bluuebunny/crossref_metadata_2025 huggingface dataset:
Race and Colon Cancer Survival in an Equal-Access Health Care System
Authors: Andaya Abegail A. , Enewold Lindsey , Zahm Shelia H. , Shriver Craig D. , Stojadinovic Alexander , McGlynn Katherine A. , Zhu Kangmin
Published: April 2013

Studies have shown that Whites have a higher colorectal cancer survival rate than Blacks. However, it is unclear whether racial disparities result from unequal access to medical care or factors other than health care access or both. This study assessed whether non-Hispanic Whites (NHW) and non-Hispanic Blacks (NHB) differ in colon cancer survival in an equal-access health care system and examined whether racial differences varied by demographic and tumor characteristics. The study included 2,537 Military Health System patients diagnosed with colon cancer between 1998 and 2007. Median follow-up time was 31.4 months. Cox models estimated HRs and 95% confidence intervals (CI) for race, overall and stratified by age at diagnosis, sex, and tumor stage. No difference in overall survival (OS) between NHWs and NHBs was observed in general. However, among patients younger than 50 years old, NHBs experienced significantly worse OS than NHWs (HR: 2.03, 95% CI: 1.30–3.19). Furthermore, stratification by sex and tumor stage showed that this racial disparity was confined to women (HR: 2.87; 95% CI: 1.35–6.11) and patients with distant stage disease (HR: 2.45; 95% CI: 1.15–5.22) in this age group. When medical care is equally available to NHWs and NHBs, similar overall colon cancer survival was observed; however, evidence of racial differences in survival was apparent for patients younger than 50 years old. This study suggests that factors other than access to care may be related to racial disparities in colon cancer survival among younger, but not older, patients. Cancer Epidemiol Biomarkers Prev; 22(6); 1030–6. ©2013 AACR.
Colorectal Cancer: Looking for Answers in the Microbiota
Authors: Jobin Christian
Published: April 2013

Summary: At a simplistic level, colorectal cancer arises from mutations in various proto-oncogenes and tumor suppressor genes. Aside from genetically inherited factors, environmental, lifestyle, and dietary habits have all been identified as risk agents promoting mutational events leading to the development of colorectal cancer. This “In Focus” presents evidence that the intestinal endogenous bacterial community represents a risk factor for the development of colorectal cancer. Cancer Discov; 3(4); 384–7. ©2013 AACR.
Incorporating Prior Biologic Information for High-Dimensional Rare Variant Association Studies
Authors: Quintana Melanie A. , Schumacher Fredrick R. , Casey Graham , Bernstein Jonine L. , Li Li , Conti David V.
Published: April 2013

Background: Given the increasing scale of rare variant association studies, we introduce a method for high-dimensional studies that integrates multiple sources of data as well as allows for multiple region-specific risk indices. Methods: Our method builds upon the previous Bayesian risk index by integrating external biological variant-specific covariates to help guide the selection of associated variants and regions. Our extension also incorporates a second level of uncertainty as to which regions are associated with the outcome of interest. Results: Using a set of study-based simulations, we show that our approach leads to an increase in power to detect true associations in comparison to several commonly used alternatives. Additionally, the method provides multi-level inference at the pathway, region and variant levels. Conclusion: To demonstrate the flexibility of the method to incorporate various types of information and the applicability to high-dimensional data, we apply our method to a single region within a candidate gene study of second primary breast cancer and to multiple regions within a candidate pathway study of colon cancer.
Rare Variants in Complex Traits: Novel Identification Strategies and the Role of de novo Mutations
Authors: Jouan Loubna , Gauthier Julie , Dion Patrick A. , Rouleau Guy A.
Published: April 2013

Following the limited success of linkage and association studies aimed at identifying the genetic causes of common neurodevelopmental syndromes like autism and schizophrenia, complex traits such as these have recently been considered under the ‘common disease-rare variant' hypothesis. Prior to this hypothesis, the study of candidate genes has enabled the discovery of rare variants in complex disorders, and in turn some of these variants have highlighted the genetic contribution of de novo variants. De novo variants belong to a subcategory of spontaneous rare variants that are largely associated with sporadic diseases, which include some complex psychiatric disorders where the affected individuals do not transmit the genetic defects they carry because of their reduced reproductive fitness. Interestingly, recent studies have demonstrated the rate of germline de novo mutations to be higher in individuals with complex psychiatric disorders by comparison to what is seen in unaffected control individuals; moreover, de novo mutations carried by affected individuals have generally been more deleterious than those observed in control individuals. Advanced sequencing technologies have recently enabled the undertaking of massive parallel sequencing projects that can cover the entire coding sequences (exome) or genome of several individuals at once. Such advances have thus fostered the emergence of novel genetic hypotheses and ideas to investigate disease-causative genetic variations. The genetic underpinnings of a number of sporadic complex diseases is now becoming partly explained and more major breakthroughs for complex traits genomics should be expected in the near future.
Could Inbred Cases Identified in GWAS Data Succeed in Detecting Rare Recessive Variants Where Affected Sib-Pairs Have Failed?
Authors: Génin Emmanuelle , Sahbatou Mourad , Gazal Steven , Babron Marie-Claude , Perdry Hervé , Leutenegger Anne-Louise
Published: April 2013

To detect fully penetrant rare recessive variants that could constitute Mendelian subentities of complex diseases, we propose a novel strategy, the HBD-GWAS strategy, which can be applied to genome-wide association study (GWAS) data. This strategy first involves the identification of inbred individuals among cases using the genome-wide SNP data and then focuses on these inbred affected individuals and searches for genomic regions of shared homozygosity by descent that could harbor rare recessive disease-causing variants. In this second step, analogous to homozygosity mapping, a heterogeneity lod-score, HFLOD, is computed to quantify the evidence of linkage provided by the data. In this paper, we evaluate this strategy theoretically under different scenarios and compare its performances with those of linkage analysis using affected sib-pair (ASP) data. If cases affected by these Mendelian subentities are not enriched in the sample of cases, the HBD-GWAS strategy has almost no power to detect them, unless they explain an important part of the disease prevalence. The HBD-GWAS strategy outperforms the ASP linkage strategy only in a very limited number of situations where there exists a strong allelic heterogeneity. When several rare recessive variants within the same gene are involved, the ASP design indeed often fails to detect the gene, whereas, by focusing on inbred individuals using the HBD-GWAS strategy, the gene might be detected provided very large samples of cases are available.
Does Accounting for Gene-Environment Interactions Help Uncover Association between Rare Variants and Complex Diseases?
Authors: Kazma Rémi , Cardin Niall J. , Witte John S.
Published: April 2013

Objective: To determine whether accounting for gene-environment (G×E) interactions improves the power to detect associations between rare variants and a disease, we have extended three statistical methods and compared their power under various simulated disease models. Methods: To test for association of a group of rare variants with a disease, Min-P uses the lowest p value within the group of variants, CAST (Cohort Allelic Sums Test) uses an indicator variable to quantify the rare alleles within the group of variants, and SKAT (Sequence Kernel Association Test) uses a logistic regression based on kernel machine. For each method, we incorporate a term for the G×E interaction and test for association and interaction jointly. Results: When testing for disease association with a set of rare variants, accounting for G×E interactions can improve power in specific situations (pure interaction or high proportion of causal variants interacting with the environment). However, the power of this approach can decrease, in particular in the presence of main genetic or environmental effects. Among the methods compared, the optimized and weighted SKAT performed best, whether to test for genetic association or to test it jointly with G×E interactions. Conclusion: This approach can be used in specific situations but is not appropriate for a primary analysis.
Insulin Resistance and Risk of Incident Heart Failure
Authors: Banerjee Dipanjan , Biggs Mary L. , Mercer Laina , Mukamal Kenneth , Kaplan Robert , Barzilay Joshua , Kuller Lewis , Kizer Jorge R. , Djousse Luc , Tracy Russell , Zieman Susan , Lloyd-Jones Donald , Siscovick David , Carnethon Mercedes
Published: April 2013

Background—

Patients with heart failure (HF) have higher fasting insulin levels and a higher prevalence of insulin resistance as compared with matched controls. Insulin resistance leads to structural abnormalities in the heart, such as increased left atrial size, left ventricular mass, and alterations in transmitral velocity that can precede the diagnosis of HF. It is not known whether insulin resistance precedes the development of HF or whether the relationship between insulin resistance and HF is present among adults with HF caused by nonischemic heart disease.

Methods and Results—

We examined 4425 participants (60% women) from the Cardiovascular Health Study after excluding those with HF, myocardial infarction, or treated diabetes mellitus at baseline. We used Cox proportional hazards models to estimate the relative risk of incident HF associated with fasting insulin measured at study entry. There were 1216 cases of incident HF (1103 without antecedent myocardial infarction) during a median follow-up of 12 years (maximum, 19 years). Fasting insulin levels were positively associated with the risk of incident HF (hazard ratio, 1.10; 95% confidence interval, 1.05–1.15, per SD change) when adjusted for age, sex, race, field center, physical activity, smoking, alcohol intake, high-density lipoprotein-cholesterol, total cholesterol, systolic blood pressure, and waist circumference. The association between fasting insulin levels and incident HF was similar for HF without antecedent myocardial infarction (hazard ratio, 1.10; 95% confidence interval, 1.05–1.15). Measures of left atrial size, left ventricular mass, and peak A velocity at baseline were associated both with fasting insulin levels and with HF; however, additional statistical adjustment for these parameters did not completely attenuate the insulin-HF estimate (hazard ratio, 1.08; 95% confidence interval, 1.03–1.14 per 1-SD increase in fasting insulin).

Conclusions—

Fasting insulin was positively associated with adverse echocardiographic features and risk of subsequent HF in Cardiovascular Health Study participants, including those without an antecedent myocardial infarction.

Clinical Trial Registration—

URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT00005133.
Left Ventricular Systolic Dysfunction, Heart Failure, and the Risk of Stroke and Systemic Embolism in Patients With Atrial Fibrillation
Authors: McMurray John J.V. , Ezekowitz Justin A. , Lewis Basil S. , Gersh Bernard J. , van Diepen Sean , Amerena John , Bartunek Jozef , Commerford Patrick , Oh Byung-Hee , Harjola Veli-Pekka , Al-Khatib Sana M. , Hanna Michael , Alexander John H. , Lopes Renato D. , Wojdyla Daniel M. , Wallentin Lars , Granger Christopher B. ,   for the ARISTOTLE Committees and Investigators
Published: April 2013

Background—

We examined the risk of stroke or systemic embolism (SSE) conferred by heart failure (HF) and left ventricular systolic dysfunction (LVSD) in the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation Trial (ARISTOTLE), as well as the effect of apixaban versus warfarin.

Methods and Results—

The risk of a number of outcomes, including the composite of SSE or death (to take account of competing risks) and composite of SSE, major bleeding, or death (net clinical benefit) were calculated in 3 patient groups: (1) no HF/no LVSD (n=8728), (2) HF/no LVSD (n=3207), and (3) LVSD with/without symptomatic HF (n=2736). The rate of both outcomes was highest in patients with LVSD (SSE or death 8.06; SSE, major bleeding, or death 10.46 per 100 patient-years), intermediate for HF but preserved LV systolic function (5.32; 7.24), and lowest in patients without HF or LVSD (1.54; 5.27); each comparison
P
<0.0001. Each outcome was less frequent in patients treated with apixaban: in all ARISTOTLE patients, the apixaban/warfarin hazard ratio for SSE or death was 0.89 (95% confidence interval, 0.81–0.98;
P
=0.02); for SSE, major bleed, or death it was 0.85 (0.78–0.92;
P
<0.001). There was no heterogeneity of treatment effect across the 3 groups.

Conclusions—

Patients with LVSD (with/without HF) had a higher risk of SSE or death (but similar rate of SSE) compared with patients with HF but preserved LV systolic function; both had a greater risk than patients without either HF or LVSD. Apixaban reduced the risk of both outcomes more than warfarin in all 3 patient groups.

Clinical Trial Registration—

URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT00412984.
Agreement Among Cardiovascular Disease Risk Calculators
Authors: Allan G. Michael , Nouri Faeze , Korownyk Christina , Kolber Michael R. , Vandermeer Ben , McCormack James
Published: April 2013

Background—

Use of cardiovascular disease risk calculators is often recommended by guidelines, but research on consistency in risk assessment among calculators is limited.

Method and Results—

A search of PubMed and Google was performed. Five clinicians selected 25 calculators by independent review. Hypothetical patients were created with the use of 7 risk factors (age, sex, smoking, blood pressure, high-density lipoprotein, total cholesterol, and diabetes mellitus) dichotomized to high and low, generating 2
7
patients (128 total). These patients were assessed by each calculator by 2 clinicians. Risk estimates (and assigned risk categories) were compared among calculators. Selected calculators were from 8 countries, used 5- or 10-year predictions, and estimated either cardiovascular disease or coronary heart disease. With the use of 3 risk categories (low, medium, and high), the 25 calculators categorized each patient into a mean of 2.2 different categories, and 41% of unique patients were assigned across all 3 risk categories. Risk category agreement between pairs of calculators was 67%. This did not improve when analysis was limited to just the 10-year cardiovascular disease calculators. In nondiabetics, the highest calculated risk estimate from a calculator averaged 4.9 times higher (range, 1.9–13.3) than the lowest calculated risk estimate for the same patient. This did not change meaningfully for diabetics or when the analysis was limited to 10-year cardiovascular disease calculators.

Conclusions—

The decision as to which calculator to use for risk estimation has an important impact on both risk categorization and absolute risk estimates. This has broad implications for guidelines recommending therapies based on specific calculators.
Finding the Common Good in an Era of Dysfunctional Governance
Authors: Mann Thomas E. , Ornstein Norman J.
Published: April 2013

The framers designed a constitutional system in which the government would play a vigorous role in securing the liberty and well-being of a large and diverse population. They built a political system around a number of key elements, including debate and deliberation, divided powers competing with one another, regular order in the legislative process, and avenues to limit and punish corruption. America in recent years has struggled to adhere to each of these principles, leading to a crisis of governability and legitimacy. The roots of this problem are twofold. The first is a serious mismatch between our political parties, which have become as polarized and vehemently adversarial as parliamentary parties, and a separation-of-powers governing system that makes it extremely difficult for majorities to act. The second is the asymmetric character of the polarization. The Republican Party has become a radical insurgency – ideologically extreme, scornful of facts and compromise, and dismissive of the legitimacy of its political opposition. Securing the common good in the face of these developments will require structural changes but also an informed and strategically focused citizenry.
Unions & Civic Engagement: How the Assault on Labor Endangers Civil Society
Authors: Stern Andy
Published: April 2013

American trade unions are a crucial segment of civil society that enriches our democracy. Union members are stewards of the public good, empowering the individual through collective action and solidarity. While union density has declined, the U.S. labor movement remains a substantial political and economic force. But the relentless attacks by the political right and its corporate allies could lead to an erosion of civic engagement, further economic inequality, and a political imbalance of power that can undermine society. The extreme assault on unions waged by Republicans in Wisconsin, Ohio, Michigan, and at a national level must be countered by a revitalized labor movement and by those who understand that unions are positive civil actors who bring together individuals who alone have little power. Unions need both structural reform and greater boldness; there are moments in which direct action and dramatic militancy can bring about positive social change. The current assault on labor can be rebuffed, and unions can expand their role as stewards for the public good and as defenders of efforts by the 99 percent to reduce inequality and protect democracy.
Philanthropy, the Nonprofit Sector & the Democratic Dilemma
Authors: Hall Peter Dobkin
Published: April 2013

The central dilemma of American democracy is the tension between “voice” and “equality”: between the Constitution's unconditional guarantees of citizens' expressive, associational, and property rights and the legal and political equality that is the foundation of majoritarian decision-making. Philanthropy and nonprofit organizations – which enable citizens to give money and time to support causes in which they believe – have posed this dilemma with unusual force, allowing moneyed minorities to oppose and sometimes overwhelm the popular will. In the past, these assertions of private power have inevitably aroused popular opposition producing legislative and regulatory outcomes that have maintained a balance between voice and equality. Today, with unprecedented accumulations of wealth and legal changes permitting the unrestricted use of wealth in politics, the unchallenged exercise of private power through philanthropy and the nonprofit sector poses grave threats to the democratic process.
Valuing Compromise for the Common Good
Authors: Gutmann Amy , Thompson Dennis
Published: April 2013

Pursuing the common good in a pluralist democracy is not possible without making compromises. Yet the spirit of compromise is in short supply in contemporary American politics. The permanent campaign has made compromise more difficult to achieve, as the uncompromising mindset suitable for campaigning has come to dominate the task of governing. To begin to make compromise more feasible and the common good more attainable, we need to appreciate the distinctive value of compromise and recognize the misconceptions that stand in its way. A common mistake is to assume that compromise requires finding the common ground on which all can agree. That undermines more realistic efforts to seek classic compromises, in which each party gains by sacrificing something valuable to the other, and together they serve the common good by improving upon the status quo. Institutional reforms are desirable, but they, too, cannot get off the ground without the support of leaders and citizens who learn how and when to adopt a compromising mindset.
Reestablishing the Commons for the Common Good
Authors: Gardner Howard
Published: April 2013

For individuals living in a small community, the notion of “common good” seems almost natural; it can be thought of simply as neighborly morality. However, in a complex modern society, it is far more challenging for individuals to define and agree upon what is the common good. Nonetheless, two contemporary roles would benefit from embracing a broader sense of the good: 1) membership in a profession; and 2) membership in a polity. Drawing on findings from the GoodWork Project, I describe how the common good can become a guiding value in the professional and civic realms; discuss threats to such guiding values; and suggest some ways to promote the common good in contemporary American society.
The Democratic Spirit
Authors: Appiah Kwame Anthony
Published: April 2013

There is a famous paradox about democracy: most forms of participation make no obvious difference to political outcomes and yet people act anyway. I argue that they are more likely to act politically if they have certain attitudes and commitments; and that productive attitudes of the right kind can be sustained by a culture in which two kinds of honor are central. One kind of honor is collective: it is the honor of nations, which is the concern of the patriot. Another is the honor of citizens, who are worthy of respect because they contribute to the practices that serve the republic. I suggest some practices we Americans might want to take up and honor for the sake of our own republic today, drawing attention to two discoveries in social psychology that could be productively brought to bear in our political life: namely, the Ben Franklin effect and the Contact Hypothesis.
Retinotopic and Lateralized Processing of Spatial Frequencies in Human Visual Cortex during Scene Categorization
Authors: Musel Benoit , Bordier Cécile , Dojat Michel , Pichat Cédric , Chokron Sylvie , Le Bas Jean-François , Peyrin Carole
Published: April 2013

Using large natural scenes filtered in spatial frequencies, we aimed to demonstrate that spatial frequency processing could not only be retinotopically mapped but could also be lateralized in both hemispheres. For this purpose, participants performed a categorization task using large black and white photographs of natural scenes (indoors vs. outdoors, with a visual angle of 24° × 18°) filtered in low spatial frequencies (LSF), high spatial frequencies (HSF), and nonfiltered scenes, in block-designed fMRI recording sessions. At the group level, the comparison between the spatial frequency content of scenes revealed first that, compared with HSF, LSF scene categorization elicited activation in the anterior half of the calcarine fissures linked to the peripheral visual field, whereas, compared with LSF, HSF scene categorization elicited activation in the posterior part of the occipital lobes, which are linked to the fovea, according to the retinotopic property of visual areas. At the individual level, functional activations projected on retinotopic maps revealed that LSF processing was mapped in the anterior part of V1, whereas HSF processing was mapped in the posterior and ventral part of V2, V3, and V4. Moreover, at the group level, direct interhemispheric comparisons performed on the same fMRI data highlighted a right-sided occipito-temporal predominance for LSF processing and a left-sided temporal cortex predominance for HSF processing, in accordance with hemispheric specialization theories. By using suitable method of analysis on the same data, our results enabled us to demonstrate for the first time that spatial frequencies processing is mapped retinotopically and lateralized in human occipital cortex.
Abnormal Causal Attribution Leads to Advantageous Economic Decision-making: A Neuropsychological Approach
Authors: Koscik Timothy R. , Tranel Daniel
Published: April 2013

People tend to assume that outcomes are caused by dispositional factors, for example, a person's constitution or personality, even when the actual cause is due to situational factors, for example, luck or coincidence. This is known as the “correspondence bias.” This tendency can lead normal, intelligent persons to make suboptimal decisions. Here, we used a neuropsychological approach to investigate the neural basis of the correspondence bias, by studying economic decision-making in patients with damage to the ventromedial pFC (vmPFC). Given the role of the vmPFC in social cognition, we predicted that vmPFC is necessary for the normal correspondence bias. In our experiment, consistent with expectations, healthy (n = 46) and brain-damaged (n = 30) comparison participants displayed the correspondence bias during economic decision-making and invested no differently when given dispositional or situational information. By contrast, vmPFC patients (n = 17) displayed a lack of correspondence bias and invested more when given dispositional than situational information. The results support the conclusion that vmPFC is critical for normal social inference and the correspondence bias. The findings help clarify the important (and sometimes disadvantageous) role of social inference in economic decision-making.
When Two Become One: The Role of Oxytocin in Interpersonal Coordination and Cooperation
Authors: Arueti Maayan , Perach-Barzilay Nufar , Tsoory Michael M. , Berger Barry , Getter Nir , Shamay-Tsoory Simone G.
Published: April 2013

Cooperation involves intentional coordinated acts performed to achieve potentially positive outcomes. Here we present a novel explanatory model of cooperation, which focuses on the role of the oxytocinergic system in promoting interpersonal coordination and synchrony. Cooperation was assessed using a novel computerized drawing task that may be performed individually or cooperatively by two participants who coordinate their actions. Using a within-subject crossover design, 42 participants performed the task alone and with a partner following the administration of placebo and oxytocin 1 week apart. The data indicate that following placebo administration, participants performed better alone than in pairs. Yet, the administration of oxytocin improved paired performance up to the level of individual performance. This effect depended on the personality traits of cooperativeness or competitiveness. It is concluded that oxytocin may play a key role in enhancing social synchrony and coordination of behaviors required for cooperation.
God in Rabbinic Tradition: Human Reasoning and Divine Authority
Authors: Hashkes Hannah
Published: April 2013

Abstract

In this paper I contend that rabbinic reasoning reflects a conceptual framework that is based upon a dual notion of divinity. The first notion is of a transcendent God, who created the world and is removed from it. The second is a notion of an immanent God who prescribes law and participates in the human activity of transmitting it. Here God functions as a “first among equals.” The transcendent notion lends rabbinic reasoning its truth value and absolute authority, while the immanent notion allows God’s commanding will to continue its role in prescribing communal life through history. Rabbinic reasoning is the logic derived from this dual notion. Through readings of rabbinic works I demonstrate that the rabbis developed this reasoning by creating conceptual spaces that assume these two notions. These conceptual spaces are based upon the human structures of a court of law and a house of worship, within which processes of reasoning occur.
VESSELS IN CARDWELLIA SUBLIMIS CONTAINING ALUMINIUM AND MAGNESIUM SALTS
Authors: Hillis W. E.
Published: April 2013

White deposits occurred in isolated, randomly located vessels in areas of a Cardwellia sublimis sample. They were shown to contain aluminium cation with about one-tenth the amount of magnesium cation. Other studies have indicated the main salt to be the very insoluble aluminium succinate. Deposits may fill cross-sections of vessels which are only occasionally seen in association with ray parenchyma. It is concluded that the salts are formed at the pits of particular associations of ray parenchyma cells with vessels and the salts are then forced into the rest of the vessel.
INCREMENT PUNCHER: A tool for extracting small cores of wood and bark from living trees
Authors: Forster Theodor , Schweingruber Fritz Hans , Denneler Bernhard
Published: April 2013

A newly designed and easy-to-use increment puncher (in French: minisonde de prélèvement; in German: Zuwachsstecher; in Italian: puntura incrementale) allows the extraction of wood and bark cores from living tree stems for the study of radial increment, cell wall formation, lignification and wound reactions. This article describes the technical features and gives instructions for use. The biological reactions in the injured zone surrounding the punched holes are presented in a case study on eastern white cedar (Thuja occidentalis L.).
CELL STRUCTURE IN TREE RINGS: NOVEL METHODS FOR PREPARATION AND IMAGE ANALYSIS OF LARGE CROSS SECTIONS
Authors: Spiecker Heinrich , Schinker Martin G. , Hansen Jörg , Park Young-In , Ebding Tilman , Döll Walter
Published: April 2013

A new method for the preparation of wood samples for high-resolution reflected-light microscopy in combination with a species-specific image analysis system is introduced. The method is based on an ultraprecise single-point diamond flycutter equipped with air bearings and functions on the basis of a rotating diamond edge. Extensive and very smooth surfaces can be produced on increment cores as well as entire cross sections. Hence, this technique provides the prerequisites for a continuous microscopic analysis across large tree-ring sequences, or entire cross sections. Patching or sub-sectioning is not required. The high-resolution analysis of cell structures of spruce and oak presented here introduces new approaches for describing and predicting reactions of diameter growth to various environmental events.
A COMPARISON OF TREE-RING FEATURES IN PICEA ABIES AS CORRELATED WITH CLIMATE
Authors: Wimmer Rupert , Grabner Michael
Published: April 2013

This paper presents an analysis of 16 anatomical variables measured on 20 spruce trees [Picea abies (L.) Karst.] from sites in the managed forest district Seyde, Eastern Ore Mountains, south of Dresden, Germany. Ring width and latewood proportion did not show significant relationships with monthly climatic data, whereas maximum density, latewood cell-wall proportion and latewood density were highly correlated with temperature and precipitation. The climatic signals expressed in resin duct density, ray height, tracheid length and microfibril angles were less pronounced. Of 16 tree-ring parameters, densitometry – as an indirect measure of xylem anatomy – has again shown its great potential to record climatic conditions.
ANATOMICAL CHARACTERISTICS AND PROPERTIES OF KENAF STEMS (HIBISCUS CANNABINUS)
Authors: Voulgaridis Elias , Passialis Costas , Grigoriou Athanassios
Published: April 2013

From a kenaf plantation (Hibiscus cannabinus L.) established in North Greece, a number of stem sections were taken from three positions (base, middle and top) and cell morphology, anatomical appearance under SEM and basic technical properties were observed and determined. Kenaf plants had a maximum height of 2.53 m, with a mean basal diameter of 1.91 cm. The wood is the most abundant tissue with proportions up to 77% in cross-section area and up to 61.5% in weight. Wood proportions decrease, pith proportions increase and bark proportions remain constant from the base to the top of the stems. The dry density of stems ranged between 0.27–0.31 g /cm3, while that of wood ranged between 0.22–0.43 g /cm3 along the stems. The contents of hot water soluble extractives ranged between 10.6% and 20.4% and those of dichloromethane soluble extractives ranged between 0.7% and 1.2% for bark, wood and pith. Microscopic examination of stems and of macerated material showed that bark consists of thick and long (2,330 μm) fibres whilst pith consists of polygonal parenchymatous cells. Wood is diffuse- porous, fibres average 840 μm long, vessel members average 330 μm long and 45 μm in diameter and orthogonal parenchymatous cells are 90 μm long. Fibre lengths in both bark and wood increase from the base to the top of stem. Vessel diameters decrease from base to top, while vessel member lengths remain constant from base to middle but decrease at the top of the stem.
OCCURRENCE OF PERFORATED RAY CELLS IN GENERA OF PACHYCEREEAE (CACTACEAE)
Authors: Terrazas Teresa
Published: April 2013

Perforated ray cells are reported for the first time for 16 species of seven genera of Pachycereeae. The perforated ray cells are shorter than vessel elements and have simple perforation plates and small alternate intervascular pits. Among Cactaceae these specialised cells seem to be related with splitting of the tall rays.
EVIDENCE FOR GONDWANAN ORIGINS FOR SASSAFRAS (LAURACEAE)? LATE CRETACEOUS FOSSIL WOOD OF ANTARCTICA
Authors: Poole Imogen , Richter Hans G. , Francis Jane E.
Published: April 2013

Sassafrasoxylon gottwaldii sp. nov. is a new taxon for fossil wood with a suite of features diagnostic of Sassafras Nees & Eberm. of the Lauraceae. The fossil wood described is from Late Cretaceous (Santonian- Maastrichtian) sediments of the northern Antarctica Peninsula region. This new species of Sassafrasoxylon Brezinová et Süss resembles the species of extant Sassafras in being distinctly ring-porous, having vessel elements with simple perforation plates and very occasional scalariform plates with relatively few bars in the narrowest latewood vessels, alternate intervascular pitting, marginal (initial) parenchyma bands and paratracheal vasicentric parenchyma in the latewood, multiseriate rays and oil and /or mucilage cells. The fossils were found as isolated pieces of wood and therefore it is not certain whether the parent plant was Sassafras-like in all characters. Consequently the fossils have been placed in an organ genus rather than in extant Sassafras. This is the oldest record of an organ with features closest to extant Sassafras and may suggest that Sassafras first appeared in Gondwana and later radiated into the Northern Hemisphere. The distribution of extant Sassafras in North America and East Asia may represent a relict of a geographically more widespread taxon in the past.
ANALYSIS OF CAMBIUM AND DIFFERENTIATING VESSEL ELEMENTS IN KALOPANAX PICTUS USING RESIN CAST REPLICAS
Authors: Kitin Peter , Sano Yuzou , Funada Ryo
Published: April 2013

A resin-casting method with subsequent scanning electron microscopy (SEM) was used to examine the three-dimensional (3-D) shapes of cells and the cell walls of cambium and differentiating xylem. Glutaraldehyde- fixed and dehydrated specimens were embedded in polystyrene and then organic material was removed by digestion with acidic solutions or enzymes. The acidic solutions used for treatment were sulphuric acid and a mixture of acetic acid and hydrogen peroxide and the enzymes used for treatment were pectinase and cellulase, with a final treatment with sodium hypochlorite. Both methods could be used for studies of the differentiation of cambial cells; however, digestion with enzymes allowed better preservation of the 3-D organisation of the tissue. Negative replicas of inner surfaces of cell walls of differentiating vessel elements revealed the sequential stages of the development of bordered pits and perforation plates. Future bordered pits at the early stages of the differentiation of cell walls were demarcated by the accumulation of organic material between adjacent pit membranes. Subsequent deposition of cell wall material resulted in formation of pit cavities and the rims of perforation plates.
CONFOCAL LASER SCANNING MICROSCOPY OF WATER UPTAKE DURING THE RECOVERY OF COMPRESSED AND DRYING-SET WOOD
Authors: Abe Hisashi , Funada Ryo , Kuroda Naohiro , Furusawa Osamu , Shibagaki Masayuki , Fujii Tomoyuki
Published: April 2013

The initial uptake of water by small fragments of compressed and drying- set wood of Cryptomeria japonica D. Don was monitored by confocal laser scanning microscopy (CLSM) using an aqueous solution of the fluorescent dye acridine orange. CLSM allowed visualization of the recovery over time of compressed and drying-set wood and the uptake of water by the specimens. Furthermore, CLSM allowed us to monitor the structure of deformed tracheids under atmospheric conditions. Increases in the compression ratio increased the time required for the uptake of water. The uptake of water was detected first between deformed and undeformed regions of compressed and drying-set wood at all compression ratios tested.
SHRINKAGE OF THE GELATINOUS LAYER OF POPLAR AND BEECH TENSION WOOD
Authors: Clair Bruno , Thibaut Bernard
Published: April 2013

Macroscopic longitudinal shrinkage of beech and poplar tension wood is higher than in normal wood. This shrinkage is the result of mechanical interactions of cell wall layers. SEM observation of cut, dried surfaces showed that longitudinal shrinkage is much greater in the gelatinous layer than in other layers. AFM topographic images of the same cells, both in water and in air-dry conditions, confirm this result. Measurements on sections indicate around 4.7% longitudinal shrinkage for the G layer.
WOOD ANATOMY OF CYATHOSTEGIA MATHEWSII (SWARTZIEAE, PAPILIONOIDEAE, LEGUMINOSAE)
Authors: Gasson Peter , Wray Elspeth J.
Published: April 2013

The genus Cyathostegia consists of one or possibly two species from Ecuador and Peru. The wood anatomy of C. mathewsii (Benth.) Schery is described, thereby completing generic coverage of wood anatomy in the tribe Swartzieae sensu Polhill (1994b). In Cyathostegia, vessels are mainly in radial multiples, axial parenchyma is relatively sparse, storied and mainly paratracheal, and rays are 1–2-seriate and irregularly storied. Its wood anatomy is compared with that of other genera in the closely related tribes Sophoreae and Swartzieae, both of which have included Cyathostegia. The similarities and differences between Cyathostegia, Ateleia and Amburana are emphasised.
COMPARISON OF SEGMENTATION METHODS FOR DIGITAL IMAGE ANALYSIS OF CONFOCAL MICROSCOPE IMAGES TO MEASURE TRACHEID CELL DIMENSIONS
Authors: Moëll Mattias K. , Donaldson Lloyd A.
Published: April 2013

Image analysis is a common tool for measuring tracheid cell dimensions. When analyzing a digital image of a transverse cross section of wood, one of the initial procedures is that of segmentation. This involves classifying a picture element (pixel) as either cell wall or lumen. The accuracy of tracheid measurements is dependent on how well the result of the segmentation procedure corresponds to the true distributions of cell wall or lumen pixels. In this paper a comparison of segmentation methods is given. The effect of segmentation method on measurements is investigated and the performance of each method is discussed.

We demonstrate that automated segmentation methods remove observer bias and are thus capable of more reproducible results. The contrast for confocal microscope images is of such quality that one of the fastest and simplest automatic segmentation methods may be used.
WOUND EFFECTS ARREST WAVE PHENOMENA IN THE SECONDARY XYLEM OF RHAMNUS ALATERNUS (RHAMNACEAE)
Authors: Lev-Yadun Simcha
Published: April 2013

Wounding and partial girdling of stems of Rhamnus alaternus L. inhibited the formation of vessel wave patterns that are normally formed in the secondary xylem of this species. The patterns returned to normal in some of the trees in the first or in the second year after wounding. The possible hormonal regulatory mechanisms involved in the histological changes are discussed.
XENOXYLON WOOD FROM LATE JURASSIC–EARLY CRETACEOUS OF GEBEL KAMIL, EGYPT
Authors: Youssef S.G.M.
Published: April 2013

Three fossil woods, collected from Late Jurassic–Early Cretaceous of Gebel Kâmil in southwestern Egypt, were studied anatomically, and identified as Xenoxylon saadawii sp. nov. of the family Protopinaceae.
RELATIONSHIP BETWEEN WOOD DENSITY, MICROFIBRIL ANGLE AND STIFFNESS IN THINNED AND FERTILIZED PINUS RADIATA
Authors: Downes Geoffrey M. , Gwinyai Nyakuengama J. , Evans Robert , Northway Richard , Blakemore Philip , Dickson Ross L. , Lausberg Marco
Published: April 2013

The relationships between wood anatomy in standing trees and the strength of boards were examined in Pinus radiata D. Don (thinned vs thinned and fertilized) at 2 contrasting sites. Fertilizer treatments were applied after mid-rotation thinning. Logs were taper sawn and boards, near the pre-treatment / post-treatment boundary, subjected to acoustic and strength assessment. Average wood property data from a 12-mm increment core obtained prior to harvest, was extracted from the relevant portion of the radius.

In general, fertilizer resulted in lower density, higher microfibril angle (MFA) and slightly lower stiffness. However, stiffness was still relatively high as the affected wood was from the more mature portion of the radius. SilviScan density and MFA data were good predictors of stiffness. Acoustic measurements on boards were strongly correlated with board stiffness. Path analyses explained up to 45% of the variance in stiffness, as a function of estimated MOE and log sweep.
WOODS OF EUCALYPTUS – PART 2 DISTINGUISHING SPECIES FROM THE STRINGYBARK GROUP: (E. baxteri, E. globoidea, E. muelleriana, E. macrorhyncha, E. consideniana and E. sieberi)
Authors: Ilic J.
Published: April 2013

In Australia the stringybark group of eucalypts comprises at least 25 species of Eucalyptus from the botanical series Capitellatae. The species are abundant in south-eastern Australia, and four groups (white, yellow, brown and red) of the commercial timber come mainly from Victoria and New South Wales and these include E. baxteri (Benth.) Maiden, E. globoidea Blakely & Blakely, E. macrorhyncha F. Muell. ex Benth., and E. muelleriana Howitt. As with the ‘ash group’ of eucalypts, the timbers are similar in appearance, and although they are heavier than the ash group, there are some overlapping characteristics. Two additional species, E. consideniana Maiden (yertchuk) and E. sieberi L.A.S. Johnson (silvertop ash), outside the stringybark group, were studied as their woods also closely resemble those from the stringybark group.

Differences were found between the species in vessel diameter and density, ray content, amount of axial parenchyma, distinctness of growth rings, basic density and wood colour. Most of the useful differences arise from extremes of these characteristics. Eucalyptus macrorhyncha (red stringybark) can be identified when the pore number is greater than 15/mm2, the average maximum tangential diameter is less than 140 μm, by ray width and content and from the definite pink-reddish colour. Eucalyptus sieberi can be distinguished definitely from E. muelleriana, and fairly certainly from E. globoidea and E. baxteri by uniformly distributed deposits in the rays. Considerable overlap in wood structure exists among E. muelleriana, E. globoidea and E. baxteri making their separation on wood characteristics impractical. Photomicrographs illustrating various points have been included together with a key for separation between the species studied. Similarities to other species including E. acmenoides, E. microcorys, E. obliqua, E. phaeotricha, and E. pilularis are discussed.
BARK ANATOMY AND INTERCELLULAR CANALS IN THE STEM OF DELARBREA PARADOXA (ARALIACEAE)
Authors: Kolalite M. R. , Oskolski A. A. , Richter H. G. , Schmitt U.
Published: April 2013

The anatomy of the primary tissues and secondary phloem in the stem of Delarbrea paradoxa Vieill. (Araliaceae) was examined with emphasis on structure and topography of secretory canals. Secretory canal systems of primary (axial canals in cortex and pith, radial canals in medullary rays) and secondary origin (axial canals in secondary phloem, radial canals in rays of secondary phloem and secondary xylem) were distinguished. Two distinct types of axial parenchyma (sheath parenchyma near axial secretory canals, and phloem parenchyma associated with conducting elements) occur in the secondary phloem. Distribution, size and number of cells per strand, occurrence of starch, and mode of transformation during phloem collapse serve to distinguish these two types. Three stages of secretory canal development (canal formation, active secretion, and senescence) were distinguished on the basis of TEM observations. The secretory canal lumina are formed simultaneously with the differentiation of meristematic cells into epithelial secretory cells. During the active secretion phase the epithelial cells contain leucoplasts aggregated into small groups, each accompanied by 2 to 3 mitochondria. These aggregations indicate terpene production in the cell. The secretion of terpenes is accompanied by swelling and loosening of the cell walls facing the canal lumina. Secretory processes were not indicated in the highly vacuolated senescent epithelial cells.
INFLUENCE OF CLIMATE CHANGES ON TREE-RING CHARACTERISTICS OF SCOTS PINE PROVENANCES IN SOUTHERN SIBERIA (FOREST-STEPPE)
Authors: Savva Yu.V. , Schweingruber F.H. , Vaganov E.A. , Milyutin L.I.
Published: April 2013

Scots pine provenances from all over Russia planted in 1964 at the forest- steppe zone were analyzed. Eight tree-ring characteristics from 12 different provenances were measured densitometrically. The time span of tree-ring observation covers the period from 1969 to 1997. The sensitivity coefficient of latewood width, latewood and maximum densities and latewood percentage decreases in relation to the increasing latitude of the provenances. The growth of all studied provenances is dictated by the local weather and climate. The correlation coefficients of indices between the local provenance and the other provenances are not lower than 0.46–0.97, and the synchronicity coefficients are minimally 0.84. The Euclidean distances vary from 0.11 to 0.13 between the local provenance and the other provenances. All statistical parameters show that the interannual variability reflects the prevailing influence of the local weather conditions. Variability of weather conditions determines up to 87% of the growth variability in the forest-steppe of southern Siberia.
CHANGES CAUSED BY MID-ROTATION FERTILIZER APPLICATION TO THE FIBRE ANATOMY OF PINUS RADIATA
Authors: Nyakuengama John Gwinyai , Downes Geoffrey M. , Ng Jane
Published: April 2013

Effects of nitrogen (N) and phosphorus (P) fertilizers on average fibre radial diameter, tangential diameter, wall thickness and number of fibres per unit area were studied over 7 years of growth in radiata pine. Stands were in mid-rotation, thinned and treatments replicated 4 times at 3 sites. Compared to a thinned, unfertilized control, N decreased and P increased fibre radial diameter. Only N decreased fibre radial diameter, thereby increasing the number of fibres per unit area. All fertilizer treatments decreased fibre wall thickness. Responses in ring width and fibre properties, other than fibre tangential diameter peaked 2 years following fertiliser application, before gradually disappearing after 4–5 years. Fertilizer effects on fibre properties diminished at different rates, causing significant interactions with time. Ring width had little effect on density. Changes in density and fibre coarseness were attributed to changes in fibre wall thickness more than fibre radial diameter and tangential diameter. The largest decrease in density and fibre coarseness in the combined N and P treatment was explained mostly by thinner walls.