bluuebunny/crossref_metadata_2025 huggingface dataset:
Economic impacts of forest pests: a case study of spruce budworm outbreaks and control in New Brunswick, Canada
Authors: Chang Wei-Yew , Lantz Van A. , Hennigar Chris R. , MacLean David A.
Published: March 2012

We investigated the potential economic impacts of future spruce budworm (SBW) ( Choristoneura fumiferana (Clemens)) outbreaks on 2.8 million hectares of Crown forest land in New Brunswick by coupling an advanced Spruce Budworm Decision Support System (SBW DSS) model with a dynamic computable general equilibrium model. A total of 16 alternative scenarios were evaluated, including two SBW outbreak severities (moderate versus severe), four SBW control program levels (protecting 0%, 10%, 20%, and 40% of susceptible Crown land forest area), and two pest management strategies (“without” versus “with” replanning harvest scheduling and salvage). The “without” replanning harvest scheduling and salvage strategy findings indicated that, under uncontrolled moderate and severe SBW outbreaks, total output in the New Brunswick economy over the 2012–2041 period would decline in present-value terms by CDN$3.3 billion and $4.7 billion, respectively. SBW control via aerial spraying was shown to reduce the negative impacts on output by up to 66% when protecting 40% of susceptible area. Combining SBW control with replanning harvest scheduling and salvage strategy under moderate and severe outbreaks would reduce the negative impacts on output by a further 1%–18% depending on the level of control implemented. These findings can help forest managers assess the direct and indirect economic effects of forest pest disturbances on regional economies and can also be used together with other sustainable forest management indicators to help broaden the scope of SBW and other forest pest management decision-making.
Niche contraction of American chestnut in response to chestnut blight
Authors: Burke Katie L.
Published: March 2012

Invasive pathogens can cause native population declines and change native species distributions, but the spatial limitations posed by disease are rarely explored. This study explored spatiotemporal variation in American chestnut ( Castanea dentata (Marsh.) Borkh.) survival over an 80-year period in response to the introduction of an invasive pathogen, chestnut blight ( Cryphonectria parasitica (Murrill) Barr), and identified changes in its current realized niche compared with its original niche. A study area in southwestern Virginia, USA, sampled historically for chestnut abundance before blight invasion, was resampled and measured for topography, soil chemistry, and forest composition. Pre-blight chestnut abundance was not significantly correlated to current chestnut abundance, suggesting that chestnut survival rate was not constant across stands. Results indicated that chestnut’s niche has shifted toward dry, high disturbance sites on southern- to western-facing slopes. This study provides evidence that chestnut is being constrained to a portion of its former niche following chestnut blight introduction because of spatial heterogeneity in survival rate.
Response of plant community abundance and diversity during 10 years of cattle exclusion within silvopasture systems
Authors: Lindgren Pontus M.F. , Sullivan Thomas P.
Published: March 2012

The effects of cattle ( Bos taurus L.) grazing on upland plant communities in forested rangelands are poorly understood. Cattle interactions with plant communities were studied in intensively managed (precommercially thinned (PCT) and repeatedly fertilized) silvopasture systems in young lodgepole pine ( Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) forests. We investigated the response of plant community abundance and diversity to cattle grazing and how these responses were affected by PCT and repeated fertilization. The study was conducted inside and outside cattle exclosures over 10 years in two regional replicates in south-central British Columbia, Canada. PCT and repeated fertilization increased both the amount and quality of forage. Effects of cattle grazing on plant community abundance and diversity were variable and significantly influenced by the nutrient status of the site. In fertilized stands, cattle grazing increased species richness and diversity, particularly for the herb layer, although these treatment effects often took several years to be expressed. In unfertilized stands, cattle grazing did not significantly reduce herb or shrub volumes; however, species richness and, to a lesser extent, diversity of the shrub layer declined. In a landscape context, management strategies for silvopasture should promote heterogeneity for conservation of plant diversity through a variety of grazing pressures, as well as forest enhancement treatments such as PCT and repeated fertilization.
Impacts of enhanced nitrogen deposition and soil acidification on biomass production and nitrogen leaching in Chinese fir plantations
Authors: Blanco Juan A. , Wei Xiaohua , Jiang Hong , Jie Cheng-Yue , Xin Zan-Hong
Published: March 2012

Atmospheric pollution levels in China are increasing quickly. Experience from other polluted regions shows that tree growth could be affected, but long-term effects of N deposition and soil acidification on Chinese forests remain mostly unknown. Soil acidification and N deposition were simulated for Chinese fir ( Cunninghamia lanceolata (Lamb.) Hook.) plantations managed for three consecutive 20-year rotations in southeastern China. A factorial experiment combined four rain pH levels (2.5, 4.0, 5.6, and 7.0), four N deposition rates (1, 7.5, 15, and 30 kg N·ha–1·year–1), and two site qualities (poor and rich). Results indicate that atmospheric pollution effects are not immediate, but after one to two rotations, soil acidification effects could reduce ecosystem C pools significantly (–25% and –11% in poor and rich sites, respectively). N deposition rates above 15 kg N·ha–1·year–1 could offset some of the negative effects of soil acidification and lead to more ecosystem C (19 and 28 Mg C·ha–1 more in poor and rich sites, respectively, than in low N deposition). However, at high N deposition rates (>15 kg N·ha–1·year–1), N leaching losses could greatly increase, reaching 75 kg N·ha–1·year–1. Moderate N deposition could increase tree biomass production and soil organic mass, resulting in increased ecosystem C, but these gains could be associated with important N leaching. Atmospheric pollution could also result in the long term in nutrient imbalances and additional ecological issues (i.e., biodiversity loss, eutrophication, etc.) not studied here.
Temporal variability of size–growth relationships in a Norway spruce forest: the influences of stand structure, logging, and climate
Authors: Castagneri Daniele , Nola Paola , Cherubini Paolo , Motta Renzo
Published: March 2012

In a forest stand, competition plays a central role, affecting individual growth. The size–growth relationship (SGR) indicates whether large trees grow proportionally more than (asymmetric SGR), equal to (symmetric), or less than (inversely asymmetric) smaller trees. SGR is thus an indicator of the growth partitioning and competition intensity within a stand. Using tree-ring analysis, we investigated long-term trends and interannual variability of SGR in several Norway spruce (Picea abies (L.) Karst.) stands in the Paneveggio Forest (eastern Italian Alps) over a 100-year period. The study plots were characterized by different stand structures (one multilayered and two monolayered) and disturbance histories (different dates of logging). Logging conducted until the 1940s induced an inversely asymmetric SGR in all the plots. During the successive five decades, in the monolayered plots, it shifted to direct asymmetric (plot 1) and to symmetric (plot 2). In the multilayered plot (plot 3), SGR remained inversely asymmetric. A direct effect of climate on SGR interannual variability was not found. However, fast-growing trees had a stronger climatic signal than slow-growing trees, indicating that growth rate affects tree response to climate. Moreover, we observed that sensitivity to climate was reduced in the monolayered plots over the study period, possibly as a consequence of increased competition.
Consistent negative temperature sensitivity and positive influence of precipitation on growth of floodplain Picea glauca in Interior Alaska
Authors: Juday Glenn Patrick , Alix Claire
Published: March 2012

This paper calibrates climate controls over radial growth of floodplain white spruce ( Picea glauca (Moench) Voss) and examines whether growth in these populations responds similarly to climate as upland trees in Interior Alaska. Floodplain white spruce trees hold previously unrecognized potential for long-term climate reconstruction because they are the source of driftwood that becomes frozen in coastal deposits, where archeological timbers and beach logs represent well-preserved datable material. We compared ring width chronologies for 135 trees in six stands on the Yukon Flats and Tanana River with temperature and precipitation at Fairbanks from 1912–2001. Our sample contains a stable common signal representing a strong negative relationship between summer temperature and tree growth. We developed a floodplain temperature index (FPTI), which explains half of the variability of the composite chronology, and a supplemental precipitation index (SPI) based on correlation of monthly precipitation with the residual of the temperature-based prediction of growth. We then combined FPTI and SPI into a climate favorability index (CFI) in which above-normal precipitation partially compensates for temperature-induced drought reduction of growth and vice versa. CFI and growth have been particularly low since 1969. Our results provide a basis for building longer chronologies based on archeological wood and for projecting future growth.
Woody biomass availability for bioenergy production using forest depletion spatial data in northwestern Ontario
Authors: Alam Md. Bedarul , Pulkki Reino , Shahi Chander
Published: March 2012

Woody biomass contributes about 6% of total energy production in Canada. One obstacle to the adoption of woody biomass for energy production is accurate data on sustainable supply. The purpose of this study is to demonstrate the assessment of woody biomass annually available for bioenergy production. The study area, located in northwestern Ontario, includes 18 forest management units (167 184 km2) and three existing and one proposed biomass-based power generating stations, with a potential annual demand of 2.2 million green tonnes (gt). First, pre- and post-harvest inventories were carried out to assess the availability of harvest residues. Second, two spatial database layers (land-use class and forest depletion) were developed. The pre- and post-harvest inventory data were combined with spatial data analysis to estimate woody biomass in each square kilometre of the study area. It was estimated that annually there was more than 2.1 million gt of forest harvest residue and 7.6 million gt of underutilized woody biomass technically available between 2002 and 2009 for bioenergy production, with an average annual forest depletion rate of 60 867 ha, 0.6% of the total productive forest area. The study provides a tool for assessing the sustainable availability of woody biomass feedstock for power generation.
Drought signals inferred from ring-width and stable carbon isotope chronologies fromThuja occidentalistrees growing at their northwestern distribution limit, central Canada
Authors: Au Robert , Tardif Jacques C.
Published: March 2012

Stable carbon isotopes (δ13C) fixed in tree rings are dependent upon environmental conditions. Old northern white-cedar ( Thuja occidentalis L.) trees were sampled at their northwestern limit of distribution in central Canada. The objectives of the study were (i) to investigate the association between tree-ring δ13C values and radial growth in addition to the response of these variables to climate, (ii) to assess site differences between two sites varying in moisture regime, and (iii) to compare tree-ring δ13C of T. occidentalis with that of other boreal tree species growing at the northern limit of their distribution in central Canada. Over 2500 tree rings comprised of 15 T. occidentalis trees were analyzed for δ13C. Annually resolved δ13C (1650–2006) and ring-width (1542–2006) chronologies were developed. During the year of ring formation, ring width was associated with spring and early-summer conditions, whereas δ13C was more indicative of overall summer conditions. However, compared with δ13C values, ring width was more often associated with climate conditions in the year prior to ring formation. Conditions conducive to moisture stress were important for both parameters. Although ring width and δ13C corresponded to the drought intervals of the 1790s, 1840s, 1890s, 1930s, and 1960–1970, ring width may be more responsive to prolonged drought than δ13C. Tree-ring δ13C could, however, provide important information regarding physiological adaptations to drought.
Do changes in soil properties after rooting by wild boars (Sus scrofa) affect understory vegetation in Swiss hardwood forests?
Authors: Wirthner Sven , Schütz Martin , Page-Dumroese Deborah S. , Busse Matt D. , Kirchner James W. , Risch Anita C.
Published: March 2012

Recovering from small fragmented populations, wild boars ( Sus scrofa L.) have considerably increased their numbers and their habitat range in many European countries during the past two decades. Although several studies have focused on the impact of wild boar rooting on selected vegetation properties, little is known about effects on entire forest ecosystems. The main goal of our study was to assess how rooting by boars alters soil and vegetation properties. We measured soil chemical and biological properties (C and N concentrations, N availability, and microbial biomass C) as well as several vegetation characteristics (total plant cover, plant species diversity, and number and height of saplings) on paired rooted and non-rooted plots in six hardwood forests in Switzerland. We found that rooting by wild boars led to significant increases in mineral soil C and N concentrations and microbial biomass C, which could lead to improved growth conditions for plants. However, total plant cover and sapling counts were reduced on rooted plots, possibly due to mechanical disturbance or due to reduced plant available N (measured as supply rate in contrast with the observed increase in total stocks of mineral soil N). In view of these results, simple characterizations of wild boar rooting as beneficial or detrimental to forest ecosystems should be handled with care.
USE OF CRYSTALS FOR BEAM DEFLECTION IN PARTICLE ACCELERATORS
Authors: SCANDALE WALTER
Published: February 2012

Charged particles interacting with a bent crystal can be trapped in channeling states and deflected by the atomic planes of the crystal lattice. The use of bent crystals for beam manipulation in particle accelerators is a well assessed concept rapidly evolving into practical applications. In the last three decades, a large number of experimental findings have contributed to clarify our knowledge and to improve our control of crystal–particle interactions. Bent crystals can impart angular deflections to the incoming particles, through channeling or volume reflection mechanisms. The efficiency of the latter mechanism has been found to be intrinsically very large, whilst the channeling efficiency has been improved by the increased technological expertize in crystal cutting and bending. In this paper, we review the recent milestones of the worldwide effort to propose a routine use of bent crystals in particle accelerators, with a specific attention to the proposals of promoting the use of bent crystals as primary element in beam halo collimation systems.
ON GEOMETRIC RELATIVISTIC FOUNDATIONS OF MATTER FIELD EQUATIONS AND PLANE WAVE SOLUTIONS
Authors: FABBRI LUCA
Published: February 2012

In this paper, we start from the geometric relativistic foundations to define the basis upon which matter field theories are built, and their wave solutions are investigated, finding that they display repulsive interactions able to reproduce the exclusion principle in terms of its effects in a dynamical way, then discussing possible consequences and problems.
The petroleum potential of the Riphean-Vendian succession of southern East Siberia
Authors: Howard James P. , Bogolepova Olga K. , Gubanov Alexander P. , Gόmez-Pérez Marcela
Published: March 2012

The Siberian Platform covers an area of
c.
4.5 million km
2
in the East Siberia region of Russia, up to 3.5 million km
2
of which is prospective for hydrocarbons. We review the Archaean to Neoproterozoic evolution of the Siberian Platform and the potential oil and gas resources of Riphean, Vendian and Infracambrian sediments. The Riphean was dominated by passive margin sedimentation and was intensely deformed during the Baikalian orogeny. Vendian strata record a clastic transgressive sequence and the eventual re-establishment of carbonate platform sedimentation. The late Vendian–early Cambrian is characterized by carbonate deposition including thick salt horizons, which form a regional seal. Hydrocarbon maturation and migration from Riphean and Vendian source rocks occurred during the late Neoproterozoic and Early Palaeozoic, indicating that hydrocarbon reservoirs on the Siberian Platform may have hosted their reserves over a remarkable period of geological time. Despite many years of hydrocarbon exploration in East Siberia, many regions remain under-explored, and aspects of the proven hydrocarbon systems are poorly understood. There are undoubtedly more major discoveries to be made in the region, and the Infracambrian succession of the southern Siberian Platform therefore represents an irresistible target for further hydrocarbon exploration.
Neoproterozoic Blaini glacial diamictite and Ediacaran Krol carbonate sedimentation in the Lesser Himalaya, India
Authors: Tewari Vinod C.
Published: March 2012

The breakup of Rodinia resulted in the formation of rift basins and passive margins
c.
650 Ma. Major palaeoclimatic vents such as Neoproterozoic global glaciation (known as ‘snowball Earth’;

Hoffman
et al.
1998

) followed by global warming have been recorded on different continents, including the Indian Lesser Himalaya (Blaini–Krol Cryogenian–Ediacaran Period). The reconstruction of the Rodinia supercontinent (

Powell
et al.
1993

;

Li
et al.
2003

) and the palaeoposition of India (including Lesser Himalaya–Southern China shelf facies,
Tewari 2010
) strongly suggest that a connection of the Lesser Himalayan Neoproterozoic sedimentary basins with Rodinia must have existed. Early Earth possibly witnessed its most extreme climatic fluctuations during the mid late Neoproterozoic between 750 and 550 Ma. Palaeoglaciers even reached the equator
c.
635 Ma, covering the whole Earth. Evidence from Australia, Africa, Antarctica, South America, South China and the Indian Lesser Himalaya suggest that there may have been three or more palaeoglacial events during this 200 million year interval. The global decline of Meso-Neoproterozoic stromatolites, biotic evolution, diversification, extinctions and the discovery of Ediacaran life following the cold climate are of great significance. Carbon isotopic excursions from all pink cap carbonates from the Lesser Himalaya capping the Blaini glacial diamictites have shown strong negative excursions, whereas the overlying Ediacaran Krol carbonates are characterized by a positive shift in carbon isotope ratios (
Tewari 2010
). In the Lesser Himalayan Krol belt, extending from the Solan in Himachal to Nainital in Uttarakhand Lesser Himalaya, the Upper Krol Formation (Krol D Member,
Auden, 1934
,
1937
) is a typical Ediacaran (terminal Neoproterozoic) microbial carbonate sedimentation facies. Krol D contains Ediacaran metazoan fossils and abundant microbial structures in the form of columnar, domal and stratified stromatolites. Peloids, oncoids and microphytolites are also microbially formed structures. Carbonate grainstones and packstones are common in Krol D, and the allochemical constituents are intraclasts, ooids, coated grains, peloids, microbial grains and catagraphs. A diagenesis and cathodoluminescence study of the Krol ooids has been done in detail for the first time. The sedimentary structures present in the non-stromatolitic Krol carbonates include bird's eye, cross beddings, symmetrical ripples and shallow channel structures. An intertidal to supratidal carbonate ramp depositional environment with some moderate currents and intermittent periods of exposure has been suggested for the Upper Krol carbonates of the Lesser Himalaya. A moderate to high content of organic matter (kerogen) in the Neoproterozoic microbial fossils indicates the presence of probable hydrocarbon source rocks.
Neoproterozoic successions in Peninsular India and their hydrocarbon prospectivity
Authors: Ram Jokhan
Published: March 2012

The burgeoning oil and gas consumption in India in recent years has necessitated looking into the Proterozoic basins of India, which are sparsely explored and have a scanty knowledge base. The rationale for hydrocarbon exploration in Indian Proterozoic basins is derived from the fact that they have large basinal areas, wide geographical distribution, varied geotectonic setting and sedimentary fill. The favourable tectonic settings of these basins, pronounced biological activity, known hydrocarbon gas seepages, and subsurface commercially viable oil and gas shows in the Bikaner–Nagaur and Vindhyan basins and analogous basins throughout the world necessitate proactive exploration strategies in these basins. The basins of Bikaner–Nagaur, Vindhyan, Cuddapah and Chhatishgarh include thick Neoproterozoic/basal Lower Palaeozoic (Cambrian) successions, in addition to Palaeoproterozoic and Mesoproterozoic sequences. The Neoproterozic sediments in these basins incorporate thick successions of shale, limestone and sandstone. These successions have rich organic matter of high-quality cyanophycean (stromatolites, acritarchs and filamentous algae) affinity that is proven to be high-quality (type one) source material for hydrocarbon generation and also involved in later structurization. However, the Neoproterozoic sedimentary pack in the Bhima–Kaladgi basins is comparatively less thick, and appears to have less prospectivity. The available geological and source-rock data are reassessed for their hydrocarbon prospectivity in order to help in planning a strategy for exploration in these basins.
Analytical essay writing: a new activity introduced to a traditional curriculum
Authors: Kommalage Mahinda
Published: March 2012

Medical students following a traditional curriculum get few opportunities to engage in activities such as a literature search, scientific writing, and active and collaborative learning. An analytical essay writing activity (AEWA) in physiology was introduced to first-year students. Each student prepared an essay incorporating new research findings with existing knowledge on a medical topic. Students were expected to study on the topic in detail from textbooks as well as from research publications and write a descriptive and critical analysis. This activity would help them to be aware of new developments in the field and understand the complexity and rapidity of changes in the subject. The aim of this study was to learn how students used the AEWA as a learning process. For this purpose, student perceptions were assessed quantitatively and those of the faculty staff were assessed qualitatively. The data from the students showed considerable achievements in the medical database search, scientific writing, group work, and search for new scientific knowledge. The activity was influenced by prior capabilities in computer use, English language knowledge, and writing ability. Resources available at the medical school had a greater influence on the activity. Faculty staff appreciated the quality of the essay while highlighting areas of improvement. The students seemed to be satisfied with the supervisory role of the faculty staff, whereas the staff felt that the students used the supervisors less than expected. The AEWA was a successful activity promoting many aspects of active and collaborative learning. The low availability of books and information and communications technology (ICT) resources, poor internet connection, and insufficient English language skills were probably responsible for the negative feedback on this activity in this resource-deprived environment.
A laboratory exercise using a physical model for demonstrating countercurrent heat exchange
Authors: Loudon Catherine , Davis-Berg Elizabeth C. , Botz Jason T.
Published: March 2012

A physical model was used in a laboratory exercise to teach students about countercurrent exchange mechanisms. Countercurrent exchange is the transport of heat or chemicals between fluids moving in opposite directions separated by a permeable barrier (such as blood within adjacent blood vessels flowing in opposite directions). Greater exchange of heat or chemicals between the fluids occurs when the flows are in opposite directions (countercurrent) than in the same direction (concurrent). When a vessel loops back on itself, countercurrent exchange can occur between the two arms of the loop, minimizing loss or uptake at the bend of the loop. Comprehension of the physical principles underlying countercurrent exchange helps students to understand how kidneys work and how modifications of a circulatory system can influence the movement of heat or chemicals to promote or minimize exchange and reinforces the concept that heat and chemicals move down their temperature or concentration gradients, respectively. One example of a well-documented countercurrent exchanger is the close arrangement of veins and arteries inside bird legs; therefore, the setup was arranged to mimic blood vessels inside a bird leg, using water flowing inside tubing as a physical proxy for blood flow within blood vessels.
Continuous and noninvasive recording of cardiovascular parameters with the Finapres finger cuff enhances undergraduate student understanding of physiology
Authors: Hodgson Yvonne , Choate Julia
Published: March 2012

The Finapres finger cuff recording system provides continuous calculations of beat-to-beat variations in cardiac output (CO), total peripheral resistance, heart rate (HR), and blood pressure (BP). This system is unique in that it allows experimental subjects to immediately, continuously, and noninvasively visualize changes in CO at rest and during exercise. This study provides evidence that using the Finapres system improves undergraduate student engagement, understanding, and learning of how the cardiovascular system responds to exercise. Second-year science students undertaking a physiology practical class in 2009 ( n = 243) and 2010 ( n = 263) used the Finapres system to record CO, BP, and HR during graded exercise on a cycle ergometer. Student experiences with the Finapres was evaluated with a survey (a 5-point scale from strongly disagree to strongly agree). This indicated that students appreciated the immediacy of the recordings (88% of students agreed or strongly agreed, average for 2009 and 2010), gained an understanding of how to record physiological data (84%), enjoyed the practical (81%), and would recommend the Finapres to other students (81%). To determine if the practical enhanced student learning of cardiovascular physiology, identical tests were given to the students at the beginning (pretest) and end (posttest) of the class. There was a significant improvement from the pretest to the posttest (4% in 2009 and 20% in 2010). In summary, the ability of the Finapres to continuously display CO, BP, and HR during experimental protocols provides students with immediate feedback and improves their understanding of cardiovascular physiology.
Effects of different forms of physiology instruction on the development of students' conceptions of and approaches to science learning
Authors: Lin Yi-Hui , Liang Jyh-Chong , Tsai Chin-Chung
Published: March 2012

The purpose of this study was to investigate students' conceptions of and approaches to learning science in two different forms: internet-assisted instruction and traditional (face-to-face only) instruction. The participants who took part in the study were 79 college students enrolled in a physiology class in north Taiwan. In all, 46 of the participants were from one class and 33 were from another class. Using a quasi-experimental research approach, the class of 46 students was assigned to be the “internet-assisted instruction group,” whereas the class of 33 students was assigned to be the “traditional instruction group.” The treatment consisted of a series of online inquiry activities. To explore the effects of different forms of instruction on students' conceptions of and approaches to learning science, two questionnaires were administered before and after the instruction: the Conceptions of Learning Science Questionnaire and the Approaches to Learning Science Questionnaire. Analysis of covariance results revealed that the students in the internet-assisted instruction group showed less agreement than the traditional instruction group in the less advanced conceptions of learning science (such as learning as memorizing and testing). In addition, the internet-assisted instruction group displayed significantly more agreement than the traditional instruction group in more sophisticated conceptions (such as learning as seeing in a new way). Moreover, the internet-assisted instruction group expressed more orientation toward the approaches of deep motive and deep strategy than the traditional instruction group. However, the students in the internet-assisted instruction group also showed more surface motive than the traditional instruction group did.
Emergency contraception and RU-486 (mifepristone): do bioethical discussions improve learning and retention?
Authors: Bodensteiner Karin J.
Published: March 2012

To systematically investigate whether the inclusion of a bioethical discussion improves the learning and retention of biological content, students in two sections of an introductory zoology class were taught the biology behind emergency contraception and RU-486. Students in one section of the course participated in a bioethical discussion, whereas students in the other section participated in a content-only discussion. Pre- and postsurveys, response paragraphs, and a final exam were collected and used to examine the learning and retention of content knowledge. Results suggested that students who participated in a bioethical discussion of emergency contraception and RU-486 learned and retained information better than students who received content-only instruction. Interestingly, students who participated in the bioethical discussion also appeared to be more confident in their answers. The results of this study may inform the teaching practices and goals of science educators who would like to incorporate a discussion of bioethical issues into their curriculum but often feel that content coverage is paramount.
Internet-based course on pulmonary pathophysiology
Authors: West John B.
Published: March 2012

A course of seven video lectures on pulmonary pathophysiology has been placed on the internet. This is a companion to the course on respiratory physiology available at http://meded.ucsd.edu/ifp/jwest/ . That course dealt with normal respiratory physiology, and the new lectures are about the function of the diseased lung. The topics covered include pulmonary function tests, chronic obstructive pulmonary disease, asthma and localized airway obstruction, restrictive lung diseases, pulmonary vascular diseases, environmental or industrial lung diseases (with a short section on neoplastic and infectious diseases), and respiratory failure. Although it could be argued that PhD physiologists do not have a responsibility for teaching pathophysiology, collaborative teaching has become increasingly common in medical schools where, for example, a pulmonary block includes both normal respiratory physiology and some pulmonary pathophysiology. It is hoped that these lectures will be useful to physiologists in that setting.
Determinants of evolving metabolic and cardiovascular benefit/risk profiles of rosiglitazone therapy during the natural history of diabetes: molecular mechanisms in the context of integrated pathophysiology
Authors: Sgarra Luca , Addabbo Francesco , Potenza Maria Assunta , Montagnani Monica
Published: February 2012

Rosiglitazone is a thiazolidinedione, a synthetic PPARγ receptor agonist with insulin-sensitizing properties that is used as an antidiabetic drug. In addition to improving glycemic control through actions in metabolic target tissues, rosiglitazone has numerous biological actions that impact on cardiovascular homeostasis. Some of these actions are helpful (e.g., improving endothelial function), whereas others are potentially harmful (e.g., promoting fluid retention). Since cardiovascular morbidity and mortality are major endpoints for diabetes, it is essential to understand how the natural history of diabetes alters the net benefits and risks of rosiglitazone therapy. This complex issue is an important determinant of optimal use of rosiglitazone and is critical for understanding cardiovascular safety issues. We give special attention to the effects of rosiglitazone in diabetic patients with stable coronary artery disease and the impact of rosiglitazone actions on atherosclerosis and plaque instability. This provides a rational conceptual framework for predicting evolving benefit/risk profiles that inform optimal use of rosiglitazone in the clinical setting and help explain the results of recent large clinical intervention trials where rosiglitazone had disappointing cardiovascular outcomes. Thus, in this perspective, we describe what is known about the molecular mechanisms of action of rosiglitazone on cardiovascular targets in the context of the evolving pathophysiology of diabetes over its natural history.
Reducing Excessive Amounts of Data: Multiple Web Queries for Generation of Pun Candidates
Authors: Dybala Pawel , Ptaszynski Michal , Sayama Kohichi
Published: February 2012

Humor processing is still a less studied issue, both in NLP and AI. In this paper we contribute to this field. In our previous research we showed that adding a simple pun generator to a chatterbot can significantly improve its performance. The pun generator we used generated only puns based on words (not phrases). In this paper we introduce the next stage of the system's development—an algorithm allowing generation of phrasal pun candidates. We show that by using only the Internet (without any hand-made humor-oriented lexicons), it is possible to generate puns based on complex phrases. As the output list is often excessively long, we also propose a method for reducing the number of candidates by comparing two web-query-based rankings. The evaluation experiment showed that the system achieved an accuracy of 72.5% for finding proper candidates in general, and the reduction method allowed us to significantly shorten the candidates list. The parameters of the reduction algorithm are variable, so that the balance between the number of candidates and the quality of output can be manipulated according to needs.
In Vitro Assessment of Antibacterial Activity and Cytocompatibility of Quercetin‐Containing PLGA Nanofibrous Scaffolds for Tissue Engineering
Authors: Xing Zhi-Cai , Meng Wan , Yuan Jiang , Moon Sungmo , Jeong Yongsoo , Kang Inn-Kyu
Published: March 2012

Flavonoids, such as quercetin, have been reported to exhibit a wide range of biological activities related to their antioxidant capacity. The aim of this study was to investigate the protective effect of quercetin on cell adhesion, and the viability and proliferation of KB epithelial cells. Quercetin‐ (1, 5 wt%)‐containing poly (l‐lactide‐co‐glycolide) (PLGA) nanofibrous scaffolds (PLGA/Q 1, PLGA/Q 5) were prepared by electrospinning technique and their antibacterial properties were examined. Two types of bacteria strains, Staphylococcus aureus (SA) and Klebsiella pneumoniae (KP), were used to evaluate the antibacterial properties of the scaffolds. The results showed that the quercetin‐containing PLGA nanofibrous scaffolds exhibited significant antibacterial effects against the two bacterial strains. KB epithelial cells were also used to evaluate the cytocompatibility of the scaffolds. From the results, it was found that the PLGA nanofibrous scaffolds with 1 wt% of quercetin had good cell compatibility. It is considered that the PLGA nanofibrous scaffolds with 1 wt% quercetin have potential to be used in tissue engineering.
Constructing an Urban Population Model for Medical Insurance Scheme Using Microsimulation Techniques
Authors: Xiong Linping , Zhang Lulu , Tang Weidong , Ma Yuqin
Published: March 2012

China launched a pilot project of medical insurance reform in 79 cities in 2007 to cover urban nonworking residents. An urban population model was created in this paper for China’s medical insurance scheme using microsimulation model techniques. The model made it clear for the policy makers the population distributions of different groups of people, the potential urban residents entering the medical insurance scheme. The income trends of units of individuals and families were also obtained. These factors are essential in making the challenging policy decisions when considering to balance the long-term financial sustainability of the medical insurance scheme.
Cusp Forms in and the Number of Representations of Positive Integers by Some Direct Sum of Binary Quadratic Forms with Discriminant
Authors: Kendirli Barış
Published: March 2012

A basis of is given and the formulas for the number of representations of positive integers by some direct sum of the quadratic forms , , are determined.
Use of Recombination-Mediated Genetic Engineering for Construction of Rescue Human Cytomegalovirus Bacterial Artificial Chromosome Clones
Authors: Dulal Kalpana , Silver Benjamin , Zhu Hua
Published: March 2012

Bacterial artificial chromosome (BAC) technology has contributed immensely to manipulation of larger genomes in many organisms including large DNA viruses like human cytomegalovirus (HCMV). The HCMV BAC clone propagated and maintained insideE. coliallows for accurate recombinant virus generation. Using this system, we have generated a panel of HCMV deletion mutants and their rescue clones. In this paper, we describe the construction of HCMV BAC mutants using a homologous recombination system. A gene capture method, or gap repair cloning, to seize large fragments of DNA from the virus BAC in order to generate rescue viruses, is described in detail. Construction of rescue clones using gap repair cloning is highly efficient and provides a novel use of the homologous recombination-based method inE. colifor molecular cloning, known colloquially as recombineering, when rescuing large BAC deletions. This method of excising large fragments of DNA provides important prospects forin vitrohomologous recombination for genetic cloning.
Unraveling the Determinants of Protrusion Formation
Authors: Varghese Mita , Gorsevski Peter , Cayer Marilyn L. , Boudreau Nancy S. , Heckman Carol A.
Published: March 2012

A computerized morphometric classification technique based on latent factors reveals major protrusion classes: factors 4, 5, and 7. Previous work showed that factor 4 represented filopodia, 5 the distribution of lamellar cytoplasm, and 7 a blunt protrusion. We explore the relationship of focal contact (FC) characteristics and their integrated actin cables to factors values. The results show that FC maturation/cytoskeletal integration affects factor 5, because FC elongation/integration was correlated with its values. On the contrary, 7 values decreased with maturation, so cable or FC size or their integration must be restricted to form these protrusions. Where integration did occur, the cables showed distinctive size and orientation, as indicated by correlation of 7 values with FC shape. Results obtained with myosin inhibitors support the interpretation that a central, isometric, contractile network puts constraints on both factor 5 and 7 protrusions. We conclude that cells establish functional domains by rearranging the cytoskeleton.
A Class of Integral Operators and Bessel Plancherel Transform on
Authors: Dziri M.
Published: March 2012

For the relation between Bessel Plancherel transform and a wide class of integral operators we establish some results generalizing the corresponding results for the cosine transform, given by Goldberg (1972) and Titchmarsh (1937). Building on these results we obtain a new properties of certain well-known integral transforms associated with the eigenfunction of the Bessel differential operator defined on (0, ∞) by , . We also construct a class of integral operators which commute with Bessel Plancherel transform.
Inflammation as a Link between Obesity and Metabolic Syndrome
Authors: Emanuela Faloia , Grazia Michetti , Marco De Robertis , Maria Paola Luconi , Giorgio Furlani , Marco Boscaro
Published: March 2012

The metabolic syndrome is a complex of clinical features leading to an increased risk for cardiovascular disease and type 2 diabetes mellitus in both sexes. Visceral obesity and insulin resistance are considered the main features determining the negative cardiovascular profile in metabolic syndrome. The aim of this paper is to highlight the central role of obesity in the development of a chronic low-grade inflammatory state that leads to insulin resistance, endothelial and microvascular dysfunctions. It is thought that the starting signal of this inflammation is overfeeding and the pathway origins in all the metabolic cells; the subsequent increase in cytokine production recruits immune cells in the extracellular environment inducing an overall systemic inflammation. This paper focuses on the molecular and cellular inflammatory mechanisms studied until now.
General Computational Model for Human Musculoskeletal System of Spine
Authors: Kim Kyungsoo , Kim Yoon Hyuk , Lee SuKyoung
Published: March 2012

A general computational model of the human lumbar spine and trunk muscles including optimization formulations was provided. For a given condition, the trunk muscle forces could be predicted considering the human physiology including the follower load concept. The feasibility of the solution could be indirectly validated by comparing the compressive force, the shear force, and the joint moment. The presented general computational model and optimization technology can be fundamental tools to understand the control principle of human trunk muscles.
Altered Neurochemical Ingredient of Hippocampus in Patients with Bipolar Depression
Authors: Atmaca Murad , Yildirim Hanefi
Published: March 2012

Background. In a number of investigations, hippocampal neurochemicals were evaluated in the patients with bipolar disorder who were on their first episode or euthymic periods. However, we did not meet any investigation in which only patients with bipolar depression were examined. As a consequence, the objective of the present study was to examine both sides of hippocampus of patients with bipolar disorder in depressive episode and healthy controls using1H-MRS.Methods. Thirteen patients with DSM-IV bipolar I disorder, most recent episode depressed, were recruited from the Department of Psychiatry at Firat University School of Medicine. We also studied 13 healthy comparison subjects who were without any DSM-IV Axis I disorders recruited from the hospital staff. The patients and controls underwent proton magnetic resonance spectroscopy (1H-MRS) of their hippocampus. NAA, CHO, and CRE values were measured.Results. No significant effect of diagnosis was observed for NAA/CRE ratio. For the NAA/CHO ratio, the ANCOVA with age, gender, and whole brain volume as covariates revealed that the patients with bipolar depression had significantly lower ratio compared to healthy control subjects for right and for left side. As for the CHO/CRE ratio, the difference was statistically significant for right side, with an effect diagnosis ofF= 4.763,P= 0.038, and was very nearly significant for left side, with an effect diagnosis ofF= 3.732,P= 0.064.Conclusions. We found that the patients with bipolar depression had lower NAA/CHO and higher CHO/CRE ratios compared to those of healthy control subjects. The findings of the present study also suggest that there may be a degenerative process concerning the hippocampus morphology in the patients with bipolar depression.
Dairy Biomass-Wyoming Coal Blends Fixed Gasification Using Air-Steam for Partial Oxidation
Authors: Gordillo Gerardo , Annamalai Kalyan
Published: February 2012

Concentrated animal feeding operations such as dairies produce a large amount of manure, termed as dairy biomass (DB), which could serve as renewable feedstock for thermal gasification. DB is a low-quality fuel compared to fossil fuels, and hence the product gases have lower heat content; however, the quality of gases can be improved by blending with coals. This paper deals with air-steam fixed-bed counterflow gasification of dairy biomass-Wyoming coal blend (DBWC). The effects of equivalence ratio (1.6<Φ<6.4) and steam-to-fuel ratio (0.4<S:F<0.8) on peak temperatures, gas composition, gross heating value of the products, and energy recovery are presented. According to experimental results, increasing Φ and (S:F) ratios decreases the peak temperature and increases the H2and CO2production, while CO production decreases. On the other hand, the concentrations of CH4and C2H6were lower compared to those of other gases and almost not affected by Φ.
Connexins and Diabetes
Authors: Wright Josephine A. , Richards Toby , Becker David L.
Published: March 2012

Cell-to-cell interactions via gap junctional communication and connexon hemichannels are involved in the pathogenesis of diabetes. Gap junctions are highly specialized transmembrane structures that are formed by connexon hemichannels, which are further assembled from proteins called “connexins.” In this paper, we discuss current knowledge about connexins in diabetes. We also discuss mechanisms of connexin influence and the role of individual connexins in various tissues and how these are affected in diabetes. Connexins may be a future target by both genetic and pharmacological approaches to develop treatments for the treatment of diabetes and its complications.
Automated VOI Analysis in FDDNP PET Using Structural Warping: Validation through Classification of Alzheimer's Disease Patients
Authors: Wilks Moses Q. , Protas Hillary , Wardak Mirwais , Kepe Vladimir , Small Gary W. , Barrio Jorge R. , Huang Sung-Cheng
Published: March 2012

We evaluate an automated approach to the cortical surface mapping (CSM) method of VOI analysis in PET. Although CSM has been previously shown to be successful, the process can be long and tedious. Here, we present an approach that removes these difficulties through the use of 3D image warping to a common space. We test this automated method using studies of FDDNP PET in Alzheimer's disease and mild cognitive impairment. For each subject, VOIs were created, through CSM, to extract regional PET data. After warping to the common space, a single set of CSM-generated VOIs was used to extract PET data from all subjects. The data extracted using a single set of VOIs outperformed the manual approach in classifying AD patients from MCIs and controls. This suggests that this automated method can remove variance in measurements of PET data and can facilitate accurate, high-throughput image analysis.
Iterative Algorithms for Solving the System of Mixed Equilibrium Problems, Fixed‐Point Problems, and Variational Inclusions with Application to Minimization Problem
Authors: Chamnarnpan Tanom , Kumam Poom
Published: March 2012

We introduce a new iterative algorithm for solving a common solution of the set of solutions of fixed point for an infinite family of nonexpansive mappings, the set of solution of a system of mixed equilibrium problems, and the set of solutions of the variational inclusion for a β‐inverse‐strongly monotone mapping in a real Hilbert space. We prove that the sequence converges strongly to a common element of the above three sets under some mild conditions. Furthermore, we give a numerical example which supports our main theorem in the last part.