bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tris(pentafluorophenyl)boron as an Efficient, Air Stable, and Water Tolerant Lewis Acid Catalyst
Authors: Ishihara Kazuaki , Hanaki Naoyuki , Funahashi Miyuki , Miyata Mayumi , Yamamoto Hisashi 
Published: July 2006

Abstract
Tris(pentafluorophenyl)boron is an efficient, air stable, and water tolerant Lewis acid catalyst for the aldol-type and Michael reactions of silyl enol ethers with carbonyl compounds or other electrophiles (trimethyl orthoformate, dimethyl acetal, and chloromethyl methyl ether), the allylation reaction of allylsilanes with aldehydes, and the Diels–Alder reaction of dienes with α,β-unsaturated aldehydes. A solution of formaldehyde in water is applicable as an electrophile. Also, the aldol-type reaction of ketene silyl acetals with aromatic or aliphatic imines is successfully carried out using the same catalyst.
An Investigation into the Current Peri-Operative Nutritional Management of Oesophageal Carcinoma Patients in Major Carcinoma Centres in England
Authors: Murphy PM , Modi P , Rahamim J , Wheatley T , Lewis SJ 
Published: July 2006

INTRODUCTION Patients with oesophageal carcinoma are at high risk of malnutrition. The aim of this study was to assess current practice for the nutritional management of patients following surgery for oesophageal carcinoma. PATIENTS AND METHODS A postal questionnaire was sent to 82 dietetic departments of those hospitals in England identified as major centres for upper gastrointestinal surgery. RESULTS Of the 66 (80%) responses received, 22 (33%) centres routinely perform pre-operative nutritional screening/assessment on oesophageal carcinoma patients. Centres with dietetic support dedicated to these patients are more likely to perform a pre-operative nutritional assessment (n = 17; 55%) than those without (n = 5; 14%; P < 0.001; χ2 = 12.17). Pre-operative nutritional support is routinely provided in only 11 (17%) centres with the majority of centres (n = 50; 75%), providing it if patients are considered malnourished only. A total of 47 (70%) centres routinely provide postoperative nutritional support with jejunal feeding being the most commonly chosen route. Dedicated dietetic support is provided at 31 (47%) centres. Those centres with a dedicated dietitian are more likely to provide early postoperative nutritional support (n = 27; 87%) than those without (n = 20; 57%; P = 0.007; χ2 = 7.195) and more likely to review patients routinely following discharge from hospital (n = 25 [81%] with a dietitian versus n = 17 [49%] without; P = 0.007; χ2 = 7.2). CONCLUSIONS The nutritional management of patients following surgery for upper gastrointestinal carcinoma is not uniform with practice varying considerably between centres. Those centres with a dedicated dietitian are more likely to assess patients’ nutritional status and provide nutritional support.
Can a Urinary Tract Symptom Score Predict the Development of Postoperative Urinary Retention in Patients Undergoing Lower Limb Arthroplasty Under Spinal Anaesthesia? A Prospective Study
Authors: Sarasin SM , Walton MJ , Singh HP , Clark DI 
Published: July 2006

INTRODUCTION There is no general consensus amongst orthopaedic surgeons on how best to manage the urinary tract and its complications after lower limb arthroplasty. This prospective audit investigates whether postoperative urinary retention can be predicted pre-operatively using the validated International Prostate Symptom Severity score (IPSS). PATIENTS AND METHODS A total of 182 patients undergoing lower limb arthroplasty under spinal anaesthetic were given the IPSS questionnaire to complete pre-operatively and an audit into numbers catheterised postoperatively was performed. RESULTS Overall, 69% of males and 39% of females required catheterisation. Following logistic regression analysis there was 0.85 predicted probability that males over 70 years would require catheterisation. The IPSS score was not useful in predicting retention in either sex at any age. CONCLUSIONS We propose that all males over 70 years undergoing this type of surgery should be catheterised pre-operatively and all other patients should be catheterised postoperatively with close monitoring of bladder volumes to prevent established urinary retention.
Nurse-Led Management of Carpal Tunnel Syndrome: An Audit of Outcomes and Impact on Waiting Times
Authors: Newey Martyn , Clarke Malcolm , Green Tim , Kershaw Christopher , Pathak Pankaj 
Published: July 2006

INTRODUCTION This article describes the outcome of a nurse-led service developed to manage patients referred with a presumptive diagnosis of carpal tunnel syndrome. PATIENTS AND METHODS We developed a rapid-access service in response to unacceptable waiting times for patients with carpal tunnel syndrome. The service was developed around the role of a nurse practitioner providing a single practitioner pathway from first clinic appointment, through surgery to discharge. RESULTS Waiting times improved considerably whilst the standard and quality of care was maintained. CONCLUSIONS There is a role for nurses to perform certain surgical procedures within a well-defined environment.
Quality of Surgical Instruments
Authors: Brophy T , Srodon PD , Briggs C , Barry P , Steatham J , Birch MJ 
Published: July 2006

INTRODUCTION Many surgeons will have encountered the scissors that would not cut, and the artery clip that comes off in a deep difficult location, but it would be reasonable to assume that new instruments should be of assured quality. This study reports the surprising findings of a local quality control exercise for new instruments supplied to a single trust. MATERIALS AND METHODS Between January 2004 and June 2004, all batches of new surgical instruments ordered by the Central Sterile Supplies Department of St Bartholomew's and the Royal London Hospitals were assessed by three clinical engineers, with reference to British Standards (BS) requirements. RESULTS Of 4800 instruments examined, 15% had potential problems. These included 116 with machining burrs and debris in the teeth of the tissue-holding regions, 71 defects of ratcheted instruments, 34 scissors with deficient cutting action, and 35 tissue forceps protruding guide pins. In addition, 254 instruments did not have a visible manufacturer's mark. CONCLUSIONS This study demonstrates the value of local quality control for surgical instruments. This is of importance in an increasingly hazard-conscious environment, where there are concerns over instrument sterilisation, surgical glove puncture and the potential for transmission of blood-borne and prion diseases.
Informing Research in Primary Dental Care: Setting Priorities
Authors: Palmer Nikolaus , Batchelor Paul 
Published: July 2006

This paper suggests that priorities for research in primary dental care should follow the examples set in other areas of primary healthcare. It reviews the history of research in primary dental care, since 1990, and goes on to explain how the Delphi exercise, initiated by the Faculty of General Dental Practice (UK), has identified five priority areas for research in primary dental care. These areas are: 1. Research into the application of evidence-based dentistry into practice. 2. The effects of different systems of remuneration on treatment patterns in practice. 3. The oral health assessment on determining recall intervals and its effect on oral health. 4. Factors that influence and affect dentists’ treatment modalities. 5. The evaluation of the cost benefits of whole team training.
An Audit of the Quality and Content of Periodontal Referrals and the Effect of Implementing Referral Criteria
Authors: Kourkouta Styliani , Darbar Ulpee R 
Published: July 2006

Aims This audit aimed to assess the effect of implementing referral criteria on the quality and content of referral letters sent by general dental practitioners (GDPs) to the periodontal department of a teaching hospital. Methods Retrospective data were collected from a total of 450 referrals made in: (i) 1997, prior to any changes; (ii) 2000/2001, after referral guidelines were implemented; and (iii) 2004/2005, after referral criteria were redefined and circulated via Primary Care Trusts. A standardised data-collection form was used to record the information that was provided in the referral letters. This information was also compared to the findings at initial hospital consultations. Results There was a small improvement in the administrative details provided in the referral communications in 2000/2001 and 2004/2005. Medical history was often incomplete and was mentioned in 31–34% of referral letters. Use of the Basic Periodontal Examination (BPE) score increased from 17% (1997) to 57% (2004/2005). The information on clinical details otherwise increased in 2000/2001 with a tendency to decrease in 2004/2005. There was little agreement between the clinical details in the referral communications and the findings at consultation in the periodontal department. Conclusions Following implementation of referral criteria, there was an increase in the clinical details provided in referral letters. However, the validity of the information provided by the GDPs was often questionable. The number of referrals that provided medical history details remained unchanged. Use of a pro forma was not associated with an improvement in the quality of referrals in this audit.
Entwurfsmethode für den verallgemeinerten virtuellen Aktor zur Rekonfiguration von Regelkreisen (Design Approach to the Generalised Virtual Actuator for Control Reconfiguration)
Authors: Lunze Jan , Richter Jan H. 
Published: July 2006

Abstract
Dieser Beitrag stellt eine neue Methode zur Rekonfiguration linearer Regelungen nach Aktorfehlern vor. Er beschreibt eine Erweiterung des verallgemeinerten virtuellen Aktors zur bestmöglichen statischen Ausnutzung gegebener Redundanzen bei maximaler Nutzung seines schnelleren statischen Anteils. Dazu wird der Begriff der statischen E/A-Rekonfigurierbarkeit unter Verwendung der Markov-Parameter eingeführt. Die Vorgehensweise wird anhand eines Beispiels gezeigt.
Fritz H. Laves – 100 years young
Authors: Parthé Erwin 
Published: July 2006

Abstract
This year Fritz Laves, professor for crystallography and petrography and head of the Mineralogical Department at the University and the Eidgenössische Technische Hochschule in Zurich from 1954 to 1976, an accomplished leading scientist and outstanding pioneer in crystal chemistry, would be 100 years old.
Fritz H. Laves – an ideal for generations
Authors: Fischer Werner 
Published: July 2006

Abstract
Fritz Laves' 100th birthday is an excellent reason to recollect his merits for the German and the international crystallography in general. This, however, would be a task too difficult for me though I consider myself a scientific grandson of him. Laves' crystallographic oeuvre (cf. Hellner, 1980) is almost too comprehensive to be valued by a single person of my generation. Accordingly, I will confine myself mainly on our common field of interest, i.e. on Mathematical Crystallography.
Gustav E. R. Schulze's pioneering work on Laves phases
Authors: Paufler Peter 
Published: July 2006

Abstract
There are several reasons to recollect the merits of Gustav Ernst Robert Schulze on the occasion of Fritz Laves' anniversary. Firstly, he had been a good friend of Laves and shared his interest in intermetallic compounds. Secondly, his work on Laves phases, though containing important early results, is less well known for some reasons. Thirdly, Schulze was the founder of a very efficient research centre on intermetallics in Dresden which is still active today. Finally, he introduced Metal Physics at the TU Dresden as a broad subject of bringing together structure and properties of the metallic state from a more fundamental point of view. Later on, this had a clustering effect for the development of materials research institutes in Dresden.
Atomic ordering in the Laves phases L1 V(Co1–xSix)2 (x = 0.43 and 0.56)
Authors: Conrad Matthias , Pohling Christoph , Webert Holger , Harbrecht Bernd 
Published: July 2006

Abstract
The synthesis, phase relations, and crystal structures of two truly ternary, partially ordered Laves phases occurring in the V—Co—Si system are reported. The phases termed L1 V(Co1–xSix)2 are found in two distinct phase fields next to TiMnSi-type VCoSi. This so-called E-phase emerges in the centre of the miscibility gap which separates the Co- and Si-rich Laves phase fields. Both fields accommodate several structurally distinct L-phases. The L1-phases V(Co1–xSix)2 (x = 0.43 and 0.56) crystallise in √3a × √3a superstructures of the hexagonal MgZn2 structure type. A rigorous symmetry-based analysis reveals that, at the given compositions, this type of superstructure affords sufficient structural degrees of freedom for ordering of Co and Si atoms on 4 different sites in a manner that enables tuning of hetero-atomic Co—Si interactions to an optimum.
Microscopic structures of Laves phases and structurally related compounds: a transmission electron microscopy study
Authors: Yokosawa Tadahiro , Söderberg Karin , Boström Magnus , Grüner Daniel , Kreiner Guido , Terasaki Osamu 
Published: July 2006

Abstract
We present microstructural investigations of Laves phases AB2 and structurally related compounds using transmission electron microscopy. Convergent-beam electron diffration in combination with selected-area diffraction has been used to determine uniquely the space group symmetry of the respective phases from very small illuminated regions. In addition stacking faults, domain boundaries, and intergrowth have been studied by HREM images. By electron beam irradiation intermetallic phases have been transformed in-situ into phases of different compositions. Polar intermetallic phases in the systems Ca—Al—Zn, Ba—Al and Ba—Al—Zn, as well as transition metal based Nb-Co phases have been chosen for this case study. In the Ca—Al—Zn system, the C15- and C36-type crystals did not show orderliness but a randomly mixed occupation of the B-net by Al and Zn atoms. Starting from C36, a C15 phase of constant Ca and lower Zn content as well as a new C36 phase with higher Ca content could be synthesized by means of electron beam irradiation. In the case of CaAlZn no ordering of Al and Zn were observed, i.e., Al and Zn randomly mixed occupy the Cu-site in the CeCu2 structure type. By electron beam irradiation of CaAlZn, a novel hexagonal phase with a hitherto unknown crystal structure is formed. The crystal structures of Ba21Al40 and Ba14Al22+xZn5–x are derived from Laves-type structures by omitting and modifying some of the triangular and Kagom, layers. In the case of Ba21Al40, intergrowth of motifs from the crystal structures of Ba3Al5 and Ba4Al5 were observed, whereas for Ba14Al22+xZn5–x the bulk phase displays a domain structure. Adjacent domains are misoriented by ∼120°, the specific angle resulting from the pseudo-trigonal symmetry of the Ba-net. Therefore, only the (Al,Zn)-net is disordered. No superstructure formation were detected for the three polytypes C36, C15 and C14 in the Nb—Co system. However, TEM images of C36-Nb1–xCo2+x reveal a high stacking fault density with intergrowth of stacks of C36 and C15 sequence. When the C15 phase is rich in Nb, stacking faults seem to be more important than for Co-rich C15 phases, whereas stacking faults have seldom been observed for the Co-rich C14 phase.
Crystal growth and magnetic properties of rare earth borosilicides
Authors: Mori Takao 
Published: July 2006

Abstract
B12 icosahedra cluster-containing rare earth borosilicides REB44Si2 (RE = Tb, Dy, Ho, Er, Tm, Yb) were grown by the floating zone method and their physical properties were investigated. REB44Si2 compounds are isostructural to REB50 and they are unique among the newly discovered boron-rich phases in that it is possible to grow large crystals with dimensions exceeding 10 mm. The rare earth atoms form a coupled chain structure like a ladder along the c-axis which is also the axis along which there is a B12 icosahedral chain. Magnetic properties, resistivity, and specific heat of the compounds were investigated. The conductivity follows the 3D variable range hopping mechanism and it was determined that localization lengths ξ are extremely short, actually close to the distances of the atoms themselves. Magnetic transitions above 4 K are indicated for all the compounds except for TmB44Si2 and it is found that specific heat measurement is the expedient probe of such compounds in which the low temperature susceptibility is influenced by external conditions such as crystal growth rate. Despite dimer-like features to the magnetic transition a spin gap is not observed. The magnetic coupling in these systems is indicated to be different from the conventional mechanisms in f-electron systems of dipole-dipole coupling or RKKY interaction.
Structure refinements of iron borides Fe2B and FeB
Authors: Kapfenberger Christine , Albert Barbara , Pöttgen Rainer , Huppertz Hubert 
Published: July 2006

Abstract
Crystals of the iron borides FeB and Fe2B were obtained from two different high temperature synthesis routes, viz. in combined copper/gallium flux and under high pressure conditions. Their crystal structures were investigated at room and low temperatures. Structure models from the literature were confirmed. The position of the boron atoms was unambiguously determined. FeB (Pnma, no. 62) contains zig-zag chains of boron atoms in which the boron atoms are coordinated by seven iron atoms in the form of a mono-capped trigonal prism. Fe2B (I4/mcm, no. 140) contains single boron atoms in a square antiprismatic iron atom coordination.
Filling the CoSn host-cell: the HfFe6Ge6-type and the related structures
Authors: Venturini Gerard 
Published: July 2006

Abstract
The crystallographic properties of the CoSn-based MT6X6 compounds (M = alkaline-, alkaline earth-, transition metals, lanthanides and actinides, T = transition metal, X = element of the main group) are reported. The filling scheme and the features of the diffraction patterns are detailed and illustrated by the new LuFe6Ge6–xGax series. The members of the hexagonal, orthorhombic and monoclinic series are presented. The crystal chemistry and the structural evolutions as a function of the size of the components and of the valence electron concentration are reported.
Synthesis and characterization of Na2Ba4Ga2Sb6 and Li13Ba8GaSb12
Authors: Todorov Iliya , Sevov Slavi C. 
Published: July 2006

Abstract
The title compounds were synthesized from the elements by heating the corresponding stoichiometric mixtures at high temperature. Their structures were determined from single-crystal X-ray diffraction. Na2Ba4Ga2Sb6 (Pnma, Z = 8, a = 12.3468(10) Å, b = 10.6621(10) Å, c = 13.8344(10) Å) contains chains of ∞[Ga2Sb6]10–. The repeating unit is made of an edge-sharing Ga-centered tetrahedron GaSb2(μ-Sb)2 and another Ga-centered tetrahedron but with additional antimony that is exo-bonded to one of the corners forming Sb–Sb dumbells, i.e. GaSb(Sb–Sb)(μ-Sb)2. The unit connects to neighboring units via sharing two corners of the tetrahedra, i.e. [Ga2Sb5Sb2/2]. Li13Ba8GaSb12 (C2/m, Z = 2, a = 18.0650(10) Å, b = 4.9407(10) Å, c = 13.0123(10) Å, β = 126.728(10)°) contains three different types of anions: single-atom anions of Sb3–, dumbells of Sb4–, and isolated Ga-centered tetrahedra of GaSb4
9–. The two compounds are electronically balanced, and this is confirmed by four-probe conductivity and magnetic measurements. Their very narrow band gaps, 0.014 and 0.049 eV for Na2Ba4Ga2Sb6 and Li13Ba8GaSb12, respectively, make them potential thermoelectric materials.
A novel series of sphere packings with arbitrarily low density
Authors: Dorozinski Tadeusz E. , Fischer Werner 
Published: July 2006

Abstract
The search for a least dense packing of spheres makes sense only under suitable restrictions because otherwise sphere packings of arbitrarily low density may be constructed. As has been shown before, the condition that all spheres have to be equal as well in their size as in their number of contacts is not such an effective restriction. A sharper condition is the demand that all spheres must have congruent patterns of contacts, i.e. that they must coincide in their first neighbourhood. The example presented here proves that also this restriction is not sufficient to avoid sphere packings with densities approaching zero.
On the limits of toxicant-induced tolerance testing: Cotolerance and response variation of antibiotic effects
Authors: Schmitt Heike , Martinali Bennie , Van Beelen Patrick , Seinen Willem 
Published: July 2006

AbstractPollution-induced community tolerance (PICT) as an ecotoxicological test system has been claimed to detect pollutant effects highly specifically and sensitively. However, the specificity might be limited by the occurrence of cotolerance. Another limitation of the application of any ecotoxicological test system lies in variation of the measured responses. We tested the variation and the occurrence of cotolerance experimentally, using antibiotics as toxicants, soil microcosms as microbial communities, and tolerance determination in Biolog plates as PICT detection test. Bacteria have been discussed as being prone to multiple tolerances due to the possible accumulation of multiple resistance genes on mobile genetic elements. However, in our experiments, cotolerance occurred only between antibiotics of the same group (oxytetracycline and tetracycline), as expected from their identical mode of action. Cotolerance between oxytetracycline and tylosin in soil microcosms exposed to oxytetracycline was low, as was cotolerance to oxytetracycline in tylosin-exposed microcosms. We conclude that tolerance development to antibiotics in soils reflects the actual selection pressure rather than a general pattern of multiple resistances. Concerning variation, the PICT effect of tetracycline was well reproducible in two consecutive years. The response variation linked to PICT experiments in controlled microcosms was comparable to that of ecotoxicological test systems of equivalent complexity. In conclusion, our results support an application of the PICT methodology as an effective means to study the soil ecotoxicology of antibiotics.
Field evaluation of an avian risk assessment model
Authors: Vyas Nimish B. , Spann James W. , Hulse Craig S. , Borges Shannon L. , Bennett Richard S. , Torrez Martin , Williams Bruce I. , Leffel Robert 
Published: July 2006

AbstractWe conducted two laboratory subacute dietary toxicity tests and one outdoor subacute dietary toxicity test to determine the effectiveness of the U.S. Environmental Protection Agency's deterministic risk assessment model for evaluating the potential of adverse effects to birds in the field. We tested technical-grade diazinon and its D·Z·N® 50W (50% diazinon active ingredient wettable powder) formulation on Canada goose (Branta canadensis) goslings. Brain acetylcholinesterase activity was measured, and the feathers and skin, feet, and gastrointestinal contents were analyzed for diazinon residues. The dose–response curves showed that diazinon was significantly more toxic to goslings in the outdoor test than in the laboratory tests. The deterministic risk assessment method identified the potential for risk to birds in general, but the factors associated with extrapolating from the laboratory to the field, and from the laboratory test species to other species, resulted in the underestimation of risk to the goslings. The present study indicates that laboratory-based risk quotients should be interpreted with caution.