Estimation of bole biomass and carbon stocks through three volume equations for tree species in Ogba zoo, Nigeria

Precise and accurate estimates of bole Carbon Stocks (CS) sequestration are crucial for sustainable forest management related to climate change. Therefore, the study is aimed at estimating CS through three volume equations techniques with a view to identify how CS sequestration varies across volume equation. A total of ten (10) Temporary Sample Plots (TSPs) of 20m x 20m (0.04ha) in size were randomly laid in the study site. Tree species in all of the TSPs with a diameter ≥ 10 were measured for diameters and heights. Data were analysed using descriptive statistics, volume equations, regression and analysis of variance at α0.05. A total of twenty five (25) tree species comprising of fourteen (14) families were found in the TSPs from hundred and one (101) individual trees. There were differences in CS with respect to the three volume equations. There were very strong linear relationship between CS and the three volume equations with R2 value > 90%. There was statistical difference amongst Hossfeld’s equation, Geometric equation for the truncated cone and Smalian’s equation with t-Test value of 0.01, while Geometric equation for the truncated cone showed statistical difference with Hossfeld’s equation with t-Test value of 0.00. There was no statistical difference between Smalian’s equation and Geometric equation for the truncated cone with t-Test value of 0.57. Therefore, the scatter plots shows that the three bole volume equations are good predictors for estimating CS. However, Geometric equation for the truncated cone and Smalian’s equation had a high standard error and uncertainty values of 5%, 143% and 6%, 145%. Keywords: carbon stocks, carbon dioxide equivalent, volume equation, tree species, Ogba Zo

Educating Oncology Nurse Practitioners to Provide Basic Palliative Care

Background: Approximately 1.66 million Americans are diagnosed with cancer each year and another 589,430 die from the disease. As treatment options have expanded, many cancer patients are living longer with worsening symptoms and disabilities and an increased illness burden. These patients are ideal candidates for palliative care. Palliative care involves care delivered by a team of clinicians with specialty training and a focus on improving the quality of life for patients with serious illnesses. A number of major organizations have made formal recommendations regarding the integration of palliative care into comprehensive cancer care including the American Society of Clinical Oncology and the National Comprehensive Cancer Network. With an advanced education and scope of practice, a holistic orientation, and an evidence-base that substantiates their provision of safe and effective care, nurse practitioners (NPs) are well positioned to improve access to palliative care; yet, many NPs lack basic knowledge of palliative care and do not have competencies to provide such care. Objectives: This project aimed to measure differences in NPs’ knowledge of basic palliative care concepts and their self-rated self-competence in the provision of its care before and after a formal education program. Methods: This study used a one-group pre-post test design and valid and reliable instruments to measure the effects of an education intervention on NPs’ knowledge of basic palliative care and self-reported self-competence. The content for the education intervention, which was drawn from the End of Life Nursing Education Consortium’s (ELNEC) Advanced Practice Registered Nurse (APRN) curriculum, was delivered in one 8-hour program. The sample included NPs who practiced in the regional network sites of a National Cancer Institute designated comprehensive cancer center. Statistical differences were tested using paired t-tests, and a Wilcoxon Signed Ranks test. Results: A total of 37 NPs participated in the program. Knowledge, as measured by the ELNEC KAT increased from a mean of 89.03 to a mean of 90.49. Paired samples t tests revealed a statistically significant difference between the mean pre and mean post-test scores (t =-2.165, df =36, p= .037). Self-reported self-competence as measured by the PCNSC increased from a mean of 3.21 to a mean of 4.10. Paired samples t tests revealed that the difference between the mean pre and mean post PCNSC score was statistically significant (t =-9.202, df =36, p= .001). Conclusion: A one-day course based upon the ELNEC APRN clinical modules was effective in improving both knowledge, and self-competence of basic palliative care among oncology NPs

Bending Stiffness in Cadaveric and Composite Long Bones Following Total Joint Replacement

Several biomechanics studies have utilized commercially available replicate bone models as an alternative to cadaveric tissue specimens, in part due to their ease of handling and reduced expense. In an effort to validate the use of replicate bone specimens in biomechanics research, a number of studies have compared material properties of whole tibia and femur specimens to those of similar cadaveric specimens. Many of these validation studies have ascertained that the material properties of whole bone composite models fall within the range of those properties of cadaveric specimens, while offering reduced interspecimen variability. Current literature lacks, however, the direct comparison between cadaveric and composite specimens after the implantation of joint replacement components. Because of this, the interactions between orthopaedic implant and replicate bone model, and how those interactions compare with those between implants and cadaveric tissue, are relatively unknown. The purpose of this study was to evaluate the use of composite femur specimens in test scenarios aside from the whole-bone instances currently evaluated in the literature. Six cadaveric and six composite tibias and femurs were tested at different stages of surgical intervention. Flexural rigidity was measured using a 4-point bending test as a whole bone, after unicompartimental cut and implantation (UKA), and after total knee cut and implantation (TKA) or total hip arthroplasty (THA). The data did not show a definite trend between tests and specimens but is conclusive enough to use composite models for cadaveric specimens

Chronic toxicity of an environmentally relevant and equitoxic ratio of five metals to two Antarctic marine microalgae shows complex mixture interactivity

© 2018 Metal contaminants are rarely present in the environment individually, yet environmental quality guidelines are derived from single-metal toxicity data. Few metal mixture studies have investigated more than binary mixtures and many are at unrealistically high effect concentrations to freshwater organisms. This study investigates the toxicity of five metals (Cd, Cu, Ni, Pb, and Zn) to the Antarctic marine microalgae Phaeocystis antarctica and Cryothecomonas armigera. Two mixtures were tested: (i) an equitoxic mixture of contaminants present at their single-metal EC10 concentrations, and (ii) an environmental mixture based on the ratio metal concentrations in a contaminated Antarctic marine bay. Observed toxicity, as chronic population growth rate inhibition, was compared to Independent Action (IA) and Concentration Addition (CA) predictions parameterised to use EC10 values. This allowed for the inclusion of metals with low toxicities. The biomarkers chlorophyll a fluorescence, cell size and complexity, and intracellular lipid concentrations were assessed to investigate possible mechanisms behind metal-mixture interactions. Both microalgae had similar responses to the equitoxic mixture: non-interactive by IA and antagonistic by CA. Toxicity from the environmental mixture was antagonistic by IA to P. antarctica; however, to C. armigera it was concentration-dependent with antagonism at low toxicities and synergism at high toxicities by both IA and CA. Differences in dissolved organic carbon production and detoxification mechanisms may be responsible for these responses and warrants further investigation. This study shows that mixture toxicity interactions can be ratio, species, and concentration dependent. The responses of the microalgae to different mixture ratios highlight the need to assess toxicity at environmentally realistic metal ratios. Parameterising IA and CA reference models to use EC10s allowed for the inclusion of metals at low effect concentrations, which may otherwise be ignored. Reference mixture models are generally suitable for predicting chronic toxicity of metals to these marine microalgae at environmentally realistic ratios and concentrations. Toxic metal-mixture interactions were found to be concentration, ratio, and species dependent in exposures to two Antarctic marine microalgae

Pole Dancing: 3D Morphs for Tree Drawings

We study the question whether a crossing-free 3D morph between two straight-line drawings of an $n$-vertex tree can be constructed consisting of a small number of linear morphing steps. We look both at the case in which the two given drawings are two-dimensional and at the one in which they are three-dimensional. In the former setting we prove that a crossing-free 3D morph always exists with $O(\log n)$ steps, while for the latter $\Theta(n)$ steps are always sufficient and sometimes necessary.Comment: Appears in the Proceedings of the 26th International Symposium on Graph Drawing and Network Visualization (GD 2018

Assessing the Risk of Metals and Their Mixtures in the Antarctic Nearshore Marine Environment with Diffusive Gradients in Thin-Films

© 2019 American Chemical Society. Robust environmental assessments and contaminant monitoring in Antarctic near-shore marine environments need new techniques to overcome challenges presented by a highly dynamic environment. This study outlines an approach for contaminant monitoring and risk assessment in Antarctic marine conditions using diffusive gradients in thin-films (DGT) coupled to regionally specific ecotoxicology data and environmental quality standards. This is demonstrated in a field study where DGT samplers were deployed in the near-shore marine environment of East Antarctica around the operational Casey station and the abandoned Wilkes station to measure the time-averaged biologically available fraction of metal contaminants. The incorporation of DGT-labile concentrations to reference toxicity mixture models for three Antarctic organisms predicted low toxic effects (<5% effect to the growth or development of each organism). The comparison of metal concentrations to the Australian and New Zealand default water quality guideline values (WQGVs) showed no marine site exceeding the WQGVs for 95% species protection. However, all sites exceeded the 99% WQGVs due to copper concentrations that are likely of geogenic origin (i.e., not from anthropogenic sources). This study provides evidence supporting the use of the DGT technique to monitor contaminants and assess their environmental risk in the near-shore marine environment of Antarctica

Making GDPR Usable: A Model to Support Usability Evaluations of Privacy

We introduce a new model for evaluating privacy that builds on the criteria proposed by the EuroPriSe certification scheme by adding usability criteria. Our model is visually represented through a cube, called Usable Privacy Cube (or UP Cube), where each of its three axes of variability captures, respectively: rights of the data subjects, privacy principles, and usable privacy criteria. We slightly reorganize the criteria of EuroPriSe to fit with the UP Cube model, i.e., we show how EuroPriSe can be viewed as a combination of only rights and principles, forming the two axes at the basis of our UP Cube. In this way we also want to bring out two perspectives on privacy: that of the data subjects and, respectively, that of the controllers/processors. We define usable privacy criteria based on usability goals that we have extracted from the whole text of the General Data Protection Regulation. The criteria are designed to produce measurements of the level of usability with which the goals are reached. Precisely, we measure effectiveness, efficiency, and satisfaction, considering both the objective and the perceived usability outcomes, producing measures of accuracy and completeness, of resource utilization (e.g., time, effort, financial), and measures resulting from satisfaction scales. In the long run, the UP Cube is meant to be the model behind a new certification methodology capable of evaluating the usability of privacy, to the benefit of common users. For industries, considering also the usability of privacy would allow for greater business differentiation, beyond GDPR compliance.Comment: 41 pages, 2 figures, 1 table, and appendixe

High frequency continuous birefringence-induced oscillations in spin-polarized vertical-cavity surface-emitting lasers

Sustained, large amplitude and tunable birefringence-induced oscillations are obtained in a spin-vertical cavity surface-emitting laser (spin-VCSEL). Experimental evidence is provided using a spin-VCSEL operating at 1300 nm, under continuous-wave optical pumping and at room temperature. Numerical and stability analyses are performed to interpret the experiments and to identify the combined effects of pump ellipticity, spin relaxation rate, and cavity birefringence. Importantly, the frequency of the induced oscillations is determined by the device’s birefringence rate, which can be tuned to very large values. This opens the path for ultrafast spin-lasers operating at record frequencies exceeding those possible in traditional semiconductor lasers and with ample expected impact in disparate disciplines (e.g., datacomms, spectroscopy)