bluuebunny/crossref_metadata_2025 huggingface dataset:
Trefoil factor 3 promotes metastatic seeding and predicts poor survival outcome of patients with mammary carcinoma
Authors: Pandey Vijay , Wu Zheng-Sheng , Zhang Min , Li Rui , Zhang Jian , Zhu Tao , Lobie Peter E
Published: September 2014

Introduction

Recurrence or early metastasis remains the predominant cause of mortality in patients with estrogen receptor positive (ER+) mammary carcinoma (MC). However, the molecular mechanisms underlying the initial progression of ER+ MC to metastasis remains poorly understood. Trefoil factor 3 (TFF3) is an estrogen-responsive oncogene in MC. Herein, we provide evidence for a functional role of TFF3 in metastatic progression of ER+ MC.

Methods

The association of TFF3 expression with clinicopathological parameters and survival outcome in a cohort of MC patients was assessed by immunohistochemistry. The expression of TFF3 in MCF7 and T47D cells was modulated by forced expression or siRNA-mediated depletion of TFF3. mRNA and protein levels were determined using qPCR and western blot. The functional effect of modulation of TFF3 expression in MC cells was determined in vitro and in vivo. Mechanistic analyses were performed using reporter constructs, modulation of signal transducer and activator of transcription 3 (STAT3) expression, and pharmacological inhibitors against c-SRC and STAT3 activity.

Results

TFF3 protein expression was positively associated with larger tumour size, lymph node metastasis, higher stage, and poor survival outcome. Forced expression of TFF3 in ER+ MC cells stimulated colony scattering, cell adhesion to a Collagen I-coated matrix, colony formation on a Collagen I- or Matrigel-coated matrix, endothelial cell adhesion, and transmigration through an endothelial cell barrier. In vivo, forced expression of TFF3 in MCF7 cells stimulated the formation of metastatic nodules in animal lungs. TFF3 regulation of the mRNA levels of epithelial, mesenchymal, and metastatic-related genes in ER+ MC cells were consistent with the altered cell behaviour. Forced expression of TFF3 in ER+ MC cells stimulated phosphorylation of c-SRC that subsequently increased STAT3 activity, which lead to the downregulation of E-cadherin. siRNA-mediated depletion of TFF3 reduced the invasiveness of ER+ MC cells.

Conclusions

TFF3 expression predicts metastasis and poor survival outcome of patients with MC and functionally stimulates cellular invasion and metastasis of ER+ MC cells. Adjuvant functional inhibition of TFF3 may therefore be considered to ameliorate outcome of ER+ MC patients.
Fish consumption and risk of rheumatoid arthritis: a dose-response meta-analysis
Authors: Di Giuseppe Daniela , Crippa Alessio , Orsini Nicola , Wolk Alicja
Published: September 2014

Introduction

The association between fish consumption and rheumatoid arthritis (RA) is unclear. The aim of this paper was to summarize the available evidence on the association between fish consumption and risk of RA using a dose-response meta-analysis.

Methods

Relevant studies were identified by a search of MEDLINE and EMBASE through December 2013, with no restrictions. A random-effects dose-response meta-analysis was conducted to combine study specific relative risks. Potential non-linear relation was investigated using restricted cubic splines. A stratified analysis was conducted by study design.

Results

Seven studies (four case-controls and three prospective cohorts) involving a total of 174 701 participants and 3346 cases were included in the meta-analysis. For each one serving per week increment in fish consumption, the relative risk (RR) of RA was 0.96 (95% confidence interval (CI) 0.91 to 1.01). Results did not change when stratifying by study design. No heterogeneity or publication bias was observed. When fish consumption was modeled using restricted cubic splines, the risk of RA was 20 to 24% lower for 1 up to 3 servings per week of fish (RR =0.76, 95% CI: 0.57 to 1.02) as compared to never consumption.

Conclusions

Results from this dose-response meta-analysis showed a non-statistically significant inverse association between fish consumption and RA.
Targeted exon sequencing fails to identify rare coding variants with large effect in rheumatoid arthritis
Authors: Bang So-Young , Na Young-Ji , Kim Kwangwoo , Joo Young Bin , Park Youngho , Lee Jaemoon , Lee Sun-Young , Ansari Adnan A , Jung Junghee , Rhee Hwanseok , Lee Jong-Young , Han Bok-Ghee , Ahn Sung-Min , Won Sungho , Lee Hye-Soon , Bae Sang-Cheol
Published: September 2014

Introduction

Although it has been suggested that rare coding variants could explain the substantial missing heritability, very few sequencing studies have been performed in rheumatoid arthritis (RA). We aimed to identify novel functional variants with rare to low frequency using targeted exon sequencing of RA in Korea.

Methods

We analyzed targeted exon sequencing data of 398 genes selected from a multifaceted approach in Korean RA patients (n = 1,217) and controls (n = 717). We conducted a single-marker association test and a gene-based analysis of rare variants. For meta-analysis or enrichment tests, we also used ethnically matched independent samples of Korean genome-wide association studies (GWAS) (n = 4,799) or immunochip data (n = 4,722).

Results

After stringent quality control, we analyzed 10,588 variants of 398 genes from 1,934 Korean RA case controls. We identified 13 nonsynonymous variants with nominal association in single-variant association tests. In a meta-analysis, we did not find any novel variant with genome-wide significance for RA risk. Using a gene-based approach, we identified 17 genes with nominal burden signals. Among them, VSTM1 showed the greatest association with RA (P = 7.80 × 10-4). In the enrichment test using Korean GWAS, although the significant signal appeared to be driven by total genic variants, we found no evidence for enriched association of coding variants only with RA.

Conclusions

We were unable to identify rare coding variants with large effect to explain the missing heritability for RA in the current targeted resequencing study. Our study raises skepticism about exon sequencing of targeted genes for complex diseases like RA.
The risk of cancer in patients with rheumatoid arthritis taking tumor necrosis factor antagonists: a nationwide cohort study
Authors: Wu Chun-Ying , Chen Der-Yuan , Shen Jui-Lung , Ho Hsiu J , Chen Chih-Chiang , Kuo Ken N , Liu Han-Nan , Chang Yun-Ting , Chen Yi-Ju
Published: September 2014

Introduction

The association between cancer and use of biologic therapy among rheumatoid arthritis (RA) patients remains controversial. We aimed to compare the relative risk of cancer development between RA patients taking tumor necrosis factor α (TNFα) antagonists and those taking nonbiologic disease-modifying anti-rheumatic drugs (nbDMARDs).

Methods

We conducted a nationwide cohort study between 1997 and 2011 using the Taiwan National Health Insurance Research Database. The risk of newly diagnosed cancer was compared between patients starting TNF-α antagonists (biologics cohort) and matched subjects taking nbDMARDs only (nbDMARDs cohort). Cumulative incidences and hazard ratios (HR) were calculated after adjusting for competing mortality. Standardized incidence ratio (SIR) was calculated for cancer risk. Multivariate analyses were performed using Cox proportional hazards model.

Results

We compared 4426 new users of TNF-α antagonists and 17704 users of nbDMARDs with similar baseline covariate characteristics. The incidence rates of cancer among biologics and nbDMARDs cohorts were 5.35 (95% confidence interval (CI) 4.23 to 6.46) and 7.41 (95% CI 6.75 to 8.07) per 1000 person-years, respectively. On modified Cox proportional hazards analysis, the risk of cancer was significantly reduced in subjects in biologics cohort (adjusted HR 0.63, 95% CI 0.49 to 0.80, P < .001), after adjusting for age, gender, disease duration, major co-morbidities, and prior use of DMARDs and corticosteroids. However, there was an increased risk for hematologic cancers in biologics cohort, yet without statistical significance. The effect of biologics was consistent across all multivariate stratified analyses and the association between biologics use and cancer risk was independent of dosage of concomitant nbDMARDs.

Conclusion

These findings suggested that RA patients taking TNF-α antagonist are associated with a lower risk of cancer, but not for hematologic cancers, than RA patients taking nbDMARDs alone.
Biodegradation of variable-chain-length n-alkanes in Rhodococcus opacus R7 and the involvement of an alkane hydroxylase system in the metabolism
Authors: Zampolli Jessica , Collina Elena , Lasagni Marina , Di Gennaro Patrizia
Published: September 2014

Rhodococcus opacus R7 is a Gram-positive bacterium isolated from a polycyclic aromatic hydrocarbon contaminated soil for its versatile metabolism; indeed the strain is able to grow on naphthalene, o-xylene, and several long- and medium-chain n-alkanes. In this work we determined the degradation of n-alkanes in Rhodococcus opacus R7 in presence of n- dodecane (C12), n- hexadecane (C16), n- eicosane (C20), n- tetracosane (C24) and the metabolic pathway in presence of C12. The consumption rate of C12 was 88%, of C16 was 69%, of C20 was 51% and of C24 it was 78%. The decrement of the degradation rate seems to be correlated to the length of the aliphatic chain of these hydrocarbons. On the basis of the metabolic intermediates determined by the R7 growth on C12, our data indicated that R. opacus R7 metabolizes medium-chain n-alkanes by the primary alcohol formation. This represents a difference in comparison with other Rhodococcus strains, in which a mixture of the two alcohols was observed. By GC-MSD analysis we also identified the monocarboxylic acid, confirming the terminal oxidation.

Moreover, the alkB gene cluster from R. opacus R7 was isolated and its involvement in the n-alkane degradation system was investigated by the cloning of this genomic region into a shuttle-vector E. coli-Rhodococcus to evaluate the alkane hydroxylase activity. Our results showed an increased biodegradation of C12 in the recombinant strain R. erythropolis AP (pTipQT1-alk R7) in comparison with the wild type strain R. erythropolis AP. These data supported the involvement of the alkB gene cluster in the n-alkane degradation in the R7 strain.
Small-Molecule “BRCA1-Mimetics” Are Antagonists of Estrogen Receptor-α
Authors: Ma Yongxian , Tomita York , Preet Anju , Clarke Robert , Englund Erikah , Grindrod Scott , Nathan Shyam , De Oliveira Eliseu , Brown Milton L. , Rosen Eliot M.
Published: September 2014

Context:

Resistance to conventional antiestrogens is a major cause of treatment failure and, ultimately, death in breast cancer.

Objective:

The objective of the study was to identify small-molecule estrogen receptor (ER)-α antagonists that work differently from tamoxifen and other selective estrogen receptor modulators.

Design:

Based on in silico screening of a pharmacophore database using a computed model of the BRCA1-ER-α complex (with ER-α liganded to 17β-estradiol), we identified a candidate group of small-molecule compounds predicted to bind to a BRCA1-binding interface separate from the ligand-binding pocket and the coactivator binding site of ER-α. Among 40 candidate compounds, six inhibited estradiol-stimulated ER-α activity by at least 50% in breast carcinoma cells, with IC50 values ranging between 3 and 50 μM. These ER-α inhibitory compounds were further studied by molecular and cell biological techniques.

Results:

The compounds strongly inhibited ER-α activity at concentrations that yielded little or no nonspecific toxicity, but they produced only a modest inhibition of progesterone receptor activity. Importantly, the compounds blocked proliferation and inhibited ER-α activity about equally well in antiestrogen-sensitive and antiestrogen-resistant breast cancer cells. Representative compounds disrupted the interaction of BRCA1 and ER-α in the cultured cells and blocked the interaction of ER-α with the estrogen response element. However, the compounds had no effect on the total cellular ER-α levels.

Conclusions:

These findings suggest that we have identified a new class of ER-α antagonists that work differently from conventional antiestrogens (eg, tamoxifen and fulvestrant).
Synthesis of Thienothiadiazole–Benzothiadiazole Alternating Copolymers and Their Application to Bulk Heterojunction Solar Cells
Authors: Umeyama Tomokazu , Watanabe Yusuke , Miyata Tetsushi , Imahori Hiroshi
Published: September 2014

Novel conjugated polymers incorporating thieno[3,4-c][1,2,5]thiadiazole (TTD) and 2,1,3-benzothiadiazole (BT) were synthesized. The TTD–BT copolymers displayed broad absorption bands in visible–near-infrared regions with optical band gaps of 1.1–1.2 eV. The HOMO energy levels were lower than those of TTD–oligothiophene alternating copolymers due to the electron-deficient nature of the BT unit. The photovoltaic device consisting of the polymer and a fullerene derivative ([70]PCBM) showed power conversion efficiencies of 0.01–0.08% under simulated AM 1.5G irradiation of 100 mW cm−2.
Estrogen as Jekyll and Hyde: regulation of cell death
Authors: Zhou Wen , Zhu Xiaoxia
Published: September 2014

Sustained estrogenic exposure increases the risk and/or the progression of various cancers, including those of the breast, endometrium and ovary. Unexpectedly, physiological level of estrogen together with a novel IKKα inhibitor BAY11-7082 could effectively induce cell apoptosis in ER-positive breast cancer cells, suggesting combining estrogen with IKKα inhibition may be beneficial for breast cancer patients. This opinion article touches upon the dual role estrogen played in inducing cancer cell death and asks whether use of estrogen in combination with IKKα-targeted therapy would be possible reconsider the newly identified crosstalk between ER and NFκB pathway which can be utilized to switch the effects of estrogen on cell death.
[18F]-T807 tauopathy PET imaging in chronic traumatic encephalopathy
Authors: Gandy Sam , DeKosky Steven T.
Published: September 2014

A new molecular ligand for positron emission tomography (PET) of the human brain, [18F]-T807, is under investigation for the antemortem detection of pathological neurofibrillary aggregates, which are evidence of neurofibrillary tangle (NFT) diseases, also known as tauopathies. Repetitive mild traumatic brain injuries in athletes and battlefield veterans are associated with one such tauopathy, known as chronic traumatic encephalopathy (CTE). In a recent case report, a former NFL player with clinically probable CTE and a concurrent Progressive Supranuclear Palsy (PSP) –like syndrome was studied using [18F]-T807. The interpretation of this player’s [18F]-T807 PET imaging was complicated by the overlap of tracer uptake in brain regions involved in CTE and PSP with regions associated with either nonspecific [18F]-T807 ligand binding or “aging-associated” binding of [18F]-T807 to authentic tauopathy known to be associated with aging and disease severity (i.e., NFT in the mesial temporal lobe). The implications of these data for the utility of [18F]-T807 in the pre-mortem detection of CTE are summarized.
Neonatal skin cleansing revisited: Whether or not to use skin cleansing products
Authors: Hugill Kevin
Published: September 2014

Beyond the need to effectively remove urine and faeces from the nappy area and ensure that skin folds and creases do not become a potential focus of infection, the hygiene needs of most neonates are fairly minimal. Despite this limited need intense debate about skin cleansing and whether or not to use skincare products has endured. Currently the use of skincare products and preparations with neonates is widely proscribed. However, recent research is now challenging one of the central dogmas of neonatal skin care; that water alone is best. This article revisits advice about the use of skin cleansing products in term healthy newborns in the light of new research and suggests there is a need for a more considered and nuanced articulation of the advice provided to parents on this important aspect of care.
Comparison of instrumental vaginal births by assisted birth practitioner midwives and medical practitioners
Authors: Davison Margaret Anne , Murray Sarah , Whitaker Lucy , Rendall Lesley , Gammie Nicky , Magowan Brian
Published: September 2014

The role of the assisted birth practitioner (ABP) midwife is extending the traditional scope of midwifery practice to include instrumental vaginal births.

A retrospective cohort study was carried out to examine the 6 months immediately after the introduction of ABP midwives into the middle-grade tier of a medical practitioner rota. Maternal and neonatal outcomes of births by ABP midwives were compared to those by medical practitioner. The results were analysed with a combination of independent (P<0.05), Mann-Whitney U and chi-square tests as appropriate. Qualitative data were also collected.

Of 57 instrumental vaginal births, 14 were performed by ABP midwives (25%) and 43 by medical practitioners (75%). Baseline demographic characteristics between the two groups were similar. There were no significant differences in maternal outcomes or in neonatal outcomes. Qualitative data were also very positive.

These results provide reassurance to both service users and providers. ABP midwives are able to offer a valuable and safe extended role through instrumental births.
Investigation of collapse in small animals
Authors: Patteson Mark
Published: September 2014

This article reviews the ways to distinguish syncope from other forms of collapse, discusses the potential causes of syncope and describes appropriate diagnostic techniques. While the different diseases that can cause syncope are well documented, data on relative prevalence and frequency of syncope in different conditions are sparse, reflecting the difficulty that often exists in reaching a precise diagnosis in many cases.
The emotional links behind the increase in cosmetic dentistry
Authors: Horridge Gayna
Published: September 2014

With the ever-increasing pressure from the media and peers to look good and feel good, the rate of cosmetic dentistry in the UK is greatly increasing
Future Development of the Norwegian Forest Industry, Based on Industry Expectations
Authors: Sjølie Hanne K. , Bysheim Kristian , Nyrud Anders Q. , Flæte Per Otto , Solberg Birger
Published: September 2014

Forest industries worldwide are facing a range of challenges, such as declining demand for newsprint, fluctuating sawn-wood prices, and society's concern of forestry's negative environmental impacts. On the other hand, the growing interest in bioenergy and renewable products may represent opportunities for the forest sector. Few assessments of the industry's expectations regarding future development of the major external forces driving the forest sector seem to have been carried out. We undertook two participatory surveys of sawn-wood industry managers in Norway in 2010 and 2013, assessing their expectations of how key factors develop until 2020. The respondents expressed beliefs that the demand for sawn-wood and bioenergy will grow and that sawmilling productivity will increase together with international trade. Society's concern for the environment was expected to rise, leading to higher demand for wood products but also more expensive forestry operations. A bioenergy demand increase of 50 percent, very high energy prices, competitive second-generation biofuel, and the first second-generation biofuel plant being established in Norway were perceived to be notably less likely in 2013 than in 2010. The questions were associated with scenarios of the Norwegian forest sector used in quantitative scenario analyses. In the 2013 survey, less support was given to the scenario with high priority on environmental issues and rapid bioenergy deployment. Recent policy and market shifts that imply a lower emphasis on the environment and cheaper fossil fuels may help explain this change. The survey indicates that short-term shifts in policy and economic factors may considerably impact key agents' assumptions about the future.
Potential for Using Essential Oils to Protect Viscoelastic Thermal Compression–Treated Hybrid Poplar
Authors: Scouse Adam , Kamke Frederick A. , Morrell Jeffrey J.
Published: September 2014

The potential for using pretreatment with cinnamon leaf oil or juniper foliage oil to improve the durability of viscoelastic thermal compression (VTC)–treated hybrid poplar was explored in a field termite test and a laboratory mold test. The addition of oils prior to VTC processing had variable effects on resistance to both mold and termite attack. Subsequent gas chromatography–mass spectroscopy assessment of residual oil components in VTC processed material suggested that the heating associated with the process was associated with substantial degradation of oil components that might help explain the lack of protective effect. The results suggest that further attempts to use essential oils to improve the durability of VTC processed materials must first explore less aggressive heating conditions to reduce the potential for thermal degradation of oil components while still achieving the attractive gains in physical properties associated with the process.
Dwelling as an approach to creative pedagogy
Authors: Hughes Dean
Published: September 2014

This research article looks to provide an alternate account of creative pedagogy to the predominant view that maintaining change and the generation of options is the bastion of creative teaching. A tenet of modern art is that it eschews continuity of form in favour of ideological disjuncture. The zenith of this paralogical development being the dematerialization of the art object and the conceptual turn in art making. From 1968 onwards, free from material certainties, and aiming itself beyond the commodity address of historic modernism, contemporary art has proved to be an uncomfortable relative of education. Artistic practice has developed a problematic relationship to knowledge. A contested and unshackled pursuit, it possesses no consistent method and its teaching is cloaked in the overtly mythological outline of tacit-knowledge. The resurgence in popularity of Donald Barthelme’s 1987 essay Not-Knowing is symptomatic of the hiatus that is now at the centre of the expansion of artistic pedagogy. This article sees the known and accepted view of the development of art pedagogy subjugating a parallel account of creative development that has stasis, dwelling and the maintaining of a fixed position at its core. This research suggests that an alternate account of artistic creativity can be developed from a number of artists who emerged during early and late 1960s whose artistic contribution was to establish a fixed and defined position that has remained unchanged for over 40 years. This article will look at the artistic work of two British Artists who have long-standing relationships to British and European Art education (Alan Charlton, Roger Ackling) to present a counterpoint to ‘not knowing’.
The problem with making in fine art: A case for the expanded teaching of drawing
Authors: Chorpening Kelly
Published: September 2014

Written and verbal skills have risen in prominence within today’s fine art curriculum. Their provision is clearly outlined and quantified, and this is beginning to overshadow what happens ‘in the studio’. This article outlines ‘the problem with making’ in fine art education today by focusing on the teaching of drawing, asking the questions: what exactly are the skills of drawing, what is gained by learning them, and how, in practice, are they intertwined with theory? By establishing the educational value of drawing, we might then influence ways skills in general are perceived and deployed within fine art education today.
Contamination of endemic plants of Amazonia by ubiquitary pollution: Persistent organic pollutants (POPs) determination by GC-MS/MS
Authors: Falcinelli Stefano , Giorgini Martino , Sebastiani Bartolomeo
Published: September 2014

We report on the results of an analytical investigation about the contamination on three officinal plants of Amazonian rain forest due to Persistent Organic Pollutants (POPs), like organochlorine pesticides and polychlorinated biphenyls (PCBs). The analyzed plants "balsamina" (Impatiens Balsamina), "mullaca" (Physalis Angulata) and "graviola" (Annona Muricata) come from the Amazonian forest of the Peru where they grow spontaneously. All the three plants are well known for their numerous therapeutic properties and commonly they are used in the traditional medicine against several diseases like cancer, fever, diabetes, etc. A portion of about l0 g for each vegetable sample was submitted to extraction procedure with hexaneacetone (1:1, v/v) solution by using soxhlet technique for 24h, following procedures by ISTISAN 99/28. The three extracts were analyzed by Gas ChromatographyTandem Mass Spectrometry (GCMS/MS) and Multi Reaction Monitoring (MRM) techniques (by using ion trap detector Varian Saturn 2200 system) after their purification by chromatography on celite column eluted with nhexane (ISTISAN 99/25). The obtained results show the presence of DDT and its metabolites, like DDD e DDE in the three analyzed samples and of hexachlorobenzene only in the "graviola" (0.041 g/kg). The total POPs quantities are in the concentration range of ppb, varying from 0.349 and 0.614 g/kg respectively for "mullaca" and "graviola", up to 2.328 g/kg in the case of "balsamina". These concentration values are an indication of a plants contamination in trace due to the organochlorinated pesticides coming from an ubiqitary pollution and not from a direct use of these substances in the place of origin of the samples. Finally, concerning the PCBs determination, the analysis GCMS/MS excludes their presence in all the three plants investigated: the concentration values are in this case lower than the detection limit of the method (0.0030.013 g/kg).
Kv1.3 inhibitors: en route to clinical trials
Authors: Tasler Stefan , Dreker Tobias , Krimmelbein Ilga , Hamm Svetlana
Published: September 2014

The voltage-gated potassium channel Kv1.3 represents a promising target for the treatment of autoimmune diseases like multiple sclerosis, rheumatoid arthritis, uveitis and psoriasis as it is a crucial player in maintaining the activation signal within T-cells, allowing for a selective suppression of autoimmunity and thus minimizing the potential for opportunistic infections during therapy. The Lead Optimization Program for two small molecule hit classes resulted in a fine-tuning of activity, selectivity and physicochemical and PK properties. Selected representatives display highly encouraging ameliorative effects within a set of animal models relevant in the context of autoimmune diseases, comparable or even favourable over positive controls like methotrexate, betamethasone or tacrolimus. Such inhibitors showed excellent tolerability in rats upon oral treatment with high doses for up to a month, had no effect on haematology and clinical biochemistry parameters and did not affect cells of the innate immunity or naive T-cells, clearly emphasizing their unique selling point, which is a highly specific immunosuppression of autoreactive T-cells.
Taming Super Lewis Acids for Catalysis: The Family of Ferrocene-Stabilized Silicon Cations
Authors: Oestreich Martin , Klare Hendrik , Müther Kristine , Fröhlich Roland
Published: September 2014

Tricoordinate silicon cations are exceptionally strong electron pair acceptors, so strong that they react with almost any and basic molecule. In order to use such reactive intermediates in synthetic chemistry, Lewis acid catalysis in particular, we have designed intramolecularly stabilized silylium ions whose electron deficiency is attenuated by an adjacent, electron-rich ferrocenyl fragment. Here we wish to present the synthesis and structural characterization of these unique transition metal-stabilized silicon cations which reveal an unprecedented bonding situation different from its isoelectronic analogues. The potential of this motif is further highlighted in challenging DielsAlder reactions, which are catalyzed at low temperatures with exceptional reaction rates and selectivities.
Bis(Silylene) Pincer Type Ligands: A Silicon System to Explore in the Universe of Catalysis
Authors: Gallego Daniel
Published: September 2014

Silylenes have shown coordination strength within the range of the well-studied phosphanes and carbene ligands, however, their transition metal (TM) complexes are rare in the catalytic arena. On the other hand, pincer ligands are wide spread in catalysis due to the versatile features in their chemical structure (i.e. electron density, steric effects, rigidity, solubility, etc.). Herein, we report the synthesis of novel bis-silylene monoanionic SiCHSi and neutral SiNSi pincer ligands, and their late TMs complexes. These systems act as catalysts in the borylation of arenes, Sonogashira coupling, and hydrosilation of ketones. Remarkably, these ligands exhibit higher -donor strength than phosphanes and a reaction intermediate from a C-C coupling reaction was also isolated and is reported.
Environmental policy and economic growth: the macroeconomic implications of the health effect
Authors: Chen Jhy-hwa , Shieh Jhy-yuan , Chang Juin-jen
Published: September 2014

This paper introduces health effects in an endogenous growth model with environmental concerns. To highlight the importance of health effects, we examine the time allocation of households in regard to leisure, labor, and health care, which play a crucial role in affecting the impacts of public abatement and emission taxation. We not only show that the health effect modifies the conventional consequences of environmental policy, but also thoroughly compare the effectiveness of these two distinct environmental policies. We also conduct transition and welfare analyses in a dynamic optimizing model which offers novel policy implications, given that the literature on health effects is silent on these issues.
Investigation on a Soft Tubular Model Reactor Based on Bionics of Small Intestine – Residence Time Distribution
Authors: Deng Renpan , Pang Liqing , Xu Yufen , Li Lin , Wu Xuee , Chen Xiao Dong
Published: September 2014

The human small intestine is responsible for virtually all nutrient uptake and more than 95% of the water absorption in digestion, which is attributed to the vast mucosal surface area and the peristalsis of small intestine. Under the broad conceptual framework of bio-inspired chemical process engineering, by mimicking the structure and functions of small intestine, a flexible tubular reactor with villous protrusions distributed evenly on the inner wall was designed and constructed in this study. In order to understand the flow behavior in the reactor, the residence time distribution (RTD) of fluid particles in the reactor was measured by introducing electrochemical active tracer. Also, a simple mechanism of peristalsis was introduced, and its effects on the RTD in the reactor were investigated. The experimental results showed that the tailing of RTD function curve in the small intestine model reactor was extended significantly compared to a normal tubular reactors. The residence time and mixing of fluid (particles) in the reactor can be regulated efficiently by controlling the peristaltic actions (frequency and location).
External actors’ role in solving local collective action problems in a post-conflict setting: A case study of Turkish Cypriot beekeepers
Authors: Gokcekus Omer , Finnegan Clare , Cakal Huseyin
Published: September 2014

In addition to legal constraints and social-psychological barriers, in a post-conflict setting mutually beneficial economic transactions might not occur due to the widening gap between the health, quality, and environmental standards of the parties. A lack of incentives during the years of conflict prevent the members of the weaker party, the one economically isolated from the rest of the world, from engaging in the collective learning necessary to upgrade the health and packaging standards of their commodities. In this study, we detail the technical, political, and legal challenges external actors must consider in order to successfully help small businesses in a post-conflict environment. Specifically, we explain how the EU helped Turkish Cypriot beekeepers by supplying funds to support training and educational programs, and upgrade the equipment used by the beekeepers. We demonstrate that third parties, like the EU, can provide the impetus for domestic institutions—such as producers associations, chambers of commerce, and cooperatives—to overcome their collective action problem. [JEL codes: D74, H56, O1]
Hearts and minds cannot be bought: Ineffective reconstruction in Afghanistan
Authors: Child Travers Barclay
Published: September 2014

Recent work has suggested the foreign-led reconstruction effort carried out in Afghanistan and Iraq can mitigate violence because it helps win the “hearts and minds” of local people. For the case of Afghanistan, we show there is no evidence behind such an assertion. Analyzing unique data on Commander’s Emergency Response Program (CERP) spending across the country from 2005 to 2009, we find no discernible effect of the reconstruction effort on violence. In light of the absence of empirical evidence for the success of the CERP, we suggest the hearts and minds credo currently guiding U.S. policy be reconsidered. [D74, H56, O1]
Bayesian networks for habitat suitability modeling: a potential tool for conservation planning with scarce resources
Authors: Tantipisanuh Naruemon , Gale George A. , Pollino Carmel
Published: September 2014

Bayesian networks (BN) have been increasingly used for habitat suitability modeling of threatened species due to their potential to construct robust models with limited survey data. However, previous applications of this approach have only occurred in countries where human and budget resources are highly available, but the highest concentrations of threatened vertebrates globally are located in the tropics where resources are much more limited. We assessed the effectiveness of Bayesian networks in generating habitat suitability models in Thailand, a biodiversity‐rich country where the knowledge base is typically sparse for a wide range of threatened species. The Bayesian network approach was used to generate habitat suitability maps for 52 threatened vertebrate species in Thailand, using a range of evidence types, from relatively well‐documented species with good local knowledge to poorly documented species, with few local experts. Published information and expert knowledge were used to define habitat requirements. Focal species were categorized into 22 groups based on known habitat preferences, and then habitat suitability models were constructed with outcomes represented spatially. Models had a consistent structure with three major components: potential habitat, known range, and threat level. Model classification sensitivity was tested using presence‐only field data for 21 species. Habitat models for 12 species were relatively sensitive (>70% congruency between observed and predicted locations), three were moderately congruent, and six were poor. Classification sensitivity tended to be high for bird models and moderate for mammals, whereas sensitivity for reptiles was low, presumably reflecting the relatively poor knowledge base for reptiles in the region. Bayesian network models show significant potential for biodiversity‐rich regions with scarce resources, although they require further refinement and testing. It is possible that one detailed ecological study is sufficient to develop a model with reasonable sensitivity, but BN models for species groups with no quantitative data continue to be problematic.
How do animals optimize the size–number trade‐off when aging? Insights from reproductive senescence patterns in marmots
Authors: Berger Vérane , Lemaître Jean-François , Gaillard Jean-Michel , Cohas Aurélie
Published: September 2014

We investigated the influence of female age on five reproductive traits and on the offspring size–number trade‐off from an extensive data set spanning 20 years of study on free‐ranging Alpine marmots. Offspring mass increased with female age, whereas litter size and reproductive allocation remained constant in females up to 10 years of age and declined thereafter. Although reproductive allocation declined, post‐weaning juvenile survival and the size–number trade‐off did not change markedly throughout a female's lifetime. Senescence of annual reproductive success (i.e., the number of offspring surviving their first hibernation within a given litter) only resulted from senescence of litter size. The data were insufficient to determine whether the decrease in litter size with age was caused by declining litter size at birth, offspring pre‐weaning survival, or both. Regardless, our findings demonstrate that marmot females display a size–number trade‐off invariant with age, and that their reproductive tactic involves increasing offspring size at the cost of decreasing litter size with increasing age. As a result, reproductive performance remains constant throughout a female's lifetime, despite the deleterious effects of senescence in litter size.
Spartina alterniflora with high tolerance to salt stress changes vegetation pattern by outcompeting native species
Authors: Tang Long , Gao Yang , Li Bo , Wang Qing , Wang Cheng-Huan , Zhao Bin
Published: September 2014

Although many studies have been conducted on the interspecific competition between new arrivals and native plants, few of them have demonstrated how these processes interact with non‐resource factors to determine vegetation pattern. This study investigated how salt stress mediates competition between native Phragmites australis and invasive Spartina alterniflora and thus changes plant communities in Dongtan, a Chinese coast salt marsh. The experiments revealed that the growth and reproduction of the native species declined with increasing salinity but that the invasive species performed well in the salinity range of 0–20‰, illustrating why the invader could proliferate in the high salinity mudflats in Dongtan. Moreover, the native had a high growth rate and therefore exhibited a competitive dominance over the invader at low salinity of ca. 7‰. Thus, the invader could not displace the native, and the native communities were stable in the low salinity zones. In contrast, the growth rate of the invader became higher when salinity increased; correspondingly, it gained the competitive dominance at high salinity of ca. 11‰. As a result, the invader colonising the native communities in high salinity zones performed better and could displace the natives over time. Consequently, after invasive S. alterniflora colonisation, the vegetation pattern of Dongtan marsh gradually changed from “mudflat–sedge–P. australis” to “mudflat–S. alterniflora” and “mudflat–S. alterniflora and natives” along the elevation gradients. The findings of the case study demonstrated that if a new arrival has a wide tolerance range to major non‐resource stress in an ecosystem, it can not only displace natives by interspecific competition in high stress zones but can also spread into the zones without natives; on the other hand, natives with a narrow ecological amplitude in relation to the non‐resource stress can only persist in low stress zones. Therefore, the distribution area of new arrivals increases as the distribution area of natives decreases. Because some non‐resource stresses have substantial positive effects on native community invasibility, the practices that change the level of non‐resource stress and create favorable conditions for invasive species should be stopped.
Community restructuring can maintain diversity across a severity gradient in the absence of foundation species
Authors: Harris Liam W. , Elliott Tammy L. , Davies T. Jonathan
Published: September 2014

Phylogenetic community structure can provide insight into the ecological dynamics that drive species co‐occurrence and community assembly patterns. Understanding these patterns is important for predicting future community composition in the context of climate change and other anthropogenic disturbances. However, we know little about how these environmental stressors might change interspecific interactions. Here we present an analysis on the role of putative foundation species (cushion‐type life forms) in determining the phylogenetic community composition of vascular plants at the local scale. We also investigated how community diversity and structure shifts across an environmental severity gradient. Abundance data for vascular plants was collected within and outside of four focal cushion plant species along an elevation gradient in Canadian alpine tundra. We compared differences in species‐specific abundance within plots with foundation plants to the same measure in adjacent open plots. Using a time‐calibrated molecular phylogeny, we quantified community structure metrics, including the net relatedness index (NRI), a novel net relatedness to focal index (NRFI), and an index of species co‐occurrence across the gradient. We examined the trends in these indices with cushion plant presence/absence and environmental severity using both linear regression and mixed effect models. We found that the loss of species richness at higher elevations was counterbalanced by a decrease in interspecific relatedness, maintaining phylogenetic diversity across the gradient. We found no evidence for community diversity or structure modifications by cushion plants, nor any evidence that species were preferentially associating with these hypothesized foundation species. On the contrary, many species had significantly negative co‐occurrence with the cushion plants. Overall, our results suggest that the cushion plant life forms may exhibit interspecific dynamics that are at least as competitive as they are facilitative. The decrease in phylogenetic clustering with elevation suggests that traits that allow persistence in these conditions are convergent at the local scale.
A study of the kinetics and isotherms for Cr(VI) adsorption in a binary mixture of Cr(VI)–Ni(II) using hierarchical porous carbon obtained from pig bone
Authors: Li Chengxian , Huang Zhe , Huang Bicheng , Liu Changfeng , Li Chengming , Huang Yaqin
Published: September 2014

Cr(VI) adsorption in a binary mixture Cr(VI)–Ni(II) using the hierarchical porous carbon prepared from pig bone (HPC) was investigated. The various factors affecting adsorption of Cr(VI) ions from aqueous solutions such as initial concentration, pH, temperature and contact time were analyzed. The results showed excellent efficiency of Cr(VI) adsorption by HPC. The kinetics and isotherms for Cr(VI) adsorption from a binary mixture Cr(VI)-Ni(II) by HPC were studied. The adsorption equilibrium described by the Langmuir isotherm model is better than that described by the Freundlich isotherm model for the binary mixture in this study. The maximum adsorption capacity was reliably found to be as high as 192.68 mg/g in the binary mixture at pH 2. On fitting the experimental data to both pseudo-first- and second-order equations, the regression analysis of the second-order equation gave a better R2 value.
Combined seawater toilet flushing and urine separation for economic phosphorus recovery and nitrogen removal: a laboratory-scale trial
Authors: Mackey H. R. , Zheng Y.-S. , Tang W.-T. , Dai J. , Chen G.-H.
Published: September 2014

Freshwater toilet flushing consumes 20–35% of typical household water demand. Seawater toilet flushing, as practised by Hong Kong since 1958, provides an alternative water source. To maximise the benefits of this unique dual water supply, urine separation could be combined to allow low-cost struvite production and subsequent urine nitrification – in-sewer denitrification. This paper reports on a laboratory-scale study of seawater urine phosphate recovery (SUPR) and seawater–urine nitrification. A laboratory-scale SUPR reactor was run under three phases with hydraulic retention time between 1.5 and 6 h, achieving 91–96% phosphorus recovery. A urine nitrification sequencing batch reactor (UNSBR) was also run for a period of over 650 days, averaging 90% ammonia removal and loading of up to 750 mg-N/L.d. Careful control of the SUPR phosphate removal was found necessary for operation of the downstream UNSBR, and system integration considerations are discussed.
Influence of wave and current flow on sediment-carrying capacity and sediment flux at the water–sediment interface
Authors: Zheng Jun , Li Ruijie , Yu Yonghai , Suo Anning
Published: September 2014

In nearshore waters, spatial and temporal scales of waves, tidal currents, and circulation patterns vary greatly. It is, therefore, difficult to combine these factors’ effects when trying to predict sediment transport processes. This paper proposes the concept of significant wave velocity, which combines the effects of waves, tides, and ocean currents using the horizontal kinetic energy superposition principle. Through a comparison of the relationship between shear stress at the water–sediment interface and sediment-carrying capacity, assuming equilibrium sediment flux, a new formula for sediment-carrying capacity, which incorporates the concept of significant wave velocities, is derived. Sediment-carrying capacity is a function of the critical velocity, which increases with water depth and decreases with increasing relative roughness of the seabed. Finally, data from field observation stations and simulations are used to test the proposed formula. The results show that the new formula is in good agreement with both field and simulation data. This new formula for sediment-carrying capacity can be used to simulate nearshore sediment transport.
Characterization of naphthalene degradation by Streptomyces sp. QWE-5 isolated from active sludge
Authors: Xu Peng , Ma Wencheng , Han Hongjun , Hou Baolin , Jia Shengyong
Published: September 2014

A bacterial strain, QWE-5, which utilized naphthalene as its sole carbon and energy source, was isolated and identified as Streptomyces sp. It was a Gram-positive, spore-forming bacterium with a flagellum, with whole, smooth, convex and wet colonies. The optimal temperature and pH for QWE-5 were 35 °C and 7.0, respectively. The QWE-5 strain was capable of completely degrading naphthalene at a concentration as high as 100 mg/L. At initial naphthalene concentrations of 10, 20, 50, 80 and 100 mg/L, complete degradation was achieved within 32, 56, 96, 120 and 144 h, respectively. Kinetics of naphthalene degradation was described using the Andrews equation. The kinetic parameters were as follows: qmax (maximum specific degradation rate) = 1.56 h−1, Ks (half-rate constant) = 60.34 mg/L, and KI (substrate-inhibition constant) = 81.76 mg/L. Metabolic intermediates were identified by gas chromatography and mass spectrometry, allowing a new degradation pathway for naphthalene to be proposed. In this pathway, monooxygenation of naphthalene yielded naphthalen-1-ol. Further degradation by Streptomyces sp. QWE-5 produced acetophenone, followed by adipic acid, which was produced as a combination of decarboxylation and hydroxylation processes.