bluuebunny/crossref_metadata_2025 huggingface dataset:
Myoepithelioma with melanocytic colonization (melanocytic myoepithelioma): a case report
Authors: Bernaba Bob N , Binder Scott W , Cassarino David S
Published: May 2009

Mixed tumors of the salivary glands and the skin (also known as chondroid syringomas) contain epithelial and myoepithelial components in a chondroid to myxoid stroma. Lesions that are composed solely of cells with myoepithelial differentiation are known as myoepitheliomas. These tumors have been well described in the salivary glands and many other sites, and within the past decade, cutaneous myoepitheliomas have been described as well. Immunohistochemically, these lesions are typically positive for S‐100, cytokeratin and/or epithelial membrane antigen (EMA), with variable positivity for glial fibrillary acid protein and myogenic markers such as actin and calponin. Rare case reports have described the presence of melanocytes in mixed tumors of the salivary glands, but they have not been shown in mixed tumors or myoepitheliomas of the skin. We report a case of a cutaneous myoepithelioma with a distinct subpopulation of spindled to dendritic melanocytes, confirmed by immunohistochemical positivity for S‐100, HMB‐45 and melanoma antigen recognized by T‐cells‐1 (Mart‐1).
Nucleolin protein expression in cutaneous melanocytic lesions
Authors: Mourmouras Vasileios , Cevenini Gabriele , Cosci Elena , Epistolato Maria C. , Biagioli Maurizio , Barbagli Letizia , Luzi Pietro , Mannucci Susanna , Miracco Clelia
Published: May 2009

Background: Nucleolin is a major nucleolar argyrophilic protein involved in carcinogenesis. There are only few studies on its tissue expression in human cancer and none in melanoma. We aimed at exploring this protein and its prognostic impact in cutaneous melanocytic lesions.

Methods: We studied 193 cases including benign, dysplastic and malignant melanocytic lesions. Nuclear positivity was evaluated by immunohistochemistry and quantified by automated image analysis.

Results: Most dysplastic and malignant lesions showed high percentages of cells with abnormal patterns of nuclear positivity (Abn+N) consisting in multiple, irregular, positive dots (ID+) and a coarse, irregularly positive nucleoplasm (CNpl+) or both (ID+CNpl+). The patterns CNpl+ and/or ID+CNpl+ were never observed in benign lesions, in which ID+ were also virtually absent. Abn+N% was significantly lower in dysplastic nevi than in primary melanomas and metastases and in primary melanomas than in metastases (p < 0.05). Furthermore, Abn+N was the second powerful prognostic discriminator, after melanoma thickness, and a significantly lower survival was observed in vertical growth phase melanoma patients showing Abn+N in more than 50% of melanoma cells.

Conclusion: An altered nuclear nucleolin expression seems to accompany melanoma progression. Further investigation on nucleolin functionality and subcellular trafficking could add information on its altered role in melanoma.
Cutaneous sebaceous neoplasms as markers of Muir‐Torre syndrome: a diagnostic algorithm
Authors: Abbas Ossama , Mahalingam Meera
Published: May 2009

Sebaceous gland neoplasms such as adenoma, epithelioma, and carcinoma are uncommon cutaneous tumors. Although sporadic, their occurrence is clinically significant because of their association with Muir‐Torre syndrome (MTS). MTS is a rare autosomal dominant genodermatosis characterized by the occurrence of sebaceous gland neoplasms and/or keratoacanthomas associated with visceral malignancies that include gastrointestinal and genitourinary cancers. MTS is usually the result of germline mutation in one or more of the DNA mismatch repair (MMR) genes. MMR genes commonly implicated include MSH‐2 and MLH‐1 and, more recently, MSH‐6. Recent evidence suggests that immunohistochemistry is very sensitive and effective in detecting these defects in cutaneous tumors in MTS. In addition, the genetic instability of cutaneous and visceral tumors in MTS caused by the defects in MMR genes can also be detected, using polymerase chain reaction (PCR)‐based techniques, for microsatellite instability (MSI). Given that some sebaceous neoplasms represent cutaneous markers of MTS, what should we as dermatopathologists be advocating? Should we be looking for absence/loss of MMRs in all sebaceous neoplasms? When should we recommend assaying for MSI? This review attempts to address all of these issues with a view to streamlining the work‐up of a patient presenting for the first time with a sebaceous neoplasm and no prior personal or family history of internal malignancies.
Cervical sympathectomy causes alveolar bone loss in an experimental rat model
Authors: Kim Y. , Hamada N. , Takahashi Y. , Sasaguri K. , Tsukinoki K. , Onozuka M. , Sato S.
Published: May 2009

Background and Objective: Periodontal disease, a pathological destructive inflammatory condition, is characterized by alveolar bone loss. Recent studies have suggested a correlation between the sympathetic nervous system and bone remodeling. To confirm the importance of the sympathetic nervous system in bone resorption, we investigated the effects of superior cervical ganglionectomy and oral challenge withPorphyromonas gingivalison alveolar bone loss in rats.

Material and Methods: Rats were divided into three groups: group A underwent a sham operation as the control group; group B underwent superior cervical ganglionectomy; and group C underwent a sham operation and oral challenge withP. gingivalis. Horizontal alveolar bone loss was evaluated by measuring the distance between the cemento‐enamel junction and the alveolar bone crest. Cytokine gene expression in the gingival tissues was assessed using reverse transcription–polymerase chain reaction analyses. The furcation areas of the mandibular molars were examined histologically.

Results: Both superior cervical ganglionectomy and oral challenge withP. gingivalisresulted in accelerated alveolar bone loss. Gingival tissues in the superior cervical ganglionectomy group showed increased expression of the cytokines interleukin‐1alfa, tumor necrosis factor‐alfa and interleukin‐6. The density of neuropeptide Y‐immunoreactive fibers was decreased following superior cervical ganglionectomy. Osteoclasts were observed in the superior cervical ganglionectomy andP. gingivalis‐challenged groups.

Conclusion: Both superior cervical ganglionectomy and oral challenge withP. gingivalisinduced alveolar bone loss. These results provide new information on the occurrence of alveolar bone loss, in that both oral challenge withP. gingivalisand superior cervical ganglionectomy are important accelerating factors for alveolar bone loss. Thus, we suggest that the sympathetic nervous system is linked with the prevention of alveolar bone loss.
Expression of metalloproteinases and their tissue inhibitors in gingiva affected by hereditary gingival fibromatosis: analysis of three cases within a family
Authors: Da Ros Gonçalves L. , Oliveira G. A. P. , Borojevic R. , Otazu I. B. , Feres‐Filho E. J.
Published: May 2009

Background and Objective:  Hereditary gingival fibromatosis (HGF) is a benign disorder manifested by fibrous enlargement of keratinized gingiva. Evidence exists concerning the role of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in mediating normal and pathological processes, including HGF. Nevertheless, there are few and contradictory results on the analysis of MMPs and TIMPs transcripts in this pathology.

Material and Methods:  We studied the expression of the transcripts encoding MMP‐1, ‐2 and ‐9 and TIMP‐1 and ‐2 in gingival biopsies, obtained from three cases of HGF within a family, by semi‐quantitative reverse transcriptase‐polymerase chain reaction analysis. Samples were also processed for gelatin zymography.

Results:  Except for MMP‐9, most transcripts presented a higher level of expression in biopsies from HGF patients compared with control subjects. Accordingly, MMP‐9 gelatinase activity was detected at low and similar levels among samples. Moreover, MMP‐2 enzymatic activity was not detected at all.

Conclusion:  The mRNA expression of MMP‐1 and ‐2 and TIMP‐1 and ‐2 does not explain the gingival overgrowth presented in these cases. In addition, it is suggested that the gene expression of those molecules in the course of HGF is regulated at the translational or post‐translational level.
Nutrition and health: guidelines for dental practitioners
Authors: Palacios C , Joshipura KJ , Willett WC
Published: May 2009

Good nutrition is vital to overall health, and poor diet and a sedentary lifestyle are major causes of morbidity and mortality worldwide. Nutritional factors are implicated in many oral and systemic diseases and conditions, including obesity, hypertension, dyslipidemia, type II diabetes, cardiovascular disease, osteoporosis, dental caries and some cancers including oral cancers. This review focuses on the evidence for the relations between key nutritional factors and health. Energy intake is related to body weight and obesity, highlighting the importance of lower‐energy diets and regular physical activity for body weight maintenance and for preventing obesity. Evidence is presented for the health benefits of high quality carbohydrates, such as whole grain products, and fruits and vegetables, in reducing the risk of cardiovascular disease and cancer. The adverse effects of sugar, sweetened beverages, andtransand saturated fats on several diseases including caries, diabetes and cardiovascular disease are described. The health benefits of unsaturated fats, antioxidants, B vitamins and vitamin D in cardiovascular disease, periodontitis, cancer, and other conditions are documented. Both benefits and harmful effects of dairy product intake on health are discussed. Based on the evidence, nutritional guidelines are provided, as well as key recommendations for preventing obesity. Dentists can play a critical role in motivating and enabling healthy food choices.
Vincent McNabb, Agrarian Utopia and The Theology of Work: An exploration of the theology of the Catholic Land Association in relation to the social encyclicals Rerum Novarum and Laborem Exercens)
Authors: Kelly Joseph
Published: May 2009

The essay examines the Catholic Church's theology of work, as revealed specifically by two influential encyclicals on human work, Rerum Novarum (1891) and Laborem Exercens (1981). Both documents attracted approval for their espousal of the dignity of the worker, and Laborem Exercens in particular is said to have expounded the establishment of a dynamic new form of economic personalism in which John Paul II attempts to analyse the moral ramifications of economic activity in light of a theological vision of the human person. For all their good intentions of rationalising human materiality, both encyclicals served primarily to redress the imbalances of the employer/employee relationship, rather than to fundamentally question the philosophical and biblical anthropology of the increasingly dysfunctional nature of human work.

The Catholic Land Movement (1929 – 1939), an English agrarian community initiative that embraced the principles of Rerum Novarum, attempted in to create an entirely new theology of human work, around the principles of Distributism, Dominicanism and the arts-and-crafts movement. The ideological progress of the land colonies, and their increasing antipathy to industrialism, led them to challenge fundamentally the presumption of the need for mass employment - a position that significantly undermined the primacy of Rerum Novarum, and consequently compromised hierarchy support for their initiative, leading to the organisation's rapid decline. Despite its failure, the Catholic Land Movement nonetheless gave voice to the theologically significant possibility that the message of Genesis might not be that Man is destined for a lifetime's arduous toil.
CmtR, a cadmium‐sensing ArsR–SmtB repressor, cooperatively interacts with multiple operator sites to autorepress its transcription in Mycobacterium tuberculosis
Authors: Chauhan Santosh , Kumar Anil , Singhal Amit , Tyagi Jaya Sivaswami , Krishna Prasad H.
Published: May 2009

CmtR is a repressor of the ArsR–SmtB family from Mycobacterium tuberculosis that has been shown to sense Cd(II) and Pb(II) in Mycobacterium smegmatis. We establish here that CmtR binds cooperatively to multiple sites in M. tuberculosis DNA and protects an unusually long 90 bp AT‐rich sequence from −80 bp to +10 with respect to its own initiation codon. CmtR interacts with four hyphenated imperfect inverted repeats matching the consensus sequence TA/GTAA‐N4–5‐TT/GATA in the protected region. SDS–PAGE and formaldehyde crosslinking experiments showed that CmtR forms higher‐order oligomers (up to an octamer). The oligomerization of CmtR is in agreement with the cooperative binding of CmtR to multiple sites on DNA. Two promoters transcribe cmtR, and the major promoter physically overlaps with CmtR binding sites. Autorepression of CmtR is mediated by cooperative interaction of CmtR with multiple sites on DNA that occlude the major operon promoter. The combined results of a GFP reporter assay, an electromobility shift assay and a DNase I footprinting experiment establish that Cd(II), not Pb(II), disrupts the interaction of CmtR with DNA to de‐repress transcription of the cmtR–Rv1993c–cmtA operon in M. tuberculosis.
Inhibitor of nuclear factor‐kappaB alpha derepresses hypoxia‐inducible factor‐1 during moderate hypoxia by sequestering factor inhibiting hypoxia‐inducible factor from hypoxia‐inducible factor 1α
Authors: Shin Dong Hoon , Li Shan Hua , Yang Seung‐Won , Lee Byung Lan , Lee Myung Kyu , Park Jong‐Wan
Published: May 2009

Hypoxia and inflammation often develop concurrently in numerous diseases, and both hypoxia‐inducible factor (HIF)‐1α and nuclear factor‐kappaB (NF‐κB) are key transcription factors of stress response genes. An NF‐κB inhibitor, inhibitor of NF‐κBα (IκBα), was found to interact with factor inhibiting HIF (FIH) and to be hydroxylated by FIH. However, FIH did not functionally regulate IκBα, and the consequence of the FIH–IκBα interaction thus remains uncertain. In the present study, we tested the possibility that IκBα regulates FIH. FIH–IκBα binding was confirmed by yeast two‐hybrid and coimmunoprecipitation analyses. Functionally, IκBα expression further enhanced the transcriptional activity of HIF‐1α under hypoxic conditions. Furthermore, IκBα knockdown repressed HIF‐1α activity. Mechanistically, IκBα derepressed HIF‐1α activity by inhibiting the FIH‐mediated Asn803 hydroxylation of HIF‐1α. It was also found that IκBα activated HIF‐1α by sequestering FIH from HIF‐1α. However, the effect of IκBα on HIF‐1α activity was only observed in atmospheres containing 1% or more of oxygen. After tumor necrosis factor‐α treatment, IκBα downregulation, Asn803 hydroxylation and HIF‐1α inactivation all occurred up to 8 h, but subsided later. On the basis of these results, we propose that IκBα plays a positive regulatory role during HIF‐1‐mediated gene expression. Therefore, IκBα, owing to its interactions with NF‐κB and HIF‐1α, may play a pivotal role in the crosstalk between the molecular events that underlie inflammatory and hypoxic responses.
Hepatocyte growth factor activator is a serum activator of single‐chain precursor macrophage‐stimulating protein
Authors: Kawaguchi Makiko , Orikawa Hiroshi , Baba Takashi , Fukushima Tsuyoshi , Kataoka Hiroaki
Published: May 2009

Macrophage‐stimulating protein (MSP) is a plasma protein that circulates as a single‐chain proform. It acquires biological activity after proteolytic cleavage at the Arg483–Val484 bond, a process in which serum and cell surface serine proteinases have been implicated. In this article, we report that hepatocyte growth factor activator (HGFA), a serum proteinase which activates hepatocyte growth factor in response to tissue injury, may have a critical role in the activation of pro‐MSP. In vitro analysis has revealed that human HGFA efficiently cleaves human pro‐MSP at the physiological activation site without further degradation, resulting in biologically active MSP, as measured by the chemotactic response and MSP‐induced morphological change of peritoneal macrophages. The processing of pro‐MSP by HGFA is 10‐fold more efficient than processing by factor XIa. To search for a role of HGFA in pro‐MSP activation, we analyzed the processing of mouse pro‐MSP in sera from HGFA‐knockout (HGFA−/−) mice. The proform of MSP was the predominant molecular form in the plasma of both wild‐type and HGFA−/− mice. In wild‐type sera, endogenous pro‐MSP was progressively converted to the mature two‐chain form during incubation at 37 °C. However, this conversion was significantly impaired in sera from HGFA−/− mice. The addition of recombinant HGFA to HGFA‐deficient serum restored pro‐MSP convertase activity in a dose‐dependent manner, and a neutralizing antibody to HGFA significantly reduced the conversion of pro‐MSP in wild‐type serum. Moreover, initial infiltration of macrophages into the site of mechanical skin injury was delayed in HGFA−/− mice. We suggest that HGFA is a major serum activator of pro‐MSP.
Alanine screening of the intracellular loops of the human bradykinin B2 receptor – effects on receptor maintenance, G protein activation and internalization
Authors: Faussner Alexander , Wennerberg Goeran , Schüssler Steffen , Feierler Jens , Seidl Cornelia , Jochum Marianne , Proud David
Published: May 2009

The bradykinin B2 receptor is coupled to G protein Gq/11 and becomes sequestered into intracellular compartments after activation. To more closely define the receptor sequences involved in these processes and their functions, we systematically mutated all three intracellular loops (ICLs), either as point mutations or in groups of three to five amino acids to Ala, obtaining a total of 14 mutants. All constructs were stably expressed in HEK 293 cells and, with the exception of triple mutant DRY → AAA, retained the ability to specifically bind [3H]bradykinin. The binding affinities at 4 or 37 °C of several mutants differed considerably from those determined for the wild‐type receptor, indicating an allosteric connection between the conformation of the binding site and that of the ICLs. Mutations in ICL‐1 strongly reduced surface expression without affecting G protein signaling or [3H]bradykinin internalization. Two cluster mutants in the middle of ICL‐2 containing basic residues displayed considerably reduced potencies, whereas two mutations in ICL‐3 resulted in receptor conformations that were considered to be semi‐active, based on the observation that they responded with phosphoinositide hydrolysis to compounds normally considered to be antagonists. This, and the fact that a cluster mutant at the C‐terminal end of ICL‐3 was signaling incompetent, hint at the involvement of ICL‐2 and ICL‐3 in Gq/11 activation, albeit with different functions. None of the mutants displayed reduced ligand‐induced receptor internalization, indicating that the loops are not essential for this process. No conclusion could be drawn, however, with regard to the role of the DRY sequence, as the corresponding triplet mutation lacked binding capability.
RESPONSE SURFACE OPTIMIZATION FOR CLARIFICATION OF WHITE PITAYA JUICE USING A COMMERCIAL ENZYME
Authors: NUR ‘ALIAA A.R. , SITI MAZLINA M.K. , TAIP F.S. , LIEW ABDULLAH A.G.
Published: May 2009

Raw white pitaya (Hylocereus undatus) juice is very cloudy and viscous. These physical properties lead to the use of enzymatic treatment to clarify the juice. The aim of this study was to obtain the optimum process conditions for enzymatic clarification using response surface methodology (RSM). White pitaya juice was treated with pectinase enzyme (Pectinex Ultra SP‐L) at different maceration times (20–100 min), reaction temperatures (30–50C) and enzyme concentrations (0.01–0.1%). These three variables were used as independent variables whose effects on yield, viscosity, clarity and color were evaluated. From the RSM analysis, the recommended enzymatic treatment condition from the study was found at 0.06% enzyme concentration at 49C for 40 min.

PRACTICAL APPLICATIONS

This paper describes an optimization study on enzymatic clarification of white pitaya juice. The aim was to reduce juice viscosity and to increase juice yield, clarity and color via enzymatic degradation of polysaccharides in the white pitaya. This work recommended an optimal enzymatic treatment for clarification of white pitaya juice using Pentinex Ultra SP‐L for commercialization.
ALGINATE GELS: II. STABILITY AT DIFFERENT PROCESSING CONDITIONS
Authors: ROOPA B.S. , BHATTACHARYA SUVENDU
Published: May 2009

Wet heating processes, such as boiling in water and steaming for different periods (5, 10, 20, 30, 45 and 60 min), were employed to know the stability of alginate gels along with obtaining the kinetics of textural parameters. A compression test up to a strain of 0.8 was employed on unprocessed and processed gels to know the different textural parameters (fracture force/energy, compression energy, peak stress, firmness and linear elastic limit) that characterized the mechanical behavior. These gels are heat stable and thermoirreversible in nature, exhibiting a marginal decrease in volume after the wet heat treatments. The order of kinetics of textural parameters is less than 1 and exhibits fractional values. Fracture force/energy, compression energy and peak stress decreased with the time of treatment, whereas firmness and strain at failure increased. A three‐parameter nonlinear model has been proposed to predict the force values during compression of food gels.

PRACTICAL APPLICATIONS

The alginate gels along with fruit and vegetable extracts can form a gel with adequate solid characteristics to be suitable as a convenience food. These gels can maintain their integrity and show resistance to wet heat treatments, like boiling in water and steaming, such that they are suitable for the purpose of product development along with other food ingredients, which requires further processing steps like blanching, pasteurization and sterilization.
Simulating Piecewise‐Linear Surface Water and Ground Water Interactions with MODFLOW
Authors: Zaadnoordijk Willem Jan
Published: May 2009

The standard MODFLOW packages offer limited capabilities to model piecewise‐linear boundary conditions to describe ground water–surface water interaction. Specifically, MODFLOW is incapable of representing a Cauchy‐type boundary with different resistances for discharge or recharge conditions. Such a more sophisticated Cauchy boundary condition is needed to properly represent surface waters alternatively losing water through the bottom (high resistance) or gaining water mostly near the water surface (low resistance). One solution would be to create a new package for MODFLOW to accomplish this. However, it is also possible to combine multiple instances of standard packages in a single cell to the same effect. In this specific example, the general head boundary package is combined with the drain package to arrive at the desired piecewise‐linear behavior. In doing so, the standard USGS MODFLOW version can be used without any modifications at the expense of a minor increase in preprocessing and postprocessing and computational effort. The extra preprocessing for creating the input and extra postprocessing to determine the water balance in terms of the physical entities from the MODFLOW cell fluxes per package can be taken care of by a user interface.
Writing Analytic Element Programs in Python
Authors: Bakker Mark , Kelson Victor A.
Published: May 2009

The analytic element method is a mesh‐free approach for modeling ground water flow at both the local and the regional scale. With the advent of the Python object‐oriented programming language, it has become relatively easy to write analytic element programs. In this article, an introduction is given of the basic principles of the analytic element method and of the Python programming language. A simple, yet flexible, object‐oriented design is presented for analytic element codes using multiple inheritance. New types of analytic elements may be added without the need for any changes in the existing part of the code. The presented code may be used to model flow to wells (with either a specified discharge or drawdown) and streams (with a specified head). The code may be extended by any hydrogeologist with a healthy appetite for writing computer code to solve more complicated ground water flow problems.
Well Development by Jetting Using Coiled Tubing and Simultaneous Pumping
Authors: Rosberg Jan‐Erik , Bjelm Leif
Published: May 2009

During flow testing of a deep, 1927‐m, gravel packed screen completed well, it became apparent that well development was needed to increase productivity. A hydrojetting system using coiled tubing in combination with simultaneous pumping was developed and tested and found to be successful. To verify whether the jetting improved the well, the results of a pumping test conducted before and after the jetting operation are compared. In addition, flowmeter logging and hydraulic properties obtained from pumping tests conducted during the jetting operation were also used to verify the improvements. Hydrojetting in combination with simultaneous pumping proved to be an effective cleaning method. After 100 min of pumping, around 110 m less drawdown and 15 L/s higher average flow rate were obtained compared to the values before the jetting operation. The skin factor was positive before the jetting operation and negative thereafter, thus providing additional evidence of improvements of the well. The flowmeter data also confirmed the improvements and were valuable in optimizing the jetting operation. It was also found, from the short‐term pumping tests conducted during the jetting operation, that the Hantush–Jacob method for leaky confined aquifers is a valuable indicator of the well development. The combination of methods used for the well development in this case can easily be applied on other deep well projects to obtain a controlled and time‐efficient well development.
Concentration Profiles in Screened Wells under Static and Pumped Conditions
Authors: McDonald John P. , Smith Ronald M.
Published: May 2009

Purge and pump samples from screened wells reflect concentration averaging and contaminant redistribution by wellbore flow. These issues were assessed in a screened well at the Hanford Site by investigating the vertical profile of a technetium‐99 plume in a conventional well under static and pumped conditions. Specific conductance and technetium‐99 concentrations were well correlated, and this enabled measurement of specific conductance to be used as a surrogate for technetium‐99 concentration. Time‐series measurements were collected during purging from three specific conductance probes installed in the well at 1.2, 3.1, and 4.9 m below the static water level in a 7.7‐m‐deep screened well. The vertical contaminant profile adjacent to the well in the aquifer was calculated using the concentration profile in the well during pumping, the pumping flow rate, and a wellbore flow and mixing model. The plume was found to be stratified in the aquifer—the highest concentrations occurred adjacent to the upper part of the screened interval. The purge and pump sample concentrations were 41% to 58% of the calculated peak concentration in the aquifer. Plume stratification in the aquifer adjacent to the well screen became more pronounced as pumping continued. Extended pumping may have partially reversed the effect of contaminant redistribution in the aquifer by wellbore flow and allowed the stratification of the plume to be more observable. It was also found that the vertical profile of contamination in the well under static (i.e., nonpumping conditions) was not representative of the profile in the aquifer. Thus, passive or micropurge sampling techniques, which sample the wellbore water at different depths, would not yield results representative of the aquifer in this well.
Estimating Persistent Mass Flux of Volatile Contaminants from the Vadose Zone to Ground Water
Authors: Truex M.J. , Oostrom M. , Brusseau M.L.
Published: May 2009

Contaminants may persist for long time periods within low permeability portions of the vadose zone where they cannot be effectively treated and are a potential continuing source of contamination to ground water. Setting appropriate vadose zone remediation goals typically requires evaluating these persistent sources in terms of their impact on meeting ground water remediation goals. Estimating the impact on ground water can be challenging at sites with low aqueous recharge rates where vapor‐phase movement is the dominant transport process in the vadose zone. Existing one‐dimensional approaches for simulating transport of volatile contaminants in the vadose zone are considered and compared to a new flux‐continuity‐based assessment of vapor‐phase contaminant movement from the vadose zone to the ground water. The flux‐continuity‐based assessment demonstrates that the ability of the ground water to move contaminant away from the water table controls the vapor‐phase mass flux from the vadose zone across the water table. Limitations of these approaches are then discussed with respect to the required assumptions and the need to incorporate three‐dimensional processes when evaluating vapor‐phase transport from the vadose zone to the ground water. The carbon tetrachloride plume at the U.S. Department of Energy Hanford Site is used as the example site where persistent vadose zone contamination needs to be considered in the context of ground water remediation.
Nanocomposite Edible Films from Mango Puree Reinforced with Cellulose Nanofibers
Authors: Azeredo Henriette M.C. , Mattoso Luiz Henrique C. , Wood Delilah , Williams Tina G. , Avena‐Bustillos Roberto J. , McHugh Tara H.
Published: May 2009

ABSTRACT:  Cellulose nanoreinforcements have been used to improve mechanical and barrier properties of biopolymers, whose performance is usually poor when compared to those of synthetic polymers. Nanocomposite edible films have been developed by adding cellulose nanofibers (CNF) in different concentrations (up to 36 g/100 g) as nanoreinforcement to mango puree based edible films. The effect of CNF was studied in terms of tensile properties, water vapor permeability, and glass transition temperature (Tg) of the nanocomposite films. CNF were effective in increasing tensile strength, and its effect on Young's modulus was even more noticeable, especially at higher concentrations, suggesting the formation of a fibrillar network within the matrix. The addition of CNF was also effective to improve water vapor barrier of the films. Its influence on Tg was small but significant. The study demonstrated that the properties of mango puree edible films can be significantly improved through CNF reinforcement.
Documenting discontent: Struggles for recognition in the Purari Delta of Papua New Guinea
Authors: Bell Joshua A.
Published: May 2009

Within the context of the Purari Delta’s transforming materialities of resource extraction, and the legacy of the Tom Kabu iconoclastic modernist movement (1946–69), I examine the processes of materialisation bound up with two related but different things: heirlooms (eve uku) and documents (Incorporated Land Group (ILG) forms).Eve uku(‘hand head’) lie within a continuum of things (names, relations, totemic ancestral spirit‐beings and sites in the environment) through which ancestral actions are shown to have happened, and descent groups’ identities manifest. However, given the ambiguous status of the traditional past among the I’ai, the power of these forms is circumscribed to the village thus making them ineffectual tokens in the bid to secure royalties from resource extraction. Instead, highly coveted documents known as ILG certificates have emerged as efficacious things by which royalties can be secured. Examining these certificates as objects, I investigate how these documents help materialise anew descent groups, communities’ relations to their environment and thus their aspirations for development with its attending materialities. The problem for the I’ai, however, remains how to obtain these documents and, as witheve uku, how to control them.
A personal narrative of particular things:Tevau(feather money) from Santa Cruz, Solomon Islands
Authors: Bonshek Elizabeth
Published: May 2009

In October 2006, Salome Samou, from Santa Cruz Island, Solomon Islands, visited the British Museum, London, to see the collections from her home island. This paper presents her response to thetevauin the collection (frequently referred to as ‘feather money’).Tevauare objects of prestige and value, formerly used in a regional network of exchange. They were especially important in bridewealth payments, but have not been used on Santa Cruz Island since the 1980s. Today, Samou wants to revive their use, a re‐introduction that reflects a linkage oftevauand their manufacture to contemporary ideas of social identity. This paper explores Samou’s interaction with thetevauin the collection, including past interpretations of their use. For Samou, the process of viewing thetevauproduced a narrative that embraced personal memories as well as challenged perspectives on past cultural and social practices. I discuss how these particular objects materialise transformed, and transforming, regimes of value.
Materialising the king: The royal funeral of King Tāufa`āhau Tupou IV of Tonga
Authors: Veys Fanny Wonu
Published: May 2009

The arrival of the body of King Tāufa‘āhau Tupou IV, in Tonga on 12 September 2006, prompted complex funerary rites modelled on those of the previous monarch, Queen Sālote. Instead of looking at how funerals reinforce kinship ties or what the effective cost is of the objects exchanged, I concentrate on the presented objects, which formed the focal point of the funerary rites. In doing so, I engage withKeane (2005: 184)who asserts the relevance of semiotics in answering the question: ‘How can we both understand things and do full justice to their materiality?’ I argue that traditional prestigious objects (barkcloth, mats, baskets and coconut oil), ‘modern‐times’ valuables (flower garlands, flower baskets, and crocheted bed spreads), and contemporary objects (cakes wrapped in cling film, screens with chocolate, plastic baskets filled with bags of crisps, chocolate and sweets), materialise qualities the deceased king embodied as a descendant of a mythical ruler, as the fourth king in the modern Christian dynasty and as a contemporary ruler who reformed both education and economy. A consequence of materialising qualities is that they become contingently bound up with other qualities (Keane 2005: 188). I thus concentrate on those objects where the bundling of qualities is realised visually, examining how barkcloth, fine mats, baskets and coconut oil embody female generative power, protecting, controlling and linking qualities. It is the qualities of the objects bundled in the matter of the objects themselves that make some objects matter more than others.
Implicit Large Eddy Simulation of Two-Dimensional Homogeneous Turbulence Using Weighted Compact Nonlinear Scheme
Authors: Ishiko Keiichi , Ohnishi Naofumi , Ueno Kazuyuki , Sawada Keisuke
Published: May 2009

For the aim of computing compressible turbulent flowfield involving shock waves, an implicit large eddy simulation (LES) code has been developed based on the idea of monotonically integrated LES. We employ the weighted compact nonlinear scheme (WCNS) not only for capturing possible shock waves but also for attaining highly accurate resolution required for implicit LES. In order to show that WCNS is a proper choice for implicit LES, a two-dimensional homogeneous turbulence is first obtained by solving the Navier–Stokes equations for incompressible flow. We compare the inertial range in the computed energy spectrum with that obtained by the direct numerical simulation (DNS) and also those given by the different LES approaches. We then obtain the same homogeneous turbulence by solving the equations for compressible flow. It is shown that the present implicit LES can reproduce the inertial range in the energy spectrum given by DNS fairly well. A truncation of energy spectrum occurs naturally at high wavenumber limit indicating that dissipative effect is included properly in the present approach. A linear stability analysis for WCNS indicates that the third order interpolation determined in the upwind stencil introduces a large amount of numerical viscosity to stabilize the scheme, but the same interpolation makes the scheme weakly unstable for waves satisfying kΔx≈1. This weak instability results in a slight increase in the energy spectrum at high wavenumber limit. In the computed result of homogeneous turbulence, a fair correlation is shown to exist between the locations where the magnitude of ∇×ω becomes large and where the weighted combination of the third order interpolations in WCNS deviates from the optimum ratio to increase the amount of numerical viscosity. Therefore, the numerical viscosity involved in WCNS becomes large only at the locations where the subgrid-scale viscosity can arise in ordinary LES. This suggests the reason why the present implicit LES code using WCNS can resolve turbulent flowfield reasonably well.
Natural Convection in an Anisotropic Porous Enclosure Due to Nonuniform Heating From the Bottom Wall
Authors: Kumar Ashok , Bera P.
Published: May 2009

A comprehensive numerical investigation on the natural convection in a hydrodynamically anisotropic porous enclosure is presented. The flow is due to nonuniformly heated bottom wall and maintenance of constant temperature at cold vertical walls along with adiabatic top wall. Brinkman-extended non-Darcy model, including material derivative, is considered. The principal direction of the permeability tensor has been taken oblique to the gravity vector. The spectral element method has been adopted to solve numerically the governing conservative equations of mass, momentum, and energy by using a stream-function vorticity formulation. Special attention is given to understand the effect of anisotropic parameters on the heat transfer rate as well as flow configurations. The numerical experiments show that in the case of isotropic porous enclosure, the maximum rates of bottom as well as side heat transfers (Nub and Nus) take place at the aspect ratio, A, of the enclosure equal to 1, which is, in general, not true in the case of anisotropic porous enclosures. The flow in the enclosure is governed by two different types of convective cells: rotating (i) clockwise and (ii) anticlockwise. Based on the value of media permeability as well as orientation angle, in the anisotropic case, one of the cells will dominate the other. In contrast to isotropic porous media, enhancement of flow convection in the anisotropic porous enclosure does not mean increasing the side heat transfer rate always. Furthermore, the results show that anisotropy causes significant changes in the bottom as well as side average Nusselt numbers. In particular, the present analysis shows that permeability orientation angle has a significant effect on the flow dynamics and temperature profile and consequently on the heat transfer rates.
Heat Transfer and Fluid Flow Characteristics in Supercritical Pressure Water
Authors: Licht Jeremy , Anderson Mark , Corradini Michael
Published: May 2009

A series of integral heat transfer measurements in a square annular flow passage was performed for bulk water temperatures of 175–400°C with upward mass velocities of 300 kg/m2 s and 1000 kg/m2 s and heat fluxes of 0, 200 kW/m2, and 440 kW/m2, all at a pressure of 25 MPa. Mean and turbulent velocities measured with a two-component laser Doppler velocimetry system along with simulations using the computational fluid dynamics (CFD) code FLUENT were used to explain the deterioration and enhancement of heat transfer in supercritical pressure water. At low mass velocities, the integral heat transfer measurements exhibited large localized wall temperature spikes that could not be accurately predicted with Nusselt correlations. Detailed mean and turbulent velocities along with FLUENT simulations show that buoyancy effects cause a significant reduction in turbulent quantities at a radial location similar to what is the law of the wall region for isothermal flow. At bulk temperatures near the pseudocritical temperature, high mass velocity integral heat transfer measurements exhibited an enhanced heat transfer with a magnitude dependent on the applied heat flux. Measured mean and turbulent velocities showed no noticeable changes under these conditions. FLUENT simulations show that the integrated effects of specific heat can be used to explain the observed effects. The experimentally measured heat transfer and local velocity data also serve as a database to compare existing CFD models, such as Reynolds-averaged Navier-Stokes (RANS) equations and possibly even large Eddy simulations (LES) and direct numerical simulations (DNS). Ultimately, these measurements will aid in the development of models that can accurately predict heat transfer to supercritical pressure water.
Heat Transfer and Pressure Drop Correlations for Square Channels With 45 Deg Ribs at High Reynolds Numbers
Authors: Rallabandi Akhilesh P. , Yang Huitao , Han Je-Chin
Published: May 2009

Systematic experiments are conducted to measure heat transfer enhancement and pressure loss characteristics on a square channel (simulating a gas turbine blade cooling passage) with two opposite surfaces roughened by 45 deg parallel ribs. Copper plates fitted with a silicone heater and instrumented with thermocouples are used to measure regionally averaged local heat transfer coefficients. Reynolds numbers studied in the channel range from 30,000 to 400,000. The rib height (e) to hydraulic diameter (D) ratio ranges from 0.1 to 0.18. The rib spacing (p) to height ratio (p/e) ranges from 5 to 10. Results show higher heat transfer coefficients at smaller values of p/e and larger values of e/D, though at the cost of higher friction losses. Results also indicate that the thermal performance of the ribbed channel falls with increasing Reynolds numbers. Correlations predicting Nusselt number (Nu) and friction factor (f¯) as a function of p/e, e/D, and Re are developed. Also developed are correlations for R and G (friction and heat transfer roughness functions, respectively) as a function of the roughness Reynolds number (e+), p/e, and e/D.
Thermostructural Design of a Flying Winglet Experimental Structure for the EXPERT Re-entry Test
Authors: Ferraiuolo M. , Riccio A. , Gigliotti M. , Tescione D. , Gardi R. , Marino G.
Published: May 2009

Within the framework of the European Experimental Re-entry Test Bed (EXPERT) Program, aimed at improving the understanding of physical phenomena occurring during the return of space vehicles from space to earth, the design of a flying winged experimental payload has been performed in order to assess the thermomechanical behavior and resistance of ultrahigh temperature ceramics (UHTC) in real flight aerothermal environment. The EXPERT flying winglet article is intended to reproduce such conditions. Particular interest covers the design of the interfaces between the UHTC winglet and the EXPERT capsule thermal protection systems since thermal stresses arise during the re-entry phase. The fixation of the winglet to the capsule is achieved by means of dedicated bolts that must tolerate mechanical loads occurring at the first stages of the flight, that is, lift-off, ascent, and separation stages. The thermostructural design is performed by employing ANSYS/Workbench finite element commercial code; simulations take into account transient thermostructural loading conditions, the elastic-fragile behavior of the ceramic materials, and the temperature dependent elastic-plastic behavior of the capsule thermal protection systems. In the postprocessing phase, UHTC critical areas have been identified by following two different approaches. The first approach is deterministic and consists in applying a maximum stress criterion, the stress at a node is compared with the temperature dependent strength at that node. The second approach, which is commonly employed for elastic-fragile materials, is probabilistic and consists in applying a Weibull-like failure criterion. Thermal and structural analyses simulating the re-entry phase have demonstrated that the maximum stresses and temperatures evaluated do not exceed their corresponding limits. Then, a configuration respecting all the requirements of the design has been identified, and its thermal and mechanical performances are discussed in detail.
Model of Radiation and Heat Transfer in Laser-Powder Interaction Zone at Selective Laser Melting
Authors: Gusarov A. V. , Yadroitsev I. , Bertrand Ph. , Smurov I.
Published: May 2009

A model for coupled radiation transfer and thermal diffusion is proposed, which provides a local temperature field. Single-line scanning of a laser beam over a thin layer of metallic powder placed on a dense substrate of the same material is studied. Both the laser beam diameter and the layer thickness are about 50 μm. The typical scanning velocity is in the range of 10–20 cm/s. An effective volumetric heat source is estimated from laser radiation scattering and absorption in a powder layer. A strong difference in thermal conductivity between the powder bed and dense material is taken into account. The above conditions correspond to the technology of selective laser melting that is applied to build objects of complicated shape from metallic powder. Complete remelting of the powder in the scanned zone and its good adhesion to the substrate ensure fabrication of functional parts with mechanical properties close to the ones of the wrought material. Experiments with single-line melting indicate that an interval of scanning velocities exists, where the remelted tracks are uniform. The tracks become “broken” if the scanning velocity is outside this interval. This is extremely undesirable and referred to as the “balling” effect. The size and the shape of the melt pool and the surface of the metallurgical contact of the remelted material to the substrate are analyzed in relation to the scanning velocity. The modeling results are compared with experimental observation of laser tracks. The experimentally found balling effect at scanning velocities above ∼20 cm/s can be explained by the Plateau–Rayleigh capillary instability of the melt pool. Two factors destabilize the process with increasing the scanning velocity: increasing the length-to-width ratio of the melt pool and decreasing the width of its contact with the substrate.
Tomographic Characterization of a Semitransparent-Particle Packed Bed and Determination of its Thermal Radiative Properties
Authors: Haussener S. , Lipiński W. , Petrasch J. , Wyss P. , Steinfeld A.
Published: May 2009

A two-phase medium consisting of densely packed large nonspherical semitransparent particles in a transparent fluid is considered. Its 3D digital geometry is obtained by computer tomography and employed to numerically calculate its porosity, specific surface, pore and particle size distributions, and the representative elementary volume for continuum domain. The collision-based Monte Carlo method is applied to calculate the probability distribution functions for attenuation path length and direction of incidence at the fluid-solid interface for each phase, which, in turn, are used to derive the extinction and scattering coefficients and the scattering phase functions. The methodology is applied to a packed bed of CaCO3 particles, used in industrially relevant high-temperature processes. Spectral and directional dependencies of the radiative properties are analyzed.