft G. F.
Published: May 2005

Abstract – Although homing behaviour has been observed in juvenile Atlantic salmon, brown trout and resident cutthroat trout, this behaviour has not been well studied in juvenile Pacific salmon. We examined the site fidelity and homing behaviour of juvenile coho salmon (Oncorhynchus kisutch) by marking and relocating them within an off‐channel habitat. Over 80% of displaced fish returned to the area from which they were originally collected. The proportion of fish that returned to the original location did not vary significantly among three sampling dates. However, we found that this proportion decreased over time in a brackish lagoon when we statistically analysed the data reported by Day (1966). Our results suggest that juvenile coho salmon exhibit strong site fidelity and are able to return to their home ranges after displacement. These behaviours are likely to be important for the winter survival of juvenile coho salmon.
A Novel Hook‐Related Protein Family and the Characterization of Hook‐Related Protein 1
Authors: Simpson Fiona , Martin Sally , Evans Timothy M. , Kerr Markus , James David E. , Parton Robert G. , Teasdale Rohan D. , Wicking Carol
Published: May 2005

The spatial organization of organelles within a cell is dependent on microtubules. Recently, members of the Hook family of proteins have been proposed to function in linking organelles to microtubules. We report the identification of a completely novel protein family, the Hook‐related protein (HkRP) family, from which the Hook proteins have diverged. Bioinformatic analysis of the HkRP family revealed several conserved domains, including a unique C‐terminal HkRP domain. The central region of each protein is comprised of an extensive coiled‐coil domain, and the N‐terminus contains a putative microtubule‐binding domain. This domain has been shown to bind microtubules in the Hook protein and show that the HkRP1 protein is microtubule‐associated. While endogenous HkRP1 has no distinct organelle association, expression of the C‐terminal membrane‐binding domain suggests a function of the HkRP1 in early endosome. Ultrastructural studies reveal that expression of the C‐terminal HkRP1 domain causes an accumulation of internal membranes with an electron‐dense coat. Co‐localization studies show a concomitant redistribution of the early endosome marker sorting‐nexin 1 but not the early endosome antigen‐1 (EEA1). The steady‐state distribution of the epidermal growth factor receptor is also specifically disrupted by expression of the C‐terminal domain. We propose that HkRP1 is involved in the process of tubulation of sorting nexin‐1 positive membranes from early endosome subdomains.
HIV‐1 Trafficking to the Dendritic Cell–T‐Cell Infectious Synapse Uses a Pathway of Tetraspanin Sorting to the Immunological Synapse
Authors: Garcia Eduardo , Pion Marjorie , Pelchen‐Matthews Annegret , Collinson Lucy , Arrighi Jean‐Francois , Blot Guillaume , Leuba Florence , Escola Jean‐Michel , Demaurex Nicolas , Marsh Mark , Piguet Vincent
Published: May 2005

Dendritic cells (DCs) are essential components of the early events of HIV infection. Here, we characterized the trafficking pathways that HIV‐1 follows during its capture by DCs and its subsequent presentation to CD4+ T cells via an infectious synapse. Immunofluorescence microscopy indicates that the virus‐containing compartment in mature DCs (mDCs) co‐labels for the tetraspanins CD81, CD82, and CD9 but contains little CD63 or LAMP‐1. Using ratio imaging of pH‐reporting fluorescent virions in live DCs, we show that HIV‐1 is internalized in an intracellular endocytic compartment with a pH of 6.2. Significantly, we demonstrate that the infectivity of cell‐free virus is more stable at mildly acidic pH than at neutral pH. Using electron microscopy, we confirm that HIV‐1 accumulates in intracellular vacuoles that contain CD81 positive internal membranes but overlaps only partially with CD63. When allowed to contact T cells, HIV‐1‐loaded DCs redistribute CD81, and CD9, as well as internalized HIV‐1, but not the immunological synapse markers MHC‐II and T‐cell receptor to the infectious synapse. Together, our results indicate that HIV‐1 is internalized into a non‐conventional, non‐lysosomal, endocytic compartment in mDCs and further suggest that HIV‐1 is able to selectively subvert components of the intracellular trafficking machinery required for formation of the DC–T‐cell immunological synapse to facilitate its own cell‐to‐cell transfer and propagation.
Oral care and stroke units
Authors: Talbot Ana , Brady Marian , Furlanetto Denise L.C. , Frenkel Heather , Williams Brian O.
Published: May 2005

Objective:  To investigate oral care provision reported by senior nurses in stroke care settings in Scotland.

Background:  Stroke can have adverse effects on oral care and health. Little is known about current oral care practices in stroke care settings.

Materials and methods:  We designed a postal survey to be completed by ward managers or senior nurses. After piloting, the survey was distributed to all 71 units in Scotland, identified as providing specialist care for patients in the acute or rehabilitation stages following stroke. Pre‐notification and reminder letters were circulated. Responses were anonymous.

Results:  All but one survey was completed and returned. Help from dental professionals was available to most units (64/70) mostly on request. Only a third of units received oral care training in the last year (23/70). The majority of this training was ward based (20/23). The use of oral care assessment tools and protocols was limited (16/70 and 15/70 units respectively). Not all units had access to toothbrushes, toothpaste or chlorhexidine. For patients unable to perform oral care independently, senior nurses expected the patients’ teeth or dentures to be cleaned at least twice a day in 59 of 70 and 49 of 70 units respectively.

Conclusion:  The response rate was excellent and has provided a national overview of oral care provision for patients in stroke care settings. Access to staff training, assessments, protocols and oral hygiene material varied considerably. This information provides a valuable baseline from which to develop and evaluate the effectiveness of ward‐based oral care interventions for stroke patients.
‘Fiber 7’ supplement as an alternative to laxatives in a nursing home
Authors: Khaja M. , Thakur C. S. , Bharathan T. , Baccash E. , Goldenberg G.
Published: May 2005

Background:  Chronic constipation is a common and bothersome problem in elderly nursing home patients. Although fibre has a known role in the treatment of constipation, laxatives are still widely used in nursing home patients.

Objective:  To determine whether the addition of a fibre supplement to oral diet can reduce the use of laxatives in a long‐term care facility.

Participants and methods:  Oral diet of 92 nursing home residents (all older than 65) on chronic laxatives (docusate, milk of magnesia with Cascara, psyllium) was supplemented with ‘Fiber 7’, a natural powder fibre (7 g per meal twice a day). During the next 2.5 years discontinuation of laxatives was attempted.

Results:  Laxatives were successfully discontinued in 63 of the 92 patients (68.5%, 95% confidence interval 59–78%). The fibre supplement was well tolerated. The cost of care was decreased by $3.5 per patient every month or by $220/month for the 63 patients.

Conclusions:  Use of ‘Fiber 7’ allowed discontinuation of laxatives in 63 of 92 nursing home residents. The fibre supplement was a safe and convenient alternative to laxatives and decreased the cost of medical care.
Development of an index to measure oral health care priority among nursing staff
Authors: Wårdh Inger , Sörensen Stefan
Published: May 2005

Objective:  To develop an index to measure oral health care priority among nursing staff.

Background:  Nursing staff, working on hospital wards, at nursing homes and at other facilities, have to deal with oral health care and there are many reports about the low priority that is given to oral health care by nursing staff. It is difficult to measure oral health care priority among nursing staff. A Dental Coping Beliefs Scale (DCBS) index was used in an intervention study and was found to be easy to handle but did not have the ability to reveal significant differences in small study samples. A development process consisting of added items and item numbering by chance was carried out. During this process, different nursing staff test groups were used.

The aim was to develop an oral health care priority index that can be used both on hospital wards and at special facilities to measure oral health care priority among nursing staff over time and between groups.

Material and methods:  Nursing staff at both special facilities and hospital wards and nursing students.

Results:  It was found that the index, the nursing DCBS, was more stable compared with the version that was used in the initial intervention study. It was also noted that its ability to discriminate between the items was improved.

Conclusion:  The nursing DCBS index is a suitable tool for use in further studies where the aim is to measure how different nursing staff groups give priority to and allocate responsibility for oral health care, even where study samples are small.
Approximate discharge for constant head test with recharging boundary
Authors: Renard Philippe
Published: May 2005

The calculation of the discharge to a constant drawdown well or tunnel in the presence of an infinite linear constant head boundary in an ideal confined aquifer usually relies on the numerical inversion of a Laplace transform solution. Such a solution is used to interpret constant head tests in wells or to roughly estimate ground water inflow into tunnels. In this paper, a simple approximate solution is proposed. Its maximum relative error is on the order of 2% as compared to the exact analytical solution. The approximation is a weighted mean between the early‐time and late‐time asymptotes.
Influence of ancient thrust faults on the hydrogeology of the blue ridge province
Authors: Seaton William J. , Burbey Thomas J.
Published: May 2005

The Blue Ridge Province contains ubiquitous northeast‐southwest–trending thrust faults or smaller thrust “slivers” that greatly impact the nature and character of ground water flow in this region. Detailed investigations at a field site in Floyd County, Virginia, indicate that high‐permeability zones occur in the brittle crystalline rocks above these thrust faults. Surface and borehole geophysics, aquifer tests, and chlorofluorocarbon and geochemical data reveal that the shallow saprolite aquifer is separated from the deeper fault‐zone aquifer by a low–fracture permeability bedrock confining unit, the hydraulic conductivity of which has been estimated to be six orders of magnitude less than the conductivity of the fault zones at the test site. Within the Blue Ridge Province, these fault zones can occur at depths of 300 m or more, can contain a significant amount of storage, and yield significant quantities of water to wells. Furthermore, it is expected that these faults may compartmentalize the deep aquifer system. Recharge to and discharge from the deep aquifer occurs by slow leakage through the confining unit or through localized breach zones that occur where quartz accumulated in high concentrations during metamorphism and later became extensively fractured during episodes of deformation. The results of this investigation stress the importance of thrust faults in this region and suggest that hydrogeologic models for the Blue Ridge Province include these ancient structural features. Faults in crystalline‐rock environments may not only influence the hydrology, they may dominate the flow characteristics of a region.
Evaluation of time‐space distributions of submarine ground water discharge
Authors: Taniguchi Makoto , Ishitobi Tomotoshi , Saeki Ken‐ichi
Published: May 2005

Submarine ground water discharge (SGD) rates were measured continuously by automated seepage meters to evaluate the process of ground water discharge to the ocean in the coastal zone of Suruga Bay, Japan. The ratio of terrestrial fresh SGD to total SGD was estimated to be at most 9% by continuous measurements of electrical conductivity of SGD. Semidiurnal changes of SGD due to tidal effects and an inverse relation between SGD and barometric pressure were observed. Power spectrum density analyses of SGD, sea level, and ground water level show that SGD near shore correlated to ground water level changes and SGD offshore correlated to sea level changes. SGD rates near the mouth of the Abe River are smaller than those elsewhere, possibly showing the effect of the river on SGD. The ratio of terrestrial ground water discharge to the total discharge to the ocean was estimated to be 14.7% using a water balance method.
3H/3He age data in assessing the susceptibility of wells to contamination
Authors: Manning Andrew H. , Kip Solomon D. , Thiros Susan A.
Published: May 2005

Regulatory agencies are becoming increasingly interested in using young–ground water dating techniques, such as the 3H/3He method, in assessing the susceptibility of public supply wells (PSWs) to contamination. However, recent studies emphasize that ground water samples of mixed age may be the norm, particularly from long‐screened PSWs, and tracer‐based “apparent” ages can differ substantially from actual mean ages for mixed‐age samples. We present age and contaminant data from PSWs in Salt Lake Valley, Utah, that demonstrate the utility of 3H and 3He measurements in evaluating well susceptibility, despite potential age mixing. Initial 3H concentrations (measured 3H + measured tritiogenic 3He) are compared to those expected based on the apparent 3H/3He age and the local precipitation 3H record. This comparison is used to determine the amount of modern water (recharged after ∼1950) vs. prebomb water (recharged before ∼1950) samples might contain. Concentrations of common contaminants were also measured using detection limits generally lower than those used for regulatory purposes. A clear correlation exists between the potential magnitude of the modern water fraction and both the occurrence and concentration of contaminants. For samples containing dominantly modern water based on their initial 3H concentrations, potential discrepancies between apparent 3H/3He ages and mean ages are explored using synthetic samples that are random mixtures of different modern waters. Apparent ages can exceed mean ages by up to 13 years for these samples, with an exponential age distribution resulting in the greatest discrepancies.
Identifying connections in a fractured rock aquifer using ADFTs
Authors: Halihan Todd , Love Andrew , Sharp John M.
Published: May 2005

Fractured rock aquifers are difficult to characterize because of their extremely heterogeneous nature. Developing an understanding of fracture network hydraulic properties in these aquifers is difficult and time consuming, and field testing techniques for determining the location and connectivity of fractures in these aquifers are limited. In the Clare Valley, South Australia, well interference is an important issue for a major viticultural area that uses a fractured aquifer. Five fracture sets exist in the aquifer, all dipping >25°. In this setting, we evaluate the ability of steady‐state asymmetric dipole‐flow tests (ADFTs) to determine the connections between a test well and a set of piezometers. The procedure involves dividing a test well into two chambers using a single packer and pumping fluid from the upper chamber to the lower chamber. By conducting a series of tests at different packer elevations, an “input” signal is generated in fracture zones connected to the test well. By monitoring the “output” response of the hydraulic dipole field at piezometers, the connectivity of the fractures between the test well and piezometers can be determined. Results indicate the test well used in this study is connected in a complex three‐dimensional geometry, with drawdown occurring above and below areas of potentiometric buildup. The ADFT method demonstrates that the aquifer evaluated in this study cannot be modeled effectively on the well scale using continuum flow models.
Comparison of velocity‐log data collected using impeller and electromagnetic flowmeters
Authors: Newhouse M.W. , Izbicki J.A. , Smith G.A.
Published: May 2005

Previous studies have used flowmeters in environments that are within the expectations of their published ranges. Electromagnetic flowmeters have a published range from 0.1 to 79.0 m/min, and impeller flowmeters have a published range from 1.2 to 61.0 m/min. Velocity‐log data collected in five long‐screened production wells in the Pleasant Valley area of southern California showed that (1) electromagnetic flowmeter results were comparable within ±2% to results obtained using an impeller flowmeter for comparable depths; (2) the measured velocities from the electromagnetic flowmeter were up to 36% greater than the published maximum range; and (3) both data sets, collected without the use of centralizers or flow diverters, produced comparable and interpretable results. Although either method is acceptable for measuring wellbore velocities and the distribution of flow, the electromagnetic flowmeter enables collection of data over a now greater range of flows. In addition, changes in fluid temperature and fluid resistivity, collected as part of the electromagnetic flowmeter log, are useful in the identification of flow and hydrogeologic interpretation.
Predicting ground water nitrate concentration from land use
Authors: Gardner Kristin K. , Vogel Richard M.
Published: May 2005

Ground water nitrate concentrations on Nantucket Island, Massachusetts, were analyzed to assess the effects of land use on ground water quality. Exploratory data analysis was applied to historic ground water nitrate concentrations to determine spatial and temporal trends. Maximum likelihood Tobit and logistic regression analyses of explanatory variables that characterize land use within a 1000‐foot radius of each well were used to develop predictive equations for nitrate concentration at 69 wells. The results demonstrate that historic nitrate concentrations downgradient from agricultural land are significantly higher than nitrate concentrations elsewhere. Tobit regression results demonstrate that the number of septic tanks and the percentages of forest, undeveloped, and high‐density residential land within a 1000‐foot radius of a well are reliable predictors of nitrate concentration in ground water. Similarly, logistic regression revealed that the percentages of forest, undeveloped, and low‐density residential land are good indicators of ground water nitrate concentration >2 mg/L. The methodology and results outlined here provide a useful tool for land managers in communities with shallow water tables overlain with highly permeable materials to evaluate potential effects of development on ground water quality.
Process‐based interpretation of tracer tests in carbonate aquifers
Authors: Birk Steffen , Geyer Tobias , Liedl Rudolf , Sauter Martin
Published: May 2005

A tracer test in a carbonate aquifer is analyzed using the method of moments and two analytical advection‐dispersion models (ADMs) as well as a numerical model. The numerical model is a coupled continuum‐pipe flow and transport model that accounts for two different flow components in karstified carbonate aquifers, i.e., rapid and often turbulent conduit flow and Darcian flow in the fissured porous rock. All techniques employed provide reasonable fits to the tracer breakthrough curve (TBC) measured at a spring. The resulting parameter estimates are compared to investigate how each conceptual model of flow and transport processes that forms the basis of the analyses affects the interpretation of the tracer test. Numerical modeling results suggest that the method of moments and the analytical ADMs tend to overestimate the conduit volume because part of the water discharged at the spring is wrongly attributed to the conduit system if flow in the fissured porous rock is ignored. In addition, numerical modeling suggests that mixing of the two flow components accounts for part of the dispersion apparent in the measured TBC, while the remaining part can be attributed to Taylor dispersion. These processes, however, cannot reasonably explain the tail of the TBC. Instead, retention in immobile‐fluid regions as included in a nonequilibrium ADM provides a possible explanation.
Contaminant transport models under random sources
Authors: Patrick Wang P. , Zheng Chunmiao
Published: May 2005

While the discussion of model uncertainty has centered on spatial heterogeneity, it is possible that ground water models have not enjoyed much success as predictive tools often because the sources that were eventually imposed in the field differed from those represented in the simulations. This is because deterministic prediction of future conditions is often inaccurate due to the random nature of contaminant sources, in terms of their timing, location, and magnitude. This paper presents a stochastic framework for accommodating random contaminant sources in conventional, deterministic advection‐dispersion transport models. The contaminant sources are first classified into two types: those occurring continuously with a deterministic component and random variations and those occurring randomly at instantaneous discrete‐time intervals. For the first type, the governing partial differential equation (PDE) is replaced by a stochastic PDE. The random variations are modeled by Gaussian noise or Brownian motion, and the solution is obtained by using Ito's integration technique. For the second type, Markovian analysis is used for discrete‐time contamination events. Both approaches use a deterministic transport model to generate response functions at any observation location and time. The response functions are then integrated to yield probabilistic description of contaminant transport, from which key statistical properties such as mean, standard deviation, and confidence interval can be drawn.
On using simple time‐of‐travel capture zone delineation methods
Authors: Ceric Admir , Haitjema Henk
Published: May 2005

As part of its Wellhead Protection Program, the U.S. EPA mandates the delineation of “time‐of‐travel capture zones” as the basis for the definition of wellhead protection zones surrounding drinking water production wells. Depending on circumstances the capture zones may be determined using methods that range from simply drawing a circle around the well to sophisticated ground water flow and transport modeling. The simpler methods are attractive when faced with the delineation of hundreds or thousands of capture zones for small public drinking water supply wells. On the other hand, a circular capture zone may not be adequate in the presence of an ambient ground water flow regime. A dimensionless time‐of‐travel parameter T˜ is used to determine when calculated fixed‐radius capture zones can be used for drinking water production wells. The parameter incorporates aquifer properties, the magnitude of the ambient ground water flow field, and the travel time criterion for the time‐of‐travel capture zone. In the absence of interfering flow features, three different simple capture zones can be used depending on the value of T˜. A modified calculated fixed‐radius capture zone proves protective when T˜ < 0.1, while a more elongated capture zone must be used when T˜ >1. For values of T˜ between 0.1 and 1, a circular capture zone can be used that is eccentric with respect to the well. Finally, calculating T˜ allows for a quick assessment of the validity of circular capture zones without redoing the delineation with a computer model.
Modeling fracture porosity development using simple growth laws
Authors: Bloomfield John P. , Barker John A. , Robinson Nicola
Published: May 2005

A model of porosity development has been developed to investigate general relationships between simple fracture aperture growth laws and fracture porosity in evolved fracture arrays in aquifers. The growth of fracture apertures in two‐dimensional orthogonal arrays with initially spatially uncorrelated lognormal aperture distributions has been studied, where aperture growth rate is proportional to an exponent of the flow rate through each fracture. The evolved arrays show geometrical phase changes as a function of the aperture growth rate exponent,e, and the standard deviation of the initial aperture distribution,σz. Low values ofeandσzlead to bimodal aperture distributions, where apertures parallel to flow are preferentially enlarged. At moderate values ofeandσz, there is a transition to a regime of more complex geometries consisting of networks of channel‐like structures of preferentially enlarged apertures. At larger values ofe, array‐spanning channel‐like paths of preferentially enlarged apertures develop, where the tortuosity of the channel‐like paths is a linear function ofσz. Following an initial growth phase, during which dynamically stable aperture configurations develop, arrays undergo simple amplification. The geometry of the evolved aperture fields is diverse and they can be highly complex; consequently, parameterization and prediction of their evolution in terms of the initial aperture distributions and growth rate laws is not trivial.
Influence of injection conditions on field tracer experiments
Authors: Brouyère Serge , Carabin Guy , Dassargues Alain
Published: May 2005

Calibration of ground water transport models is often performed using results of field tracer experiments. However, little attention is usually paid to the influence, on resulting breakthrough curves, of injection conditions and well‐aquifer interactions, more particularly of the influence of the possible trapping of the tracer in the injection wellbore. Recently, a new mathematical and numerical approach has been developed to model injection conditions and well‐aquifer interactions in a very accurate way. Using an analytical solution derived from this model, a detailed analysis is made of the evolution of the tracer input function in the aquifer. By varying injection conditions from one simulation to another, synthetic breakthrough curves are generated with the SUFT3D ground water flow and transport finite‐element simulator. These tests show clearly that the shape of the breakthrough curves can be dramatically affected by injection conditions. Using generated breakthrough curves as “actual” field results, a calibration of hydrodispersive parameters is performed, neglecting the influence of injection conditions. This shows that neglecting the influence of actual injection conditions can lead to (1) errors on fitted parameters and (2) misleading identification of the active transport processes. Conclusions and guidelines are drawn in terms of proposed methodologies for better controlling the tracer injection in the field, in order to minimize risk of misinterpretation of results.
Calculation of ground water ages—A comparative analysis
Authors: Castro Maria Clara , Goblet Patrick
Published: May 2005

Ground water age is a fundamental, yet complex, concept in ground water hydrology. Discrepancies between results obtained through different modeling approaches for ground water age calculation have been reported, in particular, between ground water ages modeled by advection and direct simulation of ground water ages (e.g., age‐mass approach), which includes effects of advection and dispersion. Here, through a series of two‐dimensional (2D) simulations, the impact of water mixing through advection and dispersion on modeled 14C and directly simulated ground water ages is assessed. Impact of dispersion on modeled ages is systematically stronger in areas where water velocities are smaller and far more pronounced on 14C ages. This effect is also observed in one‐dimensional models. 2D simulations show that longitudinal dispersion generally acts as a “source” of 14C, while vertical dispersion acts as a “sink,” leading to apparent younger or older modeled 14C ages as compared to advective and directly simulated ground water ages. The presence of permeable and impermeable faults provides an equally important source for discrepancies, leading to major differences in modeled ages among the three methods considered. Overall, our results show that a 14C modeling approach using a solute transport model for calculating ground water age appears to be more reliable in ground water systems without faults and where water velocities are relatively high than in systems that are relatively more heterogeneous and those where faults are present. Among the three modeling approaches considered here, direct simulation of ground water age seems to yield the most consistent results in complex, heterogeneous ground water flow systems, giving a vertical age structure consistent with ages expected from consideration of the flow system.
Longitudinal dispersivity data and implications for scaling behavior
Authors: Schulze‐Makuch Dirk
Published: May 2005

Longitudinal dispersivity (α) data were compiled from 109 different authors for different types of geological media. The data were subdivided into different subsets. Dispersivity values for consolidated media were subdivided as basalts, granites, sandstones, and carbonate rocks, while unconsolidated sediments were subdivided into three reliability classes. The data sets provided here may provide ground water practitioners a preliminary guide to estimate dispersivity values at various scales and to guide and verify theories on scaling behavior. Based on the data set presented here, the relationship that empirically best described the dispersivity data in regard to scale of measurement was in the form of a power law. The scaling exponent for consolidated and unconsolidated geological media varied between 0.40 and 0.92, and 0.44 and 0.94, respectively. Higher reliability subsets of data for the unconsolidated sediments and more frequently tested rock formations indicate that the scaling exponent is at the lower end of the observed range, close to 0.5. No significant difference in scaling exponent was found among different media, and no clear evidence exists for the presence of an upper bound or asymptotic behavior on the relationship for any of the analyzed media.
Interaction of tSNARE Syntaxin 18 with the Papillomavirus Minor Capsid Protein Mediates Infection
Authors: Bossis Ioannis , Roden Richard B. S. , Gambhira Ratish , Yang Rongcun , Tagaya Mitsuo , Howley Peter M. , Meneses Patricio I.
Published: May 2005

The papillomavirus capsid mediates binding to the cell surface and passage of the virion to the perinuclear region during infection. To better understand how the virus traffics across the cell, we sought to identify cellular proteins that bind to the minor capsid protein L2. We have identified syntaxin 18 as a protein that interacts with bovine papillomavirus type 1 (BPV1) L2. Syntaxin 18 is a target membrane-associated soluble
N
-ethylmaleimide-sensitive factor-attachment protein receptor (tSNARE) that resides in the endoplasmic reticulum (ER). The ectopic expression of FLAG-tagged syntaxin 18, which disrupts ER trafficking, blocked BPV1 pseudovirion infection. Furthermore, the expression of FLAG-syntaxin 18 prevented the passage of BPV1 pseudovirions to the perinuclear region that is consistent with the ER. Genetic studies identified a highly conserved L2 domain, DKILK, comprising residues 40 to 44 that mediated BPV1 trafficking through the ER during infection via an interaction with the tSNARE syntaxin 18. Mutations within the DKILK motif of L2 that did not significantly impact virion morphogenesis or binding at the cell surface prevented the L2 interaction with syntaxin 18 and disrupted BPV1 infection.