bluuebunny/crossref_metadata_2025 huggingface dataset:
Lig‐8, a Highly Bioactive Lignophenol Derivative from Bamboo Lignin, Exhibits Multifaceted Neuroprotective Activity
Authors: Ito Yasushi , Akao Yukihiro , Shimazawa Masamitsu , Seki Norio , Nozawa Yoshinori , Hara Hideaki
Published: August 2007

Lignin is a durable aromatic network polymer that is second only to cellulose in natural abundance. Lig‐8, a lignophenol derivative from bamboo lignin, is a highly potent neuroprotectant. It protects human neuroblastoma cells (SH‐SY5Y) from hydrogen peroxide (H2O2)–induced apoptosis by preventing caspase‐3 activation via either caspase‐8 or caspase‐9. It exerts this antiapoptotic effect by protecting mitochondrial membrane permeability from damage by H2O2 or the peripheral benzodiazepine receptor ligand PK11195. Lig‐8 has been also shown to scavenge the reactive oxygen or nitrogen species in vitro. Furthermore, lig‐8 suppresses apoptosis induced by oxygen‐glucose deprivation, tunicamycin (endoplasmic reticulum [ER]–stress inducer), or proteasome inhibitor in pheochromocytoma cells. In addition, in vivo, lig‐8 reduced intravitreal N‐methyl‐d‐aspartate–induced retinal damage (decreases in retinal ganglion cells and inner plexiform layer thickness) in mice. Lig‐8 prevents neuronal damage partly by inhibiting excessive endoplasmic reticulum stress. In this article, we review the protective effects of lig‐8 against apoptosis induced by various stimuli. Apoptosis is an active, energy‐dependent process through which living cells initiate their own death. It can be induced by a variety of physiological and pharmacological stimuli. Apoptotic cell death is associated with neurodegenerative disorders such as Alzheimer, Parkinson, or Huntington disease as well as glaucoma. We believe that the elucidation of the mechanism of antiapoptotic action of lig‐8 may help in finding new approaches to the treatment of neurodegenerative disorders.
Ethanol Consumption Modifies Dendritic Cell Antigen Presentation in Mice
Authors: Heinz Richard , Waltenbaugh Carl
Published: August 2007

Background:  Alcohol consumption impairs type 1 cell‐mediated adaptive immune responses both in vivo and in vitro. The present study investigated the effect of alcohol consumption on antigen‐presenting cell (APC) populations and cytokine production.

Methods:  BALB/c were fed ethanol‐containing, pair‐fed isocaloric liquid control, or solid diets for 11 days. Macrophage and dendritic cell (DC) populations were isolated by paramagenetic bead separation and used to present ovalbumin (OVA) to highly purified syngeneic CD4+ T cells derived from DO11.10 T cell receptor transgenic mice in coculture. DC isolated from diet‐fed mice were also used to present OVA to highly purified CD4+ T cells derived from antigen‐naïve DO11.10Rag2−/− mice that are devoid of memory T cells. In vitro cytokine responses, interleukin (IL) ‐2, IL‐6, IL‐12, IL‐13, IL‐17A, and interferon‐γ (IFN‐γ) were measured by enzyme‐linked immunosorbent assay. Flow cytometry measured cell surface molecule expression.

Results:  Alcohol consumption impairs delayed hypersensitivity responses (type 1) and enhances serum IgE levels (type 2). CD11c+ DC, but not F4/80+ macrophages, support cytokine responses by purified CD4+ T cells. CD11c+ DC derived from ethanol consuming BALB/c mice show diminished ability to support IFN‐γ responses by purified CD4+ T cells derived from DO11.10 or DO11.10Rag2−/− mice. Subset analysis indicates that of the 3 “conventional” DC subsets found in mouse spleens, CD11c+CD8+ DCs are both responsible for OVA presentation and susceptible to the effects of ethanol. Ethanol consumption does not overtly alter the percent of splenic DC, but does increase the surface density of CD11c on these cells. Data show that cocultures containing purified CD4+ T DO11.10 cells and APC derived from alcohol‐consuming mice show decreased IL‐6, IL‐12, IL‐17A, and IFN‐γ and increased IL‐13 cytokine production in response to OVA stimulation.

Conclusions:  Ethanol alters CD11c+CD8+ DC function, affecting cytokines responsible for adaptive immune responses. A unifying hypothesis for the underlying mechanism(s) of ethanol’s effect upon adaptive immune function is proposed.
Danger Zones: Risk Perceptions of Young Women From Families With Hereditary Breast and Ovarian Cancer
Authors: WERNER‐LIN ALLISON V.
Published: August 2007

Genetic testing for hereditary breast and ovarian cancer (HBOC) is predictive, not prophetic. Families frequently rely on multigenerational stories to make sense of the inherent ambiguity as they face medical decisions and navigate life's journeys. This study asks young women with elevated genetic risk how family histories with cancer and experiences with health professionals inform their beliefs about risk and susceptibility to HBOC. Twenty‐two women aged 22–36 who carry a BRCA mutation completed illness genograms and open‐ended interviews. Transcripts were analyzed using a narrative tool that emphasizes the use of voice to highlight key relationships and meaning structures. Findings reveal that beliefs about risk are more firmly grounded in family experiences with cancer than in biomedical research. Pervasive meanings included (1) the presence of “danger zones,” specific ages at which cancer risk was believed to increase dramatically, and (2) the experience of “the wait and the worry,” in which participants felt increased urgency to achieve family development goals (i.e., child bearing) and limited control over environmental factors influencing when these goals could be met (i.e., meeting a life partner). A clinical case example and research implications are discussed.
Ab Initio Calculation of Elastic Constants of Ceramic Crystals
Authors: Yao Hongzhi , Ouyang Lizhi , Ching Wai‐Yim
Published: August 2007

An effective computational scheme to calculate the complete set of independent elastic constants as well as other structural parameters including bulk modulus, shear modulus, Young's modulus, and Poisson's ratio for crystals is reported. The scheme is based on the stress–strain analysis approach with the appropriate selection of strain governed by symmetry consideration. The first principles Vienna ab initio simulation package (VASP) is used in stress calculations. Comprehensive tests were performed for α‐SiO2 and spinel MgAl2O4 with different exchange‐correlation potentials, and different sets of computational parameters to investigate the relative accuracies of the calculations. A wide range of oxides, nitrides, and carbonate crystals with different crystal symmetries were chosen to test the scheme under both LDA and GGA approximations at zero temperature and pressure. Some of these calculations for large complex crystals are believed to be attempted for the first time. The calculated elastic constants show quite good agreement with the existing experimental data for almost all the examined systems with the exception of the relatively soft material such as α‐SiO2 and the C14 parameter of some trigonal crystals expressed in the hexagonal form such as in α‐Al2O3. Other structural properties derived from the elastic constants also show good agreements with the measured values.
New Family of Dielectric Materials in Ca–Y–Ti–Nb–O System Having Pyrochlore Type Structure
Authors: Nair K. Ravindran , Rao P. Prabhakar , Raj Anupama V. , Joseph Smila K. , Chandran Marottikunnathu Raman , Koshy Peter
Published: August 2007

A new family of pyrochlore‐type oxides in the Ca–Y–Ti–Nb–O system has been prepared by the conventional solid‐state route. These compounds have a dielectric constant (K) in the range 27–92 and, further, the dielectric properties are found to be independent of frequency in the 100 Hz to 1 MHz range for all the compositions in the temperature range 30°–100°C. Their temperature coefficient of the dielectric constant is negative and in the range −80 to −612 ppm/°C. Rietveld analysis of the X‐ray diffraction data establishes a cubic pyrochlore‐type phase in the space group Fd3m (no. 227). A variation in the stoichiometry of the cations in the system does not change the pyrochlore‐type structure.
Formation of High‐Quality, Epitaxial La2Zr2O7 Layers on Biaxially Textured Substrates by Slot‐Die Coating of Chemical Solution Precursors
Authors: Wee Sung‐Hun , Goyal Amit , Hsu Huey , Li Jing , Heatherly Lee , Kim Kyunghoon , Aytug Tolga , Sathyamurthy Srivatsan , Parans Paranthaman Mariappan
Published: August 2007

Crystallization studies were performed of epitaxial La2Zr2O7 (LZO) films on biaxially textured Ni–3at.%W substrates having thin Y2O3 (10 nm) seed layers. LZO films were deposited under controlled humid atmosphere using reel‐to‐reel slot‐die coating of chemical solution precursors. Controlled crystallization under various processing conditions has revealed a broad phase space for obtaining high‐quality, epitaxial LZO films without microcracks, with no degradation of crystallographic texture and with high surface crystallinity. Crack‐free and strong c‐axis aligned LZO films with no random orientation were obtained even at relatively low annealing temperatures of 850°–950°C in flowing one atmosphere gas mixtures of Ar–4% H2 with an effective oxygen partial pressure of P(O2)∼10−22 atm. Texture and reflection high‐energy electron diffraction analyses reveal that low‐temperature‐annealed samples have strong cube‐on‐cube epitaxy and high surface crystallinity, comparable to those of LZO film annealed at high temperature of 1100°C. In addition, these samples have a smoother surface morphology than films annealed at higher temperatures. Ni diffusion rate into the LZO buffer film is also expected to be significantly reduced at the lower annealing temperatures.
Optical Spectra of Copper‐Doped Zn‐Phosphate Glasses
Authors: Goldstein Adrian , Vulfson Marina , Sirota Marina
Published: August 2007

Copper‐containing, binary, Zn‐phosphate glasses were melted under reductive conditions. The profile of their optical spectra and their color change drastically when the ZnO content of the host is modified. An increase in the host's ZnO concentration tilts the copper oxidation state's equilibria toward the reduced species Cu+ and Cu0. In hosts containing more than 52 mol% ZnO, the Cu0 aggregates precipitate upon melt cooling to form ruby glasses. The ruby color also appears in glasses including 50 mol% ZnO, after thermal treatments. The effect of ZnO increase, in the composition of binary Zn‐phosphate glasses, on the redox equilibria of a copper dopant, is inverse to that caused by increase of Na2O content in the case of Na‐phosphate hosts.
Search for evidence of recurring or persistent viruses in Crohn's disease
Authors: VAN KRUININGEN HERBERT J. , POULIN MICHELLE , GARMENDIA ANTONIO E. , DESREUMAUX PIERRE , COLOMBEL JEAN‐FRÉDÉRIC , DE HERTOGH GERT , GEBOES KAREL , VERMEIRE SEVERINE , TSONGALIS GREGORY J.
Published: August 2007

New‐onset Crohn's disease and acute flares are often associated with viral infections. The aim of this study was to search for evidence of persistent or recurrent viruses in patients. Tissue blocks were obtained from surgical specimens from patients and a control population. 111 samples were tested by PCR or RT‐PCR, for EBV, CMV, HSV 1, HSV 2, HHV 8, pestiviruses, and enteroviruses. Additionally, seven sets of serum samples, including pre‐operative and post‐operative samples, from CD patients were analyzed serologically for antibodies to EBV. The tests revealed evidence of EBV nucleic acid in tissues of 11 patients from a total of 70 tested (15.7%) and in tissues of 3 of 41 control subjects (7.3%). Evidence of pestivirus was found in one CD patient, while one patient and one control were positive for CMV. No HSV 1 or 2, HHV 8 or enteroviruses were found. The serologic tests revealed that five of seven CD patients had antibodies against the early protein, the capsid protein and the EBV nuclear antigen (EBNA). The titers were not significantly altered post‐surgically. None of the patients had antibodies of the IgM isotype. Our findings vary from those of Ruther et al. who demonstrated evidence of EBV in tissues from 7 of 11 (64%) German CD patients. Antibodies to early EBV viral antigen and to nuclear antigen in five of seven Belgian patients suggest persistent active viral infection.
CD40/CD40L expression in leukocytes from chronic granulomatous disease patients
Authors: SALMEN SIHAM , CORTE DANIELA , GONCALVES LOREDANA , BARBOZA LUISA , MONTES HENRY , CALDERÓN ALí , BERRUETA LISBETH
Published: August 2007

Chronic granulomatous disease (CGD) is an inherited disorder caused by defects in the NADPH oxidase complex, which generates superoxide, the precursor of hydrogen peroxide (H2O2) and other reactive oxygen derivatives with microbicidal activity. Because CGD patients are at risk of chronic inflammatory manifestations, including inflammatory bowel disease and autoimmune diseases, and it is not clear whether these pathologies are exclusively secondary to altered superoxide production, or whether distinct immunologic defects are involved, we explored cell proliferation, lymphocyte cell counts, immunoglobulin levels, presence of autoimmune antibodies and expression of costimulatory molecules in leukocytes from CGD patients. We found that CGD patients have a diminished phytohemagglutinin‐induced proliferation of blood mononuclear cells. Following stimulation with PMA plus ionomycin, a reduced percentage of CD40L expression in T lymphocytes and a diminished expression of CD40 molecules in neutrophils were observed on leukocytes from these patients. Our results suggest an altered interplay between elements of innate and adaptive immunity in CGD patients, which may be reflected in an increased susceptibility to opportunistic infections.
Elevated matrilysin levels in bronchoalveolar lavage fluid do not distinguish idiopathic pulmonary fibrosis from other interstitial lung diseases
Authors: VUORINEN KIRSI , MYLLÄRNIEMI MARJUKKA , LAMMI LAURI , PIIRILÄ PÄIVI , RYTILÄ PAULA , SALMENKIVI KAISA , KINNULA VUOKKO L.
Published: August 2007

Microarray studies have shown that matrilysin or matrix metalloproteinase (MMP)‐7 is highly upregulated in the lungs of patients with idiopathic pulmonary fibrosis (IPF), but MMP‐7 protein expression has not been systematically compared between IPF and other interstitial lung diseases. MMP‐7 levels in bronchoalveolar lavage fluid (BALF) were compared to corresponding samples from nonspecific interstitial pneumonia (NSIP), sarcoidosis, and healthy controls. MMP‐7 levels in the BALF were determined by ELISA and localization of MMP‐7 in the lung tissue by immunohistochemistry. MMP‐7 was similarly elevated in the BALF of all these disorders compared to healthy controls (p=0.007). Even control subjects with prolonged cough displayed a tendency towards elevated MMP‐7 expression. There was a negative correlation between BALF MMP‐7 levels and forced expiratory vital capacity (r=−0.348, p=0.02, n=42). In IPF lung, MMP‐7 immunoreactivity appeared predominantly in the fibrotic parenchyma and arterial wall. In sarcoidosis and NSIP, prominent MMP‐7 immunoreactivity was found in areas of inflammation. These results demonstrate that elevated BALF MMP‐7 is not restricted to IPF alone but is also observed in other interstitial lung diseases and cannot be used as a differential diagnostic marker for IPF.
EMMPRIN and fascin overexpression associated with clinicopathologic parameters of pancreatobiliary adenocarcinoma in Chinese people
Authors: TSAI WEN‐CHIUAN , CHAO YOU‐CHEN , SHEU LAI‐FA , LIN YEH‐FENG , NIEH SHIN , CHEN ANN , YU CHENG‐PIN , JIN JONG‐SHIAW
Published: August 2007

The aim of this study was to test whether expression of EMMPRIN and fascin correlates with clinicopathologic parameters of pancreatobiliary adenocarcinoma. Immunohistochemical analysis of EMMPRIN and fascin was performed in 100 surgical specimens obtained from Chinese patients, including 18 well‐differentiated, 62 moderately differentiated, and 20 poorly differentiated pancreatic and biliary adenocarcinomas. Neither EMMPRIN nor fascin was detectable in normal pancreatic and biliary glandular epithelia. However, EMMPRIN and fascin immunoreactivity was observed on the cell membrane and within the cytoplasm in pancreatobiliary adenocarcinomas. Higher immunostaining scores of EMMPRIN and fascin were strongly associated with advanced grades of pancreatobiliary adenocarcinomas (36.1 and 51.3 for grade I, 95.5 and 110.1 for grade II, and 133.7 and 165.8 for grade III). In addition, higher immunostaining scores of EMMPRIN and fascin were associated with advanced T stages (29.8 and 43.6 for T1, 86.3 and 93.2 for T2, 107.6 and 117.6 for T3, and 129.5 and 156.5 for T4). Higher EMMPRIN and fascin scores were associated with shorter survival times and more advanced M and N stages of pancreatiobiliary adenocarcinomas. A higher expression of EMMPRIN and fascin was found to correlate well with histologic grades and clinical stages of pancreatobiliary adenocarcinomas.
The differential expression of proteins in the cortical cells of wool and hair fibres
Authors: Plowman Jeffrey E. , Paton Louise N. , Bryson Warren G.
Published: August 2007

Abstract:  Three different cell types have been identified in the cortex of wool: orthocortex, mesocortex and paracortex. Fine wool fibres, particularly Merino sheep, are noted for their bilateral distribution of orthocortical and paracortical cells, with the latter following the concave side of the crimp wave. Furthermore, studies have indicated that the paracortex has a higher concentration of cysteine than the orthocortex. This has been supported by in situ hybridization studies in the follicle that have shown that sulphur‐rich proteins are initially expressed on the paracortical side of the fibre, with some becoming more uniformly spread, laterally, over the entire fibre as the keratinization process progresses. In contrast, proteins high in glycine and tyrosine tend to be expressed initially on the orthocortical side of the follicle. While these in vitro studies have pointed to where specific proteins are located in the follicle, elucidating the situation for the mature fibre has been less easy. A range of approaches have been used to separate orthocortical and paracortical cells and these have only been able to provide evidence for a higher level of cysteine in the latter. Electrophoretic studies have found a number of differences in protein expression between the two sides but have not specifically identified which proteins. Thus, there appears to be good evidence for the paracortex containing a higher proportion of proteins in the ultra‐high sulphur class but there is some uncertainty regarding the exact distribution of proteins high in glycine and tyrosine.
Expression of the human Cathepsin L inhibitor hurpin in mice: skin alterations and increased carcinogenesis
Authors: Walz Markus , Kellermann Sabine , Bylaite Matilda , Andrée Birgit , Rüther Ulrich , Paus Ralf , Kloepper Jennifer E. , Reifenberger Julia , Ruzicka Thomas
Published: August 2007

Abstract:  The serine protease inhibitor (serpin) hurpin (serpin B13) is a cross class‐specific inhibitor of the cysteine protease Cathepsin (Cat) L. Cat L is involved in lysosomal protein degradation, hair follicle morphogenesis, epidermal differentiation and epitope generation of antigens. Hurpin is a 44 kDa protein which is expressed predominantly in epidermal cells. In psoriatic skin samples, hurpin was strongly overexpressed when compared with normal skin. Keratinocytes overexpressing hurpin showed increased resistance towards UVB‐induced apoptosis. To further analyse the functional importance of this inhibitor, we have generated transgenic mice with deregulated Cat L activity by expressing human hurpin in addition to the endogenous mouse inhibitor. The three independent transgenic lines generated were characterized by identical effects excluding insertional phenotypes. Macroscopically, mice expressing human hurpin are characterized by abnormal abdominal fur. The number of apoptotic cells and caspase‐3 positive cells was reduced after UV‐irradiation in transgenic animals compared with wild‐type mice. Interestingly, after chemical carcinogenesis, transgenic mice showed an increased susceptibility to develop skin cancer. Array analysis of gene expression revealed distinct differences between wild‐type and hurpin‐transgenic mice. Among others, differentially expressed genes are related to antigen presentation and angiogenesis. These results suggest an important role of Cat L regulation by hurpin which might be of clinical relevance in human skin diseases.
Strong cellular and humoral immune responses induced by transcutaneous immunization with HBsAg DNA–cationic deformable liposome complex
Authors: Wang Jing , Hu Jin‐hong , Li Feng‐qian , Liu Guan‐zhong , Zhu Quan‐gang , Liu Ji‐yong , Ma Hong‐jun , Peng Cheng , Si Fu‐guo
Published: August 2007

Abstract:  Transcutaneous immunization presents a major challenge on account of poor permeability of antigens through the skin barrier. To overcome this limitation, the deformable liposome could be a better method for transcutaneous delivery of these antigens. In this study, hepatitis B surface antigen (HBsAg) plasmid DNA–cationic complex deformable liposome was utilized as a mode for enhanced immunity against the antigen. Deformable liposome was prepared by conventional rotary evaporation method and characterized for various parameters such as vesicles shape and surface morphology, size and size distribution, entrapment efficiency, elasticity and stability. The immune stimulating activity was studied by measuring serum anti‐HBsAg titre and cytokines level (interleukin‐4 and interferon‐γ) following topical application of liposome in BALB/c mice and results were compared with deformable liposome encapsulated DNA applied topically as well as naked DNA and pure recombinant HBsAg, administered intramuscularly. It was observed that deformable liposome elicited a comparable serum antibody titre and endogenous cytokines levels compared to other vaccinations. The study signifies the potential of deformable liposome as DNA vaccine carriers for effective transcutaneous immunization.
Suppressive effect of orally administered copper(II)‐aspirinate (Cu2(asp)4) complex on the generation of reactive oxygen species in the skin of animals subjected to UVA exposure
Authors: Fujimori Takako , Yasui Hiroyuki , Hiromura Makoto , Sakurai Hiromu
Published: August 2007

Abstract:  As reactive oxygen species (ROS) are involved in the pathogenesis of various diseases, superoxide dismutase (SOD) and its mimetic complexes have been intensively studied. Recently, we found that Cu2(aspirinate)4 (Cu2(asp)4) has both in vitro and in vivo antioxidative activities. We investigated the suppressive effect of Cu2(asp)4 on ROS generation in the skin of hairless mice that were orally administered Cu2(asp)4 and followed by UVA exposure. The results were compared with those obtained from mice that were orally administered Cu(salicylate)2 (Cu(sal)2) or Cu(acetate)2, (Cu(ace)2) and followed by UVA exposure. After confirming that Cu2(asp)4 suppressed ROS generation in the skin, we measured both SOD activity and metallothionein (MT) and SOD protein levels in the whole proteins extracted from the skin of ICR mice that were orally administered Cu(II) compounds. The Cu2Zn2‐SOD activity was enhanced by the administration of Cu(II) compounds; however, no alterations in the protein levels of MT and SOD were observed. Metallokinetics of the paramagnetic Cu(II) species in the circulating blood of rats, as estimated by electron spin resonance (ESR), revealed that among the Cu(II) compounds, the residence time of the Cu(II) species from Cu2(asp)4 was the longest. On the basis of these results, we conclude that Cu2(asp)4 is an orally potent antioxidative compound that suppresses ROS generation in the skin. The residence time of Cu(II) in the blood and the enhanced SOD activity in the skin following the oral administration of Cu2(asp)4 support this conclusion. Here, we propose that Cu2(asp)4 may be used to protect the skin against ROS generation.
Chitosan adsorption to salivary pellicles
Authors: Van Der Mei Henny C. , Engels Eefje , De Vries Joop , Dijkstra Rene J. B. , Busscher Henk J.
Published: August 2007

The salivary pellicle is a negatively charged protein film, to which oral bacteria readily adhere. Chitosans are cationic biomolecules with known antimicrobial properties that can be modified in different ways to enhance its antimicrobial activity. Here, we determined the changes in surface chemical composition using X‐ray photoelectron spectroscopy (XPS), in hydrophobicity by analyzing water contact angles, in charge through measuring streaming potentials, and evaluated morphology using atomic force microscopy (AFM), of salivary pellicles upon adsorption of different chitosans. The adsorption of chitosans to pellicles was chemically evident from altered carbon functionalities and the presence of an N1s peak at 401.1 eV as a result of protonated amines in XPS. Chitosan adsorption made the pellicle (zeta potential of untreated pellicles 29 mV) positively charged and more hydrophobic. A chemically modified chitosan (CL) and an unmodified chitosan (UC) caused aggregation of adsorbed salivary proteins, and AFM revealed clumps of protein after treatment with these chitosans, yielding an increase in pellicle surface roughness from 5.1 nm to between 16.3 and 35.6 nm for CL and UC, respectively. In summary, chitosans have a clear tendency to adsorb to salivary pellicles with a profound effect on the surface properties of the pellicle. Therefore, chitosans may provide anchoring molecules to affix antimicrobials to pellicle surfaces.
Lactobacillus‐mediated interference of mutans streptococci in caries‐free vs. caries‐active subjects
Authors: Simark‐Mattsson Charlotte , Emilson Claes‐Göran , Håkansson Eva Grahn , Jacobsson Catharina , Roos Kristian , Holm Stig
Published: August 2007

In order to assess whether naturally occurring oral lactobacilli have probiotic properties, lactobacilli were isolated from saliva and plaque from children and adolescents, with or without caries lesions. The interference capacities of these lactobacilli were investigated against a panel of 13 clinical isolates and reference strains of Streptococcus mutans and Streptococcus sobrinus, as well as against the subject's autologous mutans streptococci, using the agar‐overlay technique. Lactobacillus‐mediated inhibition differed significantly between the three subject groups (no caries, arrested caries, or active caries), demonstrating increased inhibition in subjects without present or previous caries experience compared to subjects with arrested caries or subjects presenting with frank lesions. Lactobacilli from subjects lacking S. mutans inhibited the growth of the test panel of mutans streptococci significantly better than lactobacilli from subjects who were colonized. Furthermore, subjects without caries experience harbored lactobacilli that more effectively repressed the growth of their autologous mutans streptococci. Twenty‐three Lactobacillus spp. completely inhibited the growth of all mutans streptococci tested. Species with maximum interference capacity against mutans streptococci included Lactobacillus paracasei, Lactobacillus plantarum, and Lactobacillus rhamnosus. Naturally occurring oral lactobacilli significantly inhibited the growth of both test strains of mutans streptococci and the subject's autologous mutans streptococci in vitro, and this effect was more pronounced in caries‐free subjects.
The “People” Factor in Cooperatives: An Analysis of Members' Attitudes and Behavior
Authors: Bhuyan Sanjib
Published: August 2007

Members' attitudes and perceptions play a significant role in their behavior toward their organization and the performance of such organizations. This study examines the role of these “people” factors in a sample of fruit and vegetable growers' cooperatives in the Mid‐Atlantic United States. Although the Theory of Planned Behavior is used as the framework of analysis, the objective of this study was not to test the theory. Study findings provide additional insights into how cooperative members' beliefs and knowledge may shape their attitudes and the consequent behavior. Given the gradual decline of both cooperative memberships and the number of cooperatives in the United States and other countries, a good understanding of members' attitudes and behaviors is necessary because a cooperative's success may depend on it.

Les attitudes et les perceptions des membres d'une coopérative jouent un rôle important dans le comportement envers l'organisme et la performance de ce dernier. La présente étude a examiné le rôle de ces facteurs ≪humains≫ dans un échantillon de coopératives de producteurs de fruits et légumes dans les États du centre du littoral atlantique. Bien que la théorie du comportement axé sur un objectif ait été utilisée comme cadre d'analyse, l'objectif de l'étude ne consistait pas à tester la théorie. Les résultats de l'étude ont fourni des éclaircissements supplémentaires sur la façon dont les croyances et les connaissances des membres d'une coopérative peuvent façonner leurs attitudes et leur comportement subséquent. Compte tenu du déclin progressif du nombre de membres de coopérative et du nombre de coopératives aux États‐Unis et dans d'autres pays, il est important de bien comprendre les attitudes et les comportements des membres puisque le succès d'une coopérative peut en dépendre.
Quality Uncertainty and Challenges to Wheat Procurement
Authors: Wilson William W. , Dahl Bruce L. , Demcey Johnson D.
Published: August 2007

Issues related to quality uncertainty in wheat producing countries have escalated in importance in recent years. While Canada addresses these issues in part through variety regulations, firms in the United States resolve these through varying commercial strategies. Conventional alternatives for procurement range from spot purchases with specifications for easily measurable characteristics, to varying forms of strategies with precommitment. In grains, these are complicated by intrinsic uncertainty associated with functional qualities that are not easily measurable and that procurement costs vary spatially. Thus, shifting origins may involve higher cost due to having to bid grain away from its best market. We posed alternative procurement strategies and developed analytical models to evaluate the costs and risks of these in the case of hard red spring (HRS) wheat. Climatic conditions are a source of uncertainty in functional performance which reduces incentives for contracting and vertical integration, and poses a challenge to any form of integrated supply chain management.

Les problèmes liés à l'incertitude quant à la qualité des approvisionnements des pays producteurs de blé ont augmenté au cours des dernières années. Tandis que le Canada s'attaque à ces problèmes en imposant divers règlements, des entreprises états‐uniennes les résolvent en adoptant diverses stratégies commerciales. Les moyens d'approvisionnement traditionnels varient des achats au comptant assortis de critères pour les caractéristiques facilement mesurables, à diverses stratégies comprenant un pré‐engagement. Dans le secteur des céréales, la situation est compliquée par l'incertitude intrinsèque quant aux qualités fonctionnelles qui ne sont pas facilement mesurables et le fait que les coûts d'approvisionnements varient d'un endroit à l'autre. Par conséquent, s'approvisionner dans d'autres pays pourrait entraîner des coûts plus élevés en privant le secteur de son meilleur marché. Nous avons formulé d'autres stratégies d'approvisionnement et élaboré des modèles analytiques pour évaluer les coûts et les risques de ces stratégies dans le cas du blé de force roux de printemps. Les conditions climatiques sont une source d'incertitude de la qualité fonctionnelle qui diminue les incitatifs pour la conclusion de contrat et l'intégration verticale et qui pose un obstacle pour toute forme de gestion intégrée de la chaîne d'approvisionnement.
Ouverture des marchés et localisation des productions agricoles Market openness and location of agricultural activities
Authors: Daniel Karine
Published: August 2007

Nous analysons dans cet article l'impact de l'ouverture des marchés sur la localisation des activités agricoles et agro‐alimentaires entre deux régions représentant de manière stylisée l'Union européenne et le reste du monde. L'analyse repose sur un modèle d'économie géographique qui considère certaines caractéristiques de l'agriculture et des marchés de produits alimentaires. Dans un cadre de marché en concurrence monopolistique où les produits sont différenciés horizontalement et verticalement, il apparaît que l'ouverture du marché induit dans tous les cas une baisse de la production communautaire. Seule une forte différentiation des produits selon leur origine géographique permet de limiter cette baisse.

We analyze, in this article, the effect of a liberalization of the markets on the location of agricultural and agro‐food activities, between two stylized regions: the European Union and the rest of the world. We build an economic geography model. It considers the specificity of the agricultural activity and the food markets. In a monopolistic competition framework where the products are horizontally and vertically differentiated, we show that the openness of the market induces a decrease of the production in the European Union. Only a strong differentiation of the production according to its geographic origin can limit this effect.
Inverse Modeling of Coastal Aquifers Using Tidal Response and Hydraulic Tests
Authors: Alcolea Andrés , Castro Eduardo , Barbieri Manuela , Carrera Jesús , Bea Sergio
Published: August 2007

Remediation of contaminated aquifers demands a reliable characterization of hydraulic connectivity patterns. Hydraulic diffusivity is possibly the best indicator of connectivity. It can be derived using the tidal response method (TRM), which is based on fitting observations to a closed‐form solution. Unfortunately, the conventional TRM assumes homogeneity. The objective of this study was to overcome this limitation and use tidal response to identify preferential flowpaths. Additionally, the procedure requires joint inversion with hydraulic test data. These provide further information on connectivity and are needed to resolve diffusivity into transmissivity and storage coefficient. Spatial variability is characterized using the regularized pilot points method. Actual application may be complicated by the need to filter tidal effects from the response to pumping and by the need to deal with different types of data, which we have addressed using maximum likelihood methods. Application to a contaminated artificial coastal fill leads to flowpaths that are consistent with the materials used during construction and to solute transport predictions that compare well with observations. We conclude that tidal response can be used to identify connectivity patterns. As such, it should be useful when designing measures to control sea water intrusion.
Flow to a Well in a Five‐Layer System with Application to the Oxnard Basin
Authors: Li Yanhua , Neuman Shlomo P.
Published: August 2007

Nearly 40 years ago, Neuman (1968) developed an analytical solution for drawdown in a system of three aquifers separated by two aquitards when one of the aquifers is pumped at a constant rate. Whereas the simpler case of two aquifers separated by one aquitard has been presented by Neuman and Witherspoon (1969a), the full five‐layer solution has not been previously evaluated. We do so here using numerical inversion of its Laplace‐transformed version and present selected results graphically in dimensionless form. The solution demonstrates that the effect of pumping propagates across all five layers, adding emphasis to a question previously raised by Neuman and Witherspoon about the validity of leaky aquifer theories that disregard drawdowns in unpumped aquifers. A large‐scale, long‐term pumping test spanning three aquifers separated by two aquitards near Oxnard, California, has been conducted and analyzed by Neuman and Witherspoon (1972). They evaluated the vertical hydraulic diffusivities of the aquitards using the Neuman‐Witherspoon ratio method and their specific storage values on the basis of laboratory consolidation tests. We reinterpret the Oxnard pumping test by coupling the five‐layer analytical solution of Neuman (1968) with the parameter estimation code PEST (Doherty 2002) and validate our results against drawdowns from a subsequent pumping test at the site. Our parameter estimates compare favorably with those of Neuman and Witherspoon (1972).
Estimating Ground Water Recharge using Flow Models of Perched Karstic Aquifers
Authors: Weiss Menachem , Gvirtzman Haim
Published: August 2007

The fraction of rain that is annually recharged to ground water is a function of the transient quantities of precipitation (wet vs. dry years) as well as other meteorological and geologic factors, and thus it is very difficult to estimate. In this study, we have used long records (20 to 30 years) of precipitation and spring discharge to reconstruct the transient character of yearly recharge. These data sets were used to calibrate numerical ground water flow models on the less than 3 km2 scale for four separate perched karstic aquifers in the Judean and Samarian Mountains of Israel. The stratification and karstic character of the local carbonate rock aquifers cause ground water to flow through discrete dissolution channels and to discharge at isolated springs. An innovative, dual‐porosity approach was used where a finite‐difference solution simulates flow in the rock matrix, while the karstic channels are simulated using computationally simple drains. Perched conditions are also simulated innovatively using MODFLOW by treating the bottom unsaturated layer as if it is saturated, but by assuming zero pressure head throughout the “unsaturated” layer. Best fitting between measured and computed spring hydrograph data has allowed us to develop a set of empirical functions relating measured precipitation to recharge to the aquifer. The generic methodology presented gives insight into the suspected changes in aquifer recharge rates between particularly wet or dry years.
Energetic Compound False Positives in Ground Water Profile Samples
Authors: Clausen Jay , Wessling Elizabeth , Chirgwin Brad
Published: August 2007

The analytical procedure U.S. EPA SW‐846 method 8330 is the predominant technique used for analysis of energetic compounds in water and soil. The basis for compound identification is nonspecific and for some complex samples may yield false‐positive results for energetic compounds. Suspended particulates and drilling fluids are potential interferents introduced to ground water profile samples. Profile samples had a higher frequency of false positives relative to monitoring well samples. Additionally, the false‐positive frequency was lower in samples where no lubricants or greases were used during drilling and sampling. Protocol refinements, the inclusion of photodiode array (PDA) spectral analysis, visual inspection of chromatograms and PDA spectra, and careful manual data evaluation have reduced false‐positive detections. A project team investigating ground water with the potential for energetic compounds must have extensive experience with method 8330, knowledge of how to use PDA analysis, and experience in interpreting chromatograms and PDA spectra for the target compounds.
Ground Water Transfer Initiates Complete Reductive Dechlorination in a PCE‐Contaminated Aquifer
Authors: Lookman R. , Paulus D. , Marnette E. , Pijls C. , Ryngaert A. , Diels L. , Volkering F.
Published: August 2007

We conducted a field test to investigate whether ground water transfer from one site (showing complete natural reductive dechlorination of chlorinated ethenes to ethene) could induce full reductive dechlorination at another site polluted with tetrachloroethene and its partial dechlorination products trichloroethene and cis‐dichloroethene (cDCE). Addition of electron donor (lactate) at the test site established low redox conditions but did not stimulate further dechlorination past cDCE. After transferring 2 m3 of ground water from the first site to the test site, full dechlorination commenced and high levels of ethene were measured to distances up to 6 m downstream of the injection location within 7 months. Ground water samples from monitoring wells were analyzed before and after inoculation of the test site for the presence of Dehalococcoides species (16S ribosomal RNA) and vinyl chloride reductase (vCRA) genes using the polymerase chain reaction. These tests showed that Dehalococcoides species were present both before and after ground water transfer, while vCRA genes were detected at the test site only after ground water transfer. The vCRA genes were detected in ground water samples collected 6 m downstream of the injection locations 7 months after ground water transfer, suggesting that the microorganisms carrying the dehalogenase genes were effectively transported in the aquifer.
EVALUATING INTERDEPENDENT WATERSHED CONSERVATION AND GROUND WATER MANAGEMENT REFORMS1
Authors: Pitafi Basharat A. , Roumasset James A.
Published: August 2007

Abstract: Conserving the watershed can help to preserve ground water recharge. Preventing overuse of available water through pricing reforms can also substantially increase the value of an aquifer. Inasmuch as users are accustomed to low prices, efficiency pricing may be politically infeasible, and watershed conservation may be considered as an alternative. We estimate and compare welfare gains from pricing reform and watershed conservation for a water management district in Oahu that obtains its water supply from the Pearl Harbor aquifer. We find that pricing reform is welfare superior to watershed conservation unless the latter is able to prevent very large recharge losses. Watershed conservation that yields net gains in combination with pricing reform may cause net losses without the pricing reform. If adoption of watershed conservation delays the implementation of pricing reform, the benefits of the latter are significantly reduced.
REAL‐TIME SOIL WATER MONITORING FOR OPTIMUM WATER MANAGEMENT1
Authors: Fares Ali , Hamdhani H. , Polyakou Viktor , Dogan A. , Valenzuela Hector
Published: August 2007

Abstract: Efficient water resource management is one of the most important policy issues facing agriculture in Hawaii in the years ahead. Soil water sensors, multisensor capacitance probes (MCP), have been successfully used for different water management projects. These MCPs monitor water content at multiple depths and at various locations in real‐time. The objectives of this study were to determine the effect of water content on field soil bulk density of Wahiawa silty clay tropical soil; measure field saturated hydraulic conductivity of this tropical soil: calibrate MCP system for this soil: and monitor and evaluate real‐time soil water content variations under a tomato crop using the calibrated MCP system. Sensor calibration was conducted under laboratory conditions. Soil bulk density at different water contents and saturated hydraulic conductivity were measured on the field. Bulk density increased with increasing water content: there was a 30 percent bulk density increase as a result of 0.25 cm3 cm‐3 water content variation. Compared with the manufacturer's calibration, site specific laboratory calibration of MCP gave a more accurate determination of soil water. Field determined saturated hydraulic conductivity was higher than laboratory determined values reported in the literature for the same soil type. Real‐time soil water content monitoring within the root zone showed substantial variations due to water input (irrigation and rainfall) and water output (evapotranspiration and deep percolations). However, water content variations were much further reduced in the soil layer below the root zone.
MULTICOMPONENT GEOCHEMICAL TRANSPORT MODELING USING HYDRUS‐1D AND HP11
Authors: Š;imůnek Jirka , Jacques Diederik , Van Genuchten Martinus Th. , Mallants Dirk
Published: August 2007

Abstract: The transport of reactive contaminants in the subsurface is generally affected by a large number of nonlinear and often interactive physical, chemical, and biological processes. Simulating these processes requires a comprehensive reactive transport code that couples the physical processes of water flow and advective‐dispersive transport with a range of biogeochemical processes. Two recently developed coupled geochemical models that are both based on the HYDRUS‐1D software package for variably saturated flow and transport are summarized in this paper. One model resulted from coupling HYDRUS‐1D with the UNSATCHEM module. While restricted to major ion chemistry, this program enables quantitative predictions of such problems as analyzing the effects of salinity on plant growth and the amount of water and amendments required to reclaim salt‐affected soil profiles. The second model, HPI, resulted from coupling HYDRUS‐1D with the PHREEQC biogeochemical code. The latter program accounts for a wide range of instantaneous or kinetic chemical and biological reactions, including complexation, cation exchange, surface complexation, precipitation dissolution and/or redox reactions. The versatility of HP1 is illustrated in this paper by means of two examples: the leaching of toxic trace elements and the transport of the explosive TNT and its degradation products.
BIVARIATE FREQUENCY ANALYSIS OF FLOODS USING COPULAS1
Authors: Shiau Jenq‐Tzong , Wang Hsin‐Yi , Tsai Chang‐Tai
Published: August 2007

Abstract: Bivariate flood frequency analysis offers improved understanding of the complex flood process and useful information in preparing flood mitigation measures. However, difficulties arise from limited bivariate distribution functions available to jointly model the correlated flood peak and volume that have different univariate marginal distributions. Copulas are functions that link univariate distribution functions to form bivariate distribution functions, which can overcome such difficulties. The objective of this study was to analyze bivariate frequency of flood peak and volume using copulas. Separate univariate distributions of flood peak and volume are first fitted from observed data. Copulas are then employed to model the dependence between flood peak and volume and join the predetermined univariate marginal distributions to construct the bivariate distribution. The bivariate probabilities and associated return periods are calculated in terms of univariate marginal distributions and copulas. The advantage of using copulas is that they can separate the effect of dependence from the effects of the marginal distributions. In addition, explicit relationships between joint and univariate return periods are made possible when copulas are employed to construct bivariate distribution of floods. The annual floods of Tongtou flow gauge station in the Jhuoshuei River, Taiwan, are used to illustrate bivariate flood frequency analysis.
MULTIFRACTAL SCALING OF DAILY RUNOFF TIME SERIES IN AGRICULTURAL WATERSHEDS1
Authors: Zhou Xiaobo , Persaud Naraine , Wang Huaguo , Lin Hangsheng
Published: August 2007

Abstract:Multifractal scaling behavior of long‐term records of daily runoff time series in 32 subwatersheds covering a wide range of sizes was examined. These subwatersheds were associated with four agricultural watersheds with different climates and topography. The empirical moment scaling curves obtained using the trace moment method showed that the runoff time series exhibited a multifractal behavior, which was valid over a time scale range from one day to about three years. The multi‐fractal scaling of the runoff time series was well described by the Universal Multifractal Model. The spectral analysis (β < 1) and the order of fractional integration (H ⋍; 0) indicated that the runoff time series were conservative. The multifractal parameters, α (multifractal index) and C1(co‐dimension), were reasonably close to each other for subwatersheds within each of the watersheds and were generally similar among the four watersheds. The α values of the four watersheds were 1.10 ± 0.13, 1.61 ± 0.06,1.61 ± 0.24, and 1.63 ± 0.19. The C1values of four watersheds were 0.19 ± 0.01, 0.17 ± 0.01, 0.17 ± 0.04, and 0.11 ± 0.02. The multifractal analyses provided useful insight into the runoff time series, especially the occurrence and distribution of extreme events.