Absence of intersystem crossing in 1,4-didehydrobenzene

The rate of singlet-to-triplet intersystem crossing in 1,4-didehydrobenzene (the biradical produced as a reactive intermediate in the thermal cycloaromatization of enediynes), cannot be increased by the application of an external magnetic field. The rate of product formation and the distribution of stable products of 2,3-di-n-propyl-1,4-didehydrobenzene thermolysis is unchanged at magnetic flux densities in the range 0–2000 G and at 66 000 G. Similarly, the rate of thermolysis of an unsymmetrical enediyne is insensitive to magnetic field flux in the same range. This finding precludes the modulation of enediyne reaction rates in pharmaceutical and synthetic pursuits.

1,1,1-Trichloro-2,2-bis(4-iodophenyl)ethane

In the structure of the title compound C14H9Cl3I2, which is the p-iodophenyl analogue of the insecticide DDT [1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane], isomorphism between the two compounds has been confirmed. In the molecule the dihedral angle between the planes of the two phenyl rings is 65.8(4)deg. which compares with 64.7(7)deg. in DDT.

2,2-Bis(4-butoxyphenyl)-1,1,1-trichloroethane

In the structure of the title compound C22H27Cl302, which is the p-butoxyphenyl analogue of the insecticidally active p-methoxyphenyl compound methoxychlor, the dihedral angle between the two phenyl rings is 79.61(11)deg. Present also in the structure is an intramolecular aromatic C-H...Cl interaction [3.361(2)Ang].

Comments on the Australian Accounting Research Foundation's Legislation Policy Discussion Paper NO.4 (A framework for financial reporting by incorporated associations)

The Australian Accounting Research Foundation (AARF) recently issued Legislative Policy Discussion Paper No.4 which proposes a framework for financial reporting by Australian incorporated associations.This paper comments on both the merits and deficiencies of the proposal. In particular it notes that the proposal simply advocates that the application of differential reporting, accounting standards, and the conceptual framework be imposed on incorporated associations by amended statutes. It is noted that in light of long experience in the corporate sector, he espoused benefits of such a move may not eventuate. Further, concern is expressed that the proposal is a blank cheque one because of the inadequacy of existing relevant accounting standards and the proposal to introduce new relevant standards. Another major defect in the proposal is that it emanates from accountants who acknowledge in their conceptual framework, the need for external reports to report on performance through both financial and non-financial reporting methods. Despite that acknowledgment, the standard set of external reports prepared by accountants do not measure performance as defined in their own conceptual framework (SAC 2) and in their auditing pronouncements (AUP 33), and they have restricted their domain to financial reporting (SAC 2). Accordingly the proposal appears to be seriously deficient and it is suggested that it be rejected and a new proposal be prepared by a multi-party group free from vested interests.

Poly[[diaquabis[mu-2-(4-fluorophenoxy)acetato-k2O1:O1']magnesium] 0.4-hydrate]

In the structure of the title compound, [Mg(H2O)2(C8H6FO3)2]n(0.4H2O)n, slightly distorted octahedral MgO6 complex units have crystallographic inversion symmetry, the coordination polyhedron comprising two trans-related water molecules and four carboxyl O-atom donors, two of which are bridging. Within the two-dimensional complex polymer which is parallel to (100), the coordinating water molecules form intermolecular O---H...O hydrogen-bonds with carboxylate and phenoxy O-atom acceptors, as well as with the partial-occupancy solvent water molecules.

A 3D collision avoidance strategy for UAVs in a non-cooperative environment

This paper presents a feasible 3D collision avoidance approach for fixed-wing unmanned aerial vehicles (UAVs). The proposed strategy aims to achieve the desired relative bearing in the horizontal plane and relative elevation in the vertical plane so that the host aircraft is able to avoid collision with the intruder aircraft in 3D. The host aircraft will follow a desired trajectory in the collision avoidance course and resume the pre-arranged trajectory after collision is avoided. The approaching stopping condition is determined for the host aircraft to trigger an evasion maneuver to avoid collision in terms of measured heading. A switching controller is designed to achieve the spatial collision avoidance strategy. Simulation results demonstrate that the proposed approach can effectively avoid spatial collision, making it suitable for integration into flight control systems of UAVs.

Development of network-level project screening methods supporting the 4-Year pavement management plan in Texas

The Texas Department of Transportation (TxDOT) is concerned about the widening gap between pavement preservation needs and available funding. Thus, the TxDOT Austin District Pavement Engineer (DPE) has investigated methods to strategically allocate available pavement funding to potential projects that improve the overall performance of the District and Texas highway systems. The primary objective of the study presented in this paper is to develop a network-level project screening and ranking method that supports the Austin District 4-year pavement management plan development. The study developed candidate project selection and ranking algorithms that evaluated pavement conditions of each project candidate using data contained in the Pavement Management Information system (PMIS) database and incorporated insights from Austin District pavement experts; and implemented the developed method and supporting algorithm. This process previously required weeks to complete, but now requires about 10 minutes including data preparation and running the analysis algorithm, which enables the Austin DPE to devote more time and resources to conducting field visits, performing project-level evaluation and testing candidate projects. The case study results showed that the proposed method assisted the DPE in evaluating and prioritizing projects and allocating funds to the right projects at the right time.

Identification of bone morphogenetic proteins 2 and 4 in commercial demineralized freeze-dried bone allograft preparations : pilot study

BACKGROUND: Demineralized freeze-dried bone allografts (DFDBAs) have been proposed as a useful adjunct in periodontal therapy to induce periodontal regeneration through the induction of new bone formation. The presence of bone morphogenetic proteins (BMPs) within the demineralized matrix has been proposed as a possible mechanism through which DFDBA may exert its biologic effect. However, in recent years, the predictability of results using DFDBA has been variable and has led to its use being questioned. One reason for the variability in tissue response may be attributed to differences in the processing of DFDBA, which may lead to loss of activity of any bioactive substances within the DFDBA matrix. Therefore, the purpose of this investigation was to determine whether there are detectable levels of bone morphogenetic proteins in commercial DFDBA preparations. METHODS: A single preparation of DFDBA was obtained from three commercial sources. Each preparation was studied in triplicate. Proteins within the DFDBA samples were first extracted with 4M guanidinium HCI for seven days at 40 degrees celsius and the residue was further extracted with 4M guanidinium HCL/EDTA for seven days at 40 degrees celsius. Two anti-human BMP-2 and -4 antibodies were used for the detection of the presence of BMP's in the extracts. RESULTS: Neither BMP-2 nor BMP-4 was detected in any of the extracts. When recombinant human BMP-2 and -4 were added throughout the extraction process of DFDBA extraction, not only were intact proteins detected but smaller molecular weight fragments were also noted in the extract. CONCLUSIONS: These results indicate that all of the DFDBA samples tested had no detectable amounts of BMP-2 and -4. In addition, an unknown substance present in the DFDBA may be responsible for degradation of whatever BMPs might be present.

1,1,1-Trichloro-2,2-bis(4-ethoxyphenyl)ethane

In the title compound, C18H19Cl3O2, which is the 4-ethoxyphenyl analogue of the insecticidally active 4-methoxyphenyl compound methoxychlor, the dihedral angle between the two benzene rings is 60.38(13)deg. An intramolecular aromatic C-H...Cl interaction is present.

Standardising practices improves ambulatory diabetic foot management and reduces amputations : the Queensland Diabetic Foot Innovation Project, 2006 – 2009

Background Diabetic foot complications are recognised as the most common reason for diabetic related hospitalisation and lower extremity amputations. Multi-faceted strategies to reduce diabetic foot hospitalisation and amputation rates have been successful. However, most diabetic foot ulcers are managed in ambulatory settings where data availability is poor and studies limited. The project aimed to develop and evaluate strategies to improve the management of diabetic foot complications in three diverse ambulatory settings and measure the subsequent impact on ospitalisation and amputation. Methods Multifaceted strategies were implemented in 2008, including: multi-disciplinary teams, clinical pathways and training, clinical indicators, telehealth support and surveys. A retrospective audit of consecutive patient records from July 2006 – June 2007 determined baseline clinical indicators (n = 101). A clinical pathway teleform was implemented as a clinical record and clinical indicator analyser in all sites in 2008 (n = 327) and followed up in 2009 (n = 406). Results Prior to the intervention, clinical pathways were not used and multi-disciplinary teams were limited. There was an absolute improvement in treating according to risk of 15% in 2009 and surveillance of the high risk population of 34% and 19% in 2008 and 2009 respectively (p < 0.001). Improvements of 13 – 66% (p < 0.001) were recorded in 2008 for individual clinical activities to a performance > 92% in perfusion, ulcer depth, infection assessment and management, offloading and education. Hospitalisation impacts recorded reductions of up to 64% in amputation rates / 100,000 population (p < 0.001) and 24% average length of stay (p < 0.001) Conclusion These findings support the use of multi-faceted strategies in diverse ambulatory services to standardise practice, improve diabetic foot complications management and positively impact on hospitalisation outcomes. As of October 2010, these strategies had been rolled out to over 25 ambulatory sites, representing 66% of Queensland Health districts, managing 1,820 patients and 13,380 occasions of service, including 543 healed ulcer patients. It is expected that this number will rise dramatically as an incentive payment for the use of the teleform is expanded.

Isopropyl 2,2-bis(4-bromophenyl)-2-hydroxyacetate

In the structure of the title compound C17H16Br2O3, which is a restricted commercial acaricide (common name bromopropylate), has two independent and conformationally similar molecules in the asymmetric unit [dihedral angle between the planes of the two phenyl rings in each, 68.7(4) and 77.4(5)deg]. The C-atoms of the isopropyl group of one of the molecules are disordered over two sites with occupancies of 0.638 and 0.362. Minor non-merohedral twinning was also present in the crystal. Intermolecular hydrogen-bonding interactions involving the hydroxy groups and carboxyl O-atom acceptors give separate centrosymmetric homodimers through cyclic hydrogen-bonding motifs [graph set R2/2(10)].