bluuebunny/crossref_metadata_2025 huggingface dataset:
Pro‐opiomelanocortin gene delivery suppresses the growth of established Lewis lung carcinoma through a melanocortin‐1 receptor‐independent pathway
Authors: Tsai Han‐En , Liu Li‐Feng , Dusting Gregory J. , Weng Wen‐Tsan , Chen San‐Cher , Kung Mei‐Lan , Tee Richard , Liu Guei‐Sheung , Tai Ming‐Hong
Published: December 2011

Background

Pro‐opiomelanocortin (POMC) is the precursor of several neuropeptides, such as corticotropin, melanocyte‐stimulating hormone and the endogenous opioid (β‐endorphin). Our previous studies have indicated that POMC gene delivery inhibited the progression and metastasis of B16‐F10 melanoma via the α‐ melanocyte‐stimulating hormone/melanortin‐1 receptor (MC‐1R) pathway.

Methods

In the present study, the therapeutic efficacy of POMC gene therapy was evaluated in mice bearing established Lewis lung carcinoma (LLC) models both in vitro and in vivo. We also investigated the MC‐1R‐independent mechanism underlying POMC gene therapy.

Results

We found that POMC gene delivery significantly inhibited the growth and colony formation in MC‐1R‐deficient LLC cells. In addition, POMC gene transfer effectively suppressed the growth of established LLC in mice. The inhibitory mechanisms underlying POMC gene delivery were attibuted to be inhibition of proliferation and the induction of apoptosis. Moreover, POMC gene delivery attenuated tumor β‐catenin signaling by reducing protein levels of β‐catenin and its downstream proto‐oncogenes, including cyclin D1 and c‐myc. Lastly, POMC gene delivery induced a significant suppression of tumor vasculature.

Conclusions

These results support the existence of an MC‐1R‐independent pathway for POMC gene therapy, which further expands the therapeutic spectrum of POMC therapy for multiple types of cancer. Copyright © 2012 John Wiley & Sons, Ltd.
A unified approach to known and unknown cases of Berge's conjecture
Authors: Berger Eli , Hartman Irith Ben‐Arroyo
Published: December 2011

Berge's elegant dipath partition conjecture from 1982 states that in a dipath partition P of the vertex set of a digraph minimizing , there exists a collection Ck of k disjoint independent sets, where each dipath P∈P meets exactly min{|P|, k} of the independent sets in C. This conjecture extends Linial's conjecture, the Greene–Kleitman Theorem and Dilworth's Theorem for all digraphs. The conjecture is known to be true for acyclic digraphs. For general digraphs, it is known for k=1 by the Gallai–Milgram Theorem, for k⩾λ (where λis the number of vertices in the longest dipath in the graph), by the Gallai–Roy Theorem, and when the optimal path partition P contains only dipaths P with |P|⩾k. Recently, it was proved (Eur J Combin (2007)) for k=2.

There was no proof that covers all the known cases of Berge's conjecture. In this article, we give an algorithmic proof of a stronger version of the conjecture for acyclic digraphs, using network flows, which covers all the known cases, except the case k=2, and the new, unknown case, of k=λ−1 for all digraphs. So far, there has been no proof that unified all these cases. This proof gives hope for finding a proof for all k.
An investigation on reference crop evapotranspiration trend from 1975 to 2005 in Iran
Authors: Kousari Mohammad Reza , Ahani Hossein
Published: December 2011

Evapotranspiration is one of the most important factors in agriculture and the hydrological cycle that can be influenced by global warming and climatic changes. In this study, the trend of reference crop evapotranspiration (ET0) computed by penman Penman‐Monteith equation and surveyed in 42 synoptic weather stations during last 3 decades (1975–2005). Nonparametric statistical test, Kendall's rank correlation (or τ test) was used to determine ET0 trends. Although, downward and upward trends were observed, increasing trends had more frequency. Spatial analysis of results indicated upward trends especially in the boundary parts of the country while, no significant trends were distributed in central parts. In addition, correlation analysis between ET0 trend and other climatic parameters trend (the trend of mean temperature, mean of minimum temperature, and mean of maximum temperature, mean of relative humidity, mean of wind speed and mean of sunshine duration) showed that wind is the most effective parameter on ET0. Iran losses more than 70% of annual precipitation by ET0. It is obvious that in this country where there are many limitations for water resources management, increase in ET0 could lead to more problems. Copyright © 2011 Royal Meteorological Society
Prion proteins (PRNP and PRND) are over‐expressed in osteosarcoma
Authors: Sollazzo Vincenzo , Galasso Marco , Volinia Stefano , Carinci Francesco
Published: December 2011

Although osteosarcoma is the most common bone malignancy, the molecular and cellular mechanisms influencing its pathogenesis have remained elusive. Prion proteins (PRNP and PRND), known mostly for its involvement in neurodegenerative spongiform encephalopathies, have been recently demonstrated to be involved in resistance to apoptosis, tumorigenesis, proliferation, and metastasis. The main aim of research was to study whether prion proteins were over‐expressed in human osteosarcoma, and if prion proteins could have a role also in osteosarcomas. We evaluated differential gene expression between 22 cases of osteosarcoma and 40 cases of normal bone specimens through cDNA microarray analysis spanning a substantial fraction of the human genome. PRNP and PRND are significantly over‐expressed in osteosarcoma. PRNP and PRND appear involved with some important genes related to tumorigenesis and apoptosis. PRNP is linked to PTK2, RBBP9, and TGFB1 while PRND is linked to TNFSF10, BCL2A1, NFKB2, and TP53RK. Increased expression on Affymetrix arrays of prion proteins seems to be associated with the development of osteosarcoma. Prions seem to induce a negative regulation of apoptosis, thus promoting osteosarcoma development and progression. Osteosarcoma is a very aggressive tumor and even after modern chemotherapy and excision of tumors efforts are needed to improve clinical outcome. Since Prion proteins seem to be related to osteosarcoma development, their inhibition could represent a new approach to the molecular treatment of osteosarcoma. © 2011 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1004–1012, 2012
Treatment of complex PTSD: Results of the ISTSS expert clinician survey on best practices
Authors: Cloitre Marylene , Courtois Christine A. , Charuvastra Anthony , Carapezza Richard , Stolbach Bradley C. , Green Bonnie L.
Published: December 2011

This study provides a summary of the results of an expert opinion survey initiated by the International Society for Traumatic Stress Studies Complex Trauma Task Force regarding best practices for the treatment of complex posttraumatic stress disorder (PTSD). Ratings from a mail‐in survey from 25 complex PTSD experts and 25 classic PTSD experts regarding the most appropriate treatment approaches and interventions for complex PTSD were examined for areas of consensus and disagreement. Experts agreed on several aspects of treatment, with 84% endorsing a phase‐based or sequenced therapy as the most appropriate treatment approach with interventions tailored to specific symptom sets. First‐line interventions matched to specific symptoms included emotion regulation strategies, narration of trauma memory, cognitive restructuring, anxiety and stress management, and interpersonal skills. Meditation and mindfulness interventions were frequently identified as an effective second‐line approach for emotional, attentional, and behavioral (e.g., aggression) disturbances. Agreement was not obtained on either the expected course of improvement or on duration of treatment. The survey results provide a strong rationale for conducting research focusing on the relative merits of traditional trauma‐focused therapies and sequenced multicomponent approaches applied to different patient populations with a range of symptom profiles. Sustained symptom monitoring during the course of treatment and during extended follow‐up would advance knowledge about both the speed and durability of treatment effects.
Vicarious exposure to trauma and growth in therapists: The moderating effects of sense of coherence, organizational support, and empathy
Authors: Brockhouse Rebecca , Msetfi Rachel M. , Cohen Keren , Joseph Stephen
Published: December 2011

Therapists who work with traumatized individuals can experience psychological growth following this vicarious exposure to trauma. The purpose of the present study is to examine the variables that may moderate such vicarious posttraumatic growth. Therapists (N = 118) completed measures of vicarious exposure to trauma and growth, as well as empathy, sense of coherence, and perceived organizational support. Results showed that having a strong sense of coherence negatively predicted growth (β = −.28, p = .001), whereas empathy was a positive predictor (β = .37, p < .001). Empathy also moderated the exposure to growth relationship when growth involved relating to others (β = −.20; p = .018). Organizational support did not predict growth. The results have implications for the recruitment, training, and supervision of therapists working with individuals who have experienced trauma.
Environmental persistence of Brucella abortus in the Greater Yellowstone Area
Authors: Aune Keith , Rhyan Jack C. , Russell Robin , Roffe Thomas J. , Corso Barbara
Published: December 2011

Bison (Bison bison) and elk (Cervus elaphus) of the Greater Yellowstone Area (GYA) are the last remaining reservoirs of bovine brucellosis (Brucella abortus) in the United States. An important factor in evaluating the risk of transmission to cattle is the persistence of bacteria and infectious birth materials shed on pastures where cattle graze. We selected 2 study areas near the northern and western boundaries of Yellowstone National Park (YNP) to determine the persistence of bacteria on fetal tissue, soil, and vegetation, and scavenging on infectious materials from birth and abortion sites. We performed 3 independent field experiments to determine: 1) persistence of Brucella abortus (RB51) purposely applied to fetal tissues, 2) scavenging of fetuses by native scavengers, and 3) natural contamination of birth or abortion sites in the GYA. Results from these field experiments established that Brucella bacteria can persist on fetal tissues and soil or vegetation for 21–81 days depending on month, temperature, and exposure to sunlight. Bacteria purposely applied to fetal tissues persisted longer in February than May and did not survive on tissues beyond 10 June regardless of when they were set out. Brucella abortus field strain persisted up to 43 days on soil and vegetation at naturally contaminated bison birth or abortion sites. Fetuses were scavenged by a variety of birds and mammals in areas near YNP and more rapidly inside YNP than outside the Park boundary. Models derived from our data determined a 0.05% chance of bacterial survival beyond 26 days (95% Credible Interval of 18–30 days) for a contamination event in May. May 15 is the final date for hazing all bison into Yellowstone National Park under the current interagency bison management plan. With these data managers can predict when it is safe to graze cattle onto pastures previously occupied by bison. © 2011 The Wildlife Society.
Evaluating spatially explicit viability of a declining ruffed grouse population
Authors: Blomberg Erik J. , Tefft Brian C. , Reed J. Michael , McWilliams Scott R.
Published: December 2011

Species associated with early successional habitats have experienced dramatic declines in the eastern United States as a result of land use changes and human disruption of natural disturbance regimes. Consequently, active management is required to create early successional habitat and promote plant and animal communities that depend on periodic forest disturbance. Ruffed grouse (Bonasa umbellus) depend on recently disturbed forest habitat, and have experienced dramatic declines over the last half‐century. Although ruffed grouse are extensively studied, little effort has been made to link population dynamics with habitat management at landscape scales. We used stochastic, spatially explicit population models that combined landscape conditions derived from a Geographic Information System with demographic data, and applied the model to a declining ruffed grouse population in Rhode Island, USA. We identified vital rates that influence ruffed grouse population dynamics using baseline models constructed with current demographic rates and landscape conditions, and assessed the effect of landscape‐scale forest management alternatives on population persistence by running multiple management simulations. Baseline models typically predicted population decline, and we concluded that vital rates (survival and recruitment) had a greater influence on population persistence than did dispersal capability, carrying capacity, or initial population size. Management simulations predicted greater population persistence under a scenario where high‐quality habitat was provided in fewer large blocks as opposed to many small blocks, and the rate at which we allowed ruffed grouse to colonize newly created habitat had a substantial impact on management success. Populations of ruffed grouse in the eastern United States are likely to continue to decline given current disturbance regimes, and our work provides a link between ruffed grouse demography and landscape‐scale habitat conditions to support management decisions. © 2011 The Wildlife Society.
A cross‐sectional study of the change in mastoid geometry with age in children without a history of otitis media
Authors: Swarts J. Douglas , Foley Sean , Alper Cuneyt M. , Doyle William J.
Published: December 2011

Objectives/Hypothesis:

This study assessed the normal growth and development of mastoid air‐cell system (MACS) geometry from infancy through adolescence.

Study Design:

Cross‐sectional study.

Methods:

This cross‐sectional study evaluated the change with age in MACS volume, surface area, and surface area/volume ratio in 36 (72 ears) individuals aged 1.6 to 18 years with no history of middle ear disease. The three MACS parameters were reconstructed using computed tomography (CT) scans judged by a radiologist to be normal. Linear regression was used to determine the relationship between the left and right values of each parameter, and between those parameters and age for male and female subjects.

Results:

For all three MACS parameters, the right and left values were highly correlated. MACS volume and surface area for male and female subjects showed an increase between 1 and 18 years. The surface area/volume ratio for males was independent of age but showed a shallow increase for females. When averaged across all ages, the ratio was similar to those previously reported.

Conclusions:

The growth trajectory for MACS volume observed in this study was not consistent with other cross‐sectional studies employing planimetry or CT of normal subjects that reported inconsistent results. Because of its potential role as a susceptibility factor for otitis media and other otologic problems, it is important to describe the growth and development of MACS geometry. Additional well‐controlled studies of this phenomenon are needed to clarify which of the growth trajectories actually describe the growth process for the three parameters of interest.
LONG‐TERM MANURING AND FERTILIZER EFFECTS ON DEPLETION OF SOIL ORGANIC CARBON STOCKS UNDER PEARL MILLET‐CLUSTER BEAN‐CASTOR ROTATION IN WESTERN INDIA
Authors: Srinivasarao CH. , Venkateswarlu B. , Lal R. , Singh A. K. , Kundu S. , Vittal K. P. R. , Patel J. J. , Patel M. M.
Published: December 2011

Soil organic carbon (SOC) pools are important for maintaining soil productivity and reducing the net CO2 loading of the atmosphere. An 18‐year old long‐term field experiment involving pearl millet‐cluster bean‐castor sequence was conducted on an Entisol in western India to examine the effects of chemical fertilizers and manuring on carbon pools in relation to crop productivity and C sequestration. The data showed that even the addition of 33.5 Mg ha−1 C inputs through crop residues as well as farm yard manure could not compensate the SOC depletion by oxidation and resulted in the net loss of 4.4 Mg C ha−1 in 18 years. The loss of SOC stock in the control was 12 Mg C ha−1. Conjunctive use of chemical fertilizers along with farm yard manure produced higher agronomic yields and reduced the rate of SOC depletion. The higher average seed yields of pearl millet (809 kg ha−1), cluster bean (576), and castor (827) over six cropping seasons were obtained through integrated use of fertilizers and manure. For every Mg increase in profile SOC stock, there was an overall increase of 0.46 Mg of crop yield, comprising increase in individual yield of pearl millet (0.17 Mg ha−1 y−1 Mg−1 SOC), cluster bean (0.14) and castor (0.15). The magnitude of SOC build up was proportional to the C inputs. Carbon pools were significantly correlated with SOC, which increased with application of organic amendments. Threshold C input of 3.3 Mg C ha−1 y−1 was needed to maintain the SOC stock even at the low antecedent level. Copyright © 2011 John Wiley & Sons, Ltd.
Natively Unfolded State for Engineering Nanoscale Fibrillar Arrays
Authors: Ryadnov Maxim G. , Cherny Dmitry I.
Published: December 2011

A generic rationale for the fabrication of high aspect ratio fibrillar nanoscale arrays is described. The design emulates an intermittence effect observed for β‐structured α‐synunclein fibrils, reported herein, in a structurally unrelated α‐helical fiber. The generated nanoarrays are composed of periodic nanosized segments separated at uniform distances of unfolded regions. These regions can be targeted for conformational binding and refolding with metal nanoparticle–peptide conjugates for the conversion of fibrillar arrays into nanoparticle arrays. The introduced concept opens new strategies for engineering novel nanoscale materials and devices.

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Surviving mission drift: How charities can turn dependence on government contract funding to their own advantage
Authors: Bennett Roger , Savani Sharmila
Published: December 2011

The widespread contracting out to British charities of welfare services previously furnished by the state has resulted in many charities operating in fields well outside those specified by their original missions. Challenges connected with charity mission drift have received a great deal of (mainly negative and critical) attention in the nonprofit practitioner literature in recent years, yet no academic research has been completed into exactly how charities respond managerially and operationally to government‐induced mission drift. This empirical study attempted to fill this important gap in knowledge about charity management through in‐depth case studies of three charities known to have experienced substantial mission drift during the last decade, focusing on the styles and types of approach the organizations had adopted in their dealings with government funding agencies. It emerged that the three charities accepted mission drift as a fact of life. Rather than simply supplying contract services to government bodies, the charities were highly proactive in seeking to initiate, direct, control, and assume overall strategic responsibility for state‐funded activities.
Identification of educational and infrastructural barriers to prompt antibiotic delivery in febrile neutropenia: A quality improvement initiative
Authors: Burry Erica , Punnett Angela , Mehta Ashley , Thull‐Freedman Jennifer , Robinson Lisa , Gupta Sumit
Published: December 2011

Background

Antibiotic administration within 60 minutes of presentation for medical care may be used as a treatment target for febrile neutropenia (FN); however, anecdotal evidence suggests this target is often missed. Few studies have examined the prevalence or causes of delay. We describe the median time to antibiotic administration at our institution, predictors of delay, and barriers to prompt administration to inform quality improvement strategies.

Procedure

A random sample of 50 episodes of FN presenting to the emergency department (ED) between 2008 and 2009 were reviewed. Times between triage, MD assessment, lab results, and antibiotic administration were recorded. Patient and ED variables were examined as possible predictors of delay. In parallel, lean methodology was used to identify system inefficiencies. A trained moderator conducted group interviews with interdisciplinary representatives involved in the emergency care of neutropenic patients to identify process barriers to prompt antibiotics.

Results

The median time from triage to antibiotics was 216 minutes (interquartile range [IQR] = 151–274 minutes). The greatest delay occurred following the reporting of lab results (152 minutes, IQR = 84–210 minutes). Only fall season predicted a longer time to antibiotics (P = 0.03). The lean process identified unnecessary areas of delay between departments.

Conclusions

Time to antibiotic administration exceeded 1 hour. The chart review and lean process suggested targets for educational and infrastructural interventions, including an ED pre‐printed order sheet, targeted combined subspecialty education between emergency and hematology/oncology staff, and family education. A mixed methodology approach represents a model for improving process efficiency and meeting “best‐practice” targets in medicine. Pediatr Blood Cancer 2012;59:431–435. © 2011 Wiley Periodicals, Inc.
Pediatric oncology research in low income countries: Ethical concepts and challenges
Authors: Denburg Avram E. , Joffe Steven , Gupta Sumit , Howard Scott C. , Ribeiro Raul C. , Antillon Federico A. , Vasquez Roberto , Sung Lillian
Published: December 2011

Uneven strides in research and care have led to discrepancies in childhood cancer outcomes between high and low income countries (LICs). Collaborative research may help improve outcomes in LICs by generating knowledge for local scientific communities, augmenting knowledge translation, and fostering context‐specific evaluation of treatment protocols. However, the risks of such research have received little attention. This paper investigates the relationship between pediatric oncology research in LICs and four core issues in the ethics literature: standard of care, trial benefits, ethics review, and informed consent. Our aims are to highlight the importance of this field and the need for further inquiry. Pediatr Blood Cancer 2012; 58: 492–497. © 2011 Wiley Periodicals, Inc.
Fabrication of 3D electrospun structures from poly(lactide‐co‐glycolide acid)–nano‐hydroxyapatite composites
Authors: Leung Linus H. , Fan Stephanie , Naguib Hani E.
Published: December 2011

The fabrication of three‐dimensional (3D) electrospun composite scaffolds was presented in this study. Layers of electrospun meshes made from composites of poly(lactide‐co‐glycolide acid) (PLGA) and hydroxyapatite (HA) were stacked and sintered using pressurized gas. Three HA concentrations of 5, 10, and 20 wt % were tested, and the addition of the HA nanoparticles decreased the tensile mechanical properties of the meshes with 20 wt % HA. However, after the gas absorption process, the fibers within the mesh sintered, which improved the mechanical properties more than twofold. The fabrication of 3D, porous, electrospun scaffolds was also demonstrated. The resulting 3D scaffolds had open porosity of up to 70% and modulus of ∼20 MPa. This technique improves on the current electrospinning technology by overcoming the challenges of depositing a thick, 3D structure. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011
Core extractable nano‐objects: Manipulating triblock copolymer micelles
Authors: Gao Lei , Zhang Ke , Peng Bo , Shi Yi , Chen Yongming
Published: December 2011

We report manipulation of polymer nano‐objects by changing solvents through chemically crosslinking the spherical micelles of poly(3‐(triethoxysilyl)propyl methacrylate)‐block‐polystyrene‐block‐poly(2‐vinylpyridine) (PTEPM‐b‐PS‐b‐P2VP). In methanol, which is a common solvent of PTEPM and P2VP but poor of PS, PTEPM‐b‐PS‐b‐P2VP forms micelles with a PS core. When changing the medium into acidic water, the PTEPM segments further collapse and gelate to form a crosslinked shell outside of the PS core. When the particles are re‐dispersed into tetrahydrofuran (THF), the PS segments are extracted out, producing uniform small cavity of few nanometers in each particle. Thus one sample can be used to generate well‐defined nano‐objects with different appearance by solvent manipulation. The particle structure development has been characterized by transmission electron microscope (TEM), DLS, and 1H NMR. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
In situ Quartz Crystal Microbalance Measurements of Thin Protein Film Plasma Removal
Authors: Fumagalli Francesco , Hanuš Jan , Kylián Ondřej , Rossi François
Published: December 2011

Surgical instruments are intended to come into direct contact with the patients' tissue and thus need to be sterilized and decontaminated in order to prevent infections, inflammations or transmission of diseases. In this study, plasma interactions with low contamination levels (typically less than 3 µg · mm−2) of BSA proteins were investigated in situ by means of quartz crystal microbalance. Mass removal rates were found to depend on treatment time showing a self‐limiting behavior. Removal rates kinetics were characterized by descriptive parameters and correlated with plasma induced chemical composition changes and morphological modification of the protein film.

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Detonation Velocity Deficits and Curvature Radius of Mild Detonation Cords
Authors: Ye Yao‐Kun , Wen Yu‐Quan , Yan Nan
Published: December 2011

In order to study the detonation velocity deficits of wound mild detonation cords, a physical model and a theoretical mathematical equation for detonation velocity deficits of wound mild detonation cords were established based on the detonation wave’s corner effects and delay time phenomenon by using non‐dimensional analysis method. Besides, a semi‐empirical formula for detonation velocity deficit of wound mild detonation cords in the same charge size was obtained through experiments and curve fitting. Both the theoretical mathematical equation and the semi‐empirical formula show that the detonation velocity deficit of wound mild detonation cords and the reciprocal of the curvature radius have an exponential relationship.
Non‐Isothermal Kinetic Study of the Thermal Decomposition of Melamine 3‐Nitro‐1,2,4‐triazol‐5‐one Salt
Authors: Najafi Mostafa , Samangani Ayatallah Kalantari
Published: December 2011

Study on thermal behavior of 3‐nitro‐1,2,4‐triazol‐5‐one (NTO) salts was required to obtain important data for application purposes. These compounds have been shown to be useful intermediates for gun propellant ingredients, high energetic ballistic modifiers for solid propellants and other potential applications. In this paper, thermal decomposition and non‐isothermal kinetics of melamine 3‐nitro‐1,2,4‐triazol‐5‐one salt (MNTO) were studied under non‐isothermal conditions by DSC and TG methods. The kinetic parameters were obtained from analysis of the DSC and TG curves by Kissinger and Ozawa methods. The critical temperature of thermal explosion (Tb) was 574 K. The results show that MNTO is thermally more stable than NTO when compared in terms of the critical temperature of thermal explosion. Finally, the values of ΔS#, ΔH#, and ΔG# of its decomposition reaction were calculated.
Thermodynamic stability of BaTiO3 (110) surfaces
Authors: Wang J. , Tang G. , Wu X. S.
Published: December 2011

The surface stability of five terminations (BaTiO, TiO, Ba, O2, and O) for the polar (110) BaTiO3 surface is systematically studied by first‐principle calculations. The surface grand potential is calculated and compared, taking into account the influence of the chemical environment as function of the relative chemical potential. The complete phase diagram of the ternary system is presented. The Ba‐terminated BaTiO3 (110) surface has a surface grand potential close to that for the BaO‐terminated (100) surface at 0 K under Ba‐rich conditions, which indicates that both (110) and (100) BaTiO3 surfaces can exist simultaneously in perovskite ceramics.
Effects of Maple (Acer) Plant Part Extracts on Proliferation, Apoptosis and Cell Cycle Arrest of Human Tumorigenic and Non‐tumorigenic Colon Cells
Authors: González‐Sarrías Antonio , Li Liya , Seeram Navindra P.
Published: December 2011

Phenolic‐enriched extracts of maple sap and syrup, obtained from the sugar and red maple species (Acer saccharum Marsh, A. rubrum L., respectively), are reported to show anticancer effects. Despite traditional medicinal uses of various other parts of these plants by Native Americans, they have not been investigated for anticancer activity. Here leaves, stems/twigs, barks and sapwoods of both maple species were evaluated for antiproliferative effects against human colon tumorigenic (HCT‐116, HT‐29, Caco‐2) and non‐tumorigenic (CCD‐18Co) cells. Extracts were standardized to total phenolic and ginnalin‐A (isolated in our laboratory) levels. Overall, the extracts inhibited the growth of the colon cancer more than normal cells (over two‐fold), their activities increased with their ginnalin‐A levels, with red > sugar maple extracts. The red maple leaf extract, which contained the highest ginnalin‐A content, was the most active extract (IC50 = 35 and 16 µg/mL for extract and ginnalin‐A, respectively). The extracts were not cytotoxic nor did they induce apoptosis of the colon cancer cells. However, cell cycle analyses revealed that the antiproliferative effects of the extracts were mediated through cell cycle arrest in the S‐phase. The results from the current study suggest that these maple plant part extracts may have potential anticolon cancer effects. Copyright © 2011 John Wiley & Sons, Ltd.
Field‐scale evaluation of a biobarrier for the treatment of a trichloroethene plume
Authors: MacFarlane Kim D. , Cacciatore David A. , Leigh Daniel P. , Yurovsky Michael G. , Atta Amena
Published: December 2011

In the 1960s, trichloroethene (TCE) was used at what is now designated as Installation Restoration Program Site 32 Cluster at Vandenberg Air Force Base to flush missile engines prior to launch and perhaps for other degreasing activities, resulting in releases of TCE to groundwater. The TCE plume extends approximately 1 kilometer from the previous launch facilities beyond the southwestern end of the site. To limit further migration of TCE and chlorinated degradation by‐products, an in situ, permeable, reactive bioremediation barrier (biobarrier) was designed as a cost‐effective treatment technology to address the TCE plume emanating from the source area. The biobarrier treatment would involve injecting carbon‐based substrate and microbes to achieve reductive dechlorination of volatile organic compounds, such as TCE. Under reducing conditions and in the presence of certain dechlorinating microorganisms, TCE degrades to nontoxic ethene in groundwater.

To support the design of the full‐scale biobarrier, a pilot test was conducted to evaluate site conditions and collect pertinent design data. The pilot test results indicated possible substrate delivery difficulties and a smaller radius of influence than had been estimated, which would be used to determine the final biobarrier well spacing. Based on these results, the full‐scale biobarrier design was modified. In January 2010, the biobarrier was implemented at the toe of the source area by adding a fermentable substrate and a dechlorinating microbial culture to the subsurface via an injection well array that spanned the width of the TCE plume.

After the injections, the groundwater pH in the injection wells continued to decrease to a level that could be detrimental to the population of Dehalococcoides in the SDC‐9TM culture. In addition, 7 months postinjection, the injection wells could not be sampled due to fouling. Cleaning was required to restore their functions. Bioassay and polymerase chain reaction analyses were conducted, as well as titration tests, to assess the need for biobarrier amendments in response to the fouling issues and low pH. Additionally, slug tests were performed on three wells to evaluate possible localized differences in hydraulic conductivity within the biobarrier. Based on the test results, the biobarrier was amended with sodium carbonate and inoculated a second time with SDC‐9TM. The aquifer pH was restored, and reductive dechlorination resumed in the treatment zone, evidenced by the reduction in TCE and the increase in degradation products, including ethene. © 2011 Wiley Periodicals, Inc.
Full‐scale bioremediation of a dilute 50‐acre plume
Authors: Falatko David M. , Fam Sami A. , Blackburn Jason , McGillicuddy Glenn , Pon George , Gaudette Michael
Published: December 2011

Enhanced anaerobic dechlorination is being conducted to remediate a 50‐acre groundwater area impacted with chlorinated volatile organic compounds (CVOCs). The plume, which is over 3,000 feet (ft) long, initially contained tetrachloroethene and breakdown products at concentrations of 2 to 3 milligrams per liter. The site's high groundwater flow velocity (greater than 1,000 ft per year) was incorporated into the design to help with amendment distribution. Bioaugmentation was conducted using a mixed culture containing Dehalococcoides ethenogenes. There is evidence that it has migrated to distances exceeding 600 ft. The major benefit of the high groundwater flow velocity is greater areal coverage by the remediation system, but the downside is the difficulty in delivering sufficient donor to create the required anaerobic conditions. Overall performance has been excellent with total CVOC reductions and conversion to ethene of 98 percent within a 25‐acre area downgradient of the treatment transect that has operated the longest. © 2011 Wiley Periodicals, Inc.
Distributed consensus control for multi‐agent systems using terminal sliding mode and Chebyshev neural networks
Authors: Zou An‐Min , Kumar Krishna Dev , Hou Zeng‐Guang
Published: December 2011

This paper investigates the problem of consensus tracking control for second‐order multi‐agent systems in the presence of uncertain dynamics and bounded external disturbances. The communication ﬂow among neighbor agents is described by an undirected connected graph. A fast terminal sliding manifold based on lumped state errors that include absolute and relative state errors is proposed, and then a distributed finite‐time consensus tracking controller is developed by using terminal sliding mode and Chebyshev neural networks. In the proposed control scheme, Chebyshev neural networks are used as universal approximators to learn unknown nonlinear functions in the agent dynamics online, and a robust control term using the hyperbolic tangent function is applied to counteract neural‐network approximation errors and external disturbances, which makes the proposed controller be continuous and hence chattering‐free. Meanwhile, a smooth projection algorithm is employed to guarantee that estimated parameters remain within some known bounded sets. Furthermore, the proposed control scheme for each agent only employs the information of its neighbor agents and guarantees a group of agents to track a time‐varying reference trajectory even when the reference signals are available to only a subset of the group members. Most importantly, finite‐time stability in both the reaching phase and the sliding phase is guaranteed by a Lyapunov‐based approach. Finally, numerical simulations are presented to demonstrate the performance of the proposed controller and show that the proposed controller exceeds to a linear hyperplane‐based sliding mode controller. Copyright © 2011 John Wiley & Sons, Ltd.
Strategic entrepreneurship in family business
Authors: Lumpkin G. T. , Steier Lloyd , Wright Mike
Published: December 2011

The purpose of this special issue is to promote research on the role of family in nurturing entrepreneurial ventures as well as on the importance of strategic entrepreneurship in maintaining the strength and viability of established and multigenerational family firms. Two related research questions are at the heart of this inquiry: (1) In what ways does the influence of family matter to strategic entrepreneurship?; and (2) How can strategic entrepreneurship contribute to understanding and strengthening family firms? We begin this introductory paper by providing a brief overview of the contributions of each of the papers in this issue. We then develop a framework for addressing the role of family firms in strategic entrepreneurship that highlights the input‐process‐output nature of strategic entrepreneurship in family business and the contexts in which they occur. We conclude by outlining a research agenda for future research in this area along the themes relating to this framework. Copyright © 2011 Strategic Management Society.
Perspectives on the RNA polymerase II core promoter
Authors: Kadonaga James T.
Published: December 2011

The RNA polymerase II core promoter is sometimes referred to as the gateway to transcription. The core promoter is generally defined to be the stretch of DNA that directs the initiation of transcription. This simple description belies a complex multidimensional regulatory element, as there is considerable diversity in core promoter structure and function. Core promoters can be viewed at the levels of DNA sequences, transcription factors, and biological networks. Key DNA sequences are known as core promoter elements, which include the TATA box, initiator (Inr), polypyrimidine initiator (TCT), TFIIB recognition element (BRE), motif ten element (MTE), and downstream core promoter element (DPE) motifs. There are no universal core promoter elements that are present in all promoters. Different types of core promoters are transcribed by different sets of transcription factors and exhibit distinct properties, such as specific interactions with transcriptional enhancers, that are determined by the presence or absence of particular core promoter motifs. Moreover, some core promoter elements have been found to be associated with specific biological networks. For instance, the TCT motif is dedicated to the transcription of ribosomal protein genes in Drosophila and humans. In addition, nearly all of the Drosophila Hox genes have a DPE motif in their core promoters. The complexity of the core promoter is further seen in the relation among transcription initiation patterns, the stability or lability of transcriptional states, and the organization of the chromatin structure in the promoter region. Hence, the current data indicate that the core promoter is a critical component in the regulation of gene activity. WIREs Dev Biol 2012, 1:40–51 doi: 10.1002/wdev.21

This article is categorized under:

Gene Expression and Transcriptional Hierarchies > Regulatory Mechanisms

Gene Expression and Transcriptional Hierarchies > Gene Networks and Genomics
Synthesis and Characterisation of Schiff Base‐like Iron(II) Complexes with Imidazole as Axial Ligand
Authors: Lochenie Charles , Bauer Wolfgang , Schlamp Stephan , Thoma Peter , Weber Birgit
Published: December 2011

Four new six‐coordinate and one pentacoordinate iron(II) complexes with imidazole as axial ligand were synthesised and characterised. For two of the complexes crystals suitable for X‐ray structure analysis were obtained and an extended network of hydrogen bonds was observed in both cases. Magnetic susceptibility studies revealed, that two of the octahedral complexes are high‐spin complexes in the entire temperature range, whereas for the other two gradual spin transitions are observed.
Combination of Dexamethasone and Tropisetron Before Thyroidectomy to Alleviate Postoperative Nausea, Vomiting, and Pain: Randomized Controlled Trial
Authors: Zhou Haiyang , Xu Haitao , Zhang Jian , Wang Weijun , Wang Yi , Hu Zhiqian
Published: December 2011

Background

Nausea, vomiting, and pain frequently occur after thyoidectomy. Little evidence exists regarding the effects of administrating a combination of dexamethasone and tropisetron to patients undergoing thyroidectomy. We aimed to evaluate the effects of dexamethasone and tropisetron on thyroidectomy outcomes.

Methods

A total of 150 patients undergoing thyroidectomy were included in this prospective randomized, controlled, three‐arm study (group D: 8 mg dexamethasone; group T: 5 mg tropisetron; group D+T: 8 mg dexamethasone and 5 mg tropisetron). There were 50 patients in each group. Nausea, vomiting, pain, and the amount of antiemetic and analgesic agents required were recorded 2, 4, 8, 16, 24, 36, and 48 h postoperatively.

Results

The complete response rate of nausea and vomiting was significantly higher in group D+T (78%, 39/50), compared with that in group D (58%, 29/50) or group T (66%, 33/50) (P = 0.01). The incidence and severity of nausea in group D+T were significantly lower than in group D and group T, with the difference mainly occurring in the late postoperative period (6–48 h). The severity of postoperative pain was significantly less in the dexamethasone‐containing groups (D and D+T groups) than in the tropisetron group.

Conclusions

The combination of dexamethasone and tropisetron offers better prophylaxis for nausea, vomiting, and pain than either drug alone in patients undergoing thyroidectomy, especially during the late period (6–48 h).
The impact of seed dispersal by black and gold howler monkeys on forest regeneration
Authors: Bravo Susana Patricia
Published: December 2011

In Neotropical humid forest, the majority of tree species have seeds dispersed by vertebrates. Seed deposition by vertebrates is often spatially aggregated and a low per capita survival for seeds and seedlings is predicted. However, mortality factors could be saturated by high densities. I evaluated whether recruitment of saplings of species dispersed by black and gold howlers (Alouatta caraya) in latrines is higher than at control sites: (1) below parent trees, (2) in trees not used by monkeys to sleep, (3) randomly chosen sites within the forest, and determined whether howlers may influence current floristic composition of the Paraná River flooded forest. I recorded saplings several years old in the territories of five monkey groups. In total, I found four times more saplings in latrines than in the other areas, and results suggest that latrines are recruitment foci for most species, though larger samples would be required to assess this for every species. Frequency distribution of the diameter of tallest saplings of more abundant species reflected recruitment over time. I found saplings of more species growing in latrines than outside of them. Saplings higher than 1 m of two species of laurels (Ocotea diospyrifoliaandNectandra megapotamica) and one species of Myrtaceae (Eugenia punicifolia) had higher densities in latrines than below parent trees. Results suggest that mortality factors were saturated in latrines and that sapling may grow at a higher rate in latrines. In relation to the influence on floristic compositionE. burkartiana, an uncommon species in the forest, could increase in abundance as consequence of seed dispersal by howlers.
Historical Amnesia: The Humphrey-Hawkins Act, Full Employment and Employment as a Right
Authors: Ginsburg Helen Lachs
Published: December 2011

Economist William A. Darity has proposed a federal job guarantee with decent wages for all job seekers, an idea with deep, but largely forgotten, roots in US history. The article briefly explores some New Deal job-creation efforts and President Franklin Roosevelt's proposal for an Economic Bill of Rights. It then focuses on two major attempts to secure full employment through legislation. The Full Employment Bill of 1945 was defeated; the compromise, the Employment Act of 1946 did not have full employment as its goal. After years of struggle, a much-weakened Humphrey-Hawkins Full Employment and Balanced Growth Act of 1978 passed, but then was violated and virtually ignored. Full employment shifts power from capital to labor, so major opposition can be expected from efforts to obtain it. Proponents need more power and a strong movement, including at the grassroots level, pushing for jobs for all–not just jobs for me or my group. Publicizing the benefits of past job programs and reintroducing the idea of a decent-paying job as a right are suggested, as well as making decent jobs for all the center of economic policy. This requires a fundamental break with neoliberalism and reallocating political power away from big business and Wall Street toward middle and working-class people and the working- and non-working poor.
Is there a Need for an Undergraduate Urological Curriculum?
Authors: Scotta R. , Sinclair A.M. , Pearce I.
Published: December 2011

Objectives:

To review Medical student education in urology and assess students self reported knowledge and management competency of common urological conditions. To determine the degree of undergraduate exposure to urology and students intentions to follow a post graduate career in urology.

Methods:

Questionnaires were completed by final year medical students prior to final examinations over a five year period to assess exposure to undergraduate urology and consideration of urology as a postgraduate career. Students from a single year were asked to rate their knowledge and management competency with respect to a variety of common urological pathologies.

Results:

Students reported low levels of confidence to manage common and emergency urological conditions. Undergraduate exposure to urology is decreasing year on year, with fewer and fewer students considering urology as a future career option.

Conclusions:

Undergraduate exposure to urology is poor and as a consequence of this, fewer students are considering a career in urology. This trend needs to be reversed, possibly in part, by the implementation of a defined undergraduate urological curriculum and BAUS needs to foster a greater undergraduate presence to stimulate current medical undergraduates to consider a urological career.
Vortex development behind a finite porous obstruction in a channel
Authors: Zong Lijun , Nepf Heidi
Published: December 2011

This experimental study describes the turbulent wake behind a two-dimensional porous obstruction, consisting of a circular array of cylinders. The cylinders extend from the channel bed through the water surface, mimicking a patch of emergent vegetation. Three patch diameters ($D$) and seven solid volume fractions ($\Phi $) are tested. Because flow can pass through the patch, directly downstream there is a region of steady, non-zero, streamwise velocity, ${U}_{1} $, called the steady wake. For the patch diameters and solid volume fractions considered here, ${U}_{1} $ is a function of $\Phi $ only. The length of the steady wake (${L}_{1} $) increases as $\Phi $ decreases and can be predicted from the growth of a plane shear layer. The formation of the von-Kármán vortex street is delayed until the end of the steady wake. There are two regions of elevated transverse velocity fluctuation (${v}_{\mathit{rms}} $): directly behind the patch, associated with the wake turbulence of individual cylinders; and at the distance ${L}_{1} $ from the patch, associated with the formation of large-scale wake oscillation. Velocity along the centreline of the wake starts to increase only after the patch-scale vortex street is formed, and it approaches the free-stream velocity over a distance ${L}_{2} $. The dimensionless length of the entire wake, $({L}_{1} + {L}_{2} )/ D$, increases with patch porosity.