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Efficacy of cleaning methods against SARS-CoV-2 suspended in either 5% soil load (SARS-soil) or simulated saliva (SARS-SS) was evaluated immediately (hydrated virus, T0) or 2 hours post-contamination (dried virus, T2). Hard water dampened wiping (DW) of surfaces, resulted in 1.77–3.91 log reduction (T0) or 0.93–2.41 log reduction (T2). Incorporating surface pre-wetting by spraying with a detergent solution (D + DW) or hard water (W + DW) just prior to dampened wiping did not unilaterally increase efficacy against infectious SARS-CoV-2, however, the effect was nuanced with respect to surface, viral matrix, and time. Cleaning efficacy on porous surfaces (seat fabric, SF) was low. W + DW on stainless steel (SS) was as effective as D + DW for all conditions except SARS-soil at T2 on SS. DW was the only method that consistently resulted in > 3-log reduction of hydrated (T0) SARS-CoV-2 on SS and ABS plastic. These results suggest that wiping with a hard water dampened wipe can reduce infectious virus on hard non-porous surfaces. Pre-wetting surfaces with surfactants did not significantly increase efficacy for the conditions tested. Surface material, presence or absence of pre-wetting, and time post-contamination affect efficacy of cleaning methods.

The expansion of robotic surgery requires identifying factors of competent robotic bedside assisting. Surgical trainees desire more robotic console time, and we hypothesized that protocolized robotic surgery bedside training could equip Advanced Practice Providers (APPs) to meet this growing need. No standardized precedent exists for training APPs.We designed a pilot study consisting of didactic and clinical skills. APPs completed didactic tests followed by proctored clinical skills checklists intraoperatively. Operating surgeons scored trainees with 10-point Likert scale (5 not confident,5 = confident). APPs scoring5 advanced to a solo practicum. Competence was defined as: didactic test score75Of 10 APP trainees, 5 passed on initial attempt. After individualized development plans, 4 passed retesting. Differences in trainee factors were not statistically significant, but the probability of passing the practicum was50% if more than four checklists were needed.Clinical experience, not didactic knowledge, determines the probability of intraoperative competence. Increasing clinical proctoring did not result in higher probability of competence. Early identification of APPs needing individualized improvement increases the proportion of competent APPs.

The management of ventral incisional hernias (VIH) has undergone many iterations over the last 5 years due to evolution in surgical techniques and advancement in robotic surgery. Four general principles have emerged: mesh usage, retromuscular mesh placement, primary fascial closure, and usage of minimally invasive techniques when possible. The application of robotic retromuscular repairs in VIH allow these principles to be applied simultaneously. This qualitative review attempts to answer what robotic retromuscular repairs are described, which patients are selected for these techniques, and what are current outcomes. Using the key words: “robotic retromuscular repair”, “robotic Rives Stoppa”, and “robotic transversus abdominis release”, a PubMed search of articles written up to December 2019 was critically reviewed. 44 articles were encountered, 9 high-quality articles were analyzed for this manuscript. Level of evidence ranged from 2B to 2C. Robotic TAR patients had BMI of 33 kg/m2, defect sizes ranging from 7–14 cm wide to 12–19 cm long, longer OR times, no difference in surgical site events, and shorter length of stay (LOS). The techniques to perform robotic Rives Stoppa (RS) were heterogeneous; however, extended totally extraperitoneal (ETEP) approach is most described. Defect width for RS repairs ranged 4–7 cm and LOS was less than 1 day. Complication rates were low, there is no long-term data on hernia recurrence, and information on cost is limited. In short-term follow-up, robotic retromuscular repairs show promise that VIH can be repaired with intramuscular mesh, few complications, and shorter LOS. Data on hernia recurrence, long-term complications, and rigorous cost analysis are needed to demonstrate generalizability.

Capturing twin nucleation in crystal plasticity is a long-standing problem due to its localisation and site sensitivity. Quantifying local energy to induce a stable twin is a unique challenge and p...

We experimentally and numerically examined the localization behavior of { 10 1 ¯ 2 } extension twins in strongly and weakly textured AZ31 and ZEK100 magnesium alloys as they depart from the surface toward the center of the sheet under the mechanical action of three-point bending. Strain measurement analysis using digital image correlation revealed that twin banding occurs only in the sharply textured AZ31, but with a characteristic spacing between the bands which decreases with the twin height and applied strain. ZEK100 did not exhibit any ordered localization of bands and behaved as a “true” polycrystal. This finding is in agreement with micromechanical calculations by the present authors . We show that full-field plasticity finite element crystal plasticity model was unable to capture many important 2D features of the twin banding. This suggest that twin shear transfer, non-local effects, and the third dimension effects should be included into this model.

A heat treatment methodology is described for obtaining ultra-high strength (> 1700 MPa) and increased − 40 °C toughness (> 45 J/cm2) in a steel. Thermodynamic approach to design heat treatments is demonstrated and utilized to produce refinement of the prior austenite grain size leading to superior properties. The cleavage energy was shown to correlate to both prior austenite grain size, according to an inverse root relationship, as well as the density of high-angle martensite lath boundaries.

The X-ray computed tomography (XCT) technique is a widely applicable and powerful non-destructive inspection modality for evaluation and analysis of geometrical and physical characteristics of materials, especially internal structures and features. XCT is applicable to metals, ceramics, plastics, and polymer and mixed composites, as well as components and materiel. The Army Research Laboratory (ARL) and its partners are currently investigating the use of cast iron-manganese-aluminum (FeMnAl) steel alloy material in support of weight reduction initiatives in Army Development Programs. Steel alloy FeMnAl has been identified as a key enabling material technology to reduce the weight in ground combat vehicle systems. A set of FeMnAl blocks each approximately 50.8 mm (2 in.) thick by 76.2 mm (3 in.) wide by 76.2 mm (3 in.) long, which had been sectioned from an industrially cast ingot (∼12,000 lbs.), were individually scanned by XCT using a conventional 450 kV X-ray source and a solid-state flat panel detector. Mainly due to the thickness of the blocks, as well as a desire to keep geometric unsharpness relatively small which affected overall scan geometry (set up), the scans had a very low response at the detector through the FeMnAl blocks. With the calibrated detector response through air (i.e., around a block) at 85–90% the response through the block was only 5–10%. The XCT scanning parameters and overall protocol used to mitigate the very low-intensity throughput and achieve acceptable scan image results will be discussed. Image processing (IP) methods used to segment porosity features in the FeMnAl blocks will also be discussed.

Alloy partitioning during heat treatment in a lightweight precipitation hardened steel was investigated using transmission electron microscopy and atom probe tomography. The mechanical properties are discussed as a function of the effect of solution treatment temperature and aging time, giving rise to variations in chemical modulation. A wrought lightweight steel alloy with a nominal composition of Fe-30Mn-9Al-1Si-1C-0.5Mo (wt. %) was solution-treated between 1173–1273 K and aged at 773 K. Lower solution treatment temperatures retained a finer grain size and accelerated age hardening response that also produced an improved work hardening behavior with a tensile strength of −1460 MPa at 0.4 true strain. Atom probe tomography indicated these conditions also had reduced modulation in the Si and Al content due to the reduced aging time preventing silicon from diffusing out of the κ-carbide into the austenite. This work provides the framework for heat-treating lightweight, age hardenable steels with high strength and improved energy absorption.

Hot compression testing was performed on specimens of an Fe–30Mn–9Al–1Si-0.9C-0.5Mo wt.% low density steel which were extracted from an industrial casting with large grain size (320 ± 50 μm). Grain boundaries act as nucleation sites for dynamic recrystallization in the present material and the large grain size results in fewer nucleation sites, which delays dynamic recrystallization to larger strains and/or higher temperatures and causes higher rates of work hardening relative to similar materials but with smaller grain sizes. A relatively high activation energy for hot deformation of 470 ± 90 kJ mol−1 was determined from a Zener-Hollomon analysis of the flow stresses at different temperatures and strain rates, attributed in part to the large grain size.

Continued research on advanced high strength steels is an important step in reducing weight and fuel consumption of modern vehicles. Fe–Mn–Al–C steels that have increased concentrations of both Al and Mn, are currently under development to achieve these goals. Alloys with sufficiently high Al and C contents are precipitation hardenable, strengthening the steel by forming nano-sized κ-carbide precipitates, (Fe,Mn)3AlC. In this study, the toughness and phase stability of a Fe–Mn–Al–C steel was investigated by examining evolution of the γ-austenite matrix and κ-carbide precipitates using scanning electron microscopy (SEM), transmission election microscopy (TEM), and synchrotron radiation x-ray diffraction (SR-XRD). Impact toughness was examined using hardness and Charpy impact testing, and results are compared with CALPHAD predictions. This study illuminates proposed mechanisms for simultaneously improving strength and toughness in age-hardenable Fe–Mn–Al–C steels by examining the effect of various heat treatments on the γ-austenite matrix and κ-carbide precipitates.

The effect of dilute alloying additions on the cathodic reaction thermodynamics occurring on the magnesium basal (0001) surface was studied using a first principles approach. The stability of alloying additions on the Mg(0001) surface was considered as a function of surface energy and shown to be a function of implicit solvation. The work function of the alloyed surfaces was also largely affected by the use of an implicit solvent, with alloyed surfaces becoming increasingly noble and the pure magnesium surface becoming less noble after solvation. The cathodic reaction was considered as a three part sequence: (1) water dissociation, (2) hydrogen diffusion, and (3) hydrogen evolution. The water dissociation reaction became endothermic for Ge, In, Sb, and Sn dilute alloying, whereas Ca, Sc, Y, Ti, and Zr enhanced the already favorable water dissociation reaction. Two mechanisms of preventing hydrogen evolution were considered, with early period elements (Ca, Sc, Ti, Y, and Zr) preventing hydrogen evolution f...

Ionic liquids have many advantages over traditional aqueous electrosynthesis for fabrication of functional nanoarchitectures, including enabling the integration of nanoparticles into traditional coatings, superhydrophobicity, nanofoams, and other hierarchical structures. Shape and size control through ionic liquid selection and processing conditions can synthesize nanoparticles and nanoarchitectures without the use of capping agents, surfactants, or templates that are often deleterious to the functionality of the resultant system. Here we give a brief overview of some recent and interesting applications of ionic liquids to the synthesis of nanoparticles and nanoarchitectures.

Background Chemotherapy is associated with postoperative ventral incisional hernia (PVIH) after right hemicolectomy (RHC) for colon cancer, and abdominal wall closure technique may affect PVIH. We sought to identify clinical predictors of PVIH. Methods We retrospectively analyzed patients who underwent RHC for colon cancer from 2008-2018 and later developed PVIH. Time to PVIH was analyzed with Kaplan-Meier analysis, clinical predictors were identified with multivariable Cox proportional hazards modeling, and the probability of PVIH given chemotherapy and the suture technique was estimated with Bayesian analysis. Results We identified 399 patients (209 no adjuvant chemotherapy and 190 adjuvant chemotherapy), with an overall PVIH rate of 38%. The 5-year PVIH rate was 55% for adjuvant chemotherapy, compared with 38% for none (log-rank P < .05). Adjuvant chemotherapy (hazard ratio [HR] 1.65, 95% confidence interval [CI] 1.18-2.31, P < .01), age (HR .99, 95% CI .97-1.00, P < .01), body mass index (HR 1.02, 95% CI 1.00-1.04, P < .01), and neoadjuvant chemotherapy (HR 1.92, 95% CI 1.21-3.00, P < .01) were independently associated with PVIH. Postoperative ventral incisional hernia was more common overall in patients who received adjuvant chemotherapy (46% compared with 30%, P < .01). In patients who received adjuvant chemotherapy, the probability of PVIH for incision closure with #1 running looped polydioxanone was 42%, compared with 59% for incision closure with #0 single interrupted polyglactin 910. Discussion Exposure to chemotherapy increases the probability of PVIH after RHC, and non–short stitch incision closure further increases this probability, more so than age or body mass index. The suture technique deserves further study as a modifiable factor in this high-risk population.

Background: Open ventral incisional hernia repairs with mesh reduce hernia recurrence rates to less than 10%. The Rives-Stoppa retrorectus hernia repair technique is becoming the standard of care for mesh repair of complex incisional hernias. In these hernia repairs, mesh has traditionally been fixated with transfascial sutures, but fibrin glue has been used as an alternative to reduce pain and may also reduce operative time and the risk of seroma formation. The primary objective of this study was to compare the rates of hernia recurrence and seroma formation in cancer patients who underwent Rives-Stoppa incisional hernia repair using transfascial sutures vs. fibrin glue for mesh fixation. Methods: We conducted a retrospective review of a prospectively maintained database of cancer patients at our free-standing cancer institution who underwent Rives-Stoppa ventral incisional hernia repair performed at our institution. Fisher’s exact test was used to assess differences in hernia recurrence and seroma formation rates between patients who underwent mesh fixation with transfascial sutures vs. fibrin glue. Using a neutral prior probability distribution, a Bayesian analysis was performed to evaluate the posterior probability of seroma formation requiring intervention and hernia recurrence after retrorectus repair with fibrin glue fixation. Log-rank test was used to assess the difference in overall survival between the two groups. Results: Forty-one patients (22 in the transfascial suture group and 19 in the fibrin glue group) were included in the analysis. The patient demographics were similar in both groups. There was no statistically significant difference in seroma formation requiring drainage by interventional radiology (IR) between the fibrin glue and the transfascial suture groups (5.3% vs. 9.1%; P=1.00). The odds of having a hernia recurrence was 4 times higher in the transfascial suture group than in the fibrin glue fixation group, but this was not statistically significant (18.2% vs 5.3%, p=0.35). The Bayesian analysis showed a 90% probability that the hernia recurrence rate would be higher in the transfascial suture than in the fibrin glue fixation group. Conclusion: Using fibrin glue instead of transfascial sutures may reduce hernia recurrences and seroma formation in cancer patients undergoing ventral incisional hernia repairs with retro rectus mesh. The high probability of reducing the odds of hernia recurrence with fibrin glue fixation warrants a prospective randomized, multi-institutional clinical trial.

A low density, high strength medium-Mn steel was processed to produce a bimodal duplex microstructure consisting of coarse grained γ-austenite with fine δ-ferrite grains decorating the γ-austenite boundaries. Using a combination of ex situ analysis and in situ neutron diffraction, the deformation mechanisms and lattice strains within each phase were identified for specimens undergoing uniaxial tension during room and elevated temperature loading up to 473 K. The coarse-grained high stacking fault energy γ-austenite deformed by dislocation glide, providing work hardening and ductility. Simultaneously, the fine grained δ-ferrite produced an elevated yield strength by strengthening the steel via a composite reinforcing mechanism. Neutron diffraction reveals that the yield strength reduction at elevated temperatures is due to a reduction in the δ-ferrite strength. The resulting combination 1200 MPa ultimate strength and 0.3 ductility achieved in this microstructurally engineered bimodal duplex steel exceeds that of typical hot worked medium-Mn steels.

Energy Coupled to Matter concepts such as magnetic field-assisted processing were used to align rare earth-doped alumina ceramics in the presence of applied fields. The addition of gadolinium and ytterbium dopants to alumina increased the magnetic susceptibility anisotropies, and induced magnetic torques that led to significant alignment of ceramic particles under the application of magnetic fields as low as 1.8 Tesla. In comparsion, undoped alumina materials showed minimal alignment under applied field strengths as high as 9 Tesla. Density function theory modeling indicated that the specific dopant typed dictated changes in the magnetic properties of different rare earth-doped alumina systems by directly affecting the magnetic moment localization and magnetocrystalline anisotropy.

Density functional theory was used to study the effect of rare-earth dopants on the structure, phase stability, and magnetic properties of α- and θ-Al2O3. Lanthanide series rare-earth dopants (Pr, Nd, Gd, Er, and Yb) were considered at a doping concentration of 0.83 at.%. Incorporation of rare-earth dopants was found to increase the lattice parameters and exaggerate the local structural distortion around the dopant. The extent of local lattice distortion was correlated with the dopant ionic radii. The phase stability of rare-earth-doped Al2O3 was assessed by comparing cohesive and defect formation energies for doped and undoped α- and θ-Al2O3. Rare-earth dopants increased the relative stability of the metastable θ-Al2O3, although doped α-Al2O3 remained more stable. The total magnetic moment of the doped Al2O3 was shown to correlate with the number of unpaired electrons. The magnetic moment was also found to be strongly localized on the rare-earth dopant for Er, Gd, Nd, and Pr-doped Al2O3. In contrast, the Yb dopant induced a delocalized magnetic moment on ~80% of the oxygen atoms. These results further the understanding of dopant incorporation mechanisms, as well as the doping effect on phase stability and magnetic properties that may be applied to advanced field-assisted material synthesis and processing for enhanced properties.

This study evaluates the role of thermomechanical processing and heat treatment on the microstructure and mechanical properties of a hot rolled, annealed, and aged Fe-18Mn-10Al-0.9C-5Ni (wt%) steel. The steel exhibited rapid age hardening kinetics when aged in the temperature range of 500&ndash, 600 &deg, C for up to 50 h, which has been shown in other work to be the result of B2 ordering in the ferrite and &kappa, carbide precipitation within the austenite matrix. The ultimate tensile strength increased from 1120 MPa in the annealed condition to 1230 MPa after 2 h of aging at 570 &deg, C. Charpy V-notch toughness was evaluated at &minus, 40 &deg, C in sub-sized specimens with a maximum in the annealed and quenched condition of 28.5 J in the L-T orientation.

The mechanical behavior of twinning- and transformation-induced plasticity steels, commonly referred to as TWIP and TRIP steels, are characterized by linear hardening followed by an abrupt decrease in the hardening rate. We develop an empirical model that captures salient features of the strain hardening behavior. The model emphasizes ease of implementation into computer codes and identifying parameters from macroscopic data over physically motivated parameters; however, parameters fit to the mechanical response of several alloys show a direct correlation between some parameters and stacking fault energy. Finite element simulations of TWIP and TRIP steels under uniaxial tension show the lack of post-necking elongation observed experimentally is directly related to how abruptly the hardening decreases after the linear hardening regime. A scheme is then proposed for computing some hardening parameters directly from composition so that the model is compositionally-sensitive. This method is demonstrated on medium to high Mn steels so that the mechanical behavior can be predicted using the stacking fault energy, which is computed as a function of composition.

BackgroundEarly cholecystectomy (EC) for acute cholecystitis (AC) is standard. Often patients with cancer are not EC candidates and require non-surgical treatments. We analyzed factors associated with non-surgical treatments and progression to interval cholecystectomy (IC).Materials and methodsWe performed a case–control study reviewing consults for AC from 2001 to 2017 in a tertiary cancer center. Study patients had cancer, abdominal pain, and positive imaging studies. Univariate analysis and regression modeling evaluated associations between non-surgical management, resolution of AC, and IC.Results206 patients met the criteria. 20 underwent EC, 132 took antibiotics (ABX), and were treated with 54 percutaneous cholecystostomy tubes (PCTs). AC resolution was higher with PCT versus ABX (94% vs. 80%, p=0.02). Univariate analysis revealed higher absolute neutrophil counts (ANCs) and longer length of stay in PCT, and logistic regression revealed independent associations of abdominal malignancy (OR=6.66, 95% CI 1.36 to 32.6, p=0.09), abdominal radiation (OR=0.09, 95% CI 0.02 to 0.53, pConclusionPCT has a higher success rate of resolving AC than ABX. Abdominal malignancy increases odds of resolution; abdominal radiation decreases odds. Nausea/vomiting and recent chemotherapy, coupled with rising ANC are associated with IC, but less than 50% of patients return for operation. PCT may not be a bridge to IC in our population.Level of evidence II.

The need for new weight-saving high-strength materials has been increasing in recent years. The demand for fuel efficiency in the auto industry has driven research in the development of lightweight materials and structures while maintaining crash worthiness and safety. The constraints on vehicle weight is also felt in the defense industry. The need to maintain or reduce weight while enhancing protection and durability is a critical goal for the DoD. Fe-Mn-Al is a family of alloys which have been identified as a potential replacement for high strength structural steel such as RHA. Fe-Mn-Al has shown similar properties and performance with 10–15% reduction in weight when compared to RHA (Howell, Microstructural Influence on Dynamic Properties of Age Hardenable FeMnAl Alloys, 2009).

To evaluate recurrence and survival for patients with occult (T0N+) breast cancer who underwent contemporary treatment, assessing outcomes for breast conservation and mastectomy. We performed a single-institution review of women with occult breast cancer presenting with axillary metastasis without identifiable breast tumor or distant metastasis. We excluded patients with tumors in the axillary tail or mastectomy specimen, patients with additional nonbreast cancer diagnoses, and patients with a history of breast cancer. Breast conservation was defined as axillary node dissection with radiation therapy, without breast surgery. We evaluated patient, tumor, treatment, and outcome variables. Patients were assessed for local, regional, and distant recurrences. Overall survival was calculated using the Kaplan–Meier method. Thirty-six patients met criteria for occult breast cancer. Most of these patients (77.8 %) had N1 disease. Fifty percent of cancers (n = 18) were estrogen receptor–positive; 12 (33.3 %) were triple-negative. All patients were evaluated with mammography. Thirty-five patients had breast ultrasound (97.2 %) and 33 (91.7 %) had an MRI. Thirty-four patients (94.4 %) were treated with chemotherapy and 33 (91.7 %) with radiotherapy. Twenty-seven patients (75.0 %) were treated with breast conservation. The median follow-up was 64 months. There were no local or regional failures. One distant recurrence occurred >5 years after diagnosis, resulting in a 5-years overall survival rate of 100 %. There were no significant survival differences between patients receiving breast conservation versus mastectomy (p = 0.7). Breast conservation—performed with contemporary imaging and multimodality treatment—provides excellent local control and survival for women with T0N+ breast cancer and can be safely offered instead of mastectomy.

The effect of 3d and 4d transition metal (TM) additions on the intrinsic stacking fault energy (SFE) in fcc Fe is studied to elucidate the role of alloying in the deformation mechanisms in austenitic steels. The results of ab initio calculations reveal that only Mn reduces the SFE, stabilizing the local hcp structure, whereas all other d-additions are expected to decrease the hcp → fcc transformation temperature and restrain the e-martensite formation. We predict a parabolic dependence of SFE on the atomic number of d-element across the series, with the largest increase in SFE obtained for the early and late elements in the d-series that follow the difference in the valence electrons between the TM and Fe atoms. To understand the SFE behavior in fcc Fe alloys, the driving forces for the fcc to hcp phase transformations of transition metal X and solid solution Fe–X were considered with an ab initio approach. It is found that the solution model explains the SFE trends for all TM additions except the late TMs with fully occupied d-shells (Cu and Ag).

We present a multi-proxy mineral record based on X-ray diffraction and diffuse reflectance spectrophotometry analysis for two cores from the western Indus Shelf in order to reconstruct changing weathering intensities, sediment transport, and provenance variations since 13 ka. Core Indus-10 is located northwest of the Indus Canyon and exhibits fluctuations in smectite/(illite + chlorite) ratios that correlate with monsoon intensity. Higher smectite/(illite + chlorite) and lower illite crystallinity, normally associated with stronger weathering, peaked during the Early–Mid Holocene, the period of maximum summer monsoon. Hematite/goethite and magnetic susceptibility do not show clear co-variation, although they both increase at Indus-10 after 10 ka, as the monsoon weakened. At Indus-23, located on a clinoform just west of the canyon, hematite/goethite increased during a period of monsoon strengthening from 10 to 8 ka, consistent with increased seasonality and/or reworking of sediment deposited prior to or during the glacial maximum. After 2 ka terrigenous sediment accumulation rates in both cores increased together with redness and hematite/goethite, which we attribute to widespread cultivation of the floodplain triggering reworking, especially after 200 years ago. Over Holocene timescales sediment composition and mineralogy in two localities on the high-energy shelf were controlled by varying degrees of reworking, as well as climatically modulated chemical weathering.

We present results from the first high-resolution seismic reflection survey of the inner Western Indus Shelf, and Indus Delta, Arabian Sea. The results show major regional differences in sedimentation across the shelf from east to west, as well as north to south, both since the Last Glacial Maximum (~20 ka) and over longer time scales. We identify 10 major regional reflectors, interpreted as representing sea level lowstands. Strong compressive folding is observed underlying a reflector we have called Horizon 6 in the north-western shelf, probably compression associated with the transpressional deformation of the Murray Ridge plate boundary. Downslope profiles show a series of well developed clinoforms, principally at the shelf edge, indicating significant preservation of large packages of sediment during lowstands. These clinoforms have developed close to zones of deformation, suggesting that subsidence is a factor in controlling sedimentation and consequently erosion of the Indus Shelf. These clinoforms fan out from dome features (tectonic anticlines) mostly located close to the modern shoreline.

Ion implantation was used to modify the surface chemistry of magnesium in order to improve the corrosion resistance. Metalloids which have recently been shown to reduce the cathodic reaction kinetics in magnesium alloys, were implanted into high purity polycrystalline magnesium at varying doses and the composition gradient, microstructure, and electrochemical behavior were characterized. The primary chemical reactions at a magnesium alloy surface during corrosion are water reduction, wherein water is split to evolve hydrogen, and oxidation of Mg to Mg2+. Recently, germanium and arsenic have been reported to have a significant impact on the kinetics of the cathodic water reduction reaction by inhibiting the recombination of hydrogen atoms and subsequent evolution of H2 gas from the Mg surface.(1, 2) Density functional theory (DFT) has provided support for these observations indicating unfavorable enthalpy changes for adsorbed hydrogen atom diffusion toward several metals and metalloids alloyed on a magnesium surface.(3) The DFT results also showed that the reaction enthalpy of diatomic hydrogen evolution was unfavorable on a dilute Mg-metalloid surface. Ion implantation into the surface of metals has been known to improve wear and corrosion resistance, alter conductivity and optical properties, and improve thermal oxidation resistance. For example, the corrosion resistance of 1070 and 52100 steels has been improved by implanting Ta or Ti. Although lesser studied than some substrates, implantation into Mg and Mg alloys has been examined for corrosion and wear in implantable medical devices.(4-6) Implantation of Y into Mg and of Al into AZ31 is known to increase open circuit potential (OCP) and co-implantation of Cr and O is known to form a protective oxide film. This study examines the role of ion implantation in forming protective, corrosion resistant magnesium surface alloys. Germanium and arsenic ions were implanted at 1532 keV into high-purity Mg samples using a National Electrostatics 5SDH-2 positive ion accelerator at doses sufficient to achieve 1-micrometer thick doped layers with peak concentrations of 0.01-0.3 atomic percent at approximately 1.5 micrometers beneath the surface. The depth of implantation and concentration were verified using Rutherford backscattering spectrometry, and were consistent with what had been expected from the ion implantation simulation program SRIM. Energy dispersive spectroscopy, and x-ray photoelectron spectroscopy were used to characterize surface chemistry. Surface morphology was characterized using scanning electron microscopy, tunneling electron microscopy, and atomic force microscopy. Higher concentrations of Ge and As were both observed to roughen the alloy surface, generating a thick MgO surface film, whereas low doses had a minimal effect. The corrosion behavior was evaluated using potentiodynamic polarization and immersion in quiescent NaCl. In order to de-convolute the effect of surface oxide thickness from the chemical effect of the alloying addition, Mg was also implanted into the Mg substrate as a reference. 1. R. Liu, M. Hurley, A. Kvryan, G. Williams, J. Scully and N. Birbilis, Scientific Reports, 6(2016). 2. N. Birbilis, G. Williams, K. Gusieva, A. Samaniego, M. A. Gibson and H. N. McMurray, Electrochemistry Communications, 34, 295 (2013). 3. K. R. Limmer, K. S. Williams, J. P. Labukas and J. W. Andzelm, CORROSION, 73, 506 (2017). 4. C. Liu, Y. Xin, X. Tian, J. Zhao and P. K. Chu, Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, 25, 334 (2007). 5. Y. Z. Wan, G. Y. Xiong, H. L. Luo, F. He, Y. Huang and Y. L. Wang, Applied Surface Science, 254, 5514 (2008). 6. R. Xu, G. Wu, X. Yang, T. Hu, Q. Lu and P. K. Chu, Materials Letters, 65, 2171 (2011).

Knowledge of the electrical behavior of refractory materials may enable the development and optimization of microwave nondestructive techniques to detect and evaluate changes in their physical properties while the materials are in service. This paper presents the results of a limited and preliminary investigation in which two refractory materials (dense chrome and dense zircon) were subjected to increasing temperature in a furnace and in which a frequency‐modulated continuous‐wave radar operating in the frequency range of 8–18 GHz radar was used to evaluate their attenuation properties.

A frequency‐modulated continuous‐wave (FM‐CW) handheld radar operating in the frequency range of 8–18 GHz, resulting in a relatively fine range resolution was designed and constructed for on‐site inspection of refractory structure thickness. This paper presents the design of the radar and the results of measurements conducted on typical refractory furnace structures assembled in the laboratory.

Die Moglichkeiten der Isokinetik mit der dokumentierbaren Erfassung von subjektiven und objektiven Befunden hat den Stellenwert der Isokinetik in den letzten Jahren wachsen lassen. Die fruhzeitige Einsetzung der Isokinetik hat das Spektrum der Krankengymnastik erweitert und die Kontrollierbarkeit des Therapieerfolges hat die Isokinetik zu einem unschatzbaren Baustein der Nachbehandlung insgesamt werden lassen. Zur Zeit fuhrt die Isokinetik die Nachbehandlung konkurrenzlos in ihrem Bereich an.

In den letzten zwanzig Jahren wurden etwa 50 morphologische Post-mortem-Untersuchungen an Schizophrenen-Gehirnen durchgefuhrt. Die Mehrheit dieser Studien untersuchte limbische Strukturen und fand dort diskrete, aber signifikante pathomorphologische Veranderungen in Form von Volumen- und Zellzahldefiziten sowie gestorter Zytoarchitektur, wohingegen drei Studien negative Ergebnisse erbrachten (Literaturubersicht s. Bogerts 1993). Limbische Strukturdefekte bei Schizophrenen konnten auch durch eine Reihe kernspintomographischer Untersuchungen nachgewiesen werden (Bogerts et al. 1991, Shenton et al. 1992). Weniger haufig wurde uber Zellausfalle und Strukturvolumendifferenzen im Kortex (Benes et al. 1986, Pakkenberg 1987), Thalamus (Treff und Hempel 1958, Lesch und Bogerts 1984, Pakkenberg 1990) und Basalganglien (Hopf 1954, Dom et al. 1981, Bogerts 1984) berichtet. Die meisten Autoren gehen davon aus, das die hirnstrukturellen Veranderungen sehr fruh, d. h. pranatal oder perinatal erworben wurden, nicht progressiv sind und deshalb als Vulnerabilitatsmarker zu betrachten sind (Weinberger 1987, Bogerts 1990, Murray et al. 1991, Stevens 1992). Die bisherigen Befunde zeigen, das die Neuropathologie der Schizophrenen subtil und keinesfalls so homogen und offensichtlich ist wie die der bekannten degenerativen Hirnerkrankungen. Fast alle bisherigen Untersuchungen wurden an relativ kleinen Fallzahlen durchgefuhrt und beschrankten sich auf wenige Hirnregionen.

In the analyses of cases of death in cold air environments, it is often of interest to determine the time required for the body of the individual to cool to ambient temperature. Usually such determinations have been based on Newton's law of cooling. This paper describes a case history in which this technique was experimentally tested and consequently abandoned in favour of a more complex biophysical model which more accurately described the thermo-physical events inherent in body cooling. This model is recommended for determination of the times required for various body parts to cool to ambient environmental temperatures.

In view of the environmental operating conditions, special techniques have to be used to permit the manufacture of the submerged type of motor as an industrial proposition. The first choice to be made is that of stator winding conductor insulation, which must be impervious to water, flexible to wind, and have good thermal stability. A thorough survey of the limited materials available for such an application determined that high density polythene, extruded on to a flexible stranded cable, would best meet these requirements. Polythene has a relatively low flow temperature, which may be increased, and the mechanical stability of the cable improved, if it is subjected to irradiation dosage. The cable and the necessary seal termination are subjected to accelerated life testing at operating conditions in static pressure vessels before commitment to production. The concept of the mechanical design calls for the use of small rotating diameters consistent with sound engineering practices. Where possible, rotating surfaces must be smoothed to minimize water turbulence losses.

In the analyses of cases of death in cold air environments, it is often of interest to determine the time required for the body of the individual to cool to ambient temperature. Usually such determinations have been based on Newton's law of cooling. This paper describes a case history in which this technique was experimentally tested and consequently abandoned in favour of a more complex biophysical model which more accurately described the thermo-physical events inherent in body cooling. This model is recommended for determination of the times required for various body parts to cool to ambient environmental temperatures.

General anesthesia causes a marked hypoxia in ruminants. We compared this phenomenon with anaesthesia related changes in the dog. Under alfentanil/etomidat anaesthesia some variables of the pulmonary circulation (TPR, PAP, PCWP) as well as arterial and venous blood gases and saturation (HbO2, pO2, ph) in dogs, sheep and calves were measured and calculated. The calculated pulmonary shunt fraction was compared between the three species. In ruminants there was an increase of total pulmonary resistance being associated with elevated PAP and decreased PCWP. The pulmonary shunt fraction was increased significantly and markedly during the surgical tolerance period, too. These parameters were not significantly changed in the dog. Ruminants seem to take an exceptional position concerning the anaesthesia related alterations of the pulmonary ventilation/perfusion system.