Challenges of Buffer Zone Management in Cross River National Park, South Eastern Nigeria

Ecological buffer zones are very crucial in minimizing the impact of land use practices close to protected areas, though there is no consensus surrounding their objectives, location, area and the level of their permitted use. This study therefore assessed the challenges of buffer zone management in some (adjacent) support zone communities in Oban Division of Cross River National Park, Nigeria. Data were obtained through questionnaire interviews and reconnaissance survey and subjected to descriptive and inferential statistical analysis. Results showed that a high percentage (68.68%) of the respondents in the division were not aware of the existence of the buffer zone and the policies governing it. 74.42% believed that the Park has left them poorer. Only 11.21% accepted that they have enjoyed tremendous benefits as a result of the establishment of Park and its buffer zone. A chi-square analysis showed that the people were not aware of the existence, creation and policy governing buffer zone management and were therefore not in favour of its operations. These developments might be adduced to the low level of awareness of Park laws and buffer zone management policies by these communities. It is therefore recommended that public enlightenment campaigns should be stepped up to educate the populace on the need to abide by the laws and policies governing the Park and its buffer zone. Social amenities including classroom blocks, health centers, roads, water and electricity should be provided by the management of the park including training in a number of livelihood options like beekeeping and non timber forest product farming. This is expected to reduce the pressure by the local communities on the resources of the park and its buffer zone

Towards automation of chemical process route selection based on data mining

A methodology for chemical routes development and evaluation on the basis of data-mining is presented.This work was in part funded by EPSRC project “Terpene-based manufacturing for sustainable chemical feedstocks” EP/K014889

Open Problems on Central Simple Algebras

We provide a survey of past research and a list of open problems regarding central simple algebras and the Brauer group over a field, intended both for experts and for beginners.Comment: v2 has some small revisions to the text. Some items are re-numbered, compared to v

Current measurement by real-time counting of single electrons

The fact that electrical current is carried by individual charges has been known for over 100 years, yet this discreteness has not been directly observed so far. Almost all current measurements involve measuring the voltage drop across a resistor, using Ohm's law, in which the discrete nature of charge does not come into play. However, by sending a direct current through a microelectronic circuit with a chain of islands connected by small tunnel junctions, the individual electrons can be observed one by one. The quantum mechanical tunnelling of single charges in this one-dimensional array is time correlated, and consequently the detected signal has the average frequency f=I/e, where I is the current and e is the electron charge. Here we report a direct observation of these time-correlated single-electron tunnelling oscillations, and show electron counting in the range 5 fA-1 pA. This represents a fundamentally new way to measure extremely small currents, without offset or drift. Moreover, our current measurement, which is based on electron counting, is self-calibrated, as the measured frequency is related to the current only by a natural constant.Comment: 9 pages, 4 figures; v2: minor revisions, 2 refs added, words added to title, typos correcte

A pilot study comparing the metabolic profiles of elite-level athletes from different sporting disciplines

Background: The outstanding performance of an elite athlete might be associated with changes in their blood metabolic profile. The aims of this study were to compare the blood metabolic profiles between moderate- and high-power and endurance elite athletes and to identify the potential metabolic pathways underlying these differences. Methods: Metabolic profiling of serum samples from 191 elite athletes from different sports disciplines (121 high- and 70 moderate-endurance athletes, including 44 high- and 144 moderate-power athletes), who participated in national or international sports events and tested negative for doping abuse at anti-doping laboratories, was performed using non-targeted metabolomics-based mass spectroscopy combined with ultrahigh-performance liquid chromatography. Multivariate analysis was conducted using orthogonal partial least squares discriminant analysis. Differences in metabolic levels between high- and moderate-power and endurance sports were assessed by univariate linear models. Results: Out of 743 analyzed metabolites, gamma-glutamyl amino acids were significantly reduced in both high-power and high-endurance athletes compared to moderate counterparts, indicating active glutathione cycle. High-endurance athletes exhibited significant increases in the levels of several sex hormone steroids involved in testosterone and progesterone synthesis, but decreases in diacylglycerols and ecosanoids. High-power athletes had increased levels of phospholipids and xanthine metabolites compared to moderate-power counterparts. Conclusions: This pilot data provides evidence that high-power and high-endurance athletes exhibit a distinct metabolic profile that reflects steroid biosynthesis, fatty acid metabolism, oxidative stress, and energy-related metabolites. Replication studies are warranted to confirm differences in the metabolic profiles associated with athletes’ elite performance in independent data sets, aiming ultimately for deeper understanding of the underlying biochemical processes that could be utilized as biomarkers with potential therapeutic implications

Formulación y evaluación de liberación sostenida oral de Diltiazem clorhidrato usando resina como material formador de matriz

Rosin, a natural resin, was used as a hydrophobic matrix material for the controlled release, using diltiazem HCl as model drug. Matrix tablets were prepared by direct compression method using rosin as matrix forming material in different proportions and with different diluent combinations. The tablets prepared were flat faced, retained their shape throughout. The method of preparation of matrix system and its concentration were found to have pronounced effect on the release of diltiazem HCl. The release was found to follow both the first order kinetics and fickian diffusion. The drug delivery was analyzed using the paddle method according to USP XXIII. All the studies were done in phosphate buffer pH 7.4. The matrix tablets were evaluated for its thickness, hardness, friability, weight variation, drug content and invitro release studies. The results suggest that the rosin is useful in developing sustained release matrix tablets, prolong release of water soluble drug for up to 24h. Rosin thus promises considerable utility in the development of oral sustained release drug delivery systems.Colofonia, una resina natural, se utilizó como un material de matriz hidrofóbica para la liberación controlada, utilizando HCl diltiazem como fármaco modelo. Los comprimidos de matriz se prepararon por el método de compresión directa usando resina como material formador de matriz en diferentes proporciones y con diferentes combinaciones de diluyente. Las tabletas preparadas eran de cara plana, conservan su forma en todas partes. El método de preparación del sistema de matriz y su concentración se encontró que tenían efecto pronunciado sobre la liberación de diltiazem HCl. La liberación se encontró que sólo deben observarse las cinética de primer orden y de difusión de Fick. La administración de fármacos se analizó mediante el método de paletas de acuerdo con la USP XXIII. Todos los estudios se realizaron en tampón de fosfato de pH 7,4. Se evaluaron los comprimidos de matriz de su espesor, dureza, friabilidad, variación de peso, contenido de drogas y de liberación in vitro estudios. Los resultados sugieren que la colofonia es útil en el desarrollo de tabletas de matriz de liberación sostenida, prolongar la liberación del fármaco soluble en agua durante un máximo de 24 horas. así colofonia promete considerable utilidad en el desarrollo de sistemas de administración de fármacos de liberación sostenida oral

Automation of route identification and optimisation based on data-mining and chemical intuition.

Data-mining of Reaxys and network analysis of the combined literature and in-house reactions set were used to generate multiple possible reaction routes to convert a bio-waste feedstock, limonene, into a pharmaceutical API, paracetamol. The network analysis of data provides a rich knowledge-base for generation of the initial reaction screening and development programme. Based on the literature and the in-house data, an overall flowsheet for the conversion of limonene to paracetamol was proposed. Each individual reaction-separation step in the sequence was simulated as a combination of the continuous flow and batch steps. The linear model generation methodology allowed us to identify the reaction steps requiring further chemical optimisation. The generated model can be used for global optimisation and generation of environmental and other performance indicators, such as cost indicators. However, the identified further challenge is to automate model generation to evolve optimal multi-step chemical routes and optimal process configurations.This work was funded in part by the EPSRC project “Terpenebased Manufacturing for Sustainable Chemical Feedstocks” EP/K014889. The PhD scholarship of WC is funded by the EPSRC Doctoral Training Centre in Sustainable Chemical Technologies (EP/G03768X/1). We gratefully acknowledge collaboration with RELX Intellectual Properties SA and their technical support, which enabled us to mine REAXYS. PMJ is grateful to Peterhouse and the Cambridge Trust for PhD scholarships