Finite connectivity systems as error-correcting codes

We investigate the performance of parity check codes using the mapping onto spin glasses proposed by Sourlas. We study codes where each parity check comprises products of K bits selected from the original digital message with exactly C parity checks per message bit. We show, using the replica method, that these codes saturate Shannon's coding bound for K?8 when the code rate K/C is finite. We then examine the finite temperature case to asses the use of simulated annealing methods for decoding, study the performance of the finite K case and extend the analysis to accommodate different types of noisy channels. The analogy between statistical physics methods and decoding by belief propagation is also discussed.

The metabolism of n-methyl compounds

The metabolism of compounds containing the N-methyl group is discussed with particular consideration being made to the possible role of the product of oxidative metabolism, the N-hydroxymethyl moiety, in the generation of potentially toxic, reactive electrophiles. Particular pathways which are considered are: (i), the production of formaldehyde; (ii), the generation of iminium ions or imines; and (iii), the formation of N-formyl compounds which might act as formylating agents. 4-Chloro-N-(hydroxymethyl)benzamide and 3-(4-chlorophenyl)-1-hydroxy-methyl-1-methylurea (the product of oxidative metabolism of 3-(4-chlorophenyl)-1,1-dimethylurea) are model carbinolamides which do not readily release formaldehyde. The electrophilic properties of these model carbinolamides were investigated: neither reacted with nucleophiles such as cyanide or glutathione under physiological conditions. In contrast, N-(acetoxymethyl)-4-chlorobenzamide yielded the cyanomethylamide with potassium cyanide and S-(4-chlorobenzamidomethyl)glutathione with glutathione. 4-Chloro-N-(hydroxymethyl)benzamide and 3-(4-chlorophenyl)-1,1-dimethylurea were not biotransformed to electrophilic moieties when incubated with mouse hepatic 9000 x g supernatant and Acetyl-CoA or PAPS-generating system. N-(Acetoxymethyl)-4-chlorobenzamide was non-mutagenic to Salmonella typhimurium in the short term bacterial assay; but toxicity to the bacteria was observed. 4-Chloro-N-(hydroxymethyl)benzamide and 3-(4-chlorophenyl)-1,1-dimethylurea showed no mutagenicity or toxicity in the mutagenicity assay including an Aroclor-induced rat hepatic 9000 x g supernatant. Addition of Acetyl-CoA or a PAPS-generating system did not produce a mutagenic response. 4-Chloro-N-formlbenzamide did not act as a formylating agent towards the weak nucleophile aniline. However, 4-chloro-N-formylbenzamide, N-formylbenzamide, 3-(4-chlorophenyl)-1-formyl-1-methylurea and 3-(4-chlorophenyl)-1-formylurea are all metabolised by mouse hepatic mirosomes and post-microsomal supernatant. The results demonstrate the potential for N-hydroxymethyl compounds to generate highly reactive species if these are substrates for conjugation with sulphate (or acetate). The model compounds employed here, apparently do not show any ability to be conjugated themselves, however, other N-hydroxymethyl compounds might be readily conjugated. The formation of N-formyl compounds does not appear to be toxicologically significant, as adjudged on limited experiments performed, but rather represent a detoxification pathway.

Conversion of a chirped Gaussian pulse to a soliton or a bound multisoliton state in quasi-lossless and lossy optical fiber spans

The formation of single-soliton or bound-multisoliton states from a single linearly chirped Gaussian pulse in quasi-lossless and lossy fiber spans is examined. The conversion of an input-chirped pulse into soliton states is carried out by virtue of the so-called direct Zakharov-Shabat spectral problem, the solution of which allows one to single out the radiative (dispersive) and soliton constituents of the beam and determine the parameters of the emerging bound state(s). We describe here how the emerging pulse characteristics (the number of bound solitons, the relative soliton power) depend on the input pulse chirp and amplitude. © 2007 Optical Society of America.

Fractional Powers of Almost Non-Negative Operators

Mathematics Subject Classification: Primary 47A60, 47D06.

The solution-seeking behavior of small Hungarian enterprises between 2006 and 2010

This paper describes the results of an investigation into the finance-related innovative ability of Hungarian micro, small and medium sized enterprises (SMEs) by using two datasets (from 2006 and 2010). The author explored SMEs’ levels of openness to new financial solutions and identified features which influence their innovative solution-seeking behavior. Additionally, changes in innovation between 2006 and 2010 were analyzed according to the SME sector and whether there is a correlation between having an active solution seeking attitude and business performance was examined. The findings show that shared/multiple ownership in businesses (having interests in different enterprises simultaneously) has a significant positive effect on flexibility and innovative ability. However, the size of the business, industrial sector, type of ownership and market of the SME also have some effect. Furthermore, the hypothesis that an active solution-seeking attitude increases after-tax performance per employee was confirmed.

Making chamber measurements of net ecosystem exchange in a short-hydroperiod Everglades marsh (at TS/Ph-1b), Taylor Slough

This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. This image is made available for non-commercial or educational use only.

The Mistranslation of the ABCs: An American AIDS Education Campaign in Botswana

The majority of Botswana citizens have access to national HIV/AIDS education, but the messages ignore native cultural practices. The purpose of this paper is to critique the influence of American humanism and individualism on the ABC model of HIV/AIDS prevention used to stem the AIDS epidemic in Botswana.

Tourism: Who Needs It?

Is tourism economically beneficial? If so, who benefits? How much of the money generated through tourism can be channeled into other projects so desperately needed by the community without harming the local tour market? Will tourism continue to grow forever, or is there an end in sight? The authors discuss how tourism will change in approaching the next century: and how people will change if tourism is to remain such an important economic facto

Charles E. Perry Having Fun

Charles Edward Perry (Chuck), 1937-1999, was the founding president of Florida International University in Miami, Florida. He grew up in Logan County, West Virginia and received his bachelor's and masters's degrees from Bowling Green State University. He married Betty Laird in 1960. In 1969, at the age of 32, Perry was the youngest president of any university in the nation. The name of the university reflects Perry’s desire for a title that would not limit the scope of the institution and would support his vision of having close ties to Latin America. Perry and a founding corps opened FIU to 5,667 students in 1972 with only one large building housing six different schools. Perry left the office of President of FIU in 1976 when the student body had grown to 10,000 students and the university had six buildings, offered 134 different degrees and was fully accredited. Charles Perry died on August 30, 1999 at his home in Rockwall, Texas. He is buried on the FIU campus in front of the Graham Center entrance.

The Beacon, October 27, 2008

Vol. 21, Issue 32, 8 pages

Campus Design: Locating a new center of international studies

FIU's campus master plan should portray an overall concept of the University's vision. Its design should represent a distinctive sense of institutional purpose. Its architecture should support the campus design in the realization of an ideal academic environment. The present master plan of Florida International University (FIU) offers neither a clear typology of architectural elements nor adequate relationships and connections between buildings. FIU needs to enhance its master plan with an architectural and urban vocabulary that creates a better environment. This thesis will examine FIU's present master plan, explaining the history of its development. Further, it will critically examine the quality of the campus, highlighting the success and failure of its various parts. The unrealized potential of the campus' original vision will be juxtaposed to the built reality. In addition, FlU's planning strategies will be parallel with the planning of several master plans of American universities. Finally, this thesis will propose a set of criteria for the inclusion of a new building in the campus master plan. The Center of International Study will be the catalyst that would bring into focus the university's vision. As a means to prove the validity of these criteria, a new location for the center of international studies will be selected, and a schematic architectural proposal will be made.

Global compilation of benthic data sets I

Approaches to quantify the organic carbon accumulation on a global scale generally do not consider the small-scale variability of sedimentary and oceanographic boundary conditions along continental margins. In this study, we present a new approach to regionalize the total organic carbon (TOC) content in surface sediments (<5 cm sediment depth). It is based on a compilation of more than 5500 single measurements from various sources. Global TOC distribution was determined by the application of a combined qualitative and quantitative-geostatistical method. Overall, 33 benthic TOC-based provinces were defined and used to process the global distribution pattern of the TOC content in surface sediments in a 1°x1° grid resolution. Regional dependencies of data points within each single province are expressed by modeled semi-variograms. Measured and estimated TOC values show good correlation, emphasizing the reasonable applicability of the method. The accumulation of organic carbon in marine surface sediments is a key parameter in the control of mineralization processes and the material exchange between the sediment and the ocean water. Our approach will help to improve global budgets of nutrient and carbon cycles.

Comparative Administrative Reform: The Rhetoric and Reality of the Civil Service Reform Programs in Uganda and Tanzania

Administrative reform is a challenging endeavor for both developed and developing countries alike. For developing countries, the challenge is greater because numerous reforms are implemented concurrently sometimes under conditions of resource scarcity and political instability. So far there is no consensus as to what makes some reforms succeed and others fail. The current study seeks to fill that gap by offering an empirical comparative analysis of the administrative reforms initiated in Uganda and Tanzania since the early 1990s. The purpose of the study is to explain the similarities and differences, and give reasons for the successes and failures of the reform programs in the two countries. It focuses on four major areas; the size of the civil service, pay reform, capacity building, and ethics and accountability. Data were collected via in-depth face to face interviews with 35 key government officials and the content analysis of various documents. The results indicate that the reforms generated initial substantial reduction in the size of the public services in both countries. In Uganda, the traditional civil service was reduced from 140,500 in 1990 to 41,730 in 2004; while in Tanzania Ministries, Departments, and Agencies were reduced by 25%. Pay reform has generated substantial increases in civil servants’ salaries in both countries but in Uganda, the government has not been able to abide by the pay strategy while in Tanzania the strategy guides the increments. Civil Service capacity building efforts have focused on enhancing the skills of the personnel. Training needs assessments were undertaken in all ministries in Uganda and a training policy was formulated. In Tanzania, the training needs assessments are still under way and a training policy has not yet been developed. Ethics and accountability are great challenges in both countries, but in Tanzania, there is more political will and commitment to improve the integrity of the civil service. The findings reveal that although Uganda started the reform with much more rigor and initial success, Tanzania has surpassed it and has a more stable, consistent, and promising reform record. This is because Uganda’s leadership lacks political legitimacy. The country has since the late 1990s experienced a civil war in the northern and western parts of the country while Tanzania has benefitted from relative peace and high level political legitimacy.

He isotope, U/Th isotope, Calcium carbonate, biogenic opal, rare earth element concentrations, and grain size distribution measured on core-top sediments during SONNE cruise SO202 (INOPEX)

Eolian dust is a significant source of iron and other nutrients that are essential for the health of marine ecosystems and potentially a controlling factor of the high nutrient-low chlorophyll status of the Subarctic North Pacific. We map the spatial distribution of dust input using three different geochemical tracers of eolian dust, 4He, 232Th and rare earth elements, in combination with grain size distribution data, from a set of core-top sediments covering the entire Subarctic North Pacific. Using the suite of geochemical proxies to fingerprint different lithogenic components, we deconvolve eolian dust input from other lithogenic inputs such as volcanic ash, ice-rafted debris, riverine and hemipelagic input. While the open ocean sites far away from the volcanic arcs are dominantly composed of pure eolian dust, lithogenic components other than eolian dust play a more crucial role along the arcs. In sites dominated by dust, eolian dust input appears to be characterized by a nearly uniform grain size mode at ~4 µm. Applying the 230Th-normalization technique, our proxies yield a consistent pattern of uniform dust fluxes of 1-2 g/m**2/yr across the Subarctic North Pacific. Elevated eolian dust fluxes of 2-4 g/m**2/yr characterize the westernmost region off Japan and the southern Kurile Islands south of 45° N and west of 165° E along the main pathway of the westerly winds. The core-top based dust flux reconstruction is consistent with recent estimates based on dissolved thorium isotope concentrations in seawater from the Subarctic North Pacific. The dust flux pattern compares well with state-of-the-art dust model predictions in the western and central Subarctic North Pacific, but we find that dust fluxes are higher than modeled fluxes by 0.5-1 g/m**2/yr in the northwest, northeast and eastern Subarctic North Pacific. Our results provide an important benchmark for biogeochemical models and a robust approach for downcore studies testing dust-induced iron fertilization of past changes in biological productivity in the Subarctic North Pacific.