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The Lauge-Hansen ankle fracture classification system is widely accepted and is utilized to describe and predict ankle fracture patterns based on the mechanism of injury. Multiple studies have shown inconsistencies in the Lauge-Hansen's ability to predict fracture patterns based on the mechanism of injury. We set out to determine if the posterior malleolar fracture pattern is associated with the fracture types described by Lauge-Hansen. In this retrospective cohort study, we reviewed 153 patients with trimalleolar ankle fractures as diagnosed using computed tomography scans. Timing of injury was from February 2013 to August 2017. Patient ages ranged between 18 and 89 years old. Each patient had a complete clinical and radiographic workup including a preoperative computed tomographic scan following initial fracture reduction in the emergency room. We classified each ankle fracture based on plain film radiographs using the Lauge-Hansen classification scheme. Each individual posterior malleolar fracture was evaluated on computed tomography imaging and described using both the Haraguchi and Bartonicek-Rammelt classification systems. Of the 153 patients identified with trimalleolar ankle fractures, 70% were female (±20%), the mean age was 51 y (±8 y), and the mean body mass index was 30 kg/m

Various techniques for estimating t∗ (travel time/quality factor Q) from short-period seismic-array records of body waves have been investigated. Spectral analysis in the frequency domain seems to be more appropriate for this purpose than time domain methods, because of the relative ease with which source and instrument effects can be removed. Of the techniques available, those based on maximum likelihood and homomorphic deconvolution give estimates of relative power versus frequency which best represent the power contained in a time-domain wavelet of short duration. The latter technique seemed to have better noise-eliminating properties than the former. Therefore, homomorphic deconvolution was used to obtain estimates of t∗ values from P, PcP, ScP and S phases recorded at the Warramunga array in the Northern Territory of Australia. The source regions for the event studied were the Sunda, Mariana, New Hebrides, Kermadec and Tonga trench zones. The short-period t∗ estimates obtained using the above method were much smaller than estimates from published free-oscillation Q models, indicating that the values of Q for compressional and shear waves are frequently-dependent. It was found that short-period t∗ values and free-oscillation Q models could be made consistent with one another by assuming Q = Q0(1+τω) where Q0 and τ are constants. The results of this investigation suggest another approach to how the Q structure of the mantle can be investigated.

In 1936, part of a dense 12-year-old aspen sucker stand was thinned. In the following year thinned and unthinned portions of the stand were underplanted with 2-2 white pine stock.By 1950, most seedlings were still small and slow-growing. Mortality among these individuals was high in the following 10 years but mortality was fairly light among seedlings of taller height classes. Height growth of seedlings continued to be poor so long as the crowns were below the shrub layer.White pine planted beneath young aspen stands require care at least until they are about 4 feet tall, especially on moist sites. The underbrush must be controlled, otherwise excessively high mortality and poor growth of the survivors will result.

This paper presents mathematical equations describing the relationships between the amount of stemflow per canopy layer per storm and the amount of gross rain per storm for four different canopy layers in a multi-storied forest community. The curves representing the relationships were curvilinear; for three of the canopy layers stemflow per storm increased at an increasing rate as gross rain per storm increased, approaching a constant rate of increase. Numerical values of the equation coefficients varied with canopy level in the forest stand profile and with variations in vegetal structure within the forest community. The lowest canopy in the vegetal profile, a fern canopy, had the most marked effect on rainfall redistribution.

Young red pine (Pinus resinosa Ait.) trees were grown under three watering treatments from late summer until early fall and under two watering treatments again the next spring. Size of apical buds, date of bud swell and bud burst in the spring, number of needle fascicles on the new shoots, shoot length, and needle-fascicle spacing were related to the first treatments. Most of these plant responses were correlated with bud size, and the correlations were unaffected by the spring watering treatments. The effect of treatments was on magnitude only, i.e. on mean sizes or mean numbers of the plant organs.In all cases in this experiment watering treatments during elongation had no effect on the results. Therefore in a species such as red pine, with determinate height growth, environment during bud formation played an important role in determining later shoot responses by acting on the bud size.Possibly the relationships reported here are genetically characteristic, unalterable by environment or at least by water alone. In this case the effect of environment on the trees was a proportionate increase or decrease in the size or number of plant organs.

This paper presents results of measurements, made separately for each of four canopy layers, of throughfall and stemflow in a multilayered stand of largetooth aspen (Populus grandidentata Michx.). Each canopy layer is identified by the predominant woody or fern species. Equations describe relationships between stemflow, stem size, and storm size, and between throughfall and storm size. In general, stemflow per stem per storm increased as both stem size and storm size increased, the latter having the greater effect. The equations varied with species. General stemflow equations were constructed to calculate stemflow per stem per storm for tree sizes and storm sizes within the measured range. Throughfall per storm increased as storm size increased, but at different rates for different canopy layers. Monthly budgets of interception, stemflow, and net rainfall for the various canopies, separately and together, were computed for the summer months of 1969 using the stemflow and throughfall equations, measured gross rainfall during all summer storms, and data on canopy structure for four plots within the stand. Interception by all canopies together amounted to 22 to 46% of monthly gross rainfall. Interception from the bracken fern canopy alone was 3 to 9%. Stemflow was about 8 to 17% of the monthly gross rainfall. The highest proportion of total stemflow was from bracken fern. Net rainfall was 54 to 78% of the monthly gross rainfall.

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