bluuebunny/crossref_metadata_2025 huggingface dataset:
Does Acupuncture Contribute to the Treatment of Chronic Shoulder Pain (Csp)
Authors: Molsberger AF
Published: April 2009

Objective

Response of Chinese acupuncture compared to conservative orthopaedic treatment and unspecific needling in pain treatment on CSP.

Design

Prospective, randomized controlled trial with three blinded parallel groups; follow up three months.

Setting

Outpatients of 26 orthopaedists, who have attended a 140 hours training course on acupuncture.

Patients

Four hundred and twenty seven out-patients with a history of CSP ≥ six weeks, VAS ≥ 50 mm were selected; three random groups, six weeks treatment. 308 patients reported after three months follow up. Two strata: age 25–45 and age 46–65.

Interventions

Group 1: VAP: 15 treatments of verum acupuncture (VAP). Group 2: SHM: 15 treatments of non-specific needling, sham acupuncture (SHM). Group 3: COT: conventional conservative orthopaedic treatment (COT). Patients were blinded to allocation between verum and sham acupuncture.

Main Outcome Measures

Primary endpoint: pain reduction ≥ 50% on VAS three months after the end of the treatment protocol. Secondary endpoints: global assessments on a 4-score scale directly after the end of the treatment protocol.

Results

The results after three months follow up are: Highly significant effect of CAP over SHM and COT in the whole sample (P<0.0001) and in Stratum1 (P<0.001) and Stratum2 (P<0.001).

Conclusions

Acupuncture is an important supplement in the management of CSP. BMBF grant: 01KT9411/9
Neurogenic Pruritus: Treatment by Acupuncture
Authors: Stellon AJ
Published: April 2009

Introduction

Notalgia paraesthetica is a condition associated with itching, and unassociated with a rash, that affects a segment of the body innervated by T2-T6 dorsal spinal nerves. It is believed to be a type of neuropathy. This single-handed practice reports one such case. It also describes a further eight cases of “neurogenic” pruritus which share similar characteristics to this condition but are in segments of the body innervated by cervical and lumbar spinal nerves. Traditional acupuncture has been described to help with skin conditions and this study was performed to see if it was successful in this type of pruritus.

Patients and Methods

Over a nine-year period in a practice with an average list size of 2000 patients, nine patients aged 41 to 79 years presenting with segmental itching were identified. Other causes of pruritus were excluded by clinical examination, as well as by haematological and biochemical tests. Drug induced causes were also excluded. Duration of pruritus was six weeks (range 4 – 52 weeks). In eight patients itching was restricted to dermatomes innervated by the spinal nerves of the cervical spine, in two by the dorsal spine and in two by the lumbar spine. In three patients pruritus occurred in dermatomes innervated by two separate areas of the spine. Clinical examination revealed restricted cervical or lumbar movements in seven patients. Paravertebral tenderness and/or spasm of the paravertebral muscles was found in the areas of pruritus in seven patients. Skin changes associated with sympathetic nerve over-activity were noted in five patients. Six of the nine patients had x-ray evidence of degeneration of the spine.

Results

All nine patients were treated by deep intramuscular stimulation of the paravertebral muscles in the dermatomes affected by pruritus. In total a median of three treatments (range 2 – 5) was required to resolve the pruritus. Recurrence of symptoms occurred in four patients within 8 to 12 months of their last treatment over a period of follow-up of 0.5 – 9 years (median one year). Repeat acupuncture treatment resolved the pruritus.

Discussion

The term neurogenic pruritus describes and encompasses all conditions associated with segmental itching unassociated with a rash. The clinical signs of this condition are suggestive of an early neuropathy as a result of a degenerative condition of the spine. This is the first report of symptoms of such a condition being treated successfully by acupuncture.
No Effect of Chinese Acupuncture on Isocapnic Hyperventilation with Cold Air in Asthmatics, Measured with Impulse Oscillometry
Authors: Malmström Monica , Ahlner Johan , Carlsson Christer , Schmekel Birgitta
Published: April 2009

The cost to society and the individual of treating asthma has been increasing in developed countries. This has given rise to studies of the efficacy of complementary treatments. The aim of this study was to evaluate the efficacy of traditional Chinese Acupuncture in patients with mild asthma. The method used for evaluation of efficacy was total airway resistance at 5Hz (R5) as measured by impulse oscillometry (IOS) – a forced oscillation technique, at baseline and after a bronchial challenge with voluntary isocapnic hyperventilation of cold air (IHCA). The study was a parallel group randomised placebo controlled trial with evaluator blinding. Twenty-seven asthmatics were recruited and 24 completed the study, 10 of them received acupuncture and 14 received a placebo treatment (mock-TENS). Treatment continued for 15 weeks, and efficacy was tested two weeks following the last treatment. Randomisation resulted in female over representation in the acupuncture group, but lung-function and bronchial responsiveness to IHCA were comparable in the two populations before the start of treatment (p>0.05 vs. p>0.05). There were no statistically significant effects of the treatment before (p>0.05) or after IHCA (p>0.05) in either of the groups. The statistical power of the study to show a clinically relevant difference in bronchial responsiveness to IHCA after treatment was near 80%. We conclude that there were no significant effects of traditional Chinese Acupuncture on airway status in our patients with asthma.
An Uncontrolled Pilot Study of Ht7 for ‘stress’
Authors: Chan Joseph , Briscomb Dianne , Waterhouse Esther , Cannaby Anne-Marie
Published: April 2009

Bilateral acupuncture needling at HT7 was an effective method for reducing the rating of ‘psychological stress’ in 16 out of of a group of 17 volunteers (94%), recruited from staff in a hospice. Ratings were made using the Edinburgh Postnatal Depression Scale (EPDS), which was felt to be the most useful scale of those considered, despite not being validated in this population. Four brief acupuncture sessions were performed at weekly intervals. The greatest fall in the EPDS scores was observed within the first two treatments. At the end of the study, there was an average reduction of 44% in the EPDS scores. Further research is needed, including a suitable control group, to determine whether the effect observed in this study was a specific effect of needling at HT7.
Interventions to reduce the frequency of exacerbations of chronic obstructive pulmonary disease
Authors: Black P N , McDonald C F
Published: April 2009

Frequent exacerbations of chronic obstructive pulmonary disease (COPD) are associated with impaired quality of life, and hospital admissions for exacerbations account for a large proportion of the expenditure of COPD. An important objective when treating COPD is to reduce the frequency of exacerbations. Studies published in the last few years have increased our knowledge on how to prevent exacerbations, but a number of questions remain unanswered. Tiotropium, inhaled steroids and long-acting inhaled β agonists reduce the frequency of exacerbations, but further studies are necessary to determine if combining tiotropium with the other inhaled medicines is more effective than using them separately. There is evidence that mucolytics and prophylactic antibiotics reduce exacerbations, but there is uncertainty how these treatments should be used. Both influenza and pneumococcal vaccination are recommended in guidelines, although evidence for the latter remains controversial. Other interventions including oral bacterial extracts and self-management programmes warrant further study.
Programmed cell death and cancer
Authors: Sun Y , Peng Z-L
Published: April 2009

Programmed cell death (PCD) is an important terminal pathway for cells of multicellular organisms, and is involved in a variety of biological events that include morphogenesis, maintenance of tissue homeostasis, and elimination of harmful cells. Dysfunction of PCD leads to various diseases in humans, especially various cancers. Accumulating evidence indicates that PCD is closely related to anti-cancer therapy. Recently, many studies have subdivided PCD into the three categories: apoptosis, autophagy, and programmed necrosis, based on criteria such as morphological alterations, initiating death signal, and the activation of caspases. In this article, we will review the main features and functions of all three types of programmed cell death, focusing on their roles in tumour cells and the relationship of the three types of cell death in anti-cancer therapy.
Health professionals and human rights campaigners: different cultures, shared goals
Authors: Sheather J
Published: April 2009

This article looks at a disagreement that emerged at an international human rights conference between health professionals and human rights activists. The disagreement centred on the scope of the responsibilities of health professionals in relation to potential systemic human rights violations. In this article, the nature of the disagreement that emerged at the conference is explored. It is first situated in relation to a strong shared commitment to the “right of everyone to the highest attainable standard of physical and mental health”—often shortened to “the right to health” as it appears in the International Covenant on Economic, Social and Cultural Rights (ICESCR). Some of the tensions that emerged between the participants are then looked at and some of the causes of apparent disagreement identified. The relevance of human rights to health professionals and their impact on medical practice are discussed. Finally, it is argued that, given the common interests shared by these groups, the misunderstandings are not substantive and that there is real scope for mutual learning and collaboration. Although the conference was in southern Asia, the lessons learnt are applicable anywhere in the world—they are equally as relevant to the UK and Europe as to developing countries in the south.
Risk factors of biliary complications following liver transplantation: retrospective analysis of a single centre
Authors: Yuan D , Wei Y-G , Lin H-M , Li F-Q , Yang M , Liu X-L , Li B , Yan L-N , Zeng Y , Wen T-F , Zhao J-C , Yang J-Y
Published: April 2009

Background

Despite improvements that have been achieved in surgical techniques and organ preservation, biliary complications remain one of the most serious morbidities following liver transplantation. However, factors related to biliary complications after liver transplantation are not completely understood. The objective of this study was to identify retrospectively possible risk factors of biliary complications following liver transplantation.

Methods

Data on 279 patients who underwent liver transplantation between January 1999 and November 2005 were collected retrospectively. Selected variables from preoperative, intraoperative and postoperative data were first analysed using univariate logistic regression. Filtered factors with p<0.1 in the first step were further investigated to identify factors independently associated with biliary complications following liver transplantation.

Results

The overall incidence of biliary complications was 22.6%. Multivariate regression revealed that biliary cirrhosis (p = 0.038), anhepatic phase time (p = 0.04), and incidence of hepatic artery abnormality (p = 0.001) after transplantation were factors that were significantly related to biliary complications. Use of a T tube for biliary reconstruction and living grafts were not associated with biliary complications following liver transplantation.

Conclusion

This study suggests that further technical refinement—namely, shortening the anhepatic phase duration, shielding the hepatic artery, and refining biliary duct reconstruction—can reduce the incidence of biliary complications following liver transplantation.
Ileal MALT lymphoma causing massive gastrointestinal haemorrhage revealed on computed tomography angiography
Authors: Marks D J B , Prodromou A , Silvanto A , Cox A , Pakzad F , Train M , Mitchell I C
Published: April 2009

Primary MALT lymphomas affecting the ileum are rare, and their presentation with massive haemorrhage exceptional. This report describes such a case. The patient presented with melaena and haemodynamic instability, but normal upper gastrointestinal endoscopy. Subsequent imaging with multi-detector row computed tomography angiography both localised the bleeding source to the ileum and identified the underlying tumour, resulting in considerably earlier introduction of appropriate management. The patient made an excellent recovery and remains in remission.
Evaluating the performance of Gulf of Alaska walleye pollock (Theragra chalcogramma) recruitment forecasting models using a Monte Carlo resampling strategy
Authors: Lee Yong-Woo , Megrey Bernard A. , Macklin S. Allen
Published: April 2009

Multiple linear regressions (MLRs), generalized additive models (GAMs), and artificial neural networks (ANNs) were compared as methods to forecast recruitment of Gulf of Alaska walleye pollock ( Theragra chalcogramma ). Each model, based on a conceptual model, was applied to a 41-year time series of recruitment, spawner biomass, and environmental covariates. A subset of the available time series, an in-sample data set consisting of 35 of the 41 data points, was used to fit an environment-dependent recruitment model. Influential covariates were identified through statistical variable selection methods to build the best explanatory recruitment model. An out-of-sample set of six data points was retained for model validation. We tested each model’s ability to forecast recruitment by applying them to an out-of-sample data set. For a more robust evaluation of forecast accuracy, models were tested with Monte Carlo resampling trials. The ANNs outperformed the other techniques during the model fitting process. For forecasting, the ANNs were not statistically different from MLRs or GAMs. The results indicated that more complex models tend to be more susceptible to an overparameterization problem. The procedures described in this study show promise for building and testing recruitment forecasting models for other fish species.
Genetic structure of lake whitefish (Coregonus clupeaformis) in Lake Michigan
Authors: VanDeHey Justin A. , Sloss Brian L. , Peeters Paul J. , Sutton Trent M.
Published: April 2009

Genetic relationships among lake whitefish ( Coregonus clupeaformis ) spawning aggregates in Lake Michigan were assessed and used to predict a stock or management unit (MU) model for the resource. We hypothesized that distinct spawning aggregates represented potential MUs and that differences at molecular markers underlie population differentiation. Genetic stock identification using 11 microsatellite loci indicated the presence of six genetic MUs. Resolved MUs corresponded to geographically proximate spawning aggregates clustering into genetic groups. Within MUs, analyses suggested that all but one delineated MU was a stable grouping (i.e., no between-population differences), with the exception being the Hog Island – Traverse Bay grouping. Elk Rapids was the most genetically divergent population within Lake Michigan. However, low Fstvalues suggested that moderate to high levels of gene flow occur or have occurred in the past between MUs. Significant tests of isolation by distance and low pairwise Fstvalues potentially led to conflicting results between traditional analyses and a Bayesian approach. This data set could provide baseline data from which a comprehensive mixed-stock analysis could be performed, allowing for more efficient and effective management of this economically and socially important resource.
Impacts of episodic acidification on in-stream survival and physiological impairment of Atlantic salmon (Salmo salar) smolts
Authors: McCormick Stephen D. , Keyes Amanda , Nislow Keith H. , Monette Michelle Y.
Published: April 2009

We conducted field studies to determine the levels of acid and aluminum (Al) that affect survival, smolt development, ion homeostasis, and stress in Atlantic salmon ( Salmo salar ) smolts in restoration streams of the Connecticut River in southern Vermont, USA. Fish were held in cages in five streams encompassing a wide range of acid and Al levels for two 6-day intervals during the peak of smolt development in late April and early May. Physiological parameters were unchanged from initial sampling at the hatchery and the high water quality reference site (pH > 7.0, inorganic Al < 12 μg·L–1). Mortality, substantial loss of plasma chloride, and gill Na+/K+-ATPase activity, and elevated gill Al occurred at sites with the lowest pH (5.4–5.6) and highest inorganic Al (50–80 μg·L–1). Moderate loss of plasma chloride, increased plasma cortisol and glucose, and moderately elevated gill Al occurred at less severely impacted sites. Gill Al was a better predictor of integrated physiological impacts than water chemistry alone. The results indicate that Al and low pH under field conditions in some New England streams can cause mortality and impair smolt development in juvenile Atlantic salmon and provide direct evidence that episodic acidification is impacting conservation and recovery of Atlantic salmon in the northeastern USA.
Examination of direct daytime predation by Coregonus artedi on Bythotrephes longimanus in Harp Lake, Ontario, Canada: no evidence for the refuge hypothesis
Authors: Young Joelle D. , Loew Ellis R. , Yan Norman D.
Published: April 2009

Since its introduction to Harp Lake, Ontario, Canada, summer abundance of the cladoceran zooplanktivore Bythotrephes longimanus has fluctuated substantially both among and within years. The principal planktivorous fish in Harp Lake is the cold-water Coregonus artedi (cisco). Previous studies hypothesized that Bythotrephes abundance was affected by the thickness of an ephemeral, dark, daytime refuge from cisco that potentially established at the bottom of the metalimnion. During summer of 2003, we estimated peak daytime refuge thickness by simulating light energy visible to cisco and found it was always negative and did not correlate with Bythotrephes death rates. Direct observations using gill-netting and acoustical methods suggested that cisco had frequent metalimnetic forays. Additionally, including years 2000–2004, the previous correlation between mean Bythotrephes abundance and refuge thickness no longer held. The refuge hypothesis appears to fail, as the amount of metalimnetic illumination was always above the level at which cisco reaction distance to prey is maximal. Selection of Bythotrephes by cisco instead appeared to increase once Bythotrephes became abundant, remaining consistent and nontrivial even after Bythotrephes population declined.
Behavioral responses of juvenile weakfish (Cynoscion regalis) to diel-cycling hypoxia: swimming speed, angular correlation, expected displacement, and effects of hypoxia acclimation
Authors: Brady Damian C. , Targett Timothy E. , Tuzzolino Danielle M.
Published: April 2009

Areas of low flushing and high nutrient loading in shallow estuaries are susceptible to diel-cycling hypoxia and also represent important nursery habitat for juvenile estuary-dependent fishes. Swimming speed, angular correlation, and expected displacement were measured in juvenile weakfish ( Cynoscion regalis ) in response to diel-cycling hypoxia (cycling between 7.0 and 0.4 mg O2·L–1). Saturation-acclimated (7.0 mg O2·L–1) weakfish exhibited an active response by increasing swimming speed (to a maximum at 2.8 mg O2·L–1) and angular correlation (to a maximum at 1.4 mg O2·L–1) as dissolved oxygen (DO) decreased, after which weakfish exhibited a passive response and both swimming speed and angular correlation decreased by ~50% and 70%, respectively, at 0.4 mg O2·L–1. Weakfish acclimated to hypoxia (cycling between 2.0 and 11.0 mg O2·L–1for 10 days) did not vary swimming speed during decreasing DO or DO recovery (increasing DO) and had an overall swimming speed 46% lower than saturation-acclimated weakfish at 7.0 mg O2·L–1. At the end of DO recovery, saturation- and hypoxia-acclimated weakfish had recovered 60% and 80% of their initial swimming speeds, respectively. The relationship between previous hypoxia exposure and behavior may be an important determinant of habitat utilization in estuarine nursery areas impacted by diel-cycling hypoxia.
The evaluation of reference points and stock productivity in the context of alternative indices of stock reproductive potential
Authors: Morgan M. J. , Murua H. , Kraus G. , Lambert Y. , Marteinsdóttir G. , Marshall C. T. , O’Brien L. , Tomkiewicz J.
Published: April 2009

In this study, we explore the impact of four alternative indices of reproductive potential (RP) on perceptions of population productivity for eight fish populations across the North Atlantic. The four indices of RP included increasing biological complexity, adding variation in maturation, sex ratio, and fecundity. Perceptions of stock productivity were greatly affected by the choice of index of RP. Population status relative to reference points, RP per recruit, and projections of population size all varied when alternative indices of RP were used. There was no consistency in which index of RP gave the highest or lowest estimate of population productivity, but rather, this varied depending on how much variation there was in the reproductive biology of the population and the age composition. Estimates of sustainable harvest levels and recovery time for depleted populations can vary greatly depending on the index of RP.
Habitat effects on American lobster (Homarus americanus) movement and density: insights from georeferenced trap arrays, seabed mapping, and tagging
Authors: Geraldi Nathan R. , Wahle Richard A. , Dunnington Michael
Published: April 2009

Understanding the influence of heterogeneous marine landscapes on the movements of benthic megafauna is often hampered by limited spatial resolution and insufficient sample size. Here, we combined the benefits of seabed mapping, georeferenced trap arrays, and conventional tagging methods to quantify the effect of substrate on movements of the American lobster ( Homarus americanus ). In total, 21 848 lobsters were tagged, and movements were tracked among spatially referenced research and commercial traps. We found that lobster densities from diver surveys were highest on rocky habitat, but catch rates in traps were highest on unstructured sediment, resulting in traps on level bottom having a larger effective fishing area than traps on structurally complex habitat. Moreover, tag returns indicated that lobsters initially caught and released on sediment moved farther and faster than those initially caught in traps on rocky substrate. These observations are consistent with previous reports of the existence of a dichotomy of transient and resident lobsters in coastal populations, but the association of movement with habitat type was unknown. Our results indicate that field studies integrating conventional trapping, visual census, and tagging with seabed mapping can efficiently generate high-resolution information on habitat-related behavior of large samples of benthic organisms.
Improved RCI techniques for treating 4fn atoms and ions: Application to Gd IV energies
Authors: Beck D R , Domeier E
Published: April 2009

Relativistic configuration interaction results for energy levels and Landé g-values of Gd IV 4f7 J = 7/2 and Gd IV 4f6 5d J = 5/2, 7/2, 9/2, and energies of 51 new levels are presented. The average error between adjacent energy levels in 4f7 is 4.5%. Significant improvements in computational efficiency and accuracy for the difficult-to-treat 4f7 and 4f6 5d states are introduced, including the use of ab initio determined shifts of diagonal matrix elements (ME) for 4f6 parents, neglecting off-diagonal MEs between quadruple (triple) excitations, and a more systematic treatment of radial convergence.PACS Nos.: 31.15.am, 31.15.vj
Relativity in rotating frames: Riddles and enigmas
Authors: Weber T
Published: April 2009

There is an extensive literature on rotating reference frames dating back to the time Einstein claimed such frames had negative curvature. There still seems to be issues that are not completely settled. In this paper, I will discuss some recent erroneous developments in regards to the Wilson and Wilson experiment of 1913 and the puzzles that people develop to defend their points of view.PACS No.: 03.30.+p
Search for variation of the fundamental constants in atomic, molecular, and nuclear spectra
Authors: Flambaum V V , Dzuba V A
Published: April 2009

The search for variation of the fundamental constants such as the fine-structure constant α (α = e2/hc) and the ratios of fundamental masses (for example, electron-to-proton mass ratio μ = me/mp) is reviewed. Strong emphasis is given to establishing the relationships between the change in the measured frequencies of atomic, molecular, or nuclear transitions and the corresponding change of the fundamental constants. Transitions in which the sensitivity of the frequency change to the variation of the fine-structure constant is strongly enhanced are discussed and most recent experimental results are presented. Most attention is given to the use of atomic, molecular, and nuclear transitions in the study of quasar absorption spectra and in atomic clock experiments.PACS Nos.: 31.25.Eb, 31.25.Jf
Application of B-splines in determining the eigenspectrum of diatomic molecules: robust numerical description of halo-state and Feshbach molecules
Authors: Derevianko A , Luc-Koenig E , Masnou-Seeuws F
Published: April 2009

The B-spline basis-set method is applied to determining the rovibrational eigenspectrum of diatomic molecules. Particular attention is paid to a challenging numerical task of an accurate and efficient description of the vibrational levels near the dissociation limit (halo-state and Feshbach molecules). Advantages of using B-splines are highlighted by comparing the performance of the method with that of the commonly used discrete-variable representation (DVR) approach. Several model cases, including the Morse potential and realistic potentials with 1/R3 and 1/R6 long-range dependence of the internuclear separation are studied. We find that the B-spline method is superior to the DVR approach and it is robust enough to properly describe the Feshbach molecules. The developed numerical method is applied to studying the universal relation of the energy of the last bound state to the scattering length. We illustrate numerically the validity of the quantum-defect-theoretic formulation of such a relation for a 1/R6 potential.PACS Nos.: 31.15.–p,34.50.Cx
Relativistic many-body calculations of excitation energies and transition rates from core-excited states in silverlike ions
Authors: Safronova U I , Safronova A S
Published: April 2009

Energies of [Kr]4d94f2, [Kr]4d94f5l, and [Kr]4d95l5l′ states (with l = s, p, d, f) for Ag-like ions with Z = 50–100 are evaluated to second order in relativistic many-body perturbation theory (RMBPT) starting from a Pd-like Dirac–Fock potential ([Kr]4d10). Second-order Coulomb and Breit–Coulomb interactions are included. Correction for the frequency dependence of the Breit interaction is taken into account in lowest order. The Lamb-shift correction to energies is also included in lowest order. Intrinsic particle–particle–hole contributions to energies are found to be 20–30% of the sum of the one- and two-body contributions. Transition rates and line strengths are calculated for the 4d–4f and 4d–5l electric-dipole (E1) transitions in Ag-like ions with nuclear charge Z = 50–100. RMBPT including the Breit interaction is used to evaluate retarded E1 matrix elements in length and velocity forms. First-order RMBPT is used to obtain intermediate coupling coefficients and second-order RMBPT is used to calculate transition matrix elements. A detailed discussion of the various contributions to the dipole matrix elements and energy levels is given for silverlike tungsten (Z = 74). The transition energies included in the calculation of oscillator strengths and transition rates are from second-order RMBPT. Trends of the transition rates as functions of Z are illustrated graphically for selected transitions. Additionally, we perform calculations of energies and transition rates for Ag-like W by the Hartree–Fock relativistic method (Cowan code) and the Multiconfiguration Relativistic Hebrew University Lawrence Atomic Code (HULLAC code) to compare with results from the RMBPT code. These atomic data are important in modeling of N-shell radiation spectra of heavy ions generated in various collision as well as plasma experiments. The tungsten data are particularly important for fusion application.PACS Nos.: 31.15.A–, 31.15.ag, 31.15.am, 31.15.aj
Two-color modulation transfer spectroscopy
Authors: Galván A Pérez , Sheng D , Orozco L A , Zhao Y
Published: April 2009

We present two-color modulation transfer spectroscopy as a tool for precision studies of atomic properties of excited states. The bi-colored technique addresses a narrow set of velocity groups of a thermal atomic vapour using a two-step transition to “burn a hole” in the velocity distribution. The resulting spectrum presents sub-Doppler linewidths, good signal-to-noise ratio and the trademark sidebands that work as an {in situ} ruler for the energy spacing between atomic resonances. The spectra obtained can be used for different applications such as measurements of energy splittings or stabilization of laser frequencies to excited atomic transitions.PACS Nos.: 32.10.Fn, 32.30.–r, 42.50.Gy, 42.60.Fc
Effects of height imputation strategies on stand volume estimation
Authors: Garber Sean M. , Temesgen H. , Monleon Vicente J. , Hann David W.
Published: April 2009

Subsampling and subsequent imputation of tree heights can improve the predictive performance of stand volume estimation but may also introduce biases. Using coastal Douglas-fir data from southwest Oregon, USA, the predictive performance of several height imputation strategies for estimating stand volume was evaluated. A subsample of 1–15 trees was randomly selected per stand, and missing heights were imputed using a regional Chapman–Richards function with diameter only and diameter plus stand density measures, fitted using a nonlinear least-squares model (NFEM) and a nonlinear mixed-effects model (NMEM). Missing heights were imputed using the regional height–diameter equation and by adjusting the equation with a correction factor (NFEM) or with predicted random effects (NMEM) to calibrate the height–diameter relationship to each stand. Differences in actual stand volumes, calculated with measured heights, and predicted stand volumes, calculated using measured heights for the subsampled trees and predicted heights for those with missing heights, were used to compare the alternative height imputation methods. Precision and bias were poorest for the regional models, especially NMEM, and best for the adjusted models also using NMEM. Results suggest that a similar subsample of heights (n = 4) is required for precise stand volume estimation as has been reported for height.
A framework for modeling the dynamics of first-order branches and spatial distribution of knots in loblolly pine trees
Authors: Trincado Guillermo , Burkhart Harold E.
Published: April 2009

A stochastic model to simulate the processes of initiation, diameter growth, death, and self-pruning of branches in loblolly pine ( Pinus taeda L.) trees is presented. Information on whorl formation and branch growth was obtained from destructive sampling of whorl sections from 34 trees growing under 10 different initial spacings. Three different components were modeled and hierarchically connected: whorl, branches, and knots. For each new growing season, whorls and branches are assigned stochastically along and around the stem. Thereafter, branch diameter growth is predicted as a function of relative location within the live crown and stem growth. The branch model was linked to an individual-tree growth model, PTAEDA3.1, to simulate the dynamics of first-order branches arising from the main stem. Information on (i) vertical trend of branch diameter along and around the stem, (ii) volume of knots (live and dead portions), and (iii) spatial location, size, and type (live and dead) of knots can be obtained. In its current stage, the framework allows evaluation of the quality of trees and sawlogs produced, inclusion of additional wood properties, and linkage with industrial conversion processes (e.g., sawing simulation). However, further research is needed to obtain data on branch dynamics to validate the overall performance of the model and improve developed submodels.
Ecotypic mode of regional differentiation caused by restricted gene migration: a case in black cottonwood (Populus trichocarpa) along the Pacific Northwest coast
Authors: Xie Chang-Yi , Ying Cheng C. , Yanchuk Alvin D. , Holowachuk Diane L.
Published: April 2009

Genetic differentiation of black cottonwood ( Populus balsamifera subsp. trichocarpa (Torr. & A. Gray ex Hook) Brayshaw) across a “no-cottonwood” belt on the coast of central British Columbia (BC), Canada, was examined using data on 3 year height, severity of infection by Valsa sordida Nitschke and Melampsora occidentalis H. Jacks., and abnormality of leaf flushing. The data were collected in a common-garden test consisting of 180 provenances of 36 drainages ranging from northern BC to Oregon, USA. The results demonstrated an ecotypic mode, north–south regional differentiation. Valsa sordida and M. occidentalis infected 41% and 89%, respectively, of the trees from the northern region, while 66% showed flushing abnormality. In contrast, only 1% and 27% of their southern counterparts were infected by the same diseases, and 1% had abnormal flushing. Trees from the northern region averaged 87% shorter than those from the south. Regional differentiation accounted for the highest amount of variation observed in all traits, with 60% in 3 year height, 34% in V. sordida, 76% in M. occidentalis, and 50% in abnormal leaf flushing. Regression analysis revealed geographic patterns that essentially reflected regional differentiation along the no-cottonwood belt. The species’ distribution biography, ecological characteristics, and life history suggest that restricted gene migration was the main factor responsible for the observed geographic patterns of genetic differentiation.
Visual identification, physical properties, ash composition, and water diffusion of wetwood inGmelina arborea
Authors: Moya Róger , Muñoz Freddy , Jeremic Dragica , Berrocal Alexander
Published: April 2009

Wetwood is commonly reported in temperate species but not so in tropical species. In an old Gmelina arborea Roxb. plantation, wetwood was identified by a darker colour compared with the rest of heartwood; by a higher moisture content (average 182%); and a lower specific gravity (0.34, compared with 0.38 for sapwood and heartwood). Tangential shrinkage was 3.7%, which was significantly higher than that of heartwood and sapwood. Radial shrinkage was not significantly different between wetwood and sapwood, but it was significantly greater (2.6%) in wetwood than in heartwood (1.8%). Wetwood had a significantly higher pH than normal wood, but ash composition was similar to that of normal wood, with the exception of the amounts of iron and potassium. Wetwood and sapwood were less decay resistant than heartwood. Wetwood required less time than heartwood to reach equilibrium moisture content, but more time than sapwood. The tangential and longitudinal diffusion coefficients of wetwood were significantly higher than those of heartwood and lower than those of sapwood. In the radial direction sapwood showed a faster drying rate than wetwood but there was no significant difference between wetwood and heartwood.
Climate response of five oak species in the eastern deciduous forest of the southern Appalachian Mountains, USA
Authors: Speer James H. , Grissino-Mayer Henri D. , Orvis Kenneth H. , Greenberg Cathryn H.
Published: April 2009

The climatic response of trees that occupy closed canopy forests in the eastern United States (US) is important to understanding the possible trajectory these forests may take in response to a warming climate. Our study examined tree rings of 664 trees from five oak species (white ( Quercus alba L.), black ( Quercus velutina Lam.), chestnut ( Quercus prinus L.), northern red ( Quercus rubra L.), scarlet ( Quercus coccinea Münchh.)) from 17 stands in eastern Tennessee, western North Carolina, and northern Georgia to determine their climatic response. We dated the samples using skeleton plots, measured the cores, and compared the site- and regional-level tree-ring chronologies of each separate species with divisional climate data. The oldest trees in each chronology dated back to 203 years for black oak, 299 years for chestnut oak, 171 years for northern red oak, 135 years for scarlet oak, and 291 years for white oak. We successfully developed climate models via multiple regression analyses with statistically significant (P < 0.05) variables representing the Palmer Drought Severity Index and average monthly temperature for most of the site-species chronologies (average R2 = 0.15). All regional climate response models included the Palmer Drought Severity Index from either June or July as the most significant variable in the climate response, suggesting that growing-season drought is the most important factor limiting oak growth in the southeastern US. An increase in temperature and reduction in moisture is likely to reduce their competitiveness in their current locations and force these species to migrate to cooler climates, thereby greatly changing ecosystem health and stability in the southern Appalachians.
Paludification dynamics in the boreal forest of the James Bay Lowlands: effect of time since fire and topography
Authors: Simard Martin , Bernier Pierre Y. , Bergeron Yves , Paré David , Guérine Lakhdar
Published: April 2009

In many northern forest ecosystems, soil organic matter accumulation can lead to paludification and forest productivity losses. Paludification rate is primarily influenced by topography and time elapsed since fire, two factors whose influence is often confounded and whose discrimination would help forest management. This study, which was conducted in the black spruce ( Picea mariana (Mill.) BSP) boreal forest of northwestern Quebec (Canada), aimed to (1) quantify the effect of slope and time since fire on paludification rates, (2) determine whether soil organic layer depth could be estimated by surface variables that can potentially be remotely sensed, and (3) relate the degree of paludification to tree productivity. In this study, soil organic layer depth was used as an estimator of the degree of paludification. Slope and postfire age strongly affected paludification dynamics. Young stands growing on steep slopes had thinner organic layers and lower organic matter accumulation rates compared with young stands growing on flat sites. Black spruce basal area and Sphagnum cover were strong predictors of organic layer depth, potentially allowing mapping of paludification degree across the landscape. Tree productivity was negatively related to organic layer depth (R2= 0.57). The equations developed here can be used to quantify forest productivity decline in stands that are undergoing paludification, as well as potential productivity recovery given appropriate site preparation techniques.
Establishment of natural regeneration under severe browsing pressure from white-tailed deer after group seed-tree cutting with scarification on Anticosti Island
Authors: Beguin Julien , Prévost Marcel , Pothier David , Côté Steeve D.
Published: April 2009

The use of large clearcuts with protection of advance regeneration is inappropriate for regeneration of balsam fir ( Abies balsamea (L.) Mill.) under severe browsing from white-tailed deer ( Odocoileus virginianus (Zimmermann)). However, little is known about the effects of tree-retention methods along with scarification on the establishment of balsam fir in a context of severe herbivory. Consequently, we hypothesized that seed-tree-group cutting in conjunction with soil scarification creates favourable conditions for balsam fir regeneration. In 1998 and 1999 we set up three circular forest groups of different sizes (40, 60, and 80 m in diameter) surrounded by three different intensities of scarification (no treatment, single pass, double pass) in two balsam fir stands on Anticosti Island, Quebec, Canada. Moreover, we used a network of fenced and unfenced regeneration plots to evaluate the impact of white-tailed deer browsing. The results showed that up to 7 years after harvest, seed-tree-group cutting did not improve the establishment of conifer species. Scarification had a negative impact on the abundance of conifer species, whereas white birch ( Betula papyrifera Marshall) density was significantly higher in areas scarified twice than in unscarified areas. Overall, the development of palatable tree species appears unlikely at deer densities >20 individuals/km2.
Does cointegration of prices of North American softwood lumber species imply nearly perfectly substitutable products?
Authors: Shook Steven R. , Plesha Nataliya , Nalle Darek J.
Published: April 2009

This study uses the Engle–Granger cointegration method to examine the correlation relationship among prices of North American softwood lumber species, wood-based panel prices, and US single-family housing starts. The methodology employed is identical to that used by US petitioners in the latest round of the Canada – United States softwood lumber trade dispute, whereby petitioners argued that all North American species of softwood lumber were considered to be nearly perfect substitutes for one another. Tests for nonstationarity using the augmented Dickey–Fuller unit root test, as well as our cointegration results, confirm petitioners’ results. We find evidence of a long-term cointegrating relationship among the prices of North American softwood lumber species. However, we found no clear evidence of nearly perfect substitutability among different North American softwood lumber species. Additional analysis reveals that a long-run equilibrium relationship also exists between North American softwood lumber species and four types of wood-based panel products, as well as US single-family housing starts. Given that the price movements of different wood-based panel products and single-family housing starts are highly correlated with the price movement of North American softwood lumber species, we fail to conclude that North American softwood lumber species can be claimed as nearly perfect substitutes. Furthermore, we find that the petitioners’ analysis is deficient in that it does not account for the fact that cointegration in prices among North American species of softwood lumber can be caused by common demand-side factors, such as residential construction activity.
A comparison of thinning methods in red pine: consequences for stand-level growth and tree diameter
Authors: Bradford John B. , Palik Brian J.
Published: April 2009

Long-term replicated experiments that contrast thinning method (dominant thinning, thinning from below) while controlling stocking level are rare. Stand growth and tree size responses to thinning method can be useful for making decisions to achieve desired objectives, whether these are timber or wildlife habitat related. We examined data from two long-term (>50 year old) silvicultural experiments in red pine to understand how alternative thinning prescriptions influence stand-level basal area, volume, and biomass growth, as well as quadratic mean tree diameter. We found that gross growth in stands treated with dominant thinning was often, although not always, greater than growth in stands treated with thinning from below. However, the differences in growth between thinning methods are smallest at stocking levels and stand ages typical for red pine management. We found that biomass growth increases with dominant thinning were generally less than basal area or volume growth increase. Furthermore, greater gross growth associated with dominant thinning versus thinning from below must be weighed against the significantly smaller average tree sizes that result from repeated dominant thinning.
Seasonal dynamics of the radial increment of Scots pine and Norway spruce in the southern and middle boreal zones in Finland
Authors: Henttonen Helena M. , Mäkinen Harri , Nöjd Pekka
Published: April 2009

In the Finnish National Forest Inventory thousands of trees are cored every year. Based on the increment cores we assessed the progress of the radial increment in Scots pine ( Pinus sylvestris L.) and Norway spruce ( Picea abies (L.) Karst.) during the growing season. Data for 18 and 15 years were available from the southern and middle boreal zones, respectively. No major differences were found in the progress of the radial increment between either tree species or vegetation zones. In both zones, the radial increment began at approximately the same time, in late May or early June. On average, half of the annual radial increment was completed in early July, and ceased in late July or early August. However, there was large variation among years in the progress of the radial increment. On average, the radial-increment period (10%–90% of the total increment) was 41–59 days depending on tree species and region. The increment period was slightly shorter in the middle boreal zone, as increment ended 5–11 days later in the southern boreal zone. The variation of annual radial-increment indices was related to the dates of increment onset and cessation. However, increment-period length was more closely related to the differences in increment indices.
Accuracy and equivalence testing of crown ratio models and assessment of their impact on diameter growth and basal area increment predictions of two variants of the Forest Vegetation Simulator
Authors: Leites Laura P. , Robinson Andrew P. , Crookston Nicholas L.
Published: April 2009

Diameter growth (DG) equations in many existing forest growth and yield models use tree crown ratio (CR) as a predictor variable. Where CR is not measured, it is estimated from other measured variables. We evaluated CR estimation accuracy for the models in two Forest Vegetation Simulator variants: the exponential and the logistic CR models used in the North Idaho (NI) variant, and the Weibull model used in the South Central Oregon and Northeast California (SO) variant. We also assessed the effects of using measured (CRm) versus predicted (CRp) crown ratio for predicting 10 year DG and 30 year basal area increment (BAI). Evaluation criteria included equivalence tests, bias, root mean square error, and Spearman’s coefficient of rank correlation. Inventory data from the Winema and the Colville National Forests were used. Results showed that the NI variant models overpredicted CR when CRm was below 40% and underpredicted CR when it was above 60%, whereas the SO variant model overpredicted CR when CRm was smaller than 60%. Differences between CRm and CRp were positively correlated with differences in DG predictions. Using CRm versus CRp resulted in 30 year BAI absolute percent differences of 10% or less for more than 50% of the plots.