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Procedures involving the small saphenous vein (SSV) can result in sural nerve (SN) damage due to the proximity of the two structures. The relationship between the SN and SSV has previously been described in cadaveric studies with limited scope on surface landmarks. This study investigates the relationship between the SN and SSV in vivo through ultrasound. Transverse/short-axis ultrasound scans of 128 legs (64 healthy participants) were taken by a single observer using a GE Logiq e ultrasound system with a 5-13 Hz linear transducer (GE Logiq 12L-RS). The SN was identified and traced from the lateral malleolus to the popliteal fossa noting its course and proximity to the SSV. The distance between the SN and SSV was measured at points representing the distal 50% and 25% of the total leg length (the distance between the medial tibial condyle and the inferior edge of the medial malleolus). The SN and SSV were visualized in all participants regardless of BMI and atypical anatomical relationship were noted in 20.3%. The SN pierced the fascia in the distal 25.9% ± 5.3% of the total leg length. The distance between the SN and SSV was 4.06 ± 1.8 mm and 3.4 ± 1.4 mm in the distal 50% and 25% points of the total leg length, respectively. There was no significant effect of sex or body side. The SSV is a viable option for multiple vein harvest. Ultrasound visualization can be a beneficial tool for delineating variations of the SN in relation to SSV prior to surgery. Clin. Anat. 32:277-281, 2019. © 2018 Wiley Periodicals, Inc.

The incident of post-pancreaticojejunostomy anastomotic stricture has been reported about 5%1) . Endoscopic trans-anastomotic drainage using balloon-assisted enteroscopy (BAE) is the initial management option for this adverse event in most cases. However, the success rate of this procedure is relatively low2) . Hence, EUS-guided pancreatic duct drainage (EUS-PD) has emerged as an alternative method.

Objectives To analyze long-term outcomes of robot-assisted partial nephrectomy for treatment of complex cystic renal tumors. Methods We retrospectively analyzed the data of patients who underwent robot-assisted partial nephrectomy for cystic (n = 32) and solid (n = 263) renal masses at Severance Hospital, Seoul, Korea. The primary outcome was assessment of perioperative safety for cystic tumor. Secondary outcomes were evaluation of long-term oncological and functional results. Results Patients' clinical and demographic characteristics were similar among both groups. The median follow up of cystic and solid masses were 58 and 46 months, respectively. Cystic masses were more likely to have low Fuhrman grade 1 and 2 (P = 0.03), and shorter operative time (P = 0.04) compared with solid masses. There was no statistically significant difference regarding warm ischemia time, estimated blood loss, trifecta achievement, length of hospital stay, complication rates and renal function preservation (P > 0.05) between groups. In the solid group, 12 patients (4.1%) recurred, and six patients (2%) died from metastatic renal cell carcinoma, whereas the patients in the cystic group did not have any local or distance recurrence, and the survival rates were 100%. The 5-year cancer-free survival (P = 0.77), cancer-specific survival (P = 0.65) and overall survival (P = 0.83) rates were similar between the groups. Conclusion Robot-assisted partial nephrectomy appears to be safe and feasible treatment for complex cystic renal masses. It confers excellent long-term oncological outcomes. Robot-assisted partial nephrectomy should be the treatment of choice for complex cysts whenever feasible.

To compare perioperative trifecta achievement and long-term oncological and functional outcomes between patients with renal tumours of low [Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) score 6-7], intermediate (PADUA score 8-9) and high (PADUA score ≥10) complexity undergoing robot-assisted partial nephrectomy (RAPN), and to determine predictors for trifecta achievement.Data were retrospectively analysed from 295 patients, who underwent RAPN, between 2006 and 2015, at a high-volume tertiary centre. Trifecta achievement was the primary outcome measurement. The perioperative parameters and long-term oncological and functional outcomes were the secondary outcome measures. Groups were compared using the Kruskal-Wallis H test or chi-square test. Univariable and multivariable binary logistic regression analyses were used to determine the most important determinant variables associated with trifecta accomplishment. The Kaplan-Meier method was used to estimate overall survival (OS), cancer-specific survival (CSS) and cancer-free survival (CFS).Of the 295 patients, 121 (41%) had a PADUA score of ≥10. Patients in the high-complexity PADUA group had larger tumours (P ≤ 0.001), higher clinical stages ≥T1b (P0.001), an increased risk of malignancy (P = 0.02), longer warm ischaemia time (P = 0.0030), and higher estimated blood loss (P = 0.001) compared with those in the intermediate- and low-complexity groups. Seven of eight patients who were converted to radical nephrectomy had high-complexity tumours (P = 0.02). Trifecta achievement was less in the high-complexity PADUA group (P0.001). Renal functional outcomes did not differ among the groups at follow-up (P0.05). There were no significant differences between the groups for OS (P = 0.314), CSS (P = 0.228) and CFS (P = 0.532). In multivariable analysis, the American Society of Anesthesiologists classification, operative time and tumour size were independent predictors of trifecta achievement (P = 0.001, P = 0.03, and P = 0.006, respectively).High-complexity PADUA tumours are associated with a lower rate of trifecta achievement; however, long-term oncological and functional outcomes seem to be equivalent among high-, intermediate-, and low-complexity tumours. Despite the perioperative outcomes; high-complexity tumours can be handled successfully via the robotic approach and the improved long-term oncological and functional outcomes might be considered useful for patients counselling.

Heart disease is one of the leading causes of death in the world. There is a growing demand for in vitro cardiac models that can recapitulate the complex physiology of the cardiac tissue. These cardiac models can provide a platform to better understand the underlying mechanisms of cardiac development and disease and aid in developing novel treatment alternatives and platforms towards personalized medicine. In this review, a summary of engineered cardiac platforms is presented. Basic design considerations for replicating the heart’s microenvironment are discussed considering the anatomy of the heart. This is followed by a detailed summary of the currently available biomaterial platforms for modeling the heart tissue in vitro. These in vitro models include 2D surface modified structures, 3D molded structures, porous scaffolds, electrospun scaffolds, bioprinted structures, and heart-on-a-chip devices. The challenges faced by current models and the future directions of in vitro cardiac models are also discussed. Engineered in vitro tissue models utilizing patients’ own cells could potentially revolutionize the way we develop treatment and diagnostic alternatives.

Background The epidemiology of and risk factors for invasive mold disease (IMD) among allogeneic hematopoietic cell transplant (HCT) recipients may vary according to the region. In this study, we sought to evaluate risk factors for IMD in our patient population. Methods Between May 2007 and July 2009, all HCT recipients from 8 Brazilian centers were followed prospectively until 1 year post transplant. Cases of IMD were classified as early (before day +40) or late (after day +40). Patients with IMD (cases) were compared with controls (patients without IMD) using univariate and multivariate Cox regression analysis. Results Among 345 HCT recipients, 28 IMDs were diagnosed. Risk factors for early IMD were acute myeloid leukemia (hazard ratio [HR] 2.95, 95% confidence interval [95% CI] 1.13–7.68, P = 0.03) and transplant with a human leukocyte antigen-mismatched donor (HR 3.38, 95% CI 1.18–9.68, P = 0.02), and for late IMD risk factors were lymphoma (HR 8.49, 95% CI 2.35–30.68, P = 0.001), cytomegalovirus reactivation (HR 5.51, 95% CI 1.15–26.47, P = 0.03), and neutropenia (HR 3.49, 95% CI 1.01–12.13, P = 0.049). Conclusion The variables identified in this study may help to define risk groups, and to tailor special preventive measures to patients at higher risk to develop IMD.

Objectives To determine the incidence, risk factors and causes of hospital readmission in a large series of patients who underwent radical cystectomy (RC) and urinary diversion. Patients and Methods We retrospectively analysed the data of 1000 patients who underwent RC and urinary diversion between January 2004 and September 2009 in our tertiary referral centre. Patients stayed in hospital for 21 and 11 days for orthotopic and ileal conduit diversions, respectively. The primary outcome was the development of a complication requiring hospital readmission at ≤3 months (early) and >3 months (late). Causes of hospital readmissions were categorised according to frequency of readmissions. Predictors were determined using univariate and multivariate logistic regression models. Results In all, 895 patients were analysed excluding 105 patients because of perioperative mortality and loss to follow-up. Early and late readmissions occurred in 8.6% and 11% patients, respectively. The commonest causes of first readmission were upper urinary tract obstruction (UUO, 13%) and pyelonephritis (12.4%) followed by intestinal obstruction (11.9%) and metabolic acidosis (11.3%). The development of postoperative high-grade complications (odds ratio [OR] 1.955; 95% confidence interval [CI] 1.254–3.046; P = 0.003) and orthotopic bladder substitution (OR 1.585; 95% CI 1.095–2.295; P = 0.015) were independent predictors for overall hospital readmission after RC. Postoperative high-grade complications (OR 2.488; 95% CI 1.391–4.450; P = 0.002), orthotopic bladder substitution (OR 2.492; 95% CI 1.423–4.364; P = 0.001) and prolonged hospital stay (OR 1.964; 95% CI:1.166–3.308; P = 0.011) were independent predictors for early readmission while hypertension (OR 1.670; 95% CI 1.007–2.769; P = 0.047) was an independent predictor for late readmission. Conclusion Hospital readmissions are a significant problem after RC. In the present study, UUO, pyelonephritis, metabolic acidosis and intestinal obstruction were the main causes of readmission. Orthotopic bladder substitution and development of postoperative high-grade complications were significant predictors for overall readmission.

In traditional communication systems the transmission medium is considered as a given characteristic of the channel, which does not depend on the properties of the transmitter and the receiver. Recent experimental demonstrations of the feasibility of extending the laser cavity over the whole communication link connecting the two parties, forming an ultra-long fiber laser (UFL), have raised groundbreaking possibilities in communication and particularly in secure communications. Here, a 500 km long secure key distribution link based on Raman gain UFL is demonstrated. An error-free distribution of a random key with an average rate of 100 bps between the users is demonstrated and the key is shown to be unrecoverable to an eavesdropper employing either time or frequency domain passive attacks. In traditional communication systems the transmission medium is considered as a given characteristic of the channel, which does not depend on the properties of the transmitter and the receiver. Recent demonstrations of the feasibility of extending the laser cavity over the whole communication link connecting the two parties, forming an ultra-long fiber laser (UFL), have raised groundbreaking possibilities in communication. Here, a 500 km long secure key distribution link based on Raman gain UFL is demonstrated. © 2014 by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Polymorphs of molecular crystals are often very close in energy, yet they may possess very different physical and chemical properties. The understanding of polymorphism is therefore of great importance for a variety of applications, ranging from drug design to nonlinear optics and hydrogen storage. While the crystal structure prediction blind tests conducted by the Cambridge Crystallographic Data Centre have shown steady progress toward reliable structure prediction for molecular crystals, several challenges remain, including molecular salts, hydrates, and flexible molecules with several stable conformers. The ability to identify and rank all of the relevant polymorphs of a given molecular crystal hinges on an accurate description of their relative energetic stability. Hence, a first-principles quantum mechanical method that can attain the required accuracy of around 0.1–0.2 kcalmol 1 would clearly be an indispensable tool for polymorph prediction. In this work, we show that accounting for the nonadditive many-body dispersion (MBD) energy beyond the standard pairwise approximation is crucial for the correct qualitative and quantitative description of polymorphism in molecular crystals. We demonstrate this through three fundamental and stringent benchmark examples: glycine, oxalic acid, and tetrolic acid. These systems represent a broad class of molecular crystals, comprising hydrogenbonded (H-bonded) networks of amino acids and carboxylic acids. Among the first-principles methods, density functional theory (DFT) is the most widely used approach in the study of polymorphism in molecular crystals. However, most common exchange-correlation functionals (including hybrid functionals) are based on semi-local electron correlation, and thereby fail to capture the contribution of dispersion interactions to the stability of molecular crystals. These ubiquitous noncovalent interactions are quantum mechanical in nature and correspond to the multipole moments induced in response to instantaneous fluctuations in the electron density. To incorporate these long-range electron correlation effects within DFT, significant progress has been made by using the standard C6/R 6 pairwise additive expression for the dispersion energy. Indeed, DFT with pairwise dispersion terms can yield accurate results when the energy differences between molecular crystal polymorphs are sufficiently large. Notably, Neumann et al. have achieved the highest success rate in the last two blind tests using such methods. However, these pairwise dispersion approaches, even when used in conjunction with state-of-the-art functionals, are still unable to reach the level of accuracy required to describe polymorphism in many relevant molecular crystals, including glycine and oxalic acid. Recently, a novel and efficient method for describing the many-body dispersion (MBD) energy has been developed, building upon the Tkatchenko–Scheffler (TS) pairwise method. Within the TS approach, the effective dispersion coefficients (C6) are calculated from the DFTelectron density, hence the effect of the local environment of an atom in a molecule is accurately accounted for by construction. The MBD method presents a two-fold improvement over the TS approach by including: 1) the long-range electrodynamic screening through the self-consistent solution of the dipole– dipole electric-field coupling equations for the effective polarizability, and 2) the non-pairwise-additive many-body dispersion energy to infinite order through diagonalization of the Hamiltonian corresponding to a system of coupled fluctuating dipoles. The inclusion of the MBD energy in DFT leads to a significant improvement in the binding energies between organic molecules, and for the cohesion of the benzene and oligoacene molecular crystals. The MBD energy, like the TS energy, can be added to any DFT functional, requiring only the adjustment of a single rangeseparation parameter per functional. [*] N. Marom, J. R. Chelikowsky Center for Computational Materials Institute for Computational Engineering and Sciences The University of Texas at Austin Austin, TX 78712 (USA) E-mail: noa@ices.utexas.edu

This study shows the development of new polymeric open-cell foams from polypropylene (PP) and polylactide (PLA) resins with a focus on sound absorption properties and modeling of these foams. The objective is to develop new environmentally friendly foams to replace the existing non-recyclable Polyurethane foams are currently used for sound insulation in industry. Through this research, open-cell foams of about 90% porosity were fabricated from PP and PLA. These resins were selected since PP is a recyclable thermoplastic polymer, and PLA is a bio-based thermoplastic polymer made from renewable resources. Polyurethane (PU) foam which is currently used for sound absorption and noise control in industry was compared to the fabricated PP and PLA foams. As the first attempt to fabricate environmentally friendly acoustic foams, the resulting foam structures show improved properties as compared to the existing materials. The average absorption of PP and PLA foams fabricated is in the range of 0.42–0.55 which is comparable or even higher than the average absorption of PU foam. To better understand the effect of structural and material properties on sound absorption and further improve the acoustic performance of bio-based foams, an analytical model based on Johnson–Champoux–Allard model was used to numerically simulate the acoustic performance of foams under study. POLYM. ENG. SCI., 2013. © 2013 Society of Plastics Engineers

The increased prevalence of obstructive sleep apnea (OSA) in congestive heart failure (CHF) may be associated with rostral fluid shift. We investigated the effect of overnight rostral fluid shift on pharyngeal collapsibility (Pcrit), pharyngeal caliber (APmean), and apnea‐hypopnea index (AHI) in CHF patients. Twenty‐three optimally treated systolic CHF patients were studied. Neck circumference was measured immediately prior to sleep in the evening and immediately after waking in the morning as a marker of rostral fluid shift. Pcrit was measured during sleep, early and late in the night. APmean was measured using acoustic reflection at the same times as neck circumference measurements. 15/23 CHF patients experienced an overnight increase in neck circumference; overall neck circumference significantly increased overnight (mean±SD, evening: 41.7 ± 3.2 cm; morning: 42.3 ± 3.1 cm; P = 0.03). Pcrit increased significantly overnight (early‐night: −3.8 ± 3.3 cmH 2 O; late‐night: −2.6 ± 3.0 cmH 2 O; P = 0.03) and APmean decreased (evening: 4.2 ± 1.3 cm 2 ; morning: 3.7 ± 1.3 cm 2 ; P = 0.006). The total AHI correlated with neck circumference ( r = 0.4; P = 0.04) and Pcrit ( r = 0.5; P = 0.01). APmean correlated with neck circumference ( r = −0.47; P = 0.02). There was no significant change in AHI between the first and second half of the night (first‐half: 12.9 ± 12.4/h; second‐half: 13.7 ± 13.3/h; P = 0.6). Overnight rostral fluid shift was associated with increased pharyngeal collapsibility and decreased pharyngeal caliber during sleep in CHF patients. Rostral fluid shift may be an important mechanism of OSA in this patient group.

The definitive version can be found at: http://onlinelibrary.wiley.com/ Copyright Royal College of Obstetricians and Gynaecologists [Full text of this article is not available in the UHRA]

Foams with open-cell structures have improved sound absorption abilities over conventional closed-cell foams. One technique to optimize the acoustic abilities of open-cell foams is to control their cellular properties through the manipulation of processing parameters. This article presents a novel process to synthesize open-cell polymeric foams for acoustic applications. The process combined rotational foam molding and particulate leaching to produce foams with open-cell networks that are desirable for acoustic absorption. Open-cell foams with open-porosity of about 0.90 were successfully fabricated with this combined foaming process. Effects of processing parameters on the cellular and acoustic properties of the foam samples were examined and discussed. On the basis of the results from the study, the cellular and acoustic properties of the foam fabricated from the proposed method can be controlled through the use of different salt particle sizes in the process. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers

High internal phase emulsion (HIPE) polymerization foaming process is controlled for the production of novel foams with various microcellular structures and morphologies. In this study, two types of organoclay and one type of natural clay, sodium montmorillonite (NaMMT) were introduced at different concentrations to control the microcellular morphologies, cell sizes and open cell contents. A scanning electron microscopy was used to observe the microcellular morphologies and open cell contents; volume expansion ratio (VER) and cell sizes were evaluated. It was believed that the open cell contents increased as organoclay content increased, due to the lowering of the viscosity ratio of dispersed to continuous phases, as a result of adding nanoclay into the oil phase of emulsion. A correlation between the open cell content and VER that depended on clay content was attempted and the result was quite satisfactory. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd.