bluuebunny/crossref_metadata_2025 huggingface dataset:
Induction of a Small Heat Shock Protein and Its Functional Roles inNicotianaPlants in the Defense Response againstRalstonia solanacearum
Authors: Maimbo Milimo , Ohnishi Kouhei , Hikichi Yasufumi , Yoshioka Hirofumi , Kiba Akinori
Published: October 2007

In tobacco (Nicotiana tabacum), Ralstonia solanacearum OE1-1 (RsOE1-1) is pathogenic, whereas R. solanacearum 8107 (Rs8107) is nonpathogenic and induces the hypersensitive response (HR). To elucidate the molecular mechanisms of plant-R. solanacearum interactions, we used differential display to isolate a cDNA fragment, A6, regulated in tobacco by inoculation with RsOE1-1. The deduced amino acid sequence predicted from full-length A6-cDNA showed similarity to small heat shock proteins from Arabidopsis (Arabidopsis thaliana; hypothetical protein), Medicago truncatula, and Cucumis melo; we therefore designated A6 to correspond to Ntshsp17 (for tobacco small heat shock protein 17). Recombinant Ntshsp17 overproduced in Escherichia coli exhibited molecular chaperone function. Expression of Ntshsp17 was increased in tobacco leaves inoculated with both RsOE1-1 and Rs8107. Expression was induced by heat treatment and by treatment with aminocyclopropane carboxylic acid, hydrogen peroxide, methyl jasmonate, and salicylic acid. Ntshsp17 expression was induced by inoculation with a HR and pathogenicity gene mutant of Rs8107 that does not induce the HR, but not by Agrobacterium-mediated transient expression of INF1, an HR elicitor. In Nbshsp17-silenced plants (an Ntshsp17 ortholog in Nicotiana benthamiana), expression of ETHYLENE-RESPONSE ELEMENT-BINDING PROTEIN, PATHOGENESIS-RELATED1a (PR1a), and PR4 genes was compromised, but expression of ELONGATION FACTOR1α was scarcely affected. Appearance of the HR was not affected in the silenced plants. In the silenced plants, growth of Rs8107 was accelerated. Bacterial growth and wilt symptoms elicited by RsOE1-1 were also accelerated in the silenced plants. These results indicate that this small heat shock protein might have a role in HR-independent defenses in Nicotiana plants.
Crystal structures of the N‐terminal kinase domain of human RSK1 bound to three different ligands: Implications for the design of RSK1 specific inhibitors
Authors: Ikuta Mari , Kornienko Maria , Byrne Noel , Reid John C. , Mizuarai Shinji , Kotani Hidehito , Munshi Sanjeev K.
Published: October 2007

The p90 ribosomal S6 kinases (RSKs) also known as MAPKAP‐Ks are serine/threonine protein kinases that are activated by ERK or PDK1 and act as downstream effectors of mitogen‐activated protein kinase (MAPK). RSK1, a member of the RSK family, contains two distinct kinase domains in a single polypeptide chain, the regulatory C‐terminal kinase domain (CTKD) and the catalytic N‐terminal kinase domain (NTKD). Autophosphorylation of the CTKD leads to activation of the NTKD that subsequently phosphorylates downstream substrates. Here we report the crystal structures of the unactivated RSK1 NTKD bound to different ligands at 2.0 Å resolution. The activation loop and helix αC, key regulatory elements of kinase function, are disordered. The DFG motif of the inactive RSK1 adopts an “active‐like” conformation. The β‐PO4 group in the AMP–PCP complex adopts a unique conformation that may contribute to inactivity of the enzyme. Structures of RSK1 ligand complexes offer insights into the design of novel anticancer agents and into the regulation of the catalytic activity of RSKs.
CON: Should Aspirin Be Used in All Women Older Than 65 Years to Prevent Stroke?
Authors: Buring Julie E.
Published: October 2007

A goal of the Women's Health Study was to evaluate the balance of benefits and risks of low‐dose aspirin in the primary prevention of stroke in healthy women. A total of 39,876 female health care professionals aged 45 years and older were randomly assigned to either low‐dose aspirin (100 mg every other day) or placebo and followed for an average of 10 years. In the overall study population, aspirin significantly lowered the risk of total and ischemic stroke without affecting the risk of myocardial infarction or death from cardiovascular causes, leading to a nonsignificant finding with respect to the primary end point of total cardiovascular disease. In women aged 65 years or older, aspirin significantly reduced the risk of ischemic stroke, as well as myocardial infarction and total cardiovascular disease. While the findings suggest that aspirin should be considered for primary prevention of stroke in women aged 65 years or older, the balance of benefits and risks would not support recommending aspirin for all women in this age group. The discussion on whether to use aspirin should be had on an individual basis, assessing the net risks and benefits.
Continuing Medical Education: Peyronie's Disease (CME)
Authors: Bella Anthony J. , Perelman Michael A. , Brant William O. , Lue Tom F.
Published: October 2007

Introduction

The management of Peyronie's disease (PyD) presents several challenges to the clinician. Despite progress in the understanding of PyD on several fronts, it remains a physically and psychologically devastating condition for the affected patient and partner.

Aim

The purpose of this Continuing Medical Education article is to review contemporary knowledge of the epidemiology, pathophysiology, evaluation, and management of PyD, thus enabling best-practice management.

Methods

An English-language MEDLINE review was performed from 1990 to present-day for PyD.

Main Outcome Measure

Current state of, and new developments in, PyD.

Results

Recent studies have established a new paradigm for the natural history and epidemiology of PyD. Prevalence approaches 5%, while less than 20% of men report spontaneous resolution of deformity. The psychological sequelae on both patient and partner are underrepresented in literature; data gleaned from select Internet websites have better established Peyronie's effects on psyche and relationships. For the majority of patients, evaluation, information, and reassurance is sufficient. Few medical treatment options are supported by data from well-designed placebo-controlled trials. For men unresponsive to nonoperative therapies, plication, grafting, or implantation of a penile prosthesis are surgical management options.

Conclusions

PyD does not invariably progress to a complete loss of the ability for sexual intercourse. Should deformities preclude intercourse, well-established medical or surgical options may be considered; indeed, using one or more of the treatment approaches outlined can, in most cases, result in adequate restoration of sexual function.
Pleasure and Orgasm in Women with Female Genital Mutilation/Cutting (FGM/C)
Authors: Catania Lucrezia , Abdulcadir Omar , Puppo Vincenzo , Verde Jole Baldaro , Abdulcadir Jasmine , Abdulcadir Dalmar
Published: October 2007

Introduction

Female genital mutilation/cutting (FGM/C) violates human rights. FGM/C women's sexuality is not well known and often it is neglected by gynecologists, urologists, and sexologists. In mutilated/cut women, some fundamental structures for orgasm have not been excised.

Aim

The aim of this report is to describe and analyze the results of four investigations on sexual functioning in different groups of cut women.

Main Outcome Measure

Instruments: semistructured interviews and the Female Sexual Function Index (FSFI).

Methods

Sample: 137 adult women affected by different types of FGM/C; 58 young FGM/C ladies living in the West; 57 infibulated women; 15 infibulated women after the operation of defibulation.

Results

The group of 137 women, affected by different types of FGM/C, reported orgasm in almost 86%, always 69.23%; 58 mutilated young women reported orgasm in 91.43%, always 8.57%; after defibulation 14 out of 15 infibulated women reported orgasm; the group of 57 infibulated women investigated with the FSFI questionnaire showed significant differences between group of study and an equivalent group of control in desire, arousal, orgasm, and satisfaction with mean scores higher in the group of mutilated women. No significant differences were observed between the two groups in lubrication and pain.

Conclusion

Embryology, anatomy, and physiology of female erectile organs are neglected in specialist textbooks. In infibulated women, some erectile structures fundamental for orgasm have not been excised. Cultural influence can change the perception of pleasure, as well as social acceptance. Every woman has the right to have sexual health and to feel sexual pleasure for full psychophysical well-being of the person. In accordance with other research, the present study reports that FGM/C women can also have the possibility of reaching an orgasm. Therefore, FGM/C women with sexual dysfunctions can and must be cured; they have the right to have an appropriate sexual therapy.
Vulvar Vestibulitis Syndrome and Estrogen Dose of Oral Contraceptive Pills
Authors: Greenstein Alexander , Ben-Aroya Zahi , Fass Orit , Militscher Idan , Roslik Yelena , Chen Juza , Abramov Liora
Published: October 2007

Introduction

Vulvar vestibulitis syndrome (VVS) is a diverse, multifactorial phenomenon. Its precise etiology is unknown.

Aim

To define the association between oral contraceptive (OC) estrogen dosage and VVS.

Methods

Women diagnosed as having VVS participated in the study.

Main Outcome Measures

Data on type and usage of oral contraceptive pills (OC) were obtained by a questionnaire, and they were compared for the data on OC usage in the general population.

Results

Available commercial data on Israeli women taking OC showed that 51% of them use low-dose estrogen (≤20 µg) OC and 49% use higher-dose estrogen (30–35 µg) OC. Of the 132 women in the study, 86 (65%) used OC: 68 (79%) used low-dose estrogen OC (P <0.002 compared to the general population), while only 18 (21%) used high-dose estrogen OC (P <0.002 compared to the general population).

Conclusion

Significantly more patients who are treated in our clinic for VVS use low-dose estrogen than those who use high-dose estrogen OC.
Nonlinear Dynamic Behavior of a Motorcycle’s Forecarriage During Braking
Authors: Braghin F. , Brembilla M. , Brambilla G. , Pezzola M.
Published: October 2007

An experimental and numerical experience was carried out to investigate the nonlinear dynamic response of the forecarriage of a motorcycle, paying attention to a particular type of vibration that occurs during the braking. In fact, it was found that, in particular conditions of load on the handlebar, braking pressure, speed and temperature, the first flexural mode of the front fork is strongly excited. Thanks to the numerical model, solutions to these undesired vibrations were identified. Experimental tests were carried out modifying the design parameters of the motorcycles and of the braking system as suggested by the numerical model thus verifying that the purposed solutions were effective.
Multiaxis Maglev Positioner With Nanometer Resolution Over Extended Travel Range
Authors: Kim Won-jong , Verma Shobhit
Published: October 2007

This paper presents a novel multiaxis positioner that operates on the magnetic-levitation (maglev) principle. This maglev stage is capable of positioning at the resolution of a few nanometers over a planar travel range of several millimeters. A novel actuation scheme was developed for the compact design of this stage that enables six-axis force generation with just three permanent magnets. We calculated the forces with electromagnetic analysis over the whole travel range and experimentally verified them with a unit actuator. The single-moving part, namely, the platen, is modeled as a pure mass due to the negligible effect of magnetic spring and damping. There are three laser interferometers and three capacitance sensors to sense the six-axis position/rotation of the platen. A lead-lag compensator was designed and implemented to control each axis. A nonlinear model of the force was developed by electromagnetic analysis, and input current linearization was applied to cancel the nonlinearity of the actuators over the extended travel range. Various experiments were conducted to test positioning and loading capabilities. The 0.267kg single-moving platen can carry and precisely position an additional payload of 2kg. Its potential applications include semiconductor manufacturing, microfabrication and assembly, nanoscale profiling, and nanoindentation.
Modeling and Control of Electrostatically Actuated MEMS in the Presence of Parasitics and Parametric Uncertainties
Authors: Zhu Guchuan , Penet Julien , Saydy Lahcen
Published: October 2007

Due to the compact layout, manufacturing tolerance, modeling errors, and environmental changes, microelectromechanical systems (MEMSs) are subjected to parasitics and parameter variations. In order to better guarantee their stability and a certain level of performance, one must take into account these factors in the design of MEMS control systems. This work presents two robust control laws for a parallel-plate electrostatic microactuator in the presence of uncertainties. The dynamical model of the system, including parallel and serial parasitics, is firstly established and two control schemes, both based on input-to-state stabilization and robust backstepping, are proposed. The stability and the performance of the system using these control schemes are demonstrated through both stability analysis and numerical simulation.
Disturbance Attenuation Using a dc Motor for Radial Force Actuation in a Rotordynamic System
Authors: Leuschke Rainer , Fabien Brian C.
Published: October 2007

This paper presents a technique for attenuating the external disturbances acting on the rotor of a prototype flywheel energy storage device. The approach uses a three-phase axial flux brushless dc motor to simultaneously produce a torque and a radial force. This is accomplished by using two phases of the motor for torque generation, and one phase to produce the radial force. The paper develops a set of equations that can be used to predict the forces generated by the motor coils. These equations are used to implement a feedback control system to suppress the effects of external excitations. The nonlinear controller requires the velocity measurements and the angular displacement of the flywheel. The controller essentially adds damping to the system, and the constant feedback gains solve an optimization problem that involves a H∞ bound on the disturbance attenuation. The experimental results clearly demonstrate that the dc motor can be used to suppress unwanted radial vibrations due to external disturbances.
Nonlinear Modeling by Interpolation Between Linear Dynamics and Its Application in Control
Authors: Kiriakidis Kiriakos
Published: October 2007

This paper proposes a finite series expansion to approximate general nonlinear dynamics models to arbitrary accuracy. The method produces an approximation of nonlinear dynamics in the form of an aggregate of linear models, weighted by unimodal basis functions, and results in a linear growth bound on the approximation error. Furthermore, this paper demonstrates that the proposed approximation satisfies the modeling assumptions for analysis based on linear matrix inequalities and hence widens the applicability of these techniques to the area of nonlinear control.
LS-SVM Modeling Based Inverse Controller With Uncertainty Compensation
Authors: Yuan Xiaofang , Wang Yaonan
Published: October 2007

Least squares support vector machine (LS-SVM) modeling based inverse controller (IC) is presented for excitation control of synchronous generator. This IC strategy design includes two main parts: inverse control law and uncertainty compensation. The inverse control law, designed for the control of plant dynamics, is derived directly based on Taylor expansion and it is implemented using LS-SVM modeling. In addition, a robustness filter in the feedback structure, designed for plant disturbance, is employed as uncertainty compensation. The robust stability of the proposed controller is analyzed based on Lyapunov function. Simulations demonstrate the effectiveness of the IC strategy for excitation control.
Albert Einstein and Mościcki's Patent Application
Authors: Gołab-Meyer Zofia
Published: October 2007

Much was said and written during the 2005 World Year of Physics about Einstein's work in the Bern, Switzerland, Patent Office (Fig. 1). He took the post (Technical Expert 3rd Class) there after completing his studies at the Zurich Polytechnic (later called ETH) in 1900 and being unsuccessful in his attempts to obtain a university position. However, little seems to be known of the patent applications he examined during his five years at the office in Bern. This paper discusses one of those applications—one that was submitted by a rather remarkable individual.
Aliens or the SR-71 Blackbird?
Authors: Ruiz Michael J.
Published: October 2007

Unidentified flying objects (UFOs) capture the interest of our students and the general public.1,2 Here is a UFO story I tell my students to illustrate the workings of science. Science, at its most fundamental level, is observation and an attempt to analyze what is observed. But what happens when an observation cannot be explained with the available knowledge at the time? What do we do? The UFO sighting of my story could not be explained until disclosure of a top-secret military aircraft, the SR-71, also known as the “Blackbird.”
Retaking a Test Online
Authors: Kortemeyer Gerd , Bauer Wolfgang , Benenson Walter , Kashy Edwin
Published: October 2007

Tests and midterms given during the running semester are, in the mindset of most educators, located somewhere between formative and summative assessment: more serious than homework, but still—as opposed to the final exam—mostly a learning opportunity. In the mindset of most learners, however, these venues are purely summative—they “flunked” or “did well” on a test, but mostly, they got it over with. Few students come to office hours to understand what they did wrong. If they had a bad day, they have no second chance to correct their mistakes, but more importantly, they do not receive any immediate incentive or reward to address detected deficiencies, or for deeper learning, reviewing, and understanding of the material after the test is over.
Science Icebreaker Activities: An Example from Gravitational Wave Astronomy
Authors: Larson Michelle B. , Rubbo Louis J. , Zaleski Kristina D. , Larson Shane L.
Published: October 2007

At the beginning of a class, workshop, or meeting, an icebreaker activity is often used to help loosen up the group and get everyone talking. When used as a precursor to group learning, the icebreaker fosters communication so later activities function more smoothly. Science-based icebreaker activities serve the purpose of a traditional icebreaker, while also introducing science content to the audience. The content of the icebreaker may or may not be related to the topic of the upcoming class or meeting. Either way, the activity provides a way to get people talking while the participants simultaneously learn something new and interesting.
Doppler Football
Authors: Ruiz Michael J. , Abee Jeremy
Published: October 2007

In this paper we present a design for a Doppler football. The classic Doppler ball uses a piezo buzzer and 9-V battery inside a foam ball. In our Doppler football, the sound level is enhanced by directing the 2.8-kHz tone of the buzzer through a hollow cylinder to one end of the football, with an on-off switch placed at the other end. We discuss our device within the historical context of Doppler demonstrations that have evolved over the many decades since Doppler's discovery.
The Levitating Buddha: Constructing a Realistic Cylindrical Mirror Pseudo Image
Authors: Caussat María Alicia , Rabal Héctor , Muramatsu Mikiya
Published: October 2007

There are several interesting experiments involving image formation that can be easily implemented using mirrored foil, a very inexpensive material. When the foil is somewhat bent by holding its opposite edges and slightly pulling them together, cylindrical surfaces are generated. They behave as cylindrical mirrors, and circular or elliptical cross sections can be made. A project that can be easily built with the mirror foil is the generation of a pseudo image that is so compelling in its apparent reality that it can easily be taken to be the object itself.
Dare You Play It Safe?
Authors: Gluck Paul , Yaron Oded , Harmatz Margalit
Published: October 2007

We should like to present here the winning entry in last year's “cracking the safe” nationwide competition for Israeli high schools, organized annually by the youth wing of the Weizmann Institute of Science in Rehovoth.
The Sandbag Collision
Authors: Zou Xueli
Published: October 2007

As physics teachers, we all know that many introductory physics students have difficulties in understanding conservation of energy during inelastic collisions where the difficult-to-visualize concept of internal energy is involved. An interesting approach using a pair of model carts1,2 has been developed to help students visualize and understand the concept of internal thermal energy involved during an inelastic collision. This paper will illustrate a sandbag collision experiment that uses visible deformation of the sandbag to help students visualize where the kinetic energy goes during an inelastic collision. This experiment problem (as shown in Fig. 1) can be broken into three small subparts: 1) The pendulum bob swings down until right before hitting the box—a conservation of energy problem; 2) The bob collides with the box—a conservation of momentum problem; 3) The box slides on the table until it comes to a stop—a conservation of energy problem or a dynamics problem.
Fun with Automobile Springs
Authors: Fritsch Klaus
Published: October 2007

Simple measurements on car suspension systems and their analysis can raise student interest in the elementary discussion of the behavior of springs in oscillating systems. To understand these complicated oscillating systems and to interpret measurements properly, models may be used. Students find out how to make approximations and extract useful information from marginal data using common sense, basic physics, and simple software tools. Basic experiments on a physical model of a car suspension and on a passenger car, as well as the analysis of the data, will be presented. In particular, a value of the bounce mode frequency of a car was obtained using several approaches.
The First Three Minutes … of Class
Authors: Slater Timothy F.
Published: October 2007

Editor's Note: The importance of setting the tone from the beginning of class cannot be emphasized enough. Dr. Tim Slater, a frequent contributor to this column, shares some strategies to get students actively engaged in the lesson quickly using discrepant events and bell work tasks.
Shoulder joint kinetics of the elite wheelchair tennis serve
Authors: Reid Machar , Elliott Bruce , Alderson Jacque
Published: October 2007

Background:

The shoulder is a key joint in wheelchair locomotion and commonly implicated in injury among virtually all wheelchair populations. In tennis, quantification of the shoulder joint kinetics that characterise the wheelchair serve could enhance injury prevention and rehabilitation practices as well as assist coaches evaluate the efficacy of their current technical instruction.

Methods:

A 12-camera, 250 Hz Vicon motion analysis system (Oxford Metrics Inc., UK) recorded the 3D flat (WFS) and kick serve (WKS) motions of two male top 30-ranked international wheelchair players. Mechanical comparisons between wheelchair players, as well as to the previously captured data of 12 high-performance able-bodied players executing the same types of serves, were undertaken.

Results:

Without the benefit of a propulsive leg action, wheelchair players developed lower peak absolute (∼32 m/s) and horizontal (∼28 m/s) pre-impact racquet velocities than able-bodied players (∼42 m/s, ∼38 m/s). Wheelchair serve tactics nevertheless necessitated that higher pre-impact horizontal and right lateral racquet velocities characterised the WFS (∼29 m/s, WKS: ∼26 m/s) and WKS (∼4 m/s, WFS: ∼11 m/s) respectively. The shoulder joint kinetics that contributed to the differential racquet velocity profiles were mostly developed independent of wheelchair serve type, but varied with and were likely related to the level and severity of spinal cord injury of the individual players.

Conclusions:

Compared with able-bodied players, wheelchair players experienced matching pre- and post-impact shoulder joint loads, such that wheelchair and able-bodied playing populations appear subject to similar shoulder joint injury risk.
Stress injury of the lunate in tennis players: a case series and related biomechanical considerations
Authors: Maquirriain Javier , Ghisi Juan P
Published: October 2007

Objective:

To investigate clinical and imaging differential diagnosis and tennis stroke biomechanics potentially involved in lunate stress injury pathogenesis.

Methods:

The present report describes five competitive tennis players with overuse-related dorsal wrist pain assessed by magnetic resonance imaging.

Results:

Magnetic resonance imaging revealed the presence of lunate stress injury. All players were treated conservatively, with symptom resolution and complete functional recovery achieved at 14 weeks.

Conclusions:

Lunate stress injuries should be considered in the differential diagnosis of overuse-related dorsal wrist pain in tennis players.
Calcifications in the cuff: take it or leave it?
Authors: Hofstee Dirk-Jan , Gosens Taco , Bonnet Michel , De Waal Malefijt Jan
Published: October 2007

Objectives:

The aim of this study was to evaluate whether removing the calcifications in the rotator cuff tendons during surgical subacromial decompression improves outcome in patients with calcific tendonitis.

Methods:

Two groups of 20 patients with a subacromial impingement syndrome and cuff calcifications were operated on. In group A, patients had an anterolateral acromioplasty according to Neer with excision of calcifications. In group B, the same procedure was performed without additional excision of calcifications. After a minimum follow-up of 3 years the patients were assessed with the disabilities of arm, shoulder and hand score (DASH), the visual analogue scale (VAS) for pain, measurements of range of motion (ROM) in all planes, and satisfaction with treatment.

Results:

The results for the DASH score, ROM, VAS and satisfaction with treatement showed no significant difference between the two groups.

Conclusion:

The results of our study suggest that removal of calcific deposits with anterolateral acromioplasty does not influence patient outcome. Further prospective studies are needed to determine the optimal surgical treatment for calcific tendonitis.
Anthropometric characteristics, body composition and somatotype of elite junior tennis players
Authors: Sánchez-Muñoz Cristóbal , Sanz David , Zabala Mikel
Published: October 2007

Objectives:

The aims of this study were to describe the anthropometric characteristics, body composition and somatotype of elite male and female junior tennis players, to compare the anthropometric data, body composition and somatotype of the first 12 elite junior tennis players on the ranking with the lower ranked players, and to establish an anthropometric profile chart for elite junior tennis players.

Methods:

A total of 123 (57 males and 66 females) elite junior tennis players participated in this study. The athletes were divided into two groups, the first 12 and the lower ranked players, according to gender. A total of 17 anthropometric variables were recorded of each subject.

Results:

There were no significant differences in height and weight between the first 12 and the lower ranked boys, while the first 12 girls were significantly taller than the lower ranked girls (p = 0.009). Significant differences were found for humeral and femoral breadths between the first 12 and the lower ranked girls (p = 0.000; p = 0.004, respectively). The mean (SD) somatotype of elite male junior tennis players could be defined as ectomesomorphic (2.4 (0.7), 5.2 (0.8), 2.9 (0.7)) and the mean (SD) somatotype of elite female junior tennis players evaluated could be defined as endomesomorphic (3.8 (0.9), 4.6 (1.0), 2.4 (1.0)). No significant differences were found in somatotype components between the first 12 and the lower ranked players of both genders.

Conclusions:

When comparing the first 12 and the lower ranked elite junior tennis players of both genders, no significant differences were observed in any measured item for the boys. By contrast, significant differences were observed in height and humeral and femoral breadths between the first 12 and the lower ranked girls, whereby the first 12 were taller and had wider humeral and femoral breadths than the lower ranked players. These differences could influence the playing style of junior female players.
Optimal skyline corridor spacing for partial cutting in second-growth stands of coastal British Columbia
Authors: Howard Andrew F. , Rutherford Dag , Young G. Glen
Published: October 2007

This paper presents the findings of a study on the economically optimal spacing of skyline corridors in partial cuts in second-growth stands of British Columbia. The mathematical basis for optimal spacing of corridors is presented for rectangular settings when trees are felled in a herring-bone pattern to facilitate yarding. The model is used in a case study where optimal spacing is compared with actual spacing for two yarding systems observed in the field. The results indicate that significant cost savings are possible from spacing skyline corridors at the optimal distance compared with conventional spacing used by the logging contractors.
Inheritance of mitochondrial DNA in interspecific crosses of Piceaglauca and Piceaomorika
Authors: David Andrew J. , Keathley Daniel E.
Published: October 2007

Fifteen interspecific hybrids of Serbian spruce (Piceaomorika (Panc) Purkyne) and white spruce (Piceaglauca (Moench) Voss) representing five separate crosses, including reciprocals, were used to demonstrate maternal inheritance of mitochondrial DNA. Total DNA was extracted from foliage samples of Serbian spruce (S), white spruce (W), and both S(♂) × W(♀) and W(♂) × S(♀) hybrids, digested and probed with one of two maize mitochondrial genes, ATPaseα or COXII. ATPaseα generated diagnostic Serbian and white spruce genotypes for all five enzymes tested, while COXII differentiated between the two species for four of five enzymes. Maternal inheritance was indicated in all hybrids for every diagnostic enzyme–probe combination. No paternal or nonparental bands were detected. A dilution experiment indicated that the Serbian and white spruce mitochondrial DNA restriction fragment length polymorphisms could be detected in as little as 60 and 500 ng of total DNA, respectively. It appears that the mechanism that controls the inheritance of mitochondria in Picea is still functional in wide interspecific crosses.
Hybridization between Picearubens and Piceamariana: differences observed between montane and coastal island populations
Authors: Bobola Michael S. , Hillenberg Kimberly A. , Gendreau Steve B. , Eckert Robert T. , Klein Anita S. , Stapelfeldt Karen
Published: October 2007

Foliage was collected from natural stands of montane and island red spruce (Picearubens Sarg.) and black spruce (Piceamariana (Mill.) BSP) to examine within- and among-population genetic variation. Samples were scored for frequencies of nuclear ribosomal DNA (rDNA) alleles, and mitochondrial and chloroplast haplotypes. Samples were classified as red spruce, black spruce, or hybrid using two molecular methods: a three-character discriminant function based on molecular markers or a three-character molecular index. These results were found to be highly congruent with classification based upon a discriminant function using morphological traits. Among montane populations, hybridization and introgression between red and black spruce did not appear to be a major factor in the observed patterns of variation on elevational transects on Mount Washington and Mount Lafayette, N.H. However, extensive hybridization and introgression were detected among populations on Isle au Haut, Maine. The Mount Lafayette population displayed low variation in rDNA alleles compared with populations on Mount Washington and a range-wide provenance test in Stewartstown, N.H.
Evaluation of fungicides for control of Sphaeropsis shoot blight of red pine nursery seedlings
Authors: Stanosz G.R. , Smith D.R.
Published: October 2007

A nursery study was conducted to evaluate possible chemical alternatives to the fungicide benomyl for control of shoot blight caused by Sphaeropsissapinea (Fr.: Fr.) Dyko & Sutton in Sutton on red pine (Pinusresinosa Ait.). Replicated plots of seedlings in their first or second growing seasons were treated either weekly or biweekly with one of the following materials (or combinations): benomyl; thiophanate-methyl; mancozeb; thiophanate-methyl + mancozeb; chlorothalonil; copper; myclobutanil; myclobutanil + thiophanate-methyl; water (control). Plots were located in three complete blocks at increasing distances from an inoculum source, diseased trees in a red pine windbreak. Percentages of seedlings affected by shoot blight were determined by examination in late fall. Analyses of variance indicated significant treatment and block effects (p < 0.0001) on disease incidence. The most effective materials applied either weekly or biweekly to seedlings of either age were the systemics benomyl and thiophanate-methyl, and the protectant chlorothalonil. In spite of fungicide application, incidence of disease was generally much higher in plots within the block closest to the red pine windbreak and lower in plots farther from this windbreak. Results confirm the desirability of integrating chemical and cultural practices for control of Sphaeropsis shoot blight in conifer nurseries.
Development of random amplified polymorphic DNA markers for genetic mapping in Pacific yew (Taxusbrevifolia)
Authors: Göçmen B. , Kaya Z. , Jermstad K.D. , Neale D.B.
Published: October 2007

A genetic linkage map was constructed for Pacific yew (Taxusbrevifolia Nutt.) based on random amplified polymorphic DNA (RAPD) markers. A series of optimization experiments were conducted to develop a highly repeatable protocol for Pacific yew. In these experiments, a high MgCl2 concentration (5.5 mM) together with a low primer concentration (0.2 μm) in the polymerase chain reaction (PCR) mixture yielded the best amplification products. PCR amplification products were further improved by treating the template DNAs with RNase. Experiments showed that bovine serum albumine had the same effect as RNase on PCR amplification. The segregating mapping population consisted of 39 haploid megagametophytes from a single mother tree. DNA extracted from a subset of 6 megagametophytes was screened with 345 ten-base oligonucleotide primers of arbitrary sequence. Of the screened primers, 28% revealed at least one polymorphic locus. Eighty-six of these primers revealed at least one polymorphic locus and were used with the entire set of megagametophyte DNAs. One-hundred-two loci were scored and segregated in the expected 1:1 ratio (1.19 locus per primer). Linkage analysis was conducted using MAPMAKER. Forty-one of 102 markers were distributed into 17 linkage groups and covered 305.8 centimorgans. The remaining 61 unlinked markers should be assigned to linkage groups as more markers are added to the map.
Seed mass effects on germination and growth of diverse European Scots pine populations
Authors: Reich P.B. , Oleksyn J. , Tjoelker M.G.
Published: October 2007

Seedlings of 24 European Scots pine (Pinussylvestris L.) populations were grown in controlled environment chambers under simulated photoperiodic conditions of 50 and 60°N latitude to evaluate the effect of seed mass on germination and seedling growth characteristics. Seeds of each population were classified into 1-mg mass classes, and the four classes per population with the highest frequencies were used. Photoperiod had minimal influence on seed mass effects. Overall, seed mass was positively related to the number of cotyledons and hypocotyl height. Populations differed significantly in seed mass effect on biomass. In northern populations (55–61°N), dry mass at the end of the first growing season was little affected by seed mass. However, dry mass in 9 of 15 central populations (54–48°N) and all southern (<45°N) populations correlated positively with seed mass. Relative growth rate was not related to seed mass within or across populations, and thus early growth is largely determined by seed mass. Relative growth rate also did not differ among populations, except for a geographically isolated Turkish population with the highest seed mass and lowest relative growth rate. After one growing season, height was positively correlated (r2 > 0.6) with seed mass in 15 populations. To check the duration of seed mass effects, height growth of 1- to 7-year-old field experiments established with the same seed lots were compared. Seed mass effects on height were strongest for 1-year-old seedlings and declined or disappeared by the age of 5–7 years among central and southern populations, but remained stable over that time in northern populations.
Heritabilities and additive genetic coefficients of variation in forest trees
Authors: Cornelius Jonathan
Published: October 2007

Estimates of individual-tree narrow-sense heritability and additive genetic coefficient of variation of seven traits of forest trees were compiled from 67 published papers. Distributions of the values for each trait were characterized and compared by calculating medians and running Kolmogorov–Smirnov and Wilcoxon signed-rank tests. Generalizations are possible about at least some of the traits examined. Heritability of wood specific gravity was almost always above 0.3 (median 0.48). Heritabilities for other traits tended to be low: medians ranged from 0.185 to 0.26, and individual values generally ranged from 0.1 to 0.4. Evidence that heritabilities of form traits tend to be higher than those of growth traits was weak. The analysis of additive genetic coefficients of variation suggested that specific gravity tends to have lower values than other traits (median 5.1%), while height and diameter (medians 8.5 and 8.6%, respectively) had lower values than straightness (median 11.65%). Individual-tree volume showed the highest levels of additive genetic coefficient of variation (median 20.3%). The levels of additive genetic variation and heritabilities suggest that reasonable levels of genetic gain can be achieved by screening relatively low numbers of trees.
Eastern cottonwood clonal mixing study: predicted diameter distributions
Authors: Knowe Steven A. , Foster G. Sam , Rousseau Randall J. , Nance Warren L.
Published: October 2007

A parameter recovery procedure for the Weibull distribution function was modified to incorporate monocultures and mixtures of eastern cottonwood (Populusdeltoides Bartr.) clones planted in Mississippi and Kentucky. Components of the system included functions to predict stand-level basal area and four percentiles (0th, 25th, 50th, and 95th) of the cumulative diameter distribution. Basal area was predicted as a function of surviving number of trees, dominant height, age, planting location, and the proportion of each clone planted. Clonal proportions, which accounted for 3.6% of the variation in observed basal area, were more important than differences in planting locations, which accounted for 3.0% of the variation. Interactions between clones in mixtures were not significant (p = 0.5676), but some cases of both over- and under-compensation appeared to be developing. Percentiles of the cumulative diameter distribution were predicted as functions of quadratic mean diameter, and therefore included indirect effects of both genetic and planting site differences. Only the minimum diameter (D0) was directly affected by proportions of clones planted. Most of the monocultures and mixtures of clones had smaller minimum diameters than expected for a given value of quadratic mean diameter. The predicted quadratic mean diameter and percentiles were used to recover parameters of the Weibull distribution such that the predicted diameter distribution has the same quadratic mean diameter as obtained from the stand basal area model. The predicted distributions indicated that a common stand-level model was not sufficient for accounting for variations in diameter distributions of eastern cottonwood clones. As a result of the differences in diameter distributions, monocultures and mixtures of the Texas clones appeared to have less volume and greater stand variance than the Mississippi clones.
More on estimating the statistical significance of cross-dating positions for "floating" tree-ring series
Authors: Yamaguchi David K.
Published: October 2007

Tabulated Student's t-values and climatic insensitivity among inner tree-ring widths can bias estimates of statistical significance for cross correlations relating "floating" and master tree-ring series. These biases can be removed by (i) directly computing significance levels for cross-correlation coefficients at dating positions and (ii) deleting insensitive inner rings from a dated floating sample before final correlation analysis. The number of early rings to delete can be determined from plots of cross-correlation coefficients linking a dated floating series of artificially decreasing length with a master series. These modifications improve the precision of Yamaguchi and Allen's approach (D.K. Yamaguchi and G.L. Allen. 1992. Can. J. For. Res. 22: 1215–1221) for estimating significance.
Effects of wetness duration, temperature, and light on infection of black spruce seedlings by Botrytiscinerea
Authors: Zhang P.G. , Sutton J.C.
Published: October 2007

Postinoculation wetness duration, temperature, and light conditions were investigated in relation.to infection of container-grown seedlings of black spruce (Piceamariana (Mill.) B.S.P) by Botrytiscinerea Pers.:Fr. Seedlings were predisposed to the pathogen by treatment at 35 ± 1 °C in darkness for 4 days immediately before inoculation, and infection was assessed indirectly by estimating sporulation incidence of the pathogen on 6-mm segments of the needles. Sporulation incidence was zero when the temperature during 32 h of the postinoculation wetness was 1, 4, and 36 °C, about 7–10% at 12 °C, 40–47% at 28 °C, and maximal (44–56%) at 20 °C. Sporulation incidence was zero at all tested temperatures when wetness duration was <8–12 h, but increased progressively when the wetness period was increased from 12 to 32 h. Light and darkness during the wetness period did not significantly affect sporulation incidence. Logistic regression models were developed that adequately described sporulation incidence, and by inference, infection incidence, as functions of the postinoculation wetness period and temperature, and were validated using sets of independent data.
Juvenile–mature relationships for wood density in Pinustaeda
Authors: Williams Claire G. , Megraw Robert A.
Published: October 2007

Open-pollinated seeds were collected from loblolly pine (Pinustaeda L.) selections made in natural stands in eastern North Carolina, then planted in a short-term, closely spaced test and in a conventional genetic test. Wood density measurements from seedlings, from older trees, and from parents aged 40–75 years old were used to estimate the genetic covariance structure between juvenile and mature wood. These data were also used to determine if the genetic relationship between juvenile and mature wood varied with the estimation method used or with the fertilizer and irrigation treatments in the short-term test. Age–age relationships were moderately to highly positive and these results were corroborative using several methods: parent–offspring regression and coefficient of genetic prediction, half-sib analyses, and graphical use of type I selection mistakes. Strong age–age relationships (rg = 0.76 to 0.90) were expressed between juvenile wood in the short-term test and older-tree wood density in the genetic test. Moderate to high heritabilities (h2 = 0.55–0.76) were estimated for juvenile wood in short-term tests. The latter estimates tended to be higher than heritability estimates based on parent–offspring regression (h2 = 0.23–0.25). There was negligible family × treatment interaction due to rank change between short-term testing treatments. Height and specific gravity expressed a slight positive correlation at all ages.
Influence of Mount St. Helens ash on litter decomposition. I. Pacific silver fir needle decomposition in the ash-fall zone
Authors: Edmonds Robert L. , Erickson Heather E.
Published: October 2007

The influence of air-fall tephra (ash) from the May 18 1980 eruption of Mount St. Helens on decomposition of Pacific silver fir (Abiesamabilis (Dougl.) Forbes) needles was studied at two sites along the ash-fall plume northeast of the mountain, Elk Pass and Chambers Lake (20 and 60 km from the crater, respectively). Ash depths beneath the canopy of the old-growth stands at Elk Pass and Chambers Lake were 18 and 5 cm, respectively. Objectives of the study were to determine: (i) the decomposition rates of needles on the ash surface, buried under ash, and in control plots with ash removed; (ii) the effect of site on decomposition rates; and (iii) the influence of ash on forest floor temperature, moisture, and oxygen levels. Ash had considerable influence on litter decomposition. After 3 years, needles buried under ash had faster decomposition rates at both sites (k = 0.34 and 0.29/year at Elk Pass and Chambers Lake, respectively) than needles on the ash surface or in cleared control plots. There was a trend for needles on the ash surface to have slower decomposition (k = 0.18–0.23/year) than needles on control plots (k = 0.22–0.28/year). Site had little influence on buried needle decomposition; rates at Elk Pass and Chambers Lake were not significantly different, despite differences in ash texture and depth. Ash apparently did not reduce oxygen levels enough to reduce decomposition, but instead increased decomposition by influencing substrate moisture and temperature. Fastest decomposition occurred under the ash where conditions were moist and cool; slowest decomposition occurred on the ash surface where conditions were drier and warmer.
Effects of partial bark removal on the growth of Pacific yew
Authors: Minore Don , Weatherly Howard G.
Published: October 2007

Whole-tree harvest of Pacific yew (Taxusbrevifolia Nutt.) to provide bark for production of the new anticancer drug taxol may adversely affect stand structure where yews provide thermal cover, browse, or riparian benefits. Harvesting only a portion of the bark on standing trees would maintain existing stand structure if the affected trees continued to grow, but partial bark removal seldom has been applied because its long-term effects are unknown. We measured 121 yews that had been scarred by windthrow or logging damage 3–92 years ago and found that their growth did not differ significantly from the growth of nearby unscarred yews. Radial growth of the scarred trees was strongly correlated with growth before scarring; it was slightly associated with overstory canopy density, elevation, and the amount of bark removed. Partial bark removal from one side of the tree probably will not seriously affect the growth of Pacific yew if less than 50% of the bark is removed.