A systematic review comparing the functional changes and complications of DIEP and TRAM flaps in patients receiving breast reconstruction

Aim: Treatment for breast cancer may involve unilateral or bilateral mastectomy, with subsequent breast reconstruction surgery. Using autologous tissue flaps during reconstructive surgery is increasingly popular. The aim of this systematic review was to determine if the DIEP flap is more effective than the TRAM flap for breast reconstruction in females after a mastectomy in terms of donor site morbidity, recipient site morbidity, and functional outcome. Methods: Studies were identified using the databases Medline and Embase and applying predefined search criteria. The limits applied were; peer-reviewed, published between January 1980 to May 2013, human trials, English language. Study inclusion followed a review of the title, abstract, and full text by two independent researchers. Results: Two trends were identified. 1) DIEP flap surgery reduces the risk of abdominal weakness without increasing the risk of flap complications if performed by a surgeon well trained in microsurgery; 2) TRAM flap surgery remains a good alternative due to its evolution towards muscle-sparing techniques. Conclusion: This appears to be the first systematic review in this area of research. The evidence demonstrates that DIEP flap reduces postoperative abdominal morbidity, with no increased flap complication compared to the TRAM flap if performed by a surgeon well trained in microsurgery

Geologic Considerations in Civil Constructions - Malaysian Case Studies

The need for adequate geologic input into civil engineering projects is common knowledge to all. However, quite surprisingly, in many construction projects in Malaysia geologic input is either totally lacking or highly inadequate. An indicator of the extent of neglect of geologic input into civil constructions in Malaysia is the fact that many soil investigation reports for these projects in this country do not contain a section or even a brief write-up on the site geology. This paper presents several case studies of civil engineering projects where geologic factors have been overlooked, thus resulting in the delay in the completion of the project and increase in the final project cost. The examples given include a bridge project, dams, building foundations, piling works and the search for construction materials for the extension of an airport

Some Thoughts on Changing Comparative Advantage

SUMMARY Automation induced by microelectronic technological change will ensure that a few Northern countries which have a lead on the basis of R and D, practical applications and faster diffusion, will have a comparative advantage vis?à?vis the rest of the world for some time to come. This will push the rest of the North—and even more so the South—into a dependency relation. Differences among areas and countries in the speed and direction of diffusion provide a basis for international trade, since it implies differences in absolute and comparative advantage. Given the pattern of output?specialisation, trade will remain strong within the North, within the South and between the two hemispheres. Nevertheless, the overall dependency of the South vis?à?vis the North will increase. RESUME Notes sur l'évolution de l'avantage relatif L'automation émanant de la révolution micro?électronique conférera pour un temps à certains pays du Nord, en avance au plan de la recherche, du développement, des utilisations et de la diffusion, un avantage certain par rapport au reste du monde. Le reste du Nord, et plus encore le Sud, leur seront subordonnés à cet égard. Les différences d'orientation et de rapidité de la diffusion entre régions ou entre pays constituent une base possible pour les échanges internationaux puisqu'elle implique des écarts de position en termes absolus et relatifs. Vu le schéma de la spécialisation de la production, le commerce restera intense au sein du Nord, au sein du Sud et entre les deux hémisphères. Néanmoins, la dépendance du Sud à l'égard du Nord s'accroîtra. RESUMEN Algunas ideas sobre la cambiante ventaja comparativa La automatización inducida por el cambio tecnológico microelectrónico asegurará que algunos países septentrionales que se aventajan sobre la base de la investigación y perfeccionamiento, las aplicaciones prácticas y una divulgación más rápida, tengan una ventaja comparativa en relación con el resto del mundo durante bastante tiempo en el futuro. Esto empujará al resto de los países del norte— e incluso más a los del sur—hacia una relación de dependencia. Las diferencias entre diversas regiones y países en la velocidad y dirección de la divulgación sirven de base para el comercio internacional, ya que implica diferencias de la ventaja absoluta y comparativa. Dadas las modalidades de la especialización en la producción, el comercio seguirá teniendo fuerza dentro de los países septentrionales, dentro de los meridionales y entre los dos hemisferios. No obstante, aumentará la dependencia total del sur en relación con el norte

Protein-DNA charge transport: Redox activation of a DNA repair protein by guanine radical

DNA charge transport (CT) chemistry provides a route to carry out oxidative DNA damage from a distance in a reaction that is sensitive to DNA mismatches and lesions. Here, DNA-mediated CT also leads to oxidation of a DNA-bound base excision repair enzyme, MutY. DNA-bound Ru(III), generated through a flash/quench technique, is found to promote oxidation of the [4Fe-4S](2+) cluster of MutY to [4Fe-4S](3+) and its decomposition product [3Fe-4S](1+). Flash/quench experiments monitored by EPR spectroscopy reveal spectra with g = 2.08, 2.06, and 2.02, characteristic of the oxidized clusters. Transient absorption spectra of poly(dGC) and [Ru(phen)(2)dppz](3+) (dppz = dipyridophenazine), generated in situ, show an absorption characteristic of the guanine radical that is depleted in the presence of MutY with formation instead of a long-lived species with an absorption at 405 nm; we attribute this absorption also to formation of the oxidized [4Fe-4S](3+) and [3Fe4S](1+) clusters. In ruthenium-tethered DNA assemblies, oxidative damage to the 5'-G of a 5'-GG-3' doublet is generated from a distance but this irreversible damage is inhibited by MutY and instead EPR experiments reveal cluster oxidation. With ruthenium-tethered assemblies containing duplex versus single-stranded regions, MutY oxidation is found to be mediated by the DNA duplex, with guanine radical as an intermediate oxidant; guanine radical formation facilitates MutY oxidation. A model is proposed for the redox activation of DNA repair proteins through DNA CT, with guanine radicals, the first product under oxidative stress, in oxidizing the DNA-bound repair proteins, providing the signal to stimulate DNA repair

Evidence for compact cooperatively rearranging regions in a supercooled liquid

We examine structural relaxation in a supercooled glass-forming liquid simulated by NVE molecular dynamics. Time correlations of the total kinetic energy fluctuations are used as a comprehensive measure of the system's approach to the ergodic equilibrium. We find that, under cooling, the total structural relaxation becomes delayed as compared with the decay of the component of the intermediate scattering function corresponding to the main peak of the structure factor. This observation can be explained by collective movements of particles preserving many-body structural correlations within compact 3D cooperatively rearranging regions.Comment: 8 pages, 4 figure

Broadband tuneable travelling wave parametric multiplier based on high-gap superconducting thin film

The well-established technology of the superconducting quantum parametric amplifier (SPA) can be reconfigured to perform functions beyond amplification, such as frequency multiplication, by utilising the low-noise, low-loss superconducting nonlinear transmission line. This versatile technology holds potential for various applications, including ‘pumping’ a millimetre (mm) or sub-mm wave heterodyne mixer or driving a high-frequency SPA. Its significance lies in the ability to incorporate a high-purity signal source into the cryogenic stage alongside the primary detector, thereby eliminating noise associated with room temperature sources. Additionally, there is potential for on-chip integration with the detector circuit, leading to a more compact architecture. This manuscript details the design of a travelling-wave parametric multiplier (TWPaM) that exploits the nonlinear wave-mixing mechanism to enhance the third harmonic growth from a strong pump tone injected into the travelling wave parametric amplifier (TWPA)-like device. While this functionality has been demonstrated previously, it exhibited narrowband performance. In this manuscript, we present our approach to designing a dispersion engineering scheme that enables the generation of broadband tunable tripler tones with high conversion efficiency. We showcase our design methodology using a niobium titanium nitride (NbTiN) high-gap thin-film transmission line as an example. Our presentation includes the theoretical model governing the physics of higher harmonics generation, emphasising phase-matching conditions that allow for broadband operation while suppressing unwanted modes. Although the ultimate aim is to develop a mm/sub-mm TWPaM, we aim to demonstrate the feasibility of their operation with a scaled microwave design in this manuscript. We will show that we can theoretically achieve close to 35% conversion efficiency across approximately 60% operational bandwidth

Breakdown of Hydrodynamic Transport Theory in the Ordered Phase of Helimagnets

It is shown that strong fluctuations preclude a hydrodynamic description of transport phenomena in helimagnets, such as MnSi, at T>0. This breakdown of hydrodynamics is analogous to the one in chiral liquid crystals. Mode-mode coupling effects lead to infinite renormalizations of various transport coefficients, and the actual macroscopic description is nonlocal. At T=0 these effects are weakened due to the fluctuation-dissipation theorem, and the renormalizations remain finite. Observable consequences of these results, as manifested in the neutron scattering cross-section, are discussedComment: 4pp., 1 eps figur

Wave spectra of 2D dusty plasma solids and liquids

Brownian dynamics simulations were carried out to study wave spectra of two-dimensional dusty plasma liquids and solids for a wide range of wavelengths. The existence of a longitudinal dust thermal mode was confirmed in simulations, and a cutoff wavenumber in the transverse mode was measured. Dispersion relations, resulting from simulations, were compared with those from analytical theories, such as the random-phase approximation (RPA), quasi-localized charged approximation (QLCA), and harmonic approximation (HA). An overall good agreement between the QLCA and simulations was found for wide ranges of states and wavelengths after taking into account the direct thermal effect in the QLCA, while for the RPA and HA good agreement with simulations were found in the high and low temperature limits, respectively.Comment: 26 pages, 9 figure