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Mountain pine beetle, Dendroctonus ponderosae Hopkins, is the most significant mortality agent in pine forests of western North America. Silvicultural treatments that reduce the number of susceptible host trees, alter age and size class distributions, and diversify species composition are considered viable, long-term options for reducing stand susceptibility to mountain pine beetle-caused tree mortality. Short-term efficacy of thinning treatments has been evaluated, but long-term efficacy has not. We evaluated mountain pine beetle-caused lodgepole pine mortality in 2008, ∼28 years after diameterlimit cutting from above that removed the largest diameter lodgepole pines in a Wyoming, USA forest. Following extensive recent mountain pine beetle activity, the partially-cut stands had significantly less mountain pine beetle-caused tree mortality compared to untreated reference stands. These results are similar to observations five years post-treatment, albeit using different reference stands because the original controls were lost to timber harvest. The original management objective was reduced mountain pine beetle-caused tree mortality, and this objective was achieved, lasting for up to 28 years. Despite the reduced mortality among partially-cut stands, however, untreated and treated stands had similar densities of residual live mature lodgepole pine and those in untreated stands had larger average diameters.

Regular exercise training is recognized as a powerful tool to improve work capacity, endothelial function and the cardiovascular risk profile in obesity, but it is unknown which of high-intensity aerobic exercise, moderate-intensity aerobic exercise or strength training is the optimal mode of exercise. In the present study, a total of 40 subjects were randomized to high-intensity interval aerobic training, continuous moderate-intensity aerobic training or maximal strength training programmes for 12 weeks, three times/week. The high-intensity group performed aerobic interval walking/running at 85–95% of maximal heart rate, whereas the moderate-intensity group exercised continuously at 60–70% of maximal heart rate; protocols were isocaloric. The strength training group performed ‘high-intensity’ leg press, abdominal and back strength training. Maximal oxygen uptake and endothelial function improved in all groups; the greatest improvement was observed after high-intensity training, and an equal improvement was observed after moderate-intensity aerobic training and strength training. High-intensity aerobic training and strength training were associated with increased PGC-1α (peroxisome-proliferator-activated receptor γ co-activator 1α) levels and improved Ca2+ transport in the skeletal muscle, whereas only strength training improved antioxidant status. Both strength training and moderate-intensity aerobic training decreased oxidized LDL (low-density lipoprotein) levels. Only aerobic training decreased body weight and diastolic blood pressure. In conclusion, high-intensity aerobic interval training was better than moderate-intensity aerobic training in improving aerobic work capacity and endothelial function. An important contribution towards improved aerobic work capacity, endothelial function and cardiovascular health originates from strength training, which may serve as a substitute when whole-body aerobic exercise is contra-indicated or difficult to perform.

Diabetes mellitus (DM) increases the risk of heart failure after myocardial infarction (MI), and aggravates ventricular arrhythmias in heart failure patients. Although exercise training improves cardiac function in heart failure, it is still unclear how it benefits the diabetic heart after MI. To study the effects of aerobic interval training on cardiac function, susceptibility to inducible ventricular arrhythmias and cardiomyocyte calcium handling in DM mice after MI (DM-MI). Male type 2 DM mice (C57BLKS/J Lepr (db) /Lepr (db) ) underwent MI or sham surgery. One group of DM-MI mice was submitted to aerobic interval training running sessions during 6 weeks. Cardiac function and structure were assessed by echocardiography and magnetic resonance imaging, respectively. Ventricular arrhythmias were induced by high-frequency cardiac pacing in vivo. Protein expression was measured by Western blot. DM-MI mice displayed increased susceptibility for inducible ventricular arrhythmias and impaired diastolic function when compared to wild type-MI, which was associated with disruption of cardiomyocyte calcium handling and increased calcium leak from the sarcoplasmic reticulum. High-intensity exercise recovered cardiomyocyte function in vitro, reduced sarcoplasmic reticulum diastolic calcium leak and significantly reduced the incidence of inducible ventricular arrhythmias in vivo in DM-MI mice. Exercise training also normalized the expression profile of key proteins involved in cardiomyocyte calcium handling, suggesting a potential molecular mechanism for the benefits of exercise in DM-MI mice. High-intensity aerobic exercise training recovers cardiomyocyte function and reduces inducible ventricular arrhythmias in infarcted diabetic mice.

Diabetic patients have greater risk of developing congestive heart failure (HF) after myocardium infarction (MI). Exercise training is an effective strategy for preventing the development of cardiomyopathies and the incidence of cardiovascular morbidity and mortality during diabetes.Aim - To study the effects of aerobic interval training (AIT) on cardiac function and the role of calcium handling in a combined experimental model of MI-induced HF and diabetic cardiomyopathy.Methods and Results - A cohort of male diabetic db/db and age-matched nondiabetic control mice was randomly assigned into untrained and trained sham and MI groups. MI was induced by coronary ligation. Exercise tolerance was evaluated by VO2 max. Standard echocardiography and tissue Doppler imaging were performed by high-resolution in-vivo imaging system, and diastolic sarcoplasmic reticulum (SR) calcium leak was measured in isolated cardiomyocytes using fluorescence microscope. MI diabetic mice displayed higher mortality rate compared to MI nondiabetic and sham mice (55% vs. 25% and 0%, respectively). In addition, exercise intolerance, reduced fractional shortening (FS), and cardiomyocyte dysfunction were observed in MI diabetic mice compared to other groups. AIT increased survival rate and exercise tolerance in MI diabetic to diabetic sham levels, paralleled by increased FS. AIT reestablished contractile function of MI diabetic to diabetic sham levels associated with improved SR calcium release synchronicity, T-tubule density and SR calcium leak.Conclusion - These results provide evidence for improvement of calcium handling by AIT in MI-induced HF during diabetes. Therefore, AIT is a potential therapeutic tool for the management of HF associated with diabetes.

Alaska-cedar, Chamaecyparis nootkatensis (D. Don) Spach, has been dying in undisturbed forests throughout southeast Alaska for the last 100 years. To determine if decline spreads, boundaries of mortality at seven sites with decline were mapped using aerial photographs taken in 1927, 1948, 1965, and 1976. Mortality was present at all seven sites in 1927. The boundaries of mortality have since expanded, but not by more than 100 m beyond the 1927 limit. In ground surveys, dead Alaska-cedar trees, classified according to their degree of deterioration, were recorded in 427 plots along 39 transects. Fifty-five taxa of understory vegetation were also recorded from 280 plots along these 21 transects; an ordination was produced from their distribution that represented a gradient from bogs to sites with better drainage. Most mortality was associated with bog and semibog sites. Alaska-cedar has a disproportionate level of mortality (65% of basal area dead) relative to other conifers. Local spread of cedar decline occurred along this gradient, as plots with more recently killed cedar trees had high average ordination scores (better drainage) and plots with cedars killed long ago had low average scores (boggy). Snags that probably date from the onset of extensive mortality were relatively common (at least 8% of all snags) on all 23 sites where intensive mortality was surveyed on the ground. As all sites with mortality that we investigated throughout southeast Alaska have these snags, decline does not appear to have spread to new sites since its onset. Although decline is relatively species specific and has patterns of local spread, the spread of mortality is along a specific, preexisting ecological gradient. These results, and the apparent lack of any site to site spread in the last 100 years, suggest that Alaska-cedar decline is not caused by some biotic agent.

Phytophthora ramorum (Oomycetes) is an emerging plant pathogen in forests in southwestern Oregon (Curry County). Moreover, since 2003 it has been repeatedly isolated from plants in Oregon nurseries. In this study, we analysed the genetic diversity of the P. ramorum population in Oregon from 2001 to 2004 by using microsatellites. A total of 323 isolates (272 from the infested forest; 51 from nurseries) were screened at 10 loci. The overall P. ramorum population in Oregon is characterized by low genetic diversity and has all the hallmarks of an introduced organism. All isolates within the A2 mating type belonged to the same clonal lineage and no recombinant genotypes were found. The forest population (24 genotypes) was dominated by a single multilocus genotype which persisted over years, indicating that eradication efforts in the forest have not completely eliminated inoculum sources. In contrast, genotypic evidence suggests that eradication was effective in nurseries. In 2003 and 2004, a total of 11 genotypes were found in the nurseries (one belonged to the European lineage of P. ramorum) but no genotype was recovered in both sampling years. Significant differentiation and low gene flow were detected between nursery and forest populations. Only two nursery genotypes were also found in the forest, and then at low frequency. Thus, the nursery infestation is not caused by the genotypes observed in Curry County, but likely resulted through introduction of novel genotypes from nurseries out-of-state. This highlights the continued importance of sanitation and quarantine in nurseries to prevent further introduction and spread of P. ramorum.

Do insulin pumps deliver more insulin at lower environmental pressures and, if so, is this due to pump dysfunction or to formation of bubbles in the insulin solutions? H-TRON V-100 (Hoechst Infusor V-100), MRS-1 (Disetronic), Nordic Infusor MK II (Novo Nordisk) and Minimed 504-S (Minimed Technology) insulin pumps were studied at 0.9 ATA and 0.8 ATA with constant infusion 2.0 I.U./hour. H-TRON V-100 was also studied at 0.7 ATA at the same infusion rate and with the motor in stop position. The results indicated that all pumps delivered slightly more insulin than the set rate during decompression (max. single value 2.68 I.U. extra delivered at 0.7 ATA, max. average value 1.32 I.U. extra delivered at 0.8 ATA). An equivalent amount of insulin (1.72 I.U.) was delivered at 0.7 ATA without running the motor. This implies that the extra insulin supplied was caused by physically dissolved nitrogen and oxygen in the insulin solution, and was not due to dysfunction of the pumps.

In order to assess whether running training for many years predisposes to arthrosis in the lower limbs, the hips, knees and ankle joints of 30 runners who began running training at the beginning of the nineteen fifties were examined. Three of these runners were no longer active. One of these had given up late in the nineteen seventies on account of arthroses in the upper and lower limbs i.e. changes which can scarecely be attributed to the stresses of running. The remaining 27 (90%) had run 20-40 km/week throughout 40 years. Subjective, objective and radiological data were compared with data from 27 non-active control persons who were comparable as regards age, weight/height and occupational stress with the runners. We found no differences in joint mobility, axial deviations or complaints of pain between the two groups. Radiologically, the distances between the osseous joint surfaces in the hip and ankle joints and the degrees of degeneration in the knees were assessed according to Ahlback's classification without any differences being found between the groups. Our results suggest that running training to a moderate extent for many years does not predispose to arthrosis in the lower limbs in healthy individuals.

Stumps and roots of trees harvested 20, 30, and 50 years ago were examined for survival of Phellinusweirii. Survival was compared among sites regenerated to Pseudotsugamenziesii (Douglas-fir) and Alnusrubra (red alder). Distinctive patterns of decay and the persistence of setal hyphae and zone lines after death of the fungus enabled documentation of survival time and of the retreat of P. weirii from roots. Phellinusweirii often died from a decay column without colonizing adjacent sound wood.Data from 1076 roots on 340 stumps were analyzed. After 50 years, the fungus survived in 26% of the stumps and in 11% of the roots sampled. Surface mycelium was present on 17% of the roots after 20 years, 15% after 30 years, and 1% after 50 years. The decrease in survival time was similar on sites presently occupied by red alder or by Douglas-fir. Survival was not correlated with stump diameter or degree of deterioration after 20 and 30 years. In the current stand, trees killed by P. weirii were found within 5 m of 45% of infected stumps after 50 years.

Chemically induced dynamic electron polarization (CIDEP) from photolytically generated p‐benzosemiquinone radicals is studied by time resolved steady state experiments. The experimental time resolved intensity curves are fitted to curved derived from theory. Two different polarization contributions are observed with ethylene glycol as solvent. A hyperfine independent initial polarization P∞(I) =−0.107 is due to a triplet mechanism (TM) and a hyperfine dependent polarization (−0.032?P*⩽0.032) is caused by a radical pair mechanism (RPM) due to the radical termination reaction. P∞(I) =−0.034 when isopropanol is used as solvent. The solvent dependence of P∞(I) is consistent with the microscopic theory and the observed values of P∞(I) are indicative of a triplet lifetime in the range 0.1–10 nsec and a zero field parameter ‖D‖≳700 G. The magnitude and hyperfine dependence of P* is in accord with the microscopic theory for an exponentially decaying exchange interaction J (r) with the maximum value J0≳109 rad/sec...

Root-feeding insects are known to vector black-stain root disease in Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco). Intertree spread through root grafts and limited growth through soil is demonstrated as well. In potted seedling experiments, contact between roots of inoculated and healthy seedlings was either allowed or prevented. Transmission occurred in both treatments but was significantly more frequent (P = 0.01) when intertree root contact was allowed. In the root-contact treatment, 67% of the receptor seedlings died as a result of successful transmission. In the noncontact treatment, 35% of the receptor seedlings died. Evidence points to wounds on fine roots as principal infection courts. Root graft transmission of C. wageneri was verified through field excavation and microscopic examination of 23 root grafts from three widely separated sites.

A brief prospective of hydrologic analysis used for determination of spillway sizing is presented. The paper describes the procedures for determining a reasonable upper limit of flood potential for a given drainage basin. In 1936, the National Weather Service and the Corps of Engineers reached a cooperative agreement whereby meteorologists of the Weather Service would use their professional capabilities to develop probable maximum precipitation estimates. In recent years the Bureau of Reclamation and the Soil Conservation Service have joined forces with the Weather Service and the Corps of Engineers in the preparation of hydrometeorological reports. The four agencies are presently engaged in a major study of probable maximum precipitation for the northwestern United States. Information on major storms and floods is included that supports the hydrometeorological approach. The paper points out that the major federal dam construction agencies have been meeting regularly and are using the same basic hydrometeorological approach to size spillways.

Dougls-fir (Pseudotsugamenziesii (Mirb.) Franco) trees 12–32 years old were inoculated with four isolates of the fungus Phellinusweirii (Murr.) Gilb in 20 plantations in western Oregon. Mycelium grew onto roots from inoculum blocks in 54% of 759 inoculations, but the fungus appeared to be alive on only 32% of the roots after 2 years. The average maximum extent of ectotrophic growth on successfully inoculated roots was 13.2 cm. Inoculation success and mycelial growth were greater for the two isolates originating from an area of severe root rot than for the two isolates from an area with light damage. Mycelial growth on roots differed among plantations, but there was no correlation between naturally occurring root rot damage and inoculation success or mycelial growth.

The effects were studied of varying amounts and forms of N fertilizers on the chemical composition of soil solution and on the uptake of N, K, Na, Ca and Mg by barley.

Extensive electron paramagnetic resonance (EPR) studies of potassium in ethylamine—ammonia mixtures were made over a temperature range of −180° to +100°C and at varying ammonia concentrations up to 68 mole %. Hyperfine splittings, g values, linewidths, and spin concentrations were measured. Optical spectra were measured from −65° to +35°C for a number of the solutions.Correlation of optical and EPR results rules out the assignment of the visible absorption to the monomeric species responsible for hyperfine splitting. The unusual temperature dependence of the EPR spectra cannot be explained in the light of current models, nor can the ammonia dependence be quantitatively interpreted. A model involving equilibrium between atoms and monomers quantitatively describes the temperature dependence. To explain the dependence upon ammonia concentration, it is necessary to consider two monomeric species, one fully solvated by ethylamine and the other involving replacement of ethylamine by one molecule of ammonia.Abov...

Cold hands is a common complaint in myxoedema and were reported by 15 of 17 patients before treatment of myxoedema with 4 having Raynaud's phenomenon. An increased cold sensitivity of the digital arteries could be demonstrated during finger cooling in about half of the patients and Raynaud's phenomenon was verified in the 4 patients as digital arterial closure. The cold sensitivity decreased significantly after treatment with L-thyroxine. The increased cold sensitivity in untreated myxoedema is probably due to an increased sympathetic discharge to the hands that might disclose a predisposition for Raynaud's phenomenon.

The widespread use of beta blockers in treatment of both cardiovascular and nonvascular conditions has generated interest in changes in functions of the central nervous system during treatment. We studied the effect of 3 weeks of beta blockade on learning and memory ability, concentration, and verbal abstraction in 32 young normotensive healthy men. We chose healthy males to exclude the possible influence of changes related to a hypertensive state. Subjects were randomized into a 3-week treatment protocol with either atenolol 50 mg X 2 (cardioselective, hydrophilic), metoprolol 100 mg X 2 (cardioselective, lipophilic), propranolol 80 mg X 2 (noncardioselective, lipophilic), or placebo X 2. Each subject underwent two neuropsychological testing sessions. We found no significant enhancement or impairment of intellectual or psychomotor performances after the 3-week treatment with beta-adrenergic-blocking agents compared to a placebo-treated control group. Differences in pharmacokinetic profiles of the drugs (e.g., central nervous system penetrability, lipophilicity, or membrane-stabilizing effect) did not influence the test outcome. Antihypertensive treatment with beta blockers over a prolonged period does not affect young peoples' learning and memory abilities or reasoning powers, nor their ability to concentrate and perform psychometric tasks.

Diabetic cardiomyopathy is characterized by early-onset diastolic dysfunction and late-onset systolic dysfunction. However, little is known about the mechanisms underlying the response of the diabetic myocardium to ischemia.Aim - To study the left ventricular (LV) dysfunction and the role of calcium handling in infarcted diabetic mice in an early stage of diabetic cardiomyopathy.Methods and Results - A cohort of male diabetic db/db and age-matched nondiabetic control mice at 10 wk of age was randomly assigned into Sham and myocardial infarction (MI) groups. MI was induced by coronary ligation. Standard echocardiography and tissue Doppler imaging were performed by high-resolution in-vivo imaging system, and diastolic sarcoplasmic reticulum (SR) calcium leak was measured in isolated cardiomyocytes using fluorescence microscope. One month after MI, 75% of the nondiabetic mice survived vs. 55% of the MI diabetic mice (p=0.04). A significant LV dilatation was observed in MI diabetic mice compared to nondiabetic (p=0.03). Peak systolic tissue velocity (Sm) was 28% lower in MI diabetic mice than in nondiabetic group (nondiabetic: 19±1 vs. 17±2mm/s; diabetic: 18±2 vs. 13±2∗mm/s, ∗p=0.05, for Sham and MI, respectively). Peak early diastolic tissue velocity (Em) was decreased in both Sham and MI diabetic mice (17±2∗ and 16±4∗ vs. 25±3 and 25±4 mm/s, ∗p