Detection of cryptosporidium oocysts in water and environmental concentrates

Whilst current methods for the isolation and enumeration of Cryptosporidium spp. oocysts in water have provided some insight into their occurrence and significance, they are regarded as being inefficient, variable and time-consuming, with much of the interpretation being left to the expertise of the analyst. Two expectations of novel developments are to reduce the variability and subjectivity associated with the isolation and identification of oocysts. Flocculation, immunomagnetisable and flow cytometric techniques, for concentrating oocysts from water samples, should prove more reliable than current methods, whilst the development of more avid and specific monoclonal antibodies in conjunction with the use of nuclear fluorochromes will aid identification. Further insight into the viability, taxonomy, species identification, infectivity and virulence of the parasite should be forthcoming through the use of techniques such as the polymerase chain reaction, in situ hybridisation and non-uniform alternating current electrical fields. Such information is necessary in order to enable microbiologists, epidemiologists, engineers, utility operators and regulators to assess the safety of a water supply, with respect to Cryptosporidium contamination, more effectively

Characterization of a planar microcoil for implantable microsystems

This paper discusses the modelling, design and characterization of planar microcoils to be used in telemetry systems that supply energy to miniaturized implants. Parasitic electrical effects that may become important at a.c. frequencies of several megahertz are evaluated. The fabrication process and electrical characterization of planar receiver microcoils will be described, and it will be shown that a power of a few milliwatts is feasible.\u

A digital multi-channel spectroscopy system with 100 MHz flash ADC module for the GENIUS-TF and GENIUS projects

In this paper we will present the first results of applying a digital processing technology in low-level gamma spectroscopy with HPGE detectors. An experimental gamma spectrometer using Flash ADC module is built and tested. The test system is now under development and shows major advantages over the traditional analog technologies. It will be installed for the GENIUS-TF and GENIUS projects in Gran-Sasso in early 2003.Comment: 8 pages, latex, 6 figures, Published in NIM, Volume 498, Issues 1-3, Pages 334-339, also see Home Page of Heidelberg Non-Accelerator Particle Physics Group: http://www.mpi-hd.mpg.de/non_acc

User guide for the BGS UK Coal Resource for New Exploitation Technologies (Version 1) dataset

This report describes the Coal for New Technologies GIS dataset, which is a suite of data layers developed in 2004 by the British Geological Survey (BGS), with the assistance of Wardell Armstrong and Imperial College, London. The principle aim of the original study was to develop a methodology to assess the potential of the UK onshore coal resources for both exploitation by conventional (mining) and new technologies. Digital data was created using a Geographic Information System (GIS) to produce the delivered output of the original project, a series of paper maps that would identify prospective areas. The Coal for New Technologies digital data has been derived from the original source data. No updating has been carried out and has been published in its original format under Open Government Licence as a set of data layers covering mining technologies: Mining Technologies: Area with technical potential for opencast workings (source Coal Resource Map of Great Britain BGS/Coal Authority 1999) Underground mining exploration prospects Good prospects for abandoned mine methane (AMM) (Mine workings not recovered) Resource area for coal mine methane (CMM) (source Coal Authority Underground Licences, May 2002) Extent of underground workings with 500m buffer zone (based on Coal Authority data, May 2002) New Technologies: Area greater than 1200m from surface with potential for CO2 sequestration Area with good coalbed methane (CBM) potential Underground coal gasification (UCG) potential Coalbed methane (CBM) resource area Coal-bearing strata The original methodology is described in the project report which outlines the assessment, development and uncertainties of the methodology which is available as a free download on the BGS website here: http://www.bgs.ac.uk/downloads/start.cfm?id=1712

Epidemiology of diarrhoeal disease in rural Malawi - a case study of cryptosporidiosis

A rural community based case control study was conducted in Malawi, over a 23 month period, to identify determinants influencing human cryptosporidiosis in under fives. 96 home interviews were conducted in 24 communities (cases n=24; unmatched controls n=72). 61 risk factors were investigated by questionnaire, combined with quantitative data from drinking water and domesticated animal stool samples. Cryptosporidium oocysts were not detected in either sample type. Multivariate logistic regression of questionnaire data revealed an increased risk of cryptosporidiosis associated with ownership of pigs (OR7.2, 95%CI 1.9–27.5, p=0.004), presence of diarrhoea in the household (OR8.8, 95%CI 1.8–53.4, p=0.008), bathing in the river (OR76.7, 95%CI 1.1–23.8, p=0.037) and no education within the household (OR3.6, 95%CI 1.1–11.8, p=0.038). Bacteriological results indicating faecal contamination of both drinking water stored within the home, and the surface of guardians’ hands were indicative of poor hygienic practices and potential sources of infection

Some remarks about pseudo gap behavior of nearly antiferromagnetic metals

In the antiferromagnetically ordered phase of a metal, gaps open on parts of the Fermi surface if the Fermi volume is sufficiently large. We discuss simple qualitative and heuristic arguments under what conditions precursor effects, i.e. pseudo gaps, are expected in the paramagnetic phase of a metal close to an antiferromagnetic quantum phase transition. At least for weak interactions, we do not expect the formation of pseudo gaps in a three dimensional material. According to our arguments, the upper critical dimension d_c for the formation of pseudo gaps is d_c=2. However, at the present stage we cannot rule out a higher upper critical dimension, 2 < d_c <= 3. We also discuss briefly the role of statistical interactions in pseudo gap phases.Comment: 6 pages, accepted in PRB, relevant references added, several small change

Capturing Data Provenance from Statistical Software

We have created tools that automate one of the most burdensome aspects of documenting the provenance of research data: describing data transformations performed by statistical software.&nbsp; Researchers in many fields use statistical software (SPSS, Stata, SAS, R, Python) for data transformation and data management as well as analysis.&nbsp; The C2Metadata ("Continuous Capture of Metadata for Statistical Data") Project creates a metadata workflow paralleling the data management process by deriving provenance information from scripts used to manage and transform data.&nbsp; C2Metadata differs from most previous data provenance initiatives by documenting transformations at the variable level rather than describing a sequence of opaque programs.&nbsp; Command scripts for statistical software are translated into an independent Structured Data Transformation Language (SDTL), which serves as an intermediate language for describing data transformations.&nbsp;&nbsp; SDTL can be used to add variable-level provenance to data catalogues and codebooks and to create "variable lineages" for auditing software operations.&nbsp;&nbsp; Better data documentation makes research more transparent and expands the discovery and re-use of research data

Chromosomal deletions on 16p11.2 encompassing SH2B1 are associated with accelerated metabolic disease.

New approaches are needed to treat people whose obesity and type 2 diabetes (T2D) are driven by specific mechanisms. We investigate a deletion on chromosome 16p11.2 (breakpoint 2-3 [BP2-3]) encompassing SH2B1, a mediator of leptin and insulin signaling. Phenome-wide association scans in the UK (N = 502,399) and Estonian (N = 208,360) biobanks show that deletion carriers have increased body mass index (BMI; p = 1.3 × 10 &lt;sup&gt;-10&lt;/sup&gt; ) and increased rates of T2D. Compared with BMI-matched controls, deletion carriers have an earlier onset of T2D, with poorer glycemic control despite higher medication usage. Cystatin C, a biomarker of kidney function, is significantly elevated in deletion carriers, suggesting increased risk of renal impairment. In a Mendelian randomization study, decreased SH2B1 expression increases T2D risk (p = 8.1 × 10 &lt;sup&gt;-6&lt;/sup&gt; ). We conclude that people with 16p11.2 BP2-3 deletions have early, complex obesity and T2D and may benefit from therapies that enhance leptin and insulin signaling

Local fluctuations in quantum critical metals

We show that spatially local, yet low-energy, fluctuations can play an essential role in the physics of strongly correlated electron systems tuned to a quantum critical point. A detailed microscopic analysis of the Kondo lattice model is carried out within an extended dynamical mean-field approach. The correlation functions for the lattice model are calculated through a self-consistent Bose-Fermi Kondo problem, in which a local moment is coupled both to a fermionic bath and to a bosonic bath (a fluctuating magnetic field). A renormalization-group treatment of this impurity problem--perturbative in $\epsilon=1-\gamma$, where $\gamma$ is an exponent characterizing the spectrum of the bosonic bath--shows that competition between the two couplings can drive the local-moment fluctuations critical. As a result, two distinct types of quantum critical point emerge in the Kondo lattice, one being of the usual spin-density-wave type, the other ``locally critical.'' Near the locally critical point, the dynamical spin susceptibility exhibits $\omega/T$ scaling with a fractional exponent. While the spin-density-wave critical point is Gaussian, the locally critical point is an interacting fixed point at which long-wavelength and spatially local critical modes coexist. A Ginzburg-Landau description for the locally critical point is discussed. It is argued that these results are robust, that local criticality provides a natural description of the quantum critical behavior seen in a number of heavy-fermion metals, and that this picture may also be relevant to other strongly correlated metals.Comment: 20 pages, 12 figures; typos in figure 3 and in the main text corrected, version as publishe

High-purity germanium detector ionization pulse shapes of nuclear recoils, gamma interactions and microphonism

Nuclear recoil measurements with high-purity Germanium detectors are very promising to directly detect dark matter candidates. The main background sources in such experiments are natural radioactivity and microphonic noise. Digital pulse shape analysis is an encouraging approach to reduce the background originating from the latter. To study the pulse shapes of nuclear recoil events we performed a neutron scattering experiment, which covered the ionization energy range from 20 to 80 keV. We have measured ionization efficiencies as well and found an excellent agreement with the theory of Lindhard. In a further experiment we measured pulse shapes of a radioactive gamma-source and found no difference to nuclear recoil pulse shapes. Pulse shapes originating from microphonics of a HPGe-detector are presented for the first time. A microphonic noise suppression method, crucial for dark matter direct detection experiments, can therefore be calibrated with pulse shapes from gamma-sources.Comment: 11 pages (latex) including 6 postscript figures and 2 table