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Motion management strategies are important during stereotactic ablative body radiotherapy for abdominal targets. The kidney is a mobile retroperitoneal organ that moves with respiration. A review of the literature was performed to investigate the reported degree of kidney motion associated with various breathing conditions. A structured search was performed using Medline from January 1970 to May 2013 for all publications describing cranial-caudal kidney motion. Relevance to radiotherapy practice was reviewed based on any breathing instructions and/or immobilization equipment that could affect breathing pattern. Studies were categorized under three types of breathing conditions: Forced-shallow, breath-hold/deep and free. A total of 25 publications were identified describing cranial-caudal kidney motion with a combined total of 415 participants. Three publications described forced-shallow breathing using prone positioning or abdominal compression plates. Prone positioning, compared to supine positioning, did little to minimise kidney motion, however use of compression plates can result in kidney motion of less than 5 mm. Eight publications described deep breathing/breath hold techniques that showed average kidney motion ranging between 10 mm-40 mm. Fifteen publications investigated kidney motion under free breathing with the majority reporting mean motion of less than 10 mm. Kidney movement of up to 8.1 mm in the anterior posterior direction and 6.2 mm laterally were reported with no indications that breathing technique can influence the extent of this motion. In summary, kidney movement is complex and consideration should be made to ensure that motion management strategies provide the desired radiotherapy benefit. There are limited publications on the effectiveness of abdominal compression on reducing kidney motion which warrant further investigation in this area.

Condensation of the dichloride clathrochelate FeBd2(Cl2Gm)(BF)2precursor (Bd2–is the α-benzyl dioxime dianion, Gm is the glyoxime residue) with quinoxaline-2,3-dithiol in the presence of triethylamine afforded the ribbed-functionalized quinoxaline clathrochelate. The structure of this complex was established by X-ray diffraction analysis.

The reaction of phenylacetylene with CO and n-butanol in toluene (363 K) catalyzed by the Pd(dba)2/m(CF3COOH)/n(Ph3P) system (dba is dibenzylideneacetone; 2 ≤ m≤ 8; 10 ≤ n≤ 30) is studied. The initial rate of the main product (butyl 2-phenylpropenoate) buildup is found to depend on the pressure of CO and the concentrations of reactants and system components. The state of the catalyst under reaction conditions is studied in situby IR spectroscopy. A kinetic model is developed based on the experimental results. This model corresponds to the mechanism that resembles the hydride mechanism in the type of main intermediates in the catalytic cycle.

CT dose varies with both equipment related and operator dependent factors. Thermoluminescence dosimetry (TLD) was employed in two phantoms to investigate the variation in absorbed dose for head CT scans, using a cylindrical head CT dose phantom. Dose profiles were plotted and the computed tomography dose index (CTDI) calculated for a single 10 mm thick slice on 14 CT scanners. An anthropomorphic head phantom was also scanned from the base-of-skull to the vertex using 10/10 mm slices. The absorbed dose measured at the centre of the scan series is reported (Dmid). The mean CTDIw for the 14 scanners was 60.0 mGy, while the mean Dmid was 45.8 mGy. Dmid better represents the absorbed dose in human tissues. The CTDIw and Dmid normalized to mAs varied by up to a factor of 2.2 for the different scanners. Equipment related factors contribute to such variations. However, variations due to operator dependent factors such as the choice of exposure factors, scanning protocol and positioning technique must also be considered. When such factors are taken into account the absorbed dose received by the patient can vary considerably, by as much as 16.2 for lens dose. Increased awareness of the factors influencing CT dose and the standardization of scanning protocols is recommended.

1.In the phosphorus-containing polydentate ligands, complex formation with the lithium ion occurs mainly via the oxygen atoms of the phosphoryl groups. In the case of the phosphorus-containing macrocycle, the ether oxygen atoms also appear to participate in the coordination.2.On formation of a complex with Eu(fod)3, not only the phosphoryl groups but also the central ether oxygen atom of the phosphorus-containing macrocycle or polydentate ligand participate in the coordination.

1.We have developed a method for the preparation of chloromethylphosphine oxides by substitution of the acetoxy group in acetoxymethylphosphine oxides by chlorine using gaseous HC1 at 180–200°C.2.We have prepared methylbis(chloromethyl)phosphine oxide by reaction of gaseous HC1 with tris(acetoxymethyl)phosphine or tetrakis(hydroxymethyl)phosphonium chloride. In the same way we synthesized dimethylchloromethylphosphine oxide from tris(hydroxymethyl)phosphine methylsulfate.

When heated with glacial acetic acid in the presence of acidic catalysts, acetoxymethylphosphines rearrange to the corresponding methylphosphine oxides.

1.It has been shown by the methods of IR spectroscopy and molecular mechanics that dimethyl (hydroxymethyl) phosphine oxide exists in dilute solutions in CC14, in the form of an equilibrium mixture of conformera.2.An intramolecular hydrogen bond is realized in one of the conformers, and its energy has been estimated from the IR spectra and theoretical data.

It is shown that the interaction between phosphine oxides containing at least two chloromethyl groups (bis(chloromethyl)methylphosphine oxide and tris(chloromethyl)phosphine oxide) with vicinal diols (ethyleneglycol, 1,2-propanediol and pyrocatechol) proceeds simultaneously affording cyclic and acyclic compounds. The seven-membered ring compounds 6-oxo-1,4,6-dioxaphosphepane and 6-oxo-2,3-benzotetrahydro-1,4,6-dioxaphosphepin were isolated. In some of the syntheses the acyclic compounds were isolated also. The structure of the products were elucidated with analytical methods, infrared. 1H and 31P-NMR spectroscopy.

The influence of the ligands Ph2P(CH2)mP(X)Ph2 (L), where m=1, 2 and X=O, S, on the rate and regional selectivity of the hydrocarboxylation of a-olefins has been investigated, catalyzed by PdCl2, in a series of organic solvents. A high regional selectivity of the process (>80%) for products with normal structure has been achieved by using L with m=2, X=O. The influence of the ligand used and of triphenylphosphine on the properties of the catalytic system in the given reaction has been compared.

1.The complexes ArNiXL2 and HNiXL2 (X is halide, L is tertiary phosphine) in the presence of zinc catalyze the condensation of bromobenzene with styrene (stilbene formation).2.The yield of stilbene and 1,3-diphenylbutene, the dimerization product of styrene, in the presence of pyridine is lowered according to the substitution of phenyl groups on the phosphorus ligand L by alkyl (ethyl, cyclohexyl) groups.3.Change of triphenylphosphine to phenylethylphosphines and tricyclohexylphosphine in the hydride complex HNi(X)(PR3)2, the catalytic activity of which falls in the order X=Cl-»Br->I-, favors the dimerization of styrene in the absence of pyridine.

1.Phosphorus-containing monopodands with short polyether chains between the terminal phosphoryl groups are effective complexing agents with respect to the lithium cation.2.Phosphorus-containing mono- and tripodands of high coordination capacity form fairly stable complexes with the whole series of alkali metals, the stability of the complexes in the case of the ligands with flexible glycol fragments being higher than that in the case of the ligands with rigid pyrocatechol fragments.

1.The oxide of the macrocyclic phosphine and its acyclic analog have been synthesized, as well as complexing agents of the monopodand type.2.By using model compounds it has been shown that when the phosphoryl-containing macrocycle complexes with the lithium ion, the phosphoryl group oxygen and, apparently, the central ethereal oxygen, participate in the coordination. For ions of greater radius, the ether oxygens only are involved.3.In the phosphoryl-containing podands, coordination with the lithium ion via the phosphoryl groups is preferred. In complex formation with ions of larger radii, the ether oxygens participate in the coordination.

1.The?P=O absorption band of dimethyl (chloromethyl)-, dimethyl(methoxymethyl)- and dimethyl(phenoxymethyl)phosphine oxides is quite sensitive to complexation with a number of metal salts.2.Complexation constants for these phosphine oxides with copper (II) chloride in acetonitrile have been estimated. The stability constants of the [CuClL]+complexes of I–III are close to one another.

1.Diastereomeric anisochronism was detected in the EPR spectra of phosphoranyl radicals.2.The decay kinetics of phosphoranyl radicals, derivatives of 1,3,2-oxazaphospholanes, were studied.

The oxides of dimethyl(bromomethyl)- and dimethyl(iodomethyl)phosphines exist as equilibrium mixtures of conformer pairs in solution, the form predominating in nonpolar solvents being that in which the phosphoryl and carbon-halogen bonds are in trans orientation.

When acquiring data to characterise radiation beams for radiotherapy treatment planning measurements in steep dose gradients such as beam penumbra or dose build-up are often required. A metal oxide semiconductor field effect transistor (MOSFET) with its inherent high spatial resolution was used for penumbra measurements in a 120 kVp X ray beam. The customised MOSFET system features a pulsed readout that allows the acquisition of data points in user-defined time intervals of less than 1 s. Using a modified scanning beam data acquisition system the penumbra was acquired on-line in 0.1 mm steps. Measurements were made at different distances behind the beam collimator. From the extrapolation of the penumbra width to a location directly under the block the spatial resolution of the MOSFET system can be estimated to be better than 0.1 mm. This excellent spatial resolution has many potential applications in radiotherapy dosimetry, including the characterisation of multileaf collimator systems.