Tree Composition and Seedling Recruitment in Urban and Rural Forests

In 1993, Dr. Nancy Broshot randomly located 25 permanent study sites in Forest Park in Portland, Oregon to examine the effects of urbanization on forest health. Plant community structure was examined. In 2003, Dr. Broshot reexamined the plant communities at each site and found significantly higher tree mortality and reduced recruitment (young trees) in all areas of the park. Many seedlings that had been present in 1993 were absent in 2003. In 2013, a 20-year follow up study of the tree community was conducted. Although the rate of tree mortality had dropped, recruitment of seedlings and saplings was still low. A series of lichen studies completed at each site in 2013 indicated high levels of nitrogenous air pollution at all sites in the park. In 2014, three control sites along a gradient of air quality in the Mount Hood National Forest above Estacada, Oregon were added to the study. Plant community variables were measured in the same manner as in Forest Park. We found significantly more live trees, saplings and seedlings at the control sites than at sites in Forest Park. We also found significantly fewer dead trees at control sites. Indeed, we had more seedlings at the three control sites than at all 25 of the Forest Park sites. We believe the low level of recruitment may be due to nitrogenous deposition from air pollution in Forest Park; we are waiting for results from collected soil samples to evaluate this hypothesis

Distributed QoS Guarantees for Realtime Traffic in Ad Hoc Networks

In this paper, we propose a new cross-layer framework, named QPART ( QoS br>rotocol for Adhoc Realtime Traffic), which provides QoS guarantees to real-time multimedia applications for wireless ad hoc networks. By adapting the contention window sizes at the MAC layer, QPART schedules packets of flows according to their unique QoS requirements. QPART implements priority-based admission control and conflict resolution to ensure that the requirements of admitted realtime flows is smaller than the network capacity. The novelty of QPART is that it is robust to mobility and variances in channel capacity and imposes no control message overhead on the network

Optical Spectroscopic Determination of the Zero-Field Splitting in Vibronic Levels of the Triplet State of Nitrite

We have used conventional high resolution optical spectroscopic methods to determine the principal values of the fine structure tensor for the lowest triplet state (3B1 at 18 959 cm^−1) of NO2 - in Na NO2 single crystals. From the intensities in the Zeeman spectrum we find [dformula D - E = 0.86 [plus-minus] 0.04cm[sup -1],] [dformula D + E = 0.40 [plus-minus] 0.04cm[sup -1],] where the z axis is taken as the twofold axis and E = (Z − X) / 2. From the measurement of line positions in the high-field Zeeman spectrum we find D − E = 0.84 ± 0.05cm−1,D + E = 0.41 ± 0.05cm−1. The values of D and E calculated for one-center spin–spin interaction are D − E = 0.42cm^−1 and D + E = 0.24cm^−1. The calculated ordering of the spin states is the same as that observed, but we suggest that there is significant second-order spin–orbit energy associated with the real splittings. Roughly the same splittings are seen for different vibronic levels of 3B1 associated with nu2[prime

Studies of the 3455-Å Triplet State of s-Triazine

We present a confirmation of the assignment of the 28 935-cm^−1 triplet state, 3A1[double-prime], of s-triazine. The high-field Zeeman effect is used to make this assignment which is consistent with the fact the transition is polarized perpendicular to the molecular plane. The optical spectrum at low magnetic fields yields the zero-field splitting D=−0.058±0.024 cm^−1. The sign and magnitude of D is consistent with an npi* state in which one-center spin—spin interaction is a significant feature of the zero-field splitting

Initial subjective load carriage injury data collected by interviews and questionnaires

This study aimed to identify the types, incidence, and causes of any potential load carriage injuries or discomfort as a result of a 2-hour, forced-speed, treadmill march carrying 20 kg. Subjective load carriage data were collected, through both interviews and questionnaires, from relatively inexperienced soldiers after a period of load carriage. Results from the study showed that the upper limb is very susceptible to short-term discomfort, whereas the lower limb is not. The shoulders were rated significantly more uncomfortable then any other region, and blisters were experienced by ∼60% of participants. Shoulder discomfort commences almost as soon as the load is added and increases steadily with time; however, foot discomfort increases more rapidly once the discomfort materializes. In conclusion, early development of shoulder pain or blisters may be a risk factor for severe pain or noncompletion of a period of prolonged load carriage

Digging Deeper: James Connolly in America

This project continued research into James Connolly\u27s time in America from 1902-1910. It focused on primary sources in the hopes to unearth things not found in the secondary writing on Connolly’s activities during this influential time. The O’Brien papers are an eclectic collection of primary documents from Connolly’s life, including letters between James Connolly and his friend John Matheson, correspondence with other socialists, and some of Connolly’s own writing. The New York Call was a daily socialist newspaper that contains ads for Connolly’s lectures and his magazine, The Harp, as well as meetings of his organization, the Irish Socialist Federation. Through these primary sources and others, more of James Connolly’s activities and perspectives during his time in America come to light