Vertical rectus abdominis myocutaneous versus alternative flaps for perineal repair after abdominoperineal excision of the rectum in the era of laparoscopic surgery

Aims: Plastic surgical reconstruction of the perineum is often required after abdominoperineal excision of the rectum. Options for this reconstruction include a vertical rectus abdominis myocutaneous (VRAM) flap, gluteal fasciocutaneous flap, and gracilis myocutaneous flap. Although the VRAM flap is well established at most centers, less experience exists with the gluteal and gracilis flaps. In the era of laparoscopic colorectal resection, plastic surgeons are being forced to use gluteal and gracilis flaps because the VRAM flap must be tunnelled intra-abdominally requiring laparotomy. We therefore aimed to systematically review the evidence comparing VRAM, gluteal, and gracilis flaps. Methods: A comprehensive, structured literature search was conducted using Medline, Google Scholar, and Science Direct. Studies included were randomized control trials and observational studies documenting complication rates associated with the VRAM, gluteal, or gracilis flap. Results: Eleven studies meeting all inclusion and exclusion criteria were identified. When meta-analyzed, the overall rate of any perineal wound or flap complication among VRAM patients (35.8%) was significantly lower than gluteal flap (43.7%) and gracilis flap patients (52.9%) (P = 0.041). Conclusions: The VRAM flap is well established for perineal reconstruction, and this study suggests that it may be superior to the gluteal and gracilis flaps in terms perineal wound and flap complication rates. This should be taken into account when weighing up the risks and benefits of a laparoscopic approach to abdominoperineal excision of the rectum. Large studies making direct comparisons between the flap options should be conducted

Assessment of shoulder active range of motion in prone versus supine:A reliability and concurrent validity study

Background: As swimming and surfing are prone dominant sports, it would be more sport specific to assess shoulder active range of motion in this position. Objectives: To determine the reliability of the inclinometer and HALO© for assessing shoulder active range of motion in supine and prone and the concurrent validity of the HALO©. Concurrent validity is based on the comparison of the HALO© and inclinometer. To determine if active range of motion (AROM) differences exists between prone and supine when assessing shoulder internal (IR) and external rotation (ER). Design: The design included clinical measurement, reliability and validity. Methods: Thirty shoulders (mean age = 26.8 years) without pathology were evaluated. Measurements were taken in supine and prone with both an inclinometer and HALO© device. Results: Active ER ROM in prone was significantly higher than in supine when using both devices. Intra-rater reliability (within and between session) intraclass correlation coefficient (ICC) values ranged between 0.82–0.99 for both devices in supine and prone. An ICC test revealed a significant (p \u3c 0.01) correlation for both devices in IR and ER movements (ICC3,1 = 0.87 and ICC3,1 = 0.72), respectively. Conclusion: This study has shown prone assessment of active ER and IR ROM to be a reliable and appropriate method for prone dominant athletes (swimmers and surfers). In this study greater ER ROM was achieved in prone compared to supine. This finding highlights the importance of standardizing the test position for initial and follow up assessments. Furthermore the HALO© and inclinometer have been shown to be reliable tools that show good concurrent validity

Analysing the SML97 Definition: Lexicalisation

The specification of the syntax and semantics for Standard ML have been designed to support the generation of a compiler front end, but actual implementations have required significant modification to the specification. Since the specification was written there have been major advances in the development of language analysis systems that can handle general syntax specifications. We are revisiting the SML specification to consider to what extent, using modern tooling, it can be implemented exactly as originally written. In this short paper we focus on the lexical specification

Orthomodular-Valued Models for Quantum Set Theory

In 1981, Takeuti introduced quantum set theory by constructing a model of set theory based on quantum logic represented by the lattice of closed linear subspaces of a Hilbert space in a manner analogous to Boolean-valued models of set theory, and showed that appropriate counterparts of the axioms of Zermelo-Fraenkel set theory with the axiom of choice (ZFC) hold in the model. In this paper, we aim at unifying Takeuti's model with Boolean-valued models by constructing models based on general complete orthomodular lattices, and generalizing the transfer principle in Boolean-valued models, which asserts that every theorem in ZFC set theory holds in the models, to a general form holding in every orthomodular-valued model. One of the central problems in this program is the well-known arbitrariness in choosing a binary operation for implication. To clarify what properties are required to obtain the generalized transfer principle, we introduce a class of binary operations extending the implication on Boolean logic, called generalized implications, including even non-polynomially definable operations. We study the properties of those operations in detail and show that all of them admit the generalized transfer principle. Moreover, we determine all the polynomially definable operations for which the generalized transfer principle holds. This result allows us to abandon the Sasaki arrow originally assumed for Takeuti's model and leads to a much more flexible approach to quantum set theory.Comment: 25 pages, v2: to appear in Rev. Symb. Logic, v3: corrected typo

Recognition is not parsing — SPPF-style parsing from cubic recognisers

AbstractIn their recogniser forms, the Earley and RIGLR algorithms for testing whether a string can be derived from a grammar are worst-case cubic on general context free grammars (CFG). Earley gave an outline of a method for turning his recognisers into parsers, but it turns out that this method is incorrect. Tomita’s GLR parser returns a shared packed parse forest (SPPF) representation of all derivations of a given string from a given CFG but is worst-case unbounded polynomial order. The parser version of the RIGLR algorithm constructs Tomita-style SPPFs and thus is also worst-case unbounded polynomial order. We have given a modified worst-case cubic GLR algorithm, that, for any string and any CFG, returns a binarised SPPF representation of all possible derivations of a given string. In this paper we apply similar techniques to develop worst-case cubic Earley and RIGLR parsing algorithms