bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation of PIT-Free Hydrogen-Terminated Si(111) in
Deoxygenated Ammonium Fluoride
Authors: Wade Christopher P. , Chidsey Christopher E. D.
Published: April 2011

We show by ex-situ STM that pit-free H-Si(111) surfaces can
be prepared by immersion of pre-oxidized Si(111) in deoxygenated 40%
NH4F for 15 minutes. In contrast, H-Si(111) prepared in
air-saturated 40% NH4F for 15 minutes results in small etch pits
randomly covering ca. 1% of the surface. Added dioxygen,
shorter etching times or stirring of the air-saturated etch solution
increase the etch pit density. Dissolved oxygen is responsible for the
initiation of etch pits on the (111) monohydride terraces. The reaction
between dissolved oxygen and the H-Si bond of the (111) terrace is limited
by mass transport of dissolved oxygen to the silicon surface. A proposed
reaction mechanism of dissolved oxygen with H-Si is briefly mentioned, which
explains not only etch pit initiation in ammonium fluoride but also the
oxidation of hydrogenterminated silicon in wet, oxygenated environments. The
results presented here for H-Si(111) lead to a greater understanding of the
wet oxidation and etching processes of this important model surface.
Influence of the Implant Diameter With Different Sizes of Hexagon: Analysis by 3-Dimensional Finite Element Method
Authors: Pellizzer Eduardo Piza , Verri Fellippo Ramos , de Moraes Sandra Lúcia Dantas , Falcón-Antenucci Rosse Mary , de Carvalho Paulo Sérgio Perri , Noritomi Pedro Yoshito
Published: April 2011

The aim of this study was to evaluate the stress distribution in implants of regular platforms and of wide diameter with different sizes of hexagon by the 3-dimensional finite element method. We used simulated 3-dimensional models with the aid of Solidworks 2006 and Rhinoceros 4.0 software for the design of the implant and abutment and the InVesalius software for the design of the bone. Each model represented a block of bone from the mandibular molar region with an implant 10 mm in length and different diameters. Model A was an implant 3.75 mm/regular hexagon, model B was an implant 5.00 mm/regular hexagon, and model C was an implant 5.00 mm/expanded hexagon. A load of 200 N was applied in the axial, lateral, and oblique directions. At implant, applying the load (axial, lateral, and oblique), the 3 models presented stress concentration at the threads in the cervical and middle regions, and the stress was higher for model A. At the abutment, models A and B showed a similar stress distribution, concentrated at the cervical and middle third; model C showed the highest stresses. On the cortical bone, the stress was concentrated at the cervical region for the 3 models and was higher for model A. In the trabecular bone, the stresses were less intense and concentrated around the implant body, and were more intense for model A. Among the models of wide diameter (models B and C), model B (implant 5.00 mm/regular hexagon) was more favorable with regard to distribution of stresses. Model A (implant 3.75 mm/regular hexagon) showed the largest areas and the most intense stress, and model B (implant 5.00 mm/regular hexagon) showed a more favorable stress distribution. The highest stresses were observed in the application of lateral load.
Distribution of α‐ and δ‐Tocopherols in Seminal Plasma and Sperm Fractions of Men With Normal and Abnormal Semen Parameters
Authors: Moretti Elena , Castellini Cesare , Mourvaki Evangelia , Capitani Serena , Geminiani Michela , Renieri Tommaso , Collodel Giulia
Published: April 2011

ABSTRACT: The aim of this study was to investigate the presence of the different isoforms of tocopherol (T) in seminal plasma (P) and in the sperm fractions of individuals with abnormal (group 1) and normal (group 2) sperm parameters; the relationships between these isoforms and conventional sperm parameters were also explored. Two vitamin E homologues, α‐T and δ‐T, were identified in the semen of all participants. Although α‐T and δ‐T concentrations were similar in the semen of the 2 groups, group 1 showed a lower α‐T ratio (S/P) (0.90 vs. 1.20, P < .001) and δ‐T ratio (0.86 vs 1.13, P = .007) than group 2. In addition, both T ratios were correlated with the percentage of viable cells, detected by eosin staining. These results suggested that α‐T and δ‐T are not homogeneously distributed in the semen fractions; in normal semen they are more concentrated in the sperm membrane, whereas in abnormal semen the damaged sperm cells may release both Ts in the plasma. To verify whether sperm membrane breakage could alter α‐T and δ‐T distribution between the seminal plasma and the spermatozoa, normal sperm samples were sonicated; after sonication a consistent sperm plasma membrane fragmentation, highlighted by transmission electron microscopy, and a concomitant release of α‐T and δ‐T were observed. In conclusion, the Ts coupled directly with the sperm membrane seem to play the main protective role in the semen, and the release of α‐T and δ‐T in the P fraction is probably an index of lower antioxidant power and sperm quality.
Chromosomal Abnormalities in 2 Cases of Testicular Failure
Authors: Chen Xueyan , Raca Gordana , Laffin Jennifer , Babaian Kara N. , Williams Daniel H.
Published: April 2011

ABSTRACT: This study investigated the underlying chromosomal abnormalities of testicular failure using molecular cytogenetic analysis. We report 2 cases of rare genetic anomalies that resulted in hypogonadism. The first patient presented with severe hypogonadism. Chromosome analysis revealed a mosaic 46,X,r(Y) (p11.3q11.23)/45,X karyotype, with a ring Y chromosome. A Y chromosome microdeletion assay showed a deletion in the azoospermia factor a region. The second patient presented with infertility and nonobstructive azoospermia. Cytogenetic and fluorescent in situ hybridization analysis revealed a 47,XY,+mar.ish i(15) (D15Z1++,SNRPN2,PML2) karyotype, with a small supernumerary chromosome derived from chromosome 15. These results emphasize the need for molecular cytogenetic evaluation in patients with testicular failure before using advanced reproductive techniques.
Development of Bovine Fetal Testis Tissue After Ectopic Xenografting in Mice
Authors: Rodriguez‐Sosa Jose R. , Rathi Rahul , Wang Zhongde , Dobrinski Ina
Published: April 2011

ABSTRACT:Testis tissue xenografting represents a versatile model to study testis biology, and to preserve fertility in immature animals. To evaluate whether bovine fetal testes can mature when grafted into mouse hosts, small fragments of testes from midgestation (125 to 145 days of gestation) bovine fetuses were grafted ectopically into immunodeficient castrated male mice. At grafting, donor tissue displayed the typical seminiferous cords composed of gonocytes and primitive Sertoli cells. At 5 or 10 months after grafting, weight of the seminal vesicles in recipient mice was indicative of production of bioactive testosterone by xenografts. Xenografts showed similar development regardless of donor age. At 5 months, tubule formation occurred but germ cell differentiation had not proceeded beyond the spermatogonia stage. At 10 months, an increase in tubule size was evident and pachytene spermatocytes were observed as the most advanced type of germ cells in the xenografts of 2 donors. The number of tubules with germ cells was reduced in xenografts compared to donor tissue, but at 10 months the number of germ cells per tubule was higher than in donors. Germ cell proliferation was similar in donor tissue and xenografts. However, Sertoli cells showed a higher proliferation rate in xenografts collected at 5 months than in donor fetal testes and xenografts collected at 10 months. Sertoli cells in xenografts showed a progressive but incomplete loss of expression of Müllerian inhibiting substance and weak androgen receptor expression, indicating an incomplete Sertoli cell maturation. In conclusion, fetal testis tissue developed partially, qualitatively similar to pubertal testes in situ.
Genetic Regulation of Prostate Development
Authors: Meeks Joshua J. , Schaeffer Edward M.
Published: April 2011

ABSTRACT: Prostatic development is a dynamic process in which basic mechanisms of epithelial outgrowth and epithelial‐mesenchymal interaction are initiated by androgens and androgen receptor signaling. Even in adulthood, the prostate's function remains tightly regulated by androgens—without them, pathologic diseases, including hyperplastic and malignant growth that together plague nearly 50% of aging males, do not occur. Unraveling the etiology of these pathologic processes is a complex and important goal. In fact, many insights into these processes have come from an intimate understanding of the complex signaling networks that regulate physiologic prostatic growth in development. This review aims to highlight important key molecules such as Nkx3.1, sonic hedgehog, and Sry box 9, as well as key signaling pathways including the fibroblast growth factor and wingless pathways. These molecules and pathways are critical for prostate development with both known and postulated roles in prostatic pathology.
Ejaculate Traits and Sperm Cryopreservation in the Endangered Baird's Tapir (Tapirus bairdii)
Authors: Pukazhenthi Budhan S. , Togna Gina Della , Padilla Luis , Smith Diorene , Sanchez Carlos , Pelican Katey , Sanjur Oris I.
Published: April 2011

ABSTRACT: There is little information on the reproductive biology of the male Baird's tapir (Tapirus bairdii). In this study, we characterized the ejaculate traits and evaluated the efficacy of 2 cryodiluents on sperm cryosurvival. Ejaculates were assessed for volume, pH, sperm motility, forward progression, osmolality, sperm concentration, sperm morphology, and acrosomal integrity. For cryopreservation, ejaculates with >50% total sperm motility were washed, and sperm pellets were resuspended in either Botu‐Crio (CryoVital, Grandau, Germany) or INRA 96 containing 2% egg yolk and 2.5% each of methyl‐ and dimethylformamide (INRA 96), and they were cryopreserved over liquid nitrogen vapor. Thawed samples were incubated in vitro (25°C) and evaluated for percent total sperm motility, forward progression, and acrosomal integrity at hourly intervals for 4 hours. Spermic ejaculates were obtained from all males, and the mean seminal volume, sperm concentration per milliliter, percent sperm motility, progressive status, and percent morphologically normal cells were 20.4 ± 4.3 mL, 101.2 ± 24.0 × 106/mL, 46.1% ± 5.0%, 2.9 ± 0.1, and 6.9% ± 1.4%, respectively. There was a positive significant correlation between percent normal sperm and animal age (r = 0.66; P < .004). Cryopreservation in either Botu‐Crio or INRA 96 resulted in a decline (P < .05) in percent sperm motility and acrosomal integrity. Sperm forward progression remained unaffected immediately after thawing in INRA 96 but continued to decline over time. These results characterize, for the first time, the ejaculate traits of the tapir; demonstrate that tapir spermatozoa can be cryopreserved in diluents containing amides alone or in combination with glycerol; and provide fundamental information critical for development of assisted reproductive technologies for the Baird's tapir.
Modeling the Inactivation of Microorganisms Occluded in Effluent Wastewater Particles to Enhance Operation of Filtration and Disinfection Systems
Authors: Camarillo Mary Kay , Loge Frank J. , Darby Jeannie L. , Ginn Timothy R. , Başağaoğlu Hakan , Foglia Laura
Published: April 2011

In disinfection systems, incomplete penetration of chlorine into effluent wastewater particles can result in a residual population of viable microorganisms. In this work, a combined experimental and numerical approach was used to quantify inactivation of microorganisms in effluent particles and identify combinations of particle removal and chlorine dose that would result in a reduction of occluded microorganisms for six full‐scale facilities in the United States with different nitrification levels. The results reveal that combined chlorine is more effective for inactivating occluded microorganisms than free chlorine; model calibration results suggest that free chlorine is less effective because it is more reactive. However, nitrified effluents appear to have lower effluent particle concentrations, and decreases in particle concentrations significantly reduce the chlorine required. Additionally, in disinfection systems that are designed and operated based on inactivation of indicator organisms, the chlorine dose may be insufficient to inactivate occluded pathogens to levels consistent with current regulations.
Production of Biodiesel and Biogas from Algae: A Review of Process Train Options
Authors: Wiley Patrick E. , Campbell J. Elliott , McKuin Brandi
Published: April 2011

Algae are an attractive biofuel feedstock because of their fast growth rates and improved land use efficiency when compared with terrestrial crops. Process train components needed to produce algal biofuels include (1) cultivation, (2) harvesting, and (3) conversion into usable fuel. This paper compares various process train options and identifies knowledge gaps presently restricting the production of algal biodiesel and algae‐derived biogas. This analysis identified energy‐intensive processing and the inability to cultivate large quantities of lipid‐rich algal biomass as major obstacles inhibiting algal biodiesel production. Anaerobic digestion of algal biomass requires fewer process train components and occurs regardless of lipid content. In either scenario, the use of wastewater effluent as a cultivation medium seems necessary to reduce greenhouse gas emissions and maximize water use efficiency. Furthermore, anaerobically digesting algal biomass generated from low‐technology wastewater treatment processes represents an appropriate technology approach to algal biofuels that is poorly investigated. Coupling these processes can improve global health by improving sanitation, while providing a cleaner burning biogas alternative to indoor biomass cooking systems typical of less‐developed areas.
Effect of Pipe Sags on Wastewater Collection System Performance
Authors: Sever V. Firat , Foust Henry
Published: April 2011

Sagging of pipelines is a common problem in centralized wastewater collection systems. Wastewater flowing through sags experiences several changes of slope, and the flow through flat and negative slope sections is prone to a significant reduction in mean velocity. The objective of this study is to determine when pipe sags would result in significant velocities below design conditions, which also would increase the risk of a sewer backup. A sagged pipe configuration that could be encountered in sanitary sewer systems was depicted; thereby, analyses on uniform and gradually varied flows were conducted to determine velocity profiles through different segments of the sagged pipeline setup used for the study. The results indicate that there are significant occurrences when either the velocity in the pipe sags goes below minimum, as recommended in the Ten States Standards (Health Research, Inc., 2004) (0.61 m/s [2.0 ft/sec]), or flow depth rises to pipe diameter (full section flow). Additionally, velocities along a sagged pipe were calculated for temporal flow rates to account for daily and seasonal flow rate changes in a typical wastewater collection system. Results of the temporal flow rate analysis suggest that, for a 200‐mm (8‐in.) diameter sagged pipe segment with full‐section (wet weather) flow, 75% of the mean velocities would be below the minimum velocity recommended as a Ten States Standard.
Maxillary incisor root resorption induced by ectopic canines
Authors: Bjerklin Krister , Guitirokh Chanelle Houmet
Published: April 2011

Objective:

To evaluate the long-term clinical and radiographic effects of maxillary incisor root resorption in cases of ectopic canines treated during the late 1970s and 1980s in Jönköping, Sweden.

Subjects and Methods:

The material comprised 55 incisors in 38 subjects. The posttreatment follow-up time was 13 to 28 years. All subjects underwent intraoral radiography, 33 were referred for computed tomography or cone beam computed tomography, and 24 also underwent clinical examination. The severity of incisor root resorption was correlated with clinical characteristics. Radiographs of the resorptive lesions were documented in detail and compared with intraoral radiographs taken immediately posttreatment.

Results:

Four incisors in three subjects had been lost, in part because of root resorption. Of the 36 incisors with root resorption, the lesions were unchanged in 26 teeth, improved in three teeth, and exacerbated in seven. In one case the resorption had progressed to pulpal exposure, necessitating endodontic treatment. For most of the incisors, the periodontal ligament was more clearly defined and the lamina dura showed improved trabeculation. The clinical characteristics of the incisors with resorption were not significantly different from those of sound incisors.

Conclusions:

In this long-term follow-up, most cases of incisor root resorption induced by ectopic maxillary canines did not progress and teeth with root resorption showed no clinically relevant symptoms. The prognosis for long-term survival of teeth with resorbed roots is good, but in cases where extraction is indicated, lateral incisors with severe root resorption should be extracted in favor of healthy premolars.
The Causal Effect of Class Size on Academic Achievement
Authors: Shin Yongyun , Raudenbush Stephen W.
Published: April 2011

This article addresses three questions: Does reduced class size cause higher academic achievement in reading, mathematics, listening, and word recognition skills? If it does, how large are these effects? Does the magnitude of such effects vary significantly across schools? The authors analyze data from Tennessee’s Student/Teacher Achievement Ratio study (STAR) of 1985, where students and teachers are randomly assigned to a small or regular class. The authors propose a three-level multivariate simultaneous equation model with an instrumental variable (IV) and estimation via maximum likelihood (ML) to analyze the data under an assumption of data missing at random (MAR). The IV, random assignment of students to a small or regular class, reduces class size which, by hypothesis, improves academic achievement in these domains. The authors extend Rubin’s Causal Model (RCM) by involving a modified Stable Unit Treatment Value Assumption (SUTVA), requiring no interference between classrooms and intact schools. The method accommodates data with a general missing pattern and extracts full information for analysis from the STAR data. The authors investigate both homogenous and heterogenous causal effects of class size on academic achievement scores across schools. The results show that reducing class size improves reading, mathematics, listening, and word recognition test scores from kindergarten to third grade, although the effects appear relatively small in second grade. The authors find no evidence that the causal effects vary across schools.
Nanoparticles and modulation of immune responses
Authors: Pantic Igor
Published: April 2011

The exact role of engineered nanomaterials in immune system modulation remains unclear. The aim of this concise review is to give a comprehensive insight into recent published scientific data concerning the modulation of innate and adaptive immune responses by engineered nanoparticles, and to provide a basis for future experimental work related to designing safer, and more efficient biomaterials.
Electron Spin Resonance.: Part One: A Diagnostic Method in the Biomedical Sciences
Authors: Rhodes Christopher J.
Published: April 2011

A review is presented of some of the ways in which electron spin resonance (ESR) spectroscopy may be useful to investigate systems of relevance to the biomedical sciences. Specifically considered are: spin-trapping in biological media; the determination of antioxidant efficiencies; lipid-peroxidation; the use of nitroxides as probes of metabolic activity in cells and as structural probes of cell-membranes; ESR coupled with materials for radiation-dosimetry; food- and drug-irradiation; studies of enzyme systems and of cyclodextrins; diagnosis of cancer and rheumatoid arthritis; measurement of oxidative stress in synovial tissue in preparation for joint replacement; determination of oxidative species during kidney dialysis; measurement of biological oxygen concentrations (oximetry); trapping in living cells of the endothelium-derived relaxing factor nitric oxide (NO); measurement of hydrogen peroxide; determination of drugs of abuse (opiates); ESR measurements of whole blood and as a means to determine the age of bloodstains for forensic analysis are surveyed, and also a determination of the aqueous volume of human sperm cells is described, among other topics.
The Possibility of a Joint Communiqué: My Response to Hourdequin
Authors: Johnson Baylor
Published: April 2011

This article is a response to Marion Hourdequin, ‘Climate, Collective Action and Individual Ethical Obligations', Environmental Values 19 (2010): 443–464. As Hourdequin argues, we have an obligation to reduce our individual emissions of greenhouse gases. This obligation is not, however, to reduce to the level that would be sustainable if everyone else did likewise. We are obligated to make limited reductions in the service of our primary obligation to organise and embrace collective schemes to ensure that everyone reduces emissions and that benefits to the environment are proportionate to the sacrifices made. She and I can agree on the existence of an obligation if she recognises that there is a fundamental difference between the obligations we have to avoid individually harmful actions and our obligations in a tragedy of the commons.
Some Early Ethics of Geoengineering the Climate: A Commentary on the Values of the Royal Society Report
Authors: Gardiner Stephen M.
Published: April 2011

The Royal Society's landmark report on geoengineering is predicated on a particular account of the context and rationale for intentional manipulation of the climate system, and this ethical framework probably explains many of the Society's conclusions. Critical reflection on the report's values is useful for understanding disagreements within and about geoengineering policy, and also for identifying questions for early ethical analysis. Topics discussed include the moral hazard argument, governance, the ethical status of geoengineering under different rationales, the implications of understanding geoengineering as a consequence of wider moral failure, and ethical resistance to invasive interventions in environmental systems.
‘Nature and I are Two’: A Critical Examination of the Biophilia Hypothesis
Authors: Joye Yannick , De Block Andreas
Published: April 2011

In 1984, Edward O. Wilson proposed the idea that natural selection has resulted in an adaptive love of life-forms and life–like processes (‘biophilia') in humans. To date, the idea of biophilia has been viewed as an ultimate explanation of many conservation attitudes in humans. In this paper, we contend that environmental ethics has little to gain from the biophilia hypothesis. First, the notion is open to various and even conflicting interpretations. Second, the empirical findings that do seem to corroborate a more well–defined version of the biophilia hypothesis can often be accounted for by alternative hypotheses. Third, the evolutionary reasoning behind the biophilia hypothesis tends to be unclear, and sometimes even inaccurate.
What Lies Beneath the Surface? A Case Study of Citizens’ Moral Reasoning with Regard to Biodiversity
Authors: Ojala Maria , Lidskog Rolf
Published: April 2011

This paper focuses on a Swedish case where a biological insecticide has been used to fight mosquitoes in order to reduce the nuisance to humans. The case concerns conflicting values regarding environmental protection. People's quality of life in the summers is placed in opposition to long-term risks to biodiversity. On the surface, the affected lay-population is one-sidedly positive about the intervention. However, interviews with citizens revealed a more complex picture, where the majority also touched upon value conflicts. At the same time, different psychological mechanisms for handling these dilemmas hindered more critical and doubtful views from being included in societal deliberations concerning the intervention. By way of conclusion, we argue that it is important to create deliberative arrangements that acknowledge the emotional and contradictory side of human nature and that encourage people to dare to voice standpoints that may be seen as uncomfortable or inconsistent.
Mercy as an Environmental Virtue
Authors: Ferkany Matt
Published: April 2011

Recent work on environmental virtue tends to focus on the role of virtues like love, care, respect, humility and wonder for nature. This essay considers the merits of regarding mercy for nature as an environmental virtue. It argues that mercy for nature is neither conceptually confused nor unacceptably anthropo-centric, is exhibited by an important exemplar of environmental virtue, and is compatible with virtues of love, care, respect and humility. It also argues that efforts to inculcate environmental mercy may help facilitate the development of more caring, loving and respectful attitudes toward nature.
Writing the Wolf: Canine Tales and North American Environmental-Literary Tradition
Authors: Jones Karen
Published: April 2011

This article considers the construction of the wolf in North American environmental literature and history. Emphasis is placed on illustrating how writings about Canis lupus relate to shifting evaluations of wild nature and ethical responsibilities towards the non-human. It further reflects upon the limits to 'knowing' other species, as well as the struggle between amateurs and professionals in the quest to be seen as authorities in zoological expertise. An intensely symbolic animal, the wolf has always been a popular character in folklore, a creature representative of our fears and our idealisations of wilderness. Although the rehabilitation of the wolf in twentieth-century America is conventionally framed in terms of the rise of ecological science, of the wolf as a keystone predator and integral part of a healthy ecosystem, the naturalist tradition of storytelling remains another key element in this development. Under scrutiny here are those nature stories that have encouraged a positive attitude towards wolves in North America - from Ernest Thompson Seton in the late 1800s to Asta Bowen a century later. Such works suggest an important role for the storyteller as an educator in environmental values and contest the dominant paradigm of scientific observation as the 'saviour' of the wolf.
'At this point, the lichens in the trees are their only means of survival':A History of Tree Cutting for Winter Reindeer Fodder by Sami People in Northern Sweden
Authors: Berg Anna , Gunnarsson Bjorn , Ostlund Lars
Published: April 2011

The importance of land use history and its impact on ecological systems has recently been recognised, primarily because most 'natural areas' have been found to have experienced greater human interference than previously assumed. The extent of forest exploitation in pre-industrial times, especially by native people, has been consistently underestimated. In northern Sweden all the reindeer are herded by the native Sami people. During the winter, reindeer usually feed on ground lichens, which they dig for under the snow. Traditionally, trees with arboreal lichens were cut to provide supplementary food when adverse snow conditions prevented grazing. The stumps from such cuttings are commonly known as 'lichen-stumps' and they can be found in the few remaining unmanaged forest areas. In this study we examine the history, ecology and extent of this specific aspect of forest use by using an integrated approach involving both historical records and field studies. We found that the cutting of trees for lichens was a widespread practice during harsh winters, that significant numbers of trees were cut and that it ceased at the end of the nineteenth century, coinciding with large-scale changes in the land use of northern Scandinavia.
Violence Against People and the Land: The Environment and Refugee Migration from China's Henan Province, 1938-1945
Authors: Muscolino Micah S.
Published: April 2011

This article examines interrelationships between environmental change and refugee displacement in North China's Henan province during the Sino-Japanese War of 1937-1945. Henan had a larger displaced population than any part of China during World War II, with most refugees migrating due to war-induced disasters that were the second-order effects of warfare. The Chinese Nationalist military's blasting of the Yellow River dikes to block a Japanese military advance in June 1938 displaced millions, forcing them to seek livelihoods in areas away from their home villages. In 1942-1943 Yellow River flooding combined with inclement weather conditions and heavy military grain exactions to create a famine of massive proportions in Henan, leading millions more residents to flee. The most severe ecological damage took place in areas of Henan that flood and famine refugees left, as labour shortages led to neglect and decline of human-constructed environments. Hydraulic infrastructure collapsed, agricultural cultivation came to a standstill and previously settled areas became desolate wastelands. Environmental degradation occurred on a more limited scale in areas of in-migration, as refugees heightened pressure on resources. In Shaanxi province, China's wartime state resettled refugees and mobilised them to reclaim land, leading to deforestation and accelerated soil erosion. The article engages with previous literature on the environmental consequences of refugee migration, questioning the notion that refugees have an unmediated impact on the environment. It is argued that refugee migration is impossible to isolate from other factors that lead to ecological damage in wartime settings.
Intercontinental Transport of Dust: Science and Policy, pre-1800s to 1967
Authors: Wilkening Ken
Published: April 2011

I begin with this paper a history of science and policy related to intercontinental transport of air pollution, starting with long-range atmospheric transport of dust from the pre-1800s to 1967. Dust is spotlighted because it was the first trace substance ('pollutant') recognised to travel intercontinental and global distances and because long-range transport in some locations of the world was eventually seen to be associated with large-scale environmental problems. Based on data gathered from primary and secondary written source materials, I conclude that, relative to sustainability, the outstanding achievement between 1800 and 1967 was development of an Earth-spanning conceptual structure that fused scientific knowledge, environmental ethics and options for political action, what I call a dust-related 'Earth system problem-framework'. Specifically, scientists outlined a world dust-system framework with a land ethic at its core. The arduous path to this accomplishment highlights the large-scale, long-term, multidisciplinary effort required to create holistic, whole-Earth conceptual structures for global environment governance.
Canine Mammary Cancer Stem Cells are Radio- and Chemo- Resistant and Exhibit an Epithelial-Mesenchymal Transition Phenotype
Authors: Pang Lisa Y. , Cervantes-Arias Alejandro , Else Rod W. , Argyle David J.
Published: April 2011

Canine mammary carcinoma is the most common cancer among female dogs and is often fatal due to the development of distant metastases. In humans, solid tumors are made up of heterogeneous cell populations, which perform different roles in the tumor economy. A small subset of tumor cells can hold or acquire stem cell characteristics, enabling them to drive tumor growth, recurrence and metastasis. In veterinary medicine, the molecular drivers of canine mammary carcinoma are as yet undefined. Here we report that putative cancer stem cells (CSCs) can be isolated form a canine mammary carcinoma cell line, REM134. We show that these cells have an increased ability to form tumorspheres, a characteristic of stem cells, and that they express embryonic stem cell markers associated with pluripotency. Moreover, canine CSCs are relatively resistant to the cytotoxic effects of common chemotherapeutic drugs and ionizing radiation, indicating that failure of clinical therapy to eradicate canine mammary cancer may be due to the survival of CSCs. The epithelial to mesenchymal transition (EMT) has been associated with cancer invasion, metastasis, and the acquisition of stem cell characteristics. Our results show that canine CSCs predominantly express mesenchymal markers and are more invasive than parental cells, indicating that these cells have a mesenchymal phenotype. Furthermore, we show that canine mammary cancer cells can be induced to undergo EMT by TGFβ and that these cells have an increased ability to form tumorspheres. Our findings indicate that EMT induction can enrich for cells with CSC properties, and provide further insight into canine CSC biology.
Contrast-Enhanced Ultrasound (CEUS) for Echographic Detection of Hepato Cellular Carcinoma in Cirrhotic Patients Previously Treated with Multiple Techniques: Comparison of Conventional US, Spiral CT and 3-Dimensional CEUS with Navigator Technique (3DNav CEUS)
Authors: Giangregorio Francesco
Published: April 2011

A commercially available technique named “NAVIGATOR” (Esaote, Italy) easily enables a 3-D reconstruction of a single 2-D acquisition of Contrast Enhanced Ultrasound (CEUS) imaging of the whole liver (with a volumetric correction thanks to the electromagnetic device of NAVIGATOR). Aim of the study was to evaluate this “panoramic” technique in comparison with conventional US and spiral CT in the detection of new hepatic lesions. 144 cirrhotic patients (previously treated for hepato cellular carcinoma (HCC)) in follow-up with detection of 98 new nodules (N), 28 multinodular (Nmulti), 14 loco-regional regrowth (LR) 94 efficaciously treated without new nodules (neg) and four multinodular without new nodules, were submitted to 200 examinations with this new technique from November 2008 to November 2009. 3DNavCEUS was performed using SonoVue (Bracco), as contrast agent, and a machine (Technos MPX, Esaote). Spiral CT and 3DNav CEUS were performed in the same month during follow up. Sens.,Spec.,diagn.-Acc.,PPV and NPV were evaluated; comparison and differences between the techniques were obtained with chi-square (SPSS release-15). Final diagnosis was: 98 new lesions (N) (one to three), 28 multinodular HCC (Nmulti) and 14 loco-regional regrowth (LR); in 94 no more lesions were observed during follow-up; conventional US obtained: 58 N (+18 multinodularN and 8 LR), 40 false negative (+10 Nmulti and 6 LR) (sens:59.2, spec:100%, Diagn Accur:73.6, PPV:100; NPV:70.1); spiral CT obtained: 84N (+26-multinodularN and 14-LR), 14 false-negative (+2-Nmulti), and one false-positive (sens:85.7, spec:97.9%, Diagn Accur:90.9, PPV:97.7; NPV:86.8); 3DNAV obtained: 92N (+28 multinodularN and 14LR), 6 false-negative, and two false-positives (sens:93.9, spec:97.9%, Diagn Accur:95.6, PPV:97.9; NPV:93.9). 3-DNav CEUS is significantly better than US and almost similar to spiral CT for detection of new HCC. This technique, in particular, showed the presence of lesions even in the cases not detected with spiral CT.
Brain Cancer Stem Cells: Current Status on Glioblastoma Multiforme
Authors: Facchino Sabrina , Abdouh Mohamed , Bernier Gilbert
Published: April 2011

Glioblastoma multiforme (GBM), an aggressive brain tumor of astrocytic/neural stem cell origin, represents one of the most incurable cancers. GBM tumors are highly heterogeneous. However, most tumors contain a subpopulation of cells that display neural stem cell characteristics in vitro and that can generate a new brain tumor upon transplantation in mice. Hence, previously identified molecular pathways regulating neural stem cell biology were found to represent the cornerstone of GBM stem cell self-renewal mechanism. GBM tumors are also notorious for their resistance to radiation therapy. Notably, GBM “cancer stem cells” were also found to be responsible for this radioresistance. Herein, we will analyze the data supporting or not the cancer stem cell model in GBM, overview the current knowledge regarding GBM stem cell self-renewal and radioresistance molecular mechanisms, and discuss the potential therapeutic application of these findings.
Apoptosis and DNA Methylation
Authors: Meng Huan X. , Hackett James A. , Nestor Colm , Dunican Donncha S. , Madej Monika , Reddington James P. , Pennings Sari , Harrison David J. , Meehan Richard R.
Published: April 2011

Epigenetic mechanisms assist in maintaining gene expression patterns and cellular properties in developing and adult tissues. The molecular pathology of disease states frequently includes perturbation of DNA and histone methylation patterns, which can activate apoptotic pathways associated with maintenance of genome integrity. This perspective focuses on the pathways linking DNA methyltransferases and methyl-CpG binding proteins to apoptosis, and includes new bioinformatic analyses to characterize the evolutionary origin of two G/T mismatch-specific thymine DNA glycosylases, MBD4 and TDG.
Targeted Alpha Therapy Approach to the Management of Pancreatic Cancer
Authors: Allen Barry J. , Rizvi Syed M. Abbas , Qu Chang F. , Smith Ross C.
Published: April 2011

Evidence for the efficacy of targeted alpha therapy for the control of pancreatic cancer in preclinical models is reviewed. Results are given for in vitro pancreatic cancer cells and clusters and micro-metastatic cancer lesions in vivo. Two complementary targeting vectors are examined. These are the C595 monoclonal antibody that targets the MUC1 antigen and the PAI2 ligand that targets the uPA receptor. The expression of the tumor-associated antigen MUC-1 and the uPA receptor on three pancreatic cancer cell lines is reported for cell clusters, human mouse xenografts and lymph node metastases, as well as for human pancreatic cancer tissues, using immuno-histochemistry, confocal microscopy and flow cytometry. The targeting vectors C595 and PAI2 were labeled with the alpha emitting radioisotope 213Bi using the chelators cDTPA and CHX-A″ to form the alpha-conjugates (AC). Cell clusters were incubated with the AC and examined at 48 hours. Apoptosis was documented using the TUNEL assay. In vivo, the anti-proliferative effect for tumors was tested at two days post-subcutaneous cell inoculation. Mice were injected with different concentrations of AC by local or systemic administration. Changes in tumor progression were assessed by tumor size. MUC-1 and uPA are strongly expressed on CFPAC-1, PANC-1 and moderate expression was found CAPAN-1 cell clusters and tumor xenografts. The ACs can target pancreatic cells and regress cell clusters (~100 µm diameter), causing apoptosis in some 70–90 % of cells. At two days post-cell inoculation in mice, a single local injection of 74 MBq/kg of AC causes complete inhibition of tumor growth. Systemic injections of 111, 222 and 333 MBq/kg of alpha-conjugate caused significant tumor growth delay in a dose dependent manner after 16 weeks, compared with the non-specific control at 333 MBq/kg. Cytotoxicity was assessed by the MTS and TUNEL assays. The C595 and PAI2-alpha conjugates are indicated for the treatment of micro-metastatic pancreatic cancer with over-expression of MUC1 and uPA receptors in post-surgical patients with minimal residual disease. The observation of tumor regression in a Phase I clinical trial of targeted alpha therapy for metastatic melanoma indicates that alpha therapy can regress tumors by a process called tumor anti-vascular alpha therapy (TAVAT). As a consequence, this therapy could be indicated for the management of non-surgical pancreatic cancer tumors.
Emerging Diseases in European Forest Ecosystems and Responses in Society
Authors: Stenlid Jan , Oliva Jonàs , Boberg Johanna B. , Hopkins Anna J.M.
Published: April 2011

New diseases in forest ecosystems have been reported at an increasing rate over the last century. Some reasons for this include the increased disturbance by humans to forest ecosystems, changed climatic conditions and intensified international trade. Although many of the contributing factors to the changed disease scenarios are anthropogenic, there has been a reluctance to control them by legislation, other forms of government authority or through public involvement. Some of the primary obstacles relate to problems in communicating biological understanding of concepts to the political sphere of society. Relevant response to new disease scenarios is very often associated with a proper understanding of intraspecific variation in the challenging pathogen. Other factors could be technical, based on a lack of understanding of possible countermeasures. There are also philosophical reasons, such as the view that forests are part of the natural ecosystems and should not be managed for natural disturbances such as disease outbreaks. Finally, some of the reasons are economic or political, such as a belief in free trade or reluctance to acknowledge supranational intervention control. Our possibilities to act in response to new disease threats are critically dependent on the timing of efforts. A common recognition of the nature of the problem and adapting vocabulary that describe relevant biological entities would help to facilitate timely and adequate responses in society to emerging diseases in forests.
Preparing for and Responding to Disturbance: Examples from the Forest Sector in Sweden and Canada
Authors: Keskitalo E. Carina H. , Klenk Nicole , Bullock Ryan , Smith Andrea L. , Bazely Dawn R.
Published: April 2011

Coping or adaptation following large-scale disturbance may depend on the political system and its preparedness and policy development in relation to risks. Adaptive or foresight planning is necessary in order to account and plan for potential risks that may increase or take place concurrently with climate change. Forests constitute relevant examples of large-scale renewable resource systems that have been directly affected by recent environmental and social changes, and where different levels of management may influence each other. This article views disturbances in the forest sectors of Sweden and Canada, two large forest nations with comparable forestry experiences, in order to elucidate the preparedness and existing responses to multiple potential stresses. The article concludes that the two countries are exposed to stresses that indicate the importance of the governing and institutional system particularly with regard to multi-level systems including federal and EU levels. While economic change largely results in privatization of risk onto individual companies and their economic resources (in Canada coupled with a contestation of institutional systems and equity in these), storm and pest outbreaks in particular challenge institutional capacities at administrative levels, within the context provided by governance and tenure systems.
A Service Oriented Architecture for Personalized Universal Media Access
Authors: Tönnies Sascha , Köhncke Benjamin , Hennig Patrick , Brunkhorst Ingo , Balke Wolf-Tilo
Published: April 2011

Multimedia streaming means delivering continuous data to a plethora of client devices. Besides the actual data transport, this also needs a high degree of content adaptation respecting the end users’ needs given by content preferences, transcoding constraints, and device capabilities. Such adaptations can be performed in many ways, usually on the media server. However, when it comes to content editing, like mixing in subtitles or picture-in-picture composition, relying on third party service providers may be necessary. For economic reasons this should be done in a service-oriented way, because a lot of adaptation modules can be reused within different adaptation workflows. Although service-oriented architectures have become widely accepted in the Web community, the multimedia environment is still dominated by monolithic systems. The main reason is the insufficient support for working with continuous data: generally the suitability of Web services for handling complex data types and state-full applications is still limited. In this paper we discuss extensions of Web service frameworks, and present a first implementation of a service-oriented framework for media streaming and digital item adaptation. The focus lies on the technical realization of the services. Our experimental results show the practicality of the actual deployment of service-oriented multimedia frameworks.
An Optimal Centralized Carbon Dioxide Repository for Florida, USA
Authors: Poiencot Brandon , Brown Christopher
Published: April 2011

For over a decade, the United States Department of Energy, and engineers, geologists, and scientists from all over the world have investigated the potential for reducing atmospheric carbon emissions through carbon sequestration. Numerous reports exist analyzing the potential for sequestering carbon dioxide at various sites around the globe, but none have identified the potential for a statewide system in Florida, USA. In 2005, 83% of Florida’s electrical energy was produced by natural gas, coal, or oil (e.g., fossil fuels), from power plants spread across the state. In addition, only limited research has been completed on evaluating optimal pipeline transportation networks to centralized carbon dioxide repositories. This paper describes the feasibility and preliminary locations for an optimal centralized Florida-wide carbon sequestration repository. Linear programming optimization modeling is used to plan and route an idealized pipeline network to existing Florida power plants. Further analysis of the subsurface geology in these general locations will provide insight into the suitability of the subsurface conditions and the available capacity for carbon sequestration at selected possible repository sites. The identification of the most favorable site(s) is also presented.
Intensity and Inhalation of Smoking in the Aetiology of Laryngeal Cancer
Authors: Ramroth Heribert , Dietz Andreas , Becher Heiko
Published: April 2011

The carcinogenic effect of smoking on laryngeal cancer is well established; however, the risk pattern for detailed smoking characteristics is less clear. Thus, the aim of this analysis was to quantify the impact of different inhalation behaviours on the risk of laryngeal cancer. We conducted a population-based case control study in Germany, frequency-matched for sex and age, using a standardized questionnaire covering lifelong smoking details, including age at start, time since quitting, types of smoking products, duration, intensity and inhalation behaviour. We found higher risks for increasing duration and intensity of smoking. A clear dose-response relationship was found in all inhalation subgroups, i.e., not only for deep inhalers, but also for those puffing on a cigarette. Clearly reduced risks could be observed for quitting smoking. Changing inhalation habits might be considered as a first step to reducing the risk of developing laryngeal cancer. However, the best way to effectively reduce laryngeal cancer risk is to quit smoking.