Effects of Ozone, Acid Mist and Soil Characteristics on Clonal Norway Spruce (Picea abies (L.) Kast.) - An Introduction to the Joint 14 Month Tree Exposure Experiment in Closed Chambers.

This paper introduces a series of publications referring to a single 14-month laboratory study testing the hypothesis that the recent decline of Norway spruce (Picea abies (L.) Karst.) at higher elevations of the Bavarian Forest and comparable forests in medium-range mountains and in the calcareous Alps is caused by an interaction of elevated ozone concentrations, acid mist and site-specific soil (nutritional) characteristics. The effect of climatic extremes, a further important factor, was not included as an experimental variable but was considered by testing of the frost resistance of the experimental plants. Results of these individual studies are presented and discussed in the following 14 papers. Plants from six pre-selected clones of 3-year-old Norway spruce (Picea abies (L.) Karst.) were planted in April 1985 in an acidic soil from the Bavarian Forest, or a calcareous soil from the Bavarian Alps. After a transition period, plants were transferred, in July 1986, into four large environmental chambers and exposed for 14 months to an artificial climate and air pollutant regime based on long-term monitoring in the Inner Bavarian Forest. The climatic exposure protocol followed realistic seasonal and diurnal cycles (summer maximum temperature, 26°C; total mean temperature, 9·8°C; winter minimum, −14°C; mean relative humidity, 70%; maximum irradiance, 500 W m−2; daylength summer maximum, 17 h; winter minimum, 8 h). Plants were fumigated with ozone, generated from pure oxygen (control: annual mean of 50 μg m−3; pollution treatment: annual mean of 100 μg m−3 with 68 episodes of 130–360 μg m−3 lasting 4–24 h), and background concentrations of SO2 (22 μg m−3) and NO2 (20 μg m−3); windspeed was set at a constant 0·6 m s−1. Plants were additionally exposed to prolonged episodes of misting at pH 5·6 (control) and pH 3·0 (treatment). Simulation of the target climatic and fumigation conditions was highly reliable and reproducible (temperature ± 0·5°C; rh±10%; ozone ±10 μg m−3; SO2 and NO2 ± 15 μg m−3). &nbsp

The effect of continuous ultrasound on chronic non-specific low back pain: a single blind placebo-controlled randomized trial

<p>Abstract</p> <p>Background</p> <p>Non-specific chronic low back pain (NSCLBP) is one of the most common musculoskeletal disorders around the world including Iran. One of the most widely used modalities in the field of physiotherapy is therapeutic ultrasound (US). Despite its common use, there is still inconclusive evidence to support its effectiveness in patients with NSCLBP. The objective of this study was to evaluate the effect of continuous US compared with placebo US additional to exercise therapy for patients with NSCLBP.</p> <p>Methods</p> <p>In this single blind placebo controlled study, 50 patients with NSCLBP were randomized into two treatment groups: 1) continuous US (1 MHz &1.5 W/cm²⁾ plus exercise 2) placebo US plus exercise. Patients received treatments for 4 weeks, 10 treatment sessions, 3 times per week, every other day. Treatment effects were assessed in terms of primary outcome measures: 1) functional disability, measured by Functional Rating Index, and 2) global pain, measured by a visual analog scale. Secondary outcome measures were lumbar flexion and extension range of motion (ROM), endurance time and rate of decline in median frequency of electromyography spectrum during a Biering Sorensen test. All outcome variables were measured before, after treatment, and after one-month follow-up. An intention to treat analysis was performed. Main effects of Time and Group as well as their interaction effect on outcome measures were investigated using repeated measure ANOVA.</p> <p>Results</p> <p>Analysis showed that both groups had improved regarding function (FRI) and global pain (VAS) (P < .001). Lumbar ROM as well as holding time during the Sorensen test and median frequency slope of all measured paravertebral muscles did not change significantly in either group (P > .05). Improvement in function and lumbar ROM as well as endurance time were significantly greater in the group receiving continuous US (P < .05).</p> <p>Conclusions</p> <p>The study showed that adding continuous US to a semi supervised exercise program significantly improved function, lumbar ROM and endurance time. Further studies including a third group of only exercise and no US can establish the possible effects of placebo US.</p> <p>Trial registration</p> <p>NTR2251</p