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The biological adaptation of the human lineage to its environment is a recurring question in paleoanthropology. Particularly, how eco-geographic factors (e.g., environmental temperature and humidity) have shaped upper airway morphology in hominins have been subject to continuing debate. Nasal shape is the result of many intertwined factors that include, but are not limited to, genetic drift, sexual selection, or adaptation to climate. A quantification of nasal airway (NA) morphological variation in modern human populations is crucial to better understand these multiple factors. In the present research, we study 195 in vivo CT scans of adult individuals collected in five different geographic areas (Chile, France, Cambodia, Russia, and South Africa). After segmentation of the nasal airway, we reconstruct 3D meshes that are analyzed with a landmark-free geometric morphometrics method based on surface deformation. Our results highlight subtle but statistically significant morphological differences between our five samples. The two morphologically closest groups are France and Russia, whose NAs are longer and narrower, with an important protrusion of the supero-anterior part. The Cambodian sample is the most morphologically distinct and clustered sample, with a mean NA that is wider and shorter. On the contrary, the Chilean sample form the most scattered cluster with the greatest intra-population variation. The South African sample is morphologically close to the Cambodian sample, but also partially overlaps the French and Russian variation. Interestingly, we record no correlation between NA volume and geographic groups, which raises the question of climate-related metabolic demands for oxygen consumption. The other factors of variation (sex and age) have no influence on the NA shape in our samples. However, NA volume varies significantly according both to sex and age: it is higher in males than in females and tends to increase with age. In contrast, we observe no effect of temperature or humidity on NA volume. Finally, we highlight the important influence of asymmetries related to nasal septum deviations in NA shape variation.

Real-world optimization scenarios under uncertainty and noise are typically handled with robust optimization techniques, which re-formulate the original optimization problem into a robust counterpart, e.g., by taking an average of the function values over different perturbations to a specific input. Solving the robust counterpart instead of the original problem can significantly increase the associated computational cost, which is often overlooked in the literature to the best of our knowledge. Such an extra cost brought by robust optimization might depend on the problem landscape, the dimensionality, the severity of the uncertainty, and the formulation of the robust counterpart.This paper targets an empirical approach that evaluates and compares the computational cost brought by different robustness formulations in Kriging-based optimization on a wide combination (300 test cases) of problems, uncertainty levels, and dimensions. We mainly focus on the CPU time taken to find robust solutions, and choose five commonly-applied robustness formulations: `"mini-max robustness'', "mini-max regret robustness'', "expectation-based robustness'', ``dispersion-based robustness'', and "composite robustness'' respectively. We assess the empirical performance of these robustness formulations in terms of a fixed budget and a fixed target analysis, from which we find that "mini-max robustness'' is the most practical formulation w.r.t.~the associated computational cost.

The COVID-19 pandemic forced changes to online teaching worldwide. The Clinical Anatomy journal club (JC) is key in the Bachelor of Science Honours (BScHons) programme and aims to improve scientific appraisal and communication abilities in anatomical research. An online JC through synchronous contact between members was deemed fitting as it could bridge the newly enforced geographical limitations due to the national lockdown in South Africa. Although common in clinical specialties, there are no published reports of anatomy themed online JCs. This project aimed to develop, implement, and appraise a synchronous virtual JC for Clinical Anatomy during the COVID-19 South African lockdown. A qualitative exploratory study design within an interpretive/constructivist paradigm was followed and aimed to explore students’ perceptions of a virtual anatomy JC during the lockdown. The study was conducted at a South African institution, within the BScHons programme, and all enrolled students were invited to participate. Upon receipt of informed consent, an anonymous questionnaire was administered via Moodle for the BScHons students. The responses were analysed by thematic analysis, codes were developed, and themes were generated. Two main themes were generated from the results: the first related to the virtual format of the JC and the second focused on the content and topics covered during the JC sessions. The Clinical Anatomy staff and students adapted rapidly to the virtual JC and formed a community of practice. The benefits of teaching and learning within JC were maintained during the virtual format. It is envisioned that the JC will continue in a hybrid format (face-to-face and virtual) in future academic years. Supplementary Information The online version contains supplementary material available at 10.1007/s40670-021-01325-8.

In a primer coating system used in aerospace applications to protect aluminum alloy substrate, praseodymium is added as corrosion inhibitors while CaSO4 is primarily added as filler materials. The interaction of Pr and CaSO4 is unknown. The goal of this study is to characterize any cooperative or synergistic inhibition between these two. Cooperative inhibition can be defined when one inhibitor enhances inhibiting effect of the other that already has inhibiting ability. Synergistic inhibition can be defined when one inhibitor activates the inhibiting effect of the other that originally does not inhibit. Optical profilometry, electrochemical techniques and X-ray photoelectron spectroscopy were used to characterize corrosion results. The results showed that several pit parameters will affirm the inhibition effect. Electrochemical results cannot always detect modest corrosion inhibitors. Cooperative inhibition was detected in pH 5 while synergistic inhibition was observed in pH 8. Synergistic inhibition occurs because SO4 2− helps with gelation of Pr to passivate the surface.

Nasal cavity is an anatomical region of the craniofacial skeleton that is the gate of the respiratory system. This cavity shows strong morphological variation, but the link between its shape and its function is not fully understood. Previous studies focusing on environmental factors (e.g. air temperature, humidity, altitude) demonstrated an influence of these factors on nasal morphology. However, it is difficult to disentangle this environmental influence from genetic, physiological and biome...

Improved spatial awareness is vital in anatomy education as well as in many areas of medical practice. Many healthcare professionals struggle with the extrapolation of 2D data to its locus within the 3D volume of the anatomy. In this chapter, we outline the use of touch as an important sensory modality in the observation of 3D forms, including anatomical parts, with the specific neuroscientific underpinnings in this regard being described. We explore how improved spatial awareness is directly linked to improved spatial skill. The reader is offered two practical exercises that lead to improved spatial awareness for application in exploring external 3D anatomy volume as well as internal 3D anatomy volume. These exercises are derived from the Haptico-visual observation and drawing (HVOD) method. The resulting cognitive improvement in spatial awareness that these exercises engender can be of benefit to students in their study of anatomy and for application by healthcare professionals in many aspects of their medical practice. The use of autostereoscopic visualisation technology (AS3D) to view the anatomy from DICOM data, in combination with the haptic exploration of a 3D print (3Dp) of the same stereoscopic on-screen image, is recommended as a practice for improved understanding of any anatomical part or feature. We describe a surgical innovation that relies on the haptic perception of patients' 3D printed (3Dp) anatomical features from patient DICOM data, for improved surgical planning and in-theatre surgical performance. Throughout the chapter, underlying neuroscientific correlates to haptic and visual observation, memory, working memory, and cognitive load are provided.

The effect of solution pH on layered double hydroxide (LDH) formation on electrogalvanized steel sheets (EG steel) was investigated in this study. EG steel with a Zn coating weight of 64 g/m2 was used as a substrate and was immersed in a 0.25 M Na2Al2O4-based solution having several pH values to form a Zn-Al-based LDH conversion coating. After rinsing and drying, corrosion resistance was evaluated by EIS. It was found that corrosion resistance increased with increasing pH up to pH 12.6. However, above this pH, corrosion resistance tended to display a sharp decrease. To understand this trend, the conversion coating was characterized by FT-IR, XRD and GDOES. The conversion coating was found to consist mainly of Zn2Al(OH)6(CO3)0.5·xH2O crystals (an LDH). The thickness of the conversion coating layer increased with increasing pH up to pH 12.4, but above this pH, its thickness tended to decrease due to the formation of ZnO. The reason for the dependence of corrosion resistance on solution pH is discussed from the viewpoints of the thickness and changes in the microstructure of the conversion coating layer, including its crystal size, density and uniformity, which could vary during the initial formation of ZnO at pH values above 12.6.

BACKGROUND: This study presents the outcomes of the management of chronic osteomyelitis of the appendicular skeleton according to an integrated approach at a dedicated bone infection unit in South Africa. METHODS: A retrospective record review identified 80 patients who were treated between January 2016 and December 2018. RESULTS: Sixty patients (75%) presented with fracture-related infections, 17 patients (21%) developed chronic osteomyelitis following haematogenous spread and three (4%) from contiguous wounds. According to the Cierny and Mader classification, 21 patients presented with anatomical type I, 14 with type II, 24 with type III and 21 with type IV chronic osteomyelitis. Positive microbial cultures were obtained in 63 (79%) cases. Follow-up for the cohort ranged from 1 to 29 months, with a mean follow-up of 10.4 months. The overall complication rate for the cohort was 6% and included sterile drainage from the surgical site after management with bioactive glass (S53P4), refracture after hardware removal, and development of non-union. Five patients experienced recurrence after the initial procedure to eradicate infection, resulting in an overall resolution rate of 94%. CONCLUSION: Using single-stage surgeries and tailored dead space management strategies according to a comprehensive integrated approach developed in South Africa, results comparable to international literature can be achieved. Level of evidence: Level 4. Keywords: chronic osteomyelitis, dead space management, bioactive glass, Lautenbach technique

Iliocapsularis (IC) is a small muscle overlying the capsule of the hip joint. Although recent attention is being given to this muscle by orthopedic surgeons who encounter it during the anterior approach to total hip arthroplasty, little is known about its anatomical features. The aim of this study was to review the anatomy of IC, and describe its’ origin, insertion, blood supply, innervation, muscle fiber characteristics and size. The function, clinical relevance and comparative anatomy of IC were also appraised. Using Evidence-Based Anatomy methodology, electronic databases were searched with the terms “iliocapsularis”, “iliacus minor”, “iliotrochantericus”, and “ilioinfratrochantericus” to identify eligible studies. Six studies (n = 287 lower limbs) examining the anatomy of IC were included. The pooled prevalence (PP) of the IC was 98.7% (95% CI 96.5–100.0). It arises from the inferior facet of the anterior inferior iliac spine (AIIS) and attaches inferior to the lesser trochanter. Attached to the anteromedial capsule along its entire length, IC has the largest capsular contribution of any of the hip muscles (73.8 ± 27.3 × 16.1 ± 4.4 mm). Thus, it is an important landmark in anterior surgical approaches to the hip joint. The anatomy of IC is becoming more relevant with the increasing use of anterior approaches to hip surgery. With attachments to the AIIS, the lesser trochanter as well as the length of the capsule, this muscle is an important landmark in total hip arthroplasty. Level V

Improved spatial awareness is vital in anatomy education as well as in many areas of medical practice. Many healthcare professionals struggle with the extrapolation of 2D data to its locus within the 3D volume of the anatomy. In this chapter, we outline the use of touch as an important sensory modality in the observation of 3D forms, including anatomical parts, with the specific neuroscientific underpinnings in this regard being described. We explore how improved spatial awareness is directly linked to improved spatial skill. The reader is offered two practical exercises that lead to improved spatial awareness for application in exploring external 3D anatomy volume as well as internal 3D anatomy volume. These exercises are derived from the Haptico-visual observation and drawing (HVOD) method. The resulting cognitive improvement in spatial awareness that these exercises engender can be of benefit to students in their study of anatomy and for application by healthcare professionals in many aspects of their medical practice. The use of autostereoscopic visualisation technology (AS3D) to view the anatomy from DICOM data, in combination with the haptic exploration of a 3D print (3Dp) of the same stereoscopic on-screen image, is recommended as a practice for improved understanding of any anatomical part or feature. We describe a surgical innovation that relies on the haptic perception of patients’ 3D printed (3Dp) anatomical features from patient DICOM data, for improved surgical planning and in-theatre surgical performance. Throughout the chapter, underlying neuroscientific correlates to haptic and visual observation, memory, working memory, and cognitive load are provided.

The anodic polarization response of magnesium alloy AZ31 was first characterized during exposure to aerated 0.1 M NaCl solutions with millimolar additions of NaVO3, Na3PO4, Na2HPO4, NaF and various pairings to assess their ability to inhibit corrosion kinetics and retard localized corrosion. Each of the candidate inhibitors reduced the corrosion rate of the alloy to some degree. A Na3PO4&ndash, NaVO3 pair produced a good inhibiting effect decreasing the corrosion rate to about 10&minus, 7 A/cm2, which was two orders of magnitude lower than the uninhibited control case. A Bliss Independence assessment indicated that this inhibitor pair acted synergistically. A Na2HPO4&ndash, NaVO3 pair reduced the corrosion rate to 10&minus, 6 A/cm2 but was not assessed to be acting synergistically. The NaVO3&ndash, NaF pair did not reduce the corrosion rate significantly compared to the control case and was an antagonistic pairing. SEM imaging showed film formation due to exposure, which appears to be the origin of the observed inhibition. The resistance to localized corrosion was assessed as the difference in the breakdown potential and the corrosion potential, with larger values indicating a lower probability of localized corrosion during free corrosion exposures. The effects of the inhibitors on this characteristic were mixed, but each of the inhibitor pairs yielded potential differences in excess of 100 mV. A conceptual conversion coating process based on a mixture of vanadate and phosphate compounds were demonstrated. A fluoride-bearing formulation produced coatings whose total impedance was increased by a factor of two compared to an uncoated control. A fluoride-free formulation produced coatings whose corrosion resistance was increased by more than a factor of three.

The anodic polarization response of magnesium alloy AZ31 was characterized during exposure to aerated 0.1M NaCl solutions with millimolar additions of NaVO3, Na3PO4, Na2HPO4, NaF and various pairings to assess their ability to inhibit corrosion kinetics and retard localized corrosion. Each of the candidate inhibitors reduced the corrosion rate of the alloy to some degree. A Na3PO4 - NaVO3 pair produced a powerful inhibiting response decreasing the corrosion rate to about 10-7 A/cm2, which was two orders of magnitude lower than the uninhibited control case. A Bliss Independence assessment indicated that this inhibitor pair acted synergistically. A Na2HPO4 - NaVO3 pair reduced the corrosion rate to 10-6 A/cm2 but was not assessed to be acting synergistically. The NaVO3 - NaF pair did not reduce the corrosion rate significantly compared to the control case and was an antagonistic pairing. SEM imaging showed film formation due to exposure, which appears to be the origins of the observed inhibition. The resistance to localized corrosion was assessed as the difference in the breakdown potential and the corrosion potential with larger values indicating a lower probability of localized corrosion during free corrosion exposures. Effects of the inhibitors on this characteristic were mixed, but each of the inhibitor pairs yielded potential differences in excess of 100mV. A conceptual conversion coating process based on a mixture of vanadate and phosphate compounds were demonstrated. A fluoride-bearing formulation produced coatings whose total impedance was increased by a factor or 2 compared to an uncoated control. A fluoride-free formulation produced coatings whose corrosion resistance was increased by more than a factor of 3.

We study the algebra of invariant representative functions over the N-fold Cartesian product of copies of a compact Lie group G modulo the action of conjugation by the diagonal subgroup. We construct a basis of invariant representative functions referred to as quasicharacters. The form of the quasicharacters depends on the choice of a reduction scheme. We determine the multiplication law of quasicharacters and express their structure constants in terms of recoupling coefficients. Via this link, the choice of the reduction scheme acquires an interpretation in terms of binary trees. We show explicitly that the structure constants decompose into products over primitive elements of 9j symbol type. For SU(2), everything boils down to the combinatorics of angular momentum theory. In the final part, we show that the above calculus enables us to calculate the matrix elements of bi-invariant operators occuring in quantum lattice gauge theory. In particular, both the quantum Hamiltonian and the orbit type relations may be dealt with in this way, thus, reducing both the construction of the costratification and the study of the spectral problem to numerical problems in linear algebra. We spell out the spectral problem for G=SU(2) and we present sample calculations of matrix elements of orbit type relations for the gauge groups SU(2) and SU(3). The methods developed may be useful in the study of virtually all quantum models with polynomial constraints related to some symmetry.

Aims: Variation of the sciatic nerve may increase the risk of iatrogenic injury during total hip arthroplasty or arthroscopy, result in failure of peripheral blocks, or be associated with piriformis syndrome. Studies from Africa are scarce, with none to date from South Africa. Thus, the aims were to document the relationship between the sciatic nerve and piriformis muscle, variation in the bifurcation level and in the length of the nerve. Any significant differences between sexes and sides were also investigated. Methods: The lower limbs of 42 cadavers (84 limbs) were dissected and the relationship between the sciatic nerve and piriformis classified according to the patterns described by Beaton and Anson. The region of sciatic nerve bifurcation was documented, and the length of the nerve was measured in individuals with bifurcation in the thigh. Results: The normal relationship between the sciatic nerve and piriformis muscle was present in 64 limbs (76.2%). The bifurcation level of the nerve was variable in more than half the sample. No significant differences occurred in any of the variant patterns or bifurcation regions between side or sex; however, variations were more common in females than in males. The mean length of the sciatic nerve was 133.30±19.33 mm, with no differences in length between sex or side. Conclusion: Variations in the anatomy of the sciatic nerve occurred in up to half of the sample, which may have implications for increased risk of iatrogenic injury in total hip arthroplasty and arthroscopy, piriformis syndrome or sciatic block failure. Level of evidence: Level 4

Our comprehensive cohort of 1100 unrelated achromatopsia (ACHM) patients comprises a considerable number of cases (~5%) harboring only a single pathogenic variant in the major ACHM gene CNGB3. We sequenced the entire CNGB3 locus in 33 of these patients to find a second variant which eventually explained the patients’ phenotype. Forty-seven intronic CNGB3 variants were identified in 28 subjects after a filtering step based on frequency and the exclusion of variants found in cis with pathogenic alleles. In a second step, in silico prediction tools were used to filter out those variants with little odds of being deleterious. This left three variants that were analyzed using heterologous splicing assays. Variant c.1663–1205G>A, found in 14 subjects, and variant c.1663-2137C>T, found in two subjects, were indeed shown to exert a splicing defect by causing pseudoexon insertion into the transcript. Subsequent screening of further unsolved CNGB3 subjects identified four additional cases harboring the c.1663–1205G>A variant which makes it the eighth most frequent CNGB3 variant in our cohort. Compound heterozygosity could be validated in ten cases. Our study demonstrates that whole gene sequencing can be a powerful approach to identify the second pathogenic allele in patients apparently harboring only one disease-causing variant. © 2019 Wiley Periodicals, Inc.

Commercial primers are applied on aluminum alloys that are used in aerospace applications to prevent corrosion attack from aggressive environments. These primers contain inhibitors that help combat corrosion. During field operations, these primers store and release inhibitors to protect the underlying alloy. The goal of this study is to characterize storage and release behaviors of these commercial primers to better understand the rate and mechanism by which inhibitors are released. Three commercial primers were investigated in this study; 1) Akzo Nobel 10P20-13 High Solid Primer that contains strontium chromate (SrCrO 4 ), 2) Deft 02GN084 (Pr-based), and 3) Hentzen 16708TEP (BaSO 4 -based). The primers were coated on a Teflon tape, then stripped off and broken to small pieces. Pieces of the primer coating were immersed into solutions of different Cl − concentration, temperature, time, and pH. The solutions were then filtered and characterized by inductively coupled plasma mass spectroscopy (ICP-MS) to analyze the solution chemistry. Results showed that SrCrO 4 primer release behavior follows power law kinetics. Solubility limits played an important role in dictating the release kinetics of the chromate primer when accumulation of Cr ion occurs.The effect of pH and temperature can alter this solubility limit. Chloride seems to promote release of chromate because of greater ionic strength. The Pr-rich primer released a large amount of Ca 2+ upon exposure and release kinetics were not time-dependent thereafter. The Ba-rich primer did not release soluble constituents to any significant extent.

This work demonstrates a novel organic conversion coating treatment on an AA2024-T3 substrate. The process is based on simple immersion in aqueous solutions containing an organic molecule, N-Benzoyl-N-phenylhydroxylamine (BPHA), after a hydrothermal oxide has been formed on the alloy surface. Potentiodynamic polarization results indicate that BPHA conversion coating outperforms coatings formed in the same concentration of other corrosion inhibitors, including NaVO 3 , Na 2 SiO 3 , CeCl 3 , and benzotriazole. BPHA coating also displays strong and persistent corrosion inhibition under ASTM B117 salt spray exposure conditions and static immersion testing. The cross-section of BPHA-coated substrate is prepared by focus ion beam-scanning (FIB), and analyzed by high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) coupled with energy dispersive spectroscopy (EDS), which show a thick surface film with a three-layer structure. Raman spectroscopy and XPS are used to examine the surface chemistry of BPHA-coated samples, both of which suggest the formation of a BPHA surface film, possibly stabilized by the keto-to-iminol conversion that made the BPHA molecule strongly nucleophilic. The formation of BPHA-metal oxide complex seems to be closely related to the excellent corrosion resistance of BPHA coating.

The fabrication and application of zinc ferrocyanide ion exchange compounds for use as inhibiting and sensing pigments in protective paints and primers for metals and alloys are described in this paper. A distinctive property of these ferrocyanide pigments is an ability to store corrosion inhibitors and then release them when needed by an ion exchange process. The exchange process is triggered when moisture containing Na+ and K+ ions contacts inhibitor particles embedded in an organic coating. The exchange kinetics were studied by measuring the concentration of released zinc ions in the solution with inductively coupled plasma. The inhibitor storage capacity can be as high as 200 meq/100 g, and it is much higher than that found in other reported ion exchange compounds. Furthermore, structure changes from non-crystalline to crystalline, upon exchange with alkaline ions, can be detected by x-ray diffraction, providing an important indication of activation of the corrosion protection. This is a form of corrosion sensing. The inhibition performance of zinc ferrocyanide in the coating was examined by salt spray tests and electrochemical impedance spectroscopy, and both tests showed that zinc ferrocyanide could provide good protection on aluminum alloy 2024.

Chronic osteomyelitis is a challenging condition to treat and although no exact treatment guidelines exist, the surgical management strategy includes wide resection of necrotic and infected bone followed by dead space management. This study evaluates the use of bioactive glass as a single-stage procedure for dead space management following surgical debridement. A consecutive series of 24 patients with Cierny-Mader type 3 osteomyelitis, treated between March 2016 and June 2018, were identified and evaluated retrospectively. Patients were managed with bioactive glass as dead space management following surgical debridement. Of the patients who completed more than 12 months follow-up, all fourteen (100%) showed complete resolution of symptoms. Of the remaining ten patients with less than 12 months follow-up, eight had complete resolution of symptoms. Therefore, a preliminary result of 22 out of 24 patients (91.65%) had resolution of symptoms following debridement and dead space management with bioactive glass. One patient experienced a complication related to the use of bioactive glass. This manifested as prolonged serous wound drainage that resolved with local wound care. The use of bioactive glass appears to be effective for dead space management following debridement of anatomical type 3 chronic osteomyelitis of the appendicular skeleton.

The purpose of this study was to accurately establish the anatomical variability of the third metacarpal, its medullary canal, and the relationship with the capitate in the context of high rates of component loosening still seen in total wrist arthroplasty. CT scans of a 100 hands (age: 41 ± 14 years (range: 16–71 years); male/female ratio: 53/47) were studied to establish the detailed anatomy of the third metacarpal and the capitate. Although the shape of the third metacarpal and the angles formed with the capitate were highly variable, the third metacarpal length was longer in males (p

This analysis examines long-term projections of U.S. federal budget totals. The predictions are largely driven by a growing elderly population. Spending on Social Security, Medicare, and Medicaid grows more rapidly than tax revenues and ultimately causes an explosion in the debt-to-GDP ratio. Two surprises have moderated this growth. One is unusually low interest rates and the other was the surge in revenues related to the dot-com boom of the late 1990s. One surprise—the Great Recession—caused the debt-to-GDP ratio to rise briefly much faster than expected. Despite these surprises the rapid growth of programs serving the elderly has been forecasted fairly accurately. The analysis ends by discussing program designs that adjust to surprises by changing indexing or using trigger mechanisms.

International audience; Organic pig husbandry systems in Europe are diverse – ranging from indoor systems with concrete outside run (IN) to outdoor systems all year round (OUT) and combinations of both on one farm (POUT). As this diversity has rarely been taken into account in research projects on organic pig production, the aim of this study was to assess and compare pig health, welfare and productivity in these three systems. Animal health and welfare were assessed using direct observation and records of 22 animal-based measures, comprising 17 health-, 3 productivity- and 2 behavioural measures. These were collected in pregnant sows, weaners and fattening pigs during direct observations and from records within a cross-sectional study on 74 farms (IN: n=34, POUT: n=28, OUT: n=12) in eight countries. Overall, prevalence of several animal health and welfare issues was low (e.g. median 0% for pigs needing hospitalisation, shoulder lesions, ectoparasites

The study of protective film formation on Mg alloys by exposure to sodium selenite solutions was conducted. Anodic polarization studies, electrochemical impedance spectroscopy studies, morphological analysis, and Energy-dispersive X-ray spectroscopy were performed on AZ31 Mg alloy after coating treatment in different concentrations of sodium selenite. The corrosion resistance was improved by around 5 times compared with control. Improved resistance to localized corrosion was observed in the coatings treated by 5 mM or 10 mM sodium selenite. The protection mechanism was ascribed to the transformation of selenite to insoluble selenium, the formation of insoluble MgSeO3 hydrate, and polymerization of amorphous selenium.

Redistribution of impurities during the dissolution of AZ91 and synthesized Mg-0.5Cu alloys were studied with rotating ring-disk collection experiments and stripping voltammetry. In solution, where the potential value of both alloys is far below the equilibrium potential values of Cu oxidation reactions, nonfaradic release of Cu particles led to the production of Cu ions which were subsequently reductively collected on an outer Pt ring. The collected Cu was analyzed and confirmed with stripping voltammetry. The results of this work support the notion that isolated Cu atoms or Cu-rich particles can be oxided in aerated solutions at low potential values, and generated Cu ions can be reductively redeposited on a Mg alloy surface.

Combination studies of neurokinin 1 (NK1) receptor antagonists and serotonin-selective reuptake inhibitors (SSRIs) have shown promise in preclinical models of depression. Such a combination may offer important advantages over the current standard of care. Herein we describe the discovery and optimization of an indazole-based chemotype to provide a series of potent dual NK1 receptor antagonists/serotonin transporter (SERT) inhibitors to overcome issues of ion channel blockade. This effort culminated in the identification of compound 9, an analogue that demonstrated favorable oral bioavailability, excellent brain uptake, and robust in vivo efficacy in a validated depression model. Over the course of this work, a novel heterocycle-directed asymmetric hydrogenation was developed to facilitate installation of the key stereogenic center.

In this study, the electrochemical properties of synthesized intermetallic compounds (IMCs) similar to those commonly found in AA2024-T3 were studied in neutral 0.1 M NaCl at 10, 30, 50, and 70°C using the electrochemical microcell method. Results on the synthesized IMCs were combined with and supported by analysis of free corrosion experiments performed on AA2024-T3. Results reveal that, in general, corrosion rates of the IMCs increase with temperature and pitting potentials of most IMCs show a slight decrease with temperature. Increased dealloying kinetics of S-phase with increasing temperature was evident in both open-circuit potential transients and post-exposure corrosion morphology characteristics, leading to increased Cu surface areas and a higher likelihood of the propagation of localized corrosion into the matrix. The corrosion potential of synthesized Al-Cu-Mn-Fe type particles was found to be cathodic to the matrix at low temperatures, but anodic to the matrix at high temperatures. This high-te...

This manuscript presents the formulation and implementation of a phase field model for simulating the activation- and diffusion-controlled pitting corrosion phenomena in metallic materials. Introducing an auxiliary phase field variable to represent the physical state of each material point, the free energy of the corroding metal–electrolyte system can be expressed as a function of field variables and their gradients. The governing equations for the evolution of each field variable are then derived such that the system free energy is decreased during the mass transfer and metal dissolution processes. The propagation of the diffuse interface is tracked implicitly by solving the phase field variable over the entire system, which allows the accurate approximation of complex morphological evolutions. A comprehensive study is presented to verify the accuracy of the proposed model. We show that by calibrating the interface kinetics parameter with the exchange current density, the proposed model can reproduce different portions of the polarization curve associated with the activation-controlled, diffusion-controlled, and mixed-controlled corrosion kinetics. We also demonstrate the application of this model for simulating the electropolishing process, interactions between multiple growing pits, and pitting corrosion in a metal matrix composite and a polycrystalline stainless steel.

With regards to localized corrosion, the role of uniform corrosion of aluminum alloys has not always been accounted for in the past. The impact of uniform corrosion on aluminum alloys 2024-T3, 6061-T6, and 7075-T6 is studied here to provide quantitative evidence of its importance. Preliminary weight loss experiments combined with optical profilometry (OP) indicate that corrosion attributed to uniform corrosion is very significant when compared to localized corrosion. A series of free immersion tests were conducted to understand the influence of environmental variables including temperature (20, 40, 60, 80 °C), initial pH without buffering (3, 5, 8, 10) and chloride concentration (0.01, 0.1, 1 M) for 1, 7, and 30 days. With time, uniform corrosion results exhibited a strong dependence on temperature accompanied by variable pH- and temperature-dependent corrosion product formation. Electrochemical approaches including electrochemical impedance spectroscopy (EIS) and cathodic polarization were utilized to characterize the oxygen reduction reaction (ORR) and corrosion product formation as a function of temperature. Electron microscopy was conducted to assess the microstructure and morphology of corrosion products and provide supporting evidence for electrochemical findings.

This manuscript presents the formulation and application of the Green’s Discrete Transformation Method (GDTM) for the meshfree simulation of transient diffusion problems, including those with moving boundaries. The GDTM implements a linear combination of time-dependent Green’s basis functions defined on a set of source points to approximate the field in the form of a solution series. A discrete transformation is implemented to evaluate unknown coefficients of this series, which eliminates the need to use time integration schemes. We will study the optimal number and location of the GDTM source points that yield the highest level of accuracy, while maintaining a manageable condition number for the resulting linear system of equations. The optimal values of these parameters, which are inherently independent of the domain geometry, are determined such that the basis functions have appropriate features for approximating the field. A comprehensive convergence study is presented to show the precision and convergence rate of the GDTM for modeling various diffusion problems. We also demonstrate the application of this method for simulating three diffusion problems with complex and evolving morphologies: heat transfer in a turbine blade, thermal response of a porous material, and localized (pitting) corrosion in stainless steel. Copyright c 2015 John Wiley & Sons, Ltd.

The current tribological research is intended to achieve maximum wear resistance under the structural adaptability of tribocoupling elements, which requires application of means to reduce the activation of the metal surface layers, decrease in frictional work, regulation of passivation and temperature control. The aim of this study is to identify the patterns that influence the kinetics formation of the boundary layers of lubricating mineral gear oil on activated friction contact surfaces, and the increment of the friction specific work on wear-resistant steel 42Cr4 and 100Cr6 in frequent start and stop operation mode. Due to the activation of surface layers of metal in the non-stationary operating conditions of the contact surfaces, the gradual forming of the boundary lubricant adsorption layers with increased effective viscosity in contact occurs, exhibiting high adaptation ability, and the boundary layer thickness is from 0.2 to 4 microns. This research analyzed the lubricating ability of oil at the starting maximum torque of friction, showing that the thickness of the oil layer formed in contact had a dual nature—boundary and hydrodynamic. The pure rolling conditions promote localization of shear in the lubricating layers, and the high frictional properties of the transmission oil have been identified regardless of the hardness of the investigated surfaces.

Impedance spectra for the secondary phase particles that populate in aluminium alloy 2024-T3 are presented. Such impedance data using an electrochemical microcell have not been previously reported, and were possible via a fast Fourier transform-based technique. The interfacial characteristics of intermetallic particles in NaCl and chromate solutions were described by a simplified Randles circuit. Impedance analysis, along with anodic polarization, demonstrated that Al 2 CuMg (S-phase) showed the highest dissolution propensity, while the other phases studied were net cathodes. Based on the capacitance measurements determined, the dealloying of S-phase was evaluated in-situ.

[Image: see text] In solving the P-gp and BCRP transporter-mediated efflux issue in a series of benzofuran-derived pan-genotypic palm site inhibitors of the hepatitis C virus NS5B replicase, it was found that close attention to physicochemical properties was essential. In these compounds, where both molecular weight (MW >579) and TPSA (>110 Å(2)) were high, attenuation of polar surface area together with weakening of hydrogen bond acceptor strength of the molecule provided a higher intrinsic membrane permeability and more desirable Caco-2 parameters, as demonstrated by trifluoroacetamide 11 and the benchmark N-ethylamino analog 12. In addition, the tendency of these inhibitors to form intramolecular hydrogen bonds potentially contributes favorably to the improved membrane permeability and absorption. The functional group minimization that resolved the efflux problem simultaneously maintained potent inhibitory activity toward a gt-2 HCV replicon due to a switching of the role of substituents in interacting with the Gln414 binding pocket, as observed in gt-2a NS5B/inhibitor complex cocrystal structures, thus increasing the efficiency of the optimization. Noteworthy, a novel intermolecular S=O···C=O n → π* type interaction between the ligand sulfonamide oxygen atom and the carbonyl moiety of the side chain of Gln414 was observed. The insights from these structure–property studies and crystallography information provided a direction for optimization in a campaign to identify second generation pan-genotypic NS5B inhibitors.

will manually insertUS fiscal policy has long been unsustainable, driven largely by automatically growing entitlement spending and insufficient revenues. Often overlooked is the extent to which this preordained fiscal policy limits policymakers’ discretion to act on new priorities each year, whether through newly legislated increases in spending or through tax reductions. This study lays out reforms to the federal budget process that could restore greater discretion to congressional lawmakers, so that a greater share of revenues is not automatically allocated without any vote by a current Congress. Such reforms include various triggers in entitlement and tax programs that limit their automatic growth, more transparent reporting and informative displays of budget information, and more requirements to subject programs to periodic review and reauthorization. Examples are provided for how such reforms could be applied to specific entitlement and tax programs.

Most metallic alloys are susceptible to corrosion in their service environments. One of the most practical and cost-effective ways to slow or stop corrosion is by application of a protective coating or paint. Coatings and paints can be applied to large surface areas and are protective, even though they are relatively thin. They can be applied rapidly and the associated material and labor cost is usually much less than the cost (or value) of the object being protected. Over the past 150 years, corrosion resistant coating and paint technology has evolved steadily, resulting in a vast array of products for protecting many different substrates under many different conditions. Coating technology is certainly a mature discipline, but the field continues to evolve as new substrates are developed and made available for application and as new coatings and application methods are devised to meet emerging demands and constraints. Over the past 30 years, the desire to lower the toxic hazard and pollution has strongly influenced coating technology. This has resulted in the emergence of new coating systems and methods of application. This chapter focuses on issues related to protective coatings and paints used for structural metals and alloys used in high volume applications.

Temperature and pH influence on uniform corrosion of 2024-T3 aluminum alloys is reported through a series of free immersion tests. Extensive results performed in various pH (3 to 10), Cl-, and temperatures (20⁰C to 80⁰C) from 1 day up to 1 month are reported to mimic real applications. A comparison with weight loss experiment is demonstrated to provide a quantitative significance of pitting versus uniform corrosion. Severity of uniform corrosion is measured at various pH, temperature, and time. Electrochemical approaches including electrochemical impedance spectroscopy (EIS) and cathodic polarization are utilized characterizing oxygen reduction reaction (ORR) and passivation at different temperatures. Passive film and corrosion product analysis is conducted by electron microscopies to assess microstructure, morphology, and corrosion product formation driven by temperature.

Depression is a serious illness that affects millions of patients. Current treatments are associated with a number of undesirable side effects. Neurokinin 1 receptor (NK1R) antagonists have recently been shown to potentiate the antidepressant effects of serotonin-selective reuptake inhibitors (SSRIs) in a number of animal models. Herein we describe the optimization of a biaryl chemotype to provide a series of potent dual NK1R antagonists/serotonin transporter (SERT) inhibitors. Through the choice of appropriate substituents, the SERT/NK1R ratio could be tuned to afford a range of target selectivity profiles. This effort culminated in the identification of an analog that demonstrated oral bioavailability, favorable brain uptake, and efficacy in the gerbil foot tap model. Ex vivo occupancy studies with compound 58 demonstrated the ability to maintain NK1 receptor saturation (>88% occupancy) while titrating the desired level of SERT occupancy (11-84%) via dose selection.

Although recent performance and the short-term outlook for the U.S. federal budget deficit have been favorable, the good news is not expected to continue. Low interest rates and slowly growing health costs have helped ease the burden of debt, but they are not expected to continue for very long. A likely combination of growing spending on Social Security, Medicare, and Medicaid and higher interest rates would increase the drag on the American economy. This paper analyzes which expenditures do and do not cause a significant increase in the federal debt and describes how a remedy implies difficult choices that require leaders of both political parties “to join hands and jump off the cliff together.”

A new meshfree method based on a discrete transformation of Green's basis functions is introduced to simulate Poisson problems with complex morphologies. The proposed Green's Discrete Transformation Method (GDTM) uses source points that are located along a virtual boundary outside the problem domain to construct the basis functions needed to approximate the field. The optimal number of Green's functions source points and their relative distances with respect to the problem boundaries are evaluated to obtain the best approximation of the partition of unity condition. A discrete transformation technique together with the boundary point collocation method is employed to evaluate the unknown coefficients of the solution series via satisfying the problem boundary conditions. A comprehensive convergence study is presented to investigate the accuracy and convergence rate of the GDTM. We will also demonstrate the application of this meshfree method for simulating the conductive heat transfer in a heterogeneous materials system and the dissolved aluminum ions concentration in the electrolyte solution formed near a passive corrosion pit.

This research is sponsored by the U.S. Air Force Academy under agreement number FA7000-12-2-0015. The U.S. Government is authorized to reproduce and distribute reprints for Governmental purposes notwithstanding any copyright notation thereon. The views and conclusion contained herein are those of the authors and should not be interpreted as necessarily represented official policies or endorsement, either expressed or implied, of the U.S. Air Force Academy or the U.S. Government.

Research was sponsored by the Army Research Laboratory and was accomplished under Cooperative Agreement Number W911NF- 14-2-0004. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the Army Research Laboratory or the U.S. Government. The U.S. Government is authorized to reproduce and distribute reprints for Government purposes notwithstanding any copyright notation herein. Purchase of the Raman microprobe was supported by the National Science Foundation under Grant No. 0639163.