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Relationship Between Water Transparency And Species Richness Of Surviving Haplochromines In Selected Habitats In Mwanza Gulf - Lake Victoria, Hdj Mrosso, Bs Msuku, O Seehausen

Tanzania Journal of Science

Several of the surviving haplochromine species have been recorded in habitats of different water transparencies within the Mwanza Gulf. Sampling for the haplochromines was carried out in muddy, rocky, sandy and vegetated habitats. All of the recorded species had been reported previously. Fewer species were encountered than previously reported in the same sampling stations. There was evidence for positive correlation between species richness and water transparency that was reinforced with data on ecological differentiation. Further exploration and conservation measures of diversity have been suggested for Lake Victoria haplochromines.

Preparations Of Spherical Polymeric Particles From Tanzanian Cashew Nut Shell Liquid By Suspension Polymerization, L L Mkayula, Y M M Makame, T H Matechi

Tanzania Journal of Science

Spherical Polymeric Particles (SPP) have been prepared from Tanzanian Cashew Nut Shell Liquid (CNSL) by suspension polymerization technique involving either step-growth or chain- growth polymerization mechanisms. The sizes of the SPP, which ranged from 0.1 to 2.0 mm were strongly influenced by the amounts of stabilizers in polymerization recipes used. The particles showed variable surface areas, indicative of the presence of pores in some of the preparations and the highest surface area recorded was about 260 m2g-1. The particles were found to exhibit Langmuir-type adsorption isotherms with saturation capacity of about 9.0 and 44.2 mg/g for Na+ and Ca2+, respectively. …

Total Mercury Concentration In Common Fish Species Of Lake Victoria, Tanzania, J F Machiwa

Tanzania Journal of Science

Total mercury (THg) concentration was analysed in muscles of common fish species of Lake Victoria in the eastern and southern parts of the lake using cold vapour Atomic Absorption Spectrophotometric technique. Mercury concentration in all fish species was generally lower than the WHO maximum allowable concentration (500 ng/g ww) in edible fish parts. The maximum concentration of THg in Lates niloticus samples was 396 ng/g ww. Samples of Oreochromis niloticus had THg concentration ranging between <0.01 and 419 ng/g ww. Clarias gariepinus had THg concentration ranging between 1.2 and 239.1 ng/g ww. All less common fish species, such as, Labeo victirianus, Synodontis victoriae, Oreochromis leucostictus, Schilbe intermedius, Brycinus jacksonii, B. sadleri, Tilapia rendalii, Tilapia zilii and Haplochromines had THg concentration below the WHO maximum allowable limit (500 ng/g ww). The study showed that Hg from small-scale gold mining activities in Lake Victoria basin is not transported to the lake by fluvial discharge. Other possible pathways of Hg input to Lake Victoria are discussed.

Contamination Of Water And Sediments By Obsolete Pesticides At Vikuge Farm, Kibaha Distric, Tanzania, M J Mihale, M A Kishimba

Tanzania Journal of Science

Sediments and water from Vikuge State Farm, Coast Region, Tanzania, where, in 1986, a “donation” of 170 m3 of partially expired pesticides were stored in an open shed- which eventually collapsed, were analysed for 80 different pesticide residues and metabolites. DDT and HCH, two of the most persistent organochlorines pesticides, were the most dominant pesticides found in both matrices. In sediments the levels were up to 99,620 mg/kg dry weight of ΣDDT and up to 7,400 mg/kg dry weight of ΣHCH. The mean total HCH concentrations were 0.95 μg/l in tap water, 0.28 mg/l in surface water and 3.09 μg/l …

Studies On The Fisheries And Biology Of Oreochromis Urolepsis (Pisces: Cichilidae) In The Mtera Resorvoir (Tanzania), F M M Chale

Tanzania Journal of Science

The fisheries and some aspects of the biology of Oreochromis urolepis of the Mtera Reservoir (Tanzania) were examined in August 2002. It was observed that there was no proper management of the reservoir's fisheries. Beach seine fishing dominated the fishery. Nearly all the O. urolepis caught by this type of gear were juveniles. The number of fish caught by the beach seines was very high, some times up to 4,000 fish per haul. The beach seines also destroy the spawning sites for the tilapias. Mean total lengths of O. urolepis caught in gillnets of legal mesh sizes (ranging from 88 …

Performance Analysis Of Cdma-Based Wireless Communication Systems Using The Simplified Improved Gaussian Approximation Method, H N Kundaeli

Tanzania Journal of Science

The limitations initially prevalent in CDMA-based systems have been gradually solved thereby making CDMA a very promising access mode for future communication systems. Following the move towards higher data transmission rates, however, a number of other problems have emerged that need to be tackled. As a result, current world-wide research on CDMA-based systems is geared towards high speed, highly mobile multimedia communication applications. In this paper, the performance of a multi-user DS-CDMA communication system operating in a Rayleigh fading environment is investigated. Performance expressions are derived and the variation of the performance with various system parameters is presented.

Physical And Chemical Characteristics Of Water In Selected Locations In Lake Victoria, Tanzania, M A Kishe

Tanzania Journal of Science

A study conducted during the period of March/April 2002 aimed at measuring physical and chemical parameters in Tanzanian portion of Lake Victoria. Temperature and conductivity values were homogeneous among and within the study stations. Levels of dissolved oxygen (DO) ranged from 4 - 9 mgl-1 and there was significant difference between stations (P < 0.05). Water transparency was poor (< 2 m secchi depth) and differed from one sampling station to another. Ammonium nitrogen (NH4+-N), with few exceptions, showed the highest concentrations both at the bottom and near-surface followed by total phosphates (TP), nitrate nitrogen (NO2+NO3--N), nitrite nitrogen (NO2--N) and Soluble Reactive Silicon (SRSi). Concentrations of NH4+-N, TP and SRSi were high at bottom waters and the reverse was true for NO2+NO3--N and NO2--N. Differences in nutrients and physical water parameters among sampling stations were statistically significant (P < 0.05). However, temperature and nutrient levels at studied areas were higher than that of 50 years ago and the trend reversed for DO and transparency. This indicates that Lake Victoria is receiving organic materials from the catchment area leading to the decline of water quality. Long-term efforts for rehabilitation, conservation and sustainable management of the lake are suggested.

Analysis Of Oligonucleotide Array Experiments With Repeated Measures Using Mixed Models, Hao Li, Constance L. Wood, Thomas V. Getchell, Marilyn L. Getchell, Arnold J. Stromberg

Statistics Faculty Publications

BACKGROUND: Two or more factor mixed factorial experiments are becoming increasingly common in microarray data analysis. In this case study, the two factors are presence (Patients with Alzheimer's disease) or absence (Control) of the disease, and brain regions including olfactory bulb (OB) or cerebellum (CER). In the design considered in this manuscript, OB and CER are repeated measurements from the same subject and, hence, are correlated. It is critical to identify sources of variability in the analysis of oligonucleotide array experiments with repeated measures and correlations among data points have to be considered. In addition, multiple testing problems are more …

The Weekly Challenger, December 30, 2004, The Weekly Challenger, Et Al

Weekly Challenger Newspaper Collection

The December 30, 2004, issue of The Weekly Challenger.

Assessment Of The Accuracy Of Approximate Methods In The Analysis Of Plane Frame Structures, I Rubaratuka

Tanzania Journal of Engineering and Technology (TJET)

pproximaic methods of analysis are widely used in the analysis OJ' frames for preliminary design due to their simplicily as compared to exact analysis meth o ds Ough they a re nol as accurate. In this paper. the methods Of hinges and portal frame are described and have been used to analyze a statically indeterminate frame by taking inro account the bending stiffness of the frame members. The obtained results are comparable Io the magnitudes of forces determined by exact methods Of analysis.

Transmission Of Neospora Caninum Between Wild And Domestic Animals, L.F.P. Gondim, M.M. Mcallister, N.E. Mateus-Pinilla, W.C. Pitt, L. D. Mech, M.E. Nelson

United States Department of Agriculture Wildlife Services: Staff Publications

To determine whether deer can transmit Neospora caninum, brains of naturally infected white-tailed deer (Odocoileus virginianus) were fed to 4 dogs; 2 of these dogs shed oocysts. Oocysts from 1 of the dogs were tested by polymerase chain reaction and found to be positive for N. caninum and negative for Hammondia heydorni. The internal transcribed spacer 1 sequence of the new strain (designated NC-deer1) was identical to N. caninum from domestic animals, indicating that N. caninum is transmitted between wild and domestic animals, often enough to prevent divergent evolution of isolated populations of the parasite. NC-deer1 …

The Icdm Development Toolkit: Technical Description, Russell Leighton, Lakshmi Vempati, Alan Davis, Mark Porczak, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

This report provides a technical description of the Integrated Cooperative Decision-Making (ICDM) software toolkit for the development of intelligent decision-support applications. An overview of the transformational forces that have precipitated the need for a development toolkit capable of supporting a distributed, information-centric software environment, and the objectives of ICDM are contained in a companion CDM Technical Report (CDM-16-04) entitled: “The ICDM Development Toolkit: Purpose and Overview”.

ICDM is an application development framework and toolkit for distributed decision-support systems incorporating software agents that collaborate with each other and human users to monitor changes (i.e., events) in the state of problem situations, …

Influence Of Hydraulic Property Correlation On Predicted Dense Nonaqueous Phase Liquid Source Zone Architecture, Mass Recovery And Contaminant Flux, Lawrence D. Lemke, Linda M. Abriola, John R. Lang

Environmental Science and Geology Faculty Research Publications

Organic liquid saturation distributions resulting from a simulated tetrachloroethene (PCE) spill were generated with alternative models of spatially varying aquifer properties for a statistically homogeneous, nonuniform sand aquifer. The distributions were analyzed to quantify DNAPL source zone characteristics and then incorporated as initial conditions for simulated PCE recovery using surfactant-enhanced aquifer remediation (SEAR). The predicted evolution of the spatial distribution of DNAPL saturations or source zone ‘‘architectures’’ and associated remediation efficiencies are strongly influenced by the spatial correlation of aquifer parameters and multiphase flow constitutive relationships. Model predictions suggest that removal of 60 to 99% of entrapped PCE can reduce …

Cofactor Fingerprinting With Std Nmr To Characterize Proteins Of Unknown Function: Identification Of A Rare Ccmp Cofactor Preference, Huili Yao, Daniel Sem

Chemistry Faculty Research and Publications

Proteomics efforts have created a need for better strategies to functionally categorize newly discovered proteins. To this end, we have employed saturation transfer difference NMR with pools of closely related cofactors, to determine cofactor preferences. This approach works well for dehydrogenases and has also been applied to cyclic nucleotide‐binding proteins. In the latter application, a protein (radial spoke protein‐2, RSP2) that plays a central role in forming the radial spoke of Chlamydomonas reinhardtii flagella was shown to bind cCMP. cCMP‐binding proteins are rare, although previous reports of their presence in sperm and flagella suggest that cCMP may have a more …

Leptonic Cp Violation In A Two Parameter Model, Joseph Schechter, Samina S. Masood, Salah Nasri

Physics - All Scholarship

We further study the "complementary" Ansatz, Tr(M_\nu)=0, for a prediagonal light Majorana type neutrino mass matrix. Previously, this was studied for the CP conserving case and the case where the two Majorana type CP violating phases were present but the Dirac type CP violating phase was neglected. Here we employ a simple geometric algorithm which enables us to "solve" the Ansatz including all three CP violating phases. Specifically, given the known neutrino oscillation data and an assumed two parameter (the third neutrino mass m_3 and the Dirac CP phase \delta) family of inputs we predict the neutrino masses and Majorana …

Exploring The Optimal Sensitivity Of Sum-Variance Nonseparability Criteria For Spin-1/2 Systems, Irfan Ali Khan, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We report on experimental and theoretical studies on recently introduced entanglement measures which use a sum of spin-variance criteria for two spin-1∕2 particles. Three inequalities are explored which exhibit useful concatenating properties. They are each shown to have greater sensitivities than a Bell’s measurement, while each requiring fewer measurements than a Bell’s measurement to obtain. The simplest inequality, requiring just four measurements, is shown to be efficient at testing for entanglement in down-conversion sources which naturally exhibit maximally polarized noise. The most complex inequality, requiring just 12 measurements, is shown to have a sensitivity equal to that of the Peres …

Murray Ledger And Times, December 27, 2004, Murray Ledger And Times

The Murray Ledger & Times

No abstract provided.

Summertime Ozone At Mount Washington: Meteorological Controls At The Highest Peak In The Northeast, E V. Fischer, R. Talbot, Jack E. Dibb

Earth Sciences

This study examined the synoptic and regional-scale meteorological controls on summertime O₃ at Mount Washington, the highest peak (1910 m) in the northeastern United States. Analysis of air mass transport to Mount Washington was conducted for the summers of 1998–2003 using backward trajectories. Distinct patterns in air mass history were revealed using this approach that helped explain extreme variations in O₃ mixing ratios. Most enhanced (≥90th percentile) and depleted (≤10th percentile) O₃ events were short-lived and spread out over the summer months. Enhanced O₃ events at Mount Washington were generally associated with westerly transport, while depleted …

Snow Accumulation, Surface Height Change, And Firn Densification At Summit, Greenland: Insights From 2 Years Of In Situ Observation, Jack E. Dibb, Mark Fahnestock

Earth Sciences

Weekly measurements of surface height change were made at an accumulation forest of 100 stakes at Summit, Greenland, over a 2-year period (17 August 2000 to 8 August 2002). On average, the surface height relative to the stakes increased 64 (±4.8) cm in the first year and 65 (±5.3) cm in the second, identical to the average (65 ± 4.5 cm yr⁻¹) previously reported for the period 1991–1995 in a similar forest 28 km to the southwest. The continuous 2-year data set indicates that the rate of surface rise was not constant, with the summers of 2001 and …

Employment Discrimination In A High Velocity Labor Market, Alan Hyde

Rutgers Law School (Newark) Faculty Papers

Silicon Valley employers employ few African-Americans, Latino/as, or older workers, yet do not fit the usual paradigms of employment discrimination: they exhibit no taste for uniformity and do not employ job tournaments or internal labor markets. A new model of employment discrimination attributes disparate hiring in Silicon Valley to a combination of: demands for specific skill sets at hiring (the opposite of the subjective criteria that have long beguiled scholars of discrimination) and concomitant refusal to train; hiring through networks of personal contacts; and rewards to career paths that alternate employment with self-employment. Overcoming the disparate impact of these employment …

Faculty Newsnotes 2004 No. 365, Office Of The Provost

Faculty Newsnotes (1972-2010)

No abstract provided.

More Than Teacher Directed Or Child Initiated: Preschool Curriculum Type, Parent Involvement, And Children's Outcomes In The Child-Parent Centers, Elizabeth Graue, Melissa A. Clements, Arthur J. Reynolds, Michael D. Niles

Education Policy Analysis Archives (EPAA)

This study investigated the contributions of curriculum approach and parent involvement to the short- and long-term effects of preschool participation in the Title I Chicago Child-Parent Centers. …

Education Policy Analysis Archives 12/72 , Arizona State University, University Of South Florida

College of Education Publications

More than Teacher Directed or Child Initiated: Preschool Curriculum Type, Parent Involvement, and Children, Äôs Outcomes in the Child-Parent Centers / Elizabeth Graue, Melissa A. Clements, Arthur J. Reynolds [and] Michael D. Niles.

Pseudorapidity Asymmetry And Centrality Dependence Of Charged Hadron Spectra In D+Au Collisions At √SNn=200 Gev, Star Collaboration, T.D. Gutierrez

Physics

The pseudorapidity asymmetry and centrality dependence of charged hadron spectra in d+Au collisions at √s_NN=200 GeV are presented. The charged particle density at midrapidity, its pseudorapidity asymmetry, and centrality dependence are reasonably reproduced by a multiphase transport model, by HIJING, and by the latest calculations in a saturation model. Ratios of transverse momentum spectra between backward and forward pseudorapidity are above unity for p_T below 5GeV ∕ c. The ratio of central to peripheral spectra in d+Au collisions shows enhancement at 2 < p_T < 6GeV ∕ c, with a larger effect at backward rapidity than forward rapidity. Our measurements are in qualitative agreement with gluon saturation and in contrast to calculations based on incoherent multiple partonic scatterings.

Advisory Circular: Reporting Wildlife Aircraft Strikes, J.R. White

Other Bird Strike and Aviation Materials

This Advisory Circular (AC) explains the importance of reporting collisions between aircraft and wildlife, more commonly referred to as wildlife strikes. It also examines recent improvements in the Federal Aviation Administration’s (FAA) Bird/Other Wildlife Strike Reporting system; how to report a wildlife strike; what happens to the wildlife strike report data; how to access the FAA National Wildlife Aircraft Strike Database; and the FAA’s Feather Identification program.

Global Asymptotic Controllability Implies Input-To-State Stabilization, Michael Malisoff, Ludovic Rifford, Eduardo Sontag

Faculty Publications

The main problem addressed in this paper is the design of feedbacks for globally asymptotically controllable (GAC) control affine systems that render the closed-loop systems input-to-state stable (ISS) with respect to actuator errors. Extensions for fully nonlinear GAC systems with actuator errors are also discussed. Our controllers have the property that they tolerate small observation noise as well.

Fixed-Connectivity Membranes, Mark Bowick

Physics - All Scholarship

The statistical mechanics of flexible surfaces with internal elasticity and shape fluctuations is summarized. Phantom and self-avoiding isotropic and anisotropic membranes are discussed, with emphasis on the universal negative Poisson ratio common to the low-temperature phase of phantom membranes and all strictly self-avoiding membranes in the absence of attractive interactions. The study of crystalline order on the frozen surface of spherical membranes is also treated.

Secure Context-Sensitive Authorization, Kazuhiro Minami, David Kotz

Computer Science Technical Reports

There is a recent trend toward rule-based authorization systems to achieve flexible security policies. Also, new sensing technologies in pervasive computing make it possible to define context-sensitive rules, such as ``allow database access only to staff who are currently located in the main office.'' However, these rules, or the facts that are needed to verify authority, often involve sensitive context information. This paper presents a secure context-sensitive authorization system that protects confidential information in facts or rules. Furthermore, our system allows multiple hosts in a distributed environment to perform the evaluation of an authorization query in a collaborative way; we …

Structural Properties Of Discs And Bulges Of Early-Type Galaxies, Roelof S. De Jong, Luc Simard, Roger L. Davies, R. P. Saglia, David Burstein, Matthew Colless, Robert Mcmahan, Gary Wegner

Dartmouth Scholarship

We have used the EFAR sample of galaxies to investigate the light distributions of early-type galaxies. We decompose the two-dimensional light distribution of the galaxies in a flattened spheroidal component with a Sérsic radial light profile and an inclined disc component with an exponential light profile. We show that if we assume that all galaxies can have a spheroidal and a disc component, then the brightest, bulge-dominated elliptical galaxies have a fairly broad distribution in the Sérsic profile shape parameter n_B, with a median of approximately 3.7 and with σ∼ 0.9. Other galaxies have smaller n_B values. …

Taking Back The Law School Classroom: Using Technology To Foster Active Student Learning, Paul L. Caron, Rafael Gely

Journal of Legal Education

No abstract provided.