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Retransplantation candidates are disadvantaged owing to lack of good-quality liver grafts. Strategies that can facilitate transplantation of suboptimal grafts into retransplant candidates require investigation. The aim was to determine whether late liver retransplantation can be performed safely with suboptimal grafts, following normothermic machine perfusion.A prospectively enrolled group of patients who required liver retransplantation received a suboptimal graft preserved via normothermic machine perfusion. This group was compared with both historical and contemporaneous cohorts of patient who received grafts preserved by cold storage. The primary outcome was 6-month graft and patient survival.The normothermic machine perfusion group comprised 26 patients. The historical (cold storage 1) and contemporaneous (cold storage 2) groups comprised 31 and 25 patients respectively. The 6-month graft survival rate did not differ between groups (cold storage 1, 27 of 31, cold storage 2, 22 of 25; normothermic machine perfusion, 22 of 26; P = 0.934). This was despite the normothermic machine perfusion group having significantly more steatotic grafts (8 of 31, 7 of 25, and 14 of 26 respectively; P = 0.006) and grafts previously declined by at least one other transplant centre (5 of 31, 9 of 25, and 21 of 26; P0.001).In liver retransplantation, normothermic machine perfusion can safely expand graft options without compromising short-term outcomes.Liver transplantation is a life-saving procedure for many different diseases. In the UK, one in 10 patients awaiting transplant have had a previous liver transplant. These retransplant operations are complex, and the general belief is that a good-quality donor liver graft is required for best outcomes. However, there is a significant shortage of good-quality organs for liver transplantation, so many patients awaiting retransplantation spend longer on the waiting list. This study investigated whether a new technology, called normothermic machine perfusion, could be used to preserve lower-quality donor livers and have successful outcomes for patients undergoing retransplantation. Traditionally, good-quality livers are preserved in an ice box and the study compared the outcomes of these two different approaches. The aim was to prove that normothermic machine perfusion improves access to transplantation for this group of patients, without compromising outcomes. A group of patients who underwent retransplantation and received a lesser-quality liver preserved with normothermic machine perfusion was compared with two groups of patients who had received a transplant with traditional ice-box preservation. The complications, graft, and patient survival of the former group was compared with those in the latter two groups who underwent liver retransplantation with better-quality liver grafts. The rate of survival and adverse surgical outcomes were comparable between the groups of patients who received a liver preserved via traditional ice-box preservation, and those who received a lesser-quality liver preserved via normothermic machine perfusion. Normothermic machine perfusion can potentially expand the number of suitable donor livers available for retransplant candidates.

At the time of planned pancreatoduodenectomy patients frequently undergo exploratory laparotomy without resection, leading to delayed systemic therapy. This study aimed to develop and validate a prognostic model for the preoperative prediction of resectability of pancreatic head tumours.This was a retrospective study of patients undergoing attempted resection for confirmed malignant tumours of the pancreatic head in a university hospital in Hannover, Germany. The prognostic value of patient and tumour characteristics was investigated in a multivariable logistic regression model. External validation was performed using data from two other centres.Some 109 patients were included in the development cohort, with 51 and 175 patients in the two validation cohorts. Eighty patients (73·4 per cent) in the development cohort underwent resection, and 37 (73 per cent) and 141 (80·6 per cent) in the validation cohorts. The main reasons for performing no resection in the development cohort were: local invasion of vasculature or arterial abutment (15 patients, 52 per cent), and liver (12, 41 per cent), peritoneal (8, 28 per cent) and aortocaval lymph node (6, 21 per cent) metastases. The final model contained the following variables: time to surgery (odds ratio (OR) 0·99, 95 per cent c.i. 0·98 to 0·99), carbohydrate antigen 19-9 concentration (OR 0·99, 0·99 to 0·99), jaundice (OR 4·45, 1·21 to 16·36) and back pain (OR 0·02, 0·00 to 0·22), with an area under the receiver operating characteristic (ROC) curve (AUROC) of 0·918 in the development cohort. AUROC values were 0·813 and 0·761 in the validation cohorts. The positive predictive value of the final model for prediction of resectability was 98·0 per cent in the development cohort, and 91·7 and 94·7 per cent in the two external validation cohorts. [Corrections added on 18 July 2018, after first online publication: The figures for OR of the variables time to surgery and CA19-9 in the abstract and in Table 3 and Table 4 were amended from 1·00 to 0·99].For preoperative prediction of the likelihood of resectability of pancreatic head tumours, this validated model is a valuable addition to CT findings.

Data from 305 non-proprietary compounds tested using the yeast RAD54-GFP (Green Fluorescent Protein) assay, GreenScreen GC, are presented, together with a detailed comparison with results from in vitro and in vivo genotoxicity tests and rodent carcinogenesis. In addition, observations on reproducibility and the performance of the test with autofluorescent and coloured compounds are described. Like the Ames test, the GreenScreen assay is shown to exhibit high specificity (82%), meaning that compounds with positive results are very likely to be genotoxic carcinogens. This is in contrast to mammalian cell tests established for use in regulatory testing that provide disappointingly low specificity and the inevitable generation of confounding false positive data. The analysis confirmed the observations of earlier studies, showing that a combination of an Ames test (or surrogate) with the yeast test provides high specificity as well as high sensitivity in the identification of rodent carcinogens.

An empirical fitting procedure is applied to derive interatomic potential parameters for a model phase transition system, namely potassium tetrachlorozincate (K(2)ZnCl(4)). The derived potential is found to reliably model the known crystallographic structure for the ferroelectric and paraelectric phases of this compound. Potential transferability is demonstrated by applying the parameters derived to the optimization of the known molecular structure for a similar inorganic system (rubidium tetrachlorozincate).

The need to calculate X-ray absorption losses through window materials and electrolytes in electrochemical cells used forin situX-ray studies is highlighted. Calculations of the loss of beam intensity through Mylar windows of various thicknesses and at different wavelengths are carried out. Other window materials, such as polyethylene, polyimide (Kapton), polymethylmethacrylate (Perspex), polycarbonate (Lexan) and polyamide (Kevlar), are considered. Linear absorption coefficients and loss of intensity through different thicknesses of these materials at the CuKα wavelength are considered. Calculations of loss of intensity for a typical experimental case involving a Mylar cell window and a 1.029 MH2SO4electrolyte are presented.

How can a company create and maintain a corporate reputation that effectively addresses key audiences, simultaneously supporting the marketing of its products and services, enhancing the value of company stock and strengthening the sense of corporate culture among its employees? In reality, this is one of the most difficult and complex business challenges facing management today. Moreover, understanding how an organization can best address the challenge begins with an understanding of two key terms: ‘image’ and ‘identity.’

The development of an interatomic potential for alkali perchlorates and phosphates is presented. The potentials are fitted to sodium perchlorate (space group, Cmcm) and calcium phosphate and are transferred to another phase of sodium perchlorate (space group, F 43m) and also the perchlorates of caesium, potassium and rubidium and to the phosphates of strontium and magnesium. The calculated structure and elastic constants are compared with experimental data.

The utility of synchrotron radiation white-beam X-ray topography using real-time imaging as a probe for characterizing the structural nature of solid-solid phase transitions is demonstrated through a study of the paraelectric-to-ferroelectric phase transition in ammonium sulphate at 223 K.

A study of the treatment of a patient who had undergone extensive surgery for carcinoma of the vulva

Background: Tension and bilateral pneumothorax can cause or contribute to death following trauma. A surgical incision (thoracostomy) or needle decompression through the chest wall rapidly treats these conditions. Resuscitation of patients in traumatic cardiac arrest focuses on treating common and reversible life-threatening conditions. A study was undertaken to observe the practice, findings and outcome of chest decompression when performed as part of the resuscitation strategy of these patients by air ambulance crews. Methods: Patients in prehospital traumatic cardiac arrest were identified over a 39-month period from an air ambulance database. The use of thoracostomy or needle decompression was identified together with indications, findings and outcome. Primary outcome was return of cardiac output by arrival at hospital. Results: 18 of 37 cases underwent chest decompression (17 thoracostomy, 1 needle decompression). Four patients had a return of cardiac output (3 tension pneumothorax, 1 bilateral pneumothorax). Six further cases were positive for intrathoracic injury. In 2 cases the injuries identified were incompatible with life and resuscitation efforts were consequently ceased. Conclusions: Chest decompression in traumatic cardiac arrest identifies and treats a high proportion of potentially life-ending injuries and should be considered as part of the resuscitation effort of patients in traumatic cardiac arrest. In a proportion of patients, non-survivable injuries are identified which guide resuscitation efforts.

The numerical method for calculating the elastic constants of molecular crystals, using the crystal packing program PCK 83, developed and applied to the model case of CO2 in previous work is here extended to benzene (C6H6) and urea [(NH2)2CO] crystals. Interatomic potential-energy functions coupled with rigid-molecule constraints are used, taking the entire angular dependence into account. Correlation with other calculations and experimental data is good.

Elastic constants for the study case of CO2 have been obtained in the pair-potential rigid molecule approximation, using the crystal packing programme PCK83. The non-bonded interatomic interactions are described by (exp-6-1) potential energy functions. Strain energy curves and surfaces are fitted with polynomial expressions by a least squares technique. An analysis of the results is presented, yielding values for the constants c11, c12 and c44 that compare well with existing data.

A general theory for the calculation of the elastic constants of molecular crystals has been developed within the pair-potential rigid-molecule approximation. Interatomic rather than intermolecular interactions are considered explicitly, thus taking more angular dependence into account. Model calculations for CO2 have been carried out, the results being in good agreement with those obtained using the crystal packing programme PCK83, with the same set of potentials. Both methods yield lower values than the corresponding intermolecular potential calculations for the c 11, c 12 and c 44 tensor components of CO2.

Extended X-ray absorption fine structure (EXAFS) spectroscopy is applied to an investigation of the structural environment around Zn in polycrystalline K2ZnCi4 over the temperature range associated with its solid-to-solid phase transformations at 127 degrees C and 282 degrees C. The results show a reversible increase in thermal disorder and in the tetrahedral distortion of the ZnCl42- anion upon transformation into the incommensurate phase.

The phosphating of steel in an aqueous zinc-phosphating bath has been studied. Phase formation was controlled poentiostatically and phase identification was performed by X-ray diffraction, using synchrotron radiation, which enabled the time development of phosphate coatings to be studied. Two phases are formed during the phosphating process: hopeite and phosphophyllite, the diffraction patterns of which resemble those obtained from mineral standards. At potentials more negative than 0.6 V vs SCE a pure hopeite phase is formed

A generalised approach for modelling the morphology of molecular crystals in the presence of “tailor-made” additives of both the disrupter and blocker types is presented and demonstrated by a consideration of the effects of a series of additives on the morphology of the long chain normal alkane, docosane (C22H46).

An overview is provided describing the background and use of synchrotron X-radiation techniques for the characterization of crystal growth and related processes. The utility of these techniques is illustrated through a number of case studies.

After the Second World War and in response to concerns as to the expansion of the Eastern Bloc, the European Convention on Human Rights (‘the Convention’) was developed by the Council of Europe. The United Kingdom ratified the Convention in 1951 and by doing so, a number of rights were established for everyone, whether an individual or a company, including the right to liberty, the right to a fair trial and the right to respect for private and family life, home and confidentiality of correspondence.

Structural changes associated with the flash calcination of china clay (Al2 O3 2SiO2H2 O) have been investigated using soft X-ray absorption spectroscopy (XANES and EXAFS) at the Al and Si K edges. The data reveal substantial changes to the atomic environment around the Al atomic sites with a reduction of Al-O bond distances from 1.92Å to 1.81Å associated with a change from 6 to 4 coordination. The changes in the structural environment around Si are found to be more subtle with Si remaining tetrahedrally coordinated.

The energies of dislocations in yttrium aluminium garnet are calculated and the likely configurations of both growth and mechanically induced dislocations in crystals grown from solution and from the melt are discussed.

An assessment is presented of the stability of some organic single crystals on exposure to an intense source of synchrotron radiation during X-ray topography examination. Examples are shown of the variations in defect structure of organic crystals prepared by different growth techniques. This study defines the applicability of a synchrotron radiation source for topographic examination of organic materials.

We have collaborated in the development of the instrumentation for the X-ray topography station at the Daresbury synchrotron radiation source (SRS). This comprises: (a) a white radiation camera for X-ray topography and microscopy 1) ; (b) a double crystal camera for X-ray topography and beam conditioning 1) ; (c) a video imaging system for real time studies 3) ; (d) versatile environmental chambers in situ studies 2) ; and (e) a liquid helium cryostat for deformation and magentics experiments 1,3) . The current status of the programme is reviewed and the instruments are briefly described.

DETERGENTS substances that are promote often defined the reas substances that promote the emoval of dirt. This meaning is the broad, general one given in the dictionary. However, the definition not only applies to household synthetic detergents and industrial detergents, it also encompasses ordinary soap, most surfaceactive agents, many alkaline materials, all solvent cleaners and cleaning fluids, plain water, and even sand and other abrasives. There is a second and

The perfection of single-crystal polymers is of considerable interest in the understanding of the role of defects in the process of solid-state polymerization. Polybis(p-toluene sulphonate) diacetylene (hereinafter referred to as pTS) has been the subject of numerous investigations (see, for example [1]) since it can be obtained as crystals of macroscopic dimensions. This work describes the initial characterization of the bulk perfection of pTS by white radiation topography using a synchrotron source [2]. A previous topographic study has been reported [3]; however, this was mainly confined to surface studies using a conventional source. It has been the aim of this study to assess the stability of pTS in the high photon fluxes of synchrotron radiation with the view to studying in real time the role lattice defects play in the solid-state polymerization process. It is belived to be the first application of synchroton radiation topography (SRT) to polymer single-crystals. pTS crystallizes in the monoclinic space group

During the mid-1920's, when the trend of land settlement in this State began to highlight certain serious shortcomings in the system of administrative mapping employed since 1898, it became apparent that to provide adequate map coverage adaptable to future land development, a more flexible system of cadastral mapping than the old country-parish and other existing systems would have to be introduced.

A simple Fortran computer program XRTDAT is described. This program generates data useful in the planning, execution and interpretation of an X-ray topographic experiment.