Study of Z Boson Pair Production in e+e- Collisions at LEP at \sqrt{s}=189 GeV

The pair production of Z bosons is studied using the data collected by the L3 detector at LEP in 1998 in e+e- collisions at a centre-of-mass energy of 189 GeV. All the visible final states are considered and the cross section of this process is measured to be 0.74 +0.15 -0.14 (stat.) +/- 0.04 (syst.) pb. Final states containing b quarks are enhanced by a dedicated selection and their production cross section is found to be 0.18 +0.09 -0.07 (stat.) +/- 0.02 (syst.) pb. Both results are in agreement with the Standard Model predictions. Limits on anomalous couplings between neutral gauge bosons are derived from these measurements

Tree Species Diversity in a Semi-Conserved Beach Forest in Southern Philippines

Beach forest is a unique type of ecosystem, a mixed group of littoral creepers, shrubs, and trees above the high tide level. In Sarangani Province, beach forest is not well studied even though it experienced various environmental threats due to the increase of coastal development and tourism. This study aimed to determine the composition and diversity of beach forest species in Barangay Kling, Kiamba, Sarangani Province and relate it to the whole coastal area of the municipality by producing a profile. Specifically, the study sought to determine the species composition of beach forest in the sampling areas; assess the beach forest diversity of at least three sampling areas in Barangay Kling. Using transect-quadrat method, species were identified through identification guides. Data analysis includes relative density, relative frequency, relative dominance, species diversity index and species importance value. Results of the assessment of species composition and community structure showed that a total of 39 beach forest species distributed among 23 families are present on the site, and another ten (10) species were observed outside of the transects. Milletia pinnata has the highest importance value with a rating of 79.04, followed by Terminalia catappa (65.54) and Barringtonia asiatica (44.04). The results show that the area has a huge potential for development into a beach forest park considering the diversity and maturity of the stand. In addition, management, protection, and rehabilitation of beach forest are also highly recommended to maximize their potential as climate change mitigators and their role in coastal protection