bluuebunny/crossref_metadata_2025 huggingface dataset:
Contrasting sapling bark allocation of five southeastern USA hardwood tree species in a fire prone ecosystem
Authors: Hammond Darcy H. , Varner J. Morgan , Kush John S. , Fan Zhaofei
Published: July 2015

Fire affects numerous aspects of plant growth and anatomy, particularly in those species adapted to persist in fire‐prone environments. A key aspect of tree survival is rapid accumulation of protective bark within fire return intervals. We compared bark accumulation in five co‐occurring hardwood species within a longleaf pine (Pinus palustris) ecosystem in the mountains of northeastern Alabama, USA. Sampled species included blackjack oak (Quercus marilandica), sand hickory (Carya pallida), common persimmon (Diospyros virginiana), rock chestnut oak (Quercus montana), and red maple (Acer rubrum). Using bark thickness and inside bark diameter measurements taken at 20‐cm intervals along the main stem of saplings (average age 4–5 years) we found that, while average wood diameter did not differ across species, significant differences occurred in the ratio of bark to wood. Bark comprised over half (bark:wood = 0.55) of the basal diameter of blackjack oak, which was 3×, 4×, and 6× greater than the bark:wood ratio of sand hickory and rock chestnut oak, common persimmon, and red maple, respectively. Bark taper revealed that while other species allocated similarly to bark along the length of their stem, blackjack oak allocated much more at its base (in the flaming zone) and relatively less as height increased. Red maple, a commonly cited invader during fire‐free intervals, invested the least in bark thickness and, with rock chestnut oak, had an average height and height:diameter ratio significantly greater than blackjack oak and all other species, respectively. These results confirm the adaptive importance of bark thickness to enhancing species survival in frequent fire regimes.
A Robust Geochemical Simulator To Model Improved-Oil-Recovery Methods
Authors: Luo Haishan , Al-Shalabi Emad W. , Delshad Mojdeh , Panthi Krishna , Sepehrnoori Kamy
Published: July 2015

The interest in modeling geochemical reactions has increased significantly for different improved-oil-recovery processes such as alkali/surfactant/polymer (ASP) flood, low-salinity waterflood, and ethylenediaminetetraacetic acid (EDTA) injection as a sacrificial agent in hard brine. Numerical simulation of multiphase flow coupled with geochemical reactions is challenging because of complex and coupled aqueous, aqueous/solid, and aqueous/oleic reactions. These reactions have significant impact upon oil recovery, and hence a robust geochemical simulator is important.

UTCHEM (2000) is a chemical-flooding reservoir simulator with geochemical-modeling capability. Nevertheless, one major limitation in the geochemical-reactive engine of UTCHEM is assuming the activities of reactive species is equal to unity. In fact, the activity coefficients are strongly nonlinear functions of the ionic strength of solution. One approach to tackle this deficiency was to couple UTCHEM (flow and transport) with IPhreeqc (a geochemical reactive engine) (Kazemi Nia Korrani et al. 2013). However, the simulator proved to be computationally expensive. Therefore, it is desirable to improve the geochemical- reactive engine within UTCHEM.

This paper presents the improvement of the geochemical-reactive engine in UTCHEM including implementing different activity-coefficient models for different reactive species, cation-exchange reactions, and numerical convergence. Certain unknown concentrations are eliminated from the elemental mass-balance equations and the reaction equations to reduce the computational burden. The Jacobian matrix and right-hand side of the linear-system equation in the Newton-Raphson method are updated accordingly in the Newton-Raphson method for performing the batch-reaction calculation.

A low-salinity-waterflood case is presented to validate the updated UTCHEM against PHREEQC (Parkhurst and Appelo 1999) and UTCHEM-IPhreeqc. The simulation studies indicated that the updated geochemical simulator succeeds in tackling the inaccuracy concerned in the original UTCHEM. Also, the updated version is more efficient compared with PHREEQC and UTCHEM-IPhreeqc with the same degree of accuracy. The updated geochemical simulator is then applied to model an ASP coreflood in which EDTA is used as a sacrificial agent to chelate calcium and magnesium ions. The experimental data of pH, oil recovery, and pressure drop were successfully history matched with predictions of the effluent concentrations of calcium and magnesium ions. A synthetic 3D ASP pilot case is successfully simulated considering effects of acid equilibrium reaction constant on oil recovery.
Early Weaning Reduces Rangeland Herbage Disappearance
Authors: Johnson Patricia S. , Olson Kenneth C. , Gates Roger N. , Patterson Hubert H. , Hubert Mindy , Landblom Douglas , Kincheloe Janna J. , Richter Heather A. , Grove Allison V.
Published: July 2015

Early weaning of beef calves reduces nutrient and forage demand in a cow–calf enterprise, potentially contributing to reduction in forage utilization on the pasture from which calves are removed by a nonlactating cow vs. a cow–calf pair. Research was conducted to evaluate weaning beef calves 90 days early (EW) vs. normal weaning (NW) on pasture herbage disappearance in mixed‐grass prairie pastures in the northern Great Plains. Spring‐calving cows (n = 48) were utilized in each study year (2003, 2004, and 2006) from the date of early weaning (August) until the date of normal weaning (November). Cow–calf pairs were randomly assigned each year to each NW pasture (n = 8 pasture–1); cows whose calves had been weaned early were randomly assigned to each EW pasture (n = 8 pasture–1). No calves grazed EW pastures. Cattle were weighed and body condition scored at the beginning and end of each trial period. Available herbage was determined before and after grazing in each pasture. The effect of weaning treatment on cow average daily gain and body condition score change was highly significant (P < 0.001). Early‐weaned cows gained weight and condition; normal‐weaned cows lost weight and condition. Herbage disappearance was lower (P = 0.017) in EW than NW pastures, resulting in 18.9 lb cow–1 day–1, or 36%, herbage savings. This is equivalent to an additional 1.1 month of grazing saved per animal unit over a 90‐day period. The value of the additional animal‐unit months includes extending the grazing season, increasing cow numbers, or as “banked” forage for drought management.
Inheritance of Aposporous Apomixis in Inter‐specific Hybrids Derived from Sexual Paspalum plicatulum and Apomictic Paspalum guenoarum
Authors: Aguilera Patricia Mabel , Galdeano Florencia , Quarin Camilo Luis , Amelio Ortiz Juan Pablo , Espinoza Francisco
Published: July 2015

Apomictic Paspalum plicatulum Michx. and P. guenoarum Arechav. are promising candidates for forage grass development in tropical regions. From a plant breeding perspective, apomixis provides a unique mechanism for developing superior cultivars and preserving them indefinitely. Therefore, analysis of its inheritance is of great interest in these apomictic species. The objective of this work was to analyze the inheritance and expressivity of apomixis in interspecific families derived from crosses between a sexual colchicine‐induced plant of P. plicatulum and an apomictic P. guenoarum plant. One F1, one F2, and three backcross (BC) populations were created. Amplified fragment‐length polymorphism (AFLP) markers confirmed the hybrid origin of the F1 descendants. Analysis of the reproductive mode of the F1 by flow cytometry seed screen (FCSS) showed a segregation ratio of 1.6:1 sexual vs. apomictic plants. The same analysis in F2 and BC populations showed that in selfing or crosses involving sexual genotypes all progeny reproduced by sexuality, while BC populations involving apomictic hybrids as pollen donors produced offspring that segregated for the reproductive mode. Apomixis can be transmitted by pollen from P. guenoarum to other species of the Plicatula group as a simplex (Aaaa) Mendelian dominant factor, and full sexual reproduction requires the homozygous recessive (nulliplex) condition (aaaa) for the apomixis determinant. Results provided here are of interest for breeding apomictic species of Plicatula and for basic research on the genetic determinants of apomixis. Also, the possibility of creating new apomictic cultivars by traditional breeding methods is presented.
Identification of Quantitative Trait Loci for Alfalfa Forage Biomass Productivity during Drought Stress
Authors: Ray Ian M. , Han Yuanhong , E Lei , Meenach Chris D. , Santantonio Nicholas , Sledge Mary K. , Pierce Christopher A. , Sterling Tracy M. , Kersey Rossio K. , Bhandari Hem Singh , Monteros Maria J.
Published: July 2015

Large portions of the world's arable acreage experience water stress on a regular basis. Improving crop productivity in such drought‐prone environments is a critical breeding objective. The goal of this study was to detect quantitative trait loci (QTL) associated with alfalfa (Medicago sativa L.) forage productivity during drought stress. Two first‐generation backcross (BC1) mapping populations (n = 253) derived from a cross between M. sativa subsp. sativa and M. sativa subsp. falcata were used to develop an updated tetraploid (2n = 4x = 32) genetic linkage map constructed from 600 single‐dose allele molecular markers. Map lengths associated with the two populations were 1293 and 1049 cM, with an average marker density of 3.8 and 3.9 cM, respectively. Half‐sib families derived from 206 BC1 individuals were evaluated for forage yield in seeded plots in seven water‐stressed environments in New Mexico and Oklahoma, USA. Significant genotype effects were detected within each population and environment. Interval mapping analysis identified 10 and 15 QTL that, respectively, improved or reduced forage yield during drought. Average phenotypic effects of each QTL on biomass yield ranged from 3 to 6% and the direction of these effects were generally consistent over environments. Desirable alleles identified in these parents may be suitable for marker‐aided introgression into elite populations to incrementally improve their forage productivity in water‐limited environments.
Association of Phenotypic Traits with Ploidy and Genome Size in Annual Ryegrass
Authors: Rios Esteban F. , Kenworthy Kevin E. , Munoz Patricio R.
Published: July 2015

Annual ryegrass (Lolium multiflorum Lamarck) is planted annually on more than 1 million ha of pastures in the southeastern United States. The exact ploidy level and genome size of the annual ryegrass germplasm collection (USDA–ARS, Germplasm Resources Information Network, GRIN) are unknown and the future use of this germplasm relies on their determination. The study was conducted to (i) estimate the ploidy level and determine the DNA content of 139 accessions from the GRIN collection, 15 experimental lines, and 13 commercial cultivars through flow cytometry; and (ii) identify morphological and agronomic characteristics that could be used to differentiate diploid from tetraploid annual ryegrass. A total of 140 diploid and 27 tetraploid lines were successfully identified through flow cytometry. The average 2C DNA content was 6.13 ± 0.36 pg for the diploid lines and 12.30 ± 0.83 pg for the tetraploids. Diploid and tetraploid annual ryegrass showed significant differences for morphological and agronomic variables such as seed size, leaf width and length, guard cell size, plant height, tiller size, plant biomass, and seed head length, and all variables were significantly correlated with DNA content. The use of morphological and agronomic variables may guide the determination of ploidy when flow cytometry is not available. Ploidy level and genome size information will benefit those that request accessions from the GRIN system for specific studies at the diploid or tetraploid level in the species.
Designing Selection Criteria for Use of Reed Canarygrass as a Bioenergy Feedstock
Authors: Casler Michael D. , Cherney Jerome H. , Charles Brummer E. , Dien Bruce S.
Published: July 2015

Reed canarygrass (Phalaris arundinacea L.) is a perennial C3 grass with a circumglobal distribution in the Northern Hemisphere and adaptation to a wide range of environmental conditions. This species is currently under development as a bioenergy feedstock in North America and Europe. Thus, the objectives of this study were to (i) quantify genetic variation for biomass quality traits of reed canarygrass cultivars and accessions, (ii) determine the relationships for biomass yield with reed canarygrass quality traits, and (iii) identify favorable and attainable breeding objectives for biomass yield and quality traits of reed canarygrass. Eighty cultivars or accessions were grown at five field locations and evaluated for 26 biomass quality traits in 2006 through 2008. Ignoring biomass quality traits in favor of the singular breeding objective of high biomass yield would be likely to result in a few favorable correlated responses including low N, low ash, low Cl, low Fe, and high enzymatic xylan conversion efficiency. These changes would not be sufficiently large to transform reed canarygrass into a more favorable bioenergy feedstock within a few generations of breeding. To do so will require a more focused effort with a relatively small number of traits, for example, high biomass yield, low ash, and high gross calorific value (GCV) for a thermochemical conversion platform or high biomass yield, low lignin, and high glucan and xylan conversion efficiencies for a fermentation platform.
Criminal law and mental illness
Authors: Stojanovic Zoran
Published: July 2015

The paper deals with the problem of criminal law reaction to behavior of
mentally ill, insane offenders who violate or threaten the criminal law
protected values. To the preliminary question of whether the criminal
reaction is generally justified in regard to quasi-criminal acts of mentally
ill persons (which are not criminal in the true sense because they lack mens
rea which is a constituent element of each offense), the answer is still yes.
There are no other, more appropriate forms of social control, or other legal
mechanisms that could more effectively than the criminal law, while
respecting the safeguards that have become indispensable in criminal law,
protect important goods of the individual or society from the harmful
behavior of mentally ill persons. Although the entire criminal law is based
on guilt and the subjective attitude of the offender towards the criminal
offense for which he is exposed to the social-ethical reprimand, it is
excluded in case of mentally ill, insane offenders and implementation of
appropriate security measures. Capabilities of criminal law in performing a
protective function relative to mentally ill offenders are certainly more
modest than in case of perpetrators who can be held accountable. The entire
general prevention (whether positive or negative) underlying protective
function of criminal law, is almost inconceivable in relation to potential
offenders who are mentally ill. Available options are reduced to detention
and psychiatric treatment of the mentally ill offender. The application of
security measures to insane, mentally ill persons is limited, therefore,
mainly to certain aspects of special prevention. Even exercising social
control through criminal law differs, significantly, depending on whether we
talk about incompetent, mentally ill persons or those who have normal mental
abilities.
A randomized controlled trial of self-perceived pain, discomfort, and impairment of jaw function in children undergoing orthodontic treatment with fixed or removable appliances
Authors: Wiedel Anna-Paulina , Bondemark Lars
Published: July 2015

Objective: 

To compare patients’ perceptions of fixed and removable appliance therapy for correction of anterior crossbite in the mixed dentition, with special reference to perceived pain, discomfort, and impairment of jaw function.

Material and Methods: 

Sixty-two patients with anterior crossbite and functional shift were recruited consecutively and randomized for treatment with fixed appliances (brackets and archwires) or removable appliances (acrylic plates and protruding springs). A questionnaire, previously found to be valid and reliable, was used for evaluation at the following time points: before appliance insertion, on the evening of the day of insertion, every day/evening for 7 days after insertion, and at the first and second scheduled appointments (after 4 and 8 weeks, respectively).

Results: 

Pain and discomfort intensity were higher for the first 3 days for the fixed appliance. Pain and discomfort scores overall peaked on day 2. Adverse effects on school and leisure activities were reported more frequently in the removable than in the fixed appliance group. The fixed appliance group reported more difficulty eating different kinds of hard and soft food, while the removable appliance group experienced more speech difficulties. No significant intergroup difference was found for self-estimated disturbance of appearance between the appliances.

Conclusions: 

The general levels of pain and discomfort were low to moderate in both groups. There were some statistically significant differences between the groups, but these were only minor and with minor clinical relevance. As both appliances were generally well accepted by the patients, either fixed or removable appliance therapy can be recommended.
Coexistent Chorangioma and Hepatic Adenoma in One Twin Placenta: A Case Report and Review of the Literature
Authors: Denapoli Thomas S.
Published: July 2015

Primary nontrophoblastic tumors of a placenta are very uncommon, with the majority being of vascular origin, such as chorangiomas and chorangiomatosis. Rare examples of tumor-like collections of liver tissue, morphologically consistent with hepatocellular adenomas, have been reported. We report the co-occurrence of a chorangioma and hepatic adenoma as a grossly single lesion on the fetal surface of a diamniotic dichorionic twin placenta.
Mediastinal Granular Cell Tumor in a 16-Year-Old Boy: A Surgical and Pathologic Perspective
Authors: Winchester Lacey M. , Puckett Yana , Greenspon Jose , Vogler Carole A.
Published: July 2015

Granular cell tumor is a benign tumor of likely neural or neuroectodermal origin that occurs most commonly in the subcutaneous tissues of the trunk, breast, and extremities of adults. Congenital gingival lesions comprise the majority of the pediatric granular cell tumors. Granular cell tumors are generally small and asymptomatic, and while 1 in 10 patients has multiple tumors, recurrence and malignancy are very rare. Mediastinal granular cell tumors have been reported, most occurring in young adult or middle-aged women. We present a case of a 16-year-old asymptomatic boy with a large mediastinal granular cell tumor incidentally identified after a motor vehicle accident, and we review the intraoperative, microscopic, and ultrastructural features of this tumor. Both the patient's age and anatomical location are unusual for this tumor, which presented technical and diagnostic challenges to the patient care team.
Evidence of Placental Hypoxia in Maternal Sleep Disordered Breathing
Authors: Ravishankar Sanjita , Bourjeily Ghada , Lambert-Messerlian Geralyn , He Mai , De Paepe Monique E. , Gündoğan Füsun
Published: July 2015

Sleep disordered breathing (SDB) represents a spectrum of disorders, including habitual snoring and obstructive sleep apnea (OSA). Sleep disordered breathing is characterized by chronic intermittent hypoxia, airflow limitation, and recurrent arousals, which may lead to tissue hypoperfusion, hypoxia, and inflammation. In this study, we aimed to examine whether SDB during pregnancy was associated with histopathologic evidence of chronic placental hypoxia and/or uteroplacental underperfusion. The placentas of women with OSA ( n = 23) and habitual snoring ( n = 78) as well as nonsnorer controls ( n = 47) were assessed for histopathologic and immunohistochemical markers of chronic hypoxia and uteroplacental underperfusion. Fetal normoblastemia was significantly more prevalent in SDB placentas than in those of nonsnorer controls (34.6% and 56.5% in snorers and OSA, respectively, versus 6.4% in controls). Expression of the tissue hypoxia marker carbonic anhydrase IX (CAIX) was more common in OSA placentas than controls (81.5% and 91.3% in snorers and OSA, respectively, versus 57.5% in controls). Adjusting for confounders such as body mass index, diabetes mellitus, or chronic hypertension did not alter the results. The uteroplacental underperfusion scores were similar among the 3 groups. Our findings suggest that SDB during pregnancy is associated with fetoplacental hypoxia, as manifested by fetal normoblastemia and increased placental carbonic anhydrase IX immunoreactivity. The clinical implications and underlying mechanisms remain to be determined.
Clinical Markers of the Intensity of Balance Challenge: Observational Study of Older Adult Responses to Balance Tasks
Authors: Farlie Melanie K. , Molloy Elizabeth , Keating Jennifer L. , Haines Terry P.
Published: July 2015

Background

Effective balance rehabilitation is critically important to the aging population. Optimal exercise prescription for balance rehabilitation has not been described, as there is no measure of balance exercise intensity. To rate the intensity of balance exercise, an item set is required.

Objectives

The aim of this study was to explore verbal and nonverbal markers that differentiated tasks of high, medium, and low balance intensity to inform the development of an instrument to measure the intensity of balance challenge.

Design

This was an observational study utilizing an interpretive description approach.

Methods

Twenty older adults were observed performing 3 balance tasks that challenged balance at low to high intensity. Verbal and nonverbal responses were recorded. After each task, participants were asked to describe the test experience. Data were analyzed to identify potential markers of balance challenge intensity.

Results

Markers of the intensity of balance challenge were grouped by time periods defined as pretask, in-task, and posttask. A key pretask finding was an increased delay to task commencement with increased task difficulty. Commencement delay was accompanied by talk in 19 of 21 instances. Physical markers of the intensity of balance challenge were grouped into 3 categories—bracing, postural reactions, and sway—and were increasingly observed as intensity of balance challenge increased. Participants described tasks as pushing them toward the limits of their balancing capacity as the intensity of balance challenge increased.

Conclusions

Verbal and nonverbal markers of the intensity of balance challenge in older adults performing balance tasks that differentiated high-intensity tasks from medium- to low-intensity tasks were identified. The pretask phase of balance exercise performance is an important diagnostic space, rich in verbal and nonverbal markers.
Clinical Tests of Standing Balance in the Knee Osteoarthritis Population: Systematic Review and Meta-analysis
Authors: Hatfield Gillian L. , Morrison Adam , Wenman Matthew , Hammond Connor A. , Hunt Michael A.
Published: July 2015

Background

People with knee osteoarthritis (OA) have a high prevalence of falls. Poor standing balance is one risk factor, but the extent of standing balance deficits in people with knee OA is unknown.

Purpose

The primary purpose of this study was to summarize available data on standing balance in people with knee OA compared with people without knee OA. A secondary purpose was to establish the extent of balance impairment across disease severity.

Data Sources

A literature search of the MEDLINE, EMBASE, CINAHL, and Web of Science databases through November 19, 2014, was conducted.

Study Selection

Studies on individuals with knee OA containing clinical, quantifiable measures of standing balance were included. Methodological quality was assessed by 2 reviewers using a 16-item quality index developed for nonrandomized studies. Studies scoring >50% on the index were included.

Data Extraction

Participant characteristics (age, sex, body mass index, OA severity, compartment involvement, unilateral versus bilateral disease) and balance outcomes were extracted by 2 reviewers. Standardized mean differences were pooled using a random-effects model.

Data Synthesis

The search yielded 2,716 articles; 8 met selection and quality assessment criteria. The median score on the quality index was 13/17. People with knee OA consistently performed worse than healthy controls on the Step Test, Single-Leg Stance Test, Functional Reach Test, Tandem Stance Test, and Community Balance and Mobility Scale. The pooled standardized mean difference was −1.64 (95% confidence interval=−2.58, −0.69). No differences were observed between varying degrees of malalignment, or between unilateral versus bilateral disease.

Limitations

No studies compared between-knee OA severities. Thus, expected changes in balance as the disease progresses remain unknown.

Conclusions

Few studies compared people with knee OA and healthy controls, but those that did showed that people with knee OA performed significantly worse. More research is needed to understand the extent of balance impairments in people with knee OA using easy-to-administer, clinically available tests.
Episodic ventriculomegaly due to hypernatremia mimicking shunt malfunction: case report
Authors: Jernigan Sarah C. , Stone Scellig S. D. , Aronson Joshua P. , Putman Melissa , Proctor Mark R.
Published: July 2015

Patients with shunted hydrocephalus presenting with altered mental status and ventriculomegaly are generally considered to be in shunt failure requiring surgical treatment. The authors describe a case of shunted hydrocephalus secondary to a disseminated neuroectodermal tumor in a pediatric patient in whom rapid fluctuations in sodium levels due to diabetes insipidus repeatedly led to significant changes in ventricle size, with invasively confirmed normal shunt function and low intracranial pressure. This clinical picture exactly mimics shunt malfunction, requires urgent nonsurgical therapy, and underscores the importance of considering serum osmolar abnormalities in the differential diagnosis for ventriculomegaly.
Molecular Imaging of Tumors Using a Quantitative T1 Mapping Technique via Magnetic Resonance Imaging
Authors: Herrmann Kelsey , Johansen Mette , Craig Sonya , Vincent Jason , Howell Michael , Gao Ying , Lu Lan , Erokwu Bernadette , Agnes Richard , Lu Zheng-Rong , Pokorski Jonathan , Basilion James , Gulani Vikas , Griswold Mark , Flask Chris , Brady-Kalnay Susann
Published: July 2015

Magnetic resonance imaging (MRI) of glioblastoma multiforme (GBM) with molecular imaging agents would allow for the specific localization of brain tumors. Prior studies using T1-weighted MR imaging demonstrated that the SBK2-Tris-(Gd-DOTA)3 molecular imaging agent labeled heterotopic xenograft models of brain tumors more intensely than non-specific contrast agents using conventional T1-weighted imaging techniques. In this study, we used a dynamic quantitative T1 mapping strategy to more objectively compare intra-tumoral retention of the SBK2-Tris-(Gd-DOTA)3 agent over time in comparison to non-targeted control agents. Our results demonstrate that the targeted SBK2-Tris-(Gd-DOTA)3 agent, a scrambled-Tris-(Gd-DOTA)3 control agent, and the non-specific clinical contrast agent Optimark™ all enhanced flank tumors of human glioma cells with similar maximal changes on T1 mapping. However, the retention of the agents differs. The non-specific agents show significant recovery within 20 min by an increase in T1 while the specific agent SBK2-Tris-(Gd-DOTA)3 is retained in the tumors and shows little recovery over 60 min. The retention effect is demonstrated by percent change in T1 values and slope calculations as well as by calculations of gadolinium concentration in tumor compared to muscle. Quantitative T1 mapping demonstrates the superior binding and retention in tumors of the SBK2-Tris-(Gd-DOTA)3 agent over time compared to the non-specific contrast agent currently in clinical use.
Chromatin Dynamics in Lineage Commitment and Cellular Reprogramming
Authors: Shchuka Virlana , Malek-Gilani Nakisa , Singh Gurdeep , Langroudi Lida , Dhaliwal Navroop , Moorthy Sakthi , Davidson Scott , Macpherson Neil , Mitchell Jennifer
Published: July 2015

Dynamic structural properties of chromatin play an essential role in defining cell identity and function. Transcription factors and chromatin modifiers establish and maintain cell states through alteration of DNA accessibility and histone modifications. This activity is focused at both gene-proximal promoter regions and distally located regulatory elements. In the three-dimensional space of the nucleus, distal elements are localized in close physical proximity to the gene-proximal regulatory sequences through the formation of chromatin loops. These looping features in the genome are highly dynamic as embryonic stem cells differentiate and commit to specific lineages, and throughout reprogramming as differentiated cells reacquire pluripotency. Identifying these functional distal regulatory regions in the genome provides insight into the regulatory processes governing early mammalian development and guidance for improving the protocols that generate induced pluripotent cells.
Possible Internalization of an Enterovirus in Hydroponically Grown Lettuce
Authors: Carducci Annalaura , Caponi Elisa , Ciurli Adriana , Verani Marco
Published: July 2015

Several studies have shown that enteric viruses can be transferred onto the surface of vegetables and fruits through spray irrigation, but, recently, reports have suggested viral contamination of vegetables sub-irrigated with reused wastewater. Hydroponic cultures, used to grow ready to eat fresh lettuce, have also been used to study the possibility of viral absorption through roots. This study was conducted to assess a possible risk of viral contamination in lettuce from contaminated water. The leaves of lettuce plants grown in hydroponic cultures where the roots were exposed to water containing Coxsakievirus B2, were analysed for evidence of the virus. The plants and water were sampled at different times and virus was measured using quantitative RT-PCR and infectivity assay. In leaf samples, the lowest observed infective data were lower than the qRT-PCR detection limits, suggesting that free viral RNA or damaged viruses are eliminated rapidly while infectious particles remain stable for a longer time. The obtained data revealed that the leaves were contaminated at a water concentration of 4.11 ± 1 Log Most Probable Number/L (8.03 ± 1 Log GC/L) a concentration observed in contaminated untreated water of wastewater treatment plants. However, the absorption dynamics and whether the virus is inactive in the leaves still remains to be clarified. Nevertheless, this work has practical implications for risk management in using reclaimed water for agricultural use; when irrigated vegetables are destined for raw consumption, virological contamination in water sources should be evaluated.
Study on Microbial Deposition and Contamination onto Six Surfaces Commonly Used in Chemical and Microbiological Laboratories
Authors: Tamburini Elena , Donegà Valentina , Marchetti Maria , Pedrini Paola , Monticelli Cecilia , Balbo Andrea
Published: July 2015

The worktops in both chemical and microbiological laboratories are the surfaces most vulnerable to damage and exposure to contamination by indoor pollutants. The rate at which particles are deposited on indoor surfaces is an important parameter to determine human exposure to airborne biological particles. In contrast to what has been established for inorganic pollutants, no limit has been set by law for microbial contamination in indoor air. To our knowledge, a comparative study on the effect of surfaces on the deposition of microbes has not been carried out. An evaluation of the microbial contamination of worktop materials could be of crucial importance, both for safety reasons and for the reliability of tests and experiments that need to be carried out in non-contaminated environments. The aim of this study was to evaluate the overall microbial contamination (fungi, mesophilic and psychrophilic bacteria, staphylococci) on six widely used worktop materials in laboratories (glass, stainless steel, fine porcelain stoneware, post-forming laminate, high-performing laminate and enamel steel) and to correlate it with the characteristics of the surfaces. After cleaning, the kinetics of microbial re-contamination were also evaluated for all surfaces.
Avian Conservation Areas as a Proxy for Contaminated Soil Remediation
Authors: Lin Wei-Chih , Lin Yu-Pin , Anthony Johnathen , Ding Tsun-Su
Published: July 2015

Remediation prioritization frequently falls short of systematically evaluating the underlying ecological value of different sites. This study presents a novel approach to delineating sites that are both contaminated by any of eight heavy metals and have high habitat value to high-priority species. The conservation priority of each planning site herein was based on the projected distributions of eight protected bird species, simulated using 900 outputs of species distribution models (SDMs) and the subsequent application of a systematic conservation tool. The distributions of heavy metal concentrations were generated using a geostatistical joint-simulation approach. The uncertainties in the heavy metal distributions were quantified in terms of variability among 1000 realization sets. Finally, a novel remediation decision-making approach was presented for delineating contaminated sites in need of remediation based on the spatial uncertainties of multiple realizations and the priorities of conservation areas. The results thus obtained demonstrate that up to 42% of areas of high conservation priority are also contaminated by one or more of the heavy metal contaminants of interest. Moreover, as the proportion of the land for proposed remediated increased, the projected area of the pollution-free habitat also increased. Overall uncertainty, in terms of the false positive contamination rate, also increased. These results indicate that the proposed decision-making approach successfully accounted for the intrinsic trade-offs among a high number of pollution-free habitats, low false positive rates and robustness of expected decision outcomes.
Climate Change, Drought and Human Health in Canada
Authors: Yusa Anna , Berry Peter , J.Cheng June , Ogden Nicholas , Bonsal Barrie , Stewart Ronald , Waldick Ruth
Published: July 2015

Droughts have been recorded all across Canada and have had significant impacts on individuals and communities. With climate change, projections suggest an increasing risk of drought in Canada, particularly in the south and interior. However, there has been little research on the impacts of drought on human health and the implications of a changing climate. A review of the Canadian, U.S. and international literature relevant to the Canadian context was conducted to better define these impacts and adaptations available to protect health. Drought can impact respiratory health, mental health, illnesses related to exposure to toxins, food/water security, rates of injury and infectious diseases (including food-, water- and vector-borne diseases). A range of direct and indirect adaptation (e.g., agricultural adaptation) options exist to cope with drought. Many have already been employed by public health officials, such as communicable disease monitoring and surveillance and public education and outreach. However, gaps exist in our understanding of the impacts of short-term vs. prolonged drought on the health of Canadians, projections of drought and its characteristics at the regional level and the effectiveness of current adaptations. Further research will be critical to inform adaptation planning to reduce future drought-related risks to health.
Stress-Responsive Expression, Subcellular Localization and Protein–Protein Interactions of the Rice Metacaspase Family
Authors: Huang Lei , Zhang Huijuan , Hong Yongbo , Liu Shixia , Li Dayong , Song Fengming
Published: July 2015

Metacaspases, a class of cysteine-dependent proteases like caspases in animals, are important regulators of programmed cell death (PCD) during development and stress responses in plants. The present study was focused on comprehensive analyses of expression patterns of the rice metacaspase (OsMC) genes in response to abiotic and biotic stresses and stress-related hormones. Results indicate that members of the OsMC family displayed differential expression patterns in response to abiotic (e.g., drought, salt, cold, and heat) and biotic (e.g., infection by Magnaporthe oryzae, Xanthomonas oryzae pv. oryzae and Rhizoctonia solani) stresses and stress-related hormones such as abscisic acid, salicylic acid, jasmonic acid, and 1-amino cyclopropane-1-carboxylic acid (a precursor of ethylene), although the responsiveness to these stresses or hormones varies to some extent. Subcellular localization analyses revealed that OsMC1 was solely localized and OsMC2 was mainly localized in the nucleus. Whereas OsMC3, OsMC4, and OsMC7 were evenly distributed in the cells, OsMC5, OsMC6, and OsMC8 were localized in cytoplasm. OsMC1 interacted with OsLSD1 and OsLSD3 while OsMC3 only interacted with OsLSD1 and that the zinc finger domain in OsMC1 is responsible for the interaction activity. The systematic expression and biochemical analyses of the OsMC family provide valuable information for further functional studies on the biological roles of OsMCs in PCD that is related to abiotic and biotic stress responses.
RGD Peptides-Conjugated Pluronic Triblock Copolymers Encapsulated with AP-2α Expression Plasmid for Targeting Gastric Cancer Therapy in Vitro and in Vivo
Authors: Wang Wei , Liu Zhimin , Sun Peng , Fang Cheng , Fang Hongwei , Wang Yueming , Ji Jiajia , Chen Jun
Published: July 2015

Gastric cancer, a high-risk malignancy, is a genetic disease developing from a cooperation of multiple gene mutations and a multistep process. Gene therapy is a novel treatment method for treating gastric cancer. Here, we developed a novel Arg-Gly-Asp (RGD) peptides conjugated copolymers nanoparticles-based gene delivery system in order to actively targeting inhibit the growth of gastric cancer cells. These transcription factor (AP-2α) expression plasmids were also encapsulated into pluronic triblock copolymers nanoparticles which was constituted of poly(ethylene glycol)-block-poly(propylene glycol)- block-poly(ethylene glycol) (PEO-block-PPO-block-PEO, P123). The size, morphology and composition of prepared nanocomposites were further characterized by nuclear magnetic resonance (NMR), transmission electron microscopy (TEM) and dynamic light scattering (DLS). In MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide) analysis, these nanocomposites have minor effects on the proliferation of GES-1 cells but significantly decreased the viability of MGC-803, suggesting they own low cytotoxicity but good antitumor activity. The following in vivo evaluation experiments confirmed that these nanocomposites could prevent the growth of gastric cancer cells in the tumor xenograft mice model. In conclusion, these unique RGD peptides conjugated P123 encapsulated AP-2α nanocomposites could selectively and continually kill gastric cancer cells by over-expression of AP-2α in vitro and in vivo; this exhibits huge promising applications in clinical gastric cancer therapy.
Experimental Evidence Shows Salubrinal, an eIF2α Dephosphorylation Inhibitor, Reduces Xenotoxicant-Induced Cellular Damage
Authors: Matsuoka Masato , Komoike Yuta
Published: July 2015

Accumulating evidence indicates that endoplasmic reticulum (ER) stress and the subsequent unfolded protein response (UPR) are involved in the pathogenesis of not only the protein misfolding disorders such as certain neurodegenerative and metabolic diseases, but also in the cytotoxicity of environmental pollutants, industrial chemicals, and drugs. Thus, the modulation of ER stress signaling pathways is an important issue for protection against cellular damage induced by xenotoxicants. The substance salubrinal has been shown to prevent dephosphorylation of the eukaryotic translation initiation factor 2 alpha (eIF2α). The phosphorylation of eIF2α appears to be cytoprotective during ER stress, because inhibition of the translation initiation activity of eIF2α reduces global protein synthesis. In addition, the expression of activating transcription factor 4 (ATF4), a transcription factor that induces the expression of UPR target genes, is up-regulated through alternative translation. This review shows that salubrinal can protect cells from the damage induced by a wide range of xenotoxicants, including environmental pollutants and drugs. The canonical and other possible mechanisms of cytoprotection by salubrinal from xenotoxicant-induced ER stress are also discussed.
Interferon-Beta Therapy of Multiple Sclerosis Patients Improves the Responsiveness of T Cells for Immune Suppression by Regulatory T Cells
Authors: Trinschek Bettina , Luessi Felix , Gross Catharina , Wiendl Heinz , Jonuleit Helmut
Published: July 2015

Multiple sclerosis (MS) is an inflammatory autoimmune disease characterized by imbalanced immune regulatory networks, and MS patient-derived T effector cells are inefficiently suppressed through regulatory T cells (Treg), a phenomenon known as Treg resistance. In the current study we investigated T cell function in MS patients before and after interferon-beta therapy. We compared cytokine profile, responsiveness for Treg-mediated suppression ex vivo and evaluated reactivity of T cells in vivo using a humanized mouse model. We found that CD4+ and CD8+ T cells of therapy-naive MS patients were resistant to Treg-mediated suppression. Treg resistance is associated with an augmented IL-6 production, enhanced IL-6 receptor expression, and increased PKB/c-Akt phosphorylation. These parameters as well as responsiveness of T cells to Treg-mediated suppression were restored after interferon-beta therapy of MS patients. Following transfer into immunodeficient mice, MS T cells induced a lethal graft versus host disease (GvHD) and in contrast to T cells of healthy volunteers, this aggressive T cell response could not be controlled by Treg, but was abolished by anti-IL-6 receptor antibodies. However, magnitude and lethality of GvHD induced by MS T cells was significantly decreased after interferon-beta therapy and the reaction was prevented by Treg activation in vivo. Our data reveals that interferon-beta therapy improves the immunoregulation of autoaggressive T effector cells in MS patients by changing the IL-6 signal transduction pathway, thus restoring their sensitivity to Treg-mediated suppression.
Star-Shaped and Linear POSS-Polylactide Hybrid Copolymers
Authors: Rozga-Wijas Krystyna , Stanczyk Wlodzimierz , Kurjata Jan , Kazmierski Slawomir
Published: July 2015

Novel octakis-2[(6-hydroxyhexyl)thio]ethyl-octasilsesquioxane (POSS-S-OH) as well as heptaisobutyl-2[(6-hydroxyhexyl)thio]ethyl-octasilsesquioxane (iBu-POSS-S-OH) were synthesized. POSS structures, bearing both types of groups i.e., 2[(6-hydroxyhexyl)thio]ethyl and the vinyl ones, pendant from the octahedral cage are also described. The synthetic pathway involved thiol-ene click reaction of 6-mercapto-1-hexanol (MCH) to octavinyloctasilsesquioxane (POSS-Vi), and heptaisobutylvinyloctasilsesquioxane (iBu-POSS-Vi), in the presence of 2,2′-azobisisobutyronitrile. The functionalized silsesquioxane cages of regular octahedral structure were used further as initiators for ring opening polymerization of L,L-dilactide, catalyzed by tin (II) 2-ethylhexanoate. The polymerization afforded biodegradable hybrid star shape and linear systems with an octasilsesquioxane cage as a core, bearing polylactide arm(s).
Low Molecular Weight Fucoidan Inhibits Tumor Angiogenesis through Downregulation of HIF-1/VEGF Signaling under Hypoxia
Authors: Chen Meng-Chuan , Hsu Wen-Lin , Hwang Pai-An , Chou Tz-Chong
Published: July 2015

Activation of hypoxia-induced hypoxia-inducible factors-1 (HIF-1) plays a critical role in promoting tumor angiogenesis, growth and metastasis. Low molecular weight fucoidan (LMWF) is prepared from brown algae, and exhibits anticancer activity. However, whether LMWF attenuates hypoxia-induced angiogenesis in bladder cancer cells and the molecular mechanisms involved remain unclear. This is the first study to demonstrate that LMWF can inhibit hypoxia-stimulated H2O2 formation, HIF-1 accumulation and transcriptional activity vascular endothelial growth factor (VEGF) secretion, and the migration and invasion in hypoxic human bladder cancer cells (T24) cells. LMWF also downregulated hypoxia-activated phosphorylation of PI3K/AKT/mTOR/p70S6K/4EBP-1 signaling in T24 cells. Blocking PI3K/AKT or mTOR activity strongly diminished hypoxia-induced HIF-1α expression and VEGF secretion in T24 cells, supporting the involvement of PI3K/AKT/mTOR in the induction of HIF-1α and VEGF. Additionally, LMWF significantly attenuated angiogenesis in vitro and in vivo evidenced by reduction of tube formation of hypoxic human umbilical vascular endothelial cells and blood capillary generation in the tumor. Similarly, administration of LMWF also inhibited the HIF-1α and VEGF expression in vivo, accompanied by a reduction of tumor growth. In summary, under hypoxia conditions, the antiangiogenic activity of LMWF in bladder cancer may be associated with suppressing HIF-1/VEGF-regulated signaling pathway.
Sumac Silver Novel Biodegradable Nano Composite for Bio-Medical Application: Antibacterial Activity
Authors: Ghorbani Parisa , Soltani Mozhgan , Homayouni-Tabrizi Masoud , Namvar Farideh , Azizi Susan , Mohammad Rosfarizan , Moghaddam Amin
Published: July 2015

The development of reliable and ecofriendly approaches for the production of nanomaterials is a significant aspect of nanotechnology nowadays. One of the most important methods, which shows enormous potential, is based on the green synthesis of nanoparticles using plant extract. In this paper, we aimed to develop a rapid, environmentally friendly process for the synthesis silver nanoparticles using aqueous extract of sumac. The bioactive compounds of sumac extract seem to play a role in the synthesis and capping of silver nanoparticles. Structural, morphological and optical properties of the nanoparticles were characterized using FTIR, XRD, FESEM and UV-Vis spectroscopy. The formation of Ag-NP was immediate within 10 min and confirmed with an absorbance band centered at 438 nm. The mean particle size for the green synthesized silver nanoparticles is 19.81 ± 3.67 nm and is fairly stable with a zeta potential value of −32.9 mV. The bio-formed Ag-NPs were effective against E. coli with a maximum inhibition zone of 14.3 ± 0.32 mm.
Phytochemical Properties and Anti-Proliferative Activity of Olea europaea L. Leaf Extracts against Pancreatic Cancer Cells
Authors: Goldsmith Chloe , Vuong Quan , Sadeqzadeh Elham , Stathopoulos Costas , Roach Paul , Scarlett Christopher
Published: July 2015

Olea europaea L. leaves are an agricultural waste product with a high concentration of phenolic compounds; especially oleuropein. Oleuropein has been shown to exhibit anti-proliferative activity against a number of cancer types. However, they have not been tested against pancreatic cancer, the fifth leading cause of cancer related death in Western countries. Therefore, water, 50% ethanol and 50% methanol extracts of Corregiola and Frantoio variety Olea europaea L. leaves were investigated for their total phenolic compounds, total flavonoids and oleuropein content, antioxidant capacity and anti-proliferative activity against MiaPaCa-2 pancreatic cancer cells. The extracts only had slight differences in their phytochemical properties, and at 100 and 200 μg/mL, all decreased the viability of the pancreatic cancer cells relative to controls. At 50 μg/mL, the water extract from the Corregiola leaves exhibited the highest anti-proliferative activity with the effect possibly due to early eluting HPLC peaks. For this reason, olive leaf extracts warrant further investigation into their potential anti-pancreatic cancer benefits.