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Metaldehyde is the active ingredient in most slug pellets used to protect crops. This molluscicide is considered an emerging pollutant and is frequently detected in surface water bodies above the EU statutory drinking water limit of 0.1 μg L−1 for a pesticide. This presents a challenge for providers of drinking water. Understanding the sources, transport and environmental fate of this compound is therefore important. This critical review discusses these aspects including monitoring and analytical techniques used for the detection of metaldehyde in environmental matrices. Novel techniques used for the removal of metaldehyde from drinking water are presented together with potential catchment management strategies and initiatives useful for the mitigation of this molluscicide in the environment.

Summary The Pm blood group system in Peromyscus maniculatus was originally described by Rasmussen as consisting of two co-dominant alleles, PmA and PmB, responsible for the antigenic characteristics A and B. This paper describes two additional antisera, anti-C and anti-X, which expand this system and show it to be serologically complex. Anti-X is comprised of antibodies directed against at least two antigenic characteristics X‘ and X“. Four and possibly six alleles are described by the four antisera. Different subspecies exhibit different spectra of alleles at the Pm locus. A segregation distortion is evidenced.

Di- and tri-peptides with α -aminopropanephosphonic acid as the acid-terminal residue have been prepared containing L-alanyl, D-alanyl, DL-alanyl, and glycyl groups. Nmr parameters (1H, 13C and 31P) are reported for solutions of the peptides in D2O and are discussed. Diastereoisomeric forms of the L-ala-, and L-ala-L-ala-peptides were separated on a cation exchange-column and it was found in each case that the methine and carbonyl groups of the alanyl residue that is adjacent to the aminophosphonic group exhibit slightly different 13C chemical shifts in each of the two diastereoisomers. Fast-atom bombardment mass spectrometry gave characteristic [MH]+ ions, which usually appeared as the base peak. Fragment ions were formed by the elimination of α-lactam units from the amino-carboxylic acid residues and phosphorous acid from the aminophosphonic acid residue. The L-ala-peptides showed similar activity to that of α-aminopropanephosphonic acid when applied as seed-dressings at 400 ppm for the control...

A range of α-amino-, ω-amino-, α-guanidino-, and ω-guanidinoalkanephosphonic acids has been prepared for the purpose of studying their spectroscopic features and fungicidal activity. In addition, α-thioureido-octanephosphonic acid and thioureylene-1,1-bis(1-octanephosphonic acid) were isolated during the preparation of α-guanidino-octanephosphonic acid. 31P, 1H, and 13C nmr spectral data which were obtained for solutions of the amino-and guanidino-compounds in D2O or D2O/D2SO4, and for the thioureido compounds in DMSO-d 6, are discussed together with previously reported data for the aminophosphonic types. FAB mass spectrometry generally gives strong pseudomolecular ions [MH]+ for the zwitterionic amino-and guanidino-compounds with relatively simple fragmentations. Fungicidal activity of the α-aminophosphonic acids was found to be greater than for the ω-amino compounds, with maximum activity at a chain length of three carbon atoms when used as a seed dressing for the control of Drechslera spp. Mod...

The GridPP Collaboration is building a UK computing Grid for particle physics, as part of the international effort towards computing for the Large Hadron Collider. The project, funded by the UK Particle Physics and Astronomy Research Council (PPARC), began in September 2001 and completed its first phase 3 years later. GridPP is a collaboration of approximately 100 researchers in 19 UK university particle physics groups, the Council for the Central Laboratory of the Research Councils and CERN, reflecting the strategic importance of the project. In collaboration with other European and US efforts, the first phase of the project demonstrated the feasibility of developing, deploying and operating a Grid-based computing system to meet the UK needs of the Large Hadron Collider experiments. This note describes the work undertaken to achieve this goal. © 2006 IOP Publishing Ltd.

In a world-wide computational Grid, users typically want their jobs to be executed as fast as possible, while the goal of a Grid infrastructure is to assure specific quality of service for all users. In order to reconcile these apparently contrasting goals, the authors proposed an economy-based strategy to be used in a Data Grid for efficient access to and distribution of data replicas needed by Grid jobs [20]. The strategy is based on an economic model where data-seeking agents negotiate optimal prices for exchanging data files with data-storing agents. Data-storing agents also try to keep on their Grid sites the most useful files. In previous works, performance of the economic model has been empirically studied via simulations conducted using the Data Grid simulator OptorSim [11,18]. In this paper the problem of efficient access to and distribution of replicas is introduced and the economic model is described. A formalisation of the auction protocol basis of the economic model is then presented and formal proof of some properties (namely, that it is deadlock-free and always terminates) is provided. The auction protocol is modelled using Petri nets, a formal and graphical language that is well suited for modelling concurrent distributed systems. © 2005 - IOS Press and the authors.

Aminophosphonic acids and related derivatives have previously attracted attention as possible plant-growth regulators and for their potential as herbicides. We have now shown that a number of amino-alkanephosphonic acids of the general type (HO)2P(O)CR3R4 (CH2)n NR1R2have useful fungicidal activity, eapecially for agricultural use (1). Arising from extensive laboratory tests and field triala α-aminopropanephosphonic acid (code number PNL 62) has been developed for commercial application under the draft common name ampropylfos. This new pesticide is especially useful primarily as a seed-dresaing agent for the control of Drechslera teres. Both R- and S-isomers are active. The compound shows no phytotoxic activity and is of very low mammalian toxicity (LD50 > 5000 mg kg−1). Within the series of aminophosphonic acids investigated, activity was greatest when the amino group is in the alpha position. Activity decreased with increasing branching in the alkyl chain and was removed by the presence of vari...

Protein products of 24 loci from the genomes of Yellowstone Park elk were analyzed by electrophoresis. Heterozygosity was detected in only one system, making elk much less polymorphic than eastern whitetailed deer. Data for several other large mammals are compared with those for elk and reveal similarly low levels of isozymic variation. The data are consistent with the fine-grained niche theory but difficult to reconcile with bottlenecks and genetic drift.

The infrared absorption spectra and corresponding dispersion spectra of the following liquids have been measured over the range 4200 to 250 cm−1: cyclo-C5H10, CH3·NO2, CH3·CN, CH2Br2, CH2Cl2, CBrCl3, CCl4, C6H6, C6H5·CH3, C6H5Cl, C6H5Br, C6H5I, and C6F6. The spectra were measured in the absence of solvent and the results are reported as the real and imaginary components of the complex refractive index ( n, k). The experimental technique combines transmission measurements through thin films and attenuated total reflection measurements by a method which has been described previously. The complete spectral and dispersion curves are displayed graphically; the absorption maxima are tabulated as absorption indices ( kmax) and as molar absorption coefficients (εmax). The dispersion extrema ( nmin, nmax) are also listed and the experimental uncertainties in these quantities are evaluated. Provision is made to supply the complete optical constant data on magnetic tape at encoded intervals of 0.5 cm−1.

Spectroscopic data from a var iety of analyt ical techniques such as x-ray diffraction (XRD), infrared (IR) and Raman spectroscopies, secondary ion mass spectrometry (SIMS) and energy dispersive X-ray analysis (EDX) can be obtained from small areas of samples (< 1 mm2) through the use of microscope sampling accessories. If provisions are made to scan or translate the sample, then a spectrum that is characteristic of each region of interest can be obtained. Alternatively, selective area detectors eliminate the requirement for scanning the sample. Extract ion of information about a specific energy band from each spectrum allows elucidat ion of the spatial distribution of the feature giving rise to that band. For example, the distribution of a compound could be imaged by extracting the intensity of an IR band or XRD peak due to that compound. Peak posit ion and peak width are other parameters that can be extracted as a function of posit ion. Similarly, elemental distributions could be obtained using SIMS and EDX.

An improved technique is described for the determination of the optical constants of liquids in the infrared. It is based on a combination of transmission and attenuated total reflection (ATR) measurements. A novel application of the Kramers-Kronig transform function is involved whereby a single-valued integration constant is derived from a vector of refractive index measurements obtained by ATR. These are measured over a wavenumber range where the absorbance is low. It has been shown in earlier work that by an appropriate choice of a low refractive index contact material (in our case sodium chloride) the ATR method has high precision and accuracy under these conditions. The accuracy of the method is evaluated on the basis of a statistical treatment of the propagation of the estimated errors in the experimentally measured quantities, viz., the transmittance, the cell thickness, and the ATR measurements which establish the integration constant (anchor point) of the Kramers-Kronig transform function. The transmittance measurements are made at several cell thicknesses. The data reduction computer program, by which the optical constants are evaluated from the transmission measurements, monitors these sets of data and selects at each wavenumber the one having the minimal statistical error.

An electrophoretic survey of 26 loci in rainbow trout Salmo gairdneri inhabiting a geothermally heated stream, the Firehole River of Yellowstone National Park, Wyoming revealed no unique ecotypes along a temperature gradient. Average heterozygosities (H) from two stations along the gradient were 0.036 and 0.057. These were not significantly different from each other nor from a hatchery strain derived from the Ennis, Montana hatchery which stocked many of the founding fish many years earlier.

The design and construction of an infrared spectrophotometer for the quantitative measurement of attenuated total reflection spectra are described. The instrument is used to determine the optical constants of liquids as part of a study of infrared band shapes and intensities.

N-(ω-Aminoalkyl)- and N-(ω-guanidinoalkyl)-aminoalkanephosphonic acids have been prepared from α, ω-diaminoalkanes by reaction with chloromethanephosphonic acid (or an ester of a halogeno-alkanephosphonic acid), followed by treatment with S-methylisothiouronium chloride. Ethylene diamine yielded 1-phosphonomethyl-2-iminoimidazolidine. A number of 1:1 salts of the α, ω-diamines and chloromethanephosphonic acid are also reported. Doubly charged zwitterionic structures are assigned to both ω-amino and ω-guanidino compounds on the basis of 31P and 13C nmr data. Thus the addition of an excess of acid (D2SO4) causes the 31P chemical shift to move to higher field, from ca. 8 to 14 ppm, whilst 1 Jpc increases from ca. 130 to 150 Hz. The 1H and 13C chemical shifts of the terminal methylene groups in the polymethylene chain are unaffected by acidification. Fast atom bombardment mass spectrometry gives rise to characteristic [M + H]+ ions, frequently as the base peak, and to fragmentations involving the los...

During studies of genetic variation in natural populations of deer mice (Peromyscus maniculatus) and blue grouse (Dendragapus obscurus), we have routinely stained for serum esterase activity on starch gels. After this procedure, white bands have been found to contrast with the normal gray background of gels stained for esterase activity (Fig. 1). This new "phenotype" is common to several vertebrate species, including man. Vertical starch gel electrophoresis (Smithies, 1959) of serum was carried out using a buffer system similar to that of Poulik (1957). The electrode buffer (pH 8.6) contained 11.8 g/liter boric acid and 2.7 g/liter lithium hydroxide, and the gel buffer contained 10.7 g/liter tris, 1.2 g/liter citric acid, and 10~ electrode buffer (v:v). Approximately 10 #1 of whole serum was added to the slots in a starch slab of 32 cm by 12 cm by 3 mm. After electrophoresis for 3 hr at 2 C in a voltage gradient of 18.8 v/cm, the gels were stained for 2 hr in daylight at room temperature in the following solution: 10 ml 0.1 M tris-HC1 buffer (pH 7.0), 87.5 ml water, 2.5 ml 1 ~ ~-naphthyl acetate (w:v) in water-acetone 1:1 (v:v), and 100 mg fast blue R R salt. The clarity of the bands was sensitive to changes in the length of time of staining, the amount of light, and the concentrations of substrate and stain. After staining, the gels were fixed and washed in several changes of water: methanol: acetic acid, 5:5:1 (v:v :v). The bands became clearly visible after washing for 24-48 hr. Electrophoresis in a gel of 6 mm thickness and correspondingly lower voltage seldom produced well-defined bands, fl-Naphthyl acetate can be used as the substrate, but the bands are less easily seen because of lack of contrast.

1. The literature concerning attempts to produce macrocytic anemia of the liver-deficiency type in animals by operations on the gastrointestinal tract has been reviewed. Operations on the stomach have failed consistently to produce such an anemia, but success has been achieved by operations on the small intestine with the creation of blind loops or intestinal stenosis. 2. The technic we have used to produce macrocytic anemia in the rat is described in detail. The essentials are that the blind loop should fill with peristalsis and that it should not be too low down in the small intestine. 3. Anemia does not usually develop until an interval of several weeks or months after the operation. It is then macrocytic in type and acute in course. 4. The anemia is probably dependent on stagnation in the blind loop and a change in the bacterial flora of the small intestine.

1. The case is reported of a woman in whom a macrocytic anemia developed after a short-circuit operation for regional ileitis. At a second operation, multiple constrictions and distentions were present in the bypassed loop. 2. The literature of macrocytic anemia associated with intestinal stenosis and anastomosis is reviewed. The anemia differs from Addisonian pernicious anemia in that the gastric secretion of hydrochloric acid and intrinsic factor may be normal. There need be no steatorrhea. It is concluded that the anemia is probably due to stagnation of intestinal contents and the absorption of toxic substances. 3. The production of blind loops in the small intestine of experimental animals offers a promising approach to the study of the macrocytic anemias.

A technic for repeated femoral bone marrow biopsy in the rat is detailed. Differential counts confirmed the distribution of the cellular elements as described by other authors.

The normal values for blood counts in the adult albino rat are presented.

Administration of adriamycin and Corynebacterium parvum alone in C57BL/6J mice bearing Lewis lung carcinoma stimulated the direct (19S) and indirect (7S) plaque-forming cell (PFC) response specific for sheep red blood cells. Thus adriamycin appears to possess some immunostimulatory effect on tumor-bearing mice with much less effect than C. parvum alone. Simultaneous administration of adriamycin and C. parvum decreased the PFC response compared to that for C. parvum alone. This decrease may indicate that drug-vaccine interaction could produce some inhibition of the strong immunostimulatory effect of C. parvum as measured by the PFC response in tumor-bearing mice. The immunostimulatory effect of adriamycin and C. parvum administered as a single agent or in combination was associated with significant splenomegaly. The results of this study could be helpful in clinical situations when these agents are used alone or combined.

The physical state of membranes in the bacterium Acholeplasma laidlawii was investigated by FT-IR spectroscopy. A comparison of the temperature dependence of the infrared spectra of live and lifeless Acholeplasma laidlawii cells reveals that at the temperature of growth, i.e., 37°C, the membranes of live cells have a considerably higher degree of conformational disorder. Furthermore, the thermal response of membranes in live and lifeless cells, as monitored by various infrared spectra parameters, is shown to be quite different., Fourier and Computerized Infrared Spectroscopy, January 1, 1985, Ottawa, Canada, Series: Proceedings of SPIE

Fourier transform infrared spectroscopy is presented as a technique with great potential for the study of aqueous surfactants, especially when investigating structural changes brought about by a change in temperature or concentration. Micelle formation in aqueous surfactants can be induced by either an increase in concentration through the critical micelle concentration range, or by an increase in temperature through the critical micellization temperature. Due to the concentration range involved, (i. e. 0.1 to 0.3 M surfactant), infrared spectroscopy is particularly suitable for the study of the temperature-induced micellization, and we discuss herein details of the structural changes observed at the critical micellization temperature of a number of anionic surfactants. The thermotropic phase behavior of these aqueous surfactants was monitored via structural changes specific to the hydrophobic acyl chains and those of the hydrophilic carboxylate and sulfate head group moieties. The temperature-induced changes in infrared spectral parameters such as frequency and bandwidth characterize the critical micellization temperature of these surfactants as a phase transition from a conformationally ordered, solid-like phase to an isotropic micellar phase. The concept of a critical micellization temperature is discussed in relation to that of the Krafft point and the critical micelle concentration.

Volvulus of the intestine has recently been observed in three patients with idiopathic steatorrhea in relapse. Two patients gave a history of intermittent abdominal pain, distension and obstipation. Radiographic studies during these attacks revealed obstruction at the level of the sigmoid colon. Reduction under proctoscopic control was achieved in one instance, spontaneous resolution occurring in the other. The third patient presented as a surgical emergency and underwent operative reduction of a small intestinal volvulus. Persistence of diarrhea and weight loss postoperatively led to further investigation and a diagnosis of idiopathic steatorrhea. In all cases, treatment resulted in clinical remission with a coincident disappearance of obstructive intestinal symptoms. The pathogenesis of volvulus in sprue is poorly understood. Atonicity and dilatation of the bowel and stretching of the mesentery likely represent important factors. The symptoms of recurrent abdominal pain and distension in idiopathic steatorrhea necessitate an increased awareness of intestinal volvulus as a complication of this disease.

SUMMARYAnomalous frequencies of transferrin phenotypes were found among the offspring of matings between deer mice heterozygous for the two forms of transferrin most common in natural populations. Matings involving other phenotypes produced offspring in the expected phenotypic frequencies. Selective penetration by facility, occurring only in the reproductive tract of the heterozygous females, appears to provide the most satisfactory explanation for the observations.

Two cases of Plasmodium ovale malaria acquired in West Africa appeared as primary delayed attacks after one year's continuous residence in Canada. Both patients took full prophylactic doses of chloroquine before, during, and for several weeks after exposure. The inadequacy of the 4-aminoquinolines for protection against latent benign tertian malaria is noted, and the use of primaquine is recommended. Paroxysms occurred in the evening and were accompanied by severe muscle pain, features considered typical of ovale malaria. One patient showed electrocardiographic changes and clinical signs of cardiac malfunction; these disappeared following specific treatment for malaria. In this age of accelerated travel and international movements of people it is important that physicians in temperate regions be aware of the exotic infections of the tropics, as well as of the need for protective measures for travellers to areas where these diseases are endemic.